cssi/SciSciGPT-SciSciNet huggingface dataset:
Conditional value-at-risk: optimization algorithms and applications

This article has outlined a new approach for the simultaneous calculation of value-at-risk (VaR) and optimization of conditional VaR (CVaR) for a broad class of problems. We have shown that CVaR can be efficiently minimized using LP techniques. Our numerical experiments show that CVaR optimal portfolios are near optimal in VaR terms, i.e., VaR cannot be reduced further more than a few percent. Also, CVaR constraints can be handled efficiently using equivalent linear constraints, which dramatically improves the efficiency of the optimization techniques.
Genome, Proteome, and the Quest for a Full Structure–Function Description of an Organism

Using sequencing techniques developed in the 1990s, the genome projects have now successfully identified all the genes in several organisms encrypted in a four-letter alphabet. The gene products – proteins and RNAs coded by the genes – are the actual nuts and bolts of a living organism and the elucidation of their function and how they interact to sustain life remains one of the biggest challenges of the twenty-first century. Keywords: genome; proteome; DNA; RNA; protein; ORF; pathway; proteomics
The Relationship between Person-organization Fit and Employee Creativity: The Mediating Role of Creative Capital

This paper seeks to explore the relationship between person-organization fit and employee creativity. Based on the creativity literature, I develop a combined construct, namely creative capital which is defined as an individual’s resources from intrinsic motivation, task-relevant skills and knowledge, and external support, and propose that creative capital mediates the positive impact of person-organization fit on employee creativity. Theoretical and managerial implications including ideas on managing creativity (instead of managing for creativity) and future research directions are discussed.
Use of neural network techniques in a medical expert system

Expert systems in medicine have relied heavily upon knowledge-based techniques, in which decision making rules or strategies are derived through consultation with experts. These techniques, coupled with methods of approximate reasoning, have produced systems which model the human decision making process. This approach has the disadvantage of requiring extensive interviewing of experts for each new application. It is desirable to be able to supplement this information by extracting information directly from data bases, without expert intervention. In this article, a neural network model is used to extract this information, and then use it in conjunction with rule-based knowledge, incorporating techniques of approximate reasoning.
High‐Temperature Precipitation Hardening of Two‐Phase Y2O3‐Partially‐Stabilized ZrO2 Single Crystals: A First Report

High-temperature plastic deformation of Y/sub 2/O/sub 3/-stabilized ZrO/sub 2/ single crystals is of importance in the general field of oxide plasticity, and to complement the current interest in the strong and tough polycrystalline ceramics that can be produced in this system. Ingel and co-workers have studied the mechanical properties of single crystals in this system and observed unusually high high-temperature strengths in two-phase alloys. Lankford studied the plastic deformation of Y/sub 2/O/sub 3/-partially-stabilized and Y/sub 2/O/sub 3/-fully-stabilized ZrO/sub 2/ in compression between room temperature and 1150/sup 0/C and found that the strengths decreased rapidly with increasing temperature. No tetragonal ..-->.. monoclinic transformations occurred during the deformation of the partially stabilized single crystal. In the present paper, the authors report on the deformation of a crystal containing 4.5 mol% Y/sub 2/O/sub 3/ and being two-phase (high solute cubic (c) ZrO/sub 2/ and low solute tetragonal (t) ZrO/sub 2/ at the deformation temperature (1400/sup 0/C). Precipitation hardening was observed in two-phase (cubic plus tetragonal) Y/sub 2/O/sub 3/-partially-stabilized ZrO/sub 2/ single crystals deformed at 1400/sup 0/C. Slip was activated on (001)(110), primarily in Luders bands.
The Reincarnation of the Engineering “Shop”

The traditional hallmark of mechanical engineering education, the “shop”, is in the midst of a fundamental transformation. From its historic roots in the foundry and machine shop tucked away in the basement, it has evolved into a clean modern showcase of student activity, creativity and learning. The factors that led to its near-extinction in the 1980’s are discussed as well as the reasons for its current resurgence and modernization. An example of a modern reincarnation is presented — Penn State’s Learning Factory, which was awarded the 2006 Gordon Prize for Engineering Education by the National Academy of Engineering.Copyright © 2006 by ASME
Synthesis of [15N3]2-amino-7-methyl-1,8-naphthyridine†

†Revised version of a paper presented at the 12th Workshop of the International Isotope Society, Central European Division, June 17–18, 2004, Bad Soden, Germany.
Vision: When Does Looking Bigger Mean Seeing Better?

A recent study shows that our ability to discriminate the orientation of a visual pattern improves if the pattern appears larger.
Evolution of stratification over the New England shelf during the Coastal Mixing and Optics study, August 1996-June 1997

[1] To investigate the processes influencing the evolution of stratification over continental shelves a moored array was deployed on the New England shelf from August 1996 to June 1997. Temperature, salinity, and current observations spanning the water column were obtained at four midshelf sites, along with meteorological measurements at a central site to estimate the wind stress and the surface heat and freshwater fluxes. Four processes contributed to the seasonal evolution of the stratification. (1) The breakdown of the seasonal thermocline in fall was primarily due to wind forcing, not surface cooling, and occurred in four discrete steps associated with westward, along-coast wind stress events. Eastward wind stress events of similar magnitude did not reduce the stratification. (2) The water at midshelf remained stratified throughout most of the winter due to saltier shelf-slope front water displaced onshore by anomalously strong and persistent eastward alongcoast wind stresses. (3) The gradual redevelopment of the thermocline, beginning in April, was primarily a one-dimensional response to increasing surface heat flux. (4) Stratification in early April and throughout May was substantially enhanced by low-salinity water associated with river runoff from southern New England that was driven eastward and offshore by upwelling-favorable (eastward) wind stresses.
The Relationship of Fixed Carbon and Nitrogen Sources to the Greening Process in Euglena gracilis strain Z

SYNOPSIS The pattern of chloroplast development was followed in Euglena gracilis strain Z greening in media with a variety of fixed carbon and nitrogen sources. The greening pattern of cells grown in inorganic medium with added ethanol or glucose involves an inhibition of chloroplast development when compared to that of cells grown in inorganic medium alone. Several nitrogen sources were tested to ascertain their effectiveness in relieving the inhibition of chloroplast development by glucose. Of those, only 0.05% (w/v) (NH4)2 SO4 accelerated the recovery from the inhibition after most of the glucose had been removed from the medium by the cells. The other nitrogen sources tested were not effective. An inhibition of chloroplast development, similar to that observed in cells greening in the presence of glucose, was seen in cells greening in an ethanol-containing medium. These cells, however, had a different response upon the addition of 0.05% (NH4)2 SO4. They appeared to recover from the inhibition of chloroplast development, even before the ethanol was removed from the medium by the cells. A slight enhancement of chloroplast development was noted in cells greening in an inorganic medium with glycine or serine. Other amino acids tested had little or no effect.
The E2F Transcription Factors Regulate Tumor Development and Metastasis in a Mouse Model of Metastatic Breast Cancer

While the E2F transcription factors (E2Fs) have a clearly defined role in cell cycle control, recent work has uncovered new functions. Using genomic signature methods, we predicted a role for the activator E2F transcription factors in the mouse mammary tumor virus (MMTV)-polyomavirus middle T oncoprotein (PyMT) mouse model of metastatic breast cancer. To genetically test the hypothesis that the E2Fs function to regulate tumor development and metastasis, we interbred MMTV-PyMT mice with E2F1, E2F2, or E2F3 knockout mice. With the ablation of individual E2Fs, we noted alterations of tumor latency, histology, and vasculature. Interestingly, we noted striking reductions in metastatic capacity and in the number of circulating tumor cells in both the E2F1 and E2F2 knockout backgrounds. Investigating E2F target genes that mediate metastasis, we found that E2F loss led to decreased levels of vascular endothelial growth factor (Vegfa), Bmp4, Cyr61, Nupr1, Plod 2, P4ha1, Adamts1, Lgals3, and Angpt2. These gene expression changes indicate that the E2Fs control the expression of genes critical to angiogenesis, the remodeling of the extracellular matrix, tumor cell survival, and tumor cell interactions with vascular endothelial cells that facilitate metastasis to the lungs. Taken together, these results reveal that the E2F transcription factors play key roles in mediating tumor development and metastasis in addition to their well-characterized roles in cell cycle control.
Effectiveness of SO2 sorbents by thermogravimetry-combustion with coal

Abstract A new experimental method is described for non-isothermal thermogravimetry (TG) involving combustion of mixtures of sieved coal with sieved calcium-containing sorbents. This rapid TG method utilizes a baseline for TG combustion of coal alone, derives an equation that gives a semi-quantitative measure (±10% repeatability) of the coal's reactive sulphur retained by the sorbent, the extent of retention of S0 2 generated in situ during combustion varying with different sorbents. The method permits direct variation in separate experiments of the calcium-to-sulphur ratio during combustion and relative ranking of different sorbents by retention of reactive sulphur in combustion. Relative rankings are presented for three pre-calcined natural stones (two limestones and one dolomite); these results correlate with relative rankings from another TG method reported in the literature. It is suggested that this new method is useful for pre-screening the effectiveness of S0 2 sorbents considered for use in fluidizedbed combustion of coal.
Comparison of Non-Intrusive Polynomial Chaos and Stochastic Collocation Methods for Uncertainty Quantification

Non-intrusive polynomial chaos expansion (PCE) and stochastic collocation (SC) methods are attractive techniques for uncertainty quantification (UQ) due to their strong mathematical basis and ability to produce functional representations of stochastic variability. PCE estimates coefficients for known orthogonal polynomial basis functions based on a set of response function evaluations, using sampling, linear regression, tensor-product quadrature, or Smolyak sparse grid approaches. SC, on the other hand, forms interpolation functions for known coefficients, and requires the use of structured collocation point sets derived from tensor-products or sparse grids. When tailoring the basis functions or interpolation grids to match the forms of the input uncertainties, exponential convergence rates can be achieved with both techniques for general probabilistic analysis problems. In this paper, we explore relative performance of these methods using a number of simple algebraic test problems, and analyze observed differences. In these computational experiments, performance of PCE and SC is shown to be very similar, although when differences are evident, SC is the consistent winner over traditional PCE formulations. This stems from the practical difficulty of optimally synchronizing the formof the PCE with the integration approach being employed, resulting in slight over- or under-integration of prescribed expansion form. With additional nontraditional tailoring of PCE form, it is shown that this performance gap can be reduced, and in some cases, eliminated.
Micromechanical modeling of tungsten-based bulk metallic glass matrix composites

Abstract Micromechanics models are developed for tungsten (W)-based bulk metallic glass (BMG) matrix composites employing the Voronoi tessellation technique and the finite element (FE) method. The simulation results indicate that the computed elastic moduli are close to those measured in the experiments. The predicted stress–strain curves agree well with their experimentally obtained counterparts in the early stage of the plastic deformation. An increase in the W volume fraction leads to a decrease in the yield stress and an increase in the Young's modulus of the composite. In addition, contours of equivalent plastic strain for increasing applied strains provide an explanation why shear bands were observed in the glassy phase, along the W/BMG interface, and in the W phase of failed W/BMG composite specimens.
Intercalation and exfoliation relationships in melt-processed poly(styrene-co-acrylonitrile)/montmorillonite nanocomposites

Abstract The effects of surfactant structure on the morphology and mechanical properties of melt processed mixtures of poly(styrene-co-acrylonitrile) (SAN) with montmorillonite (MMT) organoclays were examined. The composite which exhibited the greatest change in gallery height, the highest modulus, and greatest aspect ratio (∼50) was produced from an organoclay with the lowest molecular weight surfactant, dimethyl hydrogenated tallow ammonium. For ammonium ion surfactants with ∼18 carbon hydrophobic tail(s), stack swelling, as measured by wide angle X-ray scattering (WAXS), was more strongly related to the reduced surfactant molecular weight than polarity or aromaticity of the head group substituents. A surfactant with a shorter tail length (∼12 vs. 18 carbon tail length) resulted in unswollen stacks in the composite. The swelling of the organoclay galleries seems to be explained by a balance of some favorable interactions of SAN with the montmorillonite platelet surface, versus repulsive mixing of aliphatic surfactant substituents with polar SAN. The repulsive nature of the latter increases as molecular weight of the head group substituents increases. A third factor is the platelet–platelet attraction that seems to explain the lack of swelling in the case of the shorter tail surfactant. Mechanical properties are also reported; and the composite moduli were found to compare to theoretical predictions using the Halpin–Tsai theory based on aspect ratios determined by transmission electron microscopy (TEM). The experimental aspect ratios do not seem to correlate with the WAXS gallery shifts. This and other evidence suggest that exfoliation in melt-processed SAN/MMT composites is not explained by intercalation behavior.
Behavioral features of CHARGE syndrome (Hall-Hittner syndrome) comparison with Down syndrome, Prader-Willi syndrome, and Williams syndrome.

CHARGE syndrome, or Hall–Hitner syndrome (HHS), has been delineated as a common syndrome that includes coloboma, choanal atresia, cranial nerve dysfunction (particularly asymmetric facial palsy and neurogenic swallowing problems), characteristic ear abnormalities, deafness with hypoplasia of the cochlea and semicircular canals, genital hypoplasia, and variable heart defects, orofacial clefting, tracheo-esophageal fistula, renal anomalies, thymic/parathyroid hypoplasia, spine anomalies, short broad neck with sloping shoulders, and characteristic facial features. We conducted behavioral and personality assessments in 14 boys with HHS syndrome aged 6–21 years, and compared their characteristics with similar data from 20 age-matched boys with Down syndrome (DS), 17 boys with Prader–Willi syndrome (PWS), and 16 boys with Williams syndrome (WS). We used the Reiss Profile of Fundamental Goals and Motivation Sensitivities, the Achenbach Child Behavior Checklist (CBCL), and the Aberrant Behavior Checklist (ABC). All 14 boys with HHS were legally deaf, and 10 of the 14 were also legally blind. In comparison these other syndromes, boys with HHS had behavior that resembled autistic spectrum disorder. They were socially withdrawn, lacked interest in social contact, and manifested reduced seeking of attention from others, with hyperactivity and a need to maintain order. Though the boys with HHS showed decreased social interaction, they were not as socially impaired as in classic autism. Their language was delayed due to dual sensory impairment, cranial nerve deficits, and chronic medical problems, but their language style was not abnormal (no echolalia or jargon, no scripted phrases, and no pronoun reversal). Boys with HSS appeared frustrated, but they were not aggressive, or at risk for delinquency, manifesting few stereotypic behaviors or unusual preoccupations. They did not have a restricted repertoire of activities and interests. Their behavioral features appeared to be due to dual sensory impairment affecting hearing and vision, rather than to primary autistic spectrum disorder, but successful remediation requires similar educational interventions, which are discussed herein. © 2005 Wiley-Liss, Inc.
Percutaneous penetration of hexachlorophene as related to receptor solutions.

The in vitro penetration of hexachlorophene (HCP) through the stratum corneum was investigated in relation to the receptor solution. Diffusion studies with human stratum corneum showed that 1.0% HCP in propylene glycol achieved a significantly greater (P < 0.025) mean maximum steady rate of penetration (over 1–24 hr) when normal saline was replaced by 0.2 m-phosphate buffer as the receptor solution. The varying degree of solubility of HCP in the reference solutions studied supports the penetration data. Under the experimental conditions used, HCP was not metabolized as it traversed the stratum corneum.
Electrical detection of spin transport in lateral ferromagnet–semiconductor devices

The development of semiconductor spintronics requires a reliable electronic means for writing, processing and reading information using spin-polarized carriers. Here, we demonstrate a fully electrical scheme for achieving spin injection, transport and detection in a single device. Our device consists of a lateral semiconducting channel with two ferromagnetic contacts, one of which serves as a source of spin-polarized electrons and the other as a detector. Spin detection in the device is achieved through a non-local, spin-sensitive, Schottky-tunnel-barrier contact whose electrochemical potential depends on the relative magnetizations of the source and detector. We verify the effectiveness of this approach by showing that a transverse magnetic field suppresses the non-local signal at the detection contact by inducing spin precession and dephasing in the channel (the Hanle effect). The sign of the signal varies with the injection current and is correlated with the spin polarization in the channel as determined by optical Kerr rotation measurements.
Using Proficiency as the Organizing Principle in an Advanced Speaking Course for Majors

While the proficiency movement has spawned numerous first and second year textbooks, very few proficiency-based materials are available for advanced students and majors. This article describes an advanced speaking course designed using the ACTFL Proficiency Guidelines as the organizing principle. Students prepared and performed a wide variety of communicative tasks at the Advanced and Superior levels, including narrating and describing, hypothesizing, supporting an opinion, debating and being interviewed for a job. Assignments involved students in pairs and small group work as well as in the class as a whole. Audio and video taping provided feedback. Oral Proficiency Interviews administered at the beginning and the end of the course indicated an improvement in OPI rating for some students.
Integrating Big Data: A Semantic Extract-Transform-Load Framework

Current tools that facilitate the extract-transform-load (ETL) process focus on ETL workflow, not on generating meaningful semantic relationships to integrate data from multiple, heterogeneous sources. A proposed semantic ETL framework applies semantics to various data fields and so allows richer data integration.
“It Just Tastes Better When It's In Season”: Understanding Why Locavores Eat Close to Home

This qualitative study explored food-related beliefs and attitudes of adults consuming a locally sourced diet. The primary author conducted three audiotaped, 120-minute-long focus groups using the theory of planned behavior as a theoretical framework. Questions were designed to elicit salient behavioral, normative, and control beliefs that modulate an individual's intention to eat a locally sourced diet. The belief that local food is more nutritious and healthful than conventionally grown food is a major motivator for eating a local diet. In addition, the influence of family and significant others is important. Finally, cost and accessibility are perceived barriers to eating locally. Subthemes include inherent trust of local farmers and a moral conscience to eat locally. Future research may include a quantitative evaluation of the findings from these focus groups and analysis of local eating behaviors to determine the nutritional quality of this diet.
Buckling of Open Cylindrical Shells with Torsionally Stiff Rectangular Edge Stiffeners

The bifurcation strength of open cylindrical shells with torsionally very stiff edge stiffeners of rectangular cross section subject to uniform axial load is determined analytically using Donnell's simplified equations. A deflection function with arbitrary undetermined coefficients satisfying the end conditions is assumed. The stress resultants are derived in terms of these coefficients. These stress resultants and the deflections of the shell are made to satisfy the assumed boundary conditions along the longitudinal edges. The resulting determinant of the equations is set equal to zero in order to obtain the critical buckling stress. The limited results obtained in this paper indicates an interesting phenomena that the critical buckling stress of a shell with a shallow edge stiffener is well above the critical buckling stress of a shell with free edges, whereas the buckling of a shell with moderate depth edge stiffeners in a narrow region is only slightly above the critical buckling stress of a shell with free edges.
Brain-Derived Neurotrophic Factor and TrkB Modulate Visual Experience-Dependent Refinement of Neuronal Pathways in Retina

Sensory experience refines neuronal structure and functionality. The visual system has proved to be a productive model system to study this plasticity. In the neonatal retina, the dendritic arbors of a large proportion of ganglion cells are diffuse in the inner plexiform layer. With maturation, many of these arbors become monolaminated. Visual deprivation suppresses this remodeling. Little is known of the molecular mechanisms controlling maturational and experience-dependent refinement. Here, we tested the hypothesis that brain-derived neurotrophic factor (BDNF), which is known to regulate dendritic branching and synaptic function in the brain, modulates the developmental and visual experience-dependent refinement of retinal ganglion cells. We used a transgenic mouse line, in which a small number of ganglion cells were labeled with yellow fluorescence protein, to delineate their dendritic structure in vivo. We found that transgenic overexpression of BDNF accelerated the laminar refinement of ganglion cell dendrites, whereas decreased TrkB expression or retina-specific deletion of TrkB, the cognate receptor for BDNF, retarded it. BDNF-TrkB signaling regulated the maturational formation of new branches in ON but not the bilaminated ON-OFF ganglion cells. Furthermore, BDNF overexpression overrides the requirement for visual inputs to stimulate laminar refinement and dendritic branching of ganglion cells. These experiments reveal a previously unrecognized action of BDNF and TrkB in controlling cell-specific, experience-dependent remodeling of neuronal structures in the visual system.
The demographics of gubernatorial appointees: Toward an explanation of variation

This study examines the various factors that could potentially predict or explain demographic diversity in high-level gubernatorial appointments in state government. In particular, it identifies and analyzes a set of variables that could help answer the question: Under what conditions are governors more likely to appoint higher proportions of women and people of color to topranking executive branch positions? This question, not yet addressed by researchers, is particularly salient in the current climate of accelerated devolution. Decisionmakers in state governments play a greater role in determining policy across an increasingly wide range of areas than at any time in recent history. From the standpoint of representativeness, the demographic background of state policymakers increases the stakes of those who participate, particularly in terms of policy outcomes. Thus, it is especially important to identify the participants in state-level policy arenas and the factors that could predict their appointments. The representation of women and people of color in the executive branch of government has long been of interest to social scientists (Burrell, 1997; Carroll, 1987; Cayer & Sigelman, 1980; Guy, 1992; Kellough, 1990; Kelly, 1991; Kelly & Guy, 1991; Meier, 1975, 1993; Rosenbloom & Featherstonhaugh, 1977; Saltzstein, 1983, 1986; Selden, 1997; Sigelman, 1976). Numerous studies report on the representation of women, African-Americans, Latinos, and other ethnic groups in executive branches at all levels of government. Researchers consistently view the representation of these groups in government as a critical means of strengthening democracy, helping to legitimize government among disenfranchised groups, promoting equity, enabling government to serve as a model employer for private and nonprofit firms, and advancing and testing theories of representative bureaucracy. Several of these studies further examine factors that could potentially explain the representation of v all wield influence rooted in their political ties to the chief executive. Dometrius (1984, p. 127) emphasizes the importance of women and people of color in high-level, appointed positions and argues that they
A comparison of readout techniques for high-resolution imaging with microchannel plate detectors

Several imaging techniques are available which enable microchannel plate (MCP) detectors to achieve spatial resolutions limited by the MCP pore spacing. Without exception, these techniques utilize some form of interpolation scheme, which may rely on charge or light division, or electronic signal timing. We present a review of the devices currently available and discuss the merits and drawbacks of these competing schemes.
Climate for Scandal: Corporate Environments that Contribute to Accounting Fraud

We examine the governance characteristics, earnings quality, growth rates, dividend policy, and compensation structure of 97 firms recently under investigation by the Securities and Exchange Commission (SEC) for accounting fraud. Our results show that the corporate environment most likely to lead to an accounting scandal manifests significant growth and accounting practices that are already pushing the envelope of earnings smoothing. Firms operating in this environment seem more likely to tip over the edge into fraud if there are fewer outsiders on the audit committee and outside directors appear overcommitted.
Thermal transport in heavily deformed and γ -irradiated LiF at temperatures near 1 k

Abstract The thermal conductivity κ of heavily deformed LiF crystals has been measured at temperatures T ⩾ 0.5 K following exposure of the samples to γ irradiation. The results are in agreement with recent measurements of ballistic phonon propagation in similar samples at an equivalent temperature of ≈ 4 K. A fraction of the phonons have a mean free path of order 1 cm in the heavily deformed crystal, and γ-irradiation increases the fraction having a long mean free path. The measurements support a dynamic (as opposed to static) model of phonon-dislocation interaction.
In Vitro Interaction between a Chloroplast Transit Peptide and Chloroplast Outer Envelope Lipids Is Sequence-specific and Lipid Class-dependent

Interaction of artificial lipid bilayers (liposomes) with the purified transit peptide (SS-tp) of the precursor form of the small subunit for ribulose-2,5-bisphosphate carboxylase/oxygenase (prSSU) has been studied using a vesicle-disruption assay (calcein dye release) and electron microscopy. Employing purified forms of Escherichia coli-expressed prSSU, mature small subunit, glutathione S-transferase-transit peptide fusion protein, and SS-tp in dye release studies demonstrated that lipid interaction is mediated primarily through the transit peptide. Using chemically synthesized peptides (20-mers), the lipid-interacting domain of the transit peptide was partially mapped to the C-terminal 20 amino acids of the transit peptide. Peptides corresponding to other regions of the transit peptide and control peptides promoted significantly less calcein release. Interaction between the transit peptide and the bilayer was very rapid and could not be resolved by stopped-flow fluorometry with a mixing time of <50 ms. Interaction between the peptides and bilayer was also lipid class-dependent. Disruption occurred only when the bilayer contained the galactolipid monogalactosyldiacylglycerol (MGDG). The extent of bilayer disruption directly correlated with the relative concentration of MGDG in the liposome, with maximum calcein release occurring in 20 mol % MGDG liposomes. Lipid bilayers with greater than 20 mol % MGDG could not be achieved as determined by calcein entrapment. Electron microscopy of the liposomes before and after addition of the transit peptide suggested that the transit peptide induced a dramatic reorganization of lipids. These results are discussed in light of a possible mechanism for the early steps in protein transport that may involve polymorphic changes in the envelope membrane organization to include localized non-bilayer HII structures.
Emerging Role for KCNQ1 in Ischemia-Induced Neuronal Death

The slowly activating component of the delayed rectifier potassium current, IKs, composed of KCNQ1-KCNE1 channel subunits, is an important contributor to normal cardiac repolarization. Emerging evidence indicates that KCNQ1 subunits are also expressed in brain, but its precise physiological role in neuronal function has not been investigated. Potassium channels are key players in ischemia-induced death of hippocampal CA1 pyramidal neurons which, in turn, leads to impaired cognition. REST, a gene silencing transcription factor, is up-regulated in global ischemia and contributes to neuronal death. Recently we showed that REST is enriched at the promoter of the KCNQ1 channel and that KCNQ1 mRNA and protein expression are increased in post-ischemic CA1 neurons. Additionally, functional KCNQ1 channels were identified in cultured neurons using KCNQ1-specific inhibitors Chromanol 293B and JNJ-303 and induction of oxygen-glucose deprivation (OGD) induced a marked increase in KCNQ1 currents (∼34%, p > 0.02), evident at 48 h post-ischemia. To assess a possible role for KCNQ1 in ischemia-induced neuronal death, we induced OGD in dissociated hippocampal neurons in the absence and presence of Chromanol 293B (100 µM) and treated with propidium iodine. Inhibition of KCNQ1 markedly diminished cell death, assessed at 24 h (21%, p > 0.002) and 48 h (28%, p > 0.001) suggesting that an up-regulation of KCNQ1 channels may contribute to ischemia-induced neuronal death. To examine a possible role for REST in ischemia-induced up-regulation of KCNQ1, we performed single-locus ChIP which revealed enrichment for REST by ∼2-fold and a decrease in trimethylation of lysine 27 on histone 3 (H3K27me3), an epigenetic mark of gene repression at the KCNQ1 promoter, consistent with the increase in KCNQ1 expression after ischemia. Our findings reveal, for the first time, a role for REST in KCNQ1 expression in response to ischemic insults.
The inhibitor of zeaxanthin formation, dithiothreitol, inhibits blue-light-stimulated stomatal opening in Vicia faba

Dithiothreitol (DTT), an inhibitor of violaxanthin de-epoxidation and zeaxanthin formation in chloroplasts, inhibited blue-light-stimulated stomatal opening in epidermal peels of Vicia faba L. in a concentration-dependent fashion. Complete inhibition was observed at 3 mM DTT. The DTT effect was specific for the stomatal response to blue light, and the red-light-stimulated opening, which depends on photosynthetic reactions in the guard cells, was unaffected. Preirradiation of stomata in epidermal peels with increasing photon fluence rates of red light, prior to an incubation in 10 μmol·m-2·s-1 of blue light and 100 μmol·m-2·s-1 red light, resulted in a DTT-sensitive, blue-light-stimulated opening that was proportional to the fluence rate of the red light pre-treatment. Guard cells in epidermal peels and guard-cell protoplasts irradiated with red light showed increases in their zeaxanthin content that depended on the fluence rate of red light, or on the incubation time. The increases in zeaxanthin concentration were inhibited by DTT. The obtained results indicate that zeaxanthin could function as a photoreceptor mediating the stomatal responses to blue light.
Right median nerve electrical stimulation to hasten awakening from coma

Electrical stimulation of the right median nerve may hasten the awakening of closed head injured, comatose patients. A series of 25 comatose patients have been treated. These patients made better recoveries than similar individuals reported in the literature. In a double-blind pilot project patients in the treated group scored better on interval Glasgow Coma Scale scores, spent fewer days in the intensive care unit, and showed better Glasgow Outcome Scores at 1 month post-injury. Peripheral electrical stimulation of the right median nerve, through activation of the ascending reticular activating system, may be sufficient to arouse the moderate to severely comatose patient.
Bose-Einstein condensation in two dimensions: A quantum Monte Carlo study

A path-integral quantum Monte Carlo method is used to calculate finite temperature properties of up to 1000 hard-core bosons in a two-dimensional isotropic harmonic-oscillator potential. If the interatomic repulsions are sufficiently short range, an abrupt increase in the condensate fraction and a hump in the specific heat occur close to the critical temperature of ideal bosons. The critical temperature and the condensate fraction are in general lowered by an increase in the hard-core radius a. If a is decreased below a certain level, the condensate fraction becomes indistinguishable from the corresponding value of the ideal bosons. For up to 1000 particles, this occurs when ${\mathrm{ln}}^{\ensuremath{-}1}{(1/na}^{2})\ensuremath{\lesssim}0.1,$ where n is the average particle density.
Contrasting water footprints of cities in China and the United States

We examined production and consumption patterns of freshwater, a critical ecosystem service, for selected cities in China and the United States. Ecosystem production of freshwater varies with precipitation and evapotranspiration rates, which are affected by climate, topography, vegetation cover, and soil characteristics. Urban demand for freshwater is spatially distributed due to the location of cities, the variation in the per-capita usage, and the variation in urban population size. To link the spatially heterogeneous patterns of cities and ecosystem service production rates we calculated heterogeneous ecological footprints (HEF) of the land area required to provide urban freshwater needs. We asked, what determines urban freshwater footprint area in cities of the United States and China? Are the same factors operating in the same fashion in both countries? Our results show the strong interaction between population size and local resource production in determining footprint. These results suggest extending the I=PAT identity to include a term describing local ecosystem service productivity in the determination of human impact. By using the ecological footprint methodology in this manner, we can address questions concerning the relationship between social and ecological systems and identify urban-scale constraints to the sustainable withdrawal of a particular ecosystem service. D 2005 Elsevier B.V. All rights reserved.
Strategic Planning with Start-Time Dependent Variable Costs

We present a strategic planning model in which the activities to be planned, such as production and distribution in a supply network, require technology to be installed before they can be performed. The technology improves over time, so that a decision maker has incentive to delay starting an activity to take advantage of better technology and lower operational costs. The model captures the fundamental trade-off between delaying the start time of an activity and the need for some activities to be performed now. Models of this type are used in the oil industry to plan the development of oil fields. This problem is naturally formulated as a mixed-integer program with a bilinear objective. We develop a series of progressively more compact mixed-integer linear formulations, along with classes of valid inequalities that make the formulations strong. We also present a specialized branch-and-cut algorithm to solve an extremely compact concave formulation. Computational results indicate that these formulations can be used to solve large-scale instances, whereas a straightforward linearization of the mixed-integer bilinear formulation fails to solve even small instances.
Microcircuits for attention.

Researchers who study the neuronal basis of cognition face a paradox. If they extract the brain, its cognitive functions cannot be assessed. On the other hand, the brain's microcircuits are difficult to study in the intact animal. In this issue of Neuron , Mitchell et al. make use of a promising approach based on waveform analysis to reveal new details about neuronal interactions during visual attention.
Dual lookup table algorithm: An enhanced method of displaying 16-bit gray-scale images on 8-bit RGB graphic systems

Most digital radiologic images have an extended con­ trast range of 9 to 13 bits, and are stored in memory and disk as 16-bit integers. Consequently, it is difficult to view such images on computers with 8-bit red-green­ blue (RGB) graphic systems. Two approaches have traditionally been used: (1) perform a one-time conver­ sion of the 16-bit image data to 8-bit gray-scale data, and then adjust the brightness and contrast of the image by manipulating the color palette (palette anima­ tion); and (2) use a software lookup table to interac­ tively convert the 16-bit image data to 8-bit gray-scale values with different window width and window level parameters. The first method can adjust image appear­ ance in real time, but some image features may not be visible because of the lack of access to the full contrast range of the image and any region of interest measure­ ments may be inaccurate. The second method allows "windowing" and "leveling" through the full contrast range of the image, but there is a delay after each adjustment that some users may find objectionable. We describe a method that combines palette anima­ tion and the software lookup table conversion method that optimizes the changes in image contrast and brightness on computers with standard 8-bit RGB graphic hardware-the dual lookup table algorithm. This algorithm links changes in the window/level control to changes in image contrast and brightness via palette animation. The purpose of the algorithm is to use palette animation to mimic changes in image appearance performed by the software lookup table method after the window width and window level parameters have changed. The algorithm combines the advantages of both methods: rapid manipulation of image brightness and contrast by palette animation, and the ability to window and level on the full 16-bit image data using the software lookup table. This algorithm may be useful for applications that display 16-bit radiologic images on computers with standard 8-bit RGB graphic systems. Copyright © 1994 by W.B. Saunders Company
On Uniquely Decipherable Codes with Two Codewords

It is shown that every uniquely decipherable code with just two codewords has finite delay. In addition, if a uniquely decipherable code with just two codewords is full, then it is trivial.
gp120-mediated alterations in astrocyte ion transport

The pathogenesis of the acquired immunodeficiency syndrome (AIDS) dementia complex (ADC) is unknown. However, recent work indicates that neurons and astrocytes are functionally compromised by exposure to viral components or cellular factors released from HIV-1-infected macrophages/microglia. We show that exposure of primary cultured rat astrocytes to the major HIV envelope glycoprotein gp120 results in alterations of ion and solute transport that may contribute to neuronal cell injury.
A rigid line inclusion at a bimaterial interface

A solution is presented for the plane elastostatics problem of a rigid line inclusion at a bimaterial interface. Explicit expressions are derived for the complex potentials. The complex stress intensity factors at the tip of the rigid line are compared with those for the corresponding crack problem. It is found that the nature of the singularities differ. Furthermore, unlike the crack problem, the singularity for the rigid line inclusion depends on the stresses parallel to the interface.
Syntheses and characterizations of the in vivo replicative bypass and mutagenic properties of the minor-groove O2-alkylthymidine lesions

Endogenous metabolism, environmental exposure, and treatment with some chemotherapeutic agents can all give rise to DNA alkylation, which can occur on the phosphate backbone as well as the ring nitrogen or exocyclic nitrogen and oxygen atoms of nucleobases. Previous studies showed that the minor-groove O(2)-alkylated thymidine (O(2)-alkyldT) lesions are poorly repaired and persist in mammalian tissues. In the present study, we synthesized oligodeoxyribonucleotides harboring seven O(2)-alkyldT lesions, with the alkyl group being a Me, Et, nPr, iPr, nBu, iBu or sBu, at a defined site and examined the impact of these lesions on DNA replication in Escherichia coli cells. Our results demonstrated that the replication bypass efficiencies of the O(2)-alkyldT lesions decreased with the chain length of the alkyl group, and these lesions directed promiscuous nucleotide misincorporation in E. coli cells. We also found that deficiency in Pol V, but not Pol II or Pol IV, led to a marked drop in bypass efficiencies for most O(2)-alkyldT lesions. We further showed that both Pol IV and Pol V were essential for the misincorporation of dCMP opposite these minor-groove DNA lesions, whereas only Pol V was indispensable for the T→A transversion introduced by these lesions. Depletion of Pol II, however, did not lead to any detectable alterations in mutation frequencies for any of the O(2)-alkyldT lesions. Thus, our study provided important new knowledge about the cytotoxic and mutagenic properties of the O(2)-alkyldT lesions and revealed the roles of the SOS-induced DNA polymerases in bypassing these lesions in E. coli cells.
Optical design by a matrix method

A symmetrical optical system consists of a series of vertex to vertex intervals separating coaxial refracting or reflecting surfaces of revolution. This paper develops two types of matrices composed of constant elements, one representing intervals and the other surfaces. These matrices are multiplied together in the same order as the corresponding intervals and surfaces occur in the optical system. The resultant product matrix expresses the paraxial, aberrational and chromatic behavior of the system.Such a formulation may be applied mechanically by unskilled computers, and suggests a passive electrical network analogue to optical systems. The surfaces are not limited to spheres.
Men, Spirituality, and the Collegiate Experience.

Innovative programs in male spirituality can help college men challenge conventional masculine gender roles and envision creative ways of being men.
A methodology for analysing a repeated measures and survival outcome simultaneously

A considerable body of literature has arisen over the past 15 years for analysing univariate repeated measures data. It is rare in applied biomedical research, however, for interest to be restricted to a single outcome measure. In previous work, Rochon considered the case of bivariate repeated measures data in which each outcome is a discrete or continuous random variable. A GEE model was prescribed to relate each set of repeated measures to important explanatory variables. The 'seemingly unrelated regression' model was then applied to combine the pair of GEE models into an overall analysis framework. In this paper, we extend this approach to the case in which one endpoint is a repeated measures outcome but the second is a survival endpoint. Estimation and hypothesis testing issues are addressed and the methodology is illustrated with an example.
Suppressed cutaneous endothelial vascular control and hemodynamic changes in paretic extremities with edema in the extremities of patients with hemiplegia

Abstract Wang J-S, Yang CF, Liaw M-Y, Wong M-K. Suppressed cutaneous endothelial vascular control and hemodynamic changes in paretic extremities with edema in the extremities of patients with hemiplegia. Arch Phys Med Rehabil 2002;83:1017-23. Objective: To investigate peripheral circulatory function and its underlying mechanisms in the paretic upper extremity after a stroke. Design: Case-control study. Setting: A department of physical medicine and rehabilitation in Taiwan. Participants: A total of 53 hemiplegic patients (28 men, 25 women; mean age ± standard deviation; 58.2±3.8y) were studied. Subjects were divided into edema and nonedema groups. The edema group included 29 hemiplegic patients with edematous paretic upper extremities. Twenty-four hemiplegic patients in the nonedema group did not suffer from limb edema in the paretic upper extremity. Interventions: Not applicable. Main Outcome Measures: Cutaneous microvascular perfusion responses to 3 grade levels of iontophoretically applied 1% acetylcholine (ACh), 1% ACh plus 1% N G -monomethyl-L-arginine (L-NMMA), and 1% sodium nitroprusside (SNP) in the skin of subjects' forearms were determined by laser Doppler perfusion measurements. Moreover, hemodynamic characteristics in the arterial and venous vessels were measured by impedance plethysmography. Results: Resting arterial inflow and venous capacity, tone, and outflow in paretic extremities did not significantly differ from nonparetic extremities, but the hyperemic arterial inflow was lower in paretic extremities than in nonparetic extremities, and paretic extremities were associated with lower ACh- and ACh plus L-NMMA–induced cutaneous perfusions than nonparetic extremities. ACh-induced cutaneous perfusions also decreased much more significantly in edematous paretic extremities than in nonedematous paretic extremities, and skin vascular responses to SNP do not differ significantly between paretic and nonparetic extremities. Conclusion: Cutaneous microcirculatory function in the paretic upper extremity after stroke may be impaired. The impairment may occur because of decreased endothelium-dependent dilation in skin vasculature. Dysfunction in cutaneous microcirculation tends to be more pronounced in the edematous than in the nonedematous extremities. © 2002 by the American Congress of Rehabilitation Medicine and the American Academy of physical Medicine and Rehabilitation