2,718 research outputs found
Antenna Considerations for Emerging Implanted Biosensor and Intra-Body Network Applications (Abstract)
The Regulation Of Non-Profit Organizations
The absence of governmental oversight and regulation of Not-For-Profit corporations has resulted in these entities performing their stated purposes inadequately and inefficiently and has enabled financial indiscretions which have tarnished their reputations. Enhanced oversight and regulation is needed to prevent recurrences of these failures
Comparison of histomorphology and DNA preservation produced by fixatives in the veterinary diagnostic laboratory setting
Histopathology is the most useful tool for diagnosis of a number of diseases, especially cancer. To be effective, histopathology requires that tissues be fixed prior to processing. Formalin is currently the most common histologic fixative, offering many advantages: it is cheap, readily available, and pathologists are routinely trained to examine tissues fixed in formalin. However, formalin fixation substantially degrades tissue DNA, hindering subsequent use in diagnostics and research. We therefore evaluated three alternative fixatives, TissueTek® Xpress® Molecular Fixative, modified methacarn, and PAXgene®, all of which have been proposed as formalin alternatives, to determine their suitability for routine use in a veterinary diagnostic laboratory. This was accomplished by examining the histomorphology of sections produced from fixed tissues as well as the ability to amplify fragments from extracted DNA. Tissues were sampled from two dogs and four cats, fixed for 24–48 h, and processed routinely. While all fixatives produced acceptable histomorphology, formalin had significantly better morphologic characteristics than the other three fixatives. Alternative fixatives generally had better DNA amplification than formalin, although results varied somewhat depending on the tissue examined. While no fixative is yet ready to replace formalin, the alternative fixatives examined may be useful as adjuncts to formalin in diagnostic practices
Snowy Plover Nest Site Selection, Spatial Patterning, and Temperatures in the Southern High Plains of Texas
Snowy plover (Charadrius nivosus) populations have declined throughout their range, in part because of habitat degradation and poor nest success, making information regarding regionally specific nest site selection and spatial patterns important when considering habitat conservation and management guidelines. We determined nest site selection characteristics (n=80) and examined spatial patterns (n=215) of snowy plover nests in saline lakes in the Southern High Plains (SHP) of Texas. At 104 nests, we examined the influence of substrate type on nest temperatures and heat mitigation. Snowy plover nests were more likely to be found near an object, on pebble substrate, and with fewer plants than random sites. High use areas were generally located in areas with pebble substrate and on human-made or natural islands, berms, and peninsulas. Overall, nests placed on pebble substrate had lower temperatures during the day than nests placed on sand substrates. Nest placement on pebble substratemay be valuable to nesting snowy plovers, providing thermal advantages to incubating adults and depressing potentially high nest predation rates. Management guidelines for this region should emphasize the importance of addressing key elements of snowy plover nesting habitat including the presence of pebble substrate and reducing vegetation encroachment
Clinical Significance of Sleep Desaturation in Hypoxemic Chronic Obstructive Pulmonary Disease: Studies in 130 Patients
We studied 130 patients with hypoxemic chronic obstructive lung disease to determine if nocturnal desaturation aggravates hypoxia-induced complications. All had tests of neuropsychological and physiological function known to be affected by chronic hypoxia. Of the 130 patients, 25 had complete polysomnography and 105 had their sleep judged visually and arterial oxygen saturation recorded continuously. Severe and mild desaturation groups were defined relative to the mean for both mean and maximal sleep desaturation, and the severity of waking complications were compared. No significant differences were noted between patients with mild and severe mean desaturation or maximal desaturation for hematocrit, neuropsychological tests, maximal exercise tolerance, or measures of quality of life. Waking pulmonary artery pressure did not differ significantly between patients with mild and severe mean desaturation or maximal desaturation, except in 20 patients with the most severe mean desaturation during sleep. We conclude that nocturnal desaturation does not aggravate hypoxia-induced complications in most patients who are chronically hypoxemic from chronic obstructive pulmonary disease
Seasonal variation in offspring sex ratio in the Snowy Plover
The Snowy Plover (Charadrius nivosus) is unique in being a determinate layer of an odd modal clutch size and in having a variable mating system in which female brood desertion occurs regularly. These traits make determining Snowy Plover offspring sex ratios important not only for long-term population stability, as the species is of conservation concern, but also for application to sex allocation theory. In this study, we determined Snowy Plover offspring sex ratios, examined differential costs of producing male and female offspring, and evaluated sex ratio variation in relation to maternal condition, habitat condition, and time during the nesting season on saline lakes of the Southern High Plains of Texas. Examination of 245 chicks from 118 clutches during 1999–2000 and 2008–2009 showed that male offspring were more costly to produce than female offspring; however, offspring sex ratio did not differ from parity, but was slightly male-biased in most years. The probability of producing a male offspring was greater both earlier and later in the breeding season than in the middle. As the availability of saline lake surface water and the subsequent availability of food vary unpredictably throughout the breeding season, depending on precipitation events, we suggest that sex ratio adjustment in unpredictable environments may not be straightforward and may follow nonlinear models and/or vary annually. The effects such changes in sex ratios may have on population growth and stability remain unknown
Iceberg Hashing: Optimizing Many Hash-Table Criteria at Once
Despite being one of the oldest data structures in computer science, hash
tables continue to be the focus of a great deal of both theoretical and
empirical research. A central reason for this is that many of the fundamental
properties that one desires from a hash table are difficult to achieve
simultaneously; thus many variants offering different trade-offs have been
proposed.
This paper introduces Iceberg hashing, a hash table that simultaneously
offers the strongest known guarantees on a large number of core properties.
Iceberg hashing supports constant-time operations while improving on the state
of the art for space efficiency, cache efficiency, and low failure probability.
Iceberg hashing is also the first hash table to support a load factor of up to
while being stable, meaning that the position where an element is
stored only ever changes when resizes occur. In fact, in the setting where keys
are bits, the space guarantees that Iceberg hashing offers,
namely that it uses at most bits to
store items from a universe , matches a lower bound by Demaine et al.
that applies to any stable hash table.
Iceberg hashing introduces new general-purpose techniques for some of the
most basic aspects of hash-table design. Notably, our indirection-free
technique for dynamic resizing, which we call waterfall addressing, and our
techniques for achieving stability and very-high probability guarantees, can be
applied to any hash table that makes use of the front-yard/backyard paradigm
for hash table design
A Double-Blind Trial of Protriptyline in the Treatment of Sleep Apnea Syndrome
Eight male subjects with sleep apnea syndrome were given placebo and protriptyline in a double-blind crossover design to evaluate the effects of protriptyline on respiration during sleep. Treatment with protriptyline produced significantly better oxygenation and significantly fewer arousals during sleep, but sleep staging was unchanged. The decreased number of respiratory events approached significance and was much greater in six of eight subjects. A rapid eye movement sleep-suppression explanation of the improvement in oxygenation is not supported. Alternative explanations of these findings are discussed
Change in health-related quality of life in the context of pediatric obesity interventions: A meta-analytic review.
Objective: To quantitatively characterize change in health-related quality of life (HRQoL) in the context of behavioral (n = 16), surgical (n = 5), and pharmacological (n = 1) interventions for pediatric overweight and obesity. A secondary goal was to examine the relationship between change in HRQoL and change in body mass index (ΔBMI) by treatment type. The amount of weight loss necessary to observe a minimally clinically important difference (MCID) in HRQoL was determined. Method: Data were gathered from studies reporting on weight change and ΔHRQoL over the course of obesity interventions (N = 22) in youths (N = 1,332) with average ages between 7.4 and 16.5 years (M = 12.2). An overall effect size was calculated for ΔHRQoL. Moderation analyses were conducted using analysis of variance and weighted regression. MCID analyses were conducted by converting HRQoL data to standard error of measurement units. Results: The overall effect size for ΔHRQoL in the context of pediatric obesity interventions was medium (g = 0.51). A significant linear relationship was detected between ΔBMI and ΔHRQoL (R2 = 0.87). This relationship was moderated by treatment type, with medical (i.e., surgical) interventions demonstrating a stronger relationship. Results indicated that it takes a change of 0.998 BMI units to detect true change in HRQoL. Conclusion: This study provides the first known quantitative examination of changes in HRQoL associated with weight loss in pediatric interventions. Medical interventions appear to offer a more substantial increase in HRQoL per unit of BMI change. These results offer a concrete weight loss goal for noticing positive effects in daily life activities. (PsycINFO Database Record (c) 2016 APA, all rights reserved
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