cssi/SciSciGPT-SciSciNet huggingface dataset:
Provenance context entity (PaCE): scalable provenance tracking for scientific RDF data

The Resource Description Framework (RDF) format is being used by a large number of scientific applications to store and disseminate their datasets. The provenance information, describing the source or lineage of the datasets, is playing an increasingly significant role in ensuring data quality, computing trust value of the datasets, and ranking query results. Current provenance tracking approaches using the RDF reification vocabulary suffer from a number of known issues, including lack of formal semantics, use of blank nodes, and application-dependent interpretation of reified RDF triples. In this paper, we introduce a new approach called Provenance Context Entity (PaCE) that uses the notion of provenance context to create provenance-aware RDF triples. We also define the formal semantics of PaCE through a simple extension of the existing RDF(S) semantics that ensures compatibility of PaCE with existing Semantic Web tools and implementations. We have implemented the PaCE approach in the Biomedical Knowledge Repository (BKR) project at the US National Library of Medicine. The evaluations demonstrate a minimum of 49% reduction in total number of provenance-specific RDF triples generated using the PaCE approach as compared to RDF reification. In addition, performance for complex queries improves by three orders of magnitude and remains comparable to the RDF reification approach for simpler provenance queries.
Domains and the Magnetization Process

This chapter contains sections titled: Introduction Domain Wall Structure Domain Wall Observation Magnetostatic Energy and Domain Structure Single-Domain Particles Micromagnetics Domain Wall Motion Hindrances to Wall Motion (Inclusions) Residual Stress Hindrances to Wall Motion (Microstress) Hindrances to Wall Motion (General) Magnetization by Rotation Magnetization in Low Fields Magnetization in High Fields Shapes of Hysteresis Loops Effect of Plastic Deformation (Cold Work) Problems
Advances in structural studies of viruses by Raman spectroscopy

Assembly of an icosahedral capsid from a single species of coat protein subunit requires different subunit conformations at different lattice positions . In the double-stranded DNA bacteriophage P22 formation of correctly dimensioned capsids is mediated by interactions between subunits of coat and scaffolding proteins . We have employed Raman spectroscopy to investigate the specific intrasubunit conformations and intersubunit interactions required to close icosahedral shells which are competent to package the P22 genome . Preliminary results from coat protein subunits polymerized to form capsids in the presence and absence of the scaffolding protein indicate different distributions of subunit secondary structure for these two assembly conditions . The difference in structure affects a small portion of the coat subunit (z2 . 3 or 10 of 430 amino acid residues per subunit) and involves a transition from a-helix in the scaffoldassembled shell to B-strand in particles assembled without scaffold mediation . The secondary structure change is accompanied by changes in specific amino acid side chains indicative of a greater variety of side chain environments for particles assembled without scaffolding protein . The detection of small changes in protein structure is facilitated by recent developments in instrumentation and progress in the assignment of protein Raman bands to specific configurational states. Application of this methodology to the bacteriophage P22 tailspike protein has also permitted characterization of differences in thermal unfolding pathways of the wild-type protein and temperature-sensitive-folding mutant . Similar methods applied to mature icosahedral bacteriophages (P22 and TI) which package a double-stranded DNA chromosome reveal subtle but definitive perturbations to dsDNA conformation in the packaged state. 1.
Cyclic homologs of xanthines. I. Imidazo[4,5‐e][1,4]diazepine‐5,8‐diones

Synthese par benzylation/deribosylation de l'inosine suivie de scission basique du produit de reaction de la benzyl-7 hypoxanthine avec le bromoacetate d'ethyle puis de cyclisation du N-[amino-4 benzyl-1 imidazolecarbonyl-5] glycinate d'ethyle obtenu. Alkylation regiospecifique en 4 puis en 7 des composes obtenus
The Valuation and Market Rationality of Internet Stock Prices

This paper provides an analysis of some existing as well as new evidence of the relation between market prices and fundamentals in the Internet sector over the period January 1998 to February 2000. Appealing to results across a broad class of outcomes, we demonstrate a strong, circumstantial case against market rationality. In particular, we investigate (i) the level of Internet stock prices given their underlying fundamentals, (ii) responses of stock prices to information-based events, and (iii) the volatility of Internet prices. We review several potential explanations of these phenomena, including one based on heterogeneous beliefs across investors who are subject to short sales constraints. We provide a discussion of the empirical evidence supporting this latter explanation. Copyright 2002, Oxford University Press.
Interaction of lead and high ambient temperatures in the rat.

Abstract The effects of combined exposure to an environmental temperature of 23°C or 33°C, and 1% lead acetate in the diet on food intake, body weight, tissue lead content, and thermoregulation were examined in rats. Lead ingestion at an environmental temperature of 33°C resulted in reduced food intake and a decrease in body weight in a manner suggesting that the effects of the two agents were additive. Continuous exposure to 33°C produced a significant enhancement of the thermal response of rats subjected to a temperature of 44°C, which was not modified by lead exposure. The lead content of the adrenal glands, spleen, and bone marrow from lead-fed rats housed at 33°C was significantly increased over that of 23°C maintained animals. Liver, blood, skeletal muscle, and brain lead contents were similar to values obtained for rats receiving lead at 23°C.
Antiretroviral Therapy 2010 Update: Current Practices and Controversies

Over the past four years, significant advances have been made in human immunodeficiency virus (HIV) therapy. In addition to the release of two new classes of antiretrovirals, our understanding of the older antiretrovirals continues to improve. Multiple combination pills have been brought to market, simplifying the regimens for patient ease. New controversies have arisen, notably the role of antiretrovirals in the chronic inflammatory state that HIV infection produces, which may lead to excess cardiac, renal, and hepatic mortality. The optimum time to initiate antiretroviral therapy remains unknown but clinicians are treating HIV infection earlier in its course. In this article, we review these and other new issues relating to the care of the HIV patient.
Letter to the Editor-A Note on Pattern Separation

This note describes a linear programming method of separating two, not necessarily disjoint convex polyhedral sets in En. If the sets are disjoint, a strictly separating hyperplane is generated that maximizes and equalizes the distance between the sets and the hyperplane. If the sets intersect a hyperplane is generated that minimizes the maximum error.
Secretases as targets for the treatment of Alzheimer's disease.

Abstract Alzheimer's disease (AD) is the major cause of dementia in most developed countries. Treatment to modify this disease is currently unavailable, but needed urgently. The amyloid-cascade hypothesis proposes that amyloid β-peptide (Aβ), found in the plaques characteristic of AD, plays an early, critical role in the disease process. It follows that preventing the generation of Aβ could be therapeutically useful in all cases of AD. Inhibition of the secretases that produce Aβ from a large precursor protein is the main approach to achieve this goal.
Information load, time spent, and risk taking in complex decision making

The effect of the quantity of information which decision makers receive per unit time and the effect of the length of time spent in decision-making groups on the degree of risk taking in decision making were examined. A simulated decision-making task of some complexity was used for data collection to permit comparison with results obtained in simpler laboratory settings. It was found that risk taking increases with time spent in decision making and reaches highest levels under optimal information conditions. Parallels to studies in simpler environments were examined.
Experimental and numerical investigations of an orifice type cryogenic pulse tube refrigerator

Abstract A helium filled orifice type pulse tube refrigerator (OPTR) was designed, built and operated to provide cryogenic cooling. The OTPR is a traveling wave thermoacoustic refrigerator that operates on a modified reverse Stirling cycle. The experimental studies are carried out to characterize the performance of the OPTR at various values of the mean pressure of helium (0.35 MPa–2.2 MPa), amplitudes of pressure oscillations, frequencies of operation and sizes of orifice opening. A detailed time-dependent axisymmetric computational fluid dynamic (CFD) model of the OPTR is also developed to predict its performance. In the CFD model, the continuity, momentum and energy equations are solved for both the refrigerant gas (helium) and the porous media regions (the regenerator and the three heat-exchangers) in the OPTR. An improved representation of heat transfer in the porous media is achieved by employing a thermal non-equilibrium model to couple the gas and solid (porous media) energy equations. The computational results are compared with specific experimental results to validate the numerical model. The model predictions show better temporal comparisons with the experimental results when the effects of wall thicknesses and natural convective losses of the various components of the OPTR to the surroundings are included in the model.
Activated Drosophila Ras1 is selectively suppressed by isoprenyl transferase inhibitors.

Abstract Ras CAAX (C = cysteine, A = aliphatic amino acid, and X = any amino acid) peptidomimetic inhibitors of farnesyl protein transferase suppress Ras-dependent cell transformation by preventing farnesylation of the Ras oncoprotein. These compounds are potential anticancer agents for tumors associated with Ras mutations. The peptidomimetic FTI-254 was tested for Ras1-inhibiting activity in whole animals by injection of activated Ras1val12 Drosophila larvae. FTI-254 decreased the ability of Ras1val12 to form supernumerary R7 photoreceptor cells in the compound eye of transformed flies. In contrast, it had no effect on the related supernumerary R7 phenotypes of flies transformed with either the activated sevenless receptor tyrosine kinase, Raf kinase, or a chimeric Ras1val12 protein that is membrane associated through myristylation instead of isoprenylation. Therefore, FTI-254 acts as an isoprenylation inhibitor to selectively inhibit Ras1val12 signaling activity in a whole-animal model system.
Probabilistic Validation of Complex Engineering Simulations With Sparse Data

The challenges of validating expensive simulations with very sparse experimental data are addressed in this article. The effects of uncertainties in simulations and test data and their impact on validation are highlighted using several examples. Bayesian methods for calibration and tool validation are presented as the primary techniques for performing probabilistic validation. The applicability of the methods to complex engineering problems is discussed. The effect of prior assumptions on calibration and validation are explained through simple illustrative examples. Guidelines for planning simulations and experiments for validation are also provided.Copyright © 2014 by ASME
On Some Relations between the Solutions and the Parameters of Second‐Order Linear Differential Equations

The calculation of the Green's function for a point charge near an anisotropic planar diffuse layer leads to the differential equation U″ − k2D2(u)U = −2kδ(u − u′). Solutions for small and large k are obtained readily by a procedure equivalent to the principle of invariant imbedding. It is shown that the additional terms introduced in the solution for large k, due to the lack of smoothness in D(u) specifying the dielectric properties of the layer, may lead to singularities in the image potential. Similar considerations apply in the case of 1‐dimensional wave propagation through a stratified medium.
Brief screens for detecting alcohol use disorder among 18-20 year old young adults in emergency departments: Comparing AUDIT-C, CRAFFT, RAPS4-QF, FAST, RUFT-Cut, and DSM-IV 2-Item Scale.

Abstract Background This study compared six of the briefest screening instruments for detecting DSM-IV-defined Alcohol Use Disorder (AUD) among older adolescents treated in Emergency Departments (ED). Methods The AUDIT-C, the RAPS4-QF, the FAST, the CRAFFT, the RUFT-Cut, and 2-Items from the Diagnostic and Statistical Manual IV of the American Psychiatric Association [American Psychiatric Association (1994). Diagnostic and Statistical Manual of Psychiatric Disorders, (1994) (DSM-IV). 4th ed. Washington D.C.: American Psychiatric Association] criteria for AUD (heretofore referred to as the DSM-IV 2-Item Scale) were evaluated against the criterion of a current DSM-IV diagnosis of either alcohol abuse or dependence. The instruments were administered to 181 alcohol-using older adolescents (57% males; age range 18–20 years) in an ED and compared using Receiver Operator Characteristic (ROC) analyses against the criterion of a current DSM-IV diagnosis of alcohol abuse or dependence. Results Of these instruments, the DSM-IV 2-Item Scale performed best for identifying AUD (88% sensitivity and 90% specificity), followed by the FAST and the AUDIT-C. Conclusions Two items from the DSM-IV criteria for AUD performed best for identifying ED-treated older adolescents with alcohol use disorders. The FAST and AUDIT-C performed well, but are longer and more difficult to score in the hectic environment of the Emergency Department.
Improving snow processes in the Noah land model

[1] Snow is one of the most crucial land surface processes over middle and high latitudes. A widely known deficiency of the Noah land model as used in the National Centers for Environmental Prediction (NCEP) operational models and the Weather Research and Forecasting model (WRF) at the National Center for Atmospheric Research is that snowmelt occurs much too early. Through detailed diagnostics of the Noah output over the high-altitude Niwot Ridge forest site (40.03°N, 105.55°W) and a boreal forest site (53.9°N, 104.7°W), six deficiencies in Noah model physics are identified along with improved formulations that (1) consider the vegetation shading effect on snow sublimation and snowmelt; (2) consider under-canopy resistance; (3) revise the ground heat flux computation when snow is deep; (4) revise the momentum roughness length computation when snow is present; (5) revise the snow density computation near 0°C; and (6) increase the maximum iteration number from five to 30 in the turbulence computation. These revisions significantly improve Noah simulations of all snow processes such as snow water equivalent (SWE), snow depth, and sensible and latent heat fluxes over these two forest sites. The revisions were also evaluated (without tunings) with an independent forest site and a grassland site, further confirming the robust and positive impacts of these revisions on Noah snow simulations. These modifications maintain the Noah model structure and do not introduce new prognostic variables, allowing easy implementation into NCEP operational models and into WRF. Furthermore, they are found to be as good as, or slightly better than, a much more complicated land model in the snow simulation over the three forest sites.
Free and Hydrolytically Released Formaldehyde from DMDHEU-Finished Cotton Fabric:

The AATCC Sealed Jar test (Method 112) uses accelerated storage conditions to determine formaldehyde released from finished fabrics. A modification of the incu bation conditions of this test has been investigated in an attempt to provide a better measure of the free formaldehyde in fabric. By incubating test specimens at 20°C instead of at 49°C as in the standard test, there is less hydrolytic degradation of the finish. These modified conditions release 90% or more of the free formaldehyde from the test specimen but minimize the contribution of hydrolytically released formal dehyde from finish degradation due to incubation conditions of the test. Reproducibility of determinations was good. Typical results from DMDHEU-finished cottons in the modified and standard tests are presented. Sequential use of the tests in various com binations provides additional insight into free and easily released formaldehyde as well as that more difficult to release.
Evolution of primate DNA sequences

Abstract This study is concerned with comparing the DNA sequences of different mammals, mainly primates, by utilizing nucleic acid hybridization. Nucleotide sequence differences between different species have been quantitated. Rates of nucleotide sequence change have been calculated. These data suggest that nucleotide sequence change has been decreasing with the development of the primate line. They also indicate that the rate of nucleotide sequence change in Primates is 10 – 20 × lower than that for rodents during recent evolutionary times. When corrected for generation time the rodent and primate rates are essentially equal.
A study of neurogenesis in the forebrain of opossum pouch young.

Morphological changes of growing axons and dendrites are traced in rapid Golgi preparations of the olfactory bulb and the striatum and the parietal, cingulate, and hippocampal cortex. In age-graded series of opossum pouch young changes in the form and position of the differentiating neurons are related to the genesis of the neuronal architecture of each region. In the olfactory bulb there is a specific sequence of changes, starting with the formation of the olfactory glomeruli and the apical dendrites of the mitral cells and ending with the formation of the granule cell processes and the lateral dendrites of the mitral cells. In the ganglionic eminence, the external processes of neuroblasts form axons as they pass from the matrix zone into the presumptive striatal neuropil. Subsequently the perikarya move through the external processes from the matrix zone to the origins of the axons, the external processes disappear, and the dendrites of the striatal neurons start to form. The region of neuronal differentiation is defined by the intersection of the primitive processes of the neuroblasts with the growth cones of specific afferent axons. In the cerebral cortex the neuroblasts resemble primitive epithelial cells (spongioblasts). Their perikarya are in the matrix zone; their primitive processes extend between the internal and external limiting membranes. When afferent growth cones appear in the mantle zone of the parietal area, the perikarya of the pyramidal neuroblasts move to the external limiting layer through their primitive processes. Next these processes disappear; then axons and dendrites differentiate. The order of these events differs in other cortical areas. There is no sign of free, ameboid migration of the neuroblasts. The classical problems of neurogenesis are redefined in the light of these findings.
Crossing and anticrossing signals from Li7

The intensity of scattered radiation from the 22 P state in Li7 is calculated as a function of a static external magnetic field. The hyperfine levels of theJ=3/2,M j =−3/2 andJ=1/2,M j =−1/2 states cross or anticross near 4780 gauss. The intensity depends on the directions and polarizations of the incident and scattered beams. The peak of the derivative of the corresponding experimental values are 4783.8±0.2 gauss and 4779.8±0.9 gauss, respectively. The theoretical width of the anticrossing signal is 36 gauss which compares well with the experimental result of 35.72±0.36 gauss.
Optimal Deployment of Emissions Reduction Technologies for Construction Equipment

ABSTRACT The objective of this research was to develop a multiobjective optimization model to deploy emissions reduction technologies for nonroad construction equipment to reduce emissions in a cost-effective and optimal manner. Given a fleet of construction equipment emitting different pollutants in the nonattainment (NA) and near -nonattainment (NNA) counties of a state and a set of emissions reduction technologies available for installation on equipment to control pollution/emissions, the model assists in determining the mix of technologies to be deployed so that maximum emissions reduction and fuel savings are achieved within a given budget. Three technologies considered for emissions reduction were designated as X, Y, and Z to keep the model formulation general so that it can be applied for any other set of technologies. Two alternative methods of deploying these technologies on a fleet of equipment were investigated with the methods differing in the technology deployment preference in the NA and NNA...
The Legend of Good Women and the Affect of Invention

The Legend of Good Women conceptualizes invention as an affective force, linking the processes of emergence that precede the mind’s conscious recognition of emotion with the inventional processes which culminate in poetic art. The Prologue introduces a theoretical method for reconceptualizing invention, and the legends dramatize the process by which affect and invention collapse into emotion and poetry. In so doing, the poem attempts to gesture behind both the discourses that shape late medieval ideas of gender and the affect that infuses those discourses with their personal and cultural power.
Competitive inhibition of stereospecific opiate binding by local anesthetics in mouse brain.

Abstract Cationic local anesthetics inhibit competitively the stereospecific binding of naltrexone and etorphine on the mouse brain opiate receptor. In contrast, the inhibition produced by benzocaine, a non-cationic local anesthetic, is non-competitive. It is suggested that the cationic group of local anesthetics interacts with a specific anionic binding site on the opiate receptor and that there are certain structural similarities between the receptors for both types of drugs. It is evident from these studies that several drugs can unspecifically modify the pharmacologic effects of opiates and that they could be useful tools to further characterize the opiate receptor.
Mal de Mayo

Suggested citation for this article: Foster RT Sr. Mal de Mayo. Emerg Infect Dis [serial on the Internet]. 2007 Feb [date cited]. Available from http://www.cdc.gov/eid/content/13/2/337.htm
Epidemiology of viral hepatitis in Accra, Ghana

Abstract Endemic viral hepatitis is a major cause of urban morbidity and mortality among young adults in West Africa. In addition to the distinctive histopathological features and unusual clinical findings among patients admitted to hospital in Accra, Ghana, there are several important aspects to the epidemiology. The increased incidence of hepatitis in Accra during the past decade is due to a combination of the large immigration of non-immune young adults moving into the city plus the increased dispersal of the virus related to the dismal socio-economic circumstances in the shanty town areas. Host factors are of primary importance in determining the clinical course; fulminating disease was related to pregnancy, immigration, shanty town residency, physically active occupation, lack of education, and a low economic standing. In contrast, prolonged jaundice from hepatitis was related to inherent biological factors such as age, sex and G6PD deficiency.
Quantitative Assessment of Salmonid Escapement Techniques

Most reviews of salmonid escapement estimation techniques have been based on logistical considerations or site-specific applications and not on statistical first principles. We reviewed six categories of salmon escapement techniques: area-under-the-curve, carcass abundance, mark-recapture, passage count, peak count, and redd count methods, based on statistical accuracy (i.e., unbiasedness), precision, and the ability to meet model assumptions. Within each of these categories of escapement techniques, we make recommendations on the best approaches to use for valid estimates and suggest five considerations when selecting an escapement estimation method. Currently in the Pacific Northwest, peak spawner counts are the most commonly employed technique and least defensible on a statistical basis than other methods. We recommend statistical accuracy and precision be given higher consideration when monitoring often increasingly scarce salmon resources.
Isolation and characterization of a Trichoderma strain capable of fermenting cellulose to ethanol

The direct fermentation of cellulosic biomass to ethanol has long been a desired goal. To this end, we screened the environment for fungal strains capable of this conversion when grown on minimal medium. One strain, identified as a member of the genus Trichoderma and designated strain A10, was isolated from cow dung and initially produced about 0.4 g ethanol l–1. This strain cannot grow on any substrate under anaerobic conditions, but can ferment microcrystalline cellulose or several sugars to ethanol. Ethanol accumulation was eventually increased, by selection and the use of a vented fermentation flask, to 2 g l–1 when the fermentation was carried out in submerged culture in minimal medium. The highest levels of ethanol, >5.0 g l–1, were obtained by the fermentation of glucose. Little ethanol was produced by the fermentation of xylose, although other fermentation products such as succinate and acetate were observed. Strain A10 was also found to utilize (aerobically) a wide range of carbon sources. In addition, auxotrophic mutants were generated and used to demonstrate parasexuality by complementation between auxotrophs and between morphological mutants. The ability of this strain to use a wide variety of carbohydrates (including crystalline cellulose) combined with its minimal nutrient requirements and the availability of a genetic system suggests that the strain merits further investigation of its ability to convert biomass to ethanol.
HYDROXYL RADICALS DETECTED VIA BRAIN MICRODIALYSIS IN RATS BREATHING AIR AND DURING HYPERBARIC OXYGEN CONVULSIONS

AbstractMicrodialysis was done on 300–400 g, awake, male rats with microdialysis probes inserted through guide cannulas into the striatum (Bregma co-ordinates A 0.5, L 2.9, D –4.0 for guide cannulas implanted 5 days previously). Rats were exposed to hyperbaric oxygen (HBO; 6 atm absolute, 5 atm gauge pressure of oxygen with carbon dioxide absorbed by soda lime). Artificial cerebrospinal fluid (CSF) containing 5 mM sodium salicylate was perfused at 1 µl/min and collected over sequential 10 min intervals with rats breathing air, then HBO, and after decompression. Times to convulsions and duration and severity of convulsions were observed and recorded. CSF samples were analyzed for 2,3- and 2,5-dihydroxybenzoic acid (DHBA), reaction products of hydroxyl radicals with salicylate, by HPLC and compared to authentic standards. Recovery of DHBAs was 48% from fluid surrounding microdialysis probes, based on in vitro tests. The average time to the first convulsion was 21 min and rats convulsed an average of 4 times...
Swelling and time-dependent crack growth in SiC/SiC composites

Abstract SiC continuous-fiber composites are considered for nuclear applications but concern has centered on the differential materials response of the fiber, fiber/matrix interphase (fiber coating), and matrix. In our study, a continuous-fiber composite is simulated by four concentric cylinders to explore the magnitude of radial stresses when irradiation swelling of the various components is incorporated. The outputs of this model were input into a time-dependent crack-bridging model to predict crack growth rates in an environment where thermal and irradiation creep of SiC-based fibers is considered. Under assumed Coulomb friction the fiber–matrix sliding stress decreases with increasing dose and then increases once the pyrocarbon swelling reaches ‘turn around’. This causes an initial increase in crack growth rate and higher stresses in crack bridging fibers at higher doses. An assumed irradiation creep law for fine-grained SiC fibers is shown to dominate the radiation response.
N + + O − Neutralization Cross-Section Measurements Using a Superimposed-Beam Technique

The two-body ${\mathrm{N}}^{+}$ + ${\mathrm{O}}^{\ensuremath{-}}$ neutralization cross section has been measured via a superimposed-beam technique. The energy range in the barycentric coordinate system is 0.1-86 eV with about 0.1-eV resolution. The measured value of the neutralization cross section, $Q$, times the relative speed, $v$, is approximately constant (9\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}8}$ ${\mathrm{cm}}^{3}$/sec), except below 0.5 eV, where $\mathrm{Qv}$ increases rapidly with decreasing energy.
Outcomes Following Erosions of the Artificial Urinary Sphincter

Purpose: Artificial urinary sphincter urethral cuff erosion occurs in up to 5.0% of cases, presenting a complex management problem. We examine our experience with the eroded AUS, relating to preoperative risk factors, operative management and outcomes.Materials and Methods: We reviewed the medical records of 637 patients undergoing bulbar urethral AUS implantation from 1990 to 2003 for demographic and surgical variables.Results: Of the 637 records reviewed, 46 patients underwent 54 explantations of the AUS device for erosions, including 13 who had the primary implant performed at our institution and 33 being referred for management of erosion after implantation elsewhere. Our institution erosion rate was 2.2%. Mean followup after AUS reimplant following erosion was 27.8 months (range 1 to 180). Comorbidities were more prevalent in patients with erosions included hypertension (p = 0.006), coronary artery disease (p = 0.03), prior radiation therapy (p = 0.006) and prior AUS revisions (p = 0.0001). A majorit...
Modified therapeutic community aftercare for clients triply diagnosed with HIV/AIDS and co-occurring mental and substance use disorders.

This clinical trial evaluated a modified therapeutic community aftercare (MTC-A) program for a population triply diagnosed with HIV/AIDS, a substance use disorder, and a mental disorder. After six months of MTC residential treatment (MTC-R), subjects were randomly assigned to MTC-A (n=42) or to standard aftercare (C; n=34). Follow-up interviews at six and 12 months assessed eight outcome domains and adherence to prescribed HIV medication. A propensity model was used to re-balance the retrieved sample. At the six-month follow-up, High stratum MTC-A clients (those with greater psychological functioning and stable physical health at baseline) had greater improvement overall and for substance use and mental health than C clients in the same stratum. In contrast, C clients in the Low/Medium stratum (those with poorer psychological functioning and improved physical health) had more favorable outcomes overall and for substance use than their MTC-A counterparts; however, this stratum was not re-balanced effective...
The effect of age and exposure duration on cancer induction by a known carcinogen in rats, mice, and hamsters

Female Golden Syrian hamsters, F-344 rats, Swiss CD-1 mice, and B6C3F1 hybrid mice were exposed 6 hr/day, 5 days/week to carcinogenic levels of vinyl chloride (VC) for 6, 12, 18, or 24 months (rats and hamsters only). Other groups of rodents were held for 6 or 12 months and then exposed for 6 or 12 months. At the end of the study the incidence of VC-induced neoplasms was compared in each of the groups to assess the effects of duration of exposure and age at the start of exposure on carcinogenicity of VC. In rats, with early initial exposure, hemangiosarcomas, hepatocellular carcinomas, and mammary gland carcinomas occurred with increasing incidence with longer exposure duration. Rats held for 6 months before exposure developed VC-related neoplasms, while rats held 12 months before the start of exposure failed to show a significantly increased incidence of these neoplasms. In hamsters, hemangiosarcomas, mammary gland carcinomas, gastric adenocarcinomas, and skin carcinomas resulted from VC exposure. The highest incidence of malignant neoplasms occurred in hamsters exposed for the first 12 months, whereas exposure begun after 12 months of age did not cause neoplasms. In both strains of mice, VC exposure during the first 6 months of the experiment induced a high incidence of hemangiosarcomas and mammary gland carcinomas. Swiss mice also developed lung carcinomas after only 6 months of exposure. In all three rodent species an initial 12 month exposure to VC was adequate to detect its carcinogenic potential, but the shortened survival of VC exposed mice and hamsters precluded a meaningful comparison with longer periods of exposure. Exposures were most effective when started early in life.
Hair cell regeneration in the avian auditory epithelium

Regeneration of sensory hair cells in the mature avian inner ear was first described just over 20 years ago. Since then, it has been shown that many other non-mammalian species either continually produce new hair cells or regenerate them in response to trauma. However, mammals exhibit limited hair cell regeneration, particularly in the auditory epithelium. In birds and other non-mammals, regenerated hair cells arise from adjacent non-sensory (supporting) cells. Hair cell regeneration was initially described as a proliferative response whereby supporting cells re-enter the mitotic cycle, forming daughter cells that differentiate into either hair cells or supporting cells and thereby restore cytoarchitecture and function in the sensory epithelium. However, further analyses of the avian auditory epithelium (and amphibian vestibular epithelium) revealed a second regenerative mechanism, direct transdifferentiation, during which supporting cells change their gene expression and convert into hair cells without dividing. In the chicken auditory epithelium, these two distinct mechanisms show unique spatial and temporal patterns, suggesting they are differentially regulated. Current efforts are aimed at identifying signals that maintain supporting cells in a quiescent state or direct them to undergo direct transdifferentiation or cell division. Here, we review current knowledge about supporting cell properties and discuss candidate signaling molecules for regulating supporting cell behavior, in quiescence and after damage. While significant advances have been made in understanding regeneration in non-mammals over the last 20 years, we have yet to determine why the mammalian auditory epithelium lacks the ability to regenerate hair cells spontaneously and whether it is even capable of significant regeneration under additional circumstances. The continued study of mechanisms controlling regeneration in the avian auditory epithelium may lead to strategies for inducing significant and functional regeneration in mammals.
Glia determine the course of brain-derived neurotrophic factor-mediated dendritogenesis and provide a soluble inhibitory cue to dendritic growth in the brainstem

Cardiorespiratory control neurons in the brainstem nucleus tractus solitarius (NTS) undergo dramatic expansion of dendritic arbors during the early postnatal period, when functional remodeling takes place within the NTS circuitry. However, the underlying molecular mechanisms of morphological maturation of NTS neurons are largely unknown. Our previous studies point to the neurotrophin brain-derived neurotrophic factor (BDNF), which is abundantly expressed by NTS-projecting primary sensory neurons, as a candidate mediator of NTS dendritogenesis. In the current study, we used neonatal rat NTS neurons in vitro to examine the role of BDNF in the dendritic development of neurochemically identified subpopulations of NTS neurons. In the presence of abundant glia, BDNF promoted NTS dendritic outgrowth and complexity, with the magnitude of the BDNF effect dependent on neuronal phenotype. Surprisingly, BDNF switched from promoting to inhibiting NTS dendritogenesis upon glia depletion. Moreover, glia depletion alone led to a significant increase in NTS dendritic outgrowth. Consistent with this result, astrocyte-conditioned medium (ACM), which promoted hippocampal dendritogenesis, inhibited dendritic growth of NTS neurons. The latter effect was abolished by heat-inactivation of ACM, pointing to a diffusible astrocyte-derived negative regulator of NTS dendritic growth. Together, these data demonstrate a role for BDNF in the postnatal development of NTS neurons, and reveal novel effects of glia on this process. Moreover, previously documented dramatic increases in NTS glial proliferation in victims of sudden infant death syndrome (SIDS) underscore the importance of our findings and the need to better understand the role of glia and their interactions with BDNF during NTS circuit maturation. Furthermore, while it has previously been demonstrated that the specific effects of BDNF on dendritic growth are context-dependent, the role of glia in this process is unknown. Thus, our data carry important implications for mechanisms of dendritogenesis likely beyond the NTS.
The effect of ionic environment and mercury(II) binding on the alternative structures of DNA. An infrared spectroscopic study

Abstract Infrared spectroscopy was used to measure the effects of NaCl, NaNO 3 and HgCl 2 on the structure and structural transitions of DNA in hydrated films. The following conclusions are supported by the data. (1) The transition from the B- to the A-structural form in films of salt-free, calf-thymus DNA occurs between 86 and 75% r.h. Previous failures to obtain this transition in salt-free films and the finding that ca 4% (w/w) NaCl is needed to observe the B to A transition in films of DNA appear to be anomalies produced by the very slow kinetics for this transition. (2) The addition of NaCl to DNA increases the quantity of water absorbed at a given r.h. value and shifts the B to A transition to lower r.h. values. (3) Highly hydrated DNA (100% r.h.) with or without added NaCl exists in the B-helical structure for all samples examined. (4) DNA films containing one NaNO 3 per 6.7 nucleotide residues remained in the B-helical form to very low values of hydration. (5) The interaction of HgCl 2 with DNA to form the type I complex prevents the transition of DNA from the B- to the A-helical form but a conformational variation within the B family of structures was observed to occur between 94 and 75% r.h. (6) The primary sites of binding of Hg 2+ in the type-1 complex with the DNA are the AT base pairs. Hg 2+ binds to the N3 atom of thymine. Binding of Hg 2+ to AT pairs perturbs the CG pairs but has only a minor effect on the sugar—phosphate conformation.
Natural selection and the Michaelis constant.

Abstract Natural selection operating on a biological process with Michaelis-Menten kinetics adjusts the Michaelis (half-saturation) constant relative to ambient substrate concentration. From the perspective developed here, the relative fitnesses of alternative evolutionary “strategies” determine the trajectory of the Michaelis constant ( K m ) over evolutionary time. If substrate concentration is held relatively constant or fluctuates randomly about mean concentration over evolutionary time, while processing rate increases, K m tends toward a value greater than or equal to substrate concentration; if processing rate is held relatively constant over evolutionary time, K m tends to become large relative to substrate concentration. The diversity of the supportive evidence cited suggests a broad applicability of this argument across taxonomic groups and levels of biological organization.
Scientific and technical maturity of molten carbonate technology

Abstract The molten carbonate fuel cell (MCFC) is sometimes referred to as a “mature” technology. Thereby is implied that further development of the MCFC may not be expected to yield further innovation in technology and thereby diversity in applications. However, for a clear view of the role of the MCFC in tomorrow's energy systems it makes more sense to distinguish between “scientific maturity” and “technical maturity”. These concepts are discussed with special reference to the commercial prospects of the MCFC, as well as fuel cells in general. Of special interest are two cases where relative “maturity” or “immaturity” have a clear impact on potential applications, thereby either retarding or accelerating commercial development. The first case is that of the carbonate fuel cell fed by carbon, that is, a solid fuel, or by a semi-solid sludge, such as a biocarbon. The optimal design of such fuel cells is hindered by a “scientific immaturity”, specifically, the lack of insight in the intrinsic kinetics of these “substrates” in molten carbonate. An illustration is provided by the difficulty of interpreting open-circuit potential measurements of carbon in molten carbonate. The second case is the one-sided emphasis on scale-up of fuel cells, whereas scale-down (miniaturization) has much to offer. A consequence of this “technical immaturity” is that, initially, there was little interest in small hybrid energy systems employing small-scale fuel cells as well as other components such as batteries, PV cells, and (super)capacitors. This lag is now finally being overcome. Some conceptual and practical examples of fuel cell/battery hybrid systems with MCFC or SOFC are given.
Spectroscopic and Electrochemical Studies of Tungsten(VI) and Tungsten(V) Chloride and Oxychloride Complexes in a Sodium Chloride Saturated Sodium Chloroaluminate Melt

Raman and UV-visible absorption spectroscopies indicate that the addition of WCl[sub 6] or KWCl[sub 6] to a sodium chloride saturated sodium chloroaluminate melt at 175 C produces the tungsten (V) hexachloride anion [WCl[sub 6]][sup [minus]] can be oxidized to WCl[sub 6] via a reversible one-electron charge-transfer process with a voltammetric half-wave potential of 2.077 V referenced to aluminum in a pure sodium chloride saturated sodium chloroaluminate melt. With fast scan rate voltammetry, [WCl[sub 6]][sup [minus]] can be reduced to [WCl[sub 6]][sup 2[minus]] and [WCl[sub 6]][sup 3[minus]] via two consecutive one-electron reduction processes with half-wave potentials of 1.578 and 0.818 V, respectively. Both [WCl[sub 6]][sup 2[minus]] and [WCl[sub 6]][sup 3[minus]] form precipitates in this melt at this temperature. Using slow scan rate voltammetry, the reduction processes are complicated by coupled chemical reactions. Tungsten (VI) oxychloride, WOCl[sub 4], is stable in this melt, and can be reduced to tungsten (V) oxychloride via a reversible one-electron reduction process with a half-wave potential of 1.746 V. Absorption spectroscopy shows that the tungsten(V) chloride is [WOCl[sub 5]][sup 2[minus]]. Fast scan rate voltammetry indicates that tungsten (V) oxychloride exhibits a two-electron reduction process to produce a W(III) species. At slow scan rates, the reduction appears tomore » be complicated by coupled chemical reactions. Definitive characterization of the reduction mechanisms is prevented by film formation on the electrode surface during these reductions.« less
Reinventing the Formal Definition of Limit: The Case of Amy and Mike.

Abstract Relatively little is known about how students come to reason coherently about the formal definition of limit. While some have conjectured how students might think about limits formally, there is insufficient empirical evidence of students making sense of the conventional ɛ–δ definition. This paper provides a detailed account of a teaching experiment designed to produce such empirical data. In a ten-week teaching experiment, two students, neither of whom had previously seen the conventional ɛ–δ definition of limit, reinvented a formal definition of limit capturing the intended meaning of the conventional definition. This paper focuses on the evolution of the students’ definition, and serves not only as an existence proof that students can reinvent a coherent definition of limit, but also as an illustration of how students might reason as they reinvent such a definition.
Effects of priming goal pursuit on implicit sequence learning

Implicit learning, the type of learning that occurs without intent to learn or awareness of what has been learned, has been thought to be insensitive to the effects of priming, but recent studies suggest this is not the case. One study found that learning in the serial reaction time (SRT) task was improved by nonconscious goal pursuit, primed via a word search task (Eitam et al. in Psychol Sci 19:261-267, 2008). In two studies, we used the goal priming word search task from Eitam et al., but with a different version of the SRT, the alternating serial reaction time task (ASRT). Unlike the SRT, which often results in explicit knowledge and assesses sequence learning at one point in time, the ASRT has been shown to be implicit through sensitive measures of judgment, and it enables sequence learning to be measured continuously. In both studies, we found that implicit learning was superior in the groups that were primed for goal achievement compared to control groups, but the effect was transient. We discuss possible reasons for the observed time course of the positive effects of goal priming, as well as some future areas of investigation to better understand the mechanisms that underlie this effect, which could lead to methods to prolong the positive effects.
Experimental analysis of stresses in a buoy-cable system model using a birefringent fluid

An extension of the method of photoviscous analysis is presented which permits quantitative studies of strains associated with steady state vibrations of immersed structures. Strains can be determined both in the vibrating structure and in the surrounding fluid. The method is applied in an investigation of one form of behavior of buoy-cable systems loaded by the action of surface waves. Procedures are illustrated for evaluating directly from the strain data parameters useful to the buoy-cable system designer. The analysis performed is two-dimensional. The cable is modeled by a soft rubber strip, and the buoy by a round can floating on the surface of a birefringent fluid. A payload is simulated by a weight attached to the lower end of the strip. Waves of controllable frequency are produced by a device actuated by a shaker. Strains in the fluid and in the strip are determined from isochromatic and isoclinic data and the possible extension of the experimental results obtained to prototypes by means of scaling laws is suggested.
Activation of B Cells by a Dendritic Cell-Targeted Oral Vaccine

Production of long-lived, high affinity humoral immunity is an essential characteristic of successful vaccination and requires cognate interactions between T and B cells in germinal centers. Within germinal centers, specialized T follicular helper cells assist B cells and regulate the antibody response by mediating the differentiation of B cells into memory or plasma cells after exposure to T cell-dependent antigens. It is now appreciated that local immune responses are also essential for protection against infectious diseases that gain entry to the host by the mucosal route; therefore, targeting the mucosal compartments is the optimum strategy to induce protective immunity. However, because the gastrointestinal mucosae are exposed to large amounts of environmental and dietary antigens on a daily basis, immune regulatory mechanisms exist to favor tolerance and discourage autoimmunity at these sites. Thus, mucosal vaccination strategies must ensure that the immunogen is efficiently taken up by the antigen presenting cells, and that the vaccine is capable of activating humoral and cellular immunity, while avoiding the induction of tolerance. Despite significant progress in mucosal vaccination, this potent platform for immunotherapy and disease prevention must be further explored and refined. Here we discuss recent progress in the understanding of the role of different phenotypes of B cells in the development of an efficacious mucosal vaccine against infectious disease.