cssi/SciSciGPT-SciSciNet huggingface dataset:
Stability of AG337 : a thymidylate synthase inhibitor, in PVC infusion bags

AbstractThe stability of AG337, a selective thymidylate synthase inhibitor, in 5% Dextrose in Water (D5W) PVC infusion bags and sodium bicarbonate treated D5W infusion bags was studied at 30°C for seven days. AG337 Solution for Injection, 2% was diluted in D5W infusion bags to yield final AG337 concentrations of 4 mg/mL, 1 nig/mL and 0.1 mg/mL. For the sodium bicarbonate treated D5W infusion bags, the final concentrations of AG337 used were 4 mg/mL, 1 mg/niL and 0.2 mg/mL. The bags were prepared in triplicate and stored at 30°C. At predetermined time intervals, each bag was visually examined for presence of precipitates and samples were withdrawn for HPLC assay and pH testing. No precipitation was observed in any of the samples. The pH of the sodium bicarbonate treated D5W infusion bags remained constant throughout the study. The recovery of AG337 was greater than 93% in all samples tested. The recovery of methyl and propylparaben, used as preservatives in the formulation, however, decreased over time pro...
Characterization of human cytomegalovirus protease dimerization by analytical centrifugation.

Human cytomegalovirus, a member of the herpesvirus family, encodes a maturational protease required for processing of the assembly protein and virus replication. The protease is synthesized as a pr...
Aspirin Should Be Discontinued After Lobar Intracerebral Hemorrhage

Managing patients with spontaneous, nontraumatic intracerebral hemorrhage (ICH) can be frustrating. ICH represents 15% of all strokes, or 60 000 new cases each year in the United States and carries a grim prognosis, with 40% mortality and 50% severe disability among survivors.1 Making matters worse, for those patients lucky to survive their ICH, recurrent ICH is a substantial risk.2 The first important finding to consider in this patient is the lobar location of the bleeding. This information provides an important clue to the likely mechanism underlying the hemorrhage. In turn, identification of the involved mechanism allows stratification of the patient’s risk of recurrence, as well as tailoring of preventive strategies to decrease the risk of recurrence. Supratentorial ICH is classified as deep or lobar based on location. Deep hemorrhages affect deep supratentorial structures (basal ganglia …
Cloning and Expression of a Murine Fascin Homolog from Mouse Brain

The fascins are a widely distributed family of proteins that organize filamentous actin into bundles. We have cloned, sequenced, and expressed the murine homolog. Fascin is most abundant in brain and is found in other tissues including uterus and spleen. The deduced open reading frame encodes a protein of 493 amino acids with a molecular mass of 54,412 Da. Previous solubility problems with bacterially expressed fascins were overcome by producing the mouse protein as a fusion with Escherichia coli thioredoxin. A method for cleaving the fusion protein and for purifying active recombinant fascin is described. The N-terminal sequence and molecular mass estimated on SDS gels indicate that recombinant fascin is full-length. Two-dimensional gel electrophoresis suggests that recombinant fascin is post-translationally modified in a manner similar to that observed in mouse brain. Recombinant fascin and the fusion protein are recognized by monoclonal anti-fascin antibodies and will bundle rabbit skeletal muscle F-actin in vitro at a stoichiometry of 4.1:1 actin to fascin. Electron cryomicroscopy images show that the reconstituted bundles are highly ordered. However, their fine structure differs from that of echinoid fascin-actin bundles. This structural difference can be attributed to fascin.
The new labor market segmentation: Labor market dualism in the new economy☆

Abstract Dual labor market theory asserts that the American labor market is sharply divided between good jobs and bad jobs, and that mobility between these two segments of the market is severely restricted. The new labor market segmentation thesis argues that, as the practice of allocating workers to inferior jobs on the basis of race and sex has declined, employers have turned to nonstandard work arrangements and immigrants to supply labor for low-wage jobs. This paper presents a new method for measuring labor market dualism and identifying discrete labor market segments. This method allows us to examine the distribution of workers across these segments over the life course and to estimate the effects of nonstandard work and citizenship status on creating and placing workers into bad jobs. Three major findings are evident from this research. First, since the early 1970s the level dualism in the American labor market has increased substantially. Second, most workers who begin their careers in the secondary (bad) jobs eventually leave this labor market for better jobs, After young adulthood, most of the workforce is roughly divided between primary (good) intermediary (mediocre) jobs. Finally, results from the multivariate analysis support the new segmentation hypothesis. Combined, nonstandard work and citizenship now play a greater direct role in allocating workers to secondary and intermediary jobs than race or sex.
Automated lattice parameter measurement from HOLZ lines and their use for the measurement of oxygen content in YBa2Cu3O7-δ from nanometer-sized region

Abstract An algorithm is described which automatically adjusts values of lattice parameters or high voltage for best fit to the high-order Laue zone (HOLZ) lines in experimental convergent-beam electron diffraction (CBED) patterns for both cubic and non-cubic cell. The HOLZ line pattern is characterized by the distances between HOLZ line intersections. A standard definition of chi square is used to measure the goodness of fit. A general equation for HOLZ line positions based on the kinematic approximation is described. The effects of multiple scattering to the HOLZ line positions are discussed based on perturbation theory, the two-beam approximation, and on the Bethe potential. It is found that by avoiding the zone axis center the multiple scattering effects can be significantly minimized and accuracy in the lattice parameters increased. As an example, we have applied the method with dynamic corrections to lattice parameter measurement in YBa 2 Cu 3 O 7-δ from an area about 20 A diameter, using a field emission electron gun. We find a = 3.8252±0.0006 A in one of the two measurements. The ratio of the a and b axes gives the oxygen deficiency δ to be about 0.1.
Metiamide therapy of bleeding peptic ulcer during chronic hemodialysis.

An H2-receptor antagonist, metiamide, successfully controlled otherwise refractory recurrent bleeding from gastrojejunal ulcer in a patient with renal failure on chronic hemodialysis. Intravenous infusion at the rate of 2 mg/kg hr induced sustained achlorhydria, and the bleeding stopped promptly. Removal of the drug by renal excretion and dialysis was negligible. Pharmacologic H2 blockade allowed delay of gastric surgery in this fragile, decompensated patient.
A Nonlinear, Human-Centered Approach to Motion Cueing with a Neurocomputing Solver

This paper discusses the continuation of research into the development of new motion cueing algorithms first reported in 1999. In this earlier work, two viable approaches to motion cueing were identified: the coordinated adaptive washout algorithm or 'adaptive algorithm', and the 'optimal algorithm'. In this study, a novel approach to motion cueing is discussed that would combine features of both algorithms. The new algorithm is formulated as a linear optimal control problem, incorporating improved vestibular models and an integrated visual-vestibular motion perception model previously reported. A control law is generated from the motion platform states, resulting in a set of nonlinear cueing filters. The time-varying control law requires the matrix Riccati equation to be solved in real time. Therefore, in order to meet the real time requirement, a neurocomputing approach is used to solve this computationally challenging problem. Single degree-of-freedom responses for the nonlinear algorithm were generated and compared to the adaptive and optimal algorithms. Results for the heave mode show the nonlinear algorithm producing a motion cue with a time-varying washout, sustaining small cues for a longer duration and washing out larger cues more quickly. The addition of the optokinetic influence from the integrated perception model was shown to improve the response to a surge input, producing a specific force response with no steady-state washout. Improved cues are also observed for responses to a sway input. Yaw mode responses reveal that the nonlinear algorithm improves the motion cues by reducing the magnitude of negative cues. The effectiveness of the nonlinear algorithm as compared to the adaptive and linear optimal algorithms will be evaluated on a motion platform, the NASA Langley Research Center Visual Motion Simulator (VMS), and ultimately the Cockpit Motion Facility (CMF) with a series of pilot controlled maneuvers. A proposed experimental procedure is discussed. The results of this evaluation will be used to assess motion cueing performance.
Mindful: A Platform for Large-Scale Affective Field Research

In this work we present Mindful, a platform for defining, configuring, executing and distributing affective experiments to a large scale audience. This type of experiments measure the emotional reaction of participants to media content selected by experimenters. Furthermore, the platform manages profiles of registered users who have agreed to participate in an experiment as well as a data collection and analysis mechanisms. The analyzed data is then used to enrich users' profile and to better understand their emotional behavior. Throughout the paper we describe the platform in details and present a use case of how the platform is being used in practice.
Temporal Control of NF-κB Activation by ERK Differentially Regulates Interleukin-1β-induced Gene Expression

In cultured rat vascular smooth muscle cells, sustained activation of ERK is required for interleukin-1beta to persistently activate NF-kappaB. Without ERK activation, interleukin-1beta induces only acute and transient NF-kappaB activation. The present study examined whether the temporal control of NF-kappaB activation by ERK could differentially regulate the expression of NF-kappaB-dependent genes, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), vascular cell adhesion molecule-1 (VCAM-1), and manganese-containing superoxide dismutase (Mn-SOD). Treatment of vascular smooth muscle cells with interleukin-1beta induced the expression of iNOS, COX-2, VCAM-1, and Mn-SOD in a time-dependent manner, but with different patterns. Either PD98059 or U0126, selective inhibitors of MEK, or overexpression of a dominant negative MEK-1 inhibited interleukin-1beta- induced ERK activation and the expression of iNOS and COX-2 but had essentially no effect on the expression of VCAM-1 and Mn-SOD. The expression of these genes was inhibited when NF-kappaB activation was down-regulated by MG132, a proteasome inhibitor, or by overexpression of an I-kappaBalpha mutant that prevented both the transient and the persistent activation of NF-kappaB. Inhibition of ERK did not affect interleukin-1beta-induced I-kappaBalpha phosphorylation and degradation but attenuated I-kappaBbeta degradation. Thus, although NF-kappaB activation was essential for interleukin-1beta induction of each of the proteins studied, gene expression was differentially regulated by ERK and by the duration of NF-kappaB activation. These results reveal a novel functional role for ERK as an important temporal regulator of NF-kappaB activation and NF-kappaB-dependent gene expression.
Application of Comparative Transcriptional Genomics to Identify Molecular Targets for Pediatric IBD

Experimental models of colitis in mice have been used extensively for analyzing the molecular events that occur during inflammatory bowel disease (IBD) development. However, it is uncertain to what extent the experimental models reproduce features of human IBD. This is largely due to the lack of precise methods for direct and comprehensive comparison of mouse and human inflamed colon tissue at the molecular level. Here we use global gene expression patterns of two sets of pediatric IBD and two mouse models of colitis to obtain a direct comparison of the genome signatures of mouse and human IBD. By comparing the two sets of pediatric IBD microarray data, we found 83 genes were differentially expressed in a similar manner between pediatric Crohn’s disease (CD) and ulcerative colitis (UC). Up regulation of the chemokine (C-C motif) ligand 2 (CCL2) gene that maps to 17q12, a confirmed IBD susceptibility loci, indicates that our comparison study can reveal known genetic associations with IBD. In comparing pediatric IBD and experimental colitis microarray data, we found common signatures amongst them including: 1) up regulation of CXCL9 and S100A8; 2) cytokine-cytokine receptor pathway dysregulation; and 3) over-represented IRF1 and IRF2 transcription binding sites in the promoter region of up regulated genes, and HNF1A and Lhx3 binding sites were over-represented in the promoter region of the down regulated genes. In summary, this study provides a comprehensive view of transcriptome changes between different pediatric IBD populations in comparison with different colitis models. These findings reveal several new molecular targets for further study in the regulation of colitis.
Language Policy, Literacy, and Minority Languages

This paper surveys the development of language policy over the last 40 or more years, particularly with respect to linguistic minorities and the attendant problems of illiteracy and lack of access to basic education among these groups. While there are discernible, emerging trends in the area of language policy, we make considerable effort to point out that the evolution of such policy in the past has often been the product of an unpredictable confluence of national and international politics, economics (at all levels), social, cultural, and religious differences, intrigue, historical accident, human perversity, and serendipitous circumstances.
Protein-protein interactions with the acidic COOH terminus of the single-stranded DNA-binding protein of the bacteriophage T4.

Abstract The single-stranded DNA-binding protein of the bacteriophage T4 is encoded by gene 32. Monoclonal antibodies were raised against intact gene 32 protein (gp32). We mapped the epitopes recognized by 12 of these monoclonal antibodies; the epitopes are all within the COOH-terminal region of gp32. As shown by others, removal of the COOH terminus of gp32 abolishes the ability of the intact protein to bind to many T4 proteins involved in replication, recombination, repair, and late transcription. These results suggest that the COOH terminus of gp32 is a protein-binding domain. The COOH terminus is attached to a DNA-binding domain that includes a zinc finger. We propose a model in which the DNA-binding and protein-binding domains are used in T4 replication, recombination, repair, and late transcription. The COOH terminus of gp32 is very acidic and may form four negatively charged amphipathic alpha-helices, which could fold into a four-helix bundle when associated with other proteins. At least six of the monoclonal anti-gp32 antibodies bind to the COOH terminus of gp32 and to DNA. Similarities between the COOH terminus of gp32 and DNA are explored.
A calculator based program to optimize the simulation of breast irradiation

The simulation of breast fields using an isocentric set-up technique can be a lengthy process involving the placement of the isocentre, the determination of the gantry angles, and the selection of the lung shields, which in our center is one of six standard blocks. We show that with a body contour taken through central axis, five measurements and a calculator program, it is possible to significantly decrease the amount of time required to simulate a breast patient. We have developed a program for an HP48GX handheld calculator to determine the gantry angles, the isocentre, the field width, the standard angled block, and the couch and collimator rotation. The calculations are based on measurements of the field length, the horizontal distance between midline and mid axillary line, and the vertical distances from the mid axillary line to the inferior and superior beam border and central axis at midline. We use spherical geometry to perform the calculations to reflect the true environment and do not make any assumptions about the average patient's shape. For the simulation process a jig was developed that is inserted into the tray holder of the simulator to show the optical and radiological shadow of the calculated shielding along the patient's midline for clinical assessment during simulation and on the simulation film. The jig also has a holder for an aluminum wedge to improve the image quality of the simulation film. We admit that the lung shield increases the dose to the contralateral breast because of increased scatter and transmission through the shield; however, the block decreases the volume of irradiated lung while keeping the beam edge along the midline of the patient. The technique has been in use for two years and has resulted in time savings of up to 30% per patient. It has proven to be an easy and accurate way of setting up isocentric treatments to the breast.
Deterministic Model of Dermal Wound Invasion Incorporating Receptor-Mediated Signal Transduction and Spatial Gradient Sensing

During dermal wound healing, platelet-derived growth factor (PDGF) serves as both a chemoattractant and mitogen for fibroblasts, potently stimulating their invasion of the fibrin clot over a period of several days. A mathematical model of this process is presented, which accurately accounts for the sensitivity of PDGF gradient sensing through PDGF receptor/phosphoinositide 3-kinase-mediated signal transduction. Analysis of the model suggests that PDGF receptor-mediated endocytosis and degradation of PDGF allows a constant PDGF concentration profile to be maintained at the leading front of the fibroblast density profile as it propagates, at a constant rate, into the clot. Thus, the constant PDGF gradient can span the optimal concentration range for asymmetric phosphoinositide 3-kinase signaling and fibroblast chemotaxis, with near-maximal invasion rates elicited over a relatively broad range of PDGF secretion rates. A somewhat surprising finding was that extremely sharp PDGF gradients do not necessarily stimulate faster progression through the clot, because maintaining such a gradient through PDGF consumption is a potentially rate-limiting process.
Social Network Research in Organizational Contexts A Systematic Review of Methodological Issues and Choices

A large body of research has examined social networks in organizational contexts. While this work has enhanced scholars’ understanding of the antecedents and consequences of networks, missing from this literature is a comprehensive framework that simplifies and clarifies this complex body of work. In response, the authors develop a framework that classifies network research into four major categories, with the purpose of guiding scholars’ choices among the various theories, constructs, measures, research designs, and analytic strategies inherent in the social network literature. The authors also provide recommendations for future work aimed at advancing the state of network research in organizational contexts.
On the polarizability dyadics of electrically small, convex objects

This communication on the polarizability dyadics of electrically small objects of convex shapes has been prompted by a recent paper published by Sihvola and Lindell on the polarizability dyadic of an electrically gyrotropic sphere. A mini-review of recent work on polarizability dyadics is appended.
δ15N values in Lake Erie sediments as indicators of nitrogen biogeochemical dynamics during cultural eutrophication

Abstract We have measured the stable nitrogen isotope values ( δ 15 N) in two sediment cores sampled 15 years apart (1988 and 2003) from the Eastern Basin of Lake Erie and compared them to the total phosphorus (TP) and biogenic silica (BSi) concentrations in the 2003 core. Changes in the TP, BSi and total nitrogen (TN) accumulations in the 2003 core correspond to three stages in the trophic history of the lake that include the onset (∼ 1910 to ∼ 1950), peak (∼ 1950 to ∼ 1970), and amelioration (∼ 1970 to 2003) of eutrophication owing to accelerated nutrient loading. Decreasing BSi:TP atomic ratios (BSi:TP at ) from ∼ 1910 to ∼ 1970 suggest a gradual Si drawdown in the lake during its progressive eutrophication, which led to Si limitation and reduced diatom settling rates. δ 15 N values show pronounced variability in ∼ 1950 to ∼ 1970, which corresponds with rapid increases in N from runoffs from the lake catchment. A trend of gradually increasing δ 15 N values from ∼ 1910 to ∼ 1970 is likely the result of denitrification associated with the development of anoxic bottom waters in the Central Basin of the lake. This study illustrates the complexity of extracting environmental information from δ 15 N values in sediments and confirms the need for further studies of the multiple processes and their interactions that contribute to lacustrine δ 15 N records.
An Interface Phase Transition: Complete to Partial Wetting

When two fluid phases are near a critical point, one of them will be excluded from contact with any third phase that happens to be present by a wetting film of the other critical phase. A simple and quite general strategy that may be used to induce a phase transition from complete wetting of the third phase to incomplete wetting is to add a new component to the fluid phases chosen to drive the two phases away from their critical point. This strategy is illustrated for methanol-cyclohexane mixtures.
Factors influencing performance in the rapid separation of aflatoxins by micellar electrokinetic capillary chromatography.

Abstract Micellar electrokinetic capillary chromatography (MECC) is applied to the high-speed analysis of aflatoxins. Baseline separation of the four common aflatoxins G1, G2, B1 and B2, is accomplished in less than 30 sec. Small (25 μm) internal diameter capillaries are found to be critical in maintaining high efficiency under rapid MECC separation conditions. Van Deemter-like plots are generated in order to study the effects of capillary diameter and organic solvent on efficiency under high electric field conditions. Other experimental parameters affecting efficiency are investigated, including buffer concentration, surfactant concentration, and detector time constant. Simple on-column laser-based fluorescence detection, employing helium-cadmium laser radiation at 325 nm for excitation, allows for limits of detection in the range of 0.05-0.9 femtomoles injected for underivatized aflatoxins. Considerations important in the analysis of aflatoxins in real matrices are presented.
Elections with limited information: A multidimensional model

Abstract We develop a game-theoretic model of two-candidate competition over a multidimensional policy space, where the participants have incomplete information about the preferences and strategy choices of other participants. The players consist of the voters and the candidates. Voters are partitioned into two classes, depending on the information they observe. Informed voters observe candidate strategy choices while uninformed voters do not. All players (voters and candidates alike) observe contemporaneous poll data broken-down by various subgroups of the population. The results of the paper give conditions on the number and distribution of the informed and uninformed voters which are sufficient to guarantee that any equilibrium (or voter equilibrium) extracts all information.
Polarization and permeability (quantitative measurements)

Abstract The relationship between polarizability and permeability was studied on isolated frog skins during the initial stages of post mortem deterioration. The polarizability was determined by measuring the conductivity at a high ( C h ) and at a low frequency ( C l ) of A. C. and calculating the difference of these measurements expressed in percentage of C l (polarization index Δ). In one series of experiments the permeability for NaCl was determined, and in a second series that for urea. Both groups of experiments indicated that decrease of polarizability is associated with increase of permeability.
The Pd(II)-catalyzed homogeneous isomerization of hexenes

Abstract The isomerization of linear hexenes in alcoholic media, catalyzed by low concentrations of PdCl 2 in the presence of CuCl 2 , has been examined. Effects of reagent concentrations, alcohol and temperature are noted. Values of the rate and equilibrium constants for the ten rate-determining steps have been calculated for reactions in methanol at 30°C. The turnover number for the π-complex group is 48,100 ± 3,800 h −1 . No skeletal isomerization is detected. These isomerizations appear to proceed through π-allylic intermediates.
Upper Tract Urothelial Recurrence Following Radical Cystectomy for Transitional Cell Carcinoma of the Bladder: An Analysis of 1,069 Patients With 10-Year Followup

Purpose: Risk factors for upper tract recurrence following radical cystectomy for transitional cell carcinoma of the bladder are not yet well-defined. We reviewed our population of patients who underwent radical cystectomy to identify prognostic factors and clinical outcomes associated with upper tract recurrence.Materials and Methods: From our prospective database of 1,359 patients who underwent radical cystectomy we identified 1,069 patients treated for transitional cell carcinoma of the bladder between January 1985 and December 2001. Univariate analysis was completed to determine factors predictive of upper tract recurrence.Results: A total of 853 men and 216 women were followed for a median of 10.3 years (maximum 18.5). There were 27 (2.5%) upper tract recurrences diagnosed at a median of 3.3 years (range 0.4 to 9.3). Only urethral tumor involvement was predictive of upper tract recurrence. In men superficial transitional cell carcinoma of the prostatic urethra was associated with an increased risk of...
Comparative life cycle assessment of 2.0 MW wind turbines

Wind turbines produce energy with virtually no emissions, however, there are environmental impacts associated with their manufacture, installation, and end of life. The work presented examines life cycle environmental impacts of two 2.0 MW wind turbines. Manufacturing, transport, installation, maintenance, and end of life have been considered for both models and are compared using the ReCiPe 2008 impact assessment method. In addition, energy payback analysis was conducted based on the cumulative energy demand and the energy produced by the wind turbines over 20 years. Life cycle assessment revealed that environmental impacts are concentrated in the manufacturing stage, which accounts for 78% of impacts. The energy payback period for the two turbine models are found to be 5.2 and 6.4 months, respectively. Based on the assumptions made, the results of this study can be used to conduct an environmental analysis of a representative wind park to be located in the US Pacific Northwest.
Theoretical investigation of sub-ambient on-chip microprocessor cooling

Thermal management of microprocessors is a continuing challenge for electronics package design. Traditional thermal management strategies have focused merely on maintaining the junction temperature just below the maximum permissible limit. This work investigates the feasibility of sub-ambient microprocessor operation using an appropriate cooling technology. A simple model for the temperature dependence of various sources of power dissipation and performance parameters of a microprocessor shows significant power and performance improvement due to sub-ambient operation. It is further shown that the total system power consumption, including the power required for microprocessor cooling may decrease for operation in a specific temperature window. Below a threshold temperature, the total power consumption exceeds current values due to the rapid rise in cooling power. Operation at temperatures lower than the critical value may still be attractive for applications where performance improvement is critical. Stirling cycle-based pulse tube cooling technology offers a low cost, high power efficiency solution to facilitate low temperature microprocessor operation. First-order thermodynamic calculations presented in this work show that it may be possible to use pulse tube coolers to remove heat loads expected in typical microprocessor operation
Network political ecology: Method and theory in climate change vulnerability and adaptation research

This paper argues for the development of ‘network political ecology’, drawing on the insights from regional political ecology and recent advancements in network theories of scale, to meet the challenges of investigating the meso-scale problem of vulnerability and adaptation to climate change. ‘Network political ecology’, attentive to scale as socio-ecologically produced and grounded in a regional resource use system, is one such approach that fills this gap in middle-range theory necessary to understand the complex processes through which vulnerability manifests and adaptive capacity is produced. This method is exemplified through the case of groundwater-dependent irrigating farmers in Rajasthan, India.
Confidence in generic drug substitution.

Patients should have confidence that the generic drugs they are prescribed in the United States can be effectively substituted for the brand product or another generic product. Through new bioequivalence study designs for narrow therapeutic index (NTI) drugs and postapproval studies of generic substitution, the US Food and Drug Administration's (FDA's) ongoing generic drug regulatory science activities are designed to ensure successful generic substitution for all drug products. Clinical Pharmacology & Therapeutics (2013); 94 4, 438–440. doi:10.1038/clpt.2013.104
Wide Bandgap Semiconductors for Cold Cathodes: A Theoretical Analysis

In this paper we describe the field emission from wide band-gap semiconductor thin film electron sources as a three-step process. Internal field emission is the mechanism for electron injection at the metal-semiconductor cathode interface. Under an internal field, electrons injected into the conduction band can propagate quasi-ballistically through the thin semiconductor film. At the vacuum interface, they are field emitted across a PEA or NEA surface. Consistent with the electron injection mechanism we have done molecular dynamics simulations for GaN films with an initial energy distribution corresponding to a Fowler-Nordheim (FN) spectrum. Results demonstrate quasi-ballistic propagation and approximate preservation of the FN energy distribution. Furthermore, high levels of n-doping in GaN (≈ 1017cm−3) do not inhibit transport in thin films (<0.1 μm).
Indices of Obesity and Cardiometabolic Risk

See related article, pp 1029–1035 The prevalence of obesity in the United States has increased dramatically during the past 25 years.1 Many of the population-based cohort studies in the past decade have defined cardiovascular disease (CVD) risk associated with obesity in the context of diabetes mellitus and hypertension based on measurement of body mass index (BMI).2–4 It is not as clear which clinical measures of obesity to use in risk prediction for diabetes mellitus, hypertension, and CVD morbidity and mortality.2–5 In this issue, Bombelli et al6 explore the predictive value of BMI and waist circumference (WC) on risk prediction for new-onset impaired fasting glucose and diabetes mellitus, hypertension, and left ventricular hypertrophy (LVH). A prospective cohort of ≈3200 individuals from Italy were followed over 10 years with anthropometric measures of weight (BMI and WC), insulin sensitivity (fasting glucose and insulin), blood pressure (in- and out-of-office and ambulatory), and LVH by echocardiography. The population was risk stratified based on BMI and WC to determine new-onset insulin resistance, diabetes mellitus, hypertension, and LVH based on quintiles of relative risk. There was a graded relationship between increasing BMI, in the range of 21 to 29 kg/m2, and increasing risk for new-onset impaired fasting glucose, diabetes mellitus, and hypertension that became significant in the higher (eg, fourth and fifth) quartiles of BMI (>26 kg/m2). Unique …
Using gene co-expression network analysis to predict biomarkers for chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia. It is a highly heterogeneous disease, and can be divided roughly into indolent and progressive stages based on classic clinical markers. Immunoglobin heavy chain variable region (IgVH) mutational status was found to be associated with patient survival outcome, and biomarkers linked to the IgVH status has been a focus in the CLL prognosis research field. However, biomarkers highly correlated with IgVH mutational status which can accurately predict the survival outcome are yet to be discovered. In this paper, we investigate the use of gene co-expression network analysis to identify potential biomarkers for CLL. Specifically we focused on the co-expression network involving ZAP70, a well characterized biomarker for CLL. We selected 23 microarray datasets corresponding to multiple types of cancer from the Gene Expression Omnibus (GEO) and used the frequent network mining algorithm CODENSE to identify highly connected gene co-expression networks spanning the entire genome, then evaluated the genes in the co-expression network in which ZAP70 is involved. We then applied a set of feature selection methods to further select genes which are capable of predicting IgVH mutation status from the ZAP70 co-expression network. We have identified a set of genes that are potential CLL prognostic biomarkers IL2RB, CD8A, CD247, LAG3 and KLRK1, which can predict CLL patient IgVH mutational status with high accuracies. Their prognostic capabilities were cross-validated by applying these biomarker candidates to classify patients into different outcome groups using a CLL microarray datasets with clinical information.
Relevance of Kotter’s Model for Change in Successfully Implementing Lean

Though lean consists of numerous tools and techniques that are applicable to entire value stream, there are not many guidelines on how to implement lean from the managerial perspective. Lean implementation has succeeded and failed in many different organizations. This paper attempts to map success factors of lean implementation as suggested by some studies with Kotter’s eight steps model for change.
Dimensions of interorganizational interaction in social service agencies

The problem of interorganizational interaction was reviewed in terms of organizational structure and process, organizational size, and domain consensus between organizations. In order to determine the relationship between these factors and interorganizational interaction, interview data were gathered from personnel in a sample of 27 social service agencies. Cluster analysis results indicated a strong relationship between relationships of goal/task similarity and the degrees of interorganizational interaction reported by staff of these service agencies. There were negligible relationships between interorganizational relations, organization size, and internal organizational structures and processes, respectively. Conceptual and practical implications were discussed.
Sirt1 ablation promotes stress-induced loss of epigenetic and genomic hematopoietic stem and progenitor cell maintenance

The (histone) deacetylase Sirt1 is a mediator of genomic and epigenetic maintenance, both of which are critical aspects of stem cell homeostasis and tightly linked to their functional decline in aging and disease. We show that Sirt1 ablation in adult hematopoietic stem and progenitor cells (HSPCs) promotes aberrant HSPC expansion specifically under conditions of hematopoietic stress, which is associated with genomic instability as well as the accumulation of DNA damage and eventually results in a loss of long-term progenitors. We further demonstrate that progenitor cell expansion is mechanistically linked to the selective up-regulation of the HSPC maintenance factor and polycomb target gene Hoxa9. We show that Sirt1 binds to the Hoxa9 gene, counteracts acetylation of its histone target H4 lysine 16, and in turn promotes polycomb-specific repressive histone modification. Together, these findings demonstrate a dual role for Sirt1 in HSPC homeostasis, both via epigenetic regulation of a key developmental gene and by promoting genome stability in adult stem cells.
Growth hormone-stimulated insulin-like growth factor-1 expression in rainbow trout (Oncorhynchus mykiss) hepatocytes is mediated by ERK, PI3K-AKT, and JAK-STAT

Growth hormone (GH) initiates many of its growth-promoting actions by binding to GH receptors (GHR) and stimulating the synthesis and secretion of insulin-like growth factor-1 (IGF-1) from the liver and other sites. In this study, we used hepatocytes isolated from rainbow trout as a model system in which to determine the molecular signaling events of GH in fish. GH directly stimulated the phosphorylation of ERK, protein kinase B (Akt), a downstream target of phosphatidylinositol 3-kinase (PI3K), JAK2, and STAT5 in hepatocytes incubated in vitro. Activation of ERK, Akt, JAK2, and STAT5 was rapid, occurring within 5-10 min, and was concentration dependent. GH-induced ERK activation was completely blocked by the ERK pathway inhibitor, U0126, and the JAK2 inhibitor, 1,2,3,4,5,6-hexabromocyclohexane (Hex), and was partially blocked by the PI3K inhibitor LY294002. GH-stimulated Akt activation was completely blocked by LY294002 and Hex, but was not affected by U0126; whereas, STAT5 activation by GH was blocked only by Hex, and was not affected by either U0126 or LY294002. GH stimulated hepatic expression of IGF-1 mRNA as well as the secretion of IGF-1, effects that were partially or completely blocked by U0126, LY294002, and Hex. These results indicate that GHR linkage to the ERK, PI3K/Akt, or STAT pathways in trout liver cells requires activation of JAK2, and that GH-stimulated IGF-1 synthesis and secretion is mediated through the ERK, PI3K/Akt, and JAK-STAT pathways.
The Aging Consumer: What′s all the Fuss About Anyway?

Argues that marketers must consider more than ever the aging consumer. Considers the three demographic issues which must be taken into account before a strategy can be developed: first, stereotypes regarding the aging consumer must be disregarded; second, the aging consumer is not an isolated entity; and third, the aging consumer of the future will be very different from the aging consumer of today. Examines issues such as segmentation by age, marital status, buying power, changes in the work ethic, health, all of which have implications for the marketer.
Probucol increases the selective uptake of HDL cholesterol esters by Hep G2 human hepatoma cells.

A previous study in rats showed that even though probucol substantially lowers high density lipoprotein (HDL) levels, near-normal mass transport of HDL cholesterol esters (CE) to the liver is maintained by the induction of "selective" (direct) uptake of HDL CE. The present study describes a parallel result in cultured Hep G2 human hepatoma cells. Cells were preincubated in the presence or absence of probucol before measuring the uptake of doubly labeled HDL3 in the absence of probucol. Preincubation with probucol decreased the uptake of HDL3 particles (iodine-125-labeled N-methyltyramine cellobiose-apolipoprotein [125I-NMTC-apo] A-I uptake) but increased the uptake of [3H]cholesteryl oleyl ether in excess of 125I-NMTC-apo A-I (i.e., selective uptake) in a dose-dependent fashion. The reversibly cell-associated pool of CE tracer, a precursor for selective uptake, enlarged on probucol treatment, but the increase was not in proportion to the increase in selective uptake. HDL3 particle uptake decreased on probucol treatment. The decrease was evident after less than 20 minutes of probucol exposure and was maximal after 6 hours; in contrast, HDL3 CE selective uptake increased only after greater than 13 hours and had not reached a plateau after 20 hours. Thus, effects on particle uptake and selective uptake were dissociated in time.
Kinetic Buneman Instability in a Homogeneous Hot Electron Plasma

The development of Buneman kinetic instability in plasma with hot electrons and cold ions is investigated in the quasilinear approximation at current velocites close to the instability threshold values. It is shown that the contribution of electron's dielectric permeability in the dispersion equation is negligible and that quasilinear theory has in general stabilizing effect.
Cancer Biomarkers: Can We Turn Recent Failures into Success?

Disease biomarkers are used widely in medicine. But very few biomarkers are useful for cancer diagnosis and monitoring. Over the past 15 years, major investments have been made to discover and validate cancer biomarkers. Despite such investments, no new major cancer biomarkers have been approved for clinical use for at least 25 years. In the last decade, many reports have described new cancer biomarkers that promised to revolutionize the diagnosis of cancer and the management of cancer patients. However, many initially promising biomarkers have not been validated for clinical use. In this commentary, a plethora of parameters before sample analysis, during sample analysis, and after sample analysis that can complicate biomarker discovery and validation and lead to "false discovery" are discussed. Several examples of biomarker discoveries that were published in high-profile journals are also presented, as well as why they were not validated and the lessons learned from these false discoveries, so that similar mistakes can be avoided in the future.
Classifying with Gaussian Mixtures and Clusters

In this paper, we derive classifiers which are winner-take-all (WTA) approximations to a Bayes classifier with Gaussian mixtures for class conditional densities. The derived classifiers include clustering based algorithms like LVQ and k-Means. We propose a constrained rank Gaussian mixtures model and derive a WTA algorithm for it. Our experiments with two speech classification tasks indicate that the constrained rank model and the WTA approximations improve the performance over the unconstrained models.
A four-layer model for the heat budget of homogeneous land surfaces

The present model envisions the heat balance of a homogeneous land surface in terms of available energy, a set of driving potentials, and parameters for the physical state of the soil and vegetation. Two unique features of the model are: (1) the expression of the interaction of evaporation from the soil and from foliage by changes in the value of the saturation vapor pressure deficit of air in the canopy (the conclusions of this interaction being consistent with field observations); and (2) the treatment of sensible and latent heat exchange between the atmosphere and a soil consisting of two discrete layers.
Stimulus Typicality Determines How Broadly Fear Is Generalized

The ability to represent knowledge at the category level promotes the transfer of learning. How this ability integrates with basic forms of conditioned learning is unknown but could explain why conditioned fear is overgeneralized after aversive experiences. We examined the impact of stimulus typicality—an important determinant of category-based induction—on fear learning and generalization. Typicality is known to affect the strength of categorical arguments; a premise involving typical exemplars (e.g., sparrow) is believed to apply to other members, whereas a premise about atypical exemplars (e.g., penguin) generalizes more narrowly to similar items. We adopted this framework to human fear conditioning and found that fear conditioned to typical exemplars generalized more readily to atypical members than vice versa, despite equal feature overlap across conditions. These findings have implications for understanding why some fearful events lead to broad overgeneralization of fear whereas others are regarded ...
Mental imagery: in search of a theory.

It is generally accepted that there is something special about reasoning by using mental images. The question of how it is spe- cial, however, has never been satisfactorily spelled out, despite more than thirty years of research in the post-behaviorist tradition. This article considers some of the general motivation for the assumption that entertaining mental images involves inspecting a picture-like object. It sets out a distinction between phenomena attributable to the nature of mind to what is called the cognitive architecture, and ones that are attributable to tacit knowledge used to simulate what would happen in a visual situation. With this distinction in mind, the paper then considers in detail the widely held assumption that in some important sense images are spatially displayed or are depictive, and that examining images uses the same mechanisms that are deployed in visual perception. I argue that the assumption of the spatial or depictive nature of images is only explanatory if taken literally, as a claim about how images are physically instantiated in the brain, and that the literal view fails for a number of empirical reasons - for example, because of the cognitive penetrability of the phenomena cited in its favor. Similarly, while it is arguably the case that imagery and vision involve some of the same mechanisms, this tells us very little about the nature of mental imagery and does not support claims about the pictorial nature of mental images. Finally, I consider whether recent neuroscience evidence clarifies the debate over the nature of mental images. I claim that when such questions as whether images are depictive or spatial are formulated more clearly, the evidence does not provide support for the picture-theory over a symbol- structure theory of mental imagery. Even if all the empirical claims were true, they do not warrant the conclusion that many people have drawn from them: that mental images are depictive or are displayed in some (possibly cortical) space. Such a conclusion is incompatible with what is known about how images function in thought. We are then left with the provisional counterintuitive conclusion that the available evidence does not support rejection of what I call the "null hypothesis"; namely, that reasoning with mental images involves the same form of representation and the same processes as that of reasoning in general, except that the content or subject matter of thoughts experienced as images includes information about how things would look.
Tight Oracle Inequalities for Low-Rank Matrix Recovery From a Minimal Number of Noisy Random Measurements

This paper presents several novel theoretical results regarding the recovery of a low-rank matrix from just a few measurements consisting of linear combinations of the matrix entries. We show that properly constrained nuclear-norm minimization stably recovers a low-rank matrix from a constant number of noisy measurements per degree of freedom; this seems to be the first result of this nature. Further, with high probability, the recovery error from noisy data is within a constant of three targets: (1) the minimax risk, (2) an “oracle” error that would be available if the column space of the matrix were known, and (3) a more adaptive “oracle” error which would be available with the knowledge of the column space corresponding to the part of the matrix that stands above the noise. Lastly, the error bounds regarding low-rank matrices are extended to provide an error bound when the matrix has full rank with decaying singular values. The analysis in this paper is based on the restricted isometry property (RIP).