cssi/SciSciGPT-SciSciNet huggingface dataset:
Movement of the Nucleotide Binding Domains in the Reconstituted ABC Transporter MsbA During the ATP-Hydrolysis Cycle

ATP-binding cassette (ABC) transporters move substrates across membranes, including nutrients, toxins, peptides and small inorganic ions. MsbA is a homodimeric bacterial lipid flippase homolog of P-glycoprotein, a transporter involved in multidrug resistance. ABC transporters are formed by two transmembrane domains and two highly conserved nucleotide binding domains (NBDs) that bind and hydrolyze ATP. Crystal structures have shown widely separated NBDs (open conformation; nucleotide-free state) and NBDs forming a dimer with nucleotide trapped at the interface (closed conformation, nucleotide-bound), leading to the proposal of a switch model, where NBDs associate/dissociate during the ATP hydrolysis cycle. Other proposed mechanisms suggest instead that the NBDs are always in contact. Recent studies using Luminescence Resonance Energy Transfer (LRET) in detergent-solubilized MsbA have shown transitions between completely separated and dimeric NBD, in agreement with the switch-model (Cooper & Altenberg, 2013. JBC 287:14994). Here, we used LRET to determine if complete NBD separation also occurs when MsbA is reconstituted in a membrane. Basically, the single cysteine MsbA (T561C) was labeled with LRET donor and acceptor probes, reconstituted in nanodiscs, and the donor-acceptor distance was determined at different steps during the ATP hydrolysis cycle. The reconstituted protein displayed higher ATPase activity than MsbA in detergent. Donor-acceptor distances in nucleotide-free and nucleotide-bound states, as well as during hydrolysis conditions (MgATP), indicated small distance changes, consistent with a partial opening of the NBD dimers. There was no evidence for the longer distance (>50 A) observed in the open conformation and in detergent. These results show a dramatic effect of the lipid bilayer on the molecular mechanism of MsbA, and suggest that the NBDs remain in close proximity during the hydrolysis cycle under more "physiological" conditions. This work was supported by CPRIT grant RP101073.
Inference gaps in moral assessment: capitalism, corporations and individuals

The paper is divided into three parts. In the first an argument is made that negative moral assessments of institutions are insufficient bases from which to infer similar negative moral assessments of the actions of the organizations that embody those institutions or the individuals that perform institution-constituted actions within those institutions. The second part re-examines arguments for organizational intentionality and hence organizational membership in the moral community that the author had presented over two decades ago and offers a revision of the author's position on organizational intentionality that is intended to be more intuitively pleasing than his former account that was based on understanding intentionality on the desire/belief complex model. The third part draws some of the consequences of the inference gaps in moral assessment for understanding the complexity of the elements of the moral world.
Isotopic and rock magnetic expression of environmental change at the Pleistocene–Holocene transition in the central Great Plains

Abstract In a region too dry for the effective use of the traditional palynological approach, loess deposits of the central Great Plains offer a source of proxy information for the reconstruction of past climates. The Brady soil, a ubiquitous feature developed within the uppermost, late-Pleistocene Peoria loess, recorded the character of vegetation change associated with climate shifts during the Pleistocene–Holocene transition. Stable carbon isotope ratio analysis and two, room-temperature magnetic parameters were used to examine the nature of the change during this period. δ 13 C values derived from soil organic matter indicate that in the late Pleistocene minor populations of drought tolerant (C4) plants were interspersed among the dominant cool-season grasses (C3) in the west, while C3 grasses were accompanied by trees in the east. By the early Holocene, C4 grasses were the dominant vegetation in the west and contributed substantially to the δ 13 C signal in the east. Magnitude of the δ 13 C shift suggests an increase in July mean daily temperature of 8–10°C, according to existing models. Magnetic susceptibility and frequency dependence signal the cessation of loess deposition and development of the Brady soil, and indicate a spatial pattern in the intensity of weathering across the region.
Nuclear relaxation and critical fluctuations in membranes containing cholesterol

Nuclear resonance frequencies in bilayer membranes depend on lipid composition. Our calculations describe the combined effects of composition fluctuations and diffusion on nuclear relaxation near a miscibility critical point. Both tracer and gradient diffusion are included. The calculations involve correlation functions and a correlation length ξ=ξ0T/(T−Tc), where T−Tc is temperature above the critical temperature and ξ0 is a parameter of molecular length. Several correlation functions are examined, each of which is related in some degree to the Ising model correlation function. These correlation functions are used in the calculation of transverse deuterium relaxation rates in magic angle spinning and quadrupole echo experiments. The calculations are compared with experiments that report maxima in deuterium and proton nuclear relaxation rates at the critical temperature [Veatch et al., Proc. Nat. Acad. Sci. U.S.A. 104, 17650 (2007)]. One Ising-model-related correlation function yields a maximum 1/T2 relax...
ARGO: aging-aware GPGPU register file allocation

State-of-the-art general-purpose graphic processing units (GPGPUs) implemented in nanoscale CMOS technologies offer very high computational throughput for highly-parallel applications using hundreds of integrated on-chip resources. These resources are stressed during application execution, subjecting them to degradation mechanisms such as negative bias temperature instability (NBTI) that adversely affect their reliability. To support highly parallel execution, GPGPUs contain large register files (RFs) that are among the most highly stressed GPGPU components; however we observe heavy underutilization of RFs (on average only 46%) for typical general-purpose kernels. We present ARGO, an Aging-awaRe GPGPU RF allOcator that opportunistically exploits this RF underutilization by distributing the stress throughout RF. ARGO achieves proper leveling of RF banks through deliberated power-gating of stressful banks. We demonstrate our technique on the AMD Evergreen GPGPU architecture and show that ARGO improves the NBTI-induced threshold voltage degradation by up to 43% (on average 27%), that yields improving RFs static noise margin up to 46% (on average 30%). Furthermore, we estimate a simultaneous reduction in leakage power of 54% by providing sleep states for unused banks.
Music in the Operating Room: Harmony or Discord?

The role of music in the operating room (OR) has a history that is almost 100 years old. It has been alternately lauded and disparaged. Music has been said to decrease the attention to a patient’s status or to improve the vigilance of the anesthesiologist and efficiency of the surgeon. Many ORs became “wired for sound” decades ago; this is not a new concept in this era of “boom boxes” and iPods®. In 1914 Dr. Burdick, an anesthesiologist, was credited with placing the first phonograph in an OR.1 A surgeon, Dr. Kane, complimented him by stating that “his selection of records admirably adapted to the tastes and temperament of the (patients).” Music was a “means of calming and distracting my patients from the horror of the situation when going under the anesthetic and during operations performed partially or entirely with local anesthesia.” This was especially of benefit for a nervous and anxious patient. Also, it allowed the operating staff to concentrate on the surgical procedure and not on having to verbally calm or restrain the patient. As Dr. Kane stated, “it is not uncommon for nervous patients to beg to have the phonograph continue, should it run down, and many of them converse animatedly with the anesthetist on the subject of the pieces being played throughout the entire operation.” Subsequently, Dr. Burdick described how a patient entering the OR is often tearful “with such feelings of horror and dread as to be on the verge of collapse.”2,3 After noting the beneficial effects of music in hospital wards, he described how a phonograph in the OR functioned “as a diversionary means during operation under local anesthesia.” (Figure 1) He stated that 95% of patients desired to hear music, and only 2% objected. Preoperatively he talked with the patient to ascertain the appropriate music and played this in a subdued tone. Allowing patients who were undergoing procedures with local anesthesia to listen to music and be pleasantly distracted meant that it was not necessary for the surgeon and anesthetist to keep the patient distracted. Dr. Burdick used soft music to assist with inhalational inductions and emergence during general anesthesia, although not all patients were helped. MuFig. 1. Showing the use of the phonograph during an operation under local analgesia in the surgical clinic of the Kane Hospital. (From reference 3, courtesy of Patrick Sim and the Wood Library-Museum of Anesthesiology.).
Random effects meta analysis of military recruiting

The success of the US military recruiting depends not only on recruiting efforts but also on the labor market conditions. In this paper we review the econometric literature that examined the effects of marketing as well as recruiting effort on high quality enlistment contracts in the 1980s. A random-effects meta analysis is used to examine the systematic variation across studies of advertising, recruiter effort, and unemployment rate elasticities. The result of a meta analysis indicates that (1) the estimated effect of unemployment rate on military recruiting does not vary significantly over several military recruiting studies; (2) the average elasticity of high quality contract with respect to unemployment rate is estimated as 0.48; (3) elasticities of high quality contract with respect to advertising and recruiter forces are influenced by individual study characteristics; (4) although the Army recruiter elasticity (0.43) turns out to be higher than advertising elasticity (0.15), Army advertising appears to cost slightly less than recruiter forces on average when an additional contract is needed. However, this cost difference is not significant.
Disorder-Induced Time-Dependent Diffusion in Zeolites

We suggest that disordered framework aluminums and nonframework cations can create a disordered electrostatic potential in zeolites that can lead to a discrepancy between diffusivities measured by microscopic and macroscopic experimental techniques. We calculate the value of the discrepancy and the characteristic time scale at which it occurs for several ionic and polarizable species diffusing in zeolites. For ionic species, a discrepancy is almost inevitable. For polarizable species, a significant discrepancy may occur in some zeolites only for long alkanes or large species such as benzene.
EXPERIMENTS ON THE PRODUCTION OF SPECIFIC ANTISERA FOR INFECTIONS OF UNKNOWN CAUSE : III. THE EFFECTS OF A SERUM PRECIPITIN ON ANIMALS OF THE SPECIES FURNISHING THE PRECIPITINOGEN.

There is present in serum of high precipitin titer, produced by the repeated injection of rabbits with the blood-free serum of guinea pigs or dogs, a principle highly toxic for animals of the species furnishing the antigen. Intravenously the serum causes severe shock, and even sudden death, while locally it gives rise to acute inflammatory changes and profuse capillary hemorrhages. The complete removal of hemolysins and hemagglutinins from the serum by exposing it repeatedly to washed red cells lessens its toxicity to only a slight degree and one obviously dependent on these elements; while the further removal of precipitin by specific precipitation in vitro has no detoxifying effect whatever. Whether the toxic principle is a hitherto unrecognized antibody or perhaps a toxic product of the interaction of precipitin and precipitinogen,—one formed as readily in the test-tube as in the animal body,—remains to be determined. The symptoms of guinea pigs and dogs given an intravenous injection of treated or untreated serum markedly resemble those of anaphylaxis, but our attempts at desensitization have been unsuccessful. The local lesion in guinea pigs is more severe than that of the Arthus phenomenon. But these differences from anaphylaxis may, of course, be dependent merely on differing proportions of constituents that are themselves, as yet, scarcely apprehended. Our observations, as here summed up, were made with a practical point in mind, and as regards this point they are of a discouraging nature. In papers already published it has been shown that sera specifically effective against infections of which the excitant is unknown can in some cases be obtained by using infected tissue itself as antigen. Such sera must, of course, be deprived of antibodies injurious to tissue, prior to their employment in the animal body; and this was successfully accomplished in our early experiments by exhaustion with washed red cells. The purpose of the present work was to determine whether serum used as antigen gives rise to injurious principles in the antiserum. For the serum of infected individuals would in many diseases form a convenient antigen. It is evident that injurious principles result from its use, and that they are not removed from the antiserum when the latter is exhausted with red cells and its precipitin removed by specific precipitation, nor can their action be nullified by desensitization as carried out in anaphylaxis. Unless the obstacle of their presence is in some way overcome the body fluids of infected human beings cannot be practically utilized for the production of antiserum. In test animals the difficulty is not so grave. For we have found that the toxic antiserum produces no enduring lesions when it is administered intravenously in non-lethal doses.
Ligand Binding Sites on Guinea Pig C3aR: Point and Deletion Mutations in the Large Extracellular Loop and Vicinity

Human C3a receptor (huC3aR) belongs to the G-protein coupled receptor family chacterized by having seven transmembrane domains. The huC3aR is a unique member of this family having a large extracellular (EC) loop of 175 amino acids between the 4th and 5th transmembrane domains. Based on a comparison of C3aR sequences from several species, a number of charged and conserved amino acids (Asp182, Asp309, Asp310, and Arg331) in and near the large EC loop of guinea pig C3aR were replaced using site-directed mutagenesis. Competitive binding assays showed that changing Arg331 in guinea pig C3aR to Ala (or Gln), but not changing Asp182, Asp309, or Asp310 to Ala, resulted in complete loss of ligand binding activity. These results and major EC loop deletions demonstrated that an essential C3a binding site is present in the transmembrane portion of C3aR, but not in the large EC loop. Replacement of Arg331 by a noncharged residue was sufficient to eliminate ligand-receptor interactions.
Comparison of mixing efficiency and vertical diffusivity models from temperature microstructure

[1] Due to the many difficulties associated with measuring buoyancy flux directly in the field, parameterizations for the flux involving eddy diffusivities are commonly used. These parameterizations are often cast in terms of a mixing efficiency (Γ), which itself is often assumed to be a constant throughout the water column (0.17–0.2). Alternatively, Γ can be calculated in terms of turbulence parameters which attempt to capture the varying mixing dynamics throughout the water column. In this paper three separate parameterizations are used to calculate the eddy diffusivities in a dynamically evolving stratified water column in the Gulf of Aqaba. Furthermore, we use two different approaches for calculating Γ by Ivey and Imberger (1991) and Shih et al. (2005) for these diffusivity parameterizations and compare the results obtained using each approach. Further work on the Shih et al. (2005) parameterization by D. Bouffard and L. Boegman (personal communication, 2011) has also been used in this analysis. While direct measurements of buoyancy flux are needed to validate the actual accuracy of the mixing efficiency parameterizations, we can make the following conclusions. First, we found that in some circumstances the eddy diffusivity models produce very different estimates from one another and the estimates are themselves sensitive to the choice of parameterization for Γ. Second, when the stratification is weak and temperature variance is small, parameterizations involving calculations of the Thorpe scale, χT as well as the turbulent Froude number and Reynolds numbers should be treated with great caution. Third, under the same circumstances, the Shih et al. (2005) approach for Γ applied to the κρ parameterization for vertical diffusivity seems to be the best vertical diffusivity (based on a comparison to κχ).
Assessing the global threat of invasive species to marine biodiversity

Although invasive species are widely recognized as a major threat to marine biodiversity, there has been no quantitative global assessment of their impacts and routes of introduction. Here, we report initial results from the first such global assessment. Drawing from over 350 databases and other sources, we synthesized information on 329 marine invasive species, including their distribution, impacts on biodiversity, and introduction pathways. Initial analyses show that only 16% of marine ecoregions have no reported marine invasions, and even that figure may be inflated due to under-reporting. International shipping, followed by aquaculture, represent the major means of introduction. Our geographically referenced and publicly available database provides a framework that can be used to highlight the invasive taxa that are most threatening, as well as to prioritize the invasion pathways that pose the greatest threat.
Spatial summation of heat pain within and across dermatomes in fibromyalgia patients and pain-free subjects.

Abstract The mechanisms of spatial summation of pain (SSP) include pain coding dependent on impulse frequency and the number of recruited central neurons. However, SSP may also be influenced by pain inhibitory mechanisms, such as diffuse noxious inhibitory controls. Abnormal interactions between pain inhibitory mechanisms and SSP may be relevant for chronic pain conditions such as fibromyalgia (FM) and may help explain why widespread pain is characteristic for this chronic pain syndrome. The present study was designed to determine the difference of thermal SSP in the upper extremities between FM and normal control (NC) subjects, particularly within and across dermatomes of the hand. Fourteen NC and 19 FM subjects were enrolled in this study. SSP testing sessions involved immersion of each individual fingertip as well as stepwise immersion of the fingers, hands, and forearms in a hot water bath (46 °C) for 5s and 20s. In addition, immersion of several fingertips across dermatome C 7 –C 8 was compared to progressive immersion of the index finger (dermatome C 7 ). These experiments demonstrated significant spatial summation of heat-induced pain in both FM and NC subjects. SSP was most extensive within the fingers, and became negligible as the stimulus area increased above the hand. Furthermore, SSP was more pronounced within one dermatome such as that of the index finger than across several dermatomes of the hand. These results were similar for both FM and NC subjects. Thus, mechanisms of SSP, including possible inhibitory factors that limit this relevant pain mechanism, appear to be similar for both FM and NC subjects.
The Ankyrin Repeat Domain of the TRPA Protein Painless Is Important for Thermal Nociception but Not Mechanical Nociception

The Drosophila TRPA channel Painless is required for the function of polymodal nociceptors which detect noxious heat and noxious mechanical stimuli. These functions of Painless are reminiscent of mammalian TRPA channels that have also been implicated in thermal and mechanical nociception. A popular hypothesis to explain the mechanosensory functions of certain TRP channels proposes that a string of ankyrin repeats at the amino termini of these channels acts as an intracellular spring that senses force. Here, we describe the identification of two previously unknown Painless protein isoforms which have fewer ankyrin repeats than the canonical Painless protein. We show that one of these Painless isoforms, that essentially lacks ankyrin repeats, is sufficient to rescue mechanical nociception phenotypes of painless mutant animals but does not rescue thermal nociception phenotypes. In contrast, canonical Painless, which contains Ankyrin repeats, is sufficient to largely rescue thermal nociception but is not capable of rescuing mechanical nociception. Thus, we propose that in the case of Painless, ankryin repeats are important for thermal nociception but not for mechanical nociception.
Inhibition of phagocytosis by aureomycin.

SummaryPhagocytosis of Micrococcus pyogenes var. albus cells by polymorphonuclear leucocytes was markedly inhibited by aureomycin in a concentration of 1000 μg/ml in vitro. This inhibition, although less pronounced, was still significant in concentrations of the antibiotic which were considerably lower than the therapeutic blood levels ordinarily employed in clinical practice.
Prediagnostic circulating sex hormones are not associated with mortality for men with prostate cancer

Background Sex hormones play an important role in the growth and development of the prostate, and low androgen levels have been suggested to carry an adverse prognosis for men with prostate cancer (PCa).
Predation risk in tadpole populations shapes behavioural responses of prey but not strength of trait-mediated indirect interactions

Prey animals often respond to predators by reducing activity levels. This can produce a trait-mediated indirect interaction (TMII) between predators and prey resources, whereby reduced foraging by prey in the presence of a predator causes an increase in prey resources. TMIIs play important roles in structuring communities, and it is important to understand factors that determine their strength. One such influence may be behavioural variation in the prey species, with indirect effects of predators being stronger within populations that are more responsive to the presence of a predator. We tested 1) whether the behavioural responsiveness of populations of wood frog tadpoles to predator cues was related to the predation risk in their native ponds, and 2) whether more responsive tadpoles yielded stronger TMIIs. To do this, we 1) measured the activity of tadpoles from 18 populations in mesocosms with and without caged predators, and 2) measured changes in the biomass of periphyton (the tadpoles’ diet) between predator treatments for each population. We found that tadpoles from higher predation risk ponds reduced their time outside refuges more in the presence of predators and tended to move less when visible, suggesting possible local adaptation to predation regimes. Though the presence of predators generally resulted in higher periphyton biomass – a TMII – there was no evidence that the strength of this TMII was affected by variation in tadpole behaviour. Foraging activity and general activity may be decoupled to some extent, enabling high predation risk-adapted tadpoles to limit the fitness costs of reduced foraging when predators are present.
A study of error sources in current steering digital-to-analog converters

This work discusses a number of error sources which potentially limit the distortion and SNR performance of modern current steering digital-to-analog converter designs. Static matching errors, as well as timing and non-linear output impedance errors, are presented along with possible design solutions.
Organizational economics: applications to metropolitan governance

This comment relates to Richard Posner (2010), the lead article for this issue. Posner applies ‘the principles of organization economics’ to the study of diverse types of organizations. His study comparing the FBI to other types of police organization is important and compatible with the study of urban policing in American metropolitan areas. Many policy prescriptions are based on an inadequate understanding of the diversity of urban public good production functions and a lumping together of every type of police service. A brief review of research related to the concept of polycentricity as related to urban services in metropolitan areas is provided as a way of further illustrating Posner's concern that finer distinctions need to be made in the way scholars analyze organizational economics.
Effects of Rose Cultivars and Fertilization Rates on Populations of Scirtothrips dorsalis (Thysanoptera: Thripidae) in Southern Florida

ABSTRACT Roses (Rosa spp. L.) are important ornamental hosts of chilli thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae). The knowledge of how these thrips affect 8 cultivars of landscape roses popular in Florida (‘Angel Face’, ‘Don Juan’, ‘Pink Summer Snow’, ‘Radeon’, ‘Radrazz’, ‘Radsunny’, ‘St. Patrick’, and ‘Sun Flare’) would help in developing techniques for integrated pest management of S. dorsalis. The effects of 3 rates of fertilizer and cultivars on population densities of chilli thrips and on host plant damage were evaluated. Fertilization rate, plant organ, and cultivar were important in determining S. dorsalis population density. Differences in total numbers of S. dorsalis, damage rating, and in numbers of flowers and buds produced were observed among different fertilizer rates. The higher rates recommended for accelerated floral growth resulted in more S. dorsalis damage, but not in more flowers than the rates suggested for maintenance. Among parts of the rose plant, buds had the hi...
Renin-Dependent Hypertension Caused by Nonfocal Stenotic Aberrant Renal Arteries. Proof of a New Syndrome

We have identified 2 relatively young patients with significant hypertension, an elongated single aberrant renal artery supplying blood to a renal segment, and evidence for localization of the elevated plasma renin activity to the side and vein draining the affected kidney. Furosemide-induced diuresis and acute oral captopril stimulated the renal vein/contralateral renin ratios to 4.3:1 and 6.5:1 in patients 1 and 2, respectively. These renal vein ratios are significantly higher than normal (>3:1 under similar conditions). Partial resection of the portion of the kidney affected by the aberrant tortuous artery led to a marked reduction in blood pressure in patient 1. Patient 2, not an operative candidate, responded satisfactorily to use of a converting enzyme inhibitor, which helped to confirm the dependency of the blood pressure on the abnormal flow relationship existing within that aberrant artery and the kidney. We believe these 2 patients are representative of a small but distinct subgroup within the larger number of patients with elongated single or multiple renal aberrant arteries. Each aberrant artery had no focal stenosis, although a decrease in flow relative to the tissue perfusion demands was apparent from the marked activation of the renin-angiotensin system in the venous system draining that artery. The increased length of such vessels may contribute to their decreased flow, although their average diameter may reside just above such a critical value for a normal length vessel. This new syndrome, involving more than one component of the flow/resistance relationship, has been overlooked when renin-dependent forms of hypertension are considered.
Microbial Transformations of Uranium Complexed with Organic and Inorganic Ligands

Biotransformation of various chemical forms of uranium present in wastes, contaminated soils and materials by microorganisms under different process conditions such as aerobic and anaerobic (denitrifying, iron-reducing, fermentative, and sulfate-reducing) conditions will affect the solubility, bioavailability, and mobility of uranium in the natural environment. Fundamental understanding of the mechanisms of microbial transformations of uranium under a variety of environmental conditions will be useful in developing appropriate remediation and waste management strategies as well as predicting the microbial impacts on the long-term stewardship of contaminated sites.
Ionic matrices for matrix-assisted laser desorption/ionization time-of-flight detection of DNA oligomers.

Salts with low melting points, also termed room-temperature ionic liquids, can be used as matrices in matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF). They have great vacuum stability, and can dissolve polar and apolar solutes including carbohydrates, biological oligomers and proteins. The ionic liquids give much more homogeneous sample solutions compared with solid matrices. We demonstrate the usefulness of using ionic matrices to determine the molecular weight of DNA oligomers by direct TOF mass spectrometric analysis. Three oligonucleotides were tested, (d(pT)10, d(pC)11, and d(pC)12), with several ionic matrices synthesized from different bases associated to two acids (3-hydroxypicolinic acid and 2,5-dihydroxybenzoic acid). The results obtained show that the best ionic matrices enhance the ion peak intensity of the oligonucleotides with respect to conventional molecular matrices under our experimental conditions. In one case, an ionic matrix provided a signal-to-noise ratio ten times higher than the corresponding molecular matrix. Several of the tested ionic matrices were liquids. However, all working ionic matrices were solids. Copyright © 2003 John Wiley & Sons, Ltd.
The Cultivation of Esteem and Retrieval of Scientific Knowledge in Physician Networks

This article evaluates how physicians draw upon scientific and other forms of knowledge in different professional communities. We argue that because physicians will draw upon clinical research findings to improve their reputation with colleagues, and because the terms for accruing esteem in an academic hospital may differ depending on the dominant task structure of the organization, the form of knowledge that is valued by a physician will vary with his or her hospital's level of prestige. We use social network and multivariate analyses to test this theory in six U.S. hospitals with varying levels of prestige. We find that in lower-prestige hospitals, physicians can improve their reputation by reading a relatively broad range of scientific journals, whereas in higher-prestige hospitals, esteem is allocated to those with a more elite medical school pedigree. Statistically significant differences also exist between hospitals in terms of whether work with patients is valued, with physicians who engage in more clinical activity in the highest-ranked hospitals receiving less esteem from their colleagues. We finish by discussing how the functioning of higher- and lower-prestige hospitals is interconnected in ways that sustain both the development of innovations and their widespread adoption.
Photonic Band Gap Materials

An overview of the theoretical and experimental efforts in obtaining a photonic band gap, a frequency band in three-dimensional dielectric structures in which electromagnetic waves are forbidden, is presented.
Intrusion of saline groundwater into Seneca and Cayuga Lakes, New York

Seneca and Cayuga Lakes have chloride levels 2-l 0 times higher than the other Finger Lakes. Approximately 170 x 1 O6 kg of salt appear to be added to Seneca Lake from within the basin each year. The region is underlain by Silurian beds of commercial-grade rock salt -450-600 m below the surface. It has been proposed that Seneca and Cayuga Lakes are saltier than the others because their basins intersect some of these beds. Fieldwork supports this hypothesis. A deep water mass up to 10% saltier than the rest of Seneca Lake was observed to expand and partially fill the hypolimnion from the bottom up during summer 199 1 and 1992. The saltier water was mixed into the rest of the lake in early winter, only to reappear after the thermocline was established. Sediment interstitial water profiles in both lakes reveal large regions of saline groundwater several meters below the sediment surface, and NaCl concentrations as high as 30?&0 have been found. New York’s Finger Lakes occupy 11 north-south trending basins thought to be preglacial river valleys gouged by Pleistocene glaciation and dammed by moraines (von Engeln 196 1). The basins are extremely deep for their surface area (max depths: Seneca, 188 m; Cayuga, 132 m) and intersect a thick sequence of Paleozoic marine sedimentary rocks that dips gently to the south-southwest with little structural deformation. Seneca and Cayuga Lakes exhibit much higher concentrations of dissolved sodium and chloride than the smaller Finger Lakes do, in spite of similar patterns of land use throughout the region. Berg (1963) has noted that salt strata underlie the entire area and that beds of commercial-grade rock salt 450600 m below ground level are mined at the southern end of both lakes. Because the mines are dry and lie well below the lake floors, he did not consider it probable that groundwater from these depths leaches upward into the lakes. He also considered and rejected the washings from the commercial salt processing plants themselves as the cause, because no point-sources for chlorides were indicated by the salinity distributions in the lakes, and mass balance considerations seemed to preclude it; a source for chlorides much greater than the mines could provide
Fall armyworm FR sequences map to sex chromosomes and their distribution in the wild indicate limitations in interstrain mating

The fall armyworm, Spodoptera frugiperda, consists of two host strains (rice and corn) that differ in developmental, physiological and behavioural characteristics. However, because the strains are morphologically indistinguishable the investigation of strain-specific behaviour, particularly in the wild, is very difficult. This has spurred the isolation of diagnostic molecular markers. FR sequences are tandem-repeat genetic elements found in large clusters only in the rice strain. To facilitate their use as a strain marker we genetically mapped FR clusters and found they localized to the sex chromosomes. This represents one of the first examples of chromosome mapping in fall armyworm. The FR sequence and a strain-specific mitochondrial marker were then used to examine the distribution of different marker combinations in field specimens. These studies identified significant barriers to interstrain mating in the wild, specifically that corn strain females rarely, if ever, mate with rice strain males. The data also suggest that only a genetically distinct subset of the overwintering rice strain population in Florida annually migrate to Georgia. These studies demonstrate that the availability of genetically characterized molecular markers for strain identity makes possible studies on fall armyworm biology in the wild previously considered unfeasible.
Regulation of brain glucose transporters by glucose and oxygen deprivation.

Abstract Brain cells are dependent on glucose and oxygen for energy. We investigated the effects of hypoxia, glucose deprivation, and hypoxia plus glucose deprivation on mRNA and protein levels of glucose transporter (GLUT1) and GLUT3 and 2-deoxyglucose (2-DG) uptake in primary cultures of rat neurons and astroglia. Hypoxia for 24 hours did not significantly affect cell viability but increased neuronal GLUT1 and GLUT3 mRNA up to 40-fold and fivefold, respectively, above control levels. Similar changes in GLUT1 mRNA were measured in glia. The effects of hypoxia on GLUT1 and GLUT3 mRNA were reversible. The increase in GLUT1 mRNA could be detected within 20 minutes of hypoxia and was blocked by actinomycin D. Nuclear runoff transcription assays showed that hypoxia did not alter the transcription rate of GLUT1. However, hypoxia enhanced the stability of GLUT1 mRNA in neurons ( half-life [t 1 2 ] > 12 hours ) compared with normoxic conditions ( t 1 2 ∼ 10.4 hours ), suggesting the existence of a posttranscriptional mechanism for the regulation of GLUT1 transcript levels. Twenty-four hours of normoxia and 1.0 mmol/L glucose increased neuronal GLUT1 mRNA less than threefold above basal, but 24 hours of glucose and oxygen deprivation increased GLUT1 over 111-fold above basal. Induction of neuronal GLUT1 mRNA was temporally associated with increased levels of GLUT1 protein and with stimulation of intracellular 2-DG accumulation. We conclude that hypoxia reversibly increases the transcript levels of GLUT1 and GLUT3 in rat brain cells and stimulates GLUT1 transcript levels by posttranscriptional mechanisms. Although glucose deprivation alone produces minimal effects on GLUT mRNA levels, hypoxia plus glucose deprivation synergize to markedly increase GLUT gene expression.
Temporal limits of long-range phase discrimination across the visual field

When two flickering sources are far enough apart to avoid low-level motion signals, phase judgment relies on the temporal individuation of the light and dark phases of each source. The highest rate at which the individuation can be maintained has been referred to as Gestalt flicker fusion [Van de Grind, W. A., Grusser, O. -J., & Lunkenheimer, H. U. (1973). Temporal transfer properties of the afferent visual system. Psychophysical, neurophysiological and theoretical investigations. In R. Jung (Ed.), Handbook of sensory physiology (Vol. VII/3, pp. 431-573). Berlin: Springer, Chapter 7] and this has been taken as a measure of the temporal resolution of attention [Verstraten, F. A., Cavanagh, P., & Labianca, A. T. (2000). Limits of attentive tracking reveal temporal properties of attention. Vision Research, 40, 3651-3664; Battelli, L., Cavanagh, P., Intriligator, J., Tramo, M. J., Henaff, M. A., Michel, F., et al. (2001). Unilateral right parietal damage leads to bilateral deficit for high-level motion. Neuron, 32, 985-995]. Here we examine the variation of the temporal resolution of attention across the visual field using phase judgments of widely spaced pairs of flickering dots presented either in the upper or lower visual field and at either 4 degrees or 14 degrees eccentricity. We varied inter-dot separation to determine the spacing at which phase discriminations are no longer facilitated by low-level motion signals. Our data for these long-range phase judgments showed that temporal resolution decreases only slightly with increased distance from center of gaze (decrease from 11.4 to 8.9 Hz between 4 degrees to 14 degrees ), and does not differ between upper and lower visual fields. We conclude that the variation of the temporal limits of visual attention across the visual field differs markedly from that of the spatial resolution of attention.
Do Data Support Nutrition Support? Part I: Intravenous Nutrition

Abstract Intravenous (parenteral) nutrition has been advocated widely as adjunctive care in patients with a variety of underlying diseases. However, the enthusiasm for this therapeutic intervention was based largely on expert opinion. Because the best way to assess the efficacy of any treatment is to test it in a randomized controlled trial, this review will focus on data that was derived from such studies. Using established search strategies, randomized controlled trials were sought that compared one of two forms of intravenous nutrition: parenteral nutrition (nitrogen and ≥10 kcal/kg/day of non-protein calories for ≥5 days) or protein-sparing therapy (nitrogen and fewer non-protein calories) with no type of artificial nutrition beyond regular food and/or standard (5%) dextrose. The randomized controlled trials were stratified by the underlying disease state. The clinical outcomes of interest were mortality, morbidity (total/infectious complications), and/or duration of hospitalization. More than 100 randomized controlled trials failed for the most part to demonstrate that intravenous nutrition had any effect on clinical outcome. There were a few exceptions. In patients undergoing attempted curative surgery for upper gastrointestinal cancer, the use of preoperative parenteral nutrition seemed to reduce the incidence of major postoperative complications. However, this benefit was only found in low-quality randomized controlled trials. Findings conflict regarding the use of parenteral nutrition in patients with acute pancreatitis or undergoing bone marrow transplantation. Parenteral nutrition was harmful when provided to patients undergoing radiation or chemotherapy for cancer. Although no randomized controlled trials exist, it is assumed that parenteral nutrition is useful in patients with an inadequate gastrointestinal tract ("short gut"). Thus, for the most part, randomized controlled trials comparing intravenous nutrition to no artificial nutrition have not shown that this medical intervention is of benefit.
The Constitution and the War Power: What Motivates Congressional Behavior?:

This paper examines whether constitutional interpretations of the proper roles of the executive and the legislative branches influence Congress members’ voting decisions on use of force votes. Specifically, the authors examine the hypothesis that some members are presidentialists—those whose constitutional interpretations favor the executive—and others are congressionalists—those whose constitutional interpretations defend congressional prerogatives. We examined members of Congress who served continuously in either the US House of Representatives or the US Senate from 1990-1999. We identified possible congressionalists and presidentialists using all roll call votes of resolutions to authorize the use of force, and examined floor speeches in the Congressional Record to see how these members explained their votes. We conclude some members of Congress do take constitutional interpretations into account when casting these votes, and justify their actions based upon their reading of the Constitution. Thus, the...
Artificial intelligence scheduling for NASA's Hubble Space Telescope

An artificial intelligence (AI) system called Spike has been implemented for scheduling observations with NASA's Hubble Space Telescope. The system incorporates innovative methodologies for representing and reasoning with scheduling constraints and preferences and for conducting scheduling search. For the former, a combination of constraint satisfaction techniques and weight-of evidence combination has been devised to propagate temporal constraints and preferences. For the latter, a neural network scheduling has been found to be highly efficient. The Spike system is operational and is being used to generate long-range schedules for Space Telescope operations to follow initial on-orbit checkout. >
Selective Permeation of Cross-Linked Polyelectrolyte and Polyelectrolyte-Filled Nonwoven Membranes

Selective permeation, driven by ionic attraction, is one of the most important properties of polyelectrolyte membranes. In this study, selective permeation behaviors of different polyelectrolytes, poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS), poly(styrene sulfonic acid) (PSS), and poly(methacrylic acid) (PMA), were studied via solution-diffusion mechanism. Among these three polyelectrolytes, PSS membranes showed the highest permeabilities for both water and dimethyl methylphophonate vapors due to their high diffusion coefficients caused by the high flexibility of PSS chains. It was also found that the cross-linking of polymer chains increased membrane permeabilities by weakening the physical network formed by ionic attraction. However, the type and cross-linking of polyelectrolytes did not have significant effect on the membrane selectivities. Nonwoven fabric was employed to control the selective permeation of polyelectrolyte membranes. It was found that filling the nonwoven fabric with polyelectrolytes led to composite membranes with reduced permeabilities and increased selectivities. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Staphylococcus aureus colonization before infection is not associated with mortality among S. aureus-infected patients: a meta-analysis.

Background and Objective. The literature is conflicted as to whether people colonized with Staphylococcus aureus are at an increased risk of mortality. The aim of this meta-analysis was to review and analyze the current literature to determine whether prior history of S. aureus colonization is associated with mortality among S. aureus–infected patients.Methods. The PUBMED databases were searched with keywords related to S. aureus colonization and mortality. After reviewing 380 article abstracts and 59 articles in detail, only 7 studies had data on the association between S. aureus colonization and mortality among S. aureus–infected patients. Crude estimates of study odds ratios (ORs) were calculated on the basis of data from subset analyses. We pooled crude ORs from the 7 studies using a random-effects model. Woolf’s test for heterogeneity was assessed.Results. When all studies were pooled in a random-effects model, no association between S. aureus colonization and mortality among S. aureus–infected patie...
Structured sexual therapy with severely dissociative patients

Individuals and couples often have a desire to increase their sexuality even in the face of severe past physical and sexual trauma. Requirements for effective therapy include the establishment of a safe environment, cooperation of a partner to allow the patient to be in control, and an exploration of past sexual abuse to avoid recapitulation that may trigger flashbacks or dissociative episodes. It is also helpful if permission is given to a sexualized ego fragment to become more assertive and help the patient reconcile sexuality as ego-syntonic. The partner needs to develop ability to bring the patient back to the present when dissociating. Clinical examples demonstrate these concepts.
Comparative growth of Palmer amaranth (Amaranthus palmeri) accessions

Abstract A 2-yr field study was conducted to compare growth characteristics of 24 Palmer amaranth accessions collected from across the indigenous range of the species in the United States. Variation in growth and development of Palmer amaranth was noted among accessions based on leaf area ratio (LAR), specific leaf area (SLA), net assimilation rate (NAR), and stem leaf ratio (SLR), but only SLR varied across harvest intervals among accessions. Accessions collected across the range of Palmer amaranth in the United States displayed variation in growth and development based on differences in LAR, SLA, NAR, and SLR. Observed differences among accessions indicate the existence of Palmer amaranth ecotypes. Nomenclature: Palmer amaranth, Amaranthus palmeri (S.) Wats., AMAPA.
Seismic intensities, “size” of earthquakes and related parameters

Abstract The simple model of an earthquake used in Evernden, et al. (1973) was extended to the conterminous United States and observed patterns of isoseismals for major earthquakes studied in relation to the model. Regional attenuation, a known major factor controlling isoseismal patterns, was quantitatively evaluated. Incorporating this regional variation into the model results in the prediction that in terms of energy released, the San Francisco earthquake of 1906 was 50 times as large as Owens Valley 1872 and more than 100 times larger than the Charleston 1886 and New Madrid 1811 earthquakes. All of these were probably of comparable “magnitude”. Other relevant parameters are investigated. Analysis of probability of occurrence of major earthquakes in the Eastern United States suggests average annual return times of intensity X and IX of thousands of years at least. Presently unknown local conditions may lead to much greater probabilities at some localities, and the importance of developing procedures for determining regions of abnormally high risk is stressed.