1,297 research outputs found
A Systematic Review of Mosquito Coils and Passive Emanators: Defining Recommendations for Spatial Repellency Testing Methodologies.
Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propose scientific consensus on terminologies and methodologies used for evaluation of product formats that could contain spatial chemical actives, including indoor residual spraying (IRS), long lasting insecticide treated nets (LLINs) and insecticide treated materials (ITMs). PubMed, (National Centre for Biotechnology Information (NCBI), U.S. National Library of Medicine, NIH), MEDLINE, LILAC, Cochrane library, IBECS and Armed Forces Pest Management Board Literature Retrieval System search engines were used to identify studies of pyrethroid based coils and emanators with key-words "Mosquito coils" "Mosquito emanators" and "Spatial repellents". It was concluded that there is need to improve statistical reporting of studies, and reach consensus in the methodologies and terminologies used through standardized testing guidelines. Despite differing evaluation methodologies, data showed that coils and emanators induce mortality, deterrence, repellency as well as reduce the ability of mosquitoes to feed on humans. Available data on efficacy outdoors, dose-response relationships and effective distance of coils and emanators is inadequate for developing a target product profile (TPP), which will be required for such chemicals before optimized implementation can occur for maximum benefits in disease control
Perceptual Compressive Sensing
Compressive sensing (CS) works to acquire measurements at sub-Nyquist rate
and recover the scene images. Existing CS methods always recover the scene
images in pixel level. This causes the smoothness of recovered images and lack
of structure information, especially at a low measurement rate. To overcome
this drawback, in this paper, we propose perceptual CS to obtain high-level
structured recovery. Our task no longer focuses on pixel level. Instead, we
work to make a better visual effect. In detail, we employ perceptual loss,
defined on feature level, to enhance the structure information of the recovered
images. Experiments show that our method achieves better visual results with
stronger structure information than existing CS methods at the same measurement
rate.Comment: Accepted by The First Chinese Conference on Pattern Recognition and
Computer Vision (PRCV 2018). This is a pre-print version (not final version
Simpson's Paradox, Lord's Paradox, and Suppression Effects are the same phenomenon – the reversal paradox
This article discusses three statistical paradoxes that pervade epidemiological research: Simpson's paradox, Lord's paradox, and suppression. These paradoxes have important implications for the interpretation of evidence from observational studies. This article uses hypothetical scenarios to illustrate how the three paradoxes are different manifestations of one phenomenon – the reversal paradox – depending on whether the outcome and explanatory variables are categorical, continuous or a combination of both; this renders the issues and remedies for any one to be similar for all three. Although the three statistical paradoxes occur in different types of variables, they share the same characteristic: the association between two variables can be reversed, diminished, or enhanced when another variable is statistically controlled for. Understanding the concepts and theory behind these paradoxes provides insights into some controversial or contradictory research findings. These paradoxes show that prior knowledge and underlying causal theory play an important role in the statistical modelling of epidemiological data, where incorrect use of statistical models might produce consistent, replicable, yet erroneous results
High frequencies of elevated alkaline phosphatase activity and rickets exist in extremely low birth weight infants despite current nutritional support
<p>Abstract</p> <p>Background</p> <p>Osteopenia and rickets are common among extremely low birth weight infants (ELBW, <1000 g birth weight) despite current practices of vitamin and mineral supplementation. Few data are available evaluating the usual course of markers of mineral status in this population. Our objectives in this study were to determine the relationship between birth weight (BW) and peak serum alkaline phosphatase activity (P-APA) in ELBW infants and evaluate our experience with the diagnosis of rickets in these infants.</p> <p>Methods</p> <p>We evaluated all ELBW infants admitted to Texas Children's Hospital NICU in 2006 and 2007. Of 211 admissions, we excluded 98 patients who were admitted at >30 days of age or did not survive/stay for >6 weeks. Bone radiographs obtained in 32 infants were reviewed by a radiologist masked to laboratory values.</p> <p>Results</p> <p>In this cohort of 113 infants, P-APA was found to have a significant inverse relationship with BW, gestational age and serum phosphorus. In paired comparisons, P-APA of infants <600 g (957 ± 346 IU/L, n = 20) and infants 600–800 g (808 ± 323 IU/L, n = 43) were both significantly higher than P-APA of infants 800–1000 g (615 ± 252 IU/L, n = 50), p < 0.01. Thirty-two patients had radiographic evaluation for evidence of rickets, based on P-APA greater than 800 IU/L, parenteral nutrition greater than 3 to 4 weeks, or clinical suspicion. Of these, 18 showed radiologic rickets and 14 showed osteopenia without rickets. Infants with BW <600 g were more likely to have radiologic rickets (10/20 infants) compared to those with BW 600–800 g (6/43 infants) and BW 800–1000 g (2/50 infants), p < 0.01 for each. P-APA was not significantly higher in infants with radiologic rickets (1078 ± 356 IU/L) compared to those without radiologic evidence of rickets (943 ± 346, p = 0.18).</p> <p>Conclusion</p> <p>Elevation of P-APA >600 IU/L was very common in ELBW infants. BW was significantly inversely related to both P-APA and radiologic rickets. No single value of P-APA was related to radiological findings of rickets. Given the very high risk of osteopenia and rickets among ELBW infants, we recommend consideration of early screening and early mineral supplementation, especially among infants <600 g BW.</p
Effects of spoilage on nitrogen and carbon stable isotopes signatures of the clam Ruditapes decussatus
Fish and seafood products are highly susceptible to post-mortem
spoilage due to autolytic reactions at start, then microbiological activity and
eventually oxidative reactions. Chemical and microbiological parameters are
usually used to assess quality and make decisions for protecting public health,
but they lack precision in defining which spoilage pathway is occurring at each
moment. The objective of this work was to assess the effects of spoilage reactions
on nitrogen and carbon stable isotopes in the grooved carpet shell clam,
Ruditapes decussatus, and compare them to biochemical indicators of seafood
deterioration, in order to better understand the relations between the different
spoilage pathways during commercial storage conditions. Clams were kept in a
refrigerator at 5 ºC, to simulate normal commercial storage conditions, and
sampled in the beginning of the experiment, and after eight, ten and twelve
days. Moisture, condition index, percentage edibility, total volatile basic nitrogen
(TVB-N), pH, nitrogen and carbon percentages and stable isotopes were determined
for each sampling moment. Stable isotope analyses were performed
using a Costech Elemental Analyzer (ECS 4010) coupled to a ThermoFinnigan
Delta V Advantage. Stable isotopes analysis, especially for nitrogen, proved to
be a good tool for the study of clam deterioration. Nitrogen stable isotopes results
showed a relation with other spoilage indicators, such as pH and TVB-N,
and allowed identifying spoilage specific pathways, such as amino acids decarboxylation
and production of volatile nitrogen compounds.info:eu-repo/semantics/publishedVersio
GPR30, the Non-Classical Membrane G Protein Related Estrogen Receptor, Is Overexpressed in Human Seminoma and Promotes Seminoma Cell Proliferation
BACKGROUND: Testicular germ cell tumours are the most frequent cancer of young men with an increasing incidence all over the world. Pathogenesis and reasons of this increase remain unknown but epidemiological and clinical data have suggested that fetal exposure to environmental endocrine disruptors (EEDs) with estrogenic effects, could participate to testicular germ cell carcinogenesis. However, these EEDs (like bisphenol A) are often weak ligands for classical nuclear estrogen receptors. Several research groups recently showed that the non classical membrane G-protein coupled estrogen receptor (GPER/GPR30) mediates the effects of estrogens and several xenoestrogens through rapid non genomic activation of signal transduction pathways in various human estrogen dependent cancer cells (breast, ovary, endometrium). The aim of this study was to demonstrate that GPER was overexpressed in testicular tumours and was able to trigger JKT-1 seminoma cell proliferation. RESULTS: We report here for the first time a complete morphological and functional characterization of GPER in normal and malignant human testicular germ cells. In normal adult human testes, GPER was expressed by somatic (Sertoli cells) and germ cells (spermatogonia and spermatocytes). GPER was exclusively overexpressed in seminomas, the most frequent testicular germ cell cancer, localized at the cell membrane and triggered a proliferative effect on JKT-1 cells in vitro, which was completely abolished by G15 (a GPER selective antagonist) and by siRNA invalidation. CONCLUSION: These results demonstrate that GPER is expressed by human normal adult testicular germ cells, specifically overexpressed in seminoma tumours and able to trigger seminoma cell proliferation in vitro. It should therefore be considered rather than classical ERs when xeno-estrogens or other endocrine disruptors are assessed in testicular germ cell cancers. It may also represent a prognosis marker and/or a therapeutic target for seminomas
An exploration into the impact of exposure to community violence and hope on children's perceptions of well-being: a South African perspective
The study aims to explore the relationship between exposure to community
violence, hope, and well-being. More specifically, the study aims to ascertain whether
hope is a stronger predictor of well-being than exposure to violence. Stratified
random sampling was used to select a sample of 566 adolescents aged 14–17 years,
from both high violence and low violence areas in Cape Town, South Africa. A
questionnaire consisting of Snyder’s Children’s Hope Scale, the Recent Exposure to
Violence Scale and the KIDSCREEN-52 was used. Data analysis techniques included
descriptive statistics, correlations, and multiple regression. A positive, significant
relationship was found between children’s hope and their well-being. Although
exposure to community violence was found to be significantly correlated with wellbeing,
the relationship was negligible.While exposure to community violence and hope
were found to be significant predictors of well-being, hope emerged as a stronger
predictor of child well-being than exposure to community violence.Department of HE and Training approved lis
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