277 research outputs found

    The Noninvasive Measurement of Central Aortic Blood Pressure Waveform

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    Central aortic pressure (CAP) is a potential surrogate of brachial blood pressure in both clinical practice and routine health screening. It directly reflects the status of the central aorta. Noninvasive measurement of CAP becomes a crucial technique of great interest. There have been advances in recent years, including the proposal of novel methods and commercialization of several instruments. This chapter briefly introduces the clinical importance of CAP and the theoretical basis for the generation of CAP in the first and second sections. The third section describes and discusses the measurement of peripheral blood pressure waveforms, which is employed to estimate CAP. We then review the proposed methods for the measurement of CAP. The calibration of blood pressure waveforms is discussed in the fourth section. After a brief discussion of the technical limitations, we give suggestions for perspectives and future challenges

    Mapping genes with longitudinal phenotypes via Bayesian posterior probabilities

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    Most association studies focus on disease risk, with less attention paid to disease progression or severity. These phenotypes require longitudinal data. This paper presents a new method for analyzing longitudinal data to map genes in both population-based and family-based studies. Using simulated systolic blood pressure measurements obtained from Genetic Analysis Workshop 18, we cluster the phenotype data into trajectory subgroups. We then use the Bayesian posterior probability of being in the high subgroup as a quantitative trait in an association analysis with genotype data. This method maintains high power (\u3e80%) in locating genes known to affect the simulated phenotype for most specified significance levels (a). We believe that this method can be useful to aid in the discovery of genes that affect severity or progression of disease

    Magnetic Properties of Ni-doped ZnO Nanocombs by CVD Approach

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    The search for above room temperature ferromagnetism in dilute magnetic semiconductors has been intense in recent year. Arrays of perpendicular ferromagnetic nanowire/rods have recently attracted considerable interest for their potential use in many areas of advanced nanotechnology. We report a simple low-temperature chemical vapor deposition (CVD) to create self-assembled comb-like Ni-/undoped ZnO nanostructure arrays. The phases, compositions, and physical properties of the studied samples were analyzed by different techniques, including high-resolution X-ray diffraction/photoelectron spectroscopy/transmission electron microscopy, photoluminescence, and MPMS. In particular, the Ni-doped ZnO nanocombs (NCs) with ferromagnetic and superparamagnetic properties have been observed whereas undoped ZnO NCs disappear. The corresponding ferromagnetic source mechanism is discussed, in which defects such as O vacancies would play an important role

    Validation of an adaptive transfer function method to estimate the aortic pressure waveform

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    Aortic pulse wave reflects cardiovascular status, but, unlike the peripheral pulse wave, is difficult to be measured reliably using noninvasive techniques. Thus, the estimation of aortic pulse wave from peripheral ones is of great significance. This study proposed an adaptive transfer function (ATF) method to estimate the aortic pulse wave from the brachial pulse wave. Aortic and brachial pulse waves were derived from 26 patients who underwent cardiac catheterization. Generalized transfer functions (GTF) were derived based on the autoregressive exogenous model. Then, the GTF was adapted by its peak resonance frequency. And the optional peak resonance frequency for an individual was determined by regression formulas using brachial systolic blood pressure. The method was validated using the leave-one-out cross validation method. Compared with previous studies, the ATF method showed better performance in estimating the aortic pulse wave and predicting the feature parameters. The prediction error of the aortic systolic blood pressure and pulse pressure were 0.2 ± 3.1 and -0.9 ± 3.1 mmHg, respectively. The percentage errors of augmentation index, percentage notch amplitude, and ejection duration were -2.1 ± 32.7%, 12.4 ± 9.2%, and -2.4 ± 3.3%, respectively

    Generating Electrospray Ionization on Ballpoint Tips

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    Pharmacy students’ attitudes and perceptions toward pharmacogenomics education

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    Purpose To evaluate final-year pharmacy students’ perceptions toward pharmacogenomics education, their attitudes on its clinical relevance, and their readiness to use such knowledge in practice. Methods A 19-question survey was developed and modified from prior studies and was pretested on a small group of pharmacogenomics faculty and pharmacy students. The final survey was administered to 978 final-year pharmacy students in 8 school/colleges of pharmacy in New York and New Jersey between January and May 2017. The survey targeted 3 main themes: perceptions toward pharmacogenomics education, attitudes toward the clinical relevance of this education, and the students’ readiness to use knowledge of pharmacogenomics in practice. Results With a 35% response rate, the majority (81%) of the 339 student participants believed that pharmacogenomics was a useful clinical tool for pharmacists, yet only 40% felt that it had been a relevant part of their training. Almost half (46%) received only 1–3 lectures on pharmacogenomics and the majority were not ready to use it in practice. Survey results pointed toward practice-based trainings such as pharmacogenomics rotations as the most helpful in preparing students for practice. Conclusions Final-year student pharmacists reported varying exposure to pharmacogenomics content in their pharmacy training and had positive attitudes toward the clinical relevance of the discipline, yet they expressed low confidence in their readiness to use this information in practice

    Linking life table and predation rate for evaluating temperature effects on Orius strigicollis for the biological control of Frankliniella occidentalis

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    IntroductionOrius spp. are generalist predators released in horticultural and agricultural systems to control thrips. Understanding the effects of temperature on the development, predation rate, and population dynamics of Orius is essential for identifying the optimal timing of Orius release for establishing an adequate population to facilitate synchrony with thrips population growth and to prevent thrips outbreaks. The biological control efficiency of natural enemies as well as predator–prey relationships can be precisely described by integrating life table parameters and the predation rate.MethodsIn this study, the demographic features of Orius strigicollis fed on 2nd instar nymphs of western flower thrips (WFT), Frankliniella occidentalis, were compared at 18.5, 23.5, 27, and 33°C using the TWOSEX-MSChart program. The CONSUME-MSChart program was used to examine predation rates under different temperatures (18.5, 23.5, and 27°C).ResultsThe results showed no significant difference in fecundity among those reared at 18.5, 23.5, and 27°C, but fecundity at these temperatures was significantly higher than that at 33°C. The intrinsic rate of increase (r), finite rate of increase (λ), and net reproduction rate (R0) were the highest at 27°C. The net predation rate (C0) and transformation rate (Qp) were significantly higher at 18.5°C (C0 = 168.39 prey/predator, Qp = 8.22) and 23.5°C (C0 = 140.49 prey/predator, Qp = 6.03) than at 27°C (C0 = 138.39 prey/predator, Qp= 3.81); however, the finite predation rate (ω) showed the opposite trend. In addition to temperature, the stage of O. strigicollis at release can affect population dynamics.DiscussionOur study showed that temperature influenced the demographic traits and predation rates of O. strigicollis. When planning a release, the stage of O. strigicollis and temperature should be taken into account to establish an adequate population for the control of WFT
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