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To assess resource allocation and costs associated with US hospitals preparing for the possible spread of the 2014–2015 Ebola virus disease (EVD) epidemic in the United States.
A survey was sent to a stratified national probability sample (n=750) of US general medical/surgical hospitals selected from the American Hospital Association (AHA) list of hospitals. The survey was also sent to all children’s general hospitals listed by the AHA (n=60). The survey assessed EVD preparation supply costs and overtime staff hours. The average national wage was multiplied by labor hours to calculate overtime labor costs. Additional information collected included challenges, benefits, and perceived value of EVD preparedness activities.
The average amount spent by hospitals on combined supply and overtime labor costs was $80,461 (n=133; 95% confidence interval [CI], $56,502–$104,419). Multivariate analysis indicated that small hospitals (mean, $76,167) spent more on staff overtime costs per 100 beds than large hospitals (mean, $15,737; P<.0001). The overall cost for acute-care hospitals in the United States to prepare for possible EVD cases was estimated to be $361,108,968. The leading challenge was difficulty obtaining supplies from vendors due to shortages (83%; 95% CI, 78%–88%) and the greatest benefit was improved knowledge about personal protective equipment (89%; 95% CI, 85%–93%).
The financial impact of EVD preparedness activities was substantial. Overtime cost in smaller hospitals was >3 times that in larger hospitals. Planning for emerging infectious disease identification, triage, and management should be conducted at regional and national levels in the United States to facilitate efficient and appropriate allocation of resources in acute-care facilities.
ABSTRACT. This article focuses on the positioning and development of English Atlantic ports in the 17th and 18th centuries by drawing up a changing cartography of the port network. The most important ports combined physical features, even of mediocre quality, such as quays and basins, with economic activity based on a large volume of production and exchange. But the value of a port was determined by the dynamism and organization of merchants and traders.
RÉSUMÉ. Cet article s'intéresse à la localisation et au développement des ports du monde atlantique anglais aux XVIIe et XVIIIe siècle en dressant une cartographie évolutive du réseau portuaire. En fait les ports les plus importants combinent des atouts naturels même médiocres, avec pour certains des équipements comme les quais et les bassins, avec une activité économique qui s'appuie sur un fort volume de production et d'échanges. Mais la valeur d'un port se juge aussi à la dynamique et à l'organisation des marchands et négociants.
During the seventeenth and eighteenth centuries a British Atlantic world took shape with the colonisation of North America and the West Indies. By 1775 the British Empire in the Americas covered 88,803 square miles and contained a population of 8.6 million. Each of the British American settlements was originally based around ports and harbours, which served as nodal points for a maritime economy. North American and West Indian ports were connected to British ports through shipping, trade, and the movement of people across the Atlantic. Underpinned by a mercantilist framework in the form of various Navigation Acts, through which goods were largely required to be traded within the British Empire, ports and their merchants in Britain and British America had a pivotal role in the expansion of seaborne commerce for both Britain and her colonies. Smaller ports provided shipping points for ships to enter, transfer cargoes and receive crew, payments and refreshment. Larger ports, with waterborne and overland connections linking up with productive hinterlands, served as powerhouses of an intricate web of trading connections across the Atlantic that connected productive areas for raw materials and agricultural resources with centres of consumer demand.
This paper reviews recent developments in the production and use of unconventional natural gas in the United States with a focus on water and greenhouse gas emission implications. If unconventional natural gas in the U.S. is produced responsibly, transported and distributed with little leakage, and incorporated into integrated energy systems that are designed for future resiliency, it could play a significant role in realizing a more sustainable energy future; however, the increased use of natural gas as a substitute for more carbon intensive fuels will alone not substantially alter world carbon dioxide concentration projections.
This paper reviews recent developments in the production and use of unconventional natural gas in the United States with a focus on environmental impacts. Specifically, we focus on water management and greenhouse gas emission implications. If unconventional natural gas in the United States is produced responsibly, transported and distributed with little leakage, and incorporated into integrated energy systems that are designed for future resiliency, it could play a significant role in realizing a more sustainable energy future. The cutting-edge of industry water management practices gives a picture of how this transition is unfolding, although much opportunity remains to minimize water use and related environmental impacts. The role of natural gas to mitigate climate forcing is less clear. While natural gas has low CO2 emissions upon direct use, methane leakage and long term climate effects lead to the conclusion that increased use of natural gas as a substitute for more carbon intensive fuels will not substantially alter world carbon dioxide concentration projections, and that other zero or low carbon energy sources will be needed to limit GHG concentrations. We conclude with some possible avenues for further work.
Objective: To examine the mental health effects of Hurricane Ike, the third costliest hurricane in US history, which devastated the upper Texas coast in September 2008.
Method: Structured telephone interviews assessing immediate effects of Hurricane Ike (damage, loss, displacement) and mental health diagnoses were administered via random digit-dial methods to a household probability sample of 255 Hurricane Ike–affected adults in Galveston and Chambers counties.
Results: Three-fourths of respondents evacuated the area because of Hurricane Ike and nearly 40% were displaced for at least one week. Postdisaster mental health prevalence estimates were 5.9% for posttraumatic stress disorder, 4.5% for major depressive episode, and 9.3% for generalized anxiety disorder. Bivariate analyses suggested that peritraumatic indicators of hurricane exposure severity—such as lack of adequate clean clothing, electricity, food, money, transportation, or water for at least one week—were most consistently associated with mental health problems.
Conclusions: The significant contribution of factors such as loss of housing, financial means, clothing, food, and water to the development and/or maintenance of negative mental health consequences highlights the importance of systemic postdisaster intervention resources targeted to meet basic needs in the postdisaster period.
(Disaster Med Public Health Preparedness. 2012;6:26–32)
This article considers the changing nature of remittance procedures in the eighteenth-century British slave trade. It explains why bills of exchange became the preferred form of making payment for slave sales, rather than specie or produce. It also indicates the legal and institutional practices that informed the circulation of bills of exchange in a notoriously risky form of long-distance trade. The growth and complexity of the British slave trade, which was conducted mainly by private merchants, led to procedures such as remitting bills “in the bottom” of ships that had supplied slaves to North American and Caribbean markets and the extension of lengthy credit periods to purchasers. Colonial factors played a role as well, acting as the agents for coordinating remittances, and secure British merchant houses were deployed as “guarantees” for payment by bills. The development of credit practices associated with the slave trade, including remittance procedures, helped to strengthen the British economy by providing sound, complex intermediary instruments for the realization of profits from international trade.
Large (15mm diameter) single-crystal AlN boules have been prepared using sublimationrecondensation growth. X-ray topography shows that the dislocation density averages less than 103 cm2 in some of the substrates but also that the dislocations are not uniformly distributed. Also, strain due to the differential expansion with the crucible walls seems to cause severe cracking in the periphery of the crystal and high-strain regions. Thermal analysis using the Scanning Thermal Microscopy (SThM) reveals a thermal conductivity of 3.4 ± 0.2 W/K-cm, which is the largest value ever reported for AlN.
Bulk aluminum nitride boules have been grown at driving rates of 0.9mm/h by the self-seeded sublimation-recondensation technique. Up to 15mm diameter substrates cut from those boules present large single crystal grains that have been analyzed using different techniques. X-ray double crystal diffraction shows a full-width-at-half-maximum of around 100 arcsec and X-ray topography reveals extensive areas with a density of dislocations less than 104 cm−2. These substrates have been prepared by chemical mechanical polishing techniques to obtain a surface roughness of 1.4-1.6nm.
Aluminum nitride (AlN) boules larger than 2 inches in diameter were grown by the sublimation-recondensation technique. X-ray Laue diffraction was used to characterize the crystallinity and orientation of the boules, and 2” dia. substrates were sliced with typical thickness of ∼500 μm. The wafers were then polished in order to meet the common standards for wafer thickness and flatness. The Al-terminated surface was finished with a proprietary chemical-mechanical process and showed RMS roughness of 0.5 nm or less as measured by atomic force microscopy (5×5 μm area). Currently, the substrates have some polycrystalline regions that are highly textured but about 85% of the total area is monocrystalline. The dislocation density in the crystalline regions of the substrate was measured by preferential chemical etching and then determining the resulting etch pit density (EPD). The etching technique involves potassium hydroxide and has been qualified through correlation with x-ray topography measurements of the dislocations. Measured EPD varied from 250 cm−2 to 3×104 cm−2. Other structural defects such as low angle grain boundaries, prismatic slip bands, inversion domains, have also been observed. The rare appearance of these defects will be discussed even though their role in the epitaxial growth of GaN and AlGaN is yet to be clarified.
Aluminum nitride (AlN) offers exceptional properties necessary to explore the development of large area substrates for nitride based electronics and photonics. Recent studies on AlN bulk growth using the sublimation-recondensation method developed at Crystal IS demonstrated high-quality crystals with low dislocation density and crystallographic uniformity. The diameter enlargement of these AlN boules is often associated with extensive defect generation. The goal of this study is to evaluate the origin and distribution of growth defects in AlN bulk crystals.
AlN crystals were grown using the sublimation-recondensation technique and then they were sliced into wafers. The defect evaluation in this study was performed using x-ray topography, differential image contrast and polarized-light optical microscopy, atomic force microscopy (AFM) and etch pit pattern delineation. Special attention was paid to crack development and propagation, grain boundary distribution, micro-scale inhomogenities as well as to the origin and density of dislocations. The major cause of growth defect appears to be non-linearity of both axial and radial temperature gradients. Growth optimization results in lower defect density and improved crystallinity of the AlN crystals.
One of the best–known f eatures of eighteenth–century British commercial history is the prominence of Liverpool as a slave–trading port. After the London–based Royal African Company's monopoly in the slave trade ended in 1698, Liverpudlians entered the ‘Guinea’ business slowly: they dispatched only two slaving vessels in the first decade of the eighteenth century when the slave trade had just become legally open to private merchants. The Mersey port's slave–trading activity rose significantly, however, after the end of the War of the Spanish Succession and continued to grow rapidly thereafter. Forty–two slave ships cleared out from Liverpool in the period 1721–30 and 197 between 1731 and 1740; these represented 6 per cent and 27 per cent respectively of the slave ships leaving Britain. Liverpool then overtook London and Bristol, the other two large British slave trading centres. Liverpool sent out 217 slaving ships in the period 1741–50 – 43 per cent of the vessels dispatched in the British slave trade. A continuous rise after the mid–1740s led Liverpool to a commanding position in the trade. Bristol and London, by contrast, had more fluctuating involvement in the slave trade in the second half of the eighteenth century.
In 1751–60 Liverpool dispatched ships on 500 slaving ventures, which gave her a 56 per cent share of ships embarked on slaving voyages from Britain. In 1761–70, 1771–80 and 1781–90 Liverpool dispatched 684, 608 and 579 slaving voyages, accounting respectively for shares of 54, 60 and 70 per cent of slaving ventures from Britain. Liverpool sent out 910 slave ships between 1791 and 1800 and 790 in the final years of the British slave trade from 1801 to 1807. In those two periods 77 and 79 per cent of the slaving voyages leaving Britain were from the Mersey. Liverpool probably invested around £200,000 in the slave trade in 1750 and more than £1 million in 1800. In 1807 Liverpool had an annual investment of £2,641,200 in the slave trade. It was dubbed ‘the metropolis of slavery’. Throughout the entire period of the British slave trade Liverpool ships delivered an estimated 1,171,171 slaves to the New World, making it the most important port of departure for transatlantic slaving voyages before the nineteenth century.
Grey matter and other structural brain abnormalities are consistently
reported in first-onset schizophrenia, but less is known about the extent
of neuroanatomical changes in first-onset affective psychosis
To determine which brain abnormalities are specific to (a) schizophrenia
and (b) affective psychosis
We obtained dual-echo (proton density/T2-weighted) magnetic resonance
images and carried out voxel-based analysis on the images of 73 patients
with first-episode psychosis (schizophrenia n=44,
affective psychosis n=29) and 58 healthy controls
Both patients with schizophrenia and patients with affective psychosis
had enlarged lateral and third ventricle volumes. Regional cortical grey
matter reductions (including bilateral anterior cingulate gyrus, left
insula and left fusiform gyrus) were evident in affective psychosis but
not in schizophrenia, although patients with schizophrenia displayed
decreased hippocampal grey matter and increased striatal grey matter at a
more liberal statistical threshold
Both schizophrenia and affective psychosis are associated with volumetric
abnormalities at the onset of frank psychosis, with some of these evident
in common brain areas
Nutrigenomics is the study of how constituents of the diet interact with genes, and their products, to alter phenotype and, conversely, how genes and their products metabolise these constituents into nutrients, antinutrients, and bioactive compounds. Results from molecular and genetic epidemiological studies indicate that dietary unbalance can alter gene–nutrient interactions in ways that increase the risk of developing chronic disease. The interplay of human genetic variation and environmental factors will make identifying causative genes and nutrients a formidable, but not intractable, challenge. We provide specific recommendations for how to best meet this challenge and discuss the need for new methodologies and the use of comprehensive analyses of nutrient–genotype interactions involving large and diverse populations. The objective of the present paper is to stimulate discourse and collaboration among nutrigenomic researchers and stakeholders, a process that will lead to an increase in global health and wellness by reducing health disparities in developed and developing countries.
cerebellar hypoplasia is a rare malformation caused by a variety of etiologies. it usually manifests clinically as non-progressive cerebellar ataxia with or without mental retardation. we further characterize a syndrome of autosomal recessive cerebellar hypoplasia in the hutterite population, referred to as dysequilibrium syndrome (des). we reviewed 12 patients (eight females, four males; age range 4 to 33y) with this syndrome. patients were examined and underwent a standard set of investigations to characterize better the clinical features, natural history, and neuroimaging of this syndrome. des is an autosomal recessive disorder with distinct clinical features including global developmental delay, late ambulation (after age 6y), truncal ataxia, and a static clinical course. neuroimaging is characterized by hypoplasia of the inferior portion of the cerebellar hemispheres and vermis, and mild simplification of cortical gyri.