cssi/SciSciGPT-SciSciNet huggingface dataset:
Semi-analytical model for charge control in SiGe quantum well MOS structures

Abstract This paper discusses a semi-analytical model to calculate charge distribution in a silicon Metal-Oxide-Semiconductor (MOS) structure with a buried, strained Si 1−x Ge x quantum well. This charge distribution model is applicable to a device structure that consists of the following layer sequence: n -type substrate; p + doping spike; Si spacer layer; SiGe quantum well; Si cap layer; insulator and gate. The sheet density of mobile charge in the SiGe well is calculated using a quantum mechanical potential well description with the addition of a first-order perturbation analysis to accommodate the application of a gate bias. The carrier density in the inversion layer at the oxide/Si interface is found in a similar manner using the triangular well approximation. These expressions are coupled with an explicit algorithm to compute the electrostatic potential and depletion charge for various gate biases. Case studies are presented for quantum well MOS structures reported in the literature, and the carrier distributions found utilizing the semi-analytical model are in reasonable agreement with those calculated numerically via self-consistent solution of Schroedinger's and Poisson's equations. This semi-analytical framework allows a means to relate the effects of changing device physical parameters on circuit oriented characteristics. With an appropriate carrier transport description, this one-dimensional treatment can be expanded to quantum well MOS-Field Effect Transistors (MOSFETs) to quantify their static and dynamic characteristics.
Streptonigrin-transition metal complexes: binding to DNA and biological activity.

Summary Two effects of transition metal divalent cations on the behavior of the antitumor antibiotic streptonigrin are reported: (1) Metal ions such as Mn++, Zn++, and Cd++ promote an association of the antibiotic with double-stranded DNA. The metal ion causes a depression and slight red shift of the 365 nm absorption maximum of the antibiotic. Addition of DNA to the zinc-streptonigrin complex causes a further depression and red shift of the absorption maximum, indicating the formation of a DNA-streptonigrin-zinc complex. (2) These metal cations affect the biological activity of streptonigrin, in that they greatly enhance the lethal effect of the antibiotic on Escherichia coli . It is likely that the two effects are related.
Light Weight Composite Proppants: Computational and Experimental Study.

In this article, the computational and experimental techniques developed to understand and characterize the mechanical response of polymer coated walnut shell proppants is reported. Microscopy and single particle compression are employed to study cellular microstructure, elucidate influence of particle shape, and study cellular constitutive behavior. Computational models are created to simulate single-coated and uncoated particles under compression. The results reveal significance of the particle shape and constitutive material properties on its mechanical response. Polymer coating provides a marginal improvement in load transfer while stress and strain fields show a more gradual transition.
Saint-Venant's Principle and the Torsion of Thin Shells of Revolution

This paper is concerned with obtaining stress estimates for the problem of axisymmetric torsion of thin elastic shells of revolution subject to self-equilibrated end loads. The results are obtained in the form of explicit pointwise stress bounds exhibiting an exponential decay with distance from the ends, thus supplying a quantitative characterization of Saint-Venant’s principle for this problem. In contrast to arguments using energy inequalities, here we apply a technique, recently developed by the authors, based on the maximum principle for second-order uniformly elliptic equations.
The novel antiepileptic drug lacosamide blocks behavioral and brain metabolic manifestations of seizure activity in the 6 Hz psychomotor seizure model

Brain metabolic activation after 6 Hz electrical stimulation (32 mA, 3s stimulus duration) was assessed by autoradiographic analysis of 14C-2-deoxyglucose (2-DG) uptake. In addition, effects of the new antiepileptic drug lacosamide were examined on the stimulation-induced metabolic activation. The 6 Hz stimulation via corneal electrodes induced a robust increase 2-DG uptake in cerebral cortical regions, lateral amygdala, and the caudate-putamen. Many other brain regions were not affected by the stimulation, including the hippocampal formation, medial nuclei of the amygdala, thalamus, and hypothalamus. Lacosamide (20 mg/kg) injected i.p. 30 min before application of electrical stimulation antagonized completely the seizure-induced brain metabolic activation but did not affect basal 2-DG uptake. The data provide evidence that lacosamide antagonizes the neural activation induced by an electrical seizure stimulus, without suppressing normal brain metabolic activity.
Host population genetic structure and zooxanthellae diversity of two reef-building coral species along the Florida Reef Tract and wider Caribbean

In preparation for a large-scale coral restoration project, we surveyed host population genetic structure and symbiont diversity of two reef-building corals in four reef zones along the Florida reef tract (FRT). There was no evidence for coral population subdivision along the FRT in Acropora cervicornis or Montastraea faveolata based on microsatellite markers. However, in A. cervicornis, significant genetic differentiation was apparent when extending the analysis to broader scales (Caribbean). Clade diversity of the zooxanthellae differed along the FRT. A. cervicornis harbored mostly clade A with clade D zooxanthellae being prominent in colonies growing inshore and in the mid-channel zones that experience greater temperature fluctuations and receive significant nutrient and sediment input. M. faveolata harbored a more diverse array of symbionts, and variation in symbiont diversity among four habitat zones was more subtle but still significant. Implications of these results are discussed for ongoing restoration and conservation work.
The Structural Evolution of an Oceanic Plate

The dispersion of Rayleigh waves in the period range 15-170 s is used to detect the change in the structure of the lithosphere as it spreads away from the mid-ocean ridge. Using the single station method, group and phase velocities were measured for 42 paths within the Nazca plate. The focal mechanisms of the 11 source events were determined from P-wave first motion data and the azimuthal variation in Rayleigh wave amplitudes. The Nazca plate was divided into several regions whose boundaries are isochrons indicated by sea-floor spreading data. A characteristic pure-path dispersion curve was then computed for each age zone by least squares regression. A systematic variation in velocities with the age of the sea floor was observed. The greatest change in velocities for short periods (20-40 s) occurs in the first 10 My after the sea floor is generated at the ridge axis, presumably due to the rapid cooling of the upper part of the lithosphere. The phase and group velocities for periods greater than 40 s continue to increase for the next 50 My indicating a continued cooling and gradual thickening of the lithosphere. An apparent 2 per cent anisotropy in velocity was also found, with the maximum in the direction of spreading. Investigations into the source of this effect are in progress.
Comment on "Confidence Limits for Weibull Regression with Censored Data

A previous application of a W test of homogeneous shape parameters can be improved upon by applying the MLR test.
Reduction of Tissue Plasminogen Activator-Induced Hemorrhage and Brain Injury by Free Radical Spin Trapping after Embolic Focal Cerebral Ischemia in Rats

Thrombolytic stroke therapy with tissue plasminogen activator (tPA) remains complicated by serious risks of cerebral hemorrhage and brain injury. In this study, a novel model of tPA-induced hemorrh...
Meta-Analysis: Association Between Wrist Posture and Carpal Tunnel Syndrome Among Workers

Abstract Background Carpal tunnel syndrome (CTS) is a common work-related peripheral neuropathy. In addition to grip force and repetitive hand exertions, wrist posture (hyperextension and hyperflexion) may be a risk factor for CTS among workers. However, findings of studies evaluating the relationship between wrist posture and CTS are inconsistent. The purpose of this paper was to conduct a meta-analysis of existing studies to evaluate the evidence of the relationship between wrist posture at work and risk of CTS. Methods PubMed and Google Scholar were searched to identify relevant studies published between 1980 and 2012. The following search terms were used: “work related”, “carpal tunnel syndrome”, “wrist posture”, and “epidemiology”. The studies defined wrist posture as the deviation of the wrist in extension or flexion from a neutral wrist posture. Relative risk (RR) of individual studies for postural risk was pooled to evaluate the overall risk of wrist posture on CTS. Results Nine studies met the inclusion criteria. All were cross-sectional or case–control designs and relied on self-report or observer's estimates for wrist posture assessment. The pooled RR of work-related CTS increased with increasing hours of exposure to wrist deviation or extension/flexion [RR = 2.01; 95% confidence interval (CI): 1.646–2.43; p Conclusion We found evidence that prolonged exposure to non-neutral wrist postures is associated with a twofold increased risk for CTS compared with low hours of exposure to non-neutral wrist postures. Workplace interventions to prevent CTS should incorporate training and engineering interventions that reduce sustained non-neutral wrist postures.
Rapid thermal pyrolysis of interferometrically patterned resist

Abstract In recent years pyrolysis of interferometrically-patterned photoresists has produced three-dimensionally nanopatterned, electrically conductive carbon films with applications from energy storage to biological sensing. We investigate here conditions for rapid thermal pyrolysis that drastically reduce film processing time (from hours to minutes) while preserving the films’ unique nanoscale morphology, film adhesion, and electrochemical properties. We specifically show that heating rate dramatically affects nanoscale morphology, while reducing atmosphere composition, dwell time, and dwell temperature impact the electrochemical performance of these rapidly pyrolyzed nanostructures. Accelerated processing with rapid thermal pyrolysis may facilitate the expanded applicability and rapid fabrication of these promising nanostructured materials.
Effective Atmospheric Emissivity under Clear Skies

Abstract The effective atmospheric emissivity, F↓/(σT04), where F↓ is the downward radiative flux density and σT04 the blackbody flux density at the surface temperature T0, is computed for clear skies and straight temperature and dew-point soundings by means of emissivity integrations. Emissivity data by Jurica and by Staley and Jurica were used, and separate computations made for H2O, CO2, H2O-CO2 overlap, and O3. The effective atmospheric emissivity depends almost entirely on surface vapor pressure, decreases slightly with increasing surface elevation, and is essentially independent of surface temperature. The contribution by CO2 decreases from about 0,19 to about 0.17 as surface elevation increases from sea level to 710 mb. The contribution of overlap is negative and increases rapidly with increasing surface vapor pressure, becoming comparable to the CO2 contribution for very large vapor pressures. Measurements support the computations, but suggest, as has been found before, additional downward flux de...
Differential effects of age on brain gray matter in bipolar patients and healthy individuals.

This study examined possible differences in total gray and white matter brain content in bipolar patients and healthy individuals, and their relationship with age. 22 DSM-IV bipolar patients and 22 he
MIGRATION OF A7 IMMORTALIZED ASTROCYTIC CELLS GRAFTED INTO THE ADULT RAT STRIATUM

The A7 cell line is an SV4O large T antigen-immortalized astrocyte cell line produced from the neonatal rat optic nerve. Previous studies have demonstrated that A7 cells provide a favorable environment for the survival and growth of cultured neurons and can also stimulate axonal growth after grafting into the rat striatum. The current study was designed to investigate whether A7 cells grafted into adult rat striatum can migrate away from the implantation site. A7 cells were labelled in culture by incorporation of bromodeoxyuridine (BrdU) or by expression of an alkaline phosphatase transgene. The labelled cells were then transplanted into the left striatum of normal adult rats by introducing a blunt-end 22 gauge needle through a trephine hole. The rats were euthanized at periods of up to 30 days after grafting. The A7 cells did not appear to alter the cytoarchitecture of the surrounding brain parenchyma. Labelled A7 cells were observed in both gray and white matter areas, and many were located in areas free of damage due to the implantation procedure. The migration of the BrdU-labelled A7 cells with respect to the implantation needle track was determined on coronal sections. The radial migration distance from the needle tract was similarly determined on horizontal sections. A7 cells migrated progressively longer distances with increasing survival time of the animals: The largest migration distance (1,125 ± 52 μ) occurred at 30 days after grafting with an estimated migration rate of 31 μm per day. There was no significant directional polarity in the migration of these cells within the striatum. Some of the labelled A7 nuclear profiles were associated with blood vessels, some appeared to be associated with fiber bundles within the striatum, and some were found within the gray matter without apparent association with any anatomical structure. These results demonstrate that A7 immortalized astrocytic cells migrate away from a single implantation site following grafting into the adult rat striatum to populate a large area of the striatum. © 1995 Wiley-Liss Inc.
The seaward extension of submarine canyons off the northeast coast of the United States

Abstract Hudson, Wilmington, Washington, Veatch, Hydrographer, Gilbert, and Corsair are the principal canyon extensions that cross the continental rise off the East Coast of the United States. Genetically, the East Coast canyons can be grouped into river extension canyons that extend into the deep sea, and slump extension canyons that are short and discontinuous. Comparison of canyon extensions with sampling data suggests the presence of two cycles of canyon formation in the area. All canyon extensions exhibit high leveed right banks, and they bend to the left at the top of the rise. The two longest canyons, Wilmington and Hulson, may be partly erosional where they deepen and swing to the right, half way down the rise.
Theory of Cyclotron Resonance in Strained Silicon Crystals

The valence band structure in silicon single crystals subjected to an external uniaxial stress is investigated. The cyclotron resonance line for holes in such crystals is predicted to display a significant shift with increasing stress, if the split band populated with holes is associated with the quantum number ${M}_{J}=\ifmmode\pm\else\textpm\fi{}\frac{1}{2}$. This strain-induced shift is characterized by the following properties: (a) Its magnitude is of the order of 10% of the frequency for strains of the order of 2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}3}$; (b) it is anisotropic with respect to the relative orientation of the external magnetic field to that of the stress; (c) it must be absent if the band populated with holes is associated with the quantum number ${M}_{J}=\ifmmode\pm\else\textpm\fi{}\frac{3}{2}$. These properties in conjunction with the experimentally determined shifts, presented in the paper by Hensel and Feher, lead to a unique assignment of the band parameters which had been left ambiguous by previous experiments. A discussion of the line shape of hole resonance in a deformed crystal is also presented.
Studies on the regulation of insulin‐like growth factor binding protein 3 secretion in human osteosarcoma cells in vitro

Previous studies demonstrated that insulin-like growth factors (IGFs) are important autocrine and paracrine mitogens for human bone cells in vitro and that IGF binding proteins (IGFBPs) are important regulators of the biologic actions of IGFs. Thus, the actions of IGFs may be determined not only by their concentrations but also by the type and amount of IGFBPs produced by human bone cells at a local site in bone. In this study, we sought to determine the effects of dexamethasone, 1,25-(OH)2D3, and parathyroid hormone (PTH) on the secretion of IGFBP-3 in human osteosarcoma cell lines. Serum-free cultures of low- and high-alkaline phosphatase (ALP) SaOS-2, MG-63, and TE89 human osteosarcoma cells were treated for 24 or 48 h with the effectors and the conditioned media used for determination of IGFBP-3 using a radioimmunoassay. We report that (1) the basal rate of IGFBP-3 secretion (ng/mg cellular protein) was dependent upon cell type, with TE89 > low-ALP Saos-2 > MG-63 > high-ALP SaOS-2 cells, and did not correlate with either basal cell proliferation or basal cellular ALP activity; (2) dexamethasone (10(-12)-10(-7) M) inhibited IGFBP-3 secretion in a dose-dependent manner in low-ALP SaOS-2, MG-63, and TE89 cells but not in high-ALP SaOS-2 cells; (3) 1,25-(OH)2D3 (10(-11)-10(-8) M) stimulated IGFBP-3 secretion in a dose-dependent manner in MG-63, low-ALP SaOS-2, and high-ALP SaOS-2 cells, and the coaddition of TGF-beta and 1,25-(OH)2D3 increased synergistically IGFBP-3 secretion and cellular ALP activity in MG-63 cells; and (4) human PTH-(1-34) (0.1-100 ng/ml) had no significant effect on IGFBP-3 secretion in MG-63, low-ALP SaOS-2, or high-ALP SaOS-2 cells. We conclude that such agents as dexamethasone, 1,25-(OH)2D3, and PTH differentially regulate IGFBP-3 secretion in human osteosarcoma cells in vitro.
Understanding the role of health care providers during the transition of adolescents with disabilities and special health care needs.

Abstract Purpose To evaluate the role of health care providers in the transition from pediatric to adult health care for adolescents with disabilities and special health care needs (SHCN) from both the families' and providers' perspectives. Methods A total of 753 parents of adolescents with SHCN (e.g. developmental, physical, behavioral/emotional, learning, or health-related disabilities) were surveyed by questionnaire to assess their perceptions of their health care provider's level of involvement in various transition activities and the extent to which they felt it was the provider's responsibility to assist in a particular activity. One hundred forty-one health care providers (primarily pediatricians) completed a parallel survey to assess their level of participation in the same transition activities and the extent to which they felt it was their responsibility to assist with each transition activity. The questionnaire listed 13 different transition activities health providers may engage in to help young people prepare for adulthood and also asked questions about areas such as employment and health insurance. To investigate whether parents and providers share the same views regarding the involvement and responsibility of providers across the 13 transition activities, two sets of Student's t -tests were calculated. Results There were significant differences between providers and parents concerning both the level of provider involvement and the extent to which it was the provider's responsibility to assist in various transition activities (e.g., health providers reported significantly more involvement than did parents for 11 of the 13 transition activities and, compared with parents, providers reported that it was more within their role to assist in these 11 transition activities). Conclusion The findings suggest a need for health care providers and parents to have open discussions about the nature and extent to which providers assist families in key transition activities.
Nanometer size clusters and particles: a comparative study of magnetic behavior

Abstract The magnetic properties of large iron-oxo clusters stabilized within a shell of organic ligands and silica-coated or polymer-supported iron-oxide nanoparticles have been studied via Mossbauer spectroscopy. We make use of the clusters’ core/shell interface X-ray structural characteristics to shed light on atomic coordination distortions that may be imposed at the particle/matrix interface. Interface strains of 7% or larger are inferred which could induce atomic surface reconstruction and concomitant large surface and strain contributions to the magnetic anisotropy density, producing K ∼10 5 J/m 3 .
Adenoid cystic carcinoma of the cervix: A case report with implications for chemotherapeutic treatment

There have been 59 other cases of adenoid cystic carcinoma of the cervix reported in the literature. Therefore, little is known of the true biological behavior or therapeutic responsiveness of these tumors. We are reporting a case of adenoid cystic carcinoma of the cervix, FIGO Stage I-B, initially treated with radical hysterectomy and bilateral pelvic lymphadenectomy. Two years after surgery, the patient presented with recurrent disease in the pelvis and multiple lung metastasis. She subsequently was treated with chemotherapy consisting of cytoxan, Adriamycin, and cis-platinum with a sustained complete clinical response.
DNA Overstretching in the Presence of Glyoxal: Structural Evidence of Force-Induced DNA Melting

When a long DNA molecule is stretched beyond its B-form contour length, a transition occurs in which its length increases by a factor of 1.7, with very little force increase. A quantitative model was proposed to describe this transition as force-induced melting, where double-stranded DNA is converted into single-stranded DNA. The force-induced melting model accurately describes the thermodynamics of DNA overstretching as a function of solution conditions and in the presence of DNA binding ligands. An alternative explanation suggests a transformation into S-DNA, a double-stranded form which preserves the interstrand base pairing. To determine the extent to which DNA base pairs are exposed to solution during the transition, we held DNA overstretched to different lengths within the transition in the presence of glyoxal. If overstretching involved strand separation, then force-melted basepairs would be glyoxal-modified, thus essentially permanently single-stranded. Subsequent stretches confirm that a significant fraction of the DNA melted by force is permanently melted. This result demonstrates that DNA overstretching is accompanied by a disruption of the DNA helical structure, including a loss of hydrogen bonding.
Correlation between surface water contamination with amoeba and the onset of symptoms and diagnosis of amoeba-like keratitis

AIM—A seasonal variation was noted in the incidence of amoeba-like keratitis in Iowa. The level of contamination of amoeba in surface water has been found previously to vary on a monthly basis for Tulsa, Oklahoma, a region with a similar climate. It was hypothesised that this seasonal variation in amoeba-like keratitis correlated with the concentration of amoeba in surface water. METHODS—The monthly variation in the onset of symptoms was determined and date of diagnosis in 137 cases of amoeba-like keratitis, in Iowa, from January 1993 to the end of December 1996. RESULTS—Over a 4 year period a significant variation was found, on a monthly basis, in the onset of symptoms as reported by the patient. There were two peak periods per year when the onset of symptoms was most frequent: June and November. This corresponded closely with the concentration of amoeba in the ground water reported for a similar region in the mid-west (Tulsa, Oklahoma). A yearly increase was found in the number of cases diagnosed from January 1993 to the end of December 1996. CONCLUSIONS—This study supports the hypothesis that the concentration of amoeba in surface water may influence the rate of an amoeba-like keratitis infection. Keywords: amoeba; keratitis; water contamination; Acanthamoeba
Ion deposition induced modification of carbon nanopeapods: A computational study

Abstract Classical, many-body molecular dynamics simulations are used to study polyatomic ion beam deposition on carbon nanopeapods (C 60 -filled, single-walled carbon nanotubes). The results confirm the effectiveness of ion bombardment in inducing chemical modifications of nanopeapods. The simulations show how the coalescence of C 60 molecules starts with the damage of fullerenes and intermolecular bridging. In addition, the cross-linking of C 60 molecules to the tube wall is also predicted. This cross-linking results in changes in the electronic band structure as compared to the unmodified nanopeapod, which is investigated using first principles density functional theory.
Structural characterizations of coordination complexes of bis-triphenylphosphine copper(I) dicarboxylates

Abstract Dicarboxylate complexes of copper(I) with triphenylphosphine have been prepared in high yield from copper(I) butyrate and 0.5 equiv. of the corresponding dicarboxylic acid. The bis-triphenylphosphine copper(I) glutarate, adipate and terephthalate salts thus synthesized have been structurally characterized by single-crystal X-ray diffraction studies. The structures consist of two copper(I) centres each bound to two triphenylphosphine ligands with the metal centres bridged by the dicarboxylate group. In each of these derivatives the geometry about copper(I) is that of a distorted tetrahedron with a varying degree of asymmetry in the chelating carboxylate ligand. For example, in the (Ph3P)2 Cu(O2C(CH2)4CO2)Cu(Ph3P)2 complex the CuO bond distances at a single copper centre vary by 0.125 A. Even more dramatic CuO bond lenght differences were noted in the glutarate analogue. Nevertheless, in this instance the assymetry in CuO bond lengths were found to be influenced by the presence of solvent molecules in the crystal lattice, hence some of the asymmetry seen in the solid-state may be due to crystal packing forces.
Parallel simulated tempering dynamics of ligand–protein binding with ensembles of protein conformations

Abstract Simulated tempering dynamics with the simplified energy model and the ensemble of protein conformations have been performed for the SB203386 inhibitor binding with HIV-1 protease. Equilibrium simulations with multiple protein conformations implicitly incorporate protein flexibility and rank HIV-1 protease conformations according to the average ligand–protein interaction energies. Subsequent energy refinement with a molecular mechanics force field accurately quantifies the energetics of the low-energy ligand binding modes. The results suggest that the mobility of the SB203386 inhibitor is effectively restricted to two symmetry-related binding modes and this may prevent the inhibitor from adapting to distorted binding sites in mutant conformations.
From “Politico-Scientists” to Democratizing Science Movements: The Changing Climate of Citizens and Science

The Committee for Nuclear Information (CNI) was one of the first movements to translate expert knowledge to the public. It was led by “politico-scientists” who meant to advance an ethics of science by contributing to public understanding. Since then, citizens have taken research into their own hands, using it to frame issues, challenge corporate practices, and change policy. Movement methods that respond to consistent activist concerns about science are reflected in “democratizing science movements” (DSMs) that have grown, expanded, and changed in the past 50 years. This article compares the CNI to the Campaign for Safe Cosmetics, a group of organizations that have critiqued the hazardous ingredients in personal care products. The aim is to update our understanding of how movements use science to protect health and improve the environment since the CNI. Like CNI, Campaign activists have used science to educate the public about hazardous exposures; however, the Campaign reflects that over time, lay people ...
Perfusion deficit parallels exacerbation of cerebral ischemia/reperfusion injury in hyperglycemic rats

Magnetic resonance imaging (MRI) techniques were used to determine the effect of preexisting hyperglycemia on the extent of cerebral ischemia/reperfusion injury and the level of cerebral perfusion. Middle cerebral artery occlusion (MCAO) was induced by a suture insertion technique. Forty one rats were divided into hyperglycemic and normoglycemic groups with either 4 hours of continuous MCAO or 2 hours of MCAO followed by 2 hours of reperfusion. Diffusion-weighted imaging (DWI) was performed at 4 hours after MCAO to quantify the degree of injury in 6 brain regions. Relative cerebral blood flow (CBF) and cerebral blood volume (CBV) were estimated using gradient echo (GE) bolus tracking and steady-state spin echo (SE) imaging techniques, respectively. Brain injury correlated with the perfusion level measured in both SE CBV and dynamic GE CBF images. In the temporary MCAO model, mean lesion size in DWI was 118% larger and hemispheric CBV was reduced by 37% in hyperglycemic compared with normoglycemic rats. Hyperglycemia did not significantly exacerbate brain injury or CBV deficit in permanent MCAO models. We conclude that preexisting hyperglycemia increases acute postischemic MRI-measurable brain cellular injury in proportion to an associated increased microvascular ischemia.
Correlation betweenT c and elastic constants of (La?M)2CuO4

By an ultrasonic method, we measured the elastic constants of polycrystalline La1.85M0.15CuO4 withM=Ca, Ba, Sr. These materials show zero-resistance normal-superconductive transition temperatures of 19, 28, and 36K. VersusTc, all the elastic stiffnesses-bulk modulus, Young modulus, shear modulus-increase. Derived from the elastic constants and average atomic volume, the Debye temperature increases linearly withTc. In conventional BCS superconductors,Tc decreases with increasingΘD.
CFD study of effect of inclination angle on transport and reaction in hollow cylinder catalysts

Abstract This work examines how the angle to the flow of a 1-hole catalyst particle impacts its catalytic performance. Computational fluid dynamics (CFD) simulations are reported for flow past a single equilateral hollow cylinder under methane steam reforming conditions, for 1000 ≤ Re ≤ 10,000, and for approach angles from 0° to 90°. The simulations show that at 0°, the flat end of the particle causes separation and formation of a large wake region, while a jet-like flow results through the center hole. These flows result in a pattern of vortices behind the particle, with reverse flow along the particle length. These features are distorted as the approach angle increases, with boundary-layer formation on the upstream side of the particle and a complex vortex pattern on the downstream side. The flow through the particle hole decreases with incidence angle. Surface heat and mass fluxes decrease for the flat ends and the inside curved surface, and increase on the outside curved surface. Both reactant consumption and energy uptake show maxima as a result of the changes in transfer rates through the various particle surfaces, caused by the incident flow.
Cladistics and early hominid phylogeny.

Two recent reports (B. Asfaw et al. , 23 Apr., p. [629][1]; M. A. McCollum, 9 Apr., p. [301][2]) ([1][3], [2][4]) are skeptical about the utility of cladistic analysis to resolve questions about early hominid phylogeny. Although we disagree with aspects of these studies ([3][5], [4][6]), it is true
Design, Synthesis, and Evaluation of Novel, Highly CO2-Soluble Chelating Agents for Removal of Metals

The environmentally benign nature of CO2 and the ever-increasing regulations on the use of conventional solvents present CO2 as a solvent of choice for extraction processes for remediation of contaminated media, as a substitute for CFCs in precision cleaning processes, etc. However, because of the low solubility of metal ions and conventional metal chelating agents, there has been only limited progress in use of CO2 as a solvent in the extraction of metals. Consequently, we have embarked on the molecular design and synthesis of several novel, highly CO2-soluble chelating agents. This paper describes the synthesis and evaluation of these chelating agents that exhibit solubilities in excess of 100 mmol/L of CO2 at room temperature and pressures of 1100−2000 psi and extract as much as 98% of metals such as mercury, lead, arsenic, chromium, and iron from various matrices in laboratory-scale extractions that use pure CO2 as the solvent.
Making and testing refractories from high-density, high-purity magnesite powder

Test results for the trial batch of refractories made of dense magnesite powder in the converter lining in the trunnion zone showed that they are promising for application compared with ordinary dolomite goods with a pitch bond. The average wear of the test refractory is not more than 1.0 mm/heat, while dolomite-pitch shows a wear of 1.5 mm/heat. The resistance of blocks of dense magnesite powder in the lining of steel discharge apertures of a converter also proved to be higher than periclase (83 heats against 69).
A Surgical Model to Increase the Intestinal Absorptive Surface: Intestinal Lengthening and Growing Neomucosa in the Same Approach

Despite numerous investigations short bowel syndrome (SBS) is still an unsolved clinical problem. The purpose of this study was to develop a new surgical approach that combines both intestinal lengthening and growing neomucosa. The operative principle is based on a longitudinal division of an intestinal segment antimesenterically and a formation of two intestinal tubes out of bowel halves anastomosing one cutting edge to the incised mucosal midline and the other to the antimesenteric side of the constructed first intestinal tube, so that a common wall between the two hemiloops was created which leads to grow neomucosa. This procedure was applied to 11 rabbits. The hemiloops and neomucosa were investigated for its feasibility and morphologic characteristics. Gross and microscopic examinations at 8 weeks revealed that all the intestinal tubes were viable and patent. No anastomotic leakage was present. In all animals, the serosal surfaces of the common walls were covered with neomucosa that resembles the mucosa of the existing intestine morphologically; there was no significant difference in villus height, villus width at base, crypt depth, number of villi per unit serosal length, villus surface, and villus surface per unit serosa. The growth of neomucosa was completely a result of epithelialization without any evidence of contraction. The quantity and rate of neomucosal growth seems unaffected by intestinal segment length. Finally a two times increase in intestinal length, whereas the diameter halved and a statistically significant increase (P < 0.001) in total villus surface via growing neomucosa was obtained. This model might be useful in the management of SBS when supported by clinical and functional investigations.
Inhibitory effects of the guanine moiety on suzuki couplings of unprotected halonucleosides in aqueous media

In the Suzuki arylations of unprotected halonucleosides in aqueous media, 8-bromo-2‘-deoxyguanosine (8BrdG) couplings were slower to reach completion than the corresponding 8-bromo-2‘-deoxyadenosine (8BrdA) couplings. The guanine moiety has an acidic proton, which under our Suzuki conditions (pH ≅ 10) may be deprotonated to give an anion that can coordinate to palladium. The possibility that guanine coordination was responsible for the observed slower rates was explored using additive experiments in which nonhalogenated nucleosides were added to the Suzuki coupling reaction of 8BrdA or 4-bromotoluene and PhB(OH)2 and the reaction progress monitored by HPLC or GC. Adding dG slowed these reactions, and an induction period was observed. The addition of dA or 1-methyl-2‘-deoxyguanosine (1MedG) to these couplings did not affect the rate of conversion to product. Guanine coordination was further explored using 13C and 31P NMR spectroscopy, which implies that guanine is coordinating to palladium through N-1 or O...
Evaluation of Azathioprine on Lesion Severity and Lymphocyte Blastogenesis in Dogs With Perianal Fistulas

Fourteen dogs with perianal fistulas were entered into a prospective clinical study to investigate the effects of long-term azathioprine on clinical outcome and to determine if the clinical results correlated with lymphocyte blastogenesis tests. Complete remission of perianal fistulas was seen in eight (57%) of 14 dogs; partial remission occurred in one (7%) dog; and no response was detected in five (36%) dogs. The results of lymphocyte blastogenesis assays did not correlate with therapeutic response.
An analysis of the effect of lower extremity strength on impact severity during a backward fall.

At least 280 000 hip fractures occur annually in the U.S. at an estimated cost of $9 billion. While over 90 percent of these are caused by falls, only about 2 percent of all falls result in hip fracture. Evidence suggests that the most important determinants of hip fracture risk during a fall are the body's impact velocity and configuration. Accordingly, protective responses for reducing impact velocity and the likelihood for direct impact to the hip, strongly influence fracture risk. One method for reducing the body's impact velocity and kinetic energy during a fall is to absorb energy in the lower extremity muscles during descent, as occurs during sitting and squatting. In the present study, we employed a series of in verted pendulum models to determine: (a) the theoretical effect of this mechanism on impact severity during a backward fall, and (b) the effect on impact severity of age-related declines (or exercise-induced enhancements) in lower extremity strength. Compared to the case of a fall with zero energy absorption in the lower extremity joints, best-case falls (which involved 81 percent activation of ankle and hip muscles, but only 23 percent activation of knees muscles) involved 79 percent attenuation (from 352 J to 74 J) in the body's vertical kinetic energy at impact (KEv), and 48 percent attenuation (from 3.22 to 1.68 m/s) in the downward velocity of the pelvis at impact (v(v)). Among the mechanisms responsible for this were: (1) eccentric contraction of lower extremity muscles during descent, which resulted in up to 150 J of energy absorption; (2) impact with the trunk in an upright configuration, which reduced the change in potential energy associated with the fall by 100 J; and (3) knee extension during the final stage of descent, which "transferred" up to 90 J of impact energy into horizontal (as opposed to vertical) kinetic energy. Declines in joint strength reduced the effectiveness of mechanisms (1) and (3), and thereby increased impact severity However, even with reductions of 80 percent in available torques, KEv was attenuated by 50 percent. This indicates the importance of both technique and strength in reducing impact severity. These results provide motivation for attempts to reduce elderly individuals' risk for fall-related injury through the combination of instruction in safe falling techniques and exercises that enhance lower extremity strength.
On the Concentration Dependence of Far-IR Absorption by Sb-Doped Ge

Nisida and Horii have made detailed measurements of the concentration dependence of the far infrared absorption by Sb donors in Ge. A qualitative explanation of these observations is proposed, in which the strain produced by the donors themselves is able to account for the linewidths and asymmetry of the absorption lines in the low concentration range.
Critical illness hyperglycemia in pediatric cardiac surgery

Critical illness hyperglycemia (CIH) is common in pediatric and adult intensive care units (ICUs). Children undergoing surgical repair or palliation of congenital cardiac defects are particularly at risk for CIH and its occurrence has been associated with increased morbidity and mortality in this population. Strict glycemic control through the use of intensive insulin therapy (IIT) has been shown to improve outcomes in some adult and pediatric studies, yet these findings have sparked controversy. The practice of strict glycemic control has been slow in extending to pediatric ICUs because of the documented increase in the incidence of hypoglycemia in patients treated with IIT. Protocol driven approaches with more liberal glycemic targets have been successfully validated in general and cardiac critical care pediatric patients with low rates of hypoglycemia. It is unknown whether a therapeutic benefit is obtained by keeping patients in this more liberal glycemic control target. Definitive randomized controlled trials of IIT utilizing these targets in critically ill children are ongoing.
De Little Women de Louisa May Alcott aux Quatre filles du docteur March : Les traductions françaises d’un roman de formation au féminin

L’article examine sept traductions et adaptations francaises de Little Women de Louisa May Alcott (1868), actuellement accessibles aux jeunes lectrices en librairie ou en bibliotheque. Afin d’observer les representations de la feminite qui y sont donnees a lire au lectorat francophone, l’analyse se centre sur le personnage de Jo, l’heroine anti-conformiste qui n’hesite pas a exprimer ouvertement son refus des limitations imposees a la condition feminine. Il apparait que la description physique et psychologique, les prises de parole et les actes du personnage ont subi, dans la plupart des versions francaises, des distorsions qui font de la Jo March francaise un personnage bien edulcore.
Residual life predictions from vibration-based degradation signals: a neural network approach

Maintenance of mechanical and rotational equipment often includes bearing inspection and/or replacement. Thus, it is important to identify current as well as future conditions of bearings to avoid unexpected failure. Most published research in this area is focused on diagnosing bearing faults. In contrast, this paper develops neural-network-based models for predicting bearing failures. An experimental setup is developed to perform accelerated bearing tests where vibration information is collected from a number of bearings that are run until failure. This information is then used to train neural network models on predicting bearing operating times. Vibration data from a set of validation bearings are then applied to these network models. Resulting predictions are then used to estimate the bearing failure time. These predictions are then compared with the actual lives of the validation bearings and errors are computed to evaluate the effectiveness of each model. For the best model, we find that 64% of predictions are within 10% of actual bearing life, while 92% of predictions are within 20% of the actual life.
Regulation of Cyclin D1 Expression and DNA Synthesis by Phosphatidylinositol 3-Kinase in Airway Smooth Muscle Cells

We have shown in bovine tracheal myocytes that extracellular signal-regulated kinase (ERK) and Rac1 function as upstream activators of transcription from the cyclin D1 promoter. We now examine the role of phosphatidylinositol (PI) 3-kinase in this process. PI 3-kinase activity was increased by platelet-derived growth factor (PDGF) and attenuated by the PI 3-kinase inhibitors wortmannin and LY294002. These inhibitors also decreased cyclin D1 promoter activity, protein abundance, and DNA synthesis. Overexpression of the active catalytic subunit of PI 3-kinase (p110PI 3-KCAAX) was sufficient to activate the cyclin D1 promoter. Wortmannin and LY294002 failed to attenuate PDGF-induced ERK activation, and overexpression of p110PI 3-KCAAX was insufficient to activate ERK. p110PI 3-KCAAX-induced cyclin D1 promoter activity was not blocked by PD98059, an inhibitor of mitogen-activated protein kinase/ERK kinase. We next examined whether PI 3-kinase and the 21-kD guanidine triphosphatase Rac1 regulate cyclin D1 prom...
A randomized clinical trial to evaluate ready-made spectacles in an adult population in India

Background Ready-made spectacles (RMS) have advantages; however, visual performance and satisfaction has not been evaluated. Methods A 1-month, double-masked, randomized clinical trial comparing planned continued use and visual performance of RMS to Custom Spectacles (CS) in adults aged 18-45 years with ≥ 1 diopter (D) of uncorrected refractive error (URE). Results A total of 373 of 400 participants (93%) completed; mean age was 30 ± 9 years, and 58% were female. Average URE was 2.21 ± 1.3D and habitual vision was 0.58±0.21 logMAR (logarithm of Minimum Angle of Resolution, 20/63 +1 Snellen acuity). Ten participants with habitual vision better than 20/40 were excluded (3%). A lower proportion in the RMS group intended to continue to wear the study spectacles after 1 month (165/183, 90% vs 174/180, 97%, P=0.02). Spectacle vision in the eye with lower URE was 0.08±0.15 vs 0.02±0.08, P < 0.0001 and higher URE was 0.12±0.18 vs 0.02±0.08, P < 0.0001 (logMAR) for RMS and CS. Subgroup analyses excluding participants with astigmatism ≥2.00D and anisometropia ≥1.00D (74/363, 20%) found no difference in planned continued use (139/143, 97% vs 141/146, 97%, P=1.0) for RMS vs CS. Conclusions While vision is slightly better with CS, 90% of an adult population with URE planned to continue to use their RMS at 1 month. Furthermore, if those without high astigmatism or anisometropia are excluded, virtually all are satisfied with RMS and there is no difference when compared with CS. The findings of this study support the use of RMS for the delivery of refractive services in settings where there is a high level of need, limited resources and low access to refractive services.
Modeling Coax Cable EMI Shielding Performance for Automotive AM Broadcast Band Applications

Automotive broadcast reception systems typically use common coax cable to convey RF energy from the antenna to the broadcast receiver. In special cases a modified low capacitance coax is used for cross vehicle runs to enhance performance in the AM band. Coax is specified by characteristic impedance, optical coverage, DC resistance per unit length and RF loss versus frequency per unit length. Optical coverage and DC resistance serve to provide a gauge for relative shielding performance to EMI. EMI currents on the shield translate to an impressed voltage at receiver via the transfer impedance of the coax. This paper examines the shielding effectiveness of coax, transfer impedance and the relationship to signal source and return path impedance to noise coupling. A 2D quasi-static solver application (QuickField) is used for the analysis.
Recommendations for Benchmarking Web Site Usage among Academic Libraries

The Web sites that academic libraries are developing for their research communities represent an important new aspect of information management. Comparative statistical analysis of Web site usage among similar institutions would improve librarians’ ability to evaluate the effectiveness of their efforts. A centralized voluntary reporting structure for Web server usage statistics, coordinated by the Association of Research Libraries’ (ARL’s) Office of Statistics, would provide a significant service to academic librarians. Factors to consider in designing such a benchmarking program are discussed, based on a pilot study of Web site usage statistics from fourteen science and technology libraries.