cssi/SciSciGPT-SciSciNet huggingface dataset:
The single active X in human cells: evolutionary tinkering personified

All mammals compensate for sex differences in numbers of X chromosomes by transcribing only a single X chromosome in cells of both sexes; however, they differ from one another in the details of the compensatory mechanisms. These species variations result from chance mutations, species differences in the staging of developmental events, and interactions between events that occur concurrently. Such variations, which have only recently been appreciated, do not interfere with the strategy of establishing a single active X, but they influence how it is carried out. In an overview of X dosage compensation in human cells, I point out the evolutionary variations. I also argue that it is the single active X that is chosen, rather than inactive ones. Further, I suggest that the initial events in the process—those that precede silencing of future inactive X chromosomes—include randomly choosing the future active X, most likely by repressing its XIST locus.
Exploring the effects of congruence and Holland’s personality codes on job satisfaction: An application of hierarchical linear modeling techniques

Abstract This study applied hierarchical linear modeling to investigate the effect of congruence on intrinsic and extrinsic aspects of job satisfaction. Particular focus was given to differences in job satisfaction by gender and by Holland’s first-letter codes. The study sample included nationally represented 1462 female and 1280 male college graduates who held full-time jobs in 2000. Congruence was measured by using actual occupational and academic major codes. After controlling for the differences across three-letter Holland personality codes, results indicate that job satisfaction was largely a function of individual attributes rather than disparities in personality types. Holland’s congruence was most effective in explaining intrinsic dimensions of job satisfaction for females, and less effective for extrinsic job satisfaction for both genders. Social females and males were less satisfied with extrinsic satisfaction, while Conventional and Social females were more satisfied with intrinsic features in their vocational environments.
Studies on emergence, parasitization and control of the Pinyon Spindle Gall Midge, Pinyonia edulicola Gagné, in Colorado

A gall midge, Pinyonia edulicola Gagne (Diptera: Cecidomyiidae) causes serious damage to pinyon, Pinus edulis Engelm., in urban areas of Colorado. The gall midges infest developing needles, causing them to grow abnormally into spindle-shaped structures and to drop from the tree at the end of the first year, some five to seven years prematurely. Heavy infestations may result in substantial defoliation. Tests to determine efficacy of several insecticidal materials for control of P. edulicola were conducted in a residential area of Fort Collins during 1981 and 1982. Observations were also made on the population levels of the parasitoid Platygaster sp. (Hymenoptera: Platygasteridae). Sticky traps, plastic collection bags, and periodic observations were used to determine the onset of adult emergence to facilitate timing of application of treatments. The materials tested included acephate, carbofuran, oxydemetonmethyl, dimethoate, and two soap products reported to have insecticidal properties. Results indicate that effectiveness of treatments is dependent upon proper rate, timing, and method of application. None of the materials tested in 1981 reduced the number of midge infested needles. Carborufan, dimethoate and oxydemetonmethyl reduced infestation levels significantly in 1982 trials but differences among those treatments were not significant. Infestation levels on trees treated with acephate and insecticidal soap were not different from the check plots. About 1.7 percent of the midge population was parasitized by Platygaster sp. Zusammenfassung Untersuchungen uber Schlupfen, Parasitierung und Bekampfung der Nadelgallmucke Pinyonia edulicola Gagne an Pinus edulis in Colorado In den Siedlungen von Colorado verursacht die Gallmucke P. edulicola an Pinus edulis erhebliche Schaden, indem sie an den Nadeln spiralformige Verkrummungen und Gallen hervorruft, durch welche die Nadeln 5–7 Jahre zu fruh abfallen. Der Befall kann bis zum volligen Entnadeln gehen. Versuche uber die Wirksamkeit verschiedener Insektizide zur Bekampfung der Gallmucke wurden 1981 und 1982 in Fort Collins durchgefuhrt. Gleichzeitig erfolgten Beobachtungen uber den Parasitoiden Platygaster sp. Zur zeitlichen Festlegung der Bekampfungsaktion wurden Lichtfallen, Plastikbeuten und periodische Beobachtungen uber das Erscheinen der Gallmucke verwendet. Die getesteten Insektizide waren Acephate, Carbofuran, Oxydemetonmethyl, Dimethoate sowie 2 Seifenverbindungen. Die Ergebnisse zeigten, das die Wirksamkeit von der Dosierung, der Methode und dem Zeitpunkt abhing. 1981 konnten die Insektizide die Zahl der befallenen Nadeln nicht verringern. Dagegen reduzierten 1982 Corbofuran, Dimethoate und Oxydemetonmethyl den Befall signifikant. Die zwischen diesen Wirkstoffen bestehenden Unterschiede waren nicht gesichert. Dagegen zeigten die 2 Seifenverbindungen keine Wirkung. Etwa 1,7% der Gallmucken-Population wurde von der Schlupfwespe Platygaster sp. parasitiert.
The UCSD HIRES/Keck I Damped Lyα Abundance Database.* III. An Empirical Study of Photoionization in the Damped Lyα System toward GB 1759+7539

We investigate the ionization state of the damped Lyα system at z = 2.62 toward GB 1759+7539 through an analysis of ionic ratios sensitive to photoionization: Ar0/S+, Fe++/Fe+, N+/N0, and Al++/Al+. Approximately half of the metals arise in a mostly neutral velocity component with H I/H > 0.9, based on Fe++/Fe+ < 0.013. In contrast, the remaining half exhibit Fe++/Fe+ ≈ 0.3, indicative of a partially ionized medium with H I/H ≈ 0.5. These conclusions are supported by the observed N+/N0, Al++/Al+, and Ar0/Si+ ratios. We assess ionization corrections for the observed column densities through photoionization models derived from the CLOUDY software package. In the neutral gas, the ionization corrections are negligible, except for Ar0. However, for the partially ionized gas, element abundance ratios differ from the ionic ratios by 0.1-0.3 dex for (Si+, S+, Ni+, Al+)/Fe+ ratios and more for (N0, Ar0)/Fe+. Independent of the shape of the photoionizing spectrum and assumptions of the number of ionization phases, these ionization corrections have minimal impact (0.1 dex) on the total metallicity inferred for this damped Lyα system. Measurements of the relative elemental abundances of the partially ionized gas, however, have a greater than ≈0.15 dex uncertainty, which hides the effects of nucleosynthesis and differential dust depletion. We caution the reader that this damped system is unusual for a number of reasons (e.g., a very low Ar0/S+ ratio), and we believe its ionization properties are special but not unique. Nevertheless, it clearly shows the value of examining photoionization diagnostics such as Fe++/Fe+ in a larger sample of damped systems.
Onset of superfluidity in 4 He films adsorbed on disordered substrates

We have studied {sup 4}He films adsorbed in two porous glasses, aerogel and Vycor, using high-precision torsional oscillator and dc calorimetry techniques. Our investigation focused on the onset of superfluidity at low temperatures as the {sup 4}He coverage is increased. Torsional oscillator measurements of the {sup 4}He-aerogel system were used to determine the superfluid density of films with transition temperatures as low as 20 mK. Heat capacity measurements of the {sup 4}He-Vycor system probed the excitation spectrum of both nonsuperfluid and superfluid films for temperatures down to 10 mK. Both sets of measurements suggest that the critical coverage for the onset of superfluidity corresponds to a mobility edge in the chemical potential, so that the onset transition is the bosonic analog of a superconductor-insulator transition. The superfluid density measurements, however, are not in agreement with the scaling theory of an onset transition from a gapless, Bose glass phase to a superfluid. The heat capacity measurements show that the nonsuperfluid phase is better characterized as an insulator with a gap. {copyright} {ital 1997} {ital The American Physical Society}
Considering an organization's memory

The term organizational memory is due for an overhaul. Memory appears to be everywhere in organizations; yet, the term has been limited to a few uses. In this paper we examine what memory in an organization really is. Based on an ethnographic study of a telephone hotline group, this paper presents a micro-level analysis of a hotline call, the work activity surrounding the call, and the memory used in the work activity. We do this analysis from the viewpoint of distributed cognition theory, finding it fruitful for an understanding of an organization’s memory.
Parthenogenetic activation of porcine oocytes with guanosine-5'-O-(3'-thiotriphosphate).

A possible mechanism by which sperm activate oocytes may involve a G protein-mediated signal-transducing pathway. Artificial stimulation of G proteins leads to events very similar to those at fertilization in oocytes of several species. Here we report the effects of activation of a G protein with guanosine-5'-O-(3'-thiotriphosphate) (GTP-gamma-S), a hydrolysis-resistant analog of guanosine triphosphate (GTP), in porcine oocytes. Mature oocytes were injected with 1 mM GTP-gamma-S. In response to injection, oocytes underwent changes normally occurring at fertilization, i.e. cortical granule exocytosis, changes in the protein synthetic profile, pronuclear formation, and development to the blastocyst stage. Guanosine-5'-O-(2-thiodiphosphate) (GDP-beta-S; a metabolically stable analog of guanosine diphosphate [GDP] that inactivates the G protein) and the carrier medium (CM; medium in which the injected compounds were dissolved) were significantly less effective in oocyte activation. It is suggested that porcine oocytes contain the components of a G protein-mediated signaling pathway that might function in oocyte activation at fertilization.
Effect of disorder on the optical properties of colloidal crystals

Colloidal crystals offer a promising route for the formation of three-dimensional photonic crystals. The primary constraint in working with these materials is the disorder present in these self-assembled materials. Sphere vacancies, line dislocations, and random position errors all lead to a degradation in the optical properties. It is important to characterize these effects so as to guide further developments in colloidal crystal optics. Here, we report a systematic and quantitative study of disorder in colloidal crystals with visible diffractive properties. Using optical spectroscopy and digital imaging we have correlated several measures of structural disorder with variations in the transmissive and reflective optical properties. We observe a critical size distribution above which rapid deterioration of the lowest stop band is observed. Below this critical size distribution, we observe excellent optical quality, nearly independent of the size distribution. Single sphere vacancies also increase in crystals formed from more polydisperse spheres. The primary effect of this type of defect is to increase the broadband diffuse scattering.
Improving the diffraction of apoA-IV crystals through extreme dehydration.

Apolipoproteins are the protein component of high-density lipoproteins (HDL), which are necessary for mobilizing lipid-like molecules throughout the body. Apolipoproteins undergo self-association, especially at higher concentrations, making them difficult to crystallize. Here, the crystallization and diffraction of the core fragment of apolipoprotein A-IV (apoA-IV), consisting of residues 64–335, is presented. ApoA-IV64–335 crystallized readily in a variety of hexagonal (P6) morphologies with similar unit-cell parameters, all containing a long axis of nearly 550 A in length. Preliminary diffraction experiments with the different crystal morphologies all resulted in limited streaky diffraction to 3.5 A resolution. Crystal dehydration was applied to the different morphologies with variable success and was also used as a quality indicator of crystal-growth conditions. The results show that the morphologies that withstood the most extreme dehydration conditions showed the greatest improvement in diffraction. One morphology in particular was able to withstand dehydration in 60% PEG 3350 for over 12 h, which resulted in well defined intensities to 2.7 A resolution. These results suggest that the approach of integrating dehydration with variation in crystal-growth conditions might be a general technique to optimize diffraction.
Study of the smectic-A to hexatic-smectic-B transition in the binary system n-hexyl-4'-n-pentyloxybiphenyl-4-carboxylate and 4-propionylphenyl-trans(4-n-pentyl)cyclohexane carboxylate.

The polarizing microscope, differential scanning calorimeter, and high-resolution ac microcalorimeter were used to study the smectic-A to hexatic--smectic-B (SmA-Sm${B}_{H}$) transition in a binary-mixture system composed of n-hexyl-4'-n-pentyloxybiphenyl-4-carboxylate (65OBC) and 4-propionylphenyl-trans-(4-n-pentyl)cyclohexane carboxylate (PP5CC). The study strongly suggests that a virtual SmA-Sm${B}_{H}$ transition found in PP5CC will exhibit ideal critical behavior which may be different from the critical behavior observed in the extensively studied pure 65OBC system.
Columbia/HCA: villain or victim?

Bur ied in J.D. Kleinke ’s lengthy brief for Columbia/HCA are a number of points that are worth noting at the outset. First, the manner in which government procures goods and services from private, incomeseeking purveyors is always problematic, whether the purveyors are defense contractors, educational institutions, or the providers of health care. The retrospective, full-cost reimbursement by which Medicare has compensated the suppliers of home and skilled nursing care is particularly prone to problems. It subjects these purveyors to the same temptation that is faced by the millions of good citizens whose travel expenses are reimbursed retrospectively by their employers or clients and who forever make delicate judgments on what part of their many personal outlays on dinners, taxis, or telephone calls can legitimately be charged as travel expenses. To reduce that temptation, someone has to spell out in excruciating detail what is and is not to be reimbursed. Even after these rules have been written, there remains a large gray zone for errors and subtle judgments. Second, Kleinke may be right that the prolonged investigation of Columbia/HCA is intended as a shot across the bow of the entire health care industry. On the other hand, the information reportedly volunteered by scores of disillusioned former employees of Columbia/HCA, coupled with the spotlight the media had trained on this swashbuckling company for some time, probably would have made it difficult for the government to avoid a major and highly publicized investigation of Columbia/HCA. How could it have responded otherwise to the allegations made by the whistle-blowers and the media, especially when on the campaign stump both Republican and Democratic politicians regularly bewail the “fraud and abuse” in government programs and point to that “fraud and abuse” as a major potential source of financing promised tax cuts or still more government programs? Kleinke is properly cautious in withholding judgment on the accuracy of the accusations against Columbia/HCA. It is anybody’s guess what the investigation will unearth. But he would probably share my surprise if the actual dollar amount of fraud the government can prove in court would exceed even one-half of 1 percent of the company’s total billing to the government over the period in question. Unless whistle-blowers provide the government with irrefutable evidence of premeditated, massive, pervasive fraud, the bulk of the items at issue probably will be disposed of as random errors or as judgment calls on which reasonable people could disagree. Of course, in the end the company may try simply to buy out of the bad publicity of a prolonged, torturous trial by agreeing to pay a major fine, perhaps in the billions. All things considered, payment of a preemptive fine might be cost-effective from the share-
A Population-Based Study of Men With Low-Volume Low-Risk Prostate Cancer: Does African-American Race Predict for More Aggressive Disease?

Abstract Background Because of recent reports that suggested more pathologically aggressive disease in African-American (AA) men, we sought to compare pathologic features between AA and Caucasian-American men with low-risk, low-volume prostate cancer. Materials and Methods We analyzed the Surveillance, Epidemiology, and End Results database for pathologic differences based on race. Data on all men who were diagnosed between 2010 and 2011 with prostate cancer, T1cN0M0, Gleason score of 6 (3+3), prostate-specific antigen Results There were 1794 men who met the target study criteria. AA men were a median of 3 years younger (P Conclusion In the absence of definitive data to support a more aggressive natural history of very low risk prostate cancer in AA men, these data support continued use of active surveillance in this population.
Solvent-Free Matrix Dry-Coating for MALDI Imaging of Phospholipids

A fast and simple, solvent-free matrix deposition protocol was developed for positive ionization mode phospholipid analysis in tissues. Finely ground 2,5-dihydroxybenzoic acid was deposited onto sagittal mouse brain sections using a dry-coating technique, in which solid matrix particles were filtered directly onto the tissue through a 20-microm stainless steel sieve. Phospholipid signals were obtained directly off these sections, allowing acquisition of high-resolution MS images. These images were compared to those from serial sections that were spray-coated with a thin-layer chromatography (TLC) reagent sprayer. Signals obtained from the dry matrix deposition method were comparable to those from spray-coated sections, producing identical localization patterns with a simpler and faster sample preparation with virtually no analyte delocalization. This approach was found to yield highly reproducible results, eliminating much of the variance caused by operator differences, and making it an attractive alternative to the currently used matrix application methods.
The systematics of arbuscular mycorrhizal fungi in relation to current approaches to biological classification

During the past 30 years, numerous philosophical and procedural discussions have focused on the principles and methods of biological classification. From this have emerged three schools, phonetics, cladistics, and phyletics, each with its own theory of relationships, and its own set of explicit algorithms. At the same time, numerous studies on the economically important arbuscular mycorrhizal fungi have been completed. Some explicit approaches to classification have been made with higher fungi, and cladistic work has just begun on the vesicular arbuscular mycorrhizal (VAM) fungi. Thus it is now appropriate to examine the current status of the systematics of arbuscular mycorrhizal fungi and make suggestions for future work. The highest priority is to establish more refined circumscription of taxa at the lower levels of the hierarchy and to communicate these data and concepts to practicing physiologists, ecologists, etc., so that more rapid progress can be made in these areas. The limits of diversity of the group worldwide should be sought. A standardized identification manual (or atlas) would be most useful. Macromolecular studies are needed to help determine the close relatives of the VAM fungi as well as their interrelationships at the specific and generic levels. Continued emphasis needs to be placed on ontogenetic studies and their impact on variation in characters and states for taxonomic purposes. New quantitative classification approaches need to be used within the group, including phenetics and phyletics. Biogeographic concerns can then be addressed after the taxonomic issues have been more fully settled.
Water Immersion in Nephrotic Syndrome

Water immersion up to the neck has been described in detail in a series of papers by Epstein and his colleagues dealing with the response in the normal subject and in the cirrhotic patient.1–4 Epstein concluded that water immersion in 4 ft of water resulted in a physiological response similar to that produced by the rapid intravenous infusion of 2 liters of saline and that there was central venous distention with fluid compressed out of the lower limbs and abdomen into the central veins. These mechanisms have been discussed at length by Epstein and his colleagues in the normal and in the cirrhotic. However, an analogous situation, the response in the nephrotic patient, was ignored until we investigated the response to water immersion in 11 nephrotics.5–8
Patterns of forest structure, competition and regeneration in southwestern white pine (Pinus strobiformis) forests

Abstract Pinus strobiformis (southwestern white pine, abbr. PIST), a species that comprises a small but significant component of the mixed-conifer forests of the U.S. Southwest, faces an increasing threat from white pine blister rust (Cronartium ribicola, abbr. WPBR). This potentially lethal, non-native fungal pathogen is windborne and, therefore, virtually impossible to control. However, silvicultural strategies, such as thinning, reintroduction of natural fire regimes, and encouraging natural selection for rust-resistant genotypes, show promise for maintaining or restoring infected stands. To expand ecological knowledge of the species and guide management, we surveyed PIST in mixed-conifer stands throughout Arizona and portions of New Mexico. We examined PIST forest structure, regeneration, and competitive interactions. We found that PIST occupied lower canopy positions in Pinus ponderosa-dominated plots, thereby supporting its classification as an intermediate shade-tolerant species. Plots where PIST was a dominant component showed evidence of succession towards more tolerant conifers. PIST regeneration occurred relatively rarely and was negatively associated with increasing understory plant cover and open conditions. Although PIST faced heavy tree competition, with Pseudotsuga menziesii the most important competitor, small suppressed trees showed evidence of persistence.
When do cities specialize in production

Abstract When do cities specialize in production and when do they diversify? What determines the size and number of cities in an economy? These questions are addressed in a general equilibrium model of a closed economy consisting of a system of circular cities. The economy produces two final manufacturing goods with the use of labor and two groups of non-traded differentiated intermediate services. These two manufacturing goods are traded within the system at a positive transportation cost. The specialization of cities is due to the desire of the manufacturing industries to use a variety of product-specific differentiated intermediate services in production. This is because the larger the variety of services in the city the higher is the productivity of the manufacturing industries. Diversification is due to higher intercity transportation costs. The model presented generates two possible equilibrium configurations: (i) pure specialization, where each city in the economy specializes in the production of one group of differentiated services and one manufacturing good; and (ii) pure diversification, where all cities in the economy produce both groups of differentiated services and both manufacturing goods. The conditions under which each configuration emerges are identified. These conditions depend on the tradeoff between scale economy resulting from specialization and the saving in inter-city transportation costs in the case of diversification. Then some comparative static results, on stable equilibrium, are presented.
On reliability in finite element computations

Abstract Direct computation of engineering data from finite element solutions with reasonable guarantee of reliability is discussed with reference to practical engineering problem solving. The discussion focuses on a model problem for which experimental and numerical data are available.
Isolated human growth hormone deficiency. IV. The response of sexual ateliotic dwarfs to exogenous growth hormone

Abstract Sexual ateliotic dwarfs react acutely to human growth hormone treatment with a decrease in nitrogen and phosphorus excretion, a fall in serum urea nitrogen, and a rise in urinary calcium. The plasma insulin response to glucose is considerably augmented. A single subject, treated for one year, has exhibited an impressive increase in linear growth.
Reversal of diet-induced obesity and diabetes in C57BL/6J mice

We have previously shown that C57BL/6J (B6) mice develop severe obesity and diabetes if weaned onto high-fat diets, whereas A/J mice tend to be obesity and diabetes-resistant. The purpose of this study was to determine if obesity and diabetes in the B6 mouse could be completely reversed by reducing dietary fat content. After 4 months, both strains consumed more calories on a high-fat diet than on a low-fat diet, and both strains showed a higher feed efficiency (FE=weight gained/calories consumed) on the high-fat diet versus the low-fat diet. However, relative to A/J mice, B6 mice demonstrated a significantly higher FE on the high-fat diet. Hyperglycemia, hyperinsulinemia, and increased adiposity were apparent in B6 mice after 4 months on the high-fat diet regardless of whether the diet was begun at weaning or 4 months later. Correlational analyses showed that adiposity was strongly related to both insulin and glucose levels in B6 mice, but only moderately related to insulin levels in A/J mice. In obese B6 mice that were switched to a low-fat diet, obesity and diabetes were completely reversed. Adiposity, fasting glucose, and fasting insulin values in these mice were equivalent to those in B6 mice of the same age that had spent 8 months on the low-fat diet. In summary, our data show that in the B6 mouse the severity of diabetes is a direct function of obesity and diabetes is completely reversible by reducing dietary fat.
Introduction: Perspectives on Stress and Work

SUMMARY This essay places the issue of faculty stress within the larger context of workplace stress. We compare and contrast aspects of faculty stress with studies of stress in diverse nonacademic settings. We begin by reviewing the literature concerned with defining workplace stress. We then consider how concern for stress directs attention to the health implications of work. The literature in this area identifies factors that increase and inhibit feelings of stress among workers. The third section deals with the close connection between the concepts of stress and coping. We discuss studies of how workers experience stress and the social conditions associated with some workers' successful efforts to cope with stressful work. We conclude by briefly summarizing the studies that make up the rest of this volume.
Gas Transport and Response in Porous Silicon Sensors

Nanopore covered microporous silicon conductometric gas sensors have been produced via electrochemical etching and standard microfabrication techniques. Reversible and sensitive gas sensors working at room temperature have been fabricated. Sensing of NH3, NOx and PH3 at or below the ppm level have been achieved. The porous silicon (PS) surface has been modified using selective coatings including electroless tin, gold, nickel and copper solutions to increase the response to NOx, NH3, and PH3 respectively. The diffusion of the analyte species has been investigated in the nanopore and micropore regimes by numerical analysis. Comparing the response time of the hybrid porous sensor surface with numerical diffusion calculations on the pores, it has been observed that Knudsen diffusion time scales dominate the sensor response. A transduction model is proposed based on nanopore limited gas diffusion and the experimental response and recovery data.
Modeling the Transition from Adverse to Healthy Sleep Behaviors among School Age Children: A Simulation Approach

This research models and simulates, by way of a System Dynamics, approach sleep behavior in the presence of intervention strategies. The authors draw upon the established compartmental Susceptible, Infection, and Recovery (SIR) model used in epidemiology to characterize the potential for children and adolescents to both develop adverse sleep behaviors and to recover healthy sleep behaviors as they progress through educational levels. The development of healthy sleep during childhood and adolescence is important to the sustainment of healthy behaviors into early adulthood. Interventions designed to alter unhealthy sleep-related behaviors adopted at an early age may have a salubrious impact upon later chronic disease development. Our initial analyses adequately reproduce the drift experienced by children and adolescents who develop adverse sleep behaviors as they mature and transition through school levels. The ability to evaluate the effectiveness of interventions is important to public health officials. Investments in intervention programs shown to have positive health outcomes are attractive to policy makers. Although such programs may not be cost effective in the near-term, the programs may be cost saving in the long-term. The System Dynamics approach simulates behavior over time and allows policymakers insight into both the short-and longer-term cost and benefits.
A Direct Latent Variable Modeling Based Method for Point and Interval Estimation of Coefficient Alpha.

A direct approach to point and interval estimation of Cronbach’s coefficient alpha for multiple component measuring instruments is outlined. The procedure is based on a latent variable modeling application with widely circulated software. As a by-product, using sample data the method permits ascertaining whether the population discrepancy between alpha and the composite reliability coefficient may be practically negligible for a given empirical setting. The outlined approach is illustrated with numerical data.
Digital control of an unstable plant

An unstable third-order system is controlled digitally by pole-assignment technique and observer theory. The unstable plant is simulated on an EAI 680 analog computer, and a DEC-10 minicomputer is used to implement the controller. The minimum sampling rate required for stable operation is determined.
Perturbative results on QCD3 at finite temperature

Abstract Three-dimensional Yang-Mills theory is analyzed at finite temperature using perturbation theory. It is shown that all infrared divergences can be eliminated by introducing a self-consistent electric mass that is gauge invariant to all orders in perturbation theory. The dependence of the electric mass on temperature and coupling constant is non-analytic, and is shown to be calculable order by order in perturbation theory. Its behavior suggests the existence of a second-order phase transition by which the quark free energy becomes divergent, in agreement with Monte Carlo calculations. The magnetic mass and the lowest order correction to the spacelike string tension are computed. We argue that the Wilson string decouples at the critical point.
Dynamic holographic phase gratings in multiple-quantum-well asymmetric Fabry-Perot reflection modulators.

Dynamic holographic π-phase gratings can be written in a multiple-quantum-well asymmetric Fabry–Perot reflection modulator by spatial modulation of the quantum-confined exciton absorption. Operating near the Fabry–Perot resonance, the phase grating quenches the zero-order reflection and enhances the first-order diffraction efficiency. The diffraction efficiency of these structures as diffractive optics elements is not sensitive to the contrast ratio, which eases the constraints for device fabrication. Numerical simulations for multiple-quantum-well structures are presented that fully include refractive-index changes in response to a spatial modulation of the exciton absorption, which can be caused by any of several techniques, including free-carrier gratings, absorption bleaching, electro-optic effects, and photorefractive effects.
Development of the antioxidant defences in fetal life

At birth the newborn will encounter a much more O 2 -enriched world from the relatively hypoxic fetal state to the relatively hyperoxic newborn state. Investigators found late gestational chronology for the maturation of the protective pulmonary antioxidant enzymes (AOEs) in several species. These studies also confirmed the overlapping developmental patterns of the AOE and the surfactant system in fetal lung just prior to the time of birth. Nature has indeed provided a biochemical means to protect the lung of the full term newborn from the potentially cytotoxic effects of an O 2 -enriched world. Accumulating data indicate that the human fetal lung participates in this same biochemical ‘preparation for birth' phenomenon. Furthermore, full-term newborn rabbit lungs manifest increases in the activities of all AOEs when exposed to hyperoxia while the prematurely born pups fail to mount any increased AOE response to similar hyperoxic challenge. In the future, exogenous AOE treatment may be successful, for instance, by intratracheally instilled AOE using surfactant as a carrier. This method gives an homogeneous lung distribution and also improves lung uptake of superoxide dismutase (SOD) and catalase and protects newborn piglets from O 2 toxicity. Finally, molecular biology opens new avenues for therapy, for instance, by direct lung transfection of cDNAs encoding for the AOE.
The voice of youth: atmosphere in positive youth development program

Background: Positive youth development (PYD) programs adhere to the notion that all children have strengths and assets to be promoted and nurtured rather than deficits that require ‘fixing.’ The study of PYD programs indicates three aspects which set them apart from other programs for youth: activities, goals, and atmosphere. Of these, atmosphere has been least studied and what is known about atmosphere has been studied from a mostly adult perspective. Interestingly, while student voice is central to any educational process, students are not often consulted directly about their contributions.Aims: The purpose of this study was to examine the atmosphere of a PYD program grounded in self-determination theory (SDT) through the eyes of the participants. SDT suggests that people have the needs of relatedness, autonomy, and competence which must be met for successful growth.Method: An ethnographically informed case study was employed. Twenty-three participants from grades four and five (9 males and 14 females) ...
Regulation of Steroidogenesis in Cultured Porcine Theca Cells by Growth Factors

Growth factors [insulin-like growth factors (IGF-I, IGF-II), transforming growth factor-beta (TGF beta), epidermal growth factors (EGF)], found in the ovary and known to alter granulosal function, were assessed for their ability to modulate porcine thecal steroidogenesis. Theca cells from large porcine follicles (8-10 mm) were plated (5 x 10(5) cells/ml.well) in serum-free M199, treated with increasing doses of growth factors: IGF-1 (0.1-50 ng/ml), IGF-II (0.5-200 ng/ml), EGF (0.021-100 ng/ml), TGF beta (0.001-40 ng/ml), or insulin (0.01-50 micrograms/ml), with or without human CG [(hCG); 20 ng/ml], and incubated for 72 h. Levels of steroids in media were determined by RIA. Insulin increased (P less than 0.05) basal and gonadotropin-induced secretion of androstenedione, progesterone, estradiol, and testosterone. IGF-I increased (P less than 0.05) the basal and hCG-induced secretion of progesterone and androstenedione at the highest doses, but did not affect basal secretion of estradiol or testosterone. IGF-II, at the highest doses, increased (P less than 0.05) thecal steroidogenesis, but only after administration of hCG. In contrast, TGF beta increased (P less than 0.05) basal and gonadotrophin-induced secretion of estradiol but inhibited thecal secretion of progesterone, androstenedione, and testosterone. EGF did not alter thecal secretion of progesterone, androstenedione, or testosterone but significantly (P less than 0.05) inhibited basal and hCG-stimulated secretion of estradiol. In conclusion, insulin IGF-I, IGF-II, EGF, and TGF beta can modulate steroidogenesis in porcine theca cells.
Dynamics of topological defects in the Lβ′ phase of 1,2-dipalmitoylphosphatidycholine bilayers

Abstract We use the optical birefringence of 1,2-dipalmitoylphosphatidycholine bilayers (DPPC) in the gel (L β′ ) phase to study recombination dynamics of topological defects. The birefringence of anisotropic thin films, such as the L β′ phase of DPPC bilayers, is related to their molecular polarizability, different on the heads and the acyl chains. When the sample is cooled down into the L β′ phase, a period of rapid recombination (taking place over a few seconds) is followed by slow dynamics with metastable states existing in excess of several minutes. After this, either another metastable state or a truly stable state remains where no further change is observed, although a spatially non-uniform distribution of the orientation of the birefringence remains. We compare our results with a model for the free energy and the dynamics of the lipid bilayer in the gel state, finding good qualitative agreement.
Comments On Hsieh, Moriarty and Oosterhout

A response to the discussants, Nien-he Hsieh, Jeffrey Moriarty and J. (Hans) van Oosterhout, who took part in the March, 2005 symposium “The Political Theory of Organizations: A Retrospective Examination of Christopher McMahon’s Authority and Democracy: A General Theory of Government and Management” held in San Francisco as part of the Society for Business Ethics Group Meeting at the Pacific Division Meetings of the American Philosophical Association.
Evaluating Global Barriers to the Use of Red Palm Oil as an Intervention Food to Prevent Vitamin A Deficiency

Abstract: Vitamin A deficiency (VAD) is an important cause of blindness and premature death. Red palm oil (RPO) is the richest food source of VA-forming carotenoids. RPO carotenoid concentration and bioavailability were evaluated and this data used to estimate the amount of RPO needed to meet VA requirements. Amounts ranged from 6.7 to 29.2 g/d (1.5 to 6.5 tsp/d), which are easily consumed. The amount of RPO needed to supply recommended dietary intakes of VA for all 208100000 individuals most in danger for VAD worldwide for 1 y is 0.80 million metric tons, a fraction of annual world palm oil production. Despite its abundance, RPO has seldom been used for VAD prevention on a national level. Pareto charts were constructed to highlight the variables that influence the ability of RPO to prevent VAD on the national level. The most important variable by far was refining method. Most refining methods are designed to remove color and flavor from RPO, resulting in a bland product that lacks carotenoids. Thus, the important barriers to the use of RPO as a food-based intervention to prevent VAD appear to be that: (1) RPO requires refining, limiting its profitability and availability for small farmers. (2) The goal of most refining methods is to create a low-cost bland, odorless, and colorless fat which requires removal of carotenoids. (3) Cost, since RPO use competes with high-dose VA supplements, which are heavily subsidized. It appears that RPO could prevent VAD in many food-deficit countries if carotenoids were conserved during oil refining, and costs were low enough to make it an attractive alternative to nutritional supplements.
Competence and the overjustification effect.

The “overjustification effect” is manifested in decreased interest in an activity as a result of having been rewarded for participation in the activity. According to attribution theory's “discounting principle,” decreased interest occurs because the subject discounts the role of intrinsic motivation when a salient extrinsic reward is present. An alternative analysis based on the “competence principle” suggests that only rewards that convey no message of competence foster the overjustification effect, while manipulations that do convey competence information do not. A study crossing Reward (no reward-monetary reward) and Task Difficulty (hard-easy) supported the competence analysis. Subjects who succeeded on the hard task and thus felt competent manifested higher subsequent interest in the task. Consistent with the competence analysis, presence or absence of reward did not influence subsequent interest in the task.
One‐Center coulomb, two‐center hybrid, and two‐center coulomb integrals over STP functions

Diatomic integral formulas involving Slater-transform-Preuss functions are obtained for the Coulomb and hybrid types. One-center Coulomb integrals are also considered. All results have finite sums containing a one-dimensional numerical integration.
COMBINED EFFECTS OF CAFFEINE AND ALCOHOL DURING PREGNANCY ON BONES IN NEWBORN RATS

The combined effects of caffeine and alcohol on mineral contents of fetal mandibles and femurs were studied. Pregnant rats were divided into four groups: group 1, control; group 2, caffeine; group 3, alcohol; and group 4, caffeine-plusalcohol. Alcohol (1.0 g ethanol/kg body weight) was intubated twice daily, beginning at day 9 of gestation. Caffeine (2 mg/100 g body weight) was given as a dietary supplement. Groups 1 and 2 were intubated with isocaloric sucrose solution. At birth, randomly selected pups were killed and the mandible and femur were removed and dried. Ca, P, Mg, Zn and hydroxyproline in these bones were measured. Notwithstanding the dams' intake of caffeine and alcohol administered separately, the present results suggest that the combination of caffeine and alcohol exhibited the most detrimental effects.
Detecting bugs in register allocation

Although register allocation is critical for performance, the implementation of register allocation algorithms is difficult, due to the complexity of the algorithms and target machine architectures. It is particularly difficult to detect register allocation errors if the output code runs to completion, as bugs in the register allocator can cause the compiler to produce incorrect output code. The output code may even execute properly on some test data, but errors can remain. In this article, we propose novel data flow analyses to statically check that the value flow of the output code from the register allocator is the same as the value flow of its input code. The approach is accurate, fast, and can identify and report error locations and types. It is independent of the register allocator and uses only the input and output code of the register allocator. It can be used with different register allocators, including those that perform coalescing and rematerialization. The article describes our approach, called SARAC, and a tool that statically checks a register allocation and reports the errors and their types that it finds. The tool has an average compile-time overhead of only 8p and a modest average memory overhead of 85KB. Our techniques can be used by compiler developers during regression testing and as a command-line-enabled debugging pass for mysterious compiler behavior.
A Meta-Analytic Critique of Mael et al.’s (2005) Review of Single-Sex Schooling

Continued controversy in the United States over the relation of school gender composition to student outcomes is partially due to the failure to reach consensus on how to evaluate the research and the conclusions to be drawn from the research. In this review we examine major problems in the available research on single-sex schools, in terms of both theory and methodology. We critically examine the major review done by Mael et al. (2005) and identify serious problems in studies under review and the review methods. Drawing from both U.S. and non-U.S. samples, a subset of outcome measures (mathematical performance, verbal performance, self-esteem or self-concept) were analyzed using meta-analytic techniques. No significant effects for school gender composition were observed for either mathematical performance or self measures. There was a small advantage observed on verbal performance for students in single-sex schools, but in this comparison there was a strong relation between the direction of the effect on the outcome measure and pre-existing differences. For the three comparisons combined, preexisting student differences in SES or cognitive performance revealed advantages to students in single-sex schools. In conjunction with research showing that control of preexisting differences reduces or removes single-sex school advantages, this review provides support for the position that single-sex schools may offer no advantage to student cognitive performance or social development, but rather may reflect the consequences of a more select and advantaged student population.
An Evaluation of Sources of Nitrogen as Causes of Ground‐Water Contamination in Nassau County, Long Island

An evaluation of sources of nitrogen in an urban area indicates that it may be difficult to distinguish effects on the quality of underlying ground water. In Nassau County two principal sources of nitrogen are human waste water and fertilized turf. The effects of these sources, combined with other sources such as domestic animals and precipitation, are such that management of one source, i.e. the removal of waste water via sewers, may be less effective than expected.
Scrotal fistula from urethro-vasal reflux in paraplegia

A case is presented of a paraplegic in whom urethro-vasal reflux and scrotal fistula developed. Urodynamics testing showed a hyperreflexic bladder with detrusor-external sphincter dyssynergia.
Non-manifold level sets: a multivalued implicit surface representation with applications to self-collision processing

Level sets have been established as highly versatile implicit surface representations, with widespread use in graphics applications including modeling and dynamic simulation. Nevertheless, level sets are often presumed to be limited, compared to explicit meshes, in their ability to represent domains with thin topological features (e.g. narrow slits and gaps) or, even worse, material overlap. Geometries with such features may arise from modeling tools that tolerate occasional self-intersections, fracture modeling algorithms that create narrow or zero-width cuts by design, or as transient states in collision processing pipelines for deformable objects. Converting such models to level sets can alter their topology if thin features are not resolved by the grid size. We argue that this ostensible limitation is not an inherent defect of the implicit surface concept, but a collateral consequence of the standard Cartesian lattice used to store the level set values. We propose storing signed distance values on a regular hexahedral mesh which can have multiple collocated cubic elements and non-manifold bifurcation to accommodate non-trivial topology. We show how such non-manifold level sets can be systematically generated from convenient alternative geometric representations. Finally we demonstrate how this representation can facilitate fast and robust treatment of self-collision in simulations of volumetric elastic deformable bodies.