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We developed an expensiveness index and used the Food Acquisition and Purchase Survey data set to examine empirically whether Supplemental Nutrition Assistance Program (SNAP) participants pay higher prices compared with nonqualifying and qualifying, but nonparticipating, households. Purchasers’ ability to minimize food expenditures has significant effects on the program’s effectiveness and on participants’ food security. Using ordinary least squares and two techniques that control for the endogeneity of SNAP participation, we found no significant effect of SNAP participation on food prices. Moreover, we found that SNAP participants pay, on average, lower prices than do nonparticipants. We conclude by providing suggestions for policy improvements and implications for future research.
Introduction: Emergency health care providers (HCPs) regularly perform difficult medical resuscitations that require complex decision making and action. Critical incident debriefing has been proposed as a mechanism to mitigate the psychological effect of these stressful events and improve both provider and patient outcomes. The purpose of this updated systematic review is to determine if HCPs performing debriefing after critical incidents, compared to no debriefing, improves the outcomes of the HCPs or patients. Methods: We performed a librarian assisted systematic review of OVID Medline, CINAHL, OVID Embase and Google Scholar (January 2006 to February 2017) No restrictions for language were imposed. Two investigators evaluated articles independently for inclusion criteria, quality and data collection. Agreement was measured using the Kappa statistic and quality of the articles were assessed using the Downs and Black evaluation tool. Results: Among the 658 publications identified 16 met inclusion criteria. Participants included physicians, nurses, allied health and learners involved in both adult and pediatric resuscitations. Findings suggest that HCPs view debriefing positively (n=7). One moderate quality study showed that debriefing can enhance medical student and resident knowledge. Several studies (n=8) demonstrated at least some improvement in CPR and intubation related technical skills. Debriefing is also associated with improved short term patient survival but not survival to discharge (n=5). Two studies reported benefits to HCPs mental health as evidenced by improved ability to manage grief and decreased reported symptoms of Post-Traumatic Stress Disorder (PTSD). Conclusion: We found HCPs value debriefing after critical incidents and that debriefing is associated with improved HCP knowledge, skill and well-being. Despite these positive findings, there continues to be limited evidence that debriefing significantly impacts long term patient outcomes. Larger scale higher quality studies are required to further delineate the effect of structured debriefing on patient and provider outcomes.
Introduction: When a female presents with abdominal pain and vaginal bleeding, a positive b-hcg level helps in the diagnosis of an ectopic pregnancy. A timely diagnosis as well as management is required for these cases. In many emergency departments, there can be delays in laboratory processing of quantitative b-hcg levels as well as qualitative urine pregnancy tests. In others, especially in rural hospitals in Canada, the laboratory closes at night and these tests cannot be processed until the morning. This may also help decrease length of stay for some patients in the emergency department. There are currently new point-of-care b-hcg tests on the market using capillary blood, but these are expensive and not readily available. The purpose of the study is to validate the most inexpensive point of care urine pregnancy tests readily available on the market for use with capillary blood samples. These point-of-care tests have only been studied with urine and whole blood. If validated with capillary blood, it would allow for a very practical, rapid, and inexpensive test which could help doctors and nurses to triage patients in a timely and more efficient fashion. Methods: In our emergency department, 385 patients between the ages of 18-50 with possible pregnancy, abdominal pain or vaginal bleeding will be included in the study. A capillary blood sample will be taken and applied to a cassette point-of-care pregnancy test with four drops of saline. Two independent investigators will assess the test. The results will be compared to a quantitative serum hCG assay and urine. If these tests are not done as part of the patients medical care, the patient will be contacted one month after to enquire if the patient is pregnant or not. The sensitivity, specificity, positive and negative predictive values will be calculated. Results: Data colleciton will begin in January 2018. Conclusion: No conclusions can yet be drawn.
To evaluate a computer-assisted point-prevalence survey (CAPPS) for hospital-acquired infections (HAIs).
A 754-bed teaching hospital in the Netherlands.
For the internal validation of a CAPPS for HAIs, 2,526 patients were included. All patient records were retrospectively reviewed in depth by 2 infection control practitioners (ICPs) to determine which patients had suffered an HAI. Preventie van Ziekenhuisinfecties door Surveillance (PREZIES) criteria were used. Following this internal validation, 13 consecutive CAPPS were performed in a prospective study from January to March 2013 to determine weekly, monthly, and quarterly HAI point prevalence. Finally, a CAPPS was externally validated by PREZIES (Rijksinstituut voor Volksgezondheid en Milieu [RIVM], Bilthoven, Netherlands). In all evaluations, discrepancies were resolved by consensus.
In our series of CAPPS, 83% of the patients were automatically excluded from detailed review by the ICP. The sensitivity of the method was 91%. The time spent per hospital-wide CAPPS was ~3 hours. External validation showed a negative predictive value of 99.1% for CAPPS.
CAPPS proved to be a sensitive, accurate, and efficient method to determine serial weekly point-prevalence HAI rates in our hospital.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
The production of livestock feed in the USA is geographically concentrated, which poses several risks. Extreme weather events and disease outbreaks have the potential to disrupt production in these areas, which could reduce the national output of meat, dairy and eggs. Additionally, geographically concentrated livestock and feed production systems have been observed to contribute excessive nutrient loads to surrounding soil and water bodies, thereby threatening environmental sustainability. Geographic relocation of production systems has been proposed as an adaptation strategy to increase system resilience and this could take the shape of more geographically dispersed livestock feed production. We estimate the degree to which the demand for meat, dairy and eggs in the Northeast region is met with current levels of regional feed and livestock production, a term that we refer to as regional self-reliance. We combine mean annual (2001–2010) data on Northeast regional land use; crop output; meat, dairy and egg output; and food consumption with a livestock feed requirements model. An annual mean of over 6.1 million ha of land in the Northeast was dedicated to livestock feed from 2001 to 2010, with nearly 80% located in just three states (Pennsylvania, New York and West Virginia). The region is a net importer of livestock feed (in terms of total digestible nutrients and crude protein), as well as meat, dairy and eggs (in terms of total human-edible energy and protein). This is the result of a confluence of long-term regional trends that include the movement of agricultural production out of the region with a concomitant increase in the regional population and an increase in the national demand for meat, dairy and eggs. Limited slaughter output in the region is a key limiting factor to increasing the region's self-reliance for livestock products.
Toxoplasma gondii and Sarcocystis neurona are protozoan parasites with terrestrial definitive hosts, and both pathogens can cause fatal disease in a wide range of marine animals. Close monitoring of threatened southern sea otters (Enhydra lutris nereis) in California allowed for the diagnosis of dual transplacental transmission of T. gondii and S. neurona in a wild female otter that was chronically infected with both parasites. Congenital infection resulted in late-term abortion due to disseminated toxoplasmosis. Toxoplasma gondii and S. neurona DNA was amplified from placental tissue culture, as well as from fetal lung tissue. Molecular characterization of T. gondii revealed a Type X genotype in isolates derived from placenta and fetal brain, as well as in all tested fetal organs (brain, lung, spleen, liver and thymus). This report provides the first evidence for transplacental transmission of T. gondii in a chronically infected wild sea otter, and the first molecular and immunohistochemical confirmation of concurrent transplacental transmission of T. gondii and S. neurona in any species. Repeated fetal and/or neonatal losses in the sea otter dam also suggested that T. gondii has the potential to reduce fecundity in chronically infected marine mammals through parasite recrudescence and repeated fetal infection.
This review offers a critical-care perspective on the pathophysiology, monitoring, and management of acute heart failure syndromes in children. An in-depth understanding of the cardiovascular physiological disturbances in this population of patients is essential to correctly interpret clinical signs, symptoms and monitoring data, and to implement appropriate therapies. In this regard, the myocardial force–velocity relationship, the Frank–Starling mechanism, and pressure–volume loops are discussed. A variety of monitoring modalities are used to provide insight into the haemodynamic state, clinical trajectory, and response to treatment. Critical-care treatment of acute heart failure is based on the fundamental principles of optimising the delivery of oxygen and minimising metabolic demands. The former may be achieved by optimising systemic arterial oxygen content and the variables that determine cardiac output: heart rate and rhythm, preload, afterload, and contractility. Metabolic demands may be decreased by a number of ways including positive pressure ventilation, temperature control, and sedation. Mechanical circulatory support should be considered for refractory cases. In the near future, monitoring modalities may be improved by the capture and analysis of complex clinical data such as pressure waveforms and heart rate variability. Using predictive modelling and streaming analytics, these data may then be used to develop automated, real-time clinical decision support tools. Given the barriers to conducting multi-centre trials in this population of patients, the thoughtful analysis of data from multi-centre clinical registries and administrative databases will also likely have an impact on clinical practice.
Using data on over 4,000 individual residential addresses, we find that geographic distance between directors and corporate headquarters is related to information acquisition and board decisions. The fraction of a board’s unaffiliated directors who live near headquarters is higher when information-gathering needs are greater. When the fraction of unaffiliated directors living near headquarters is lower, nonroutine chief executive officer (CEO) turnover is more sensitive to stock performance. Also, the level, intensity, and sensitivity of CEO equity-based pay increase with board distance. Overall, our results suggest that geographic location is an important dimension of board structure that influences directors’ costs of gathering information.
Choline is an essential nutrient that is found in many food sources and plays a critical role in the development of the central nervous system. Animal studies have shown that choline status pre- and postnatally can have long-lasting effects on attention and memory; however, effects in human subjects have not been well studied. The aim of the present study was to examine the association between plasma concentrations of free choline and its related metabolites in children and their neurodevelopment in the Seychelles Child Development Nutrition Study, an ongoing longitudinal study assessing the development of children born to mothers with high fish consumption during pregnancy. Plasma concentrations of free choline, betaine, dimethylglycine (DMG), methionine and homocysteine and specific measures of neurodevelopment were measured in 210 children aged 5 years. The children's plasma free choline concentration (9·17 (sd 2·09) μmol/l) was moderately, but significantly, correlated with betaine (r 0·24; P= 0·0006), DMG (r 0·15; P= 0·03), methionine (r 0·24; P= 0·0005) and homocysteine (r 0·19; P= 0·006) concentrations. Adjusted multiple linear regression revealed that betaine concentrations were positively associated with Preschool Language Scale – total language scores (β = 0·066; P= 0·04), but no other associations were evident. We found no indication that free choline concentration or its metabolites, within the normal physiological range, are associated with neurodevelopmental outcomes in children at 5 years of age. As there is considerable animal evidence suggesting that choline status during development is associated with cognitive outcome, the issue deserves further study in other cohorts.
Cryptosporidium is a zoonotic protozoan parasite with public health importance worldwide. The objectives of this study were to (1) conduct a meta-analysis of published literature for oocyst shedding and diarrhoea outcomes, and (2) develop recommendations for standardization of experimental dose–response studies. Results showed that for the outcome of oocyst shedding in faeces, the covariates ‘experimental species’, ‘immunosuppression’, ‘oocyst dose’ and ‘oocyst dose’ × ‘age’ were all significant (P ⩽ 0·05). This study suggests that exposing mice, piglets, or ruminants, and using immunosuppressed experimental hosts, is more likely to result in oocyst shedding. For the outcome of diarrhoea in experimentally infected animal species, the key covariates ‘experimental species’, ‘age’ and ‘immunosuppression’ were significant (P ⩽ 0·2). Therefore, based on the results of this meta-analysis, these variables should be carefully reported and considered when designing experimental dose–response studies. Additionally, detection of possible publication bias highlights the need to publish additional studies that convey statistically non-significant as well as significant results in the future.
To assess the nutritional adequacy of Seychellois children in relation to nutrients reported to be important for cognitive development.
Dietary intakes were assessed by 4 d weighed food diaries and analysed using dietary analysis software (WISP version 3·0; Tinuviel Software, UK). Individual nutrient intakes were adjusted to usual intakes and, in order to investigate adequacy, were compared with the UK Estimated Average Requirements for children aged 4–6 years.
Children 5 years old were followed up as part of the Seychelles Child Development Nutrition Study (SCDNS), located in the high-fish-consuming population of Mahé, Republic of Seychelles.
Analysis was carried out on a sample of 229 children (118 boys, 111 girls).
Children consumed a diet of which fortified cereal and milk products contributed the most to nutrient intakes. The majority (≥80 %) of children met requirements for several nutrients important for child development including Fe, folate and Se. Adjusted dietary intakes of Cu, Zn, iodine, niacin and vitamin A were below the Estimated Average Requirement or Recommended Nutrient Intake. Mean adjusted energy intakes (boys 4769 kJ/d (1139·84 kcal/d), girls 4759 kJ/d (1137·43 kcal/d)) were lower than the estimated energy requirement (boys 5104 kJ/d (1220 kcal/d), girls 5042 kJ/d (1205 kcal/d)) for 88 % of boys and 86 % of girls.
Nutrition was adequate for most children within the SCDNS cohort. Low intakes of some nutrients (including Zn, niacin and vitamin A) could reflect nutritional database inaccuracies, but may require further investigation. The study provides valuable information on the adequacy of intakes of nutrients which could affect the growth and development of Seychellois children.
The preparation of μc-Si films from SiH4-H2 mixtures by electron-cyclotron resonance (ECR) CVD at deposition temperatures ≤ 400°C on foreign substrates is reported. Deposition conditions were identified for which Si films with a high degree of crystallinity were grown as was confirmed by Raman spectroscopy. A factorial analysis was carried out, for which the influence of deposition temperature, microwave power, hydrogen dilution and total pressure on film growth were investigated. Samples of optimized crystallinity were prepared in a lowpressure and high-hydrogen dilution regime. In-plane grain sizes were measured by TEM and found to be on the order of 10 - 12 nm. Next to the optimization of crystallinity several sources of impurity contamination during film deposition were identified and eliminated. Intrinsic μc-Si layers could be prepared under these conditions that exhibited a dark conductivity σd of 2 × 10-7 S/cm and photosensitivity σph/σd of 150. It is concluded that ECR CVD is capable of producing intrinsic layers with electronic properties as necessary for use in state-of-the-art n-i-p μc-Si solar cells.
The role of the neutral dangling bond defect upon photocarrier processes in undoped amorphous hydrogenated silicon (a-Si:H) is discussed. The evidence that the dangling bond is a simple recombination center is reviewed, and it is shown that this model does not account for photocurrent response time measurements. Experimental data pertinent to the role of electrical contacts upon response time measurements are presented, and it is concluded that contact effects do not account for response-time measurements. The possibility that the dangling bond is primarily an electron trap is discussed.
Drift-mobility measurements in undoped amorphous hydrogenated silicon (a-Si:H) are reviewed with emphasis on the effects of deep levels (principally the D or dangling bond defect) on the electron drift mobility. An outline of several techniques for measuring drift mobilities is also given to establish their relationships to the transient drift-mobility function. µ(t). Three aspects of the electron µ(t) in undoped a-Si:H are described in detail: (i) anisotropy at long times, requiring a distinction between axial electric fields (parallel to the growth axis) and planar fields normal to it, (ii) the D center deep-trapping cutoff observed in the axial µ(t), and (iii) D center multiple-trapping at long times in the planar drift-mobility. Microstructure effects which might account for the electron drift-mobility are discussed.
Brownmillerite-perovskite intergrowths of the type m(A2B2O5)*n(ABO3), where m = 1 and n = 1, were investigated with respect to cation ordering. It was found that Sr31n2ZrO8, Sr31n2HfO8, Ba3Sc2TiO8 and Ba31n2TiO8 form in a disordered cubic structure, while Sr3Sc2ZrO8 and Ba3Sc2ZrO8 form an ordered cation arrangement. The Arrhenius plots of the oxygen ion conductivity of Ba3Sc2ZrO8, Sr31n2HfO8, and Ba31n2TiO8 contain discontinuities that appear to be caused by an oxygen vacancy order-disorder transition. High temperature powder-X ray diffraction did not show any evidence for cation ordering that might otherwise have created the changes in activation energy in the conductivity plots.
Microcrystalline silicon (μc-Si) films were prepared by electron cyclotron resonance assisted chemical vapor deposition (ECRCVD) using helium, argon and hydrogen dilution. The crystalline fraction was estimated from Raman backscattering spectra and scanning electron-microscopy (SEM) was used to obtain information on roughness and homogeneity of the films. For hydrogen dilution the highest crystallinity (Xc = 85 %) occurs at a ratio of ΔH = [H2]/([H2]+[SiH4])= 0.98. At the same time the deposition rate decreases continuously with increasing H2 dilution. These results are consistent with the idea that H etching promotes the growth of μc-Si. At ΔH > 0.98 a Xc decreases due to a H mediated transition of small crystallites into amorphous tissue. The implications of these results for the growth mechanisms are discussed.
We have used synchrotron x-ray diffraction to study the low-T homoepitaxial growth on Ag(001) and Cu(001) surfaces. For both systems, we found that a large, temperature-dependent vacancy concentration is incorporated in films grown below 160K. The vacancy trapping occurs concomitantly with substantial changes in the surface morphology, where a non-monotonic temperature dependence of the mean-square surface roughness has been previously observed. For Cu/Cu(001) we also found that the concentration of vacancies incorporated at 110K evolves, upon heating, according to the vacancy annealing behavior well-known from radiation damage studies of bulk copper and it is consistent with the activation energy for vacancy mobility.