Home Blood Pressure Monitors For 21st Century

Home blood pressure monitors will play increasingly important role in 21st century healthcare. Improvements in their accuracy and reliability will be necessary. In this paper we described their function and suggested several improvements. The improvements include static accuracy check, a public database of cuff pulse waves, utilization of cuff pulse waves for several hemodynamic variables, and wider cuff for wrist monitors

Home Blood Pressure Monitors For 21st Century

Home blood pressure monitors will play increasingly important role in 21st century healthcare. Improvements in their accuracy and reliability will be necessary. In this paper we described their function and suggested several improvements. The improvements include static accuracy check, a public database of cuff pulse waves, utilization of cuff pulse waves for several hemodynamic variables, and wider cuff for wrist monitors

Male Moth Songs Tempt Females to Accept Mating: The Role of Acoustic and Pheromonal Communication in the Reproductive Behaviour of Aphomia sociella

Members of the subfamily Galleriinae have adapted to different selective environmental pressures by devising a unique mating process. Galleriinae males initiate mating by attracting females with either chemical or acoustic signals (or a combination of both modalities). Six compounds considered candidates for the sex pheromone have recently been identified in the wing gland extracts of Aphomia sociella males. Prior to the present study, acoustic communication had not been investigated. Signals mediating female attraction were likewise unknown.Observations of A. sociella mating behaviour and recordings of male acoustic signals confirmed that males initiate the mating process. During calling behaviour (stationary wing fanning and pheromone release), males disperse pheromone from their wing glands. When a female approaches, males cease calling and begin to produce ultrasonic songs as part of the courtship behaviour. Replaying of recorded courting songs to virgin females and a comparison of the mating efficiency of intact males with males lacking tegullae proved that male ultrasonic signals stimulate females to accept mating. Greenhouse experiments with isolated pheromone glands confirmed that the male sex pheromone mediates long-range female attraction.Female attraction in A. sociella is chemically mediated, but ultrasonic communication is also employed during courtship. Male ultrasonic songs stimulate female sexual display and significantly affect mating efficiency. Considerable inter-individual differences in song structure exist. These could play a role in female mate selection provided that the female's ear is able to discern them. The A. sociella mating strategy described above is unique within the subfamily Galleriinae

Model strategy for village development in the Czech Republic

The model strategies discussed in this article represent different ways of possible village development in the Czech Republic. We used typologies of strategies from business strategic management for their definition. Twenty municipalities, where structured interviews were carried out with their mayors, were chosen randomly from among 100 villages where a questionnaire survey was conducted in 2012 (Faltová Leitmanová, et al., 2012). Based on the qualitative analysis of the structured interview summaries, eight model strategies were ascertained. These include integration strategy, service differentiation, spending cuts, usage of municipal property, stabilization of village population, business support, fundraising, and identification of the inhabitants with the village (village pride). The most commonly applied model strategy is integration, followed by village population stabilization

Measuring of the operational characteristics of PV systems

Bakalářská práce pojednává o principu fotoelektrického jevu, složení fotovoltaického článku a různých typech solárních panelů. V této práci je dále zobrazen předpokládaný průběh zatěžovací charakteristiky. Jsou zde také popsány parametry ovlivňující tento průběh. V další části je popsán měřící systém, který se využívá k reálnému měření provozních charakteristik. Na konci bakalářské práce jsou uvedeny výsledky praktického měření.The bachelor's thesis deals with the principle of the photoelectric effect, the composition of the photovoltaic cell and different types of solar panels. In this project there is also displayed the expected course of the operating characteristics. There are also discussed the parameters affecting this course. In next section describes the measurement system which is used to measure real operating characteristics. At the end of bachelor's thesis are listed results of real measurement.

Operating parameters of the PV modules operating in hybrid energy systems - comparison

Diplomová práce pojednává o principu fotoelektrického jevu, složení fotovoltaického článku a různých typech solárních panelů. Je zde popsán princip přeměny větrné energie na elektrickou. Práce popisuje důvody využití hybridního systému. V další části je popsán měřící systém, který se využívá k reálnému měření provozních stavů. V poslední části je rozbor naměřených hodnot a dále jsou uvedeny faktory ovlivňující návrh hybridního energetického systému.The master’s thesis deals with the principle of the photoelectric effect, the composition of the photovoltaic cell and different types of solar panels. Here is described the principle of converting wind energy into electricity. This master’s thesis describes reasons for using of the hybrid system. The next section describes the measurement system which is used to measure real operating statuses. The last section is an analysis of measured values and there are listed factors influencing the design of hybrid power system.

The effect of wrist cuff width on oscillometric blood pressure waveforms

Accuracy of blood pressure (BP) measurement with any method is affected by cuff size. Narrow cuff overestimates BP and wide cuff underestimates BP. Wrist cuff oscillometric BP monitors typically use narrow cuffs with bladders about 6 cm wide. The segment of the radial artery compressed by the wrist cuff presents a hydraulic resistance (Rc) to blood flow during BP measurement. Narrow cuff presents smaller Rc than wide cuff. Changes in Rc alter the amplitude envelope of oscillometric waveforms. Narrow cuff allows blood flow under the cuff and into the hand sooner than wide cuff. The objective of this study was to demonstrate that narrow cuff alters the amplitude envelope in a manner that results in increased BP values when characteristic ratio algorithm is used. A specialized experimental system was used to acquire wrist oscillometric BP data from a narrow (6 cm) cuff and from a wide (10 cm) cuff. Data were acquired from 10 volunteers in sitting position. The results confirmed the objective of the study. All narrow cuff BPs were higher than either the reference BPs or wide cuff BPs. Wide cuff algorithmic BPs were similar to the reference BPs. Wider wrist cuffs appear to be desirable for improved accuracy and reliability of wrist BP monitors

The Effects and Consequences of Blood Pressure Cuff Pulse Wave Filtering

Cuff pulse waves together with cuff pressure are essential in modern automatic blood pressure (BP) devices. Most methods for BP determination employ cuff wave amplitudes. Physiological features of cuff waves have been neglected. In this study we described the origin of amplitude based approach to automatic BP determination. The cuff waves are commonly called oscillations and the methods for BP determination are called oscillometric methods. Excessive filtering of cuff waves causes obliteration of important physiological features of the waves. We introduced wider frequency band filtering that opens avenues to more sophisticated processing of cuff waves. Examples of cuff pulse wave applications beyond BP determination are shown

Determination of systolic, mean and diastolic blood pressures with Dual cuff system is based on physiology

Single cuff automatic blood pressure (BP) measurements are subject to errors because the BP values are based on statistical estimation rather than on physiological principles. We developed a dual cuff experimental system that uses an arm cuff and a wrist cuff. The wrist cuff function is similar to auscultation. This study concentrated on the determination of systolic, diastolic and mean BP using the wrist cuff pulse waveforms and the arm cuff pressures. Fifty two BP tests from our database were used to compute blood pressures using the wrist cuff method and the single arm cuff method and the two methods were compared. Mean BP values for both methods were similar but there were important individual differences. The dual cuff method should prove to be more accurate than single cuff methods because it is based on physiological principles

Development of a Public Database of Raw Data From a Blood Pressure Cuff

Pressure data acquired from a blood pressure cuff during a blood pressure test are the starting point of noninvasive, single cuff blood pressure determination. Most blood pressure devices on the market use the single cuff method. This paper describes acquisition, analog and digital processing, and storage of raw data from a blood pressure cuff during gradual cuff deflation. Raw data from 30 arm cuff tests and 20 wrist cuff tests were organized to form a database of text files. Separate annotation documents were also created. The database was uploaded to the Google Drive. The database can be downloaded by any interested party. The data can be used for the development of algorithms for blood pressure determination and for the assessment of some cardiovascular variables