Insulated ECG electrodes

Insulated, capacitively coupled electrode does not require electrolyte paste for attachment. Other features of electrode include wide range of nontoxic material that may be employed for dielectric because of sputtering technique used. Also, electrode size is reduced because there is no need for external compensating networks with FET operational amplifier

Insulated electrocardiographic electrodes

An integrated system is disclosed including an insulated electrode and an impedance transformer which can be assembled in a small plastic housing and used for the acquisition of electrocardiographic data. The electrode may be employed without a paste electrolyte and may be attached to the body for extended usage without producing skin reaction. The electrode comprises a thin layer of suitable nontoxic dielectric material preferably deposited by radio frequency sputtering onto a conductive substrate. The impedance transformer preferably comprises an operational amplifier having an FET input stage connected in the unity gain configuration which provides a very low lower cut-off frequency, a high input impedance with a very small input bias current, a low output impedance, and a high signal-to-noise ratio

The development of insulated electrocardiogram electrodes

An integrated system was developed, consisting of an insulated electrode and an impedance transformer, which can be used for the acquisition of electrocardiographic data. The electrode consists of a thin layer of dielectric material deposited onto a silicon substrate. The impedance transformer is an operational amplifier used in the unity gain configuration. Both electrode and impedance transformer are contained in a plastic housing identical to that used with the NASA Apollo-type electrode. The lower cut off frequency of the electrode system is between 0.01 and 1.0 Hz, depending on the dielectric used and its thickness. Clinical quality electrocardiograms were obtained with these electrodes

Understanding the reproductive behavior and population condition of the sandbar shark (Carcharhinus plumbeus) in the western North Atlantic: A molecular approach to conservation and management

The sandbar shark, Carcharhinus plumbeus, has a discontinuous cosmopolitan distribution and is exploited throughout much of its range. In the western North Atlantic, it constitutes the majority of the directed commercial fishery. The stock has declined greatly since the fisheries\u27 inception and has not shown signs of recovery despite the implementation of management practices. Like many highly vagile marine species, it is difficult to obtain information about the sandbar shark through direct observation. Therefore, the goal of this dissertation is to use a molecular approach to examine aspects of behavior and reproduction, providing information useful in conservation and management. to this end, I examine the prevalence of genetic polyandry in the western North Atlantic and estimate effective population size and effective number of breeders for the Delaware Bay and Eastern Shore of Virginia nursery grounds. In addition, I look at patterns of philopatry and reproductive periodicity, while on a worldwide scale, assessing both historical and contemporary gene flow. Paternity analysis using microsatellite markers reveals that most females are mate with multiple males during one reproductive period. Despite the high prevalence of genetic polyandry, no direct benefits are detected. The data, however, suggest that males benefit by excluding other males from mating, intimating strong intrasexual competition. The effective number of breeders per nursery ground, estimated using the linkage disequilibrium method, is fairly consistent across years. Comparisons with census size estimates made for Delaware Bay reveal that the two measurements are tightly coupled. The ratio of effective size to census size is 0.45 or higher. This suggests that monitoring of effective population size may be a useful methodology for tracking abundance, and that exploitation may have a direct negative impact on the level of genetic variance. The results suggest that females may stray between nursery grounds found in Delaware Bay, the Eastern Shore lagoons and Chesapeake Bay, as phi st values are nonsignificant and kin groups are detected between as well as within samples. However, true kin groups can not be distinguished from erroneous kin groups because sample size is too small and the loci employed do not have enough power. Even so, the results suggest that female reproductive periodicity in this species needs to be reevaluated. Different patterns of historical dispersal and contemporary gene flow are observed when markers with different modes of inheritance are used to evaluate historical phylogeography. The results suggest that, although females show regional phylopatry, pulses of female dispersal during the Pleistocene may have created the species\u27 current distribution. This dynamic may have been mediated by the changing distribution of nursery habitat caused by the rise and fall of sea level associated with climate change rather than by fluctuating temperature. This idea is supported by the results, which suggest that male mediated gene flow persists long after female gene flow has stopped

Dixie Lullaby

https://digitalcommons.library.umaine.edu/mmb-vp/4180/thumbnail.jp

These aren’t the loci you’re looking for: Principles of effective SNP filtering for molecular ecologists

Sequencing reduced‐representation libraries of restriction site‐associated DNA (RADseq) to identify single nucleotide polymorphisms (SNPs) is quickly becoming a standard methodology for molecular ecologists. Because of the scale of RADseq data sets, putative loci cannot be assessed individually, making the process of filtering noise and correctly identifying biologically meaningful signal more difficult. Artefacts introduced during library preparation and/or bioinformatic processing of SNP data can create patterns that are incorrectly interpreted as indicative of population structure or natural selection. Therefore, it is crucial to carefully consider types of errors that may be introduced during laboratory work and data processing, and how to minimize, detect and remove these errors. Here, we discuss issues inherent to RADseq methodologies that can result in artefacts during library preparation and locus reconstruction resulting in erroneous SNP calls and, ultimately, genotyping error. Further, we describe steps that can be implemented to create a rigorously filtered data set consisting of markers accurately representing independent loci and compare the effect of different combinations of filters on four RAD data sets. At last, we stress the importance of publishing raw sequence data along with final filtered data sets in addition to detailed documentation of filtering steps and quality control measures

Modeling The Economic Burden Of Adult Vaccine-Preventable Diseases In The United States

Vaccines save thousands of lives in the United States every year, but many adults remain unvaccinated. Low rates of vaccine uptake lead to costs to individuals and society in terms of deaths and disabilities, which are avoidable, and they create economic losses from doctor visits, hospitalizations, and lost income. To identify the magnitude of this problem, we calculated the current economic burden that is attributable to vaccine-preventable diseases among US adults. We estimated the total remaining economic burden at approximately $9 billion (plausibility range:$4.7-$15.2 billion) in a single year, 2015, from vaccine-preventable diseases related to ten vaccines recommended for adults ages nineteen and older. Unvaccinated individuals are responsible for almost 80 percent, or$7.1 billion, of the financial burden. These results not only indicate the potential economic benefit of increasing adult immunization uptake but also highlight the value of vaccines. Policies should focus on minimizing the negative externalities or spillover effects from the choice not to be vaccinated, while preserving patient autonomy

Kin-Aggregations Explain Chaotic Genetic Patchiness, a Commonly Observed Genetic Pattern, in a Marine Fish

The phenomenon of chaotic genetic patchiness is a pattern commonly seen in marine organisms, particularly those with demersal adults and pelagic larvae. This pattern is usually associated with sweepstakes recruitment and variable reproductive success. Here we investigate the biological underpinnings of this pattern in a species of marine goby Coryphopterus personatus. We find that populations of this species show tell-tale signs of chaotic genetic patchiness including: small, but significant, differences in genetic structure over short distances; a non-equilibrium or “chaotic” pattern of differentiation among locations in space; and within locus, within population deviations from the expectations of Hardy-Weinberg equilibrium (HWE). We show that despite having a pelagic larval stage, and a wide distribution across Caribbean coral reefs, this species forms groups of highly related individuals at small spatial scales (metres). These spatially clustered family groups cause the observed deviations from HWE and local population differentiation, a finding that is rarely demonstrated, but could be more common than previously thought

Conduct Disorder and cognitive functioning: Testing three causal hypotheses

Studied the relation between cognitive functioning, as evidenced by IQ and achievement test performance, and Diagnostic and Statistical Manual of Mental Disorders (DSM-III) categories of conduct disturbance, using data from Black adolescents who were members of collaborative perinatal project from birth to age 7 yrs. At age 17 yrs, Ss and their parents were administered a battery of instruments that included standardized psychiatric diagnostic interviews as part of a call-back study. Analyses were compatible with the hypothesis that deficiencies in cognitive functioning are causally related to adolescent conduct disorder as defined by DSM—III. Results suggest that the relation of cognitive functioning to psychiatric status was specific to conduct disorders. Results were incompatible with the hypothesis that conduct problems lead to deficits in cognitive functioning. The 3 most important factors in accounting for age-17 conduct disorder were cognitive functioning, parent psychopathology, and early aggression