Method and device for breastfeeding control

FIELD: medicine.

SUBSTANCE: group of inventions refers to medicine, namely to paediatrics, and can be used to control an amount of breast milk consumed by a nursing infant. The method involves measuring a breast electric resistance and a breast electric capacity before and after breastfeeding. The derived values are multiplied to obtain the characteristics variation information during the breastfeeding. The change information are related to the amount of milk consumed by the infant. What is presented is a breastfeeding control system, which comprises an electric capacity measuring unit designed for measuring the electric capacity variations before and after breastfeeding. Besides, the system comprises a breast electric resistance measuring unit. Also, the system comprises a processing unit configured to calculate the product of the electric capacity and the electric resistance, and to match the derived product with the amount of milk consumed by the nursing infant.

EFFECT: inventions enables controlling the amount of breast milk consumed by the infant and assessing the adequacy of breastfeeding.

16 cl, 20 dwg, 3 ex

 

RELATED APPLICATIONS

This application claims the priority of patent application U.S. No. 61/006558, filed January 22, 2008, and patent application U.S. No. 61/053069, filed may 14, 2008. The contents of the above documents have been incorporated by reference as if they were fully described herein.

The SCOPE AND LEVEL of TECHNOLOGY

The present invention in some embodiments, implementation refers to breastfeeding and more specifically, but not exclusively, to a method and device for monitoring breastfeeding by measuring electrical capacitance. It is generally accepted that breastfeeding is beneficial for both infants and mothers. Pediatricians and other health professionals have to say about breastfeeding as a normal part of everyday life and encourage mothers to breastfeed until it is mutually desirable. Breastfeeding is beneficial for babies from the point of view of General health, growth, development. In particular, breastfeeding significantly reduces the risk of a large number of acute and chronic diseases. For example, studies show that breastfed babies are less prone diarrhea, ear infections, respiratory infections, bacteraemia, bacterial meningitis, botulism, necrotic enterocolitis and infection is capoluogo tract. In addition, breastfeeding gives your baby the feeling of closeness, warmth and security. Many studies show that breast-feeding is also beneficial for the mother. For example, statistically, mothers, breastfeeding, and more quickly return to their normal weight. Breastfeeding is also known as one of the factors that delay the recovery of ovulation that can be beneficial for mothers or families who want to increase the interval between births. In some cases, the quantity of breast milk consumed by children breastfed, is not enough. If the child is breastfed stress occurs, it is desirable to control the amount of milk consumed by the child, to determine whether or not the lack of power is one of the sources of stress. There are several ways of monitoring breastfeeding.

The most widely used method is to subtract the weight. According to this method, the child's weight is measured before and after breastfeeding, and the amount of milk consumed is calculated by finding the difference between the two weight values.

Another method disclosed in the article by Daly and others (Daly et al.), Exp.Discrimination, 77, 79-87 (1992). According to this method, changes in the volume of the chest track, taking pictures of the breast before and after food is placed.

In published application U.S. No. 20058271913 and published international patent application no WO 2006/054287 disclosed method, whereby the volumetric flow sensor is placed in a silicone nipple, which is given to the child. Data on the consumption of milk from the sensor is converted into data on the volume of milk that is displayed on the monitor.

In international patent application no WO 2006/054287 disclosed control of breastfeeding by Doppler measurements. Doppler ultrasonic transmitting and receiving probes, located close to the nipple, are activated when breastfeeding for measuring the volume flow through the nipple. This volume flow is converted, collects and provides data on the volume of milk.

BRIEF description of the INVENTION

According to one aspect of some embodiments of the present invention, a method of monitoring the amount of milk consumed by the baby that is breastfed. This method includes: detecting changes in electrical capacitance of the breast during breastfeeding and the correlation of changes in electrical capacitance with the amount of milk consumed by the baby.

According to some variants of the invention, the method also includes measuring the electrical capacitance to determine such changes.

According to some versions is sushestvennee of the invention the measurement of electric capacity to perform, in order to evaluate the electric capacity of the inside of the chest with the subtraction of the contribution of breast skin in electric capacity.

According to some variants of the invention, the measurement of electrical capacitance includes a measurement of the phase voltage selected from the chest in response to electric current applied to the skin.

According to some variants of the invention, the phase measured by at least four electrodes attached to the skin of the breast.

According to some variants of the invention, the method also includes adjusting the ratio using the historical data collected during previous sessions of breastfeeding. According to some variants of the invention, the method also includes measuring the electrical resistance of the chest and the calculation result of the multiplication of electric resistance, electric capacity, and the quantity of milk is correlated with the result of the multiplication.

According to some variants of the invention, the method also includes performing a calibration measurement before breastfeeding to collect calibration data, and the result of the multiplication is adjusted on the basis of the calibration data.

According to some variants of the invention, the pic is b, in addition, includes the use of the multiplication to search on the chest areas occupied by clusters of alveoli.

According to some variants of the invention, the method also includes the subtraction of the contribution of breast skin in electric capacity. According to some variants of the invention, the contribution of the skin in the electrical capacity and the total capacity of the chest measure different electrical circuits.

According to some variants of the invention, the method also includes measuring the thickness of the skin, and the contribution of the skin in electric capacity estimate based on the thickness.

According to some variants of the invention, the capacitance measuring device for measuring the electrical capacitance without electrical contact with the skin.

According to some variants of the invention, the electric capacitance is measured, at least partially, at least one device selected from the group consisting of a capacitive bridge, inductive-resistive-capacitive probe and device for measuring the oscillation frequency.

According to some variants of the invention, the electrical capacity is measured by a certain number of electrodes, and the method is used for at least one cycle multiplexing, which can be played at different paced sub-cycles cycle multiplexing to use another set of electrodes to measure the electrical capacity.

According to some variants of the invention, the method also includes using the values of electrical capacitance is measured during at least one cycle multiplexing, to determine the measurement of electrical capacitance on the chest in future sessions.

According to some variants of the invention, the method also includes the analysis of values of electrical capacitance is measured during at least one cycle multiplexing to distinguish between the sensitivity of measurements at different depths in the chest.

According to one aspect of some embodiments of the present invention proposed monitoring breastfeeding. The system includes a unit of measurement of electric capacity, adapted for measuring changes in electrical capacitance of the breast during breastfeeding, and the processing unit for correlating the changes in electrical capacitance with the amount of milk consumed by the baby through breastfeeding.

According to some variants of the invention, the unit of measurement of electrical capacitance is configured to measure electrical capacitance inside the chest with the subtraction of the contribution of breast skin in electric capacity.

According to some variants of the invention, the measurement unit when the first vessel is configured to determine the electrical capacity on the basis of the phase voltage, selected from the chest in response to electric current applied to the skin.

According to some variants of the invention, the unit of measurement of electrical capacitance includes at least four electrodes connected to the skin of the breast.

According to some variants of the invention, the system also contains the environment memory for storing historical data collected in previous sessions of breastfeeding, and a processing unit configured to correct the correlation using historical data.

According to some variants of the invention, the system further contains a unit of measurement of resistance to measure the electrical resistance of the chest, and a processing unit configured to compute the result of multiplying the electric resistance electric capacitance, and the amount of milk correlated with the result of the multiplication.

According to some variants of the invention, the processing unit configured to correct the result of the multiplication on the basis of the calibration data collected before breastfeeding.

According to some variants of the invention, the electric resistance and electric capacitance is measured at several frequencies, and the multiplication is performed for each cha is toty, and with the amount of milk correlated with a combination of at least two results of the multiplications.

According to some variants of the invention, the processing unit configured to subtract the contribution of breast skin in electric capacity.

According to some variants of the invention, the unit of measurement of electrical capacitance includes a circuit for measuring the electrical capacitance of the skin, configured to measure the contribution of the skin, and the scheme of measurement of the total electrical capacitance of the skin, configured to measure the total electrical capacity of the breast.

According to some variants of the invention, the system also contains a device for measuring the thickness of the skin, and the processing unit is configured to assess the contribution of the skin in electric capacity based on thickness.

According to some variants of the invention, the unit of measurement of electrical capacitance is configured to measure electrical capacitance, being electrically isolated from the skin of the breast.

According to some variants of the invention, the unit of measurement of electrical capacitance includes at least one device selected from the group consisting of a capacitive bridge, inductive-resistive-capacitive probe and device for measuring the oscillation frequency.

According to some the variants of the invention, the electric capacitance is measured at frequency less than 100 MHz.

According to some variants of the invention, the electrical capacity is measured by a certain number of electrodes, and the system includes a controller for applying at least one cycle multiplexing to various paced sub-cycles cycle multiplexing for measuring electrical capacitance used a different set of electrodes.

According to some versions of the invention the processing unit is configured to use values of electrical capacitance is measured during at least one cycle multiplexing, in order to determine locations for measuring capacitance on the chest in future sessions.

According to some variants of the invention, the processing unit configured for analyzing the values of electrical capacitance is measured during at least one cycle multiplexing to distinguish between the sensitivity of measurements at different depths in the chest.

If not given another definition, all technical and scientific terms used herein have the same meaning, which usually knows the average expert in the field to which the invention relates. Although methods and materials similar or equivalent to those described herein can be used in the practical implementation and testing of embodiments of the invention, the following describes illustrative methods and/or materials. In case of conflict the advantage is the description of the invention, including definitions. In addition, the materials, methods and examples are illustrative only and are not intended to be limiting.

Implementation of the method and/or system embodiments of the invention may involve performing or completing selected tasks manually, automatically or in combination. Moreover, according to actual instrumentation and equipment of embodiments of the method and/or system of the invention, some of the selected task can be implemented in hardware, software, firmware or combination thereof using the operating system.

For example, the hardware to perform selected tasks according to variants of the invention can be implemented as a chip or circuit. For software selected tasks according to variants of the invention can be implemented as a set of programming instructions executable by a computer using any suitable operating system. In one illustrative embodiment of the invention one or more tasks according to illustrative options for the implementation of the act is both and/or systems described herein, performs a processor, such as a computing platform for executing a set of commands. Optionally, the processor includes a volatile memory for storing commands and/or data and/or nonvolatile memory such as a magnetic hard disk and/or removable media, for storing commands and/or data. The choice is also provided a network connection. Also, optionally, a monitor and/or user input device, such as a keyboard or a mouse.

BRIEF DESCRIPTION of DRAWINGS

Some embodiments of the invention described herein is for example only and with reference to the accompanying drawings. Now with particular reference to the detailed drawings necessary to emphasize that details are shown for example only and for purposes of illustrative descriptions of embodiments of the invention. In this regard, the description taken with the drawings making apparent to experts in this field, as can be carried out in practice, embodiments of the invention. In the drawings:

FIG.1 is a structural diagram illustrating a method suitable for controlling the quantity of milk consumed by the baby is breastfed, according to various illustrative options for the implementation of the present invention;

The IG.2 - structural diagram of a method in the variants of implementation, in which the quantity of milk is correlated with the electric capacity and electric resistance of the breast;

FIG.3 a-b is a schematic illustration of the configuration of the electrodes on the chest, according to various illustrative options for the implementation of the present invention;

FIG.4 is a schematic illustration of the electrical analogue of the configuration of FIG.3;

FIG.5 is a schematic illustration of a three-component electrical analog of the internal breast tissue according to various illustrative options for the implementation of the present invention;

FIG.6 is a schematic illustration of a variant of implementation of the present invention, in which for measuring the electrical capacitance use the pad;

FIG.7 is a schematic illustration of a control system of breastfeeding according to various illustrative options for the implementation of the present invention;

FIG.8 is a schematic illustration showing the socket, which collapses during milk ejection;

FIG.9 is a schematic illustration showing the location of the alveoli according to the computational model used in some embodiments to implement the present invention;

FIG.10 shows the electrical capacity in nanofarad as a function of the volume of milk consumed in milliliters by measuring enum in experiments, made according to some variants of implementation of the present invention;

FIG.11 shows the result of multiplying the electric resistance electric capacitance as a function of the volume of milk consumed by the measurement frequency of 50 kHz in the experiments performed according to some variants of implementation of the present invention;

FIG.12 shows the result of multiplying the electric resistance electric capacitance as a function of the volume of milk consumed by measurements for a frequency of 25 kHz in the experiments performed according to some variants of implementation of the present invention;

FIG.13 shows the ratio of the electrical resistance of intracellular water with an electric resistance of the alveoli as a function of the volume of milk consumed by the measurements in experiments performed according to some variants of implementation of the present invention;

FIG.14 shows the capacitance as a function of time for a frequency of 50 kHz for measurements in another series of experiments performed according to some variants of implementation of the present invention;

FIG.15 shows the measured electrical capacity with FIG. 14 as a function of the consumption of milk;

FIG.16 shows the electrical resistance as a function of time for a frequency of 50 kHz measured by the holes in the experiments, made according to some variants of implementation of the present invention;

FIG.17 is a histogram of experimental results obtained after applying operations adjustments according to various illustrative options for the implementation of the present invention;

FIG.18 shows the raw signal electrical capacitance as a function of time for measurements in experiments performed according to some variants of implementation of the present invention.

FIG.19 shows the raw signal electrical capacitance as a function of time according to measurements in another series of experiments performed according to some variants of implementation of the present invention.

DESCRIPTION of SPECIFIC embodiments of the INVENTION

The present invention, in some embodiments, implementation refers to breastfeeding, and more specifically, but not exclusively, to a method and device for monitoring breastfeeding by measuring electrical capacitance.

Before a detailed explanation of at least one variant of the invention, it should be noted that the invention is not necessarily limited in its application to details of construction and arrangement of components and/or methods set forth in the following description and/or illustrated in the drawings and/and the and in the Examples. The invention can be implemented in other ways or in different ways.

The authors of the present invention have found that the amount of milk in the breast can be correlated with the electrical capacity of the chest. It is recognized that the amount of milk before and after breast feeding can be used to estimate the amount of milk consumed by the baby breastfeeding. This is because the typical speed of feeding the child is approximately 400 ml per hour, while the rate of milk production in the breast is usually less than 60 ml per hour (on average, approximately 30 ml per hour). Thus, the amount of milk, differentiated by time, with the addition of the average speed of production leads to an estimated rate of consumption within the limits of error of 7% with a maximum of confidence.

Therefore, the authors of the present invention has developed a method of controlling the intake of milk by measuring the electrical capacitance of the breast. Now will be explained the dependence of the quantity of milk (volumetric or mass) on the electrical capacity of the breast according to the opening of the authors of the present invention.

The milk is stored in the alveoli of the breast, which are small glands with a diameter of approximately 0.1 mm At the time of milk ejection in the size of the alveoli decreases. The membrane of each alveoli leads SEB is as a dielectric layer, because it blocks the ionic conductivity. In AC electric fields these membranes spend bias currents, therefore, affect the electrical capacity of the chest. More specifically, the average cross-section of alveoli in an arbitrary orientation can be monitored by measuring the electrical capacitance of the breast. It is recognized that the average cross-section of alveoli is their average volume, and therefore also the volume of milk in the breast.

Without being bound to any theory, it is predicted that the shape and size of alveoli is approximately universal, because the milk is retained in the alveoli only due to molecular forces. The size of the alveoli, on the one hand, to prevent spontaneous drainage of milk and, on the other hand, allow to consume milk at relatively low power of the suction. Based on this approximation, the ratio between the measured electrical capacity and the volume of milk is also universal.

In the chest there are two types of tissue that is compressed during the milk ejection: the alveoli and myoepithelial cells. Myoepithelial cells surround the alveoli and is compressed by the hormone Oxytocin to help allocate milk. Yet, because myoepithelial cells take 1-6% of the volume of breast compression, according to the assumptions, should have a negligibly small effect on the capacitance. The number m is Loka in the channels between the alveoli and the nipple is approximately 10 ml, slightly compared to the alveoli, which can store approximately 200 ml. Thus, to a good approximation, the dependence of the electrical capacity of the average volume of the alveoli can be considered linear. Additional considerations on the relation between the electric capacity and the average volume of the alveoli, see "Examples" below (see Example 1).

Now with reference to the drawings, FIG.1 and 2 shows a structural diagram illustrating a method suitable for controlling the quantity of milk consumed by the baby that is breastfed, according to various illustrative options for the implementation of the present invention.

You must understand that, unless otherwise specified, the following operations can be performed simultaneously or sequentially in many combinations or orders of execution. Specifically, the order of block diagrams should not be considered limiting. For example, two or more steps of the method specified in the following description or in the structural diagram in a particular order, can be performed in a different order (for example, in reverse order) or essentially simultaneously. In addition, several steps of the method described below are optional and may not be executed.

The method begins at position 10 and, optionally, continues to position 11, in which, when the capacity of the chest is measured during breastfeeding. The capacitance can be measured using any measuring device known from the prior art. Preferred methods of measuring electrical capacitance according to some variants of implementation of the present invention are presented below. In some embodiments, the implement position 11 is not performed. In these embodiments, the implementation of the method preferably receives data on electrical capacity from an external source.

The method continues until position 12, in which the change in electrical capacitance during breastfeeding. The method continues until position 13, in which changes in electrical capacitance correlated with the amount of milk consumed by the baby. In some embodiments, implementation of the present invention the method continues to position 14 in which the ratio of correct using the historical data collected during previous sessions of breastfeeding. Historical data may include data on electrical capacity, and/or data on the quantity of milk and/or data related to the intervals between successive sessions.

Historical data can be used in a variety of ways. In some embodiments, implementation of the present invention the historical data used for calibration. In some Islands Ianto implementation of the present invention averages received in multiple sessions are used to improve the accuracy of the amount of extracted milk for some time. In some embodiments, the implementation of historical data used to estimate the absolute content of milk in the breast, for example, by comparing the current value of the electric capacitance or its derivatives with minimal electrical capacity from historical data. By choice, this assessment is based, at least in part, on the intervals between successive sessions and/or on the procedure used for measuring the electrical capacitance in the previous sessions (for example, the location of the electrodes, and so on).

The method ends in position 15.

FIG.2 is a structural diagram of a method in the variants of implementation, in which the quantity of milk is correlated with the electric capacity and electric resistance of the chest. The method begins at position 10 and continues until position 21, which receive the electrical capacity, and to position 22, which receive the electrical resistance R. the Method can be measured and/or R directly or receive data on electrical capacitance and/or resistance from external sources. Then the method can continue until the position 23, in which the method multiplies the R, to the position 24 in which the method detects changes in RC and associates them with the need to change the number of the loose connection of the milk. The advantage of using RC as measures to assess the quantity of milk is that it is in fact invariant to changes in the shape of the breast that can occur during a breastfeeding session.

In some embodiments, implementation of the present invention to breastfeeding session is preceded by a calibration measurement, shown at position 20, which perform to collect calibration data. In these cases the implementation is correct RC using the calibration data, and the amount of milk correlated with the adjusted value RC. The preferred calibration procedure according to some variants of implementation of the present invention set forth below.

In some embodiments, implementation of the present invention, the method adjusts the value of using historical data (e.g., capacitance, resistance, amount of milk, the intervals between consecutive sessions), collected during previous sessions of breastfeeding, as detailed above. The method ends in position 15.

In various illustrative embodiments of the invention the measurement of electrical capacitance is performed at a frequency less than 100 MHz, preferably from about 1 kHz to 100 MHz, more preferably AP is sustained fashion from 1 KHz to 10 MHz, more preferably from about 1 kHz to 1 MHz, or from about 1 kHz to 100 kHz, or from about 10 kHz to 100 kHz. The advantage of this variant implementation is that at low frequencies the intracellular fluid of the breast behaves mainly as ionic solution and not as a dielectric, and the rest of the insulator remains in the thin membranes in the chest and on the skin. In some embodiments, implementation of the present invention the measurement of electrical capacitance performed to determine the electrical capacity within the breast or subtraction to minimize the contribution of the skin in electric capacity. The change in electrical capacitance of the internal breast tissue is due to changes in the amount or form of biological dielectric and therefore it is better correlated with the amount of milk in the breast.

Below is a description of several methods of measuring electrical capacitance of the breast according to various illustrative options for the implementation of the present invention.

In some embodiments, the implementation of the measure includes passing an electric current through the skin and internal breast tissue and the sample response voltage from the skin. This can be done using a number of electrodes attached to the skin of the breast. In these embodiments, electrical capacity and, optionally, electrical wiring in the practical resistance of the breast is determined on the basis of the phase voltage sample.

In FIG.3 shows a schematic illustration of a configuration that can be used according to some variants of implementation of the present invention for measuring phase. FIG.3 illustrates an implementation option, in which the applied configuration of the four electrodes, but you should understand that the number of electrodes may be different from four. In other illustrative embodiments of the invention use at least four electrodes.

In FIG.3 shows four electrodes 30-1, 30-2, 30-3 and 30-4, attached to the skin of the breast 32 and electrically connected to the block 36 of measurement of electric capacity using four wires 34-1, 34-2, 34-3 and 34-4, respectively. The electrodes can be formed on the pad or chip or combined with an overlay or chip (not shown, see, for example, FIG.6), which can be attached to the skin or to the bra for breastfeeding (for example, to petercam bra). For pressing the electrodes to the skin can be applied clamping mechanism, such as arcs, foam or springs.

One pair of electrodes (e.g. electrodes 30-1 and 30-4) may serve as a pair of current, which supplies alternating current to the skin, and another pair of electrodes (e.g. electrodes 30-2 and 30-3) may serve as a pair of voltage, which selects the voltage from the skin. The electrodes in pairs, the voltage is preferably buffered by amplifier 38 with high input impedance. Preferably, the input impedance of the amplifier 38 is at least 100 Mω or at least 1 Gω to provide a sample voltage with minimal current or no current.

The preferred location of the electrodes on the chest is the upper part of the chest, approximately 4-8 cm above the nipple. The benefit of choosing this location is that this part of the breast is usually flat, and its geometry does not change significantly during milk ejection. The electrodes can be located on the cover plate (not shown, see FIG.6), which can be sticky for quick attachment of electrodes to the skin.

The amplitude of the transmitted electrical current is preferably approximately from 0.05 mA to 0.5 mA. The amplitude of the signal supplied to the pair of current may vary depending on the quality of electrical contact between the electrodes and the skin. Usually more good electrical contact reduces the amplitude of the supplied signal. For example, when using bare electrodes with uniform conductivity signal with amplitude scale 1-5 can be a couple current to generate the desired current.

Electrical contact between the electrodes and the skin can be amplified than decreases the amplitude of the signal, which generates a current transfer. Enhanced electrical contact on agchat tracking voltage potential surfaces deep under the skin, keeping these options implementation to measure the change in electrical capacitance of the fabric of this part of the chest, which contains the mammary alveoli. The electrical contact may be enhanced by use of any method of enhancing the contact, known in this field.

In some embodiments, implementation of the present invention apply conductive gel electrodes. You can use gel, commonly used for the electrodes of the electrocardiograph. This gel penetrates into the epidermis of the skin and creates sufficient electrical contact with the tissue under the skin. The contact surface of the electrodes can be manufactured, for example, AgCl, which electrochemically reacts with the gel and increases the electric current. This alternative implementation is particularly suitable for low frequencies, for example below 20 KHz. In some embodiments, implementation of the present invention apply the gel or hydrogel electrodes on the metal (e.g. stainless steel) electrode surface. The reverse side of the electrode may be a conductive layer made by the method of screen printing. This alternative implementation is particularly suitable for frequencies from approximately 20 kHz to 1 MHz. Using gel electrodes is also an advantage from the point of view of uniformity of measurements because it sijaitseville passing current from the pressure of the electrode on the skin. If you apply the gel to the electrodes, the signal swing amplitude of approximately 0.5 V can be enjoyed on a couple of current to generate the desired current.

In some embodiments, implementation of the present invention, the surface of the electrode has a conductive protrusions or teeth. After pressing the surface of the skin electrical capacitance of the skin increases, this facilitates the transfer current in the tissue under the skin. Short teeth can penetrate the outer dead layers of the skin (stratum corneum) and to simulate the function of gel electrodes without the use of liquid or gel. If the surface of the electrode has a conductive protrusions or teeth, the signal swing amplitude of approximately 0.5 V to 1 V can be enjoyed on a couple of current to generate the desired current.

Electric similar configuration with FIGS.3 shown in FIG.4 and 5. You must understand that in FIG.4 and 5 shows a simplified scheme, which should not be considered to limit the present invention. Component values in FIG.4 shows typical results of the measurements of the chest at frequencies from about 10 to 100 KHz with ball electrodes, pressed against the skin.

The alternator sends alternating current through the wires 34-1 and 34-4 through the skin into the inner breast tissue. The amplitude and phase of the transmitted current is measured by sampling the current through will take the form of further devices. The amplitude and phase of the voltage of the internal breast tissue measured by sampling the voltage using a measuring device with wires 34-2 and 34-3. Without being bound to any theory, internal tissue model (see FIG.5) as an equivalent resistor Rbdue to electrochemical (ionic) conductivity using intracellular water in parallel with a resistor Ra and a serial capacitor Candbecause of the conductivity offset through the membranes of the alveoli. The current passing through the internal tissue model using a conductor with a low resistance (approximately 10 Ohms) (see FIG.3). The skin is modeled as having a much greater resistance than fabric and high electrical capacity.

Electric capacity and, optionally, the electrical resistance of breast tissue can be calculated using the obtained values of voltage and current. More specifically, the capacitance can be calculated from the capacitive impedance Zcapdefined as i(ε/I)/sinΔφ, using the relationship Zcap=1/(iωC), where I is supplied with current, ε is the received voltage, Δφ is the phase difference between e and I, I2=-1, ω=2πf and f is the frequency of the signal. In the embodiment, in which the quantity of milk are correlated with R and C, the result of multiplying the RC can be calculated using the relationship:

|Zres||Zcap|=|R1/iωC|=ωRC,

where Zresis the measured resistance, defined as (ε/I)/cosφ.

Knowing the amount of current it can also be used to determine the pressure of dry electrodes on the skin. The electric resistance and electric capacity is slightly dependent on the current and pressure of the electrodes on the skin. In the measurement using the four wires of the balance (the difference between the parties) pressure between dry electrodes slightly modifies the results of electrical capacity. For tracking balance can be applied the following procedure. Current-carrying wires on a time switch. Current is passed once between the right pair of electrodes and one times between the left pair of electrodes, and two current values are compared. If the current value is approximately the same (e.g., within 10%), the pressure can be considered balanced.

In the variants of implementation, in which breastfeeding is preceded by a calibration measurement, the calibration can be expressed as the ratio between RC and measurement parameters. Ethipramine include, without limitation of the current, I, DC offset, εdcand the balance between the two sides of the structure of the electrodes, I1/I2where I1current, measured with a transmission of a signal between, for example, electrodes 30-1 and 30-2, and 12 - current, measured with a transmission of a signal between, for example, electrodes 30-3 and 30-4. For example, the calibration may include setting process, for example, according to the relation;

C/C0=(I/I0)a1dcdc0)a2(I1/I2)a1,

where a1and2and a3- customizable settings, and With0, I0and εdc0- average values during calibration. After setting up a1, a2and a3you can start breastfeeding, and the amount of milk can be correlated with the number (I/I0)a1dcdc0)a2(I1/I2)a1RC, referred to below as (RC)comp. The calibration parameters are preferably chosen so as to reduce fluctuations (RC)compin terms of percentage error.

In various illustrative embodiments of the invention the electrical capacity and, optionally, the electrical resistance is measured at several frequencies. In these embodiments, the implementation of the signal, which generates an electric current is passed, preferably is superimposed waveforms of oscillations soglashatelstva frequency at which sampling is done. The amount of milk can be estimated based on a combination of measured values and the choice of RC for each individual frequency.

For example, suppose without loss of generality that the raw data obtained at two frequencies, where each frequency data are expressed as the resistance R and the capacitance C, which is obtained from the integrated value of current I and voltage ε according to:

Iε=IR+iωC.

On the other hand, in the three-component electric model of the breast (see FIG.4) components interpret using the relationship:

Iε=1Rb+11/iωCa+Ra.

We further assume, without loss of generality that the ratio between the two frequencies is equal to 2. Denoting the values of resistance and capacitance for higher frequencies as R and C, and the values of resistance and capacitance for lower frequencies as R1/2and C1/2you can get suitable measures using the following formula:

RaCa=1ω-1+3/(4C/C1/2-1),

and

RbRa=[43ω2RaCa(1RC-1R1/2C1/2)-1]-1.

In experiments performed by the authors of the present invention, it was found that the ratio Rb/Raapproximately proportional to RC. This attitude also approximates the ratio of the cross sections of the alveoli and the rest of the tissue and therefore can be used according to some variants of implementation of the present invention to search for in the breast areas that are occupied by large clusters of alveoli compared with other areas.

In experiments performed by the authors of the present invention, b is lo detected, what quantity of milk can be correlated with the following quantity:

Δ(R1/2C1/2)R1/2C1/20.5RaCa0.4(RaCa)0.1,

where the symbol <> denotes the average value of the historical data (RaCaand R1/2C1/2in this example), collected during several previous sessions of breastfeeding, and the symbol Δ denotes the difference between the value of R1/2C1/2that measured before breastfeeding, and a value of R1/2C1/2that measured after breastfeeding. In some embodiments, implementation of the present invention one or more averages of historical data replaced with the specified values.

The total amount of milk consumed by the child, may also be correlated with the following normalized from what emeniem in electric capacity:

ΔC=C1-C2C1,

where C1- electric capacity before feeding and2- electric capacity after feeding.

In some embodiments, implementation of the present invention to breast attach two or more sets of electrodes (for example, four or more electrodes in the set), and apply the technique of multiplexing between sets and between the electrodes in sets to improve the accuracy of estimates of milk. This alternative implementation is shown in FIG.3V. A number of electrodes shown in General at position 30, in contact with the breast 32 and are connected via a number of connecting wires, shown in General at position 34, controller 40 in block 36. For simplification in FIG.3B is not shown unique reference symbol for each electrode and each of the connecting wires. Also shown are just some of the connecting wires, but the expert knows how to connect the electrodes to the controller 40 with the microprocessor. The controller 40 is preferably configured to perform multiplexing by time division between the various electrodes. Cycle mule is replacerange includes two or more paced sub-cycles, and in each subcycle controller 40 selects another set of electrodes, and the unit 36 performs the measurement using the selected set of electrodes. In some embodiments, implementation of the present invention, the controller 40 selects four electrodes in subcycle. In these embodiments, the implementation unit 36 performs measurement using four wires, as detailed above, and two electrodes serve as a pair of current in the corresponding cubicle and two electrodes serve as a pair of voltage at the corresponding subtitle.

The use of multiplexing reduces the effect of local disturbances (for example, when the electrode is close to the blood vessel or heterogeneity of another type) in the measurement. Data collected from several sets of electrodes, can also be used to determine a suitable location for the insertion of the electrodes in future sessions. This can be done, for example, by avoiding places where the collected data (for example, the values of RC or Rb/Rain essence differ from data collected in other places.

Multiplexing between different pairs of electrodes of the voltage and current may contribute to the selective sensitivity at different depths in the breast tissue. Selective sensitivity may be based on different principles is ipah analysis, for example, the principles used in electroelastic tomography. Such analysis can be performed on the changes in the capacitive impedance related to the secretion of milk obtained from different combinations of electrodes. For example, the values of Δlog(C) (the difference in the logarithm of the electrical capacitance before and after breastfeeding two or more combinations of electrodes can be summarized with the corresponding sensitivity coefficients. The result can be reconstructed value Δlog(C) at a specific depth in the tissue. Thus, this method allows you to get a reaction from areas in the chest, in which many of the mammary alveoli, and get their change in electric capacitance due to the release of milk in the same way as processed one impedance measurement. In some embodiments, implementation of the present invention is the total rate of milk production is taken into account when mapping a measured quantity or combination of quantities with the quantity of milk. This alternative implementation is particularly suitable when the session of breastfeeding is relatively long (e.g. more than 30 minutes). The average rate of milk production (approximately 30 ml per hour) can be multiplied by the duration of breastfeeding and added to the change in the volume of milk in the breast.

In FIG.6 schematically shows a variant Khujand the exercise of, which unit of measurement of electrical capacitance includes a cover plate 60, with two or more electrode 64-1 and 64-2 to monitor changes in electrical capacitance of the breast 32. The electrodes 64-1 and 64-2 can be connected with the circuit 62 for measuring the electrical capacitance, for example, using the shown two-wire connection. Although in FIG.6 shows the arrangement of two electrodes in the plate 60, this is not necessarily so, because the cover plate 60 may include more than two electrodes. Also, the strap 60 can be connected with the scheme with any number of wires, which may differ from the number of electrodes in the plate 60. For example, the cover 60 may include four electrodes, which are connected in pairs and connected with the circuit 62 via a two-wire connection. One such configuration similar to the configuration shown in FIG.3, except that the electrode 30-1 is connected to the electrode 30-2, and the electrode 30-3 is connected to the electrode 30-4.

The plate 60 may be adhesive to facilitate attachment of the pads to the chest. Also provided by the overlay, which contains two detachable parts, and at the end of the session breastfeeding one part of the lining is cut off, and the other part remains on the breast to mark the place for the insertion of the electrodes in the following session. At the beginning of breastfeeding Marche is the main part of the lining can be detached, in order not to interfere with breastfeeding after installation of the lining.

The overlay can also be not sticky. In this embodiment, the cover 60 can be installed on a bra for breastfeeding (e.g., bra straps), and other Installation preferably carried out so that the pad was pressed, for example, the clamping mechanism, such as a soul, foam or springs, to the skin, but with minimal deformation or no distortion of the breast shape. For example, pad and installation mechanism can be made adjustable along the contour of the breast.

The electrodes in the cover plate 60 may, if desired, to be or not to be in electrical contact with the skin. The configuration in which the electrodes are in contact with the skin, preferred from the viewpoint of a strong signal, whereas the configuration without contact preferred from the viewpoint of convenience for the mother, breastfeeding. You need to understand that the values of electrical capacitance is measured without contact with the skin less sensitive to the action of the current, but significantly lower than the values measured in direct contact with the skin, also the authors of the present invention have found that contactless configuration is quite sensitive to changes in the shape of the breast and therefore can be correlated with the amount of milk consumed by the baby.

Scheme 62 preferably sensitive to changes in electrical capacitance in subpicogram range (for example, 0.01 to 1 pF) when the electrodes are not in contact with the skin, and in nanofarad range (1-100 nF), when the electrodes are in contact with the skin. In some embodiments, implementation of the present invention, the circuit 62 includes a capacitive bridge, and in some embodiments, the implementation of the scheme 62 contains - inductive-resistive-capacitive probe. Also, there are variants of implementation, in which the circuit 62 is a device for measuring the frequency of oscillations, which detects the oscillation frequency of the transistor or amplifier using a feedback circuit using a single electrode.

In some embodiments, implementation of the present invention, the contribution of the skin in the electrical capacity is subtracted from the measured capacitance to separate the electrical capacity of the internal breast tissue, which is better correlated with the amount of milk.

The contribution of the skin in the electrical capacity can be measured in different ways. In some embodiments, implementation, shown schematically in FIG.6, the total electrical capacitance measuring circuit 62, and the electric capacity of the skin is measured by the circuit 66 measuring the electrical capacitance of the skin, which differs from the circuit 62. The circuit 66 may be used, for example, Trekhprudny the second method of measuring electrical capacitance, such as one of the methods disclosed by Rosella and others (Rosell et al) in an article published in IEEE. trans. Biomed. Eng 35 (8), 649 (1988), the contents of which are incorporated herein by reference. In some embodiments, the implementation, the contribution of the skin in electric capacity estimate based on the thickness of the skin. Skin thickness can be obtained as data from an external source or it can be measured. Non-invasive methods of measuring the thickness of the skin is known in this field. In some embodiments, the implementation of the thickness of the skin is measured by the oximeter, which emits infrared radiation in the direction of the skin and detects the reflected light intensity according to the distance from the blood, which diffuses the light. The measured distance is the thickness of the dry layer of the skin.

Now with reference to FIG.7, which is a schematic illustration of a system 70 controls breastfeeding according to various illustrative options for the implementation of the present invention. The system 70 may be used to perform any of the operations described above and shown in the structural diagram with FIG.1 and 2.

The system 70 includes the unit of measurement of electrical capacitance 72, adapted for measuring changes in electrical capacitance of the breast during breastfeeding, and the processing unit 74 to correlate changes in electrical capacitance with the quantity of the milk, consumed by the child is breastfed. The block 74 is preferably a digital processing unit. The unit of measurement of electrical capacitance 72 is preferably configured to measure the electrical capacitance inside the chest with the subtraction of the contribution of the skin in electric capacity. For example, the block 72 may have a number of electrodes connected to the skin of the breast (not shown, see FIG.3 and 6), as detailed above. In various illustrative embodiments of the invention, the block 72 determines the capacitance based at least in part, the phase response of the voltage, as detailed above. The system 70 may also contain a unit of measurement of resistance 78, which measures the electrical resistance of the chest, as detailed above. The processing unit 74 may compute the result of multiplying the RC and to correlate the quantity of milk with a value of RC, as detailed above. In various illustrative embodiments of the invention, the system 70 includes a controller 40, which performs multiplexing by time division between the electrodes, as detailed above.

Unit 74 may be configured to perform any of the operations described above calculations to improve the accuracy of the correlation. For example, in some variations the tah implementation unit 74 combines measurement, carried out at different frequencies, in some embodiments, the implementation unit 74 calculates the calibration factor, in some embodiments, the implementation unit 74 corrects the correlation using historical data collected in previous sessions of breastfeeding, in some embodiments, the implementation of block 74 analyzes the measurements made in different paced sub-cycles cycle multiplexing to determine the most appropriate measurement in future sessions and/or in order to discern the sensitivity of measurements at different depths in the breast, etc., In various illustrative embodiments of the invention, the system 70 includes the environment memory 76 for storing historical data. Environment memory 76 preferably is a medium of non-volatile memory.

In some embodiments, implementation of the present invention, the processing unit 74 is configured to subtract the contribution of the skin in electric capacity. In such scenarios, the implementation of the unit of measurement of electric capacity 72 preferably has a circuit for measuring the electrical capacitance of the skin and the circuit for measuring the total electrical capacitance of the skin, as detailed above. The system 70 may also contain a device for measuring the thickness of the skin 80, which measures the thickness of the skin, as detailed above. In this variant implementation, the program processing unit 74 receives the data by the thickness of the skin from the device 80 and evaluates the contribution of the skin in electric capacity based on thickness.

The system 70 may also include block UI 82 and/or the display 84. The user interface 84 may be configured to receive user input, for example, the beginning and the end of breastfeeding. The display 84 may be a miniature display, mounted in the same housing unit 74. Display 84 displays the results of the monitoring. The display can show the progress of the milk during breast-feeding, for example, in diagram form. At the back end of the display 84 may display the amount of milk consumed.

It is expected that during the term of a patent obtained by this application will be developed a many appropriate ways to measure the electrical capacitance, and the scope of the term "device for measurement of electric capacity" is intended to include all such new technologies a priori.

Used herein, the term "about" refers to ±10%.

Used here the word "illustrative" means "serving as an example, an incident or illustration". Any variant of implementation, defined as "illustrative" should not necessarily be construed as preferred or having an advantage over the other options in the implementation and/or exclude the presence of elements of the other options assests the deposits.

Used herein, the term "select" means "referred to in some embodiments, implementation and not provided for in other variants of the implementation.

Any particular implementation of the invention may include a number of signs of "choice", if such signs do not contradict each other.

The terms "includes", "include", "includes", "including", "having" and their cognates mean "including, but without limitation".

The term "comprising" means "including and limited to anything".

The term "consisting essentially of" means that the composition, method or design may include additional ingredients, steps and/or parts, but only if such additional ingredients, steps and/or parts not materially alter the basic and novel characteristics of the proposed composition, method or design.

Used herein, the term "connection" or "at least one connection may include several compounds, including mixtures thereof.

In the text of this proposal, various embodiments of the present invention can be presented in the format range. It should be understood that the indication in the format of the range given merely for convenience and brevity and should not be construed as an inflexible limitation of the scope of the invention. Accordingly, an indication of what the range should be considered revealing all possible subranges, as well as individual numerical values in this range. For example, specifying a range from 1 to 6 should be considered specifically revealing the subranges from 1 to 3, 1 to 4, from 1 to 5, 2 to 4, from 2 to 6, from 3 to 6 and so on, as well as individual numerical values in this range, such as 1, 2, 3, 4, 5 and 6. This applies regardless of the width of the range.

In the case here the numeric range that means it includes any specified number of (fractional or integer). The phrase "ranging from... to..." indicates the first number and the second number, and the words "in the range from the first specified number "to" second specified number are used herein interchangeably and mean "including first and second indicated numbers and all the fractional and integer numbers between them."

You must understand that certain features of the invention, which for simplicity is specified in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which for simplicity is specified in the context of one possible implementation may also be provided separately or in any suitable combination in any other described embodiment of the invention. Certain features described in the context of various embodiments, and should not be considered a significant sign of these embodiments, if only this variant implementation without these elements does not work.

Various embodiments of aspects of the present invention described above and claimed in the claims, have experimental support in the following examples.

EXAMPLES

Now, reference is made to the following examples, which together with the above descriptions illustrate some embodiments of the invention permissive way.

EXAMPLE 1

A computational model of

In this example, there are additional considerations regarding the relationship between the electric capacity and the average volume of the alveoli, without reference to any specific theory. The following is based on a computational model, which is not intended to limit the scope of the present invention in any way.

In FIG.8 presents a simplified diagram of the alveoli, which is compressed during milk ejection. For simplicity the socket represented as a flattened body, which is compressed at axis C.

The average cross-section of one flattened body in an arbitrary orientation can be calculated [Vickers and brown (Vickers and Brown), Proc. R. Soc. Lond. A, 457, 283] as follows:

<σ1>=πa22 πac2sinh-1ee,

where e is the ellipticity of the flattened body, defined as e=(12/a2)0.5and a - half larger diameter flattened body (and>). The right member of the <σ1> is almost constant and equal to 0.88.

The volume of the flattened body is equal to:

V1=4πa2c/3.

When flattened body then collapses, and approximately constant, and the volume is proportional towithno perceptible change in the flattened region (the flattened surface of the body are not flexible in order to accommodate the change in volume of milk).

Assuming a uniform density of alveoli, n, milk volume V can be correlated with the volume of the alveoli, V1:

V1=VnVbreast,

where Vbreasteffective volume of the breast.

The electrical capacity of numerous alveoli in a discrete volume can be estimated by counting the alveoli, as if they were layers of one of alveoli in each position (see FIG. 9). This layer area of Asampdetermines the total cross with the increase of alveoli < σ>:

<σ>=<σ1>n2/3Asamp

that can be written as:

<σ>=πa22n2/3Asamp+0.8838aAsampVbreastn-1/3V.

Full electrical capacity because of the alveoli is taken between the potential surfaces of the separation distances Lsamp:

Calv=ε0εr<σ>Deff,

where Deff- the effective width of only an insulating material between the potential surfaces. Thus, in this computational model all electric capacity sequentially added to a single capacitor with an effective thickness of the insulation layer. Because each layer of the alveoli cross-section of the insulating behavior of the displacement is equal to 4 membranes with thickness d (two sides of the cells on the two sides of the alveoli, which form its shell), total effective membrane can be calculated as:

Deff=4d(n1/3Lsamp).

Thus, the total electric capacity can be written as:

Calv=(AsampLsamp)(ε0εrd)n1/3[πa28+0.88332aVN],

where N=nVbreastthe number of alveoli in the breast.

Without being bound to any theory it can be assumed that, on average, N, a and d have values that are universal for most women, otherwise breastfeeding would be either too difficult for the child, or the milk would stand out spontaneously. The density n, the amount of fat in the chest and the shape of the breast can affect the value for a given amount of milk V.

EXAMPLE 2

Monitoring of breastfeeding using a 4-wire configuration

Ways

60 session allocation m is Loka was attended by 11 nursing mothers, and they were pumped milk or gave it to their children more than 45 ml. Quantity of milk in the case of pumping was measured according to the level of the milk in the bottle during several intervals of approximately 1/2 minutes in milk, and in the case of feeding of the child according to the child's weight before and after feeding. The accuracy of the first method was 5 ml and the second 10 ml Density of pumped milk regularly checked, and we can assume that she was 1 g/ml (with an error of up to 7%).

For control used 4-wire method of impedance AC. Four electrodes for pediatric ECG (company ConMed Huggables 1620-003) placed on the upper chest in a constant for each patient (±1 cm), 6-7 cm above the nipple. The internal electrode voltage were spaced 65 mm, and the outer electrode current put another 30 mm from the electrode voltage. Discrete signal was in the form of waves 0.5 sin(ωf)+0.5 sin(0.5 ωt) V (t - time), where ω=2πf and f=50 kHz.

The waveform was generated with the help of the device to National instruments USB-6251 with analog output on the update frequency of 2.5 MHz, setting the differential amplifier INA117 as a buffer. This oscillating voltage is connected with one electrode of the pair of current, and the other electrode of the pair of current connected to ground through resistor 301 Ohm (0,1%), which was used for vyborgite according to the difference voltage across the resistor. Each electrode of a pair of voltage amplified using amplifier LT1793 Jfet and carried out sampling analog-to-digital feature card receipt N1 USB-6251.

The voltage sampling ε was based on the difference between the voltage outputs of the two amplifiers. The current and voltage of the sample was passed through a fast Fourier transform of the size of the pot one-second data at a sampling rate of 1 MHz. Found peaks at each test frequency, and the phase and amplitude of current and voltage after Fourier transforming in the resistance R and the capacitance C in parallel model based on the following equation:

Iε=1R+iωC

Results

The results of electric capacity, the result of multiplying the RC to a higher frequency (50 kHz) and low frequency (25 kHz) and the ratio Ra/Rbas a function of the consumption of milk is shown in FIG.10-13, respectively, for a single experimental session. With expressed nanofarad (FIG.10), RC in nanoseconds (FIG.11 and 12) and the ratio Ra/Rbis dimensionless (FIG.13). The amount of milk expressed in milliliters. The results of another experimental session for another patient shown in FIG.14-16 (n is a frequency of 50 kHz).

In a representative experimental session is shown in FIG.11-13, used the following Protocol: 5 minutes of rest (i.e., without pumping or breastfeeding), 10 minutes of pumping (from 6 minutes to 15 minutes) 4 minutes of rest (from 16 minutes to 19 minutes), 5 minutes of breastfeeding (from 20 minutes to 24 th minute and 2 minutes of rest (from 25 minutes to 26 minutes). During the period of pumping was evacuated 70 ml, and 40 ml fed during the breastfeeding period. The other breast was also controlled during all 26 minutes, but the milk was not allocated. Each point in FIG.10-13 are based on the average of 10 consecutive samples R and S, and the standard deviation was calculated from 10 samples. Points with a standard deviation of more than 2% from the average value were not taken. Stability was approximately 0.2 to 1%. Curves of RC as a function of the volume of milk consumed (FIG.11 and 12) was calculated based on the last two points immediately before milk ejection and the first two points immediately after stopping for milk. Curves were studied to determine the scaling between the allocation of milk and electrical measurements.

Electric capacity showed a decrease from the initial value of 9.5 nF to nF 7,7 by reducing the amount of milk in the alveoli of the breast (FIG.10). A linear dependence of resulttaurine RC was observed for higher (FIG.11), and lower (FIG.12) frequencies. Similar behavior was observed in all the other sessions. The slope of the curve Δ(RC)1/2/ΔV in this representative session was approximately -1,05 NS/ml. the Value of RaCachanged only a little during the whole session (RaCa=4520±80 NS).

The results of additional experimental session is shown in FIG.14-16. In FIG.14-15 shows the capacitance against time and against the release of milk during breast-feeding, and in FIG.16 shows the change in the electrical resistance. In FIG.14-16 diamonds shows the results of measurements before and after the child touched his chest, and dots show the measurement results when the baby is sucking (the latter on the axis of milk ejection assumes a constant speed feeding). Grabbing the child breast modifies the geometry and thus changes the capacitance and resistance; however, resistance increases and the capacitance decreases as compared with the line between stable measurements, therefore, the values of RC break for grasping the child should decrease. Note that during the allocation of 160 ml of the capacitance value decreases by more than 40%, while the change in resistance is much smaller in relative numbers (in other e is sperimentali sessions, the resistance change is not correlated with the secretion of milk).

Discussion

The standard deviation curves Δ(RC)1/2/ΔV obtained for 60 sessions was approximately 25% from the average curve. After the correction Δ(RC)1/2using historical data curves showed a decrease in the standard deviation of 23.5% from the average value. The following formula was used to correct Δ(RC)1/2:

Δ(RC)1/2R1/2C1/20.5RaCa0.4(RaCa)0.1

FIG.17 is a histogram curves after correction, where the average slope of the curve is scaled to 100%. 72% of values are within error of 20% in the slope of the curve about the mean. The difference in percentage relative to 100% can be interpreted as the error in the forecast of change of the volume of milk on the basis of electrical measurements with this setup. The average slope value crooked is after the correction can be used to determine changes in the volume of milk using the settings as a control for breastfeeding.

This experiment demonstrated that, given the average slope of the curve measurement in accordance with some of the options for implementation of the present invention, the difference in Δ(RC)1/2and the initial values of RaCaand (RC)1/2allow to predict the amount of milk consumed with the accuracy of 23.5% for any woman.

EXAMPLE 3

Control of breastfeeding using a contactless configuration

The amount of milk consumed by the baby during breast-feeding was controlled by measuring the electrical capacitance between two electrodes placed on the chest, but not in electrical contact with them during the breastfeeding session.

In FIG.18 and FIG.19 shows the raw data signal electric capacitance in pF as a function of time in arbitrary unit during one session of breastfeeding. A continuous change in electric capacitance was observed during the whole session. The observed change in electrical capacitance interpreted as representing the quantity of milk consumed by the baby during breastfeeding.

The amount of milk can be correlated with the following normalized change in electric capacitance:

ΔC=C1 -C2C1

where C1- electric capacity before it is needed, and C2- electric capacity after feeding.

Although the invention has been described in connection with specific variants of implementation, it is clear that for specialists in this field will be obvious, many alternatives, modifications, and changes. Accordingly, it is intended to embrace all such alternatives, modifications and changes that fall within the nature and broad scope of the attached claims.

All publications, patents and patent applications mentioned in the present description, is included in full by reference in the description, as if each individual publication, patent or patent application was specifically and individually indicated as incorporated herein by reference. In addition, the mention of any reference in this application shall be construed as an admission that such reference was available in the prior art to the present invention. To the extent that uses section headings, they should not be construed as necessarily limiting.

1. The method of controlling the quantity of milk consumed by the baby breastfeeding, including the identification of changes in the cleverly is possible measure the electrical resistance of the chest to measure the electrical capacitance of the breast before and after breastfeeding, and correlate these changes will be mentioned in the result of the multiplication with the amount of milk consumed by the child.

2. The method according to p. 1, characterized in that subtract the contribution of the skin of the breast in the above-mentioned result of the multiplication.

3. The method according to p. 1, characterized in that the above multiplication is measured using a number of electrodes, and those that used at least one cycle multiplexing to various paced sub-cycles of the said series of multiplexing used a different set of electrodes for measuring the above-mentioned result of the multiplication.

4. The method according to p. 3, characterized in that the values of the multiplication results measured during at least one of the above-mentioned cycle multiplexing, are used to determine the measurement on the chest in future sessions.

5. The method according to p. 3, characterized in that the values of the multiplication results measured during at least one of the above-mentioned cycle multiplexing, analyze, to differentiate the sensitivity of measurements at different depths in the chest.

6. The method according to p. 1, characterized in that the mentioned changes are determined on the basis of the phase voltage, selected on the skin of the breast in response to electric current applied to the said skin.

7. The method according to p. 6, characterized in that the mentioned changes are measured using at least four electrodes connected to the skin of the breast./p>

8. The method according to p. 1, characterized in that the result of the multiplication is adjusted on the basis of the calibration data collected before mentioned breastfeeding.

9. The method according to p. 1, characterized in that the result of the multiplication is determined for each of several frequencies and the amount of milk correlated with a combination of at least two results of the multiplication.

10. The method according to p. 1, characterized in that the mentioned changes are measured, at least in part, using at least one device selected from the group consisting of a capacitive bridge, inductive-resistive-capacitive probe and device for measuring the oscillation frequency.

11. Control system breastfeeding containing the unit of measurement of electric capacity, adapted for measuring changes in electrical capacitance of the breast before and after breastfeeding, block resistance measurement to measure the electrical resistance of the chest and a processing unit which is connected with these blocks and configured to compute the result of multiplying the electric resistance electric capacitance and correlating the results of the multiplication with the amount of milk consumed by the baby breastfeeding.

12. System on p. 11, characterized in that the said measurement unit with whom holds a number of electrodes, connected to the skin of the breast so as to measure the contribution of the internal breast tissue in the above-mentioned electric capacity by subtraction of the contribution of breast skin in the above-mentioned electric capacity.

13. System on p. 11, additionally containing environment memory for storing historical data collected in previous sessions of breastfeeding, characterized in that the said processing unit configured to correct the above-mentioned correlation using the historical data.

14. System on p. 11, characterized in that the said electrical capacity adjusted on the basis of the calibration data collected before mentioned breastfeeding.

15. System on p. 11, characterized in that the said electrical capacity is determined for each of several frequencies, and the fact that the quantity of milk are correlated with a combination of at least two measured values of electrical capacitance.

16. System on p. 11, characterized in that the said measuring units contain at least one device selected from the group consisting of a capacitive bridge, inductive-resistive-capacitive probe and device for measuring the frequency of oscillations.



 

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2 ex, 1 dwg, 1 tbl

FIELD: medicine.

SUBSTANCE: method involves measuring an enamel electrical conductivity and assessing a light-induced fluorescence of a dental tissue in the lesion. A current intensity within the lesion of no more than 0.2 mcA and the absence of the enamel glow testify to the enamel intactness with zero points assigned. The current intensity of 0.21 to 1.99 mcA and the enamel glow testify to the preclinical enamel changes with 0.1 points assigned. The current intensity of 2.0 to 3.99 mcA and the enamel glow testify to primary caries changes at the stage of dead spot with 0.4 points assigned. The current intensity of 4.0 to 5.99 mcA and the enamel glow testify to primary caries changes at the stage of dead spot with 0.7 points assigned. The current intensity of 6.0 to 7.99 mcA and the enamel glow testify to primary caries changes at the stage of deep white spot with 1 point assigned. A dental tissue resistance index (RIdt) is calculated by formula: RIdt=(F0×0+F1×0.1+F2×0.4+F3×0.7+F4×1)/n, wherein F0 is the number of teeth with the intact enamel; F1 is the number of teeth with the preclinical enamel changes ; F2 is the number of teeth with caries enamel changes at the stage of dead spot; F3 is the number of teeth with caries enamel changes at the stage of white spot; F4 is the number of teeth with caries enamel changes at the stage of deep white spot; n is the number of intact teeth having preclinical and early clinical changes. The index is calculated prior to and after the therapeutic-preventive course. A positive difference of the indices prior to and after the therapeutic course testifies to the adequacy of the conducted therapy. The above difference being zero or less testifies to the necessity of the recurrent course or changes in the therapy.

EFFECT: method provides assessing the dental tissues taking into account the preclinical and early changes.

1 tbl, 1 ex

FIELD: medicine.

SUBSTANCE: invention refers to medicine. A device for real-time electrodermal skin activity test comprises electrodes with fasteners, an input element, a filter, the first and second dispersion evaluators, an expectation evaluator, the first and second variation coefficient evaluators, a subtractor, a threshold former, a comparator, and a counter.

EFFECT: invention provides higher reliability and accuracy of the real-time electrodermal activity and psychoemotional status test with relaxation in the hardware requirements and a possibility to separate relatively slowly varying phase components.

2 dwg

FIELD: medicine.

SUBSTANCE: arm impedance variation is recorded in the hemodynamic load generated with a patient standing by raising arms upward, keeping arms in this position and returning to a normal position and lowering along the body. A period of time of the vertical standing with the arms raised upwards makes 30 seconds. After the arms are returned to the normal position, electrical impedances are recorded 10 seconds later, and a recovery index (RI) is determined by the original formula. If RI≤1, a norm is stated, while RI>1 enables stating the presence of atherosclerotic changes, a manifestation of which is stated by an excess.

EFFECT: method enables norming the time parameters of hemodynamic load and obtaining the qualitative assessment of the functional status of the arterial blood flow to enable the early instant diagnosis of developing atherosclerosis.

3 dwg, 1 tbl

FIELD: physics.

SUBSTANCE: apparatus (1) for detecting pulse wave and breathing cycle signals of a person has two current-conducting electrodes (2, 3) to be attached to the human body, a first (4) and a second (6) operational amplifier, an amplitude detector (5), a switched frequency-dependent voltage divider (8) and a microcontroller (7). The electrodes (2, 3) are connected in the negative feedback circuit of the first operational amplifier (4). The microcontroller (7) is configured to generate a high-frequency carrier signal at the output of a first input/output port (L). The upper (10) and lower (11) arms of the voltage divider (8) are formed by two circuits, having a common end at the mid-point of the voltage divider and two separate ends. The second operational amplifier (6) and the voltage divider (8) form an active band-pass filter with upper and lower cut-off frequencies defined by parameters of the upper (10) and lower (11) arms of the voltage divider (8), respectively. The frequency response of such a filter when the second input/output port (M) of the microcontroller (7) is connected to zero potential enables signal detection in a frequency band which corresponds to the frequency band the pulse wave signal, and enables signal detection in the frequency band corresponding to the frequency band of the breathing cycle signal when the third input/output port (N) of the microcontroller (7) is connected to zero potential.

EFFECT: detecting pulse wave and breathing cycle signals of a person based on measuring the impedance of a body area using a simple non-adjustable electrical circuit.

14 cl, 12 dwg

FIELD: medicine.

SUBSTANCE: device for measuring electric parameters of an individual's body area (3) comprises two conducting electrodes (5, 6) placed on the individual's body, an operating amplifier (2) and a microcontroller (1). The microcontroller (1) is configured to operate in the mode of the individual's body area impedance measurement, in the mode of the individual's skin resistance measurement and in the mode of the individual's body area potential measurement. The electrodes (5, 6) are connected to a negative feedback circuit of the operating amplifier (2), a non-inverting terminal of which is connected to the zero potential, and an output is connected to an input of an analogue-to-digital converter of the microcontroller (1), while an inverting terminal is connected through a resistor (4) to an in/out port (L) of the microcontroller (1). In the mode of the individual's body area impedance measurement, the microcontroller (1) provides forming a signal of a pre-set frequency whereat the impedance is measured, on the output of the in/out port (L). In the mode of the individual's skin resistance measurement, the microcontroller (1) provides forming a DC voltage signal on the output of the in/out port (L). In the mode of the individual's body area potential measurement, the microcontroller (1) provides switching off the in/out port (L).

EFFECT: more accurate measurement of the electric parameters of the individual's body areas by switching the microcontroller modes without change of the electrodes and their body position.

9 cl, 12 dwg

FIELD: medicine.

SUBSTANCE: method involves carrying out urological examination for determining hydrodynamic resistance of ureter calculated from formula Z=8Lμ/(πR4), where Z is the hydrodynamic resistance of ureter, L is the ureter length, R is the ureter radius, μ is the urine viscosity. Angle α at which the ureter enters the urinary bladder is determined from formula cosα = 8l1μ/(ZπR4), where l1 is the perpendicular drawn from the upper edge of the ureter to the its exit projection line, μ is the urine viscosity, Z is the hydrodynamic resistance of ureter, R is the ureter radius. Vesicoureteral reflux recidivation is predicted when the angle of α+90° is less than 120°.

EFFECT: enhanced effectiveness in reducing the number of recidivation cases.

2 dwg, 1 tbl

FIELD: medicine.

SUBSTANCE: one should measure electric impedance of patient's middle ear. Electrodes should be applied in three localizations: auditory canal, anterior end of lower nasal concha and frontal skin. Electric impedance should be measured at the frequencies of sinusoidal signal being equal to 10, 30, 250 and 1000 Hz, the data obtained should be compared by values of electric impedance in the given area (middle ear) in the group of healthy patients. This method provides the chance to obtain comparative data for diagnostics of middle ear diseases.

EFFECT: higher accuracy of evaluation.

2 ex

FIELD: medicine; medical engineering.

SUBSTANCE: method involves doing multi-channel recording of electroencephalogram and carrying out functional tests. Recording and storing rheoencephalograms is carried out additionally with multi-channel recording of electroencephalogram synchronously and in real time mode in carotid and vertebral arteries. Electroencephalograms and rheoencephalograms are visualized in single window with single time axis. Functional brain state is evaluated from synchronous changes of electroencephalograms, rheoencephalograms and electrocardiograms in response to functional test. The device has electrode unit 1 for recording bioelectric brain activity signals, electrode unit 2 for recording electric cardiac activity signals, current and potential electrode unit 3 for recording rheosignals, leads commutator 4, current rheosignal oscillator 5, synchronous rheosignal detector 6, multi-channel bioelectric brain activity signals amplifier 7, electrophysiological signal amplifier 8, demultiplexer 9, multi-channel rheosignal amplifier 10, multi-channel analog-to-digital converter 11, micro-computer 12 having galvanically isolated input/output port and personal computer 13 of standard configuration.

EFFECT: enhanced effectiveness of differential diagnosis-making.

11 cl, 6 dwg

FIELD: medical engineering.

SUBSTANCE: device has acting upon skin between electrodes with DC potential of given magnitude for producing temporary breakdown. Skin impedance is measured between measuring electrode first negatively polarized relative to control electrode and the control electrode, and then, DC current resistance is measured once more by means of measuring electrode positively polarized relative to the control electrode. Ratio of the obtained values is used for determining internal organ health state, corresponding to skin area.

EFFECT: enhanced accuracy of diagnosis.

11 cl, 14 dwg, 2 tbl

FIELD: poultry science.

SUBSTANCE: the present innovation deals with visual evaluation in chicken followed by testing them by the value of bioelectric potential. Chickens with bioelectric potential being significantly higher against average values are considered to be stress-resistant ones and those with bioelectric potential being significantly lower against average values in concrete population are concluded to be stress-sensitive ones. The method is very simple in its implementation and efficient for large-scale selection in poultry on stress-resistance.

EFFECT: higher efficiency.

1 cl, 2 dwg, 2 ex, 4 tbl

FIELD: medicine.

SUBSTANCE: the method deals with measuring geometric body size and electric impedances of patient's hands, body and legs at their probing with low- and high-frequency current due to current and potential electrodes applied onto distal parts of limbs, and, thus, detecting extracellular, cellular and total volumes of liquid in patient's hands, body and legs. While implementing the method one should additionally apply current electrodes onto left-hand and right-hand parts of neck, and potential electrodes - onto distal femoral parts. Body impedance (Zb) should be measured due to successive measuring the impedance of its right-hand Zrb and left-hand Zlb parts at probing current coming between electrodes of similar sides of patient's neck and legs to detect Zb, as Zb = Ѕ x (Zrb + Zlb), impedance of legs Zl should be detected due to measuring femoral impedance Zf and that of shins Zs, as Zl = Zf + Zs. At detecting the volumes of liquid in body and legs one should apply measured values of Zb and Zl, moreover, as geometric body size one should apply the distance against the plane coming through the upper brachial surface up to the middle of radiocarpal articulation in case of patient's hand being along the body.

EFFECT: higher accuracy of detection.

5 dwg, 2 ex, 3 tbl

FIELD: medicine; medical engineering.

SUBSTANCE: method involves applying electrodes to injured extremity tissue under study. The electrodes are arranged in diametrically opposite points of horizontal plane transaction to extremity surface. Two electrodes are applied to the other extremity. The electrodes are arranged in diametrically opposite points of horizontal plane transaction to extremity surface. An initial point is selected relative to which pairs of electrodes are equidistantly arranged on the extremity. Active and reactive impedance components are measured at the places of electrodes positioning. Viability condition of the injured extremity tissue under study is diagnosed depending on ratio of reactive to active impedance component on injured and intact extremity and difference between reactive impedance component on injured and intact extremity. Device has transducer unit, computer and unit for processing signals having interface units, central subscriber station, autonomous transmission center, commutator which input is connected to transducer unit output and commutator output is connected to central subscriber station input, the first input is connected to autonomous transmission center output.

EFFECT: high accuracy in diagnosing biological object condition.

5 cl, 5 dwg, 4 tbl

FIELD: medicine, psychotherapy.

SUBSTANCE: the method deals with correcting neurological and psychopathological disorders with anxiety-phobic symptomatics due to individual trainings. The method includes evaluation of body reaction to stimulating signals, seances of individual training performed due to the impact of two quasiantipodal stimulating signals of similar physical modality applied in time of sporadic character, and as a signal one should present biological feedback for the altered value of physiological parameter adequately reflecting body reaction to the impact of stimulating signal. At the first stage of training it is necessary to achieve body adaptation to the impact of quasiantipodal stimulating signals, at the second stage it is necessary to obtain conditional reflex for one out of stimulating signals, for this purpose one should accompany this stimulating signal with discomfort impact, during the third stage, finally, due to volitional efforts one should suppress body reaction to stimulating signal. The devise suggested contains successively connected a transformer of physiological parameter into electric signal and a bioamplifier, an analysis and control block with a connected block to present the signals of biological feedback, a block for presenting discomfort impact, an indication block and that of forming and presenting quasiantipodal stimulating signals. The innovation enables to have skills to control one's emotions, decrease sensitivity threshold to environmental impacts and learn to how behave during stress situations.

EFFECT: higher efficiency of training.

15 cl, 8 dwg

FIELD: medicine; medical engineering.

SUBSTANCE: method involves recording multichannel electroencephalogram, electrocardiogram record and carrying out functional test and computer analysis of electrophysiological signals synchronously with multichannel record of electroencephalogram and electrocardiogram in real time mode. Superslow brain activity is recorded, carotid and spinal artery pools rheoelectroencephalogram is recorded and photopletysmogram of fingers and/or toes is built and subelectrode resistance of electrodes for recording bioelectrical cerebral activity is measured. Physiological values of bioelectrical cerebral activity are calculated and visualized in integrated cardiac cycle time scale as absolute and relative values of alpha-activity, pathological slow wave activity in delta and theta wave bandwidth. Cerebral metabolism activity dynamics level values are calculated and visualized at constant potential level. Heart beat rate is determined from electrocardiogram, pulsating blood-filling of cerebral blood vessels are determined from rheological indices data. Peripheral blood vessel resistance level, peripheral blood vessel tonus are determined as peripheral photoplethysmogram pulsation amplitude, large blood vessel tonus is determined from pulse wave propagation time data beginning from Q-tooth signal of electrocardiogram to the beginning of systolic wave of peripheral photoplethysmogram. Postcapillary venular blood vessels tonus is determined from constant photoplethysmogram component. Functional brain state is determined from dynamic changes of physiological values before during and after the functional test. Device for evaluating functional brain state has in series connected multichannel analog-to-digital converter, microcomputer having galvanically isolated input/output ports and PC of standard configuration and electrode unit for reading bioelectric cerebral activity signals connected to multichannel bioelectric cerebral activity signals amplifier. Current and potential electrode unit for recording rheosignals, multichannel rheosignals amplifier, current rheosignals generator and synchronous rheosignals detector are available. The device additionally has two-frequency high precision current generator, master input of which is connected to microcomputer. The first output group is connected to working electrodes and the second one is connected to reference electrodes of electrode unit for reading bioelectrical cerebral activity signals. Lead switch is available with its first input group being connected to potential electrodes of current and potential electrodes unit for recording rheosignals. The second group of inputs is connected to outputs of current rheosignals oscillator. The first group of outputs is connected to current electrodes of current and potential electrodes unit for recording rheosignals. The second group of outputs is connected to inputs of synchronous detector of rheosignals. Demultiplexer input is connected to output of synchronous detector of rheosignals and its outputs are connected to multichannel rheosignals amplifier inputs. Outputs of multichannel bioelectrical cerebral activity signals amplifier, multichannel rheosignals amplifier and electrophysiological signal amplifier are connected to corresponding inputs of multichannel analog-to-digital converter. Microcomputer outputs are connected to control input of lead switch, control input of multichannel demultiplexer, control input of multichannel analog-to-digital converter and synchronization inputs of current rheosignals oscillator and synchronous detector of rheosignals. To measure subelectrode resistance, a signal from narrow bandwidth current generator of frequency f1 exceeding the upper frequency fup of signals under recording is supplied. A signal from narrow bandwidth current generator of frequency f2≠ f1>fup is supplied to reference electrode. Voltages are selected and measured at output of each amplifier with frequencies of f1, f2 - Uf1 and Uf2 using narrow bandwidth filtering. Subelectrode resistance of each working electrode is determined from formula Zj=Ujf1 :(Jf1xKj), where Zj is the subelectrode resistance of j-th electrode, Ujf1 is the voltage at output from j-th amplifier with frequency of f1, Kj is the amplification coefficient of the j-th amplifier. Subelectrode resistance of reference electrode is determined from formula ZA=Ujf2 :(Jf2xKj), where ZA is the subelectrode resistance of reference electrode, Ujf2 is the voltage at output from j-th amplifier with frequency of f2, Jf2 is the voltage of narrow bandwidth current oscillator with frequency of f2.

EFFECT: wide range of functional applications.

15 cl, 10 dwg

FIELD: medical engineering.

SUBSTANCE: device has divider, comparison unit, oscillator, acoustic radiator, controllable current source, stable constant voltage source, perspiration equivalent unit, key member, illumination source, conductivity transducer having two electrodes, the first commutator, delay unit, trigger, inverter, discharge unit, the second commutator and feeding voltage availability indicator unit. The first delay unit inputs and the first commutator inputs are connected to comparison unit output. The first commutator input is connected to the first oscillator input which delay unit, trigger and inverter are connected in series. Inverter output is connected to the second input of the first and the second commutator. The first input of the second commutator is connected to the other conductivity transducer electrode and its output is connected to device body via resistor.

EFFECT: reduced current intensity passing through patient skin; excluded negative influence upon skin during prolonged operation time on patient arm during hypoglycemia attack; low power consumption.

2 cl, 4 dwg

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