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To identify ways that the built environment may support or disrupt safe doffing of personal protective equipment (PPE) in biocontainment units (BCU).
We observed interactions between healthcare workers (HCWs) and the built environment during 41 simulated PPE donning and doffing exercises.
The BCUs of 4 Ebola treatment facilities and 1 high-fidelity BCU mockup.
A total of 64 HCWs (41 doffing HCWs and 15 trained observers) participated in this study.
In each facility, we observed how the physical environment influences risky behaviors by the HCW. The environmental design impeded communication between trained observers (TOs) and HCWs because of limited window size or visual obstructions with louvers, which allowed unobserved errors. The size and configuration of the doffing area impacted HCW adherence to protocol, and lack of clear demarcation of zones resulted in HCWs inadvertently leaving the doffing area and stepping back into the contaminated areas. Lack of standard location for items resulted in equipment and supplies frequently shifting positions. Finally, different solutions for maintaining balance while removing shoe covers (ie, chair, hand grips, and step stool) had variable success. We identified the 5 key requirements that doffing areas must achieve to support safe doffing of PPE, and we developed a matrix of proposed design strategies that can be implemented to meet those requirements.
Simple, low-cost environmental design interventions can provide structure to support and improve HCW safety in BCUs. These interventions should be implemented in both current and future BCUs.
The functional composition of plant communities in montane regions has been studied for decades, and most recent analyses find that environmentally favourable landscapes at lower altitudes tend to be dominated by species with resource-acquisitive traits, while more resource-conservative taxa dominate higher-altitude communities. However, it is unclear the extent to which this pattern is driven by co-gradient variation within clades or changes in clade representation across the gradient. To test for co-gradient variation, species composition, phylogenetic structure and functional traits were quantified for 97 species within the plant family Melastomataceae at five locations across a 2500-m altitudinal gradient along Volcán Barva in Costa Rica. Average melastome leaf force to punch, specific leaf area and leaf size vary with altitude, while four other functional traits do not. Taxonomic dissimilarity between communities was correlated with altitudinal difference, while phylogenetic dissimilarity was correlated with altitudinal dissimilarity only when measured with a metric that emphasizes shallow turnover of the tips of the phylogeny. These results highlight how species turnover may be more pronounced than functional or phylogenetic variation along altitudinal gradients. In addition, these results highlight the conservation value of lowland tropical forests, which here harbour a disproportionate amount of phylogenetic and functional diversity.
We compared rotavirus detection patterns before (2001–2006) and after (2008–2015) rotavirus vaccine introduction. We also compared rotavirus detection patterns in odd (2009, 2011, 2013, 2015) and even (2008, 2010, 2012, 2014) years post-vaccine separately. Results of stool rotavirus antigen testing from inpatient, outpatient and emergency department encounters from July 2000 to July 2015 at two paediatric hospital laboratories in Atlanta, Georgia were reviewed. Post-vaccine, rotavirus detection declined (30.2% vs. 13.7% (overall 54.6% decline, P <0.001)), occurred more frequently outside the rotavirus season (19.8% vs. 3.5%; P < 0.001), and was more common among older children (26 vs. 13 median months of age; P < 0.001). During odd years post-vaccine, rotavirus detection was significantly higher than even years (20.2% vs. 6.4%; P < 0.001). Rotavirus detection declined substantially and developed a biennial pattern in the post-vaccine era. The intensity and temporality of rotavirus detection in odd years post-vaccine resembled that observed pre-vaccine, although considerably reduced in magnitude.
A number of laser facilities coming online all over the world promise the capability of high-power laser experiments with shot repetition rates between 1 and 10 Hz. Target availability and technical issues related to the interaction environment could become a bottleneck for the exploitation of such facilities. In this paper, we report on target needs for three different classes of experiments: dynamic compression physics, electron transport and isochoric heating, and laser-driven particle and radiation sources. We also review some of the most challenging issues in target fabrication and high repetition rate operation. Finally, we discuss current target supply strategies and future perspectives to establish a sustainable target provision infrastructure for advanced laser facilities.
From U, B, V photometry of 104 stars in a field of radius ~ 30′ centered on the X-ray binary star Cyg X-1 (HDE 226868), we have studied the color excess E(B–V) as a function of distance. Spectral types were observed de novo for 42 of these stars. We conclude that HDE 226868 cannot be nearer than 1 kpc, and is probably at a distance of 2.5 kpc or more. The primary component is therefore a luminous OB star of mass ~30 M⊙, and the X-ray component has a minimum mass ~6 M⊙.
Centaurus A (NGC 5128) is a giant early-type galaxy containing the nearest radio-bright AGN. The high-angular resolution Chandra images of Cen A reveal multi-scale X-ray structures with unprecedented detail and clarity. We present results from our study of X-ray structures surrounding the Cen A nuclear region, including the discovery of giant arc-like structures, extending to about 8 kpc in the direction perpendicular to the jet. We compare the X-ray structures with observations in other wavelengths and discuss their implication for a global understanding of the morphology of Cen A.
We discuss two themes from Chandra cluster observations. First, we describe the interaction of buoyant, radio emitting plasma bubbles with the hot intracluster gas. Second we summarize the Chandra observations of “cold” fronts (sharp discontinuities in gas density and temperature) separating cool, denser gas clouds from the hotter intracluster medium.
To describe current Ebola treatment center (ETC) locations, their capacity to care for Ebola virus disease patients, and infection control infrastructure features.
A 19-question survey was distributed electronically in April 2015. Responses were collected via email by June 2015 and analyzed in an electronic spreadsheet.
The survey was sent to and completed by site representatives of each ETC.
The survey was sent to all 55 ETCs; 47 (85%) responded.
Of the 47 responding ETCs, there are 84 isolation beds available for adults and 91 for children; of these pediatric beds, 35 (38%) are in children’s hospitals. In total, the simultaneous capacity of the 47 reporting ETCs is 121 beds. On the basis of the current US census, there are 0.38 beds per million population. Most ETCs have negative pressure isolation rooms, anterooms, and a process for category A waste sterilization, although only 11 facilities (23%) have the capability to sterilize infectious waste on site.
Facilities developed ETCs on the basis of Centers for Disease Control and Prevention guidance, but specific capabilities are not mandated at this present time. Owing to the complex and costly nature of Ebola virus disease treatment and variability in capabilities from facility to facility, in conjunction with the lack of regulations, nationwide capacity in specialized facilities is limited. Further assessments should determine whether ETCs can adapt to safely manage other highly infectious disease threats.
Infect. Control Hosp. Epidemiol. 2016;37(3):313–318
The process of East Asian regionalism received a shot in the arm in 2008 with the proposal made by Australian Prime Minister Kevin Rudd about restructuring the Asia-Pacific regional architecture. This was followed by the proposal made by Japanese Prime Minister Yukio Hatoyama on an East Asian community. There are substantive differences between the two concepts (one being that the former has been much more developed over time while the latter has been left for further discussion). Both, however, have attracted quite a bit of attention, not primarily because of their substantive content but more because of their implications for how currently existing regional institutions seem to be falling short of expectation thus creating the need to explore alternative arrangements. In an indirect way, this is reflective of how much its partners are beginning to grow weary of the ASEAN Way and of the way ASEAN has driven the process.
The very success, however, of ASEAN in managing intra-ASEAN relations to the point of being able to make the prospect of conflict between ASEAN member states unlikely (as well as its involvement in the Cambodian conflict) gave it an international stature out of proportion to the status of its individual member states. This was in fact recognized by its dialogue partners when they accepted the idea that the Association should chair the post-Cold War forum that would oversee discussions and dialogue on the security of the Asia-Pacific region. The fact that it was also called the ASEAN Regional Forum (ARF) when it was established in 1994 more than stamped the ASEAN mark upon it — it signified the adoption of ASEAN norms (especially the consensus-based method of decision-making) as the foundation for what was effectively a nascent attempt at extra-ASEAN regionalism. That it did so with much misgiving did not detract from its determination to show the applicability of the ASEAN “model” to a wider Asia-Pacific scope. This started ASEAN on its way to a significant shift in the evolution of its identity — from an association dedicated to keeping the Southeast Asian region free from being enmeshed in great power rivalries to one which accepted its “centrality” in a wider East Asian and Asia-Pacific regionalism, a process that would entail accepting the involvement of and engaging the major powers in the context of the region.
The spectrum of the supergiant FG Sge has been studied from a series of high dispersion 120-in. coudé spectrograms obtained during the interval 1969–72, thus continuing the work of Herbig and Boyarchuk (1968). The star, of effective temperature about 6500 K in 1972, is cooling at the rate of 250 K yr-1; it is known to have ejected a still visible planetary nebula some 6000 years ago (Flannery and Herbig, 1973). Abnormally strong absorption lines of Y ii, Zr ii, Ce ii, La iiand other s-process species began to appear in the spectrum of the central star some time after 1967 and have progressively strengthened. Present abundances per gram of these elements are about 25 times the solar value. There is little doubt that the atmosphere of the star has been enriched in these elements during the past seven years, but the rate of enrichment now appears to be slowing down.
At the crossroad between nutrient supply and requirements, the liver plays a central role in partitioning nitrogenous nutrients among tissues. The present review examines the utilisation of amino acids (AA) within the liver in various physiopathological states in mammals and how the fates of AA are regulated. AA uptake by the liver is generally driven by the net portal appearance of AA. This coordination is lost when demands by peripheral tissues is important (rapid growth or lactation), or when certain metabolic pathways within the liver become a priority (synthesis of acute-phase proteins). Data obtained in various species have shown that oxidation of AA and export protein synthesis usually responds to nutrient supply. Gluconeogenesis from AA is less dependent on hepatic delivery and the nature of nutrients supplied, and hormones like insulin are involved in the regulatory processes. Gluconeogenesis is regulated by nutritional factors very differently between mammals (glucose absorbed from the diet is important in single-stomached animals, while in carnivores, glucose from endogenous origin is key). The underlying mechanisms explaining how the liver adapts its AA utilisation to the body requirements are complex. The highly adaptable hepatic metabolism must be capable to deal with the various nutritional/physiological challenges that mammals have to face to maintain homeostasis. Whereas the liver responds generally to nutritional parameters in various physiological states occurring throughout life, other complex signalling pathways at systemic and tissue level (hormones, cytokines, nutrients, etc.) are involved additionally in specific physiological/nutritional states to prioritise certain metabolic pathways (pathological states or when nutritional requirements are uncovered).
In this study we present investigation on the anelastic behavior of sputtered 1 [.proportional]m thin Cu films. Most of the literature that reports on the mechanical properties of thin metallic films is based on substrate curvature measurements. We have developed a new version of a bulge tester that combines the capacitive measurement of the bulge deflection of a membrane with a resonance frequency measurement of the residual stress in the membrane. A Cu membrane is plastically deformed to a pre-determined strain by controlled gas-pressure bulging of the membrane. After the bulging stress is removed, the residual tensile stress, which has been decreased by the plastic deformation, is then determined by measuring the resonant frequency as a function of time. Immediately after plastic straining, the residual (tensile) stress of membranes was observed to increase. At room temperature a maximum stress was typically reached in the order of an hour. At still longer times the stress decreased again as a result of creep. The transient increase in stress following plastic straining grew larger as the amount of plastic strain produced by bulging was increased. With higher temperatures the transient became both faster and larger. A model is presented that based on the mechanism of thermally activated glide separates the microstructure in a class of “soft” and “hard” grains solving the issue of an “apparent” increase in strain energy as a function of time after deformation.
A key process in our approach to monolithic three-dimensional (3D) integration is the bonding of 200-mm wafers using dielectric polymer thin films as bonding glues. After discussing the desired properties of polymer thin films, we describe how bonding protocols are evaluated using silicon and glass wafers. After bonding, the fraction of bonded area was inspected optically and a razor blade method was used to indicate bonding strength. Thermal stability and bonding integrity were evaluated using thermal cycling and backside grinding and polishing. To date, we have studied benzocyclobutene (BCB), Flare™, and methylsilsesquioxane (MSSQ) and Parylene-N as bonding glues. Wafer pairs bonded using BCB showed a larger fraction of bonded area, and those using Flare indicated higher thermal stability. Both BCB and Flare glues provided good bonding integrity after backside grinding tests. Changes in the chemical structures of BCB and Flare glue during bonding were analyzed using FTIR in order to understand the bonding mechanism and to improve the bonding process.
A brief review is given of models which propose a correlation between electromigration resistance and the mechanical strength of thin film interconnects. In an attempt to achieve metallurgical strengthening and improved electromigration resistance, aluminum films were implanted with oxygen ions. Preliminary electromigration tests on line arrays patterned from these films resulted in lifetimes comparable to the standard Al films. The lack of improvement is attributed to enhanced hillock/whisker growth during electromigration in the implanted interconnects. This behavior is coincident with a lower compressive strength in similarly treated continuous films at elevated temperatures as measured by the substrate curvature technique.
Accelerated electromigation tests on unpassivated, pure aluminum interconnects were performed. The failure mechanisms were observed by interrupting the tests and exanming the conductor lines using an SEM. Because the metal thin film was subjected to a so-called laser reflow process before patterning, grain boundaries were visible in the SEM as thermal grooves. Voids were observed to move along the line and to grow in a transgranular manner, and a characteristic asymmetric void shape was identified which seems to be related to the failure mechanism. It is argued that substantial progress in modelling and understanding of electromigration failure can be made by consideration of such void shape effects.
Accelerated electromigation tests on unpassivated, pure aluminum interconnects were performed. The failure mechanisms were observed by interrupting the tests and examining the conductor lines using an SEM. Because the metal thin film was subjected to a so-called laser reflow process before patterning, grain boundaries were visible in the SEM as thermal grooves. Voids were observed to move along the line and to grow in a transgranular manner, and a characteristic asymmetric void shape was identified which seems to be related to the failure mechanism. It is argued that substantial progress in modelling and understanding of electromigration failure can be made by consideration of such void shape effects.