cssi/SciSciGPT-SciSciNet huggingface dataset:
Use of imagery and GIS for humanitarian demining management

In the Fall of 1996, the Center for Geographic Information Science at James Madison University became involved in a project for the Department of Defense evaluating the data needs and data management systems for humanitarian demining in the Third World. In particular, the effort focused on the information needs of demining in Cambodia and in Bosnia. In the first phase of the project one team attempted to identify all sources of unclassified country data, image data and map data. Parallel with this, another group collected information and evaluations on most of the commercial off-the-shelf computer software packages for the management of such geographic information. The result was a design for the kinds of data and the kinds of systems necessary to establish and maintain such a database as a humanitarian demining management tool. The second phase of the work involved acquiring the recommended data and systems, integrating the two, and producing a demonstration of the system. In general, the configuration involves ruggedized portable computers for field use with a greatly simplified graphical user interface, supported by a more capable central facility based on Pentium workstations and appropriate technical expertise.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Co-expression of neuropeptide Y Y1 and Y5 receptors results in heterodimerization and altered functional properties

Abstract Centrally administered neuropeptide Y (NPY) produces anxiolytic and orexigenic effects by interacting with Y1 and Y5 receptors that are colocalized in many brain regions. Therefore, we tested the hypothesis that co-expression of Y1 and Y5 receptors results in heterodimerization, altered pharmacological properties and altered desensitization. To accomplish this, the carboxyl-termini of Y1 and Y5 receptors were fused with Renilla luciferase and green flourescent protein and the proximity of the tagged receptors assessed using bioluminescent resonance energy transfer. Under basal conditions, cotransfection of tagged Y1 receptor and Y5 produced a substantial dimerization signal that was unaffected by the endogenous, nonselective agonists, NPY and peptide YY (PYY). Selective Y5 agonists produced an increase in the dimerization signal while Y5 antagonists also produced a slight but significant increase. In the absence of agonists, selective antagonists decreased dimerization. In functional studies, Y5 agonists produced a greater inhibition of adenylyl cyclase activity in Y1/Y5 cells than cells expressing Y5 alone while NPY and PYY exhibited no difference. With PYY stimulation, the Y1 antagonist became inactive and the Y5 antagonist exhibited uncompetitive kinetics in the Y1/Y5 cell line. In confocal microscopy studies, Y1/Y5 co-expression resulted in increased Y5 signaling following PYY stimulation. Addition of both Y1 and Y5 receptor antagonists was required to significantly decrease PYY-induced internalization. Therefore, Y1/Y5 co-expression results in heterodimerization, altered agonist and antagonist responses and reduced internalization rate. These results may account for the complex pharmacology observed when assessing the responses to NPY and analogs in vivo .
Digital Preservation Challenges with an ETD Collection — A Case Study at Texas Tech University

Abstract The dangers that digital files face can seem merely the stuff of theory and risk assessment matrices until an institution experiences its first data loss; especially when those digital files represent the graduate research output of a university, the potential impact of that loss increases exponentially. The authors present a case study of the challenges one academic library has encountered in the stewardship of its electronic theses and dissertations (ETDs) over the course of a decade. This article examines the problems that can arise years after the transition from a physical to electronic collection and presents documentation solutions that can make ETD preservation and curation more effective.
Ionic galleries: a bilayered host-guest cocrystal of C-propyl pyrogallol[4]arene with an ionic liquid.

We report on a cocrystal between C-propyl pyrogallol[4]arene and the ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate exhibiting a remarkable bilayer topology comprising two unique host–guest complexes resulting from the ionic liquid cation binding in two distinctive orientations relative to the macrocycle.
Effects of Rotation on Heat Transfer for a Single Row Jet Impingement Array With Crossflow

The effects of the Coriolis force are investigated in rotating internal serpentine coolant channels in turbine blades. For complex flow in rotating channels, detailed measurements of the heat transfer over the channel surface will greatly enhance the blade designers’ ability to predict hot spots so coolant may be distributed more effectively. The present study uses a novel transient liquid crystal technique to measure heat transfer in a rotating, radially outward channel with impingement jets. A simple case with a single row of constant pitch impinging jets with the crossflow effect is presented to demonstrate the novel liquid crystal technique and document the baseline effects for this type of geometry. The present study examines the differences in heat transfer distributions due to variations in jet Rotation number, Roj , and jet orifice-to-target surface distance (H/dj = 1,2, and 3). Colder air, below room temperature, is passed through a room temperature test section to cause a color change in the liquid crystals. This ensures that buoyancy is acting in a similar direction as in actual turbine blades where walls are hotter than the coolant fluid. Three parameters were controlled in the testing: jet coolant-to-wall temperature ratio, average jet Reynolds number, Rej , and average jet Rotation number, Roj . Results show, such as serpentine channels, the trailing side experiences an increase in heat transfer and the leading side experiences a decrease for all jet channel height-to-jet diameter ratios (H/dj ). At a jet channel height-to-jet diameter ratio of 1, the crossflow from upstream spent jets greatly affects impingement heat transfer behavior in the channel. For H/dj = 2 and 3, the effects of the crossflow are not as prevalent as H/dj = 1: however, it still plays a detrimental role. The stationary case shows that heat transfer increases with higher H/dj values, so that H/dj = 3 has the highest results of the three examined. However, during rotation the H/dj = 2 case shows the highest heat transfer values for both the leading and trailing sides. The Coriolis force may have a considerable effect on the developing length of the potential core, affecting the resulting heat transfer on the target surface.
Drug-Eluting Fibers for HIV-1 Inhibition and Contraception

Multipurpose prevention technologies (MPTs) that simultaneously prevent sexually transmitted infections (STIs) and unintended pregnancy are a global health priority. Combining chemical and physical barriers offers the greatest potential to design effective MPTs, but integrating both functional modalities into a single device has been challenging. Here we show that drug-eluting fiber meshes designed for topical drug delivery can function as a combination chemical and physical barrier MPT. Using FDA-approved polymers, we fabricated nanofiber meshes with tunable fiber size and controlled degradation kinetics that facilitate simultaneous release of multiple agents against HIV-1, HSV-2, and sperm. We observed that drug-loaded meshes inhibited HIV-1 infection in vitro and physically obstructed sperm penetration. Furthermore, we report on a previously unknown activity of glycerol monolaurate (GML) to potently inhibit sperm motility and viability. The application of drug-eluting nanofibers for HIV-1 prevention and sperm inhibition may serve as an innovative platform technology for drug delivery to the lower female reproductive tract.
Comparative study of Fe-C bead and graphite target performance with the National Ocean Science AMS (NOSAMS) facility recombinator ion source

Abstract An accelerator mass spectrometry (AMS) experiment was designed to investigate 14 C target performance for two target types over a range of isotopic concentrations and sample sizes, with a special focus on the ability to measure 14 C in environmental samples having only microgram amounts of carbon. The findings were positive, showing that precision, accuracy, and stability were adequate to determine 14 C to 1% or better in samples containing as little as 25 μg carbon. Satisfactory Poisson uncertainty and target stability were demonstrated down to a level of 7 μg carbon, but experimental data showed that accurate measurements at that level require detailed knowledge of blank variability and mass dependence of the modern carbon calibration factor.
Kinetic Modeling and Measurement of Active Species Distributions during Dry Etching

Abstract : A simple kinetic dry etching model accounting for generation, loss, and transport of the reactive and by-product species is developed. To demonstrate and evaluate the model, the etching of silicon using sulfur hexafluonde + oxygen + argon in the plasma etch mode is investigated. Keywords: Silicon.
Thin film module fabrication and reliability advances

Abstract This paper presents the Chronar experience of deploying amorphous silicon (a-Si) modules in the field and the resulting efforts to understand and correct observed degradation mechanisms. The data were obtained from several on-site observations, and evaluation and analysis of corrosion effects in a-Si modules. These data are correlated with laboratory tests, and a design for a new a-Si module is proposed.
Observation of a tilted Gaussian beam on the 7ID beamline of the advanced photon source

Abstract An experimenter using an undulator beamline expects a Gaussian beam profile in two dimensions. Using a pinhole camera, one can measure the source size and orientation. With a camera placed far away from the source, one can measure the beam profile and estimate the source divergence. The camera can also reveal a possible tilt of the beam. In late 2005, we observed a tilt of 7 ∘ on the beam profile of the 7ID beamline, 51.5 m from the source at the Advanced Photon Source (APS). A pinhole camera measurement revealed a source tilt of only about 1 ∘ . These two separate measurements implied a tilt in the divergence of the beam. The source and divergence tilts may vary for each source point of the APS. We will discuss the implication of these tilts on the performance of an insertion device beamline at the APS.
Psychopathology and Trauma in Epileptic and Psychogenic Seizure Patients

Forty-one patients admitted to an inpatient epilepsy unit for intractable seizures were evaluated for the presence of Axis I and Axis II diagnoses and for a history of trauma by use of a structured clinical interview. Both the interviewer and the patient were blind to the seizure diagnosis. Following video and electroencephalographic evaluation, 27 patients were diagnosed with epileptic seizures, and 14 had psychogenic seizures. The history of Axis I and Axis II disorders did not distinguish the two groups of patients. A history of trauma was significantly more likely in the patients with psychogenic seizures. The experience of trauma appears to be an important factor in the de-velopment of psychogenic seizures. Sexual trauma alone, however, was not significantly associated with psychogenic seizures.
Increasing expression of H- or L-ferritin protects cortical astrocytes from hemin toxicity.

Iron toxicity may contribute to oxidative injury in cells surrounding an intracerebral hematoma. Cells detoxify iron by sequestering it in ferritin, a 24-mer heteropolymer constructed of H and L subunits. The relative antioxidant efficacy of H and L-ferritin has not been defined, and was tested in this study using an established model of hemin toxicity. Consistent with prior observations, cultures treated with 30 μM hemin sustained loss of approximately half of cells by six hours, as measured by LDH and MTT assays, and a 14-fold increase in protein carbonyls. Increasing expression of either ferritin by adenoviral gene transfer prior to hemin treatment had a similar protective effect. Quenching of calcein fluorescence, a marker of the labile iron pool, in hemin-treated cultures was also equally reduced by either subunit. These results suggest that over-expression of either H or L ferritin protects astrocytes from hemin, and may be beneficial after CNS hemorrhage.
Neuropsychological Functioning in Preschool-age Children with Sickle Cell Disease: The Role of Illness-related and Psychosocial Factors

Cognitive and academic deficits have been identified in school-aged children with sickle cell disease (SCD). However, there have been very few identified studies that examine neuropsychological functioning in preschool-age children with SCD. It is important to understand effects of SCD from a developmental perspective and to consider the contribution of environmental factors in this at-risk population. Neuropsychological functioning of preschool-age children with SCD and no history of overt stroke (n = 26) was examined across several domains (language, immediate memory/brief attention, visuospatial/visuoconstructional, motor/visuomotor). The mean Full Scale IQ for the sample was 89.0. Performance on the Immediate Memory/ Brief Attention domain was significantly higher than the other domains, although the pattern of performance was relatively consistent, with mean standard scores ranging from 88.0 to 95.0. Disease severity was not significantly related to cognitive functioning in this group of young childr...
Age dependent changes in aversive responses of mice to ethanol and their correlation with life duration

Abstract Age dependent changes in voluntary responses to an ethanol solution were observed in CF1 male control mice, and an experimental group provided 5% sucrose (w/v) as their only liquid for ten days beginning at the age of four weeks. This was a life duration study that began when the mice were ten weeks of age. An untreated group of C57/B1 mice was similarly observed. A 3% ethanol solution (v/v) was offered the CF1 mice, and for a comparable demonstration of aversion to ethanol in C57/B1 mice, an 18% ethanol solution was required. In all three groups, the curves of decreasing proportions of behaviorally aversive mice that occurs with advancing age closely parallels the survivorship curves. In the CF1 experimentals a more rapid development of behavioral aversion during the early portion of the life cycle, and an earlier onset of its decline phase occurs. Mean life span was significantly shorter in this group than in controls. The age dependent changes in another parameter, total fluid intake per gram body weight, were compared for short-lived and long-lived subgroups of the C57/B1 mice. This ratio is relatively high early in life, decreases to significantly lower levels in adulthood, and later increase with advancing age. In the short-lived contingent lowest values are attained around the age of 40 weeks compared to 100 weeks in long-lived mice; and the subsequent phase of increasing values is similarly shifted.
Changes in the thermal characteristics of hypothalamic neurons during sleep and wakefulness

The characteristics of the mammalian thermoregulatory system are dependent upon arousal state. During NREM sleep thermoregulatory mechanisms are intact but body temperature is regulated at a lower level than during wakefulness. In REM sleep thermoregulatory effector mechanisms are inhibited and thermal homeostasis is severely disrupted. Thermosensitivity of neurons in the preoptic/anterior hypothalamus (POAH) was determined for behaving kangaroo rats (Dipodomys deserti) during electrophysiologically defined wakefulness, NREM sleep and REM sleep to elucidate possible neural mechanisms for previous findings of state-dependent changes in thermoregulation. Thirty cells were tested during at least two arousal states. During wakefulness, 70% of the recorded cells were sensitive to changes in local temperature, with the number of warm-sensitive (W) cells outnumbering cold-sensitive (C) cells by 1.6:1. In NREM sleep, 43% of the cells were thermally sensitive, with the ratio of W:C remaining the same as in wakefulness. In REM sleep only two cells were thermosensitive (both W). The decrease in neuronal thermosensitivity of POAH cells during REM sleep parallels findings of inhibition of thermoregulatory effector responses during REM, although further work is necessary to determine the source and nature of the inhibition.
The timing of bedtime and waketime decisions in free-running subjects.

Twelve “free-running’ temporal isolation studies were performed using healthy human subjects aged 20–81 years (4 males, 8 females). Circadian rhythms were measured in subjective alertness (using a visual analogue scale technique) and rectal temperature. In all 12 subjects best fitting rhythm periods were found to be shorter for rectal temperature (mean = 24.3 hours) than for subjective alertness (mean = 24.8 hours). Both rhythms were predictive of bedtime and waketime decisions. Bedtime decisions tended to cluster on the falling arm of the temperature and alertness cycles (modal times = 120 degrees (temperature) and 140 degrees (alertness) after acrophase); waketime decisions on the rising arm (modal times = 240 degrees (temperature) and 300 degrees (alertness) after acrophase). When this pattern was violated, sleep episodes were significantly more variable in length and disturbed by intruding wakefulness.
Basic needs and human rights

Abstract This paper discusses the relationship between basic needs and human rights and addresses such questions as: is the satisfaction of basic needs a human right? or, are human rights themselves basic needs? are there basic needs other than material needs which embrace human rights? do the respect for rights and the satisfaction of needs go together or car there be conflict? The paper attempts to distinguish between a variety of ‘rights’ — positive, negative; social, economic, political, civil — and to clarify the best means by which to achieve maximum fulfilment of these ‘rights’.
Earlier (late Pliocene) first appearance of the Caribbean reef-building coral Acropora palmata: Stratigraphic and evolutionary implications

An integrated stratigraphic study of reefal deposits on the Caribbean side of the Isthmus of Panama (Limon, Costa Rica) has discovered a significantly earlier first appearance of the major reef-building coral Acropora palmata . A. palmata is here reported from the early late Pliocene, constrained in age to within the Gauss chron (ca. 3.6–2.6 Ma). This coral was previously thought to have originated in the earliest Pleistocene and has subsequently been used as a Quaternary marker throughout the Caribbean and the Bahamas. An earlier appearance in the southern Caribbean implies a diachronous first appearance datum relative to the northern Caribbean. This older age also places A. palmata well within the transition phase of a Pliocene (4–1 Ma) faunal turnover that was marked by widespread extinction and origination of Caribbean coral species. An early late Pliocene origination is coincident with formation of the Isthmus, climate reorganization, and frequent sea-level changes associated with onset of Northern Hemisphere glaciations. The rapid growth and accumulation rates that characterize A. palmata may therefore be adaptive to these fluctuating environmental conditions, enabling its success during the subsequent Pleistocene glacial cycles.
Asymptotic expansions for Markov processes with lévy generators

This paper considers a deterministic flow inn-dimensional space, perturbed by a Markov jump process with small variance. Asymptotic expansions are obtained for certain functionals of Feynman—Kac type, in powers of a small parameter representing a noise intensity. The methods are analytical rather than probabilistic.
Imported machinery and growth in LDCs

Abstract This paper finds evidence in favor of the claim that imported machinery leads to higher growth in developing countries. Using panel data, we find that investment in domestically produced equipment reduces the growth rate while investment in imported equipment increases it. The advantage of this study over the paper of Lee [Journal of Development Economics, 48 (1) (1995) 91] is that since we make a distinction between imported and domestically produced equipment, we are able to distinguish our hypothesis from the DeLong and Summers hypothesis that equipment investment in general contributes more to growth.
Inversion Domain and Stacking Mismatch Boundaries in GaN.

We present first-principles calculations of domain wall energies for inversion domain boundaries and stacking mismatch boundaries in GaN. We find a low-energy inversion domain boundary in which each atom remains fourfold coordinated without the formation of Ga-Ga or N-N bonds. This boundary, denoted IDB*, does not induce electronic states in the band gap and would therefore not adversely impact photoluminescence efficiency. The stacking mismatch boundary has a higher formation energy than IDB*, and gives rise to occupied N-derived interface states in the band gap.
Using X-rays to characterize the process of self-assembly in real time

Abstract We have performed in situ X-ray reflectivity studies of the growth of octadecyltrichlorosilane (OTS) monolayers on oxidized Si(111) from solutions in heptane. We find that for all concentrations, the film grows through the formation of islands of vertical molecules. The coverage follows a simple Langmuir form as a function of time, except for very low concentration solutions at early times, where a time offset is required to fit the curve. We have also examined films removed from solution, and we find that rinsing removes molecules and causes the remaining molecules to tilt. Thus, samples studied using the ‘interrupted growth’ technique are not representative of the actual growth process.
The relationship between GARCH and symmetric stable processes: Finding the source of fat tails in financial data

Abstract Several studies find the empirical characteristics of financial data to be consistent with stable Paretian distributions, while several other studies find the empirical characteristics to be consistent with GARCH models. In this paper we establish that in situations common in finance, many of the properties of stable models are shared by GARCH models, implying that many of the findings of fat-tailed stable distributions in finance since Mandelbrot (1963) could be caused by temporal clustering of volatility. We also identify some properties that these two models do not have in common, and use these to distinguish between the models. We apply our results to eight financial data series, and conclude that the GARCH model characterizes the data better than the stable Paretian model. This supports the hypothesis that the fat tails in financial data are better described as being caused by volatility clustering than by a stable Paretian data generating process.
Inducible, reversible, and stable RNA interference in mammalian cells

RNA interference is a powerful genetic approach for efficiently silencing target genes. The existing method of gene suppression by the constitutive expression of short hairpin RNAs (shRNAs) allows analysis of the consequences of stably silencing genes but limits the analysis of genes essential for cell survival, cell cycle regulation, and cell development. We have developed an inducible U6 promoter for synthesis of shRNAs in both human and murine cells. Cells containing stably integrated shRNA expression constructs demonstrate stringent dosage- and time-dependent kinetics of induction with undetectable background expression in the absence of the inducer ecdysone. Inducible suppression of human p53 in glioblastoma cells shows striking morphological changes and defects in cell cycle arrest caused by DNA damage, as expected. Remarkably, the inducibility is reversible after withdrawal of the inducer, as observed by reappearance of the protein and a restoration of the original cell phenotype. Inducible and reversible regulation of RNA interference has broad applications in the areas of mammalian genetics and molecular therapeutics.
Concanavalin A in vivo: induction of hemorrhagic skin lesions (Arthus-like reactions) in mice.

Concanavalin A injected into the skin of mice induced the formation of hemorrhagic Arthus-like lesions. No lesions resulted if concanavalin A was adsorbed with insoluble a2 - macroglobulin or if mice were first treated with nitrogen mustard. The ability of concanavalin A, phytohemagglutinin, or pokeweed mitogen to induce skin lesions seemed to parallel their ability to precipitate serum proteins.
CHAPTER 2: Preparing Urban Educators for the Twenty-First Century

ABSTRACT This chapter provides a review of the research related to preparing teachers for urban settings. Specific competencies requisite to the successful preparation of urban teachers are presented, along with the research base supporting these competencies. The authors argue that teacher preparation program features that support the development of these competencies would contribute to a renaissance in teacher education.
Local superconductivity in ultrathin Sn films.

The thickness dependence of superconductivity has been investigated in ultrathin Sn films near the threshold for normal-state conduction. An evolution from insulating to metallic superconducting behavior is observed with increasing thickness and decreasing sheet resistance. A striking feature of the data is the observation of quasireentrant superconductivity which may be a consequence of the existence of local rather than global superconducting order.
Forest cover change patterns in Myanmar (Burma) 1990-2000.

Myanmar is one of the most forested countries in mainland South-east Asia. These forests support a large number of important species and endemics and have great value for global efforts in biodiversity conservation. Landsat satellite imagery from the 1990s and 2000s was used to develop a countrywide forest map and estimate deforestation. The country has retained much of its forest cover, but forests have declined by 0.3% annually. Deforestation varied considerably among administrative units, with central and more populated states and divisions showing the highest losses. Ten deforestation hotspots had annual deforestation rates well above the countrywide average. Major reasons for forest losses in these hotspots stemmed from increased agricultural conversion, fuelwood consumption, charcoal production, commercial logging and plantation development. While Myanmar continues to be a stronghold for closed canopy forests, several areas have been experiencing serious deforestation. Most notable are the mangrove forests in the Ayeyarwady delta region and the remaining dry forests at the northern edge of the central dry zone.
Diagnostic accuracy of conventional and cholangioscopy-guided sampling of indeterminate biliary lesions at the time of ERCP: a prospective, long-term follow-up study.

Background The diagnostic accuracy of cholangioscopy-guided sampling has not been rigorously evaluated. Objective To prospectively evaluate the accuracy of cholangioscopy-guided mini-forceps sampling and compare it with standard cytology brushings and forceps biopsies for the tissue diagnosis of indeterminate biliary lesions. Design Prospective, long-term follow-up, paired design cohort study. Setting Tertiary center. Patients Patients undergoing cholangioscopy for the evaluation of indeterminate biliary lesions. Interventions Each patient underwent triple sampling with cholangioscopy-guided mini-forceps, cytology brushing, and standard forceps. Main Outcome Measurements Diagnostic accuracy of each sampling method compared with the patient final status (cancer vs no cancer). Results A total of 26 patients (17 cancer positive/9 cancer negative) were enrolled. The mean follow-up in the patients with no cancer was 21.78 (SD ±6.78) months. The procedure was technically successful in all cases (100%). Sample quality was adequate in 25 of 26 (96.2%) of the cytology brushings, in 26 of 26 (100%) of the standard forceps biopsies, and in 25 of 26 (96.2%) of the mini-forceps biopsies. The sensitivity, accuracy, and negative predictive values were 5.9%, 38.5%, and 36% for standard cytology brushings; 29.4%, 53.8%, and 42.8% for standard forceps biopsies; and 76.5%, 84.6%, and 69.2% for mini-forceps biopsies, respectively. When comparing the 3 methods of sampling, mini-forceps biopsy provided significantly better sensitivity and overall accuracy compared with standard cytology brushing ( P P = .0215). Limitations Potential for selection bias. Conclusions Cholangioscopy-guided biopsies of indeterminate biliary lesions have significantly higher accuracy compared with ERCP-guided cytology brushings and standard forceps biopsies, but negative findings on mini-forceps biopsy cannot rule out malignancy with a high degree of certainty. (Clinical trial registration number: NCT01227382.)
Low Complexity Decoder Architecture for Low-Density Parity-Check Codes

In this paper, we propose a low complexity decoder architecture for low-density parity-check (LDPC) codes using a variable quantization scheme as well as an efficient highly-parallel decoding scheme. In the sum-product algorithm for decoding LDPC codes, the finite precision implementations have an important tradeoff between decoding performance and hardware complexity caused by two dominant area-consuming factors: one is the memory for updated messages storage and the other is the look-up table (LUT) for implementation of the nonlinear function ?(x). The proposed variable quantization schemes offer a large reduction in the hardware complexities for LUT and memory. Also, an efficient highly-parallel decoder architecture for quasi-cyclic (QC) LDPC codes can be implemented with the reduced hardware complexity by using the partially block overlapped decoding scheme and the minimized power consumption by reducing the total number of memory accesses for updated messages. For (3, 6) QC LDPC codes, our proposed schemes in implementing the highly-parallel decoder architecture offer a great reduction of implementation area by 33% for memory area and approximately by 28% for the check node unit and variable node unit computation units without significant performance degradation. Also, the memory accesses are reduced by 20%.
Simple probability models for project contracting

There are two aspects to the process of price setting using sealed bids. The project owner is interested in deploying the contract mechanism that will secure reliable service at the cheapest cost. On the other hand, each contractor bidding for the project is interested in winning the contract but at a price that assures him a reasonable profit margin. We use a parsimonious stochastic model to compare and contrast some commonly used contracts from the point of view of the project owner. We show that if the bidders are risk neutral, a Fixed Price contract results in the smallest expected procurement cost for the project owner. We introduce and analyze Menu contracts and show that the expected price of a Menu contract lies in between the prices of the Fixed Price and Cost Plus contracts for the same project. We analyze how risk aversion and collusion, which we model using concepts of stochastic dependence, impacts the average winning bid price.
An analysis of the effect of residual stresses on deformation and damage mechanisms in AlSiC composites

Abstract The effect of thermally induced residual stresses on the mechanical properties and ductility of AlSiC composites was investigated numerically. The predicted behavior in uniaxial loading was calculated with and without the inclusion of the residual stresses which result from the mismatch in thermal expansion between aluminum and SiC. In this analysis, void nucleation by interfacial debonding at the whiskers' ends was assumed to be the limiting failure mechanism. Two cases, both with a fiber volume fraction of 20% and fiber aspect ratio of 4, but with different fiber spacings, were considered. The residual stresses had a small effect on the predicted ductility of the composite, even when a relatively weak interface strength was assumed. The residual stresses are shown to redistribute as interfacial failure is approached. A close end-to-end fiber spacing gives a greater flow strength in compression than in tension and the residual stresses which arise during thermomechanical processing tend to enhance this effect.
Tensile ductility of several commercial aluminum alloys at elevated temperatures

One experimental and five commercial aluminum alloys were tested in tension at elevated temperatures (225 °C to 500 °C) over a range of strain rates (2×10−5 to 10−1 s−1). The experimental alloy contained 5 wt pct Zn with a balance of Al. The commercial alloys included AA 5182, 5754, 7150, 6111, and 6022. Two 5182 materials were examined, one produced by standard ingot-processing methods and the other by continuous casting. The 5754 and 5182 alloys exhibited a deformation regime consistent with solute-drag creep for values of diffusivity-compensated strain rate less than 1013 m−2. Within this regime, the 5754 and ingot-metallurgy 5182 materials exhibited tensile ductilities up to 140 pct. The continuously cast 5182 material exhibited lower ductility in this regime than the 5754 and ingot-metallurgy 5182 materials, despite similar stress exponents. Ductility was reduced in the continuously cast 5182 because of significant dynamic grain growth and cavitation. The 7150, Al-5Zn, 6111, and 6022 materials exhibited significantly higher stress exponents and lower tensile ductilities than the 5000-series materials.
The Relationship Between Racial Identity Status Attitudes and Acculturation Among Chinese and Korean Americans: A Criterion Profile Analysis

This study tested the relationship between racial identity and acculturation among 223 Asian Americans self-identifying as Chinese American or Korean American. Findings showed within-group variations among the study participants with regard to their racial identity status attitudes and acculturation. Using criterion profile analysis, the authors found 2 distinctive criterion profiles of racial identity status attitudes that significantly related to higher levels of acculturation among Chinese American and Korean American participants. Implications for multicultural counseling, racial identity, and acculturation research are discussed. Este estudio puso a prueba la relacion entre identidad racial y aculturacion entre 223 individuos asiatico-americanos que se identifican a si mismos como chino-americanos o coreano-americanos. Los resultados mostraron variaciones dentro del miso grupo entre los participantes del estudio en cuanto a su aculturacion y sus actitudes hacia el estatus de su identidad racial. Usando un analisis de perfil de criterio, los autores encontraron 2 perfiles de criterio distintivos para las actitudes hacia el estatus de identidad racial que estaban relacionados significativamente con niveles mas altos de aculturacion entre los participantes chino-americanos y coreano-americanos. Se discuten las implicaciones para investigaciones sobre consejeria multicultural, identidad racial y aculturacion.
The statistical summation of weak flux-line pins in type II superconductors

A random array of flux-line-pinning defects is shown to produce instabilities in the flux-line lattice and a significant bulk pinning-force density even if the pins individually fail to satisfy the threshold criterion. A simplified model defect-flux-line interaction is used to obtain approximate expressions for the critical pinning-force densityF c.The theory predicts that in materials with a dilute array of weak pinsF cdepends only weakly on magnetic field except within narrow peaks near the upper and lower critical fields. The width of the peaks increases as the pins are made denser or stronger. A broad, dome-shaped peak inF cand scaling-law behavior, both of which are usually associated with large-F cmaterials, is the strong-pinning limit of this theory. This limit may be reached either by making the pins very strong or very dense. The results forF cagree at least qualitatively with a number of experimental observations.
Behaviourism: The Bane of School Mathematics.

This paper discusses the role behaviourism is playing in the current development of school mathematics. A discussion of the underlying philosophy and wide‐spread use of behaviourism concludes with the recommendation that the behaviouristic model should not be used in constructing mathematics curricula. The behaviouristic approach to education seems appropriate only for those aspects of a curriculum which are concerned with skill development. Behaviourism equates training with education, and a blanket adoption of such a philosophy for all of school mathematics misses the heart and essence of the mathematics discipline. This paper argues against embedding mathematics curricula within the behaviouristic framework, and thus presents a plea for us to re‐evaluate the objectives of school mathematics.
MODIS Level 1B calibration and data products

The Moderate Resolution Imaging Spectroradiometer (MODIS) is an Earth-viewing sensor that is currently operating on the EOS-Terra and EOS-Aqua satellites. Each MODIS instrument has 36 bands. Data are received from 490 detectors in these reflective Solar and infrared emissive bands. Calibration of the 490 channels on each MODIS instrument is performed by the MODIS Characterization Support Team (MCST), which works closely with the members of the MODIS Science Team to provide a calibration product that is useful for their geophysical products. The MODIS Level 1B (L1B) algorithm performs radiometric calibration for the duration of each mission. The L1B input files, output data products, and the emissive and reflective calibration algorithms are described. The Look-up Tables (LUTs) that provide the instrument characterization needed to run the L1B software are also described. We briefly present the L1B code standards, properties, and enhancement process. Lastly, "lessons learned" are discussed.
Effect of Marginal Zinc Deficiency on Human Growth and Development

Growth and development disorders in humans caused by zinc (Zn) deficiency have been investigated for a long time. Although marginal Zn deficiency is a common nutritional problem around the world, especially in the children of developing countries where diets have less Zn available, it is difficult to identify. This review provides the progression of studies in the effect of Zn deficiency on human growth and development, and also explains the possible mechanisms of how Zn promotes these phenomena. These mechanisms involve the effects of Zn on DNA synthesis, RNA synthesis, and cell division. The concept of zn-finger proteins explains the role of Zn in gene expression and endocrine function. Findings indicate that Zn deficiency can result in delayed growth and development which can be corrected in part by Zn supplementation.
15-Deoxy-Δ12,14-prostaglandin J2 regulates mesangial cell proliferation and death

15-Deoxy-Δ 12,14 -prostaglandin J 2 regulates mesangial cell proliferation and death. Background Proliferation of intrinsic glomerular cells is a common response to renal injury. Acutely, proliferation may be beneficial, but sustained glomerular hypercellularity after injury is associated with progressive renal failure. To identify endogenous factors that may be responsible for regulating glomerular cell number, the effects of J-series cyclopentenone prostaglandins (PGs) on human glomerular mesangial cell proliferation and death were examined. Methods Human mesangial cells were grown in the presence or absence of PGJ 2 or its metabolite 15-Deoxy-Δ 12,14 -PGJ 2 (15dPGJ 2 ). The number of viable cells was measured by the reduction of the tetrazolium MTS to a colored formazan product. Apoptosis was assessed by caspase-3 activation and DNA fragmentation. Results PGJ 2 at concentrations up to 10 μmol/L caused mesangial proliferation. 15dPGJ 2 also caused mesangial proliferation at low concentrations (≤2.5 μmol/L), but induced mesangial cell death at higher concentrations (>5 μmol/L). Cell death occurred in part through apoptosis, measured as an increase in caspase-3 activity and DNA fragmentation in 15dPGJ 2 -treated cells. Cell death was associated with a decline in baseline phosphorylation of the survival factor Akt and increased Akt degradation, whereas 15dPGJ 2 -induced mesangial proliferation was blocked by inhibition of the PI 3-kinase/Akt pathway. 15dPGJ 2 is a potent PPARγ agonist. Like 15dPGJ 2 , treatment of mesangial cells with thiazolidinedione-type PPARγ ligands (10 to 20 μmol/L) caused significant cell death, but at lower concentrations also caused a small degree of proliferation. Conclusions J-series prostaglandins thus may be involved in the initiation of glomerular hypercellularity through Akt-dependent proliferation, and restoration of normal glomerular architecture through PPARγ-mediated apoptosis. Manipulation of these prostaglandins may be relevant to the treatment of progressive glomerular disease.
Crystallization and preliminary X-ray diffraction studies of the abscisic acid receptor PYL3 and its complex with pyrabactin.

Abscisic acid (ABA) modulates many developmental processes and responses to environmental stress. Recently, a family of pyrabactin resistance-like proteins (PYLs) in Arabidopsis thaliana were identified to be abscisic acid receptors. Although the 14 PYLs members share a similar sequence identity, they exhibit different responses toward pyrabactin. Apo-PYL3 is a dimer; however, its oligomeric state changes greatly on the addition of pyrabactin. Moreover, pyrabactin binds dimeric PYL3 in a nonproductive mode which prevents receptor activation and inhibition of PP2Cs. Here, the expression, purification and crystallization of apo-PYL3 and of PYL3 complexed with pyrabactin are reported. Diffraction data were optimized to 2.5 A resolution for apo-PYL3 and to 1.83 A resolution for PYL3–pyrabactin. The crystals of apo-PYL3 and PYL3–pyrabactin belonged to space groups P41212 and P212121, respectively.
CROSS-NATIONAL CRIME DATA: SOME UNADDRESSED PROBLEMS

ABSTRACT Questions regarding the quality and comparability of cross-national crime data from different sources have cast doubt on the validity of explanatory cross-national research on crime. While past research has addressed some of the important issues, other problems remain that have not been adequately addressed Data sources differ in the types of crime for which rates are available, rates for the same nation for the same type of crime, and the sample composition of nations for which rates are available. This research examines whether these differences affect explanatory cross- national research on crime in terms of the association of relevant independent variables with crime rates. Results show that choice of data source affects the associations of relevant independent variables to homicide rates and that these associations also differ depending on whether robbery or other types of theft is studied Recommendations are made on choice of rates and data sources for future research.
Effects of diabetes on the vascular system: current research evidence and best practice recommendations

Diabetes mellitus has been referred to as a vascular disease because of its effect on the vascular endothelial wall. In recent years, research has identified specific effects of hyperglycemia and insulin resistance on the vasculature of the diabetic patient. Atherosclerosis is known to develop earlier in the diabetic patient and is more aggressive due to the metabolic effects of hyperglycemia and insulin resistance. The results of many large, randomized, prospective trials have provided practice changes in the management of the patient with diabetes. Trials such as the Framingham Study identified risk factors associated with atherosclerosis. Additional studies, such as the Diabetes Control and Complications Trial and the United Kingdom Prospective Diabetes Study, provided information about risk factors for diabetes and contributed to treatment recommendations for the person with type 1 or type 2 diabetes. Results of these and many other trials continue to change the recommendations for the person with diabetes to reduce mortality and prevent coronary heart disease, blindness, renal failure, and amputation. This paper will identify the effects of diabetes on the vascular system and outline best practice recommendations on the basis of clinical trials.
Results of Non-operative and Operative Management Of Apophyseal Avulsion Fractures of the Hip and Pelvis in Adolescent Athletes

Objectives:Apophyseal avulsion fractures of the hip and pelvis occur almost exclusively in the adolescent population, with greater numbers being seen recently as the popularity and intensity of you...
CHANGING PERSPECTIVES ON SQUATTER SETTLEMENTS, INTRAURBAN MOBILITY, AND CONSTRAINTS ON HOUSING CHOICE OF THE THIRD WORLD URBAN POOR

Accelerated rates of growth of Third World cities in the last 30 years has produced several uncontrolled processes: mass in-migration, mushrooming squatter settlements, and virtual anarchy in the urban land and housing spheres. This review documents the vacillating opinions, perspectives, policies, and evaluations of the changes taking place during this contemporary phase of uncontrolled urbanization. We appear to know more now than when these processes first attracted attention, but the record emerges far from complete or satisfactory. Specifically, a preoccupation with housing provision has ignored what appears to be the more crucial issue, the creation of a sufficient supply of developed and appropriately located land to meet the housing space requirements of the Third World urban poor.
A Confirmatory Study of Rating Scale Category Effectiveness for the Coaching Efficacy Scale.

This study extended validity evidence for measures of coaching efficacy derived from the Coaching Efficacy Scale (CES) by testing the rating scale categorizations suggested in previous research. Previous research provided evidence for the effectiveness of a four-category (4-CAT) structure for high school and collegiate sports coaches; it also suggested that a five-category (5-CAT) structure may be effective for youth sports coaches, because they may be more likely to endorse categories on the lower end of the scale. Coaches of youth sports (N = 492) responded to the CES items with a 5-CAT structure. Across rating scale category effectiveness guidelines, 32 of 34 evidences (94%) provided support for this structure. Data were condensed to a 4-CAT structure by collapsing responses in Category 1 (CAT-1) and Category 2 (CAT-2). Across rating scale category effectiveness guidelines, 25 of 26 evidences (96%) provided support for this structure. Findings provided confirmatory, cross-validation evidence for both t...
Aromatic Reduced Amide Bond Peptidomimetics as Selective Inhibitors of Neuronal Nitric Oxide Synthase

Nitric oxide synthase inhibitors could act as important therapies for disorders arising from overstimulation or overexpression of individual nitric oxide synthase (NOS) isoforms. But preservation of physiologically important nitric oxide functions require the use of isoform-selective inhibitors. Recently we reported reduced amide bond pseudodipeptide analogues as potent and selective neuronal nitric oxide synthase (nNOS) inhibitors (Hah, J.-M.; Roman, L. J.; Martasek, P.; Silverman, R. B. J. Med. Chem. 2001, 44, 2667−2670). To increase the lipophilicity a series of aromatic, reduced amide bond analogues (6−25) were designed and synthesized as potential selective nNOS inhibitors. The hypothesized large increase in isoform selectivity of nNOS over inducible NOS was not obtained in this series. However, the high potency with nNOS as well as high selectivity of nNOS over endothelial NOS was retained in some of these compounds (15, 17, 21), as well as good selectivity over inducible NOS. The most potent nNOS i...