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|Publication number
|Publication type
|Application number
|Publication date
|Nov 29, 2011
|Filing date
|Jul 11, 2007
|Priority date
|Jun 21, 2004
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|Scott Matthew Chetham
|Original Assignee
|Aorora Technologies Pty Ltd
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|Patent Citations (158), Non-Patent Citations (15), Referenced by (8), Classifications (16), Legal Events (8)
|External Links: USPTO, USPTO Assignment, Espacenet
This application is the continuation in part of U.S. patent application Ser. No. 11/629,804, filed Dec. 15, 2006, now abandoned, which is a National Stage of International Application No. PCT/AU05/000893, filed Jun. 21, 2005, which application claims priority to Australian Application No. 2004903334, filed Jun. 21, 2004 and Australian Application No. 2004906181, filed Oct. 26, 2004, All of these applications are herein incorporated by reference in their entirety.
The present invention relates to methods and apparatuses for monitoring biological parameters, and in particular to a method and apparatus for measuring cardiac function in a subject using bioelectric impedance or components of bioelectric impedance.
The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that the prior art forms part of the common general knowledge.
It is estimated that coronary heart disease will become the single biggest public health problem in the world by 2020, The treatment of coronary heart disease and other cardiovascular diseases therefore represents and increasingly large health and economic burden throughout the world in the coming years.
Cardiac output (CO), which can be defined as the amount of blood ejected by the ventricles of the heart per minute (measured in liters per minute), is governed by the metabolic demands of the body, and therefore reflect the status of the entire circulatory system. For this reason measurement of cardiac output is an essential aspect of haemodynamic monitoring of patients with heart disease or who are recovering from various forms of cardiovascular disease or other medical treatments.
One existing technique for determining cardiac function which has been developed is known as impedance cardiography (IC). Impedance cardiography involves measuring the electrical impedance of a subject's body using a series of electrodes placed on the skin surface. Changes in electrical impedance at the body's surface are used to determine changes in tissue volume that are associated with the cardiac cycle, and accordingly, measurements of cardiac output and other cardiac function.
A complication in impedance cardiography is that the baseline impedance of the thorax varies considerably between individuals, the quoted range for an adult is 20 Ω-48 Ω at a frequency between 50 kHz-100 kHz. The changes in impedance due to the cardiac cycle are a relatively small (0.5%) fraction of the baseline impedance, which leads to a very fragile signal with a low signal to noise ratio.
Accordingly, complex signal processing is required to ensure measurements can be interpreted.
An example of this is described in international patent publication no. WO2004/032738, In this example, the responsiveness of a patient to an applied current is modelled using the equivalent circuit shown in
Accordingly, the equivalent circuit includes an intracellular branch formed from a capacitance C representing the capacitance of the cell membranes in the intracellular pathway and the resistance R1 representing the resistance of the intracellular fluid. The circuit also includes an extracellular branch formed from resistance RE which represents the conductive pathway through the tissue.
WO2004/032738 operates based on the assumption that the cardiac cycle will only have an impact on the volume of extracellular fluid in the patient's thorax, and therefore that cardiac function can be derived by considering changes in the extracellular component of the impedance. This is achieved by applying an alternating current at a number of different frequencies. The impedance is measured at each of these frequencies and then extrapolated to determine the impedance at zero applied frequency, which therefore corresponds to the resistance RE. This is then determined to be solely due to the extracellular fluid component and hence can be used to determine attributes of cardiac function, such as stroke volume.
However, in practice the impedance at zero frequency would not be due solely to extracellular fluids but would be influenced by a number of other factors. In particular, cells do not act as a perfect capacitor and accordingly, the intracellular fluid will contribute to the impedance at a zero applied frequency.
A further issue in WO2004/032738 is that the process determines the impedance at zero applied frequency using the "Cole model". However, again this assumes idealised behaviour of the system, and consequently does not accurately model a subject's bioimpedance response. Consequently cardiac parameters determined using these techniques tend to be of only limited accuracy.
Described herein are methods and systems for determining one or more measures of cardiac function. In general, these methods may involve determining an actual characteristic frequency, measuring the instantaneous impedance or components of the impedance at that characteristic frequency, and using the instantaneous impedance (or a component of the impedance) value(s) to determine a measure of cardiac function. A characteristic frequency may be determined by analyzing the bioelectric response of the subject's body or tissue at various frequencies, as described in greater detail herein. An impedance (or a component of the impedance such as reactance, phase shift, magnitude, resistance) may be measured either directly or derived. A characteristic frequency may be determined for a particular subject either once, or periodically. For example, each measurement of instantaneous impedance may be made at a new characteristic frequency. This is described in greater detail below.
One variation of a method of determining a measure of cardiac function in a subject may include the steps of determining a characteristic frequency for the subject, determining the impedance or a component of the impedance at the characteristic frequency, and determining a measure of cardiac function using the impedance or a component of the impedance determined at the characteristic frequency.
In some variations, the characteristic frequency of the subject is determined by applying an electrical signal having a plurality of frequencies to the subject, determining an instantaneous impedance value at each of the plurality of frequencies, fitting the instantaneous impedance values to a frequency dependent function, and determining the characteristic frequency using the function. The characteristic frequency may be determined from an approximate maximum of the function. For example, the frequency dependent function may be a function based on a Wessel plot or a Cole plot, or a polynomial curve fit. The characteristic frequency may be determined over any appropriate frequency range. For example, the characteristic frequency may be determined by applying an electrical signal having a plurality of frequencies within the range of 2-10,000 kHz to the subject.
In some variations, the impedance (or a component of the impedance) at the characteristic frequency is determined by comparing an electrical signal applied to the subject (having a frequency at approximately the characteristic frequency) with an electrical signal received from the subject in response to the applied electrical signal. The component of impedance determined may be the reactance, the phase (e.g., phase shift) or the magnitude. For example, the reactance or the phase shift values measured at the characteristic frequency may be used to measure (or estimate) a characteristic cardiac function. In general, multiple ("instantaneous") values for the impedance or a component of the impedance may be determined during the course of a cardiac cycle.
Any appropriate measure of cardiac function may be determined using the characteristic frequency, including stroke volume and cardiac output. For example, stroke volume may be determined by multiplying the maximum change in impedance during a cardiac cycle by one or more constants including constants based on the subject's physical characteristics. As mentioned, the measure of cardiac function may be determined using the impedance (or a component of the impedance) at the characteristic frequency for a number of sequential time points. For example, instantaneous reactance values may be taken during an entire (or a portion of a) cardiac cycle. The same characteristic frequency may be used to determine the instantaneous impedance values used to determine the measure of cardiac function, or the characteristic frequency may be repeatedly determined for each time point or a subset of time points. For example, the measure of cardiac function may be determined by determining the characteristic frequency and the instantaneous reactance at the characteristic frequency for a number of sequential time points.
Also described herein are methods of determining a measure of cardiac output in a subject including the steps of applying an electrical signal having a plurality of frequencies to the subject, receiving an electrical signal from the subject in response to the applied signal, determining a characteristic frequency for the subject by comparing the applied and received electrical signals, determining at least one component of the impedance at the characteristic frequency, and determining a measure of cardiac function using the at least one component of the impedance determined at the characteristic frequency. As mentioned, the characteristic frequency may be determined by comparing the applied and received electrical signals to determine an instantaneous impedance value and fitting the instantaneous impedance values to a frequency dependent function. The at least one component of the impedance determined at the characteristic frequency may be the reactance, the phase (e.g., phase shift), the magnitude, or the resistance.
Any appropriate measure of cardiac function may be determined, including stroke volume and/or cardiac output. For example, indicia of cardiac function may be determined by first identifying the characteristic frequency, and then determining the instantaneous reactance values at the characteristic frequency for a number of sequential time points (e.g., during a full cardiac cycle). A measure of cardiac function may be determined by determining the instantaneous phase shift values at the characteristic frequency for a number of sequential time points during a cardiac cycle. As mentioned above, the measure of cardiac function may be determined by determining the characteristic frequency and at least one component of the impedance at the characteristic frequency for a number of sequential time points during a cardiac cycle.
Also described herein are systems for analyzing cardiac function in a subject. These systems may include a plurality of electrodes configured to be attached to a subject, and a processor connected to the plurality of electrodes. The processor may be configured to control the application of an electrical signal having a plurality of frequencies to the subject, receive an electrical signal from the subject in response to the applied signal, determine a characteristic frequency by comparing the applied and received electrical signals, determine at least one component of the impedance at the characteristic frequency, and determine a measure of cardiac function using the at least one component of the impedance determined at the characteristic frequency. In some variations, the system also includes a signal generator coupled to processor for generating the electrical signals applied to the subject. The systems may also include one or more sensors for detecting the electrical signals from the subject in response to the applied electrical signals.
In some variations, the system may also include processing logic for determining the measure of cardiac output by multiplying the at least one component of the impedance (e.g., reactance, phase shift) by one or more constants including constants based on the subject's physical characteristics. The processing logic may be implemented by software, hardware, or any combination of these. Thus, the processor may be a microprocessor configured to execute the processing logic.
Any of the systems described herein may also include one or more input devices in communication with the processor for entering at least some of the subject's physical characteristics. For example, the systems may include a keypad, mouse, memory, wireless connection or the like for receiving input. Physical characteristics may include height, gender, weight, pulse rate, age, ethnicity, etc.
An example of a process for determining parameters of cardiac function relating to a subject is described with reference to
In particular at step 100, alternating electrical signals are applied to the subject at a number of different frequencies fi, with electrical signals across the subject being detected at each of the respective fi, at step 110. The nature of the signals applied and detected will depend on the implementation as will be described below.
At step 120, at a first time instance tn the impedance Zi at each frequency fi is determined. At step 130, the impedance is used to determine an intracellular impedance parameter at the time tn. In one example, this is achieved utilising an appropriate model, such as a CPE (constant phase element) model, which will be described in more detail below.
This is performed for a number of sequential time instance tn, tn+1, tn+2 until it is determined that a complete cardiac cycle has been analyzed at step 140. This may be achieved by monitoring appropriate ECG signals, or alternatively simply by processing sufficient time instances to ensure that a cardiac cycle has been detected.
At step 150, the intracellular impedance parameter, and in one example, changes in the intracellular impedance parameter, is used to determine cardiac parameters.
This technique takes into account that the impedance fluctuation of the thorax during the cardiac cycle is dependent on both changes in blood volume and changes in the impedance in the blood itself.
Blood is a suspension of erythrocytes, with a high resistivity, and other cells in a conducting fluid called plasma. The erythrocytes of stationary blood are randomly oriented as shown in
The anisotropy of the resistivity is due to the longer effective path length for the current travelling normal to the axis of the vessel compared with the current flowing parallel to the vessel. As a result, the resistance of the intracellular fluid alters depending on the orientation of the erythrocytes, and hence depends on the flow of blood.
Furthermore, the extent of the anisotropy is shear-rate dependent since the orientation of the erythrocytes is influenced by the viscous forces in flowing blood. As a result, the resistivity is in turn also dependent on the flow rate.
It is therefore possible to take this into account by determining cardiac function on the basis of intracellular parameters, as opposed to using extracellular impedance parameters as in the prior art. This can therefore be achieved using the equivalent circuit shown in
Thus, in this instance, the impedance measurements can be used to determine values for the intracellular resistance RT and the capacitance C, for example, by determining values of R0 and Rω, and then using these to solve the Cole equation using appropriate mathematical techniques.
In this instance however, modelling the resistivity as a constant value does not accurately reflect the impedance response of a subject, and in particular does not accurately model the change in orientation of the erythrocytes, or other relaxation effects.
To more successfully model the electrical conductivity of blood, an improved CPE based model can be used as will now be described with respect to
In this example, to accurately determine the characteristic impedance, and interpret the contribution of cardiac effects to the impedance, an equivalent circuit based on a free conductance parallel model is used, as shown in
In this example, the circuit includes an extracellular conductance G0 that represents the conductance of electrical current through the extracellular fluid. The intracellular conduction path includes a constant phase element (CPE) represented as the series connection of a frequency dependent conductance, and a frequency dependent capacitance.
The two equations below define a general CPE:
Y CPE=(ωτ)m(G mτ=1 +jB ωτ=1) (1)
In this equation τ represents a frequency scale factor and, ωτ is dimensionless.
The parameter m defines the extent of the frequency dependence of the admittance of the CPE YCPE and the frequency scale factor with τ. It is known that for biological tissue m is in the range of 0≦m≦1.
In one example, the CPE is in accordance with Fricke's law (CPEF) although other forms of CPE could be used. It is usual practice to use the exponent symbol α (m=α) for Fricke CPE's.
In order to make the model compatible with relaxation theory, the series ideal resistor is changed to a free resistor parameter Rvar so that the characteristic time constant τr will be a dependent parameter.
The result is that the conductance of the circuit can be expressed as follows:
Here τYm is a new characteristic time constant. The subscript m is used to identify the new variable from the previous variables and is consistent with the nomenclature know to those skilled in the art.
By putting a nominal fixed value to the time constant τy it is possible to follow the CPE by calculating the R1 using the equation.
In this instance, the variable resistance parameter Rvar is dependent on the orientation of the erythrocytes and as a result, changes in Rvar can be used to determine the rate of flow of blood within a subject. Consequently, it is possible to determine information regarding cardiac output, or the like.
An example of apparatus suitable for performing an analysis of a subject's bioelectric impedance to determine cardiac function will now be described with reference to
As shown the apparatus includes a processing system 10 having a processor 20, a memory 21, an input/output (I/O) device 22 and an interface 23 coupled together via a bus 24. The processing system is coupled to a signal generator 11 and a sensor 12 as shown. In use the signal generator 11 and the sensor 12 are coupled to respective electrodes 13, 14, 15, 16, as shown.
In use, the processing system 10 is adapted to generate control signals, which causes the signal generator 11 to generate an alternating signal which is applied to a subject 17, via the electrodes 13, 14. The sensor 12 then determines the voltage or current across the subject 17 and transfers appropriate signals to the processing system 10.
Accordingly, it will be appreciated that the processing system 10 may be any form of processing system which is suitable for generating appropriate control signals and interpreting voltage data to thereby determine the subject's bioelectrical impedance, and optionally determine the cardiac parameters.
The processing system 10 may therefore be a suitably programmed computer system, such as a laptop, desktop, PDA, smart phone or the like. Alternatively the processing system 10 may be formed from a specialised hardware. Similarly, the I/O device may be of any suitable form such as a touch screen, a keypad and display, or the like.
It will be appreciated that the processing system 10, the signal generator 11 and the sensor 12 may be integrated into a common housing and therefore form an integrated device. Alternatively, the processing system 10 may be connected to the signal generator 11 and the sensor 12 via wired or wireless connections. This allows the processing system 10 to be provided remotely to the signal generator 11 and the sensor 12. Thus, the signal generator 11 and the sensor 12 may be provided in a unit near, or worn by the subject 17, whilst the processing system is situated remotely to the subject 17.
In practice, the outer pair of electrodes 13, 14 are placed on the thoracic and neck region of the subject and an alternating signal is applied at a plurality of frequencies either simultaneously or in sequence, (two are sufficient but at least three are preferred with five or more being particularly advantageous) in the range 2-10,000 kHz. However the applied waveform may contain more frequency components outside of this range.
In the preferred implementation the applied signal is a frequency rich voltage from a voltage source clamped so it does not exceed the maximum allowable patient auxiliary current. The signal can either be constant current, impulse function or a constant voltage signal where the current is measured so it does not exceed the maximum allowable patient auxiliary current.
A potential difference and/or current are measured between an inner pair of electrodes 16, 17. The acquired signal and the measured signal will be the superposition of signals at each of the applied frequencies and the potentials generated by the human body, such as the ECG.
Optionally the distance between the inner pair of electrodes may be measured and recorded. Similarly, other parameters relating to the subject may be recorded, such as the height, weight, age, sex, health status, and other information, such as current medication, may also be recorded.
The acquired signal is demodulated to obtain the impedance of the system at the applied frequencies. One suitable method for demodulation is to use a Fast Fourier Transform (FFT) algorithm to transform the time domain data to the frequency domain. Another technique not requiring windowing of the measured signal is a sliding window FFT. Other suitable digital and analog demodulation techniques will be known to persons skilled in the field.
Impedance or admittance measurements are determined from the signals at each frequency by comparing the recorded voltage and current signal. The demodulation algorithm will produce an amplitude and phase signal at each frequency.
An example of the process of measuring a subject's bioelectric impedance and then interpreting this will be described in more detail with reference to
At step 200 the processing system 10 generates predetermined control signals causing the signal generator 11 to apply current signals to the subject 17 at a number of frequencies fi, over a time period T. The current signals applied to the subject 17 may be provided at the frequencies fi sequentially, or simultaneously, by superposing a number of signals at each corresponding frequency fi.
It will be appreciated that the control signals are typically generated in accordance with data stored in the memory 21 and this can allow a number of different current sequences to be used, with selection being made via the I/O device 22, or via another appropriate mechanism.
At step 210 the sensor 12 measures the voltage across the subject 17. In this regard, the voltage signals will typically be analogue signals and the sensor 12 will operate to digitise these, using an analogue to digital converter (not shown).
At step 220 the processing system 10 samples the signals from the signal generator 11 and the sensor 12, to thereby determine the current and voltage across the subject 17.
At step 230, a filter is optionally applied to the voltage signals at step 230 to remove respiratory effects, which typically have a very low frequency component in line with the patient's rate of breathing. It will be appreciated that filtering may be achieved by the sensor 12 or the processing system 10, depending on the implementation.
At step 240 ECG vectors are optionally extracted from the voltage signals. This can be achieved as the ECG signals typically have a frequency in the region 0 Hz to 100 Hz, whereas the impedance signals are in the region of 5 kHz to 1 MHz. Accordingly, the ECG signals may be extracted by any suitable technique, such as demodulation, filtering or the like.
At step 250 the signals may also undergo additional processing. This can be performed, for example, by further filtering the signals to ensure that only signals at the applied frequencies fi, are used in impedance determination. This helps reduce the effects of noise, as well as reducing the amount of processing required.
At step 260, the current and voltage signals sampled at time tn to determine the impedance Zi at each frequency fi.
At step 270 a function is fitted to the impedance values.
An example of this is shown in
Alternatively a Wessel plot may be used as shown in
In practice noise elimination may be necessary to accurately fit a function to the data. In one example, elimination of noise at certain frequencies can be performed by initially fitting a function to the measured data and then systematically removing outlier points from the data set and re-fitting the function to the reduced data set.
Accordingly, at step 280 the processing system 10 operates to determine if there are outlier points, which are considered to be points that are greater than a predetermined distance from the determined function.
It will be appreciated that the function used, and the determination of outlier points may be achieved utilising standard mathematical techniques.
If it is determined that there are outlier points, these are removed from the data set and a new function fitted to the remaining values at step 290. At step 290 the processing system 10 determines if the fit is improved and if so the outlier point is excluded from the data set permanently with the new function being assessed at step 310. This is repeated until all outliers that affect the data are removed.
If it is determined that the fit is not improved at step 300 the outlier is retained and the previous function used at step 320.
If there are no outliers, or once outliers have been excluded from the data set, the plot is then used to determine values from Ro and R∝ using the determined function.
In one example, the function is used to calculate R0 and R∝. Alternatively, this can be used to determine the impedance at the characteristic frequency. As is apparent to one of skill in the art, the characteristic frequency is apparent from this procedure (e.g., the maximum reactance in the frequency range).
For example, in the case of the function shown in
In this approach the function is analysed to find the frequency where impedance (Z) changes (ΔZ) by less than 1% with a frequency increase of 25 kHz. The resistance or impedance Z measured at this frequency is identified as R∝ and represents resistance of the circuit if an infinitely high frequency was applied. Other methods of determining this pseudo-plateau region may be known to those skilled in the art.
Similarly, the impedance at zero applied frequency R0 can be determined as the value at which the function would intercept the y-axis.
If a "Wessel" plot type function is used, as shown in
Additionally α can be determined from the angle subtended by the arcuate locus from R0 to R∝. By comparing this to m determined from susceptance data, this allows whether the Fricke criteria for relaxation phenomena of biological materials is met. In the event that they are equal or within a predetermined range of each other, then the Wessel diagram method may be applied with reasonable accuracy. In the event that m and α are not sufficiently close in value then the function fitting approach described above is a more appropriate method for determining the quantities of interest for the free conductance model.
At step 340 the processing system 10 uses the values of either R0 to R∝, or the characteristic impedance, together with equation (5) to determine the intracellular impedance parameter, which in this example is the intracellular variable resistance parameter Rvar.
As an alternative to determining values of R0, R∝, or the characteristic impedance Zo, the equation (5) can alternatively be solved mathematically, for example by using a number of different impedance values at different frequencies fi to solve a number of simultaneous equations. These values can be based on directly measured values, although preferably these are values determined from the fitted function, to thereby take into account the impedance response across the range of applied frequencies fi.
At step 350 it is determined if a full cardiac cycle has been completed and if not the process returns to step 240 to analyse the next time instance tn+1.
At step 360, once a full cardiac cycle has been completed, the processing system 10 operates to determine the change in the intracellular resistance parameter Rvar over the cardiac cycle before using this to determine cardiac parameters at step 370.
A typical plot of the time varying impedance obtained by the present method is shown in
The centre graph of
As will be appreciated by those skilled in the art additional measurements can also be incorporated into the present method or conducted simultaneously. For example, the inner electrodes can also be used to record ECG vectors. In order to generate more ECG vectors more inner electrode combinations are required. The outer electrodes can also be used to record the ECG vectors. The processing unit, or the operator, can automatically or manually select the most appropriate ECG vector. An external ECG monitor can also be connected or alternatively a separate module can be incorporated into the invention with additional electrodes to calculate the ECG vectors.
The ECG can advantageously be used to aid in the determination of cardiac events. An example ECG output is depicted in the lower graph of
To calculate certain cardiac parameters from the impedance waveform, fiducial points must also be suitably identified. The ECG data and/or other suitable physiological measurement techniques may be employed to aid this process.
Other physiological parameters that could be used to assist in identifying fiducial points in the cardiac cycle include invasive/non-invasive blood pressure, pulse oximetry, peripheral bioimpedance measurements, ultrasound techniques and infrared/radio frequency spectroscopy. Such techniques can be used singularly or in a plurality to optimally determine cardiac event timing.
In one example an artificial neural network or weighted averages to determine the cardiac events as identified by conductance measurements combined with other methods of physiological measures offer an improved method of identifying these points. In the present example the start and end of left ventricular ejection are indicated by the vertical lines on the graphs of
These fiducial points can be used to obtain impedance values of interest. For example, the maximum rate of change in the intracellular resistance value Rvar over left ventricle ejection which is indicated on the central graph of
Measures of cardiac function can then be determined from this data. For example, the following method can be used to calculate blood velocity and stroke volume. The present example uses impedance measures to calculate cardiac output. However the same functions can be described using admittance or a combination of the two. The following formula can be used to calculate cardiac output:
The person skilled in the art will be able to determine appropriate values for these constants dependent upon the patient and situation in which the method is applied.
Whilst the example described above has been described in the context of providing determining cardiac output of the heart, embodiments of the present invention can be applied to determine other measures of cardiac performance, including but not limited to, stroke volume, cardiac index, stroke index, systemic vascular resistance/index, acceleration, acceleration index, velocity, velocity index, thoracic fluid content, left ventricular ejection time, Pre-ejection period, systolic time ratio, left cardiac work/index, heart rate and mean arterial pressure.
As described briefly above, measures of cardiac performance and function may also be determined using the characteristic frequency. Thus, the characteristic frequency may be determined during a cardiac cycle by applying an electrical signal having a plurality of frequencies (or multiple electrical signals at different frequencies), detecting electrical signals in response to the applied signals, processing the detected signals (e.g., to remove unwanted components such as ECGs and other signals), comparing the applied electrical signals at each frequency with the response signals at each frequency, and fitting the signals to a function from which the characteristic frequency may be determined. As previously described,
The signal(s) applied to the subject may be a signal (or signals) having a plurality of frequency components, or a series of signals at different frequencies. The response signal that is measured from the subject after the application of one or more electrical signals arises because of the electrical properties of the body. This response is usually referred to as a response signal. The response signal may also be referred to as an evoked response or evoked signal, and is typically a passive response. For example, the response does not usually include a regenerative evoked (e.g., active) response from electrically active tissue.
Once the characteristic frequency has been determined, this characteristic frequency may provide a relatively accurate means of determining cardiac function by then applying an electrical signal at the characteristic frequency and receiving the response electrical signal at that frequency. This electrical stimulation and sampling may be repeated during a complete or partial cardiac cycle. For each time point, the stimulated and response signals may be compared (e.g., after filtering or other signal processing) to determine an instantaneous impedance or any components of the instantaneous impedance, such as resistance, reactance, phase and magnitude. As is known in the art, the resistance and reactance, and the impedance and phase are all mathematically related, and with any two you can calculate the other two. Further, as is known in the art, any of these components can be determined from the applied and response signals.
For example, in
Next, the impedance, or a component of the impedance, can be determined at different time points during all or part of a cardiac cycle 1003. As described above, the intracellular resistance may be calculated from the impedance. In some variations the reactance component of the impedance is determined at different time points of a cardiac cycle by applying electrical signals at the characteristic frequency. Thus, at least one reactance time point may be determined at that characteristic frequency. This reactance time point may be referred to as an instantaneous reactance at that time point. In some variations the component of the impedance determined at each time point using the characteristic frequency is phase, magnitude (or both). In some variations the instantaneous impedance is determined using the characteristic frequency at each time point.
As mentioned above, a new characteristic frequency may be determined during the cardiac cycle, as indicated by the dashed line 1011 in
Finally, a measure of cardiac function may be determined using the instantaneous impedance (or a component of impedance) value(s) determined at the characteristic frequency 1007 in the previous steps. For example, the instantaneous impedance values measured at the characteristic frequency may be used to determine a stroke volume and/or cardiac output. The maximum change in impedance, (dz/dt)max, is proportional to the stroke volume and also to the cardiac output. For example, stroke volume may be represented as:
where: SV=stroke volume, (dz/dt)max=maximum rate of change in measured impedance at the beginning of systolic cycle, VET=left ventricular ejection time, and L′=thoracic length estimated from the subject's height and weight using a nomogram. L′ also accounts for blood resistivity. ZB is a baseline impedance value. Thus, the constants may be combined, expressing the stroke volume in terms of elements (e.g., (dz/dt)max) that may be determined for each cardiac cycle. Cardiac output is related to stroke volume (e.g., cardiac output=SV*heart rate).
In one example, the instantaneous reactance at the characteristic frequency may be used to determine a measure of cardiac function. For example, the instantaneous reactance at the characteristic frequency can be measured at each sample point during a cardiac cycle by stimulating the subject at the characteristic frequency. The change in the reactance (dX/dt)max is also proportional to the stroke volume and the cardiac output, and may therefore be used (in conjunction with appropriate monograms) to determine these measures of cardiac function.
A system for analyzing cardiac function in a subject may include any of the elements described above, and may also include one or more processors for executing the procedures described herein. For example, a system may include a processor (e.g., microprocessor) for controlling the application of an electrical signal having a plurality of frequencies to the subject 1101. Thus, the processor may be connected to a signal generator and electrodes to be connected to the subject for stimulation. The controller may also be connected to electrodes for receiving an electrical signal from the subject in response to the applied signal 1103. The input signal may also be sent to the controller, and both the input and output signals may be digitized, filtered, or otherwise conditioned. The processor may further determine a characteristic frequency by comparing the applied and received electrical signals 1105, as described above.
The characteristic frequency may then be used to determine an instantaneous reactance, or any other appropriate characteristic of impedance, including phase 1107. For example, the system may detect the relative phase shift (dφ/dt) between the injected signal and the response signal at discrete times during a full cardiac cycle or a portion of a cardiac cycle by applying an electrical signal at the determined characteristic frequency and comparing the phase of the response signal to the applied signal. As mentioned above, in some variations, the characteristic frequency may be determined once during the cardiac cycle (e.g., at the start of the measurement), or a new characteristic frequency may be determined before determining the component of the impedance (e.g., reactance or phase shift) at each time point, as indicated by the dashed line 1117 in
These instantaneous impedance values determined at the characteristic frequency (e.g., the instantaneous impedance, instantaneous reactance, instantaneous phase shift, etc.) may be stored by the system. For example, the processor may include a memory to store these values. In some variations all of the values are not stored, but only a running value (e.g., the maximum value, a sum of the values, a product of the values, etc.) is stored. These stored values may be used to determine a measure of cardiac function 1111. For example, the phase shift (dφ/dt) values may be used to determine stroke volume and/or cardiac output. For example, the phase shift may be proportional to the changes in blood flow in the aorta, as previously described. Thus, the stroke volume may be expressed as:
where VET is ventricular ejection time, and C′ is a constant that may be based on individual patient characteristics (including height, weight, gender, age, etc.). As previously described, the VET may be determined for each cardiac cycle. For example, the ECG may be used to determine the length of each heart beat, as well as the start of ejection and the end of ejection, from which VET can be estimated. Heart rate (and therefore cardiac output) may also be determined from the phase information.
The measure of cardiac function determined may be displayed, stored or transmitted. Thus, any of the systems for analyzing cardiac function described herein may include a display (e.g., screen, printer, etc.) or telemetry (wireless, LAN, etc.), or the like. The systems described herein may also include one or more inputs such as keyboards, mouse, touch screen, etc. for inputting subject information.
Persons skilled in the art will appreciate that numerous variations and modifications will become apparent. All such variations and modifications which become apparent to persons skilled in the art, should be considered to fall within the spirit and scope that the invention broadly appearing before described.
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|U.S. Classification
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|International Classification
|Cooperative Classification
|European Classification
|Sep 26, 2007
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text:
AHRQ Launches Follow-Up Series of Reports on "Closing the Quality Gap"
The report is based on research by the RAND Evidence-based Practice Center under contract to AHRQ. The new series will include eight reports and is a follow-up to the series "Closing the Quality Gap: A Critical Analysis of Quality Improvement Strategies," which AHRQ launched in 2004.
The new series of reports "broadens the scope of settings, interventions, and clinical conditions, while continuing the focus on improving the quality of health care through critical assessment of relevant evidence," according to the summary report.
The summary describes the scope and key messages of the eight reports. The topics the reports will discuss include the following:
• Effectiveness of bundled payment programs
• Effectiveness of the patient-centered medical home
• Quality improvement strategies to address health disparities
• Effectiveness of medication adherence interventions
• Effectiveness of public reporting
• Prevention of healthcare-associated infections
• QI measurement of outcomes for people with disabilities
• Healthcare and palliative care for patients with advanced and serious illness
More Articles on AHRQ:Neonatal ICU CLABSI Rates Drop by 58% in Less Than a Year, AHRQ Reports
AHRQ-Funded Initiative Decreased Hospitals' CLABSI Rate 41%
Patient Safety Tool: Primary Care TeamSTEPPS Training Materials From AHRQ
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subset: commoncrawl


text:
Issues of concern to people who live in the west: property rights, water rights, endangered species, livestock grazing, energy production, wilderness and western agriculture. Plus a few items on western history, western literature and the sport of rodeo... Frank DuBois served as the NM Secretary of Agriculture from 1988 to 2003. DuBois is a former legislative assistant to a U.S. Senator, a Deputy Assistant Secretary of Interior, and is the founder of the DuBois Rodeo Scholarship.
Wednesday, January 26, 2011
Norwegian Boy Fends Off Wolf Pack with Heavy Metal
While walking home from the busstop this week, a 13-year-old Norwegian school boy stumbled upon four wolves. In the end, it may have been his love of heavy-metal music by the band Creed that saved his life. Walter Eikrem listened to music on his mobile phone as he often does as he made his way home from school in the southern Norwegian town of Rakkestad earlier this week. The path leading from the stop where he catches the school bus to his family's farmhouse traverses a gently sloping hillside. All of a sudden, he made out something gray on the hillside. "At first, I thought it might have been the neighbor's dogs," he later told TV2, Norway's largest commercial broadcaster. What he actually encountered, though, were four wolves. "I was afraid they would attack me," Walter told the Norwegian tabloid VG, describing the incident, which took place on Monday. But he didn't let his fear show. Remembering his parents' advice, Walter pulled the earphones out of his mobile phone, turned the volume all the way up and blasted heavy metal music over its miniature speakers. At the same time, he yelled as loud as he could while flailing his arms about wildly to scare off the pack of wild animals...more
Posted by Frank DuBois at 6:34 AM
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text:
Story highlights
Vitiligo is a condition that affects all races, but is more noticeable in people with darker skin.
She's been labelled as the next big thing in fashion.
The model has apparently caught Lewis Hamilton's eye, and with striking looks like hers; courtesy of vitiligo, it's easy to see why the racing driver has reportedly taken a liking to Winnie Harlow.
READ: Despite Vitiligo, Chantelle Winnie is the cover girl of latest issue of Nord Magazine
Winnie was a little girl nicknamed Zebra because of the white patches caused by her skin condition. However, she made her way to become a top model.
Winnie, who grew up with Michael Jackson's skin condition, has been tipped to be fashion's next big thing
As a baby, Winnie was diagnosed with vitiligo around the age of four, making her among one per cent of the population who has the condition
Despite the skin disorder, you won't deny just how incredibly hot she is!
Winnie reveals that she was physically taunted about her skin and a group of girls 'jumped her' in a fight, which led to her being suspended because she started skipping class
She said she dropped out of school at the age of 17 and never looked back
In an interview Cosmopolitan magazine, she said, 'Kids called me a cow and mooed at me. I remember sitting by my window wishing upon the stars that my skin condition would go away.'
Guess the stars gave her something even better!
If that isn't enough, she's pals with Mariah Carey's ex, Nick Cannon, parties with Drake, and was snapped up to star in Beyonce's Lemonade music video
Although just 17 then, she eloquently told viewers, 'People have black skin, people have brown skin, I have both.'
'When I got older, it got harder because when kids get older they get meaner, so I went through a lot of bullying and people calling me like zebra or cow so it was really hard growing up.'
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text: I received my invoice for my dip and ship and tanning for some backskins. I went to the bank a tried to do a wire transfer and the Namibia infor on this end did'nt match swift code ect. They said they could send it blindly but I would have to pay the same fee to get it back if it did not go through. The bank recommended I contact the taxidermist and make sure his infor was correct. Just asking if this is a common occurence between american and namibian banks


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It must sting to be The Fancy, a $10 million website about collecting pictures of stuff you want to buy. They launched in 2010, with celebrity endorsements and exclusive invite-only access, and all the trimmings of startup success–and then Pinterest happened, basically making a national phenomenon out of more-or-less the exact same concept.
So The Fancy is taking it to the wall on 2nd and A, hiring Tats Cru to paint a big Pinterest logo and then buffing over it with "FANCY" all at once. It's definitely a marketing play that is cognizant of street culture, but even ignoring its perhaps too-self-awareness, how many people are going to look at this and realize it's an ad for The Fancy at all when it simply looks like a Pinterest ad that got buffed? (Maybe there's a "dot com" behind that Honda.) (Thanks, Jay, for the shot!)


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|1,615 sq. ft.
|Property type
|Minimum Stay
|2 nights
Find your own secluded oasis at this Borrego Springs hideaway! Tucked in a gated community surrounded by natural beauty and sunshine, this 2-bedroom, 2 bathroom home is made for relaxation and leisure. Featuring enough space to sleep up to 4 guests, your whole party will fall in love with this desert gem!
Located in a quiet and secure gated community, you're sure to be impressed with the lush landscaping and mountainous backdrop. When you arrive after a long day of traveling, mix up your favorite drink at the bar and challenge your companions to a game of pool or enjoy a DVD together on the flat screen TV in the inviting living room. A large wood fireplace makes the space feel warm and grand. When your stomach lets you know it's time for dinner, head to the fully equipped kitchen and prepare one of your favorite meals. Savor your masterpiece at the charming dining table or take it outdoors and dine al fresco as you gaze out at the striking mountain and golf course views. When the sun starts to sink below the horizon, retreat to one of the comfortable bedrooms for a night of serenity and uninterrupted sleep. The private location of this home makes it ideal for those seeking peace and quiet.
One of the best features of this home is the fantastic community in which it's situated! When the day heats up, cool off in one of the community pools or swim laps in the Olympic-sized lap pool. If you're in the mood for some barbecue, head to the community gas grills and cook up a juicy burger. Golfers will certainly want to bring their clubs along, as the home backs up to Ram Hill Golf Club. Set an early morning tee time and simply walk from the property to the green. Non-golfers will be able to watch from the comfort of the home's private back patio!
When you're not taking advantage of the fantastic community amenities, you can head out into the fantastic town of Borrego Springs. Surrounded by 600,000 acre Anza-Borrego Desert State Park, Borrego Springs is a California town unlike any other. Locals are laid back and the living is easy, as the town is free of stop lights and chain stores. Take advantage of pleasant weather and vast hiking and biking trails. Explore the unique shops and restaurants in town, or practice your swing on the links of multiple local golf courses. However you decide to spend your time in Borrego Springs, you'll love the backdrop of awe-inspiring beauty that surrounds you at this California dreamland.
Evolve Vacation Rental Network is on a mission to make vacation rental easy for guests. Every property in our network has been vetted and verified so you can book with confidence. If you have questions prior to your trip, we are happy to assist you 7 days a week. During your stay, your designated Guest Contact will be available 24/7 to help with any issues that may arise.
Key Residence Features:
- Amenities include a fully equipped kitchen, pool table, fireplace, private patio overlooking the mountains, bar area, and much more!
- Access to community amenities including pools, hot tubs, and barbeque grills
- Stunning and private location in a gated community on a golf course
Bedroom Configuration:
- Master Bedroom: King-sized Bed
- Bedroom 2: Queen-sized Bed
- No smoking
- No pets allowed
- Must be 25 years or older to book
- Additional fees and taxes may app
This HomeAway partner has demonstrated and is committed to fast response times, the best rates, and a great traveler experience.
This property was everything I had hoped for, and more. Spacious, airy, clean and bright. Amazing views of the golf course and mountains beyond. Super comfortable beds and soft great linens. (I actually looked for the tag so I could buy the same brand!) We will return soon and next time for longer than three days. Thank you for sharing your great home!
This is a lovely property, with stunning views over the landscaped back yard and the golf course to Fonts Point, the Santa Rosa Mts. and Fonts Point. The beds are comfortable and the entire house is immaculately clean. The kitchen is decently equipped. Having the community pools and Jacuzzi a short walk up the street is a real bonus. Community grills in the same complex are kept very clean - which is not always the course. You can walk the paths through the golf course (or just stay on the roads - almost no traffic) with extraordinary views all around the northern end of Anza-Borrego State Park. The entire complex is beautifully landscaped. We also had a great time with the pool table.
Property was exactly what we wanted; two large bedrooms, nice kitchen and living space, right up against the Ram's Hill golf course. Lovely view of the course right out the back patio. Close to the community pool and bbq. Check-in was quick and easy at the entry gate to the Ram's Hill development. Monique was able to arrange for an early check-in. Had a wonderful time. Would highly recommend property.
This is an excellent home away from home for a small family! My 2 grandsons loved the pool table. The home is spacious. Even laundry soap was provided for the washer and dryer. Very nice!
My family of 5 stayed here for Thanksgiving weekend and had a perfectly relaxing, serene, and fun time. The location and views are spectacular! We had everything we needed to cook almost every meal and enjoyed sitting on the patio any time of day and night. I have to say, at first we missed having wifi but soon realized we didn't miss it at all! The pool table was our best entertainment! Loved it! Wanna go back!
A very comfortable, spacious house, with gorgeous views of the mountains; it's an excellent value for Borrego Springs. The house was very clean and had all we needed for a relaxing, quiet stay. Perfect location for driving to nearby hiking trails in the park. Being just steps from the wonderful neighborhood pool made it even better. The owner kindly allowed us to check in early and leave late as there were no other guests departing or arriving immediately before or after our visit. We greatly appreciated that, and we look forward to returning.


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" Earn cash back on your online purchases from over 400 UK retailers. It's free to join and you even get £3.50 free when you register. "
i joined my shopping rewards about 2 months ago and it is free to join and you get 3.50 for joining
i found the site to be quite good and while it is really easy to move round the site from page to page and find what your looking for it does take a while to process your money,
once your account has reached £20 they will automatically send you a cheque for the amount earned,i have earned £40 but i am still waiting for confirmed status to go onto my account before i can recieve any earned money,i have actually been waiting for about 3-4 months.
i keep checking but have not had any change to my account so stopped shopping to wait and see if anything happens first.
im sure the money will come in the end as it has a lot of members but just a bit of a pain to wait,may be different for you!
I first came across this website by chance when i typed in cashback into googles search engine
*Signing up*
Pretty standard form in my opinion . It asks for information like date of birth,name,email adress etc. They give you £3.50 for signing up and if you get someone to refer you they get a fiver once you have earned your first £20.
*The website*
Easy to navigate,everythings stated clearly
* Shops and Businesses *
There are loads of shops on this from avon to forbidden planet.
* Problems *
i had no problems with this website until i got near the pay mark-now things are not tracking as well as they used to. Once i get to the £20 i am going to stop using this site
*Daily clicks*
Like other cashback sites this one also offers daily cashback on kelko and the high street web. One thing i dont like about them is that they only allow 1000 per month for their entire member base.If other sites can do it all month why cant they?
I first heard about myshoppingrewards (MSR) from my sister. I thought it sounded good so I signed up under her referral link. I first joined in 2006 and I still log into my account regularly.
~ The Website ~
The website is easy to navigate with coloured tool bars which make it look eye catching. When you go to the website the main part of the page is asking you join. This is an attractive design and tells you that if you sign up you will get a £3.50 sign up bonus. Signing up is simple, and you have to provide the usual details (name, date of birth, email, home address - so they can send the cheque, etc)
Once you are signed up you are ready to begin. Once logged into your account, there is a purple box on the right hand side of the page with the account information. This tells you your current balance, and there are links to pages where you can update your details, refer friends or alter newsletter settings etc.
The toolbar across the top of the page is green and allows you to access your favourites, vouchers, competitions, easy cash, free stuff and help. These are easy to use and make the site easy to navigate. I didn't use the favourites at first, but now that I do more online shopping I have added the shops that I use most often and this makes logging into MSR quicker and more convenient before doing the shopping that you would usually do.
~ Shops and Businesses ~
There is a large list of categories in a yellow tool bar on the left side of the page. The top link is 'All shops' so you can search for the shop you are looking for or browse through the categories.
There are a huge number of shops listed on MSR and I always make a point of going through here whenever I shop online to see if cashback is offered.
Each website offers a different amount of cashback ranging from 0.1% - 10% or a set value. There are many major retailers as well as ones I haven't heard of previously.
I use a number of different websites regularly including Avon (4% cashback), The Book People (2.5%) and ebay (15% of fees cashback). I have also used a number of other websites on various occasions including Blackwell Books, Waterstones, Hawkins Bazaar and play.com.
My car insurance was due for renewal in December so I decided to look on here. I found a quote I was happy with from More Than and I placed my order and got £22.50 cashback. This was the cheapest quote I could find as I had only been driving for 1 year, so not only was the insurance cheaper, I got cashback too!
~ Problems ~
I have not had many problems with cashback not appearing in my account but when I bought a book from Blackwell's, the cashback offered was 5% and it did not appear in my account. You have to wait at least 2 weeks before you can submit a 'ticket' about missing cashback. I did this and had to fill in the details of the order (order number, shop, order amount, date etc) and a couple of weeks later I got my cashback. The website states that they will look into any cashback not received but they cannot guarantee that the retailer will pay out. This is the only problem I had and it was sorted out quite quickly so it won't stop me placing future orders.
~ Easy Cashback ~
There are also daily clicks with websites such as the high street web, kelkoo and buy central. These offer between 1p and 5p for searching through them and if you do this every day it soon adds up. I don't do a large amount of online shopping but I log into MSR most days and this adds up and keeps my account balance increasing.
You can also sign up to survey sites or newsletters etc for set amounts, which also boosts the account balance nicely.
~ Payment ~
The cashback usually appears into your account the next day but it appears as 'pending' but doesn't appear as confirmed for a couple of months. Once the confirmed balance has reached £20 you automatically get sent a cheque on the next payment day (once a month). By the time my money has become confirmed I usually have about £26 and I have had 3 payments meaning that I've earned £81.65 in total in the two years I've been using it. I also have £14 in my account. This may not sound like a lot for the length of time but it is money I would not have had and I would have done the same online shopping anyway.
The website notifies the members when the payment has been sent out and the three payments I've had have come a few days later.
~ Referring Friends ~
If you refer a friend you can earn £5 when they reach a confirmed balance of £20. I have referred a few people but no one has reached the £20 yet so I have not received the bonus. However, when I reached my first £20 my sister received the (then £8) referral bonus without any problems.
~ Advantages ~
· Lots of shops
· Good cashback amounts
· Once payment is sent it arrives quickly
~ Disadvantages ~
· Takes a while for pending money to become confirmed
~ Overall ~
I would recommend this website even if you don't do a huge amount of online shopping as you might as well have the cashback from the small amount you do. You can also boost your earnings with the daily clicks and sign ups and even if it takes a while it will all add up. I really like this site and although I've joined other cashback sites I always come back to this one, as I feel loyal to it. If you are interested in joining let me know and I'll send you my referral link.
Thanks for reading!
MyShoppingRewards.com is another one of those cashback sites which instead of giving cashback to its members, tends to waste their time and pay them nothing. In fact it should be renamed MyShoppingPunishment.com. I've never been that active on this site because other similar sites such as Rpoints and Greasy Palm have always had better offers or better deals and you tend to know where you are regarding payments. Nevertheless over time I have accumulated some cashback.
The system works like this:
When you receive cashback for an item it immediately goes into a pending category and stays there for a couple of months or so before it is transferred and added to your true total. This is the amount you can withdraw once it has reached a total of more than £20.
When you reach this amount you will receive a cheque automatically for exactly £20. So say you reach £24, you will be left with £4 left in your account which you won't be able to get your hands on until you pass the £20 barrier once more. However, once you reach £20 or more you have to wait a further 2 months before your cheque is sent. In other words, MyShoppingRewards seems to use every trick in the book to delay or stop its members from getting their payment.
My Experience:
I have been a member for... it must be about 12 months and I reached a cashback total of just over £20 about two months ago. I was due for a pay out on the first of August. Well that's what I thought. I had already heard a few negative stories about this site - about cashback not being paid or money going missing, so I made sure to log in and check my account on a regular basis. Last week I had a surprise. My total is now only £18. None of my cashbacks have been reversed but obviously some have been removed from my account without explanation - just enough so that I am below £20. I have sent emails asking for an explanation but as you might guess they received no response. Even if I make up the total again with £2 worth of cashback, this now means that I will now have to wait at least a further 4 months in order to get to a £20 cashback total - two months on pending and two months for the cheque. And in four months time how do I know that they are not going to remove again some of the cashback I've earned so that my total dips below £20 again? In theory it could take years and years to get my cashback during which time even larger parts of the UK will be under water.
All I can conclude is to recommend that nobody becomes a member of this site.
I have actually received my £20 cheque. I eventually received a reply to my emails coincidently a week or two after I wrote this review. Apparently there had been some fault in the calculations and there had been a delay in their response due to their offices being flooded.
My conclusion is still the same because there is simply no excuse for these sites to hold on to member's money for so long. Some sites pay straight away so why can't they all do the same?
I am beginning to think this site is a con. You need to earn £20..0 before they pay out. I have £11.56 in my account so far. 4 months ago I joined Virgin Poker through the site, this should have earned me £20.00 and therefore putting me over the amount so I should get paid.
I e-mailed them about the lack of payment they then said they had not tracked the sign up to Virgin. I have kept the e-mail in June they sent me and the following days confirmation from Virgin that I have joined.
I have since sent several e-mails asking about the status of payment I dont even get a reply. It looks to me that once you get near to the amount they have to pay out then they dont respond at all.
Many other sites that seem to play fair.
Kind Regards
I think that Myshoppingrewards.com is one of the better cashback sites.
It has a huge number of shops and outlets that provide cashback either as a percentage ranging from 0.5% to upwards of 5%, or as a lumpsum. I recently changed my car insurance and because I dir it through myshoppingrewards.com I gained £50 cashback making the overall cost of the insurance a lot tedious.
You can also gain small amounts og money by conducting searches through search engines such as Buy Central, the High Street Web and Kelkoo. It is a bit tedious but can bring in about 25p a day which soon adds up. Unfortunately, sometimes you do not always get all the points you think you should.
There is also cashback for joining survey and competition sites and for entering competitions.
When you first sign up you get a £3.50 joining bonus and the opportunity to sign up for various other newsletters at 5p a time. Also there is £8 to be gained for every friend you refer. If you decide to join up I would love to refer you! Contact me here first!
It all sounds very good but the downside is that you have to wait until you have £20 in your account before you are sent a cheque. Not too bad you might say but it also takes them about two months to confirm each payment even though the casback is credited within two days normally. Therefore although you might have reached the magical £20 fairly quickly you then have to wait another two months before you receive your money!
Having said that I still think that it is a good site and I feel quite loyal to it. If you shop online regularly it is always worth seeing if you can go through Myshoppingrewards first. And the money does add up! I have been a member since February and fully expect that by Christmas I will have earned about £125+.
MyShoppingRewards.com to me was one of the best things that came out of Sweet Collect. This is how I got to hear about them it was when I was signing up with Sweet Collect that I registered with My Shopping Rewards (MSR).
MSR is an internet loyalty site which rewards you in cash, yes I can hear you all saying not another one of these con sites but this one isnt.
First of all when you register you are given £3.50 as a bonus then you can choose to join other websites etc that will get you more cash back and this wont cost you a penny. You can also get cash rewards when you shop online from stores such as HMV and Woolworths in fact there are over 500 cash back sites linked with MSR. You will only get the cash back if you go through the link on MSR.
How it works is as you are going through the MSR link this registers with then and the retailer gives MSR commission for this which they then pass some onto you.
Registering is easy just go to the home page and click the join button it is a simple and quick process and the form is self explanatory. You will be sent an activation email which you must do in order to access your account.
The home page is well set out and is very colourful but not overpowering, I find it easy to navigate through each section.
Along the top are the main categories and they are coloured green. Down the left hand side of the screen you will at first come to the offer of the week which is usually relating to applying for credit cards etc. Then you come to the shop category section which is set alphabetically or you can click all shops and then choose the letter of the shop you are looking for.
There are categories such as Easy Cash and Free Stuff this means that you have to join other websites or perhaps just do a search for which you have your daily clicks and can add any site you visit regularly to your favourites.
Down the right hand side of the screen is your login space and a list of the latest offers its worth a while taking a look here as sometimes I have found something that stands out to me.
Once you have logged in this area shows your account details and is updated each day so if you click on your account balance it takes you to another screen where there are 4 coloured headings.
Total - blue
Confirmed - Green
Pending - yellow
Reversed - Red
Now here is where I should tell you of a downside of the site in that it takes 60 days for any payments to be classed as confirmed this is just in case you send anything back etc. If you return anything etc then it goes into the reverse section.
There is a payment date each month and once you have reached £20 minimum in your confirmed section you are paid by cheque the following payday which is usually the first working day of each month but if you go to the home page it will give you the next date.
Now you can refer a friend and when they join up and gets their first £20 confirmed you get £8 into your account yes I know this could take a while but if both of you do a lot of shopping online it will be worth it.
Well there is nothing else I can really tell you about this site apart from if you want to join and want a refer link I will add it to the bottom of this review.
Here is my refer code if you want to join up feel free to use this link


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High school quiz teams from Fayette and Evergreen competed in two tournaments this year.
Archbold won the Fulton County event Dec. 5, followed by Pettisville and Wauseon.
On Nov. 4, Patrick Henry won the Henry/Fulton County tournament, followed by Archbold and Evergreen.
The Northwest Ohio Educational Service Center (NwOESC) coordinates the events.
Fayette's Quiz Team members are Jesse Torres, Amanda Gilmore, Riley Martin, Thomas Ehman, Ben Greiser, Nathaniel Harvey, Ian Schrock and Collin McCabe, with Sarah Altstaetter serving as advisor.
Evergreen's members are Graham Avina, Chey Knapp, Melisa Lyons, Zac Miller, Dylon Nevers, Nick Pupos, Jacob Vanloocke, Spencer Frederick, Devon Kurland, Ben Vasko, Remy Cousino, Renee Louy, Kyle Harmon, Nick Hendricks, Darin Kurland, Andrew Markley, Chelsey Miller and Sam Pennington, with Bill Blanchong serving as advisor.


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Express. Home of the Daily and Sunday Express.
Man United and Liverpool target Robert Lewandowski discusses Bayern Munich exit
ROBERT LEWANDOWSKI wants to stay at Bayern Munich despite interest from the Premier League.
The Poland hit-man has been linked with Liverpool and Manchester United.
His stunning form for Munich has also seen him become the latest centre forward linked with Real Madrid.
Lewandowski has scored 31 goals in 31 games for Bayern this season.
He said: "I know there has been interest from other clubs, but, right now, I see myself signing a contract extension with Bayern because we have a great club.
"This club understands how to repay great actions by their players."
Robert Lewandowski admits he wants to stay at Bayern
And the former Dortmund man had a dig at the Premier League for trying to blow the other nations out the water.
He added: "I can see the club has a firm project and is preparing for the future.
"The new deals for (Jerome) Boateng and (Thomas) Muller are a good sign that want to keep their best players despite the money being offered in England."


text: Just got certified in Mosquito and Aquatic. I would like to know what everyone is using for insecticide. Im thinking about Demand or Suspend here in WI. Im just going to be spraying homes and for like parties or weddings. How much should I charge per sq ft? Any help on this subject woulb be helpful since this is new to my business. Thanks.


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New Delhi: Denim jeans, shirts, skirts never go out of style. However, denims need an update from time to time, especially when there's a handful of fresh new trends that are influencing the look.
Rohan Seam, Head of Design, American Swan, suggests a few denim looks that can be sported:
Denim looks for men:
* Fashion is definitely getting a makeover but you can never go wrong with a classic pair of jeans. Wear it with a cool graphic tee and canvas shoes and add an edge to your overall look.
* Give your off-duty separates a refreshing look by wearing a medium blue denim jeans. This wash is made to replicate the jeans you've had forever, with some artful destruction and expert repairs.
* Distressed jeans are high on the trend game. Flaunt these with a casual printed tee and white sneaks.
* Ripped in all the right places, the messier-the-better jeans make you look chic.


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