cssi/SciSciGPT-SciSciNet huggingface dataset:
Photoelectrochemical investigation of ultrathin film iron oxide solar cells prepared by atomic layer deposition.

Atomic layer deposition was used to grow conformal thin films of hematite with controlled thickness on transparent conductive oxide substrates. The hematite films were incorporated as photoelectrodes in regenerative photoelectrochemical cells employing an aqueous [Fe(CN)6]3-/4- electrolyte. Steady state current density versus applied potential measurements under monochromatic and simulated solar illumination were used to probe the photoelectrochemical properties of the hematite electrodes as a function of film thickness. Combining the photoelectrochemical results with careful optical measurements allowed us to determine an optimal thickness for a hematite electrode of ∼20 nm. Mott−Schottky analysis of differential capacitance measurements indicated a depletion region of ∼17 nm. Thus, only charge carriers generated in the depletion region were found to contribute to the photocurrent.
Production of p--n junctions with bulk controlled characteristics

Two methods of eliminating surface effects so that microplasma breakdown of p–n junctions can be observed are described, and their limitations are discussed. The first, applicable to diffused junctions, increases the space-charge-layer width, while the second reduces the applied voltage at the periphery of alloyed structures.
An anatomic and functional classification for the diagnosis and treatment of inguinal hernia

A simple classification of inguinal hernias is presented which can be valuable to surgeons as a (1) blueprint for dissecting the canal, (2) means for choosing the most appropriate operative procedure, (3) means for evaluating and correlating the prognosis of postoperative symptoms, time of convalescence, and degree of disability, and (4) method of identifying and communicating the exact anatomic derangement found so that accurate and consistent follow-up studies and statistics can be prepared. Diligent follow-up is essential for verifying the true results of hernia surgery techniques. Such follow-up requires that the surgeon be dedicated to examining his patients for many years, as well as to understanding, recording, and referencing the exact anatomic and functional defects found and the repairs used to correct them. Only with these factors identified and recorded can there be a basis for meaningful reporting and valuable conclusions. The classification of inguinal hernias presented here is intended to provide surgeons an opportunity to better evaluate their own methods and to more clearly communicate results with colleagues. As Oliver Wendell Holmes once said, "Many times ideas grow better when they are transplanted from one mind to another."
Composition and stability of salts on the surface of Europa and their oceanic origin

We present theoretical models of the composition, the relative abundances, and the stability of hydrated salts on the surface and in the icy shell of Jupiter's satellite Europa and discuss whether those salts have an oceanic origin. The evaluations were done with thermodynamic calculations of (1) salt dehydration equilibria at the conditions of the surface of Europa and its icy shell, (2) chemical equilibria involving solids and water vapor in the Na-K-Mg-Ca-S-Cl-H2O system at surface temperatures and variable partial pressures of water vapor, and (3) changes in aquatic chemistry and sequences of salt precipitation from freezing oceanic water, using cosmochemical, mass balance, and physical-chemical constraints on the elemental and ionic composition of the ocean. Mass balance calculations of total or partial extraction of elements into an ocean from a carbonaceous chondrite type mantle show that magnesium and sulfate rather than chloride and sodium could be the most abundant solutes in the ocean. Freezing oceanic water of this composition leads to brines that differ in composition from the original water and to deposition of ice and highly hydrated sulfates of Mg, Na, and Ca as well as alkali chlorides. After freezing is complete, highly hydrated salts remain stable in ice-bearing surface materials and throughout the icy shell. For hypothetical surface salt lag deposits, formed through sublimation/sputtering of ice and dehydration of salts, we predict hydration stratification with depth, approaching the highest hydration states in ice-bearing materials in the lowest parts of the deposits. We discuss the effects of fast disequilibrium freezing and variable dehydration rates of salts on the predicted mineral assemblages at the surface. All of our models, which are independent of observations, predict the predominance of Mg and Na sulfates in surface salts, in agreement with spectroscopic models for the nonicy surface material in the near infrared spectral region.
Military pollution and natural purity: seeing nature and knowing contamination in Vieques, Puerto Rico

Military activities have produced contaminated environments at many sites around the world. This contamination and the associated health risks play a large role in how these places can be redeveloped after military use. In this essay we focus on the island of Vieques, Puerto Rico which was used as a bombing range by the US military for six decades until 2003. We examine the ways different groups of people perceive this formerly militarized landscape and the ways that these perceptions legitimatize certain redevelopment options over others. Through participant observation, semi-structured interviews and an analysis of textual materials we found that many local residents view the island as suffering from severe contamination while the large number of visitors, tourism promoters and North Americans now flocking to the post-militarized Vieques view it quite differently. These perceptions of purity and contamination, affected by different knowledges of the island’s history, have led to differing valuation of the landscape and contentious economic, political, and cultural battles over an island often labeled “natural” despite a history of military use and social exclusion.
Chemical kinetics of the high pressure oxidation of n-butane and its relation to engine knock☆

A chemical kinetic oxidation mechanism for n-butane is employed to study hydrocarbon autoignition related to engine knock. A low temperature submechanism has been added to a previously developed high temperature mechanism in order to examine the importance of low temperature reaction paths in autoignition. Numerical calculations follow reactions taking place in a sample of end gas and are used to identify the controlling chemical reactions that can lead to autoignition. Reactions that involve the production and consumption of HO/sub 2/ and H/sub 2/O/sub 2/ were found to play a crucial role in high pressure autoignition. A possible role of selected antiknock additives was investigated numerically, with calculations showing that the removal of HO/sub 2/ and H/sub 2/O/sub 2/ by these additives would provide a strong inhibiting effect on the autoignition process.
A LINE-OF-SIGHT GALAXY CLUSTER COLLISION: SIMULATED X-RAY OBSERVATIONS

Several lines of evidence have suggested that the the galaxy cluster Cl 0024+17, an apparently relaxed system, is actually a collision of two clusters, the interaction occurring along our line of sight. In this paper we present a high-resolution N-body/hydrodynamics simulation of such a collision. We have created mock X-ray observations of our simulated system using MARX, a program that simulates the on-orbit performance of the Chandra X-ray Observatory. We analyze these simulated data to generate radial profiles of the surface brightness and temperature. At later times, t = 2.0 3.0 Gyr after the collision, the simulated surface brightness profiles are better fit by a superposition of two β-model profiles than a single profile, in agreement with the observations of Cl 0024+17. In general, due to projection effects, much of the post-collision density and temperature structure of the clusters is not seen in the observations. In particular, the observed temperatures from spectral fitting are much lower than the temperature of the hottest gas. We determine from our fitted profiles that if the system is modeled as a single cluster, the hydrostatic mass estimate is a factor �2-3 less than the actual mass, but if the system is modeled as two galaxy clusters in superposition, a hydrostatic mass estimation can be made which is accurate to within �10%. We examine some implications of these results for galaxy cluster X-ray surveys. Subject headings: galaxies: clusters: general — galaxies: clusters: individual (Cl 0024+17)— methods: N-body simulations — X-rays: galaxies: clusters
Cardiac arrest-induced global cerebral ischemia studied in vitro.

Abstract The goal of the present study was to characterize the effects of chest compression-induced global cerebral ischemia on the hippocampal slice preparation. One of the characteristics of rats exposed to such cardiac arrest is a high susceptibility to sound-induced seizures. We tested audiogenic seizures as an in vivo indicator of ischemic cerebral damage and as a possible small animal model of epilepsy. The results of these tests were reported eleswhere. Long-Evans male rats (200–350 g) were subjected to 7 min of chest compression sufficient to stop the pumping action of the heart. The rats were then revived using cardiopulmonary resuscitation. Evaluation of cerebral damage following cardiac arrest and resuscitation was performed in vitro , by testing neuronal responses to electrical stimulation in hippocampal slices prepared from these animals. Sham control animals were used for comparisons. Twenty-one to 146 days after rats were chest-compressed, hippocampal slices were prepared. Sham control rats, anesthetized but not chest-compressed, were sacrificed one week later for preparation of slices. Rats in a second group exposed to 7-min chest compression, were sacrificed at different time intervals after their resuscitation (from l h to 7 days); hippocampal slices were prepared for electrophysiological analysis of neuronal damage. The results of these studies indicate that 3 weeks or longer after chest compression the evoked CA1 population spike amplitude in hippocampal slices was significantly attenuated; in 60% of these slices an epileptiform response was evoked. An increased proportion of slices prepared from rats 1 to 48 h after chest compression showed an augmentation in the amplitude of the evoked population spike; 72 h and up to 7 days after chest compression, an attenuation in the evoked CA1 population spike amplitude was observed, signaling delayed neuronal damage.
Estimating the range of Baleen whale calls recorded by hydrophone streamers during seismic surveys

Like all sources of anthropogenic sound in the oceans, seismic surveys have the potential to disturb marine mammals and impede their communications. Since airgun arrays produce a considerable amount of low frequency energy, their impact on Baleen whales may be most significant. For these reasons, extensive mitigation efforts accompany seismic surveys, including visual and acoustic monitoring, but additional approaches could be useful to verify these efforts and study the behavior of whales. One approach is to utilize the hydrophone streamer to detect and locate calling Baleen whales. To develop this method, data are being analyzed from a seismic reflection survey conducted with the R/V Langseth off the coast of Washington in summer 2012. The seismic streamer is 8 km long with 636 hydrophones sampled nearly continuously at 500 Hz. The work focuses on time intervals when only a mitigation gun is firing because of marine animal sightings or turns at the ends of lines. Ranges and orientations are estimated by calculating the signal arrival angles for different groups of receivers. Data from the marine mammal observers on the R/V Langseth and other ships in the area are used to verify the analysis. [Sponsored by NSF.]
On the rôle of tube walls, and surface and space charges in electrical discharges through rarefied gases

Abstract Several matters pertaining to the part played by tube walls, and surface and space charges in electrical discharges through rarefied gases, are briefly discussed, and experiments are described which throw light on some of the processes involved in such discharges. Measurements made under identical conditions of the falls of potential between striae in the positive columns of discharges in hydrogen at various pressures in two glass tubes of different diameters showed that for pressures above 1.1 mm. these falls were increasingly greater in the larger tube. The results of experiments done with discharges produced under unusual conditions and bearing on the radial and axial fields present in the positive columns of discharges are described, and photographs of some of the discharges are reproduced in a part of which the positive column was made to pass through a long metal tube placed inside of the glass discharge tube, the two ends of the metal tube being at times both open and at other times both closed with wire gauzes of fine mesh. The potential assumed by the metal tube and the current flowing through its walls were measured, and special experiments were done to elucidate the process by which the current manages to penetrate the more or less field-free space inside the metal cylinder. The distributions of the space and surface charges along the length of a glass discharge tube were measured separately, at least roughly, and the nature of these distributions was found to depend markedly upon whether the anode or the cathode of the discharge tube was connected to earth, although the combined effects of the two charges of necessity produced the same field distribution within the discharge tube in both cases. The gases used in the experiments were air and hydrogen.
Conceptual Model of CKD: Applications and Implications

The conceptual model of chronic kidney disease (CKD) was developed by the National Kidney Foundation's Kidney Disease Quality Outcome Initiative (NKF-KDOQI) in 2002 and subsequently revised and adopted by an international consensus under the auspices of KDIGO (Kidney Disease: Improving Global Outcomes) in 2005. This model includes concepts of definition, staging, outcomes, and treatment, as well as risk factors for the development, progression, and complications of CKD. Treatments are available for patients with risk factors and for each stage of CKD; these include slowing the progression of kidney disease, preventing and treating the complications of decreased glomerular filtration rate, and reducing cardiovascular disease risk factors and treating cardiovascular disease. In principle, measures to improve the prevention, detection, and treatment could reduce adverse outcomes, improve the quality of life, and prolong the survival of individuals with CKD. The conceptual model for CKD is now being applied to a public health approach for the prevention of the development, progression, and complications of CKD. Primary prevention is defined as prevention of CKD; secondary and tertiary prevention are defined as improving outcomes of patients with CKD stages 1 to 4 and kidney failure (CKD stage 5), respectively. The conceptual model has also fostered debate about important questions: Is CKD a disease or a cardiovascular disease risk-factor condition? Do all patients with CKD need to be referred to a nephrologist? What does CKD care include? Should the classification be modified to include cause of disease and prognosis? Can CKD evolve from acute kidney disease, and is CKD reversible? Is albuminuria a manifestation of a kidney disease or systemic endothelial dysfunction? Is the age-related decrease in glomerular filtration rate normal or abnormal, and should we change the definition of CKD in the elderly? A combination of immediate action, data gathering, and research to establish the efficacy, effectiveness, and costs related to CKD are needed to respond to CKD as a public health problem.
The prevalence and clinical impact of fibromyalgia in systemic lupus erythematosus

Objective. To ascertain the prevalence of fibromyalgia syndrome (FMS) in systemic lupus erythematosus (SLE) and to evaluate its clinical impact and relationship to SLE disease activity. Methods. A cross-sectional analysis of 102 patients from a public hospital SLE clinic. Information was obtained on symptoms of FMS, disability, tender points, pain thresholds, and SLE disease activity. Results. Twenty-two SLE patients (22%) met the American College of Rheumatology criteria for FMS, and another 24 (23%) had clinical FMS but did not meet the classification criteria. The patients who met the criteria for FMS had a significantly increased frequency and severity of symptoms commonly associated with FMS, and were much more likely to be unable to perform daily activities. The FMS patients also were less likely to be employed, and more likely to be divorced and to be receiving welfare or medical disability benefits. However, patients with and those without FMS did not differ in measures of SLE activity. Conclusion. FMS is very common in SLE patients, and accounts for many of the symptoms and much of the disability in these patients.
Interventions to reduce work-related musculoskeletal disorders

Work-related Musculoskeletal Disorders (WMSDs) continue to present a major challenge to workers and their employers in virtually every industry sector. Many disciplines have been involved in providing advice and working on interventions to prevent WMSDs or reduce their consequences. Since the early 1990s, 15 systematic reviews (excluding specific treatment modalities) have appeared in the peer-reviewed literature addressing musculoskeletal disorder reduction. The National Research Council-Institute of Medicine summarized many of these efforts in 2001. Using a systematic literature search strategy, we identified 20 randomized controlled studies, 17 quasi-experimental studies with control groups, and 36 paper reporting case studies with in the peer-reviewed literature between 1999-2003. Evidence is continuing to build that demonstrates combinations of measures appear to have the greatest effect in reducing WMSDs, although individual engineering and administrative controls can also have positive effects.
Incomplete redistribution in delayed thallium-201 single photon emission computed tomographic (SPECT) images: An overestimation of myocardial scarring

Abstract To determine if incomplete redistribution at 4 h in exercise tomographic thallium-201 studies is always due to a myocardial scar, 141 patients were evaluated before and after a total of 160 successful percutaneous transluminal coronary angioplasty procedures. Thallium studies were analyzed using polar “bull's-eye” maps. For both immediate and delayed images, abnormalities were quantified as a thallium score by calculating a standard deviation-weighted sum of pixels > 2.5 SD below gender-matched normal limits. One hundred forty-four of 160 studies indicated abnormalities before angioplasty. Of these 144, incomplete redistribution occurred in 111 (77%): 16 (14%) in patients with and 95 (86%) in patients without prior Q wave myocardial infarction. After angioplasty, improvement in delayed image score occurred in 8 (50%) of 16 patients with prior infarction and 72 (76%) of 95 patients without prior infarction (p To determine if additional delayed images could help differentiate scar from ischemia, an 8 to 24 h delayed image was obtained in each of 40 other patients with incomplete redistribution at 4 h. Of 28 patients with prior infarction, 15 had no redistribution and 13 had further redistribution at 8 to 24 h. Of 12 patients without prior infarction, 1 had no redistribution, 7 had further redistribution and 4 had complete redistribution. Thus, 4 h delayed thallium image defects frequently do not signify myocardial infarction. Their severity is proportional to immediate poststress abnormalities. Additional imaging at 8 to 24 h is recommended in patients with incomplete redistribution and no evidence of prior infarction.
Response of the lower Chesapeake Bay to forcing from Hurricane Floyd

Abstract Water density and velocity data from a ∼70-day period deployment across the entrance to the Chesapeake Bay were used in conjunction with wind velocity and sea level records to describe the response of the lower part of the estuary to forcing from Hurricane Floyd in mid-September 1999. Forcing associated with Floyd consisted of northeasterly winds during the 4 days prior to the passage of the storm eye over the lower Chesapeake Bay with hourly values that peaked at ∼21 m/s. After the passage of the eye of the storm on 16 September, winds shifted rapidly to northwesterly and peaked at 27 m/s. Buoyancy forcing from Floyd consisted of at least 2000 m3/s of direct freshwater input to the lower Chesapeake Bay. This was added to the runoff from the surrounding land that was already saturated with precipitation from tropical storm Dennis that affected the area of the lower bay in early September 1999. Northeasterly winds prior to the eye passage over the lower bay caused net inflow over the shallow northern half of the bay entrance and outflow in the deep channel to the south of the entrance. This outflow veered clockwise with depth. The change to northwesterly winds coincided with a pulse of freshwater that caused a salinity drop throughout the water column of up to 8 units in 1 day. Wind and river discharge set up a seaward barotropic pressure gradient force that drove net outflow everywhere across the entrance to the bay thus hindering any inflow and effectively flushing water out. The barotropic pressure gradient must have overcome the tendency of the baroclinic pressure gradient, related to the buoyancy input, to drive salty water into the estuary. It is estimated that approximately one-third of the net outflow was caused by wind forcing and two-thirds by freshwater discharge.
Modelling hysterisis phenomena in systems of multiple slits: Application of the principle of a minimum rate of entropy production at steady state

In recent publications (Kan and Greenfield, 1975, Levec, 1986, and Christensen, 1986), an experimentally observed phenomena of pressure drop hysterisis in two phase, cocurrent downflow of gas and liquid in packed beds has been reported. Until now, the phenomena is only qualitatively explained as an receding contact angle phenomena and no fundamental model has been developed which could predict the hysterisis. In this paper, a model is proposed which predicts the gas-liquid distribution in systems of multiple slits. The basis for the model is the principle of a minimum rate of entropy production at steady state and the model does predict a hysterisis in pressure drop and liquid saturation. Extension of the model to packed beds is not a trivial matter and work is currently underway on this problem.
Progressive inflammation and wasting in patients with ESRD

Body mass and, more importantly, body cell mass decline in patients with increasing time on RRT ([1][1]–[3][2]). Malnutrition, defined by low levels of albumin, low levels of prealbumin, low body mass index, and reduced physical function, is predictive of mortality ([4][3]). Although albumin
A refined model for thermoelastic analysis of initially curved and twisted composite beams

This paper deals with steady state thermoelastic problems in beam structures using the variational asymptotic method. First, we simplify the original three-dimensional heat conduction problem into a two-dimensional thermal cross-sectional analysis along with an optional one-dimensional heat conduction analysis. The reflnements up to the second order of the initial curvatures and twist are captured in the model. Having obtained the temperature fleld, we then construct a generalized Timoshenko model for the oneway coupled thermoelastic analysis. Several examples will be used to demonstrate the application and performance of the present model. The results will be compared with three-dimensional thermoelastic analysis using ANSYS.
Matching bent crystals to high-brilliance sources

Bent crystals are well suited to high-brilliance sources and add flexibility to the design of synchrotron radiation (SR) monochromators. A double crystal monochromator for high resolution in elastic scattering of SR is examined by methods developed for neutron optics. Computations with a neutron code adapted to the case of SR show that bending the first crystal can improve performance by strongly reducing the beam size at marginal gain in full beam intensity.
MAS5, a yeast homolog of DnaJ involved in mitochondrial protein import.

Abstract The nuclear mas5 mutation causes temperature-sensitive growth and defects in mitochondrial protein import at the nonpermissive temperature in the yeast Saccharomyces cerevisiae. The MAS5 gene was isolated by complementation of the mutant phenotypes, and integrative transformation demonstrated that the complementing fragment encoded the authentic MAS5 gene. The deduced protein sequence of the cloned gene revealed a polypeptide of 410 amino acids which is homologous to Escherichia coli DnaJ and the yeast DnaJ log SCJ1. Northern (RNA blot) analysis revealed that MAS5 is a heat shock gene whose expression increases moderately at elevated temperatures. Cells with a deletion mutation in MAS5 grew slowly at 23 degrees C and were inviable at 37 degrees C, demonstrating that MAS5 is essential for growth at increased temperatures. The deletion mutant also displayed a modest import defect at 23 degrees C and a substantial import defect at 37 degrees C. These results indicate a role for a DnaJ cognate protein in mitochondrial protein import.
Hectorite Complexes with Cu(II) and Fe(II)-1,10-Phenanthroline Chelates*

Characteristics and properties of complexes of a smectite (hectorite) with 1,10-phenanthroline (phen) chelates with iron or copper were determined by a variety of physical and chemical measurements. The complex ions showed high selectivity for the hectorite surface. Basal spacings of 17.4 A were produced by Fe(II) or Cu(II) analogues of M(phen) 3 2+ hectorite. Adsorption of gases and vapors by the M(phen) 3 2+ hectorite complex revealed large surface areas and reflected intrinsic characteristics of the complex ions. Lower surface areas were found for copper phen hectorite than iron phen hectorite probably because of the loss of a ligand from the Cu(II) ion. ESR spectra confirmed that appreciable Cu(II) existed as the bis-phen complex under certain conditions. An increase in the oxidation potential of the Fe(phen) 3 2+ -Fe(phen) 3 3+ couple above that in pure solvent was noted when these complexes were supported by the mineral surface.
Changing Practice: Impact of a National Institute on Foreign Language Teacher Preparation for the K‐6 Level of Instruction

: The almost 10% increase in elementary school foreign language programs in the United States in the past 10 years has resulted in a serious shortage of professionally prepared teachers for these programs. This study investigates the impact of a national institute on effecting change in the number of colleges and universities that prepare elementary school foreign language teachers. The institute provides professional preparation in early language education to teacher educators throughout the nation. Results of survey instruments and telephone interviews with the teacher educator participants indicate that the number of sites that prepare teachers for the early level of instruction did increase and that the institute resulted in many additional positive benefits. The profession is encouraged to work together to address the foreign language teacher shortage at the elementary school level to avoid repeating the crisis of the 1950s and 1960s.
Contribution of Arachidonic Acid Metabolites Derived Via Cytochrome P4504A to Angiotensin II-Induced Neointimal Growth

Angiotensin II and the arachidonic acid metabolite derived via cytochrome P450 20-hydroxyeicostetraenoic acid promote vasoconstriction and vascular smooth muscle cell (VSMC) proliferation. This study was conducted to determine if 20-hydroxyeicostetraenoic acid contributes to angiotensin II-induced neointimal formation in balloon-injured rat carotid artery. In anesthetized rats, the drugs were infused into the clamped segment of the injured right common carotid artery for 60 minutes. The drug solution and catheter were withdrawn, the common carotid artery was ligated, and blood flow was restored. Exposure of the injured artery to angiotensin II (200 nmol/L) or arachidonic acid (10 μmol/L) increased neointimal thickening at day 14 (intima/media ratio 0.71±0.14 with vehicle versus 1.65±0.10 with angiotensin II or 1.31±0.13 with arachidonic acid; P
NCBI GEO: archive for functional genomics data sets—update

The Gene Expression Omnibus (GEO, http://www.ncbi.nlm.nih.gov/geo/) is an international public repository for high-throughput microarray and next-generation sequence functional genomic data sets submitted by the research community. The resource supports archiving of raw data, processed data and metadata which are indexed, cross-linked and searchable. All data are freely available for download in a variety of formats. GEO also provides several web-based tools and strategies to assist users to query, analyse and visualize data. This article reports current status and recent database developments, including the release of GEO2R, an R-based web application that helps users analyse GEO data.
The Streptococcus gordonii Surface Proteins GspB and Hsa Mediate Binding to Sialylated Carbohydrate Epitopes on the Platelet Membrane Glycoprotein Ibα

Platelet binding by Streptococcus gordonii strain M99 is dependent on expression of the cell wall-anchored glycoprotein GspB. This large cell surface protein is exported from the M99 cytoplasm via a dedicated transport system that includes SecA2 and SecY2. GspB is highly similar to Hsa, a protein expressed by S. gordonii Challis that has been characterized as a sialic acid binding hemagglutinin. In this study, we compared the contribution of GspB and Hsa to the adherence of S. gordonii to selected glycoproteins. Our results indicate that GspB can mediate binding to a variety of sialylated glycoproteins. GspB facilitates binding to carbohydrates bearing sialic acid in either α(2-3) or α(2-6) linkages, with a slight preference for α(2-3) linkages. Furthermore, GspB readily mediates binding to sialic acid residues on immobilized glycocalicin, the extracellular portion of the platelet membrane glycoprotein (GP) Ibα (the ligand binding subunit of the platelet von Willebrand factor receptor complex GPIb-IX-V). Although Hsa is required for the binding of S. gordonii Challis to sialic acid, most of the Hsa expressed by Challis is retained in the cytoplasm. The deficiency in export is due, at least in part, to a nonsense mutation in secA2. Hsa export can be enhanced by complementation with secA2 from M99, which also results in significantly greater binding to sialylated glycoproteins, including glycocalicin. The combined results indicate that GspB and Hsa contribute similar binding capabilities to M99 and Challis, respectively, but there may be subtle differences in the preferred epitopes to which these adhesins bind.
Infectious complications after pulsatile-flow and continuous-flow left ventricular assist device implantation

BACKGROUND: Infection is a significant source of morbidity and mortality after left ventricular assist device (LVAD) implantation. Newer generation continuous-flow (CF) LVADs are smaller, requiring smaller pump pockets and drive-line exit sites as compared with pulsatile-flow (PF) devices. With their recent adoption, CF device patients benefit from improved provider experience in the detection and treatment of infectious complications. Given these advances in design and experience, we examined the incidence of infectious complications in patients receiving CF and PF devices. METHODS: We reviewed patients who received CF or PF LVADs (June 2000 to May 2009) at our institution. Incidences and timing of systemic infections (bacteremia, sepsis, severe sepsis, septic shock), device-associated infections (drive-line, LVAD pocket, sternal wound) and non-device-associated infections (catheter-related bloodstream, pneumonia, urinary tract) were compared between devices. Primary outcomes were sepsis, severe sepsis, a composite of drive-line and LVAD pocket infection, and catheter-related bloodstream infection. RESULTS: Of 133 LVADs, 86 were CF. CF patients had lower pre-operative risk, more recent device implantation, and longer LVAD support time. Device type was highly correlated with reduced infections; however, on multivariate analysis, implantation date appeared to drive this association. Kaplan-Meier estimates of freedom from all primary outcomes were improved with more recent implantation (p < 0.05). On multivariate analysis, implantation date was predictive of all primary outcomes except severe sepsis, for which advanced age and worse Seattle Heart Failure Model score were predictive. CONCLUSION: In this institutional review of post-LVAD infections, a decrease in infectious complications in CF patients was likely related to increased provider experience associated with a more recent date of implantation.
An expert system based load monitoring and scheduling system for load balancing in distributed systems

It is argued that an expert system provides an ideal architecture for distributed control where each controller has to use information about the state of other decision makers to reach a common goal. It is suggested that an expert system is a viable tool for distributed problem solving where each solver has to monitor the state of other solvers and make decisions based on its approximate knowledge about other solvers. The authors illustrate this approach by taking the example of distributed load balancing. They present an expert-system-based architecture for load balancing in distributed systems. The system showed promising results during preliminary analysis. The system currently contains about 20 specialists and promises to be exceptionally robust and easily scalable. It is extremely fault tolerant and can function effectively in a changing environment. >
SARS coronavirus: a new challenge for prevention and therapy

A new and deadly clinical syndrome now called severe acute respiratory syndrome (SARS) was brought to the attention of the WHO by Dr. Carlo Urbani and his colleagues in a Vietnamese hospital in February 2003 (1). The WHO, the medical staffs in hospitals where the disease had appeared, and local and regional governments, together with a dozen cooperating laboratories across the globe, immediately responded. They provided a provisional case definition to identify the extent and geographic distribution of the outbreak (2), laboratory investigations to identify the infectious agent, and travel advisories and quarantines to limit the spread of the disease (3, 4). This extraordinary and effective collaboration limited the potentially explosive spread of the outbreak, while initial case reports with clinical and epidemiological information were quickly posted on the Internet to help physicians identify additional cases of the new syndrome (2, 4–9). The press and scientific journals played valuable roles in rapidly distributing accurate information about SARS to the frightened public and making key scientific publications about SARS available via the Internet before they could appear in print. A stroke of good fortune in this crisis was the discovery that a novel virus could be readily isolated from patients’ lungs and sputum and cultivated in a monkey kidney cell line (8, 10, 11). Laboratory investigations using electron microscopy, virus-discovery microarrays containing conserved nucleotide sequences characteristic of many virus families, randomly primed RT-PCR, and serological tests quickly identified the virus as a new coronavirus (8, 10, 11). Inoculation of monkeys with the SARS-associated coronavirus (SARS-CoV) caused interstitial pneumonia resembling SARS, and the virus was isolated from the nose and throat (12). No viral or bacterial copathogen was needed to induce the disease. These experiments fulfilled Koch’s postulates and proved that SARS-CoV is the cause of SARS.
To preempt or not: Tackling bid and time-based cheating in online spectrum auctions

Online spectrum auctions offer ample flexibility for bidders to request and obtain spectrum on-the-fly. Such flexibility, however, opens up new vulnerabilities to bidder manipulation. Aside from rigging their bids, selfish bidders can falsely report their arrival time to game the system and obtain unfair advantage over others. Such time-based cheating is easy to perform yet produces severe damage to auction performance. We propose Topaz, a truthful online spectrum auction design that distributes spectrum efficiently while discouraging bidders from misreporting their bids or time report. Topaz makes three key contributions. First, Topaz applies a 3D bin packing mechanism to distribute spectrum across time, space and frequency, exploiting spatial and time reuse to improve allocation efficiency. Second, Topaz enforces truthfulness using a novel temporal-smoothed critical value based pricing. Capturing the temporal and spatial dependency among bidders who arrive subsequently, this pricing effectively diminishes gain from bid and/or time-cheating. Finally, Topaz offers a “scalable” winner preemption to address the uncertainty of future arrivals at each decision time, which significantly boosts auction revenue. We analytically prove Topaz's truthfulness, which does not require any knowledge of bidder behavior, or an optimal spectrum allocation to enforce truthfulness. Using empirical arrival and bidding models, we perform simulations to demonstrate the efficiency of Topaz. We show that proper winner preemption improves auction revenue by 45–65% at a minimum cost of spectrum utilization.
A Review of: “Failure Analysis Case Studies, D. R. H. Jones (Ed.)”

The author of this book compiles 36 case studies that go on to adequately describe the analysis of engineering failures experienced in structures made from a spectrum of materials. The case studies...
Identifying Rates of Emigration in the United States Using Administrative Earnings Records

This paper undertakes a new strategy to estimate emigration rates among US immigrants by inferring the probability of emigration using longitudinal administrative earnings data. Two groups of emigrants are evaluated separately: those who emigrate from the United States and those who leave both the United States and the Social Security system. About 1.0 to 1.5 percent of the foreign-born population emigrate from the USA every year, and between about 0.8 and 1.2 percent of foreign-born workers emigrate from the Social Security system. Regression analysis suggests that immigrants with lower earnings are more likely to emigrate and that the likelihood of emigrating from the United States increases with age, but is unchanged for those leaving the US Social Security system.
Mechanical behavior of a highly oriented polyethylene rod

Dynamic mechanical and single step stress relaxation data are presented for a highly oriented linear polyethylene rod as produced by a high pressure extrusion technique. The results indicate that both major relaxation processes normally observed in unoriented polyethylene are virtually absent in torsion, whereas they are present in flexure. Stress relaxation in torsion data show a very highly nonlinear behavior when compared to similar data for an unoriented polyethylene rod.
The Specificity of Environmental Influence: Socioeconomic Status Affects Early Vocabulary Development Via Maternal Speech

The hypothesis was tested that children whose families differ in socioeconomic status (SES) differ in their rates of productive vocabulary development because they have different language-learning experiences. Naturalistic interaction between 33 high-SES and 30 mid-SES mothers and their 2-year-old children was recorded at 2 time points 10 weeks apart. Transcripts of these interactions provided the basis for estimating the growth in children’s productive vocabularies between the first and second visits and properties of maternal speech at the first visit. The high-SES children grew more than the mid-SES children in the size of their productive vocabularies. Properties of maternal speech that differed as a function of SES fully accounted for this difference. Implications of these findings for mechanisms of environmental influence on child development are discussed. Family socioeconomic status (SES) is a powerful predictor of many aspects of child development. An aim of current research is to identify the pathways by which SES exerts its well-established influence (DeGarmo, Forgatch, & Martinez, 1999; Keating & Hertzman, 1999; Linver, Brooks-Gunn, & Kohen, 2002; National Research Council and Institute of Medicine, 2000). Because SES and child development are multifaceted variables and because many factors that influence child development covary with SES, the causal relations underlying SES effects on child development may be difficult to uncover (Hoff, Laursen, & Tardif, 2002). The present study focused on one reliably observed relation between SES and child development and sought to identify the underlying mechanism. The relation in focus is that between SES and early
Partner influence on early discontinuation of the pill in a predominantly Hispanic population

Context: Although studies have examined U.S. pill users patterns of discontinuation little is known about pill discontinuation and the effects of partner influence among Hispanics. Methods: Follow-up data on pill use were collected from 213 predominantly Hispanic women who requested the pill in an urban family planning clinic in 2000. Logistic regression analyses were conducted to assess the association between a range of factors including partner and relationship variables and the odds that women discontinued use before starting their second pack of pills. Results: The overall rate of early discontinuation was 23%. Women who reported that their partner was unaware of their planned pill use had significantly elevated odds of discontinuing use (odds ratio 3.4). Other variables that were independently associated with increased odds of early pill discontinuation were not taking the first pill during the clinic visit (3.0) feeling happy about the prospect of a pregnancy in the next six months (2.4) and intending to use the pill for one year or less (2.3). Age which was assessed as a continuous variable was negatively associated with the odds of early discontinuation (0.9). Conclusions: Male partners awareness of planned pill use may be a marker for the level of communication and commitment in the relationship. Women may choose to disclose their planned pill use to supportive partners and this may be beneficial to the relationship and the couples contraceptive use. However clinicians should take womens circumstances and needs into account before counseling them to tell a partner that they intend to use the pill. (authors)
Design strategies and preliminary prototype for a low-cost arsenic removal system for rural Bangladesh.

Researchers have invented a material called ARUBA -- Arsenic Removal Using Bottom Ash -- that effectively and affordably removes arsenic from Bangladesh groundwater. Through analysis of studies across a range of disciplines, observations, and informal interviews conducted over three trips to Bangladesh, we have applied mechanical engineering design methodology to develop eight key design strategies, which were used in the development of a low-cost, community-scale water treatment system that uses ARUBA to remove arsenic from drinking water. We have constructed, tested, and analysed a scale version of the system. Experiments have shown that the system is capable of reducing high levels of arsenic (nearly 600 ppb) to below the Bangladesh standard of 50 ppb, while remaining affordable to people living on less than US$2/day. The system could be sustainably implemented as a public-private partnership in rural Bangladesh.
Evaluating Norms: An Empirical Analysis of the Relationship between Norm-Content, Operator, and Charitable Behavior

There are several kinds of norms, and this variety can lead to spirited debate about the best norm to employ for the regulation of a particular activity. Should the norm be mandatory or aspirational? A rule or a standard? One important area in which norm-choice has come to the fore is the American Bar Association’s oversight of pro bono work. Currently, the organization utilizes an aspirational norm recommending that lawyers perform at least fifty pro bono hours annually, but there is pressure to adopt some sort of mandatory rubric. Inspired by this debate, we have designed and implemented an experiment that provides some insight into the effective design of norms for charitable giving. Our results challenge the conventional wisdom that the implementation of a mandatory framework will result in an overall increase in giving. These findings may be applicable not only to the pro bono debate but also to general legislative strategy with respect to inducement of charitable behavior.Prior empirical studies that have analyzed the effect of norm characteristics on behavior have typically pitted rules against standards. We placed these two norm-content classes in combination with two kinds of operators: aspirational and mandatory. Thus, we tested four norm combinations, each one representative of norms in important rubrics such as legal systems and codes of ethics. Through this more complex model, our results contribute to the literature on two psychological phenomena, motivation crowding and anchoring, that affect the way people respond to norms.We found that, in the context of inducing charitable behavior, it is more effective to use an aspirational rather than a mandatory operator when the operator is conjoined with moral norm-content. Additionally, we found that the effectiveness of norms that utilize mandatory operators is contingent upon the kind of norm-content that they employ, whether moral or bright-line, and that this is not true with norms utilizing aspirational operators. Lastly, the deficit in effectiveness that arises from using mandatory operators in conjunction with moral norm-content can be overcome by switching to bright-line norm-content, but only if the minimums are set very high. Our results support the view that norms can induce crowding out, leading to less charitable conduct than would have occurred under an aspirational system. They also illustrate a context in which aspirational norms are resistant to anchoring effects.
Prevalence and correlates of depression and drinking behaviors among adolescents and emerging adults in a suburban emergency department

ABSTRACTBackground: Both alcohol use and depression are concerning health issues among youth. The Emergency Department (ED) is a critical location to access youth with depressive symptoms and alcohol misuse. Objectives: To inform future interventions in the ED, this study examined the relationship between drinking behaviors and depressive symptoms among youth seeking ED care. Methods: Youth ages 14–20 were recruited from a level-1 trauma ED located in the Midwest as part of a larger ongoing study. Participants completed an electronic screening survey, which included assessment of alcohol use, depressive symptoms, and demographic variables. Two logistic regression models were conducted to assess the relationship between depressive symptoms with alcohol consumption and specific alcohol-related consequences. Results: Among 3,659 participants, bivariate analysis indicated that individuals screening positive for depression were more likely to be female, nonwhite, receive public assistance, and report higher sc...