cssi/SciSciGPT-SciSciNet huggingface dataset:
The ethical dilemma of Thoracic Surgery recertification.

subspecialty practice more important. Clearly, both approaches are considered valid by other Boards and by the ABMS. The current ABTS approach of a comprehensive exam derived from SESATS has been associated with a high pass rate and general approval from diplomates. The ABTS will continue to consider the validity of the two approaches but has also been advised by our psychometrician to gain further experience with the comprehensive exam before considering any change. If undertaken, transition to a modular exam would require a much larger pool of exam questions with subspecialty-focused questions of far greater difficulty than used currently.
Characterization and polymerization of thioacetone

The thioketo and thioenol tautomers of thioacetone have been separated by gas chromatography and characterized by infrared and NMR spectra at low temperatures. The pure thioketo tautomer polymerizes rapidly at room temperature, but the thioenol tautomer does not. At room temperature, the thioenol gradually disappears, probably by tautomerization to the reactive thioketo form, which then polymerizes. Attempts to copolymerize thioacetone with vinyl and diene monomers were not successful.
The managerial limit to the growth of Firms revisited

The Penrose Hypothesis that managerial resources will grow at a rate somewhat faster than that of firm size is tested along with the alternative steady-state hypothesis that both grow at the same rate. A dynamic firm model is used to motivate the study. U.S. Department of Labor, Bureau of Labor Statistics' Occupational Employment Statistics are used to measure managerial resources. Firm size is in terms of employment, or real value added, or real value of shipments. The data cover the period 2003–2006 and are used with a Cobb-Douglas type log-form growth function. The statistical results are quite strongly in favor of the Penrose Hypothesis, suggesting a managerial limit to the rate of growth of the firm. Copyright © 2010 John Wiley & Sons, Ltd.
The Role of Higher-Order SPOP Oligomers for Localization to Cellular “Bodies” and Ubiquitination Activity

Light microscopically detectable, non-membrane bound cellular “bodies” are large protein assemblies with liquid-like properties, but the biophysical basis of their formation is unclear. Weak, multivalent protein interactions can result in higher-order complexes and can enable the formation of cellular bodies. The inherent size heterogeneity of higher-order complexes renders them difficult to characterize biophysically. As a result, their size distributions remain largely unquantified, limiting molecular insight into their biological functions. We report a novel mechanism governing cellular body formation of the Speckle-type POZ protein (SPOP), which was recently identified as tumor suppressor, is a ubiquitin ligase substrate adaptor that localizes to nuclear puncta. We demonstrate that its cellular localization is dependent upon the ability of SPOP to form higher-order homo-oligomers through indefinite self-association, mediated by two distinct oligomerization domains. Furthermore, in vitro ubiquitination of substrates is enhanced through higher-order self-association of SPOP, suggesting that SPOP puncta are hotspots of substrate ubiquitination. One of SPOP's domains dimerizes with nanomolar affinity yielding stable SPOP dimers as “building blocks” for indefinite self-association, while the other domain dimerizes with micromolar affinity, rendering SPOP oligomers highly dynamic. Together, this results in isodesmic self-association, in which each addition of a dimer occurs with the same affinity, independent of the oligomer size. From this model, we describe the size distribution of SPOP oligomers, providing for the first time a quantitative analysis of protein assemblies participating in the formation of cellular bodies. Mutations within both oligomerization domains have been observed in a variety of cancers, supporting our conclusion that SPOP self-association is important for its biological function. We propose that dynamic, higher-order protein self-association is a general mechanism underlying the formation of cellular bodies, which may serve as switches to fine-tune signaling cascades.
High Grade Glioma Mimicking Voltage Gated Potassium Channel Complex Associated Antibody Limbic Encephalitis

Though raised titres of voltage gated potassium channel (VGKC) complex antibodies have been occasionally associated with extracranial tumours, mainly presenting as Morvan's Syndrome or neuromyotonia, they have not yet been reported to be associated with an intracranial malignancy. This is especially important as misdiagnosis of these conditions and delay of the appropriate treatment can have important prognostic implications. We describe a patient with a high grade glioma presenting with clinical, radiological, and serological features consistent with the diagnosis of VGKC antibody associated limbic encephalitis (LE). This is the first association between a primary brain tumour and high titre of VGKC complex antibodies. Clinicoradiological progression despite effective immunosuppressive treatment should prompt clinicians to look for alternative diagnoses. Further studies to elucidate a possible association between VGKC complex and other surface antigen antibodies with primary brain tumours should be carried out.
Characterization of free subunits of ribulose-1,5-bisphosphate carboxylase

Abstract Free subunits of ribulose-1,5-bisphosphate carboxylase (RubPcase) labeled in vivo, and separated from the holoenzyme on sucrose gradients, have been characterized as follows: [ 35 S]methionine label in each of the free subunit pools is chased slowly by either the endogenous or exogenously supplied amino acid. The small subunit pool consists of monomers, while the large subunit pool consists largely of dimers. It is possible that these subunits, or trace amounts of other aggregates, may be intermediates in RubPcase assembly.
Cherubism: Diagnosis, treatment, and comparison with central giant cell granulomas and giant cell tumors

An extensive case of cherubism in a 17-year-old girl with no apparent familial history is presented. The rationale for treatment is presented and is compared with previous reports that have advocated nontreatment. The clinical and histologic similarities of cherubism to central giant cell granuloma and the giant cell tumor of bone are also discussed.
CHARACTERIZATION OF EXTRACELLULAR BACTERIAL ENZYMES WHICH DEPOLYMERIZE A SOLUBLE LIGNITE COAL POLYMER

Abstract Several Gram negative and positive soil bacteria, isolated by an enrichment technique in a liquid minimal medium containing water-soluble lignite coal polymer as a sole source of carbon and energy, were screened for their abilities to depolymerize coal when growing in peptone broth containing soluble coal. One Gram positive and three Gram negative strains significantly depolymerized the coal within 3–6 days. These strains were screened for the production of extracellular coal depolymerizing enzymes. Each bacterium, including Gram negative strains DLC-BB2, DLC-62 and DLC-63/9, and Gram positive strain DLC-21, produced lignite depolymerizing enzymes. Extracellular filtrates from 3-day cultures grown in peptone medium supplemented with an inducing level of soluble coal polymer, contained an enzymatic activity which caused significant depolymerization of the coal polymer after 4 h of incubation of enzyme with coal (30 °C), as shown by high performance liquid chromatography (h.p.l.c.). Each bacterium produced similarly acting enzymes which progressively converted the principal broad coal polymer peak of about MW 174000 into a much sharper peak of about 113000. In some cases, even lower molecular weight products appeared upon prolonged incubation of the reaction mixtures. The activities were inactivated by boiling of culture supernatants. While chemical analyses of enzymatically depolymerized coal products indicated that the depolymerization was non-oxidative, the specific type(s) of enzymes involved in the depolymerization remain to be identified. The results show that non-oxidative, enzymatic depolymerization of coal is possible.
The pentose shunt in wild‐type and glucose‐6‐phosphate dehydrogenase deficient Drosophila melanogaster

Four-day old Drosophila melanogaster homozygous or hemizygous for the glucose-6-phosphate dehydrogenase mutant allele, Zw−, possess slightly less than 10% as much glucose-6-phosphate dehydrogenase activity in whole-fly homogenates as their wild-type, Zw+, counterparts. The reduction of glucose-6-phosphate dehydrogenase activity in Zw− adults had no effect upon 6-phosphogluconate dehydrogenase, phosphofructokinase, or malic enzyme activities. However, activities of the non-oxidative pentose shunt enzymes were significantly greater in Zw− adults than in Zw+ adults. Radiotracer procedures indicate that the oxidative phase of the pentose shunt is blocked in Zw− adults. Zw− larvae grow less well on a defined minimal amino acid diet lacking fatty acids and whole nucleic acid than do Zw+ larvae, indicating that Zw− individuals have a lower biosynthetic capacity than Zw+ individuals.
OPTIMUM DILUTION PROFILES OF COMPOSITE ZEOLITES IN PACKED BEDS

Abstract The paper examines theoretically the conversion of methanol over composite zeolite spherical catalytic particles in a fixed bed reactor. The composite zeolite contains small zeolite particles uniformly distributed in an amorphous silica-alumina matrix. Two problems are considered. The first is concerned with the effect of dilution of the catalyst with amorphous silica-alumina on the concentrations of species and temperature along the bed. Isothermal and nonisothermal pellets are considered. The second is concerned with the calculation of the optimum dilution profile which maximizes the rate of consumption of methanol.
Effects of the tol mutation on allelic interactions at het loci in Neurospora crassa.

A mutant at the tol locus of Neurospora crassa can suppress heterokaryon (vegetative) incompatibility associated with differences at the mating-type locus. We tested the ability of this allele to suppress the vegetative incompatibility reactions that can occur when strains differ at one of nine het loci (het-C, -D, -E, -5, -6, -7, -8, -9, and -10). We found no cases in which the tol mutant suppresses a heteroallelic het locus interaction. Thus, the interaction(s) that leads to vegetative incompatibility because of differences at the mating-type locus is distinct from the interaction(s) that leads to vegetative incompatibility because of differences at any of these nine het loci.Key words: heterokaryon, mating type, vegetative compatibility.
An actigraphy study of sleep and pain in midlife women: the Study of Women's Health Across the Nation Sleep Study

Objective We examined whether women reporting nighttime pain would have more actigraphy-measured evidence for disturbed sleep and would report feeling less rested compared with women without nighttime pain. Methods Up to 27 consecutive nights of actigraphy and sleep diary data from each participant were analyzed in this community-based study of 314 African-American (n = 118), white (n = 141), and Chinese (n = 55) women, aged 48 to 58 years, who were premenopausal, perimenopausal, or postmenopausal and were participating in the Study of Women's Health Across the Nation Sleep Study. Dependent variables were actigraphy-measured movement and fragmentation index, total sleep time, sleep efficiency, and diary self-report of "feeling rested" after waking up. All outcomes were fitted using linear mixed-effects models to examine covariate-adjusted associations between the independent variable (nighttime pain severity) and sleep outcomes. Results Higher pain severity scores were associated with longer sleep duration but reduced sleep efficiency and less restful sleep. Women reporting nocturnal vasomotor symptoms had more sleep-related movement and sleep fragmentation, had reduced sleep efficiency, and were less likely to feel rested after wakening whether or not they reported pain. Conclusions Midlife women who report higher nighttime pain levels have more objective evidence for less efficient sleep, consistent with self-reported less restful sleep. Nocturnal vasomotor symptoms also can contribute to restlessness and wakefulness in midlife women.
Myocardial perfusion and angiographic correlations in patients with ST-segment elevation during dobutamine stress perfusion imaging

Background There is scanty information on the angiographic and myocardial perfusion correlates of dobutamine-induced ST-segment elevation.
Canaries in the coalmine: On the measurement and correlates of organizational threat recognition

This research expands the job performance domain by introducing organizational threat recognition as a meaningful criterion construct. Threat recognition is conceptualized as consisting of two separate aspects of behaviour—detecting and expressing workplace or organizational threats. To assess these dimensions, we developed two, six-item measures and had 244 workers respond to these items and to a series of individual difference measures. Psychometric results, including exploratory and confirmatory factor analyses, supported the a priori factor structure of these measures and indicated that these dimensions are distinguishable from each other and from task performance. Furthermore, correlations involving the individual difference variables revealed that several of these variables including positive affectivity, job tenure, and affective commitment were more strongly related to the threat dimensions than to task performance.
Genetic isolation and morphological divergence mediated by high-energy rapids in two cichlid genera from the lower Congo rapids

It is hypothesized that one of the mechanisms promoting diversification in cichlid fishes in the African Great Lakes has been the well-documented pattern of philopatry along shoreline habitats leading to high levels of genetic isolation among populations. However lake habitats are not the only centers of cichlid biodiversity - certain African rivers also contain large numbers of narrowly endemic species. Patterns of isolation and divergence in these systems have tended to be overlooked and are not well understood. We examined genetic and morphological divergence among populations of two narrowly endemic cichlid species, Teleogramma depressum and Lamprologus tigripictilis, from a 100 km stretch of the lower Congo River using both nDNA microsatellites and mtDNA markers along with coordinate-based morphological techniques. In L. tigripictilis, the strongest genetic break was concordant with measurable phenotypic divergence but no morphological disjunction was detected for T. depressum despite significant differentiation at mtDNA and nDNA microsatellite markers. The genetic markers revealed patterns of philopatry and estimates of genetic isolation that are among the highest reported for any African cichlid species over a comparable geographic scale. We hypothesize that the high levels of philopatry observed are generated and maintained by the extreme hydrology of the lower Congo River.
Homoanomeric effects in six-membered heterocycles.

Structural and energetic consequences of homoanomeric n(X) → β-σ*(C−Y) interactions in saturated six-membered heterocycles where X = O, N, S, Se and Y = H, Cl were studied computationally using a combination of density functional theory (B3LYP) and Natural Bond Orbital (NBO) analysis. Unlike the classic anomeric effect where the interacting donor and acceptor orbitals are parallel and overlap sidewise in a π-fashion, orbital interactions responsible for homoanomeric effects can follow different patterns imposed by the geometric restraints of the respective cyclic moieties. For the equatorial β-C−Y bonds in oxa-, thia- and selena-cyclohexanes, only the homoanomeric n(X)ax → σ*(C−Y)eq interaction (the Plough effect) with the axial lone pair of X is important, whereas the n(X)eq → σ*(C−Y)eq interaction (the W-effect) is negligible. On the other hand, the W-effect is noticeably larger than the n(X)ax → σ*(C−Y)eq interaction in azacyclohexanes. Hyperconjugation is a controlling factor which determines relative...
Synthetic aperture holography: a novel approach to three-dimensional displays

We describe an electro-optic apparatus capable of displaying a computer-generated hologram in real time. The computer-generated hologram is calculated by a supercomputer, read from a fast frame buffer, and transmitted to a wide-bandwidth acousto-optic modulator. Coherent light is modulated by the acousto-optic modulator and optically processed to produce a three-dimensional image with horizontal parallax. We evaluate different display geometries and their effect on the optical parameters of the system. We then show how the display resolution can be increased by simultaneously writing three acoustic columns on a single crystal and optically multiplexing the resulting holograms. We finally describe some improvements that follow from the analysis.
Nonlinear atom optics: General formalism and atomic solitons

We present a many-body theory of nonlinear atom optics, and discuss some of its physical implications in the coherent regime. Considering a system of N identical two-level atoms interacting with classical and quantum-mechanical electromagnetic fields, we derive a Fock-space many-particle master equation. Introducting a Bogoliubov-Born-Green-Kirkwood-Yvon hierarchy and a Hartree-Fock factorization to truncate this hierarchy, we obtain an effective nonlinear single-particle master equation that forms the basis of nonlinear atom optics. In the second part of the paper, we concentrate on the coherent part of that master equation, and derive an effective single-atom nonlinear Schr\"odinger equation. This equation leads to the prediction of a number of effects, and, in particular, several kinds of atomic solitons. We discuss and numerically study two such kinds of solitons, Thirring solitons and gap solitons. Finally, the axial containment of an atomic gap soliton is illustrated.
Patient–ventilator interaction: A general model for nonpassive mechanical ventilation

A general mathematical model for the dynamic behaviour of a single-compartment respiratory system in response to an arbitrary applied inspiratory airway pressure and arbitrary respiratory muscle activity is investigated. The model is used to compute explicit expressions for ventilation and pressure variables of clinical interest for clinician-selected and impedance-determined inputs. The outcome variables include tidal volume, end-expiratory pressure, minute ventilation, mean alveolar pressure, average pleural pressure, as well as the work performed by the ventilator and the respiratory muscles. It is also demonstrated that under suitable conditions, there is a flow reversal that can occur during inspiration.
Animal on a chip: a microscale cell culture analog device for evaluating toxicological and pharmacological profiles

With the increasing rate of discovery of new potential pharmaceuticals, an accurate high throughput screening method is needed to provide toxicology and pharmcology profiles of chemicals. This can be done using a cell culture analog device which uses interconnected tissue cultures to represent different organ systems in animals. A working prototype of microscale cell culture analog (CCA) device has been constructed. Cells cultured in the system have been shown to be viable for more than 24 hours. In this paper, we will present the development of this microscale CCA device as well as the integratable micropump we have created to produce the recirculating flow.
The Unintended Effects of a Ban on Sex-Selective Abortion on Infant Mortality: Evidence from India

India has long struggled with persistent problems of sex-selective abortions and the neglect of female children. In 1996, the Pre-Natal Diagnostics Techniques Act was implemented to stop the practices of prenatal sex determination and selective abortions. This paper examines whether the law has been effective in reducing gender imbalance, and in turn potentially exacerbated post-natal discrimination against newborn girls. Using retrospective birth history data from the Indian District Level Household Survey (2002–2004), we exploit a natural experiment involving a variation in the timing of the law across states. We analyse the differential impact of the law on newborn sex ratios and infant mortality rates. Our findings indicate that the law significantly increased the likelihood of a female birth, improving female-to-male sex ratios at birth. We also find that it was generally associated with no change in the relative mortality of infant girls.
On the nonsingular submatrices of the incidence matrix of a graph over the real field

Abstract The nonsingular submatrices of maximum order of the complete and the reduced incidence matrices over the real field of a graph are shown to be in one-to-one correspondence with the odd generalized circuits and the odd generalized k-trees of the graph, respectively. It is also shown that the positive terms in the final expansions of a unisignant and its cofactors correspond to these subgraphs. Thus, a technique for enumerating all the positive terms without duplication is obtained. The extension to digraphs is also considered, and illustrative examples are given.
Africa And U.S. Foreign Policy: Contributions of the Diaspora to Democratic African Leadership

This article is an assessment of the role of African Americans in effecting democratic African politics and leadership. Assessments of African development provide the basis for explaining African contemporary leadership challenges and a survey of U.S. foreign policy toward Africa is used to evaluate the domestic political environment that elicited African Americans’ political activism on behalf of Africa. Two historic case studies, of Italy’s invasion of Ethiopia in 1935 and the anti-apartheid struggle in South Africa during the 1980s, are used to identify, characterize, and assess African Americans’ political influence on African development and leadership. The article assesses the means, motivation, and impact of African American political activity on behalf of Africa to explain how democratic movements may improve African leadership. The article concludes that African Americans most effectively contribute to democratic development in Africa when they interact directly with African social and political ...
Target reflectance measurements for calibration of lidar atmospheric backscatter data.

Wavelength and angular dependence of reflectances and depolarization in the 9-11 micron region are reported for four standard targets: flowers of sulfur, flame-sprayed aluminum, 20-grit sandblasted aluminum, and 400-grit silicon carbon sandpaper. Measurements are presented and compared using a CW CO2 grating-tunable laser in a laboratory backscatter apparatus, an integrating sphere, and a coherent pulsed TEA-CO2 lidar system operating in the 9-11 micron region. Reflectance theory related to the use of hard targets to calibrate lidar atmospheric backscatter data is discussed.
Polymer-mediated DNA vaccine delivery via bystander cells requires a proper balance between transfection efficiency and cytotoxicity

Direct targeting of dendritic cells is an ideal goal for DNA vaccine delivery in order to stimulate both arms of the immune system. However, dendritic cells are often difficult to transfect using nonviral polyplexes. Here we show that transfecting bystander cells such as fibroblasts with PEI/DNA complexes leads to efficient cross-presentation of a model antigen by dendritic cells and subsequent activation of antigen-specific CD8+ T cells. Maturation of dendritic cells is also stimulated after co-culture with transfected fibroblasts. Such outcomes depend on a proper balance between transfection efficiency and polyplex-induced cytotoxicity in the fibroblasts. In fact, substantial cytotoxicity is desirable and even necessary for cross-presentation and cross-priming of T cells. This study illustrates a new pathway of polymer-based DNA vaccine delivery via bystander cells without direct targeting of antigen-presenting cells and highlights the importance of exploiting polymer-induced cytotoxicity for the benefit of immune activation.
Learning to Detect Moving Shadows in Dynamic Environments

We propose a novel adaptive technique for detecting moving shadows and distinguishing them from moving objects in video sequences. Most methods for detecting shadows work in a static setting with significant human input. To remove these limitations, we propose a more general semi-supervised learning technique to tackle the problem. First, we exploit characteristic differences in color and edges in the video frames to come up with a set of features useful for classification. Second, we use a learning technique that employs Support Vector Machines and the Co-training algorithm, that relies on a small set of human-labeled data. We observe a surprising phenomenon that Co-training can counter the effects of changing underlying probability distributions in the feature space. From the standpoint of detecting shadows, once deployed, the proposed method can dynamically adapt to varying conditions without any manual intervention, and performs better classification than previous methods on static and dynamic environments alike. The strengths of the proposed technique are the small quantity of human labeled data required, and the ability to adapt automatically to changing scene conditions.
Metabolites in Safety Testing: “MIST” for the Clinical Pharmacologist

To address questions relating to the safety assessment of circulating drug metabolites in humans, the US Food and Drug Administration (FDA) and the International Conference on Harmonisation (ICH) have recently issued regulatory guidances1,2 that effectively require metabolite profiling in humans during early clinical development of a candidate drug. The clinical metabolite profiling results may require separate safety assessment studies in humans of stable circulating metabolites if such metabolites are not formed in sufficient concentrations in the plasma during nonclinical safety assessment of the parent drug. Clinical Pharmacology & Therapeutics (2010) 87 3, 345–350. doi:10.1038/clpt.2009.283
Use of echocardiography for the phenotypic assessment of genetically altered mice.

Transgenic mice displaying abnormalities in cardiac development and function represent a powerful new tool for understanding molecular mechanisms underlying normal cardiovascular function and the p...
Metabolic alkalosis, bedside and bench.

Although significant contributions to the understanding of metabolic alkalosis have been made recently, much of our knowledge rests on data from clearance studies performed in humans and animals many years ago. This article reviews the contributions of these studies, as well as more recent work relating to the control of renal acid-base transport by mineralocorticoid hormones, angiotensin, endothelin, nitric oxide, and pottasium balance. Finally, clinical aspects of metabolic alkalosis are considered.
Treatment of schizophrenia: preventing the progression of disease

Atypical antipsychotic drugs offer a number of advantages compared with typical antipsychotic drugs during the acute treatment of psychotic episodes and maintenance treatment to prevent psychotic relapses in patients with schizophrenia. These advantages include superior efficacy, especially for negative symptoms and reduced extrapyramidal adverse effects. Clinicians, however, need to be vigilant regarding new adverse effects that may be more strongly associated with atypical than typical drugs, especially those related to weight gain. Despite increased pill costs for atypical antipsychotic drugs, the overall costs of providing care to patients with schizophrenia using these drugs do not appear to be substantially higher.
Congenital heart disease: Measuring physiology with MRI

Summary Cine MRI and VEC MRI can be used to quantitate the physiology of the heart and great vessels in patients with CHD. This information can be a valuable adjunct to anatomical imaging for preoperative planning as well as postoperative monitoring. Some important clinical applications of quantitative cardiovascular functional MRI include measurement of ventricular masses, stroke volumes, and ejection fractions; estimation of shunts and valvular regurgitation; assessment of collateral blood flow and pressure gradients in aortic coarctation; and postsurgical evaluation of conduit blood flow and pressure gradients.
VMM-based hidden process detection and identification using Lycosid

Use of stealth rootkit techniques to hide long-lived malicious processes is a current and alarming security issue. In this paper, we describe, implement, and evaluate a novel VMM-based hidden process detection and identification service called Lycosid that is based on the cross-view validation principle. Like previous VMM-based security services, Lycosid benefits from its protected location. In contrast top revious VMM-based hidden process detectors, Lycosid obtains guest process information implicitly. Using implicit information reduces its susceptibility to guest evasion attacks and decouples it from specific guest operating system versions and patch levels. The implicit information Lycosid depends on, however, can be noisy and unreliable. Statistical inference techniques like hypothesis testing and line arregression allow Lycosid to trade time for accuracy. Despite low quality inputs, Lycosid provides a robust, highly accurate service usable even insecurity environments where the consequences for wrong decisions can behig.
Comparison of Radar Backscatter from Antarctic and Arctic Sea Ice

Two ship-based step-frequency radars, one at C-band (5.3 GHz) and one at Ku-band (13.9 GHz), measured backscatter from ice in the Weddell Sea. Most of the backscatter data were from first-year (FY) and second-year (SY) ice at the ice stations where the ship was stationary and detailed snow and ice characterizations were performed. The presence of a slush layer at the snow-ice interface masks the distinction between FY and SY ice in the Weddell Sea, whereas in the Arctic the separation is quite distinct. The effect of snow-covered ice on backscattering coefficients (sigma0) from the Weddell Sea region indicates that surface scattering is the dominant factor. Measured sigma0 values were compared with Kirchhoff and regression-analysis models. The Weibull power-density function was used to fit the measured backscattering coefficients at 45 deg.
Aversion for case reporting by major medical journals: A trend towards perfect dichotomy

Introduction: This case report introduces the traditional form of medical literature. It chronicles the contributions made by landmark case reports in the times of old as well as in the present. Review: The author details the current case report publishing-aversion by major medical journals, and attempts to explain the rationale. The article describes the impact of evidencebased medicine and journal impact factor protection as facilitators of the “discrimination” against case reporting. The paper analyzes the case report acceptance policy of 20 medical journals across the whole spectrum of impact factors and identifies interesting patterns. The author chronicles the proliferation of case reporting journals and identifies the trend towards a perfect dichotomy in medical publishing. Conclusion: In concluding, the author gives his take on the many issues raised while proposing potential solutions.
Cleaning during Initial Stages of Epitaxial Growth in an Ultrahigh Vacuum Rapid Thermal Chemical Vapor Deposition Reactor

In this paper, we report our results on surface preparation for the growth of epitaxial Si films. Hydrogen passivated surfaces are currently being investigated for application in Si epitaxy to eliminate the high temperature in-situ bake necessary to remove the native oxide. Hydrogen passivation is obtained by a dilute HF dip before the substrate is loaded in the process chamber. However the passivation is partially lost when the HF dip is followed by a water rinse which results in oxygen absorption on the substrate. It was found that the peak oxygen concentration at the epitaxy substrate interface increase by an order of magnitude due to a five minute water rinse. We report here that oxygen and carbon at the epitaxy substrate interface can be desorbed during initial stage of epitaxial growth by reducing epitaxial growth rate. In this work, epitaxial Si films were deposited over a wide range of growth rates obtained by varying Si 2 H 6 flow rates. The peak oxygen concentration decreases by an order of magnitude by changing the growth rate from 3000 to 700A/kminute for a deposition temperature of 800°C. We believe that at higher growth rates Si overgrows on absorbed oxygen maintaining epitaxial alignment reflected in the good electrical quality of the epitaxial films. However, at low growth rates oxygen has sufficient time to desorb before overgrowth can take place, improving the epitaxy substrate interface quality.
Proteome profiling for assessing diversity: analysis of individual heads of Drosophila melanogaster using LC-ion mobility-MS.

The proteomes of three heads of individual Drosophila melanogaster organisms have been analyzed and compared by a combination of liquid chromatography, ion mobility spectrometry, and mass spectrometry approaches. In total, 197 proteins are identified among all three individuals (an average of 120 ( 20 proteins per individual), of which at least 101 proteins are present in all three individuals. Within all three datasets, more than 25 000 molecular ions (an average of 9000 ( 2000 per individual) corresponding to protonated precursor ions of individual peptides have been observed. A comparison of peaks among the datasets reveals that peaks corresponding to protonated peptides that are found in all heads are more intense than those features that appear between pairs of or within only one of the individuals. Moreover, there is little variability in the relative intensities of the peaks common among all individuals. It appears that it is the lower abundance components of the proteome that play the most significant role in determining unique features of individuals.
The Parsimony Ratchet, a New Method for Rapid Parsimony Analysis

The Parsimony Ratchet1 is presented as a new method for analysis of large data sets. The method can be easily implemented with existing phylogenetic software by generating batch command files. Such an approach has been implemented in the programs DADA (Nixon, 1998) and Winclada (Nixon, 1999). The Parsimony Ratchet has also been implemented in the most recent versions of NONA (Goloboff, 1998). These implementations of the ratchet use the following steps: (1) Generate a starting tree (e.g., a “Wagner” tree followed by some level of branch swapping or not). (2) Randomly select a subset of characters, each of which is given additional weight (e.g., add 1 to the weight of each selected character). (3) Perform branch swapping (e.g., “branch-breaking” or TBR) on the current tree using the reweighted matrix, keeping only one (or few) tree. (4) Set all weights for the characters to the “original” weights (typically, equal weights). (5) Perform branch swapping (e.g., branch-breaking or TBR) on the current tree (from step 3) holding one (or few) tree. (6) Return to step 2. Steps 2–6 are considered to be one iteration, and typically, 50–200 or more iterations are performed. The number of characters to be sampled for reweighting in step 2 is determined by the user; I have found that between 5 and 25% of the characters provide good results in most cases. The performance of the ratchet for large data sets is outstanding, and the results of analyses of the 500 taxon seed plant rbcL data set (Chase et al., 1993) are presented here. A separate analysis of a three-gene data set for 567 taxa will be presented elsewhere (Soltis et al., in preparation) demonstrating the same extraordinary power. With the 500-taxon data set, shortest trees are typically found within 22 h (four runs of 200 iterations) on a 200-MHz Pentium Pro. These analyses indicate efficiency increases of 20×–80× over “traditional methods” such as varying taxon order randomly and holding few trees, followed by more complete analyses of the best trees found, and thousands of times faster than nonstrategic searches with PAUP. Because the ratchet samples many tree islands with fewer trees from each island, it provides much more accurate estimates of the “true” consensus than collecting many trees from few islands. With the ratchet, Goloboff's NONA, and existing computer hardware, data sets that were previously intractable or required months or years of analysis with PAUP* can now be adequately analyzed in a few hours or days.
Chemotherapy refractory testicular germ cell tumor is associated with a variant in Armadillo Repeat gene deleted in Velco-Cardio-Facial syndrome (ARVCF).

Introduction: There is evidence that inherited genetic variation affects both testicular germ cell tumor (TGCT) treatment outcome and risks of late-complications arising from cisplatin-based chemotherapy. Using a candidate gene approach, we examined associations of three genes involved in the cisplatin metabolism pathway, GSTP1, COMT, and TPMT, with TGCT outcome and cisplatin-induced neurotoxicity. Material and Methods: Our study population includes a subset of patients (n=137) from a genome-wide association study at the University of Pennsylvania that evaluates inherited genetic susceptibility to TGCT. All patients in our study had at least one course of cisplatin-based chemotherapy with at least one year of follow up. A total of 90 markers in GSTP1, COMT and TPMT and their adjacent genomic regions (± 20 kb) were analyzed for associations with refractory TGCT after first course of chemotherapy, progression-free survival (PFS), overall survival (OS), peripheral neuropathy, and ototoxicity. Results: After adjustment for multiple comparisons, one SNP, rs2073743, in the flanking region (± 20 kb) of COMT was associated with refractory TGCT after initial chemotherapy. This SNP lies within the intron region of the Armadillo Repeat gene deleted in Velco-Cardio-Facial syndrome (ARVCF). The G allele of rs2073743 predisposed patients to refractory disease with a relative risk of 2.6 (95% CI 1.1, 6.3; P=0.03). Assuming recessive inheritance, patients with the GG genotype had 22.7 times higher risk (95% CI 3.3, 155.8; P=0.04) of developing refractory disease when compared to those with the GC or CC genotypes. We found no association of our candidate genes with peripheral neuropathy, ototoxicity, PFS and OS. Discussion: This is the first study to suggest that germline genetic variants of ARVCF may affect TGCT outcome. The result of this study is hypothesis generating and should be validated in future studies.
Synaptic Heterogeneity and Stimulus-Induced Modulation of Depression in Central Synapses

Short-term plasticity is a pervasive feature of synapses. Synapses exhibit many forms of plasticity operating over a range of time scales. We develop an optimization method that allows rapid characterization of synapses with multiple time scales of facilitation and depression. Investigation of paired neurons that are postsynaptic to the same identified interneuron in the buccal ganglion of Aplysia reveals that the responses of the two neurons differ in the magnitude of synaptic depression. Also, for single neurons, prolonged stimulation of the presynaptic neuron causes stimulus-induced increases in the early phase of synaptic depression. These observations can be described by a model that incorporates two availability factors, e.g., depletable vesicle pools or desensitizing receptor populations, with different time courses of recovery, and a single facilitation component. This model accurately predicts the responses to novel stimuli. The source of synaptic heterogeneity is identified with variations in the relative sizes of the two availability factors, and the stimulus-induced decrement in the early synaptic response is explained by a slowing of the recovery rate of one of the availability factors. The synaptic heterogeneity and stimulus-induced modifications in synaptic depression observed here emphasize that synaptic efficacy depends on both the individual properties of synapses and their past history.
In vivo D2 dopamine receptor density in psychotic and nonpsychotic patients with bipolar disorder.

Background: A prior positron emission tomographic study from The Johns Hopkins University, Baltimore, Md, usingN-methylspiperone labeled with carbon 11 reported elevated basal ganglia D2dopamine receptor density (Bmax) values in neuroleptic-naive schizophrenic patients compared with controls. We have now extended these studies to include patients with bipolar disorder. Methods: Patients with bipolar disorder (n=14) either had never received neuroleptic medication or had been neuroleptic-free for more than 6 months, and they metDSM-IIIcriteria for currently symptomatic affective disorder. Patients with bipolar disorder were compared with matched schizophrenic patients and normal controls. All received two positron emission tomographic scans, the second of which was preceded by oral administration of haloperidol lactate, to permit the calculation of D2dopamine receptor Bmax. Results: Diagnostic groups differed in Bmaxby analysis of variance (P Conclusions: We conclude that, like schizoprenic patients, patients with psychotic bipolar disorder have elevations of D2dopamine receptor Bmaxvalues and that such elevations in affective disorder are more closely associated with the presence of psychosis than with mood abnormality. Elevations in dopamine receptor values thus may occur in psychiatric states that are characterized by psychotic symptoms rather than being specific to schizophrenia.
Climate system response to stratospheric ozone depletion and recovery

We review what is presently known about the climate system response to stratospheric ozone depletion and its projected recovery, focusing on the responses of the atmosphere, ocean and cryosphere. Compared with well-mixed greenhouse gases (GHGs), the radiative forcing of climate due to observed stratospheric ozone loss is very small: in spite of this, recent trends in stratospheric ozone have caused profound changes in the Southern Hemisphere (SH) climate system, primarily by altering the tropospheric midlatitude jet, which is commonly described as a change in the Southern Annular Mode. Ozone depletion in the late twentieth century was the primary driver of the observed poleward shift of the jet during summer, which has been linked to changes in tropospheric and surface temperatures, clouds and cloud radiative effects, and precipitation at both middle and low latitudes. It is emphasized, however, that not all aspects of the SH climate response to stratospheric ozone forcing can be understood in terms of changes in the midlatitude jet. The response of the Southern Ocean and sea ice to ozone depletion is currently a matter of debate. For the former, the debate is centred on the role of ocean eddies in possibly opposing wind-driven changes in the mean circulation. For the latter, the issue is reconciling the observed expansion of Antarctic sea-ice extent during the satellite era with robust modelling evidence that the ice should melt as a result of stratospheric ozone depletion (and increases in GHGs). Despite lingering uncertainties, it has become clear that ozone depletion has been instrumental in driving SH climate change in recent decades. Similarly, ozone recovery will figure prominently in future climate change, with its impacts expected to largely cancel the impacts of increasing GHGs during the next half-century.
Oviposition Site Selection by the Spotted Lady Beetle Coleomegilla maculata (Coleoptera: Coccinellidae): Choices Among Plant Species

Abstract The polyphagous lady beetle Coleomegilla maculata (DeGeer) was previously shown to oviposit more frequently on the weed, Acalypha ostryaefolia Riddell, than on sweet corn, Zea mays L. In that earlier study, the presence of A. ostryaefolia led to higher densities of C. maculata larvae on nearby corn. To determine if C. maculata’s apparent oviposition preference for A. ostryaefolia was limited to that weed species, we conducted a 2-yr field study using A. ostryaefolia along with eight other common broadleaf annual weeds. A separate field experiment compared oviposition on just A. ostryaefolia and the weed Abutilon theophrasti Medicus. The possible influence of whitefly Trialeurodes abutiloneus (Haldeman) presence on C. maculata oviposition site selection also was examined. When nine weed species were available, significant oviposition preference was found for A. theophrasti. Similarly, far more egg clusters were found on A. theophrasti than on A. ostryaefolia when only those two species were availa...
Utilization of algae blooms as a source of natural fibers for biocomposite materials: Study of morphology and mechanical performance of Lyngbya fibers

Abstract Algae blooms represent a worldwide contamination problem, 55% of the water bodies in the U.S. are in poor condition mainly because of algae. A second source of algae waste is the co-product of the algae biofuel process. There is potentially an abundant source of algae fiber; however, little is known about the utilization of algae as reinforcement for natural fiber composites (NFC). The purpose of this work is to study the morphology and mechanical properties of the blue-green algae Lyngbya as a natural fiber reinforcement for biocomposite materials according to the Standards ASTM-D792-00 and ASTM C1557-03. Lyngbya were sourced and by conducting a sequence of chemical treatments on the algae the fiber that was extracted. The average properties of Lyngbya fiber are: density 1.06 g/cm3, width 60 μm, tensile strength of 215 MPa, and tensile modulus of 24 GPa. Lyngbya fiber properties are comparable to jute and sisal fibers.
A Genetic Programming Approach to Design Resource Allocation Policies for Heterogeneous Workflows in the Cloud

When dealing with very large applications in the cloud, higher costs do not always result in better turnaround times, particularly for complex workflows with multiple task dependencies. Thus, resource allocation policies are needed that can determine when using expensive but faster resources is best and when it is not. Manually developing such heuristics is time consuming and limited by the subjective beliefs of the developer. To overcome such impediments, we present an automatic method that designs and evaluates a large set of policies using a genetic programming approach. Our method finds a robust set of policies that adapt to changes in workload while using resources efficiently. Our results show that our genetic programming designed policies perform better than greedy and other human designed policies do.
Parental Presence at the Bedside of a Child with Suspected Ebola: An Expert Discussion

The Ebola virus disease (Ebola) outbreak in West Africa (2014-2015) prompted domestic planning to address the scenario in which a traveler imports Ebola into the United States. Parental presence at the bedside of a child with suspected or confirmed Ebola emerged as a challenging issue for pediatric health care providers and public health practitioners. At the heart of the issue was the balance of family-centered care and appropriate infection control, which are not easily aligned in the setting of Ebola. In the following dialogue, pediatricians, who participated in discussions about parental presence during the evaluation of pediatric persons under investigation, and a public health ethicist discuss the interplay between family-centered care and appropriate infection control. Reaching a balance between the 2 ideals is difficult and may require the facility and providers to engage in a deliberate conversation to determine how they will handle parental presence for such high-risk scenarios, including Ebola and other high-consequence pathogens, in their institution.