cssi/SciSciGPT-SciSciNet huggingface dataset:
Water in enzyme reactions: biophysical aspects of hydration-dehydration processes.

Water has been recognized as one of the major structuring factors in biological macromolecules. Indeed, water clusters influence many aspects of biological function, and the water-protein interaction has long been recognized as a major determinant of chain folding, conformational stability, internal dynamics, binding specificity and catalysis. I discuss here several themes arising from recent progress in understanding structural aspects of ‘direct’ and ‘indirect’ ligands in terms of enzyme-substrate interactions, and the role of water bridges in enzyme catalysis. The review also attempts to illuminate issues relating to efficiency, through solvent interactions associated with enzymic specificity, and versatility. Over the years, carbonic anhydrase (CA; carbonate hydro-lyase, EC 4.2.1.1) has played a significant role in the continuing delineation of principles underlying the role of water in enzyme reactions. As a result of its pronounced catalytic power and robust constitution CA was transformed into a veritable ‘laboratory’ in which active site mechanisms were rigorously tested and explored.
Design of airfoils and cascades of airfoils

This paper presents a method for generating blade shapes to be used as inputs to the direct- or inverse-bladedesign sequences. This method can generate subsonic or supersonic blades for compressors and turbines, or isolated airfoils, but the discussion in this paper is limited to subsonic-exit turbine blade rows. Gas-turbine blades are usually designed by a mixture of iterative, direct- and inverse-blade-design methods. The iterations are enormously reduced if the initial blade shape has performance characteristics near the desirable ones. The desirable performance characteristics are presented, and ways to manipulate the input striving for such characteristics (minimizing design iterations) are discussed. The overspeed regions near the leading edge are avoided. The performance curves of three blades generated by this method are included. It is concluded that blade performance is extremely sensitive to small changes in the shape of the surfaces and to changes or discontinuities in the derivative of the curvature of the blade surfaces. The order of magnitude of these changes is the same or lower than the order of magnitude of the thickness distribution of the boundary layers.
Gelastic seizures of neocortical origin confirmed by resective surgery.

Ictal laughter is a relatively unusual phenomenon that appears to arise from within hypothalamic hamartomas. Gelastic seizures of neocortical origin are rare and when reported typically originate from temporofrontal regions in proximity to the hypothalamus, raising the possibility of a subtle lesion in the hypothalamus. A girl with gelastic seizures originating in a dysembryoblastic neuroepithelial tumor at the cranial vertex had resolution of her seizures following surgical resection. Electrical propagation of seizures via the cingulate gyrus appears to be an alternative mechanism underlying gelastic seizures. (J Child Neurol 2000; 15:835-838).
Aqueous geochemistry and diagenesis in the eastern Snake River Plain aquifer system, Idaho

Water budget and isotopic analyses of water in the eastern Snake River Plain aquifer system confirm that most, if not all, of the water is local meteoric in origin. Solute mass-balance arguments suggest that ∼5 × 10 9 moles of calcite and 2.6 × 10 9 moles of silica are precipitated annually in the aquifer. Isotopic evaluations of calcite and petrographic observation of silica support the low-temperature origin of these deposits. Approximately 2.8 × 10 9 moles of chloride, 4.5 × 10 9 moles of sodium, 1.4 × 10 9 moles of sulfate, and 2 × 10 9 moles of magnesium are removed annually from the aquifer framework by solution. Proposed weathering reactions are shown to be consistent with mass balance, carbon isotopes, observed mineralogy, and chemical thermodynamics. Large quantities of sodium, chloride, and sulfate are being removed from the system relative to their abundances in the rock. Sedimentary interbeds, which are estimated to compose 2 )/yr or less than half the average of the North American continent. This contrasts with the rate for the eastern Snake River basin, 34 (Mg/km 2 )/yr, which is almost identical to the average for the North American continent. Identification and quantification of reactions controlling solute concentrations in ground water in the eastern plain indicate that the aquifer is not an “inert bathtub” that simply stores and transmits water and solutes but is undergoing active diagenesis and is both a source and sink for solutes.
A review of the US Grade A raw milk supply, its quality, marketing and pricing

As with any business, profitability is essential for the successful operation of a dairy farm. Profitability depends on the production performance of the dairy herd and a favourable price for the milk produced. While the Grade A regulations set the minimum quality standards and provide for monitoring and enforcement, the federal order system insures the producer a fair market price. Through the integration of performance standards and marketing, the United States has benefited from an abundant supply of safe and wholesome milk. However, the marketing and pricing of the US raw milk supply is beginning to model itself after the UK Milk Board concept because of mergers of cooperatives 1-3 into ever larger units, increase in size of production units at the farm level and regulation of the surplus Grade A raw milk supply.
The use of floating overhead cover by warmwater stream fishes

Increasing the amount of woody debris in streams has often increased population size of one or more focal species whereas clearing a stream of woody debris has often reduced populations. Alterations of the amount of woody debris change multiple aspects of the habitat simultaneously, so it is very difficult to know what particular stimulus or combination of stimuli evoked the changes in the fish populations. The purpose of this research was to alter habitat by the addition of overhead cover alone, and to see whether or not that single change would affect the distribution of stream-dwelling fishes. The addition of solid, floating cover objects 1.8 m by 2.4 m resulted in increased local populations of bluntnose minnow (Pimphales notatus), creek chub (Semotilus atromaculatus), and longear sunfish (Lepomis megalotis) five to six weeks later, but did not change the distribution of four other species: white sucker (Catostomus commersoni), green sunfish (Lepomis cyanellus), bluegill (Lepomis macrochirus), and largemouth bass (Micropterus salmoides). These results showed that for some species at least, changes in channel morphology, visual isolation, and amelioration of flow produced by adding three-dimensional complex woody debris were not essential for making locally attractive habitat changes in a warmwater stream. The effectiveness of overhead cover as used here would be expected to vary for different species and depend on such things as predation threat, flow, and food levels.
Association of oxytocin receptor (OXTR) gene variants with multiple phenotype domains of autism spectrum disorder

Autism spectrum disorder (ASD) is characterized by core deficits in social behavior, communication, and behavioral flexibility. Several lines of evidence indicate that oxytocin, signaling through its receptor (OXTR), is important in a wide range of social behaviors. In attempts to determine whether genetic variations in the oxytocin signaling system contribute to ASD susceptibility, seven recent reports indicated association of common genetic polymorphisms in the OXTR gene with ASD. Each involved relatively small sample sizes (57 to 436 families) and, where it was examined, failed to identify association of OXTR polymorphisms with measures of social behavior in individuals with ASD. We report genetic association analysis of 25 markers spanning the OXTR locus in 1,238 pedigrees including 2,333 individuals with ASD. Association of three markers previously implicated in ASD susceptibility, rs2268493 (P = 0.043), rs1042778 (P = 0.037), and rs7632287 (P = 0.016), was observed. Further, these genetic markers were associated with multiple core ASD phenotypes, including social domain dysfunction, measured by standardized instruments used to diagnose and describe ASD. The data suggest association of OXTR genetic polymorphisms with ASD, although the results should be interpreted with caution because none of the significant associations would survive appropriate correction for multiple comparisons. However, the current findings of association in a large independent cohort are consistent with previous results, and the biological plausibility of participation of the oxytocin signaling system in modulating social disruptions characteristic of ASD, suggest that functional polymorphisms of OXTR may contribute to ASD risk in a subset of families.
Energy disposal in the laser photodissociation of ICN and BrCN at 300 K and in a free jet expansion

Abstract Photodissociation of ICN and BrCN via the long-wavelength portions of their A continua leads to CN(X 2 Σ + ) rovibrational excitation which can characterize the excited potential surfaces. Parent rovibrational excitation strongly influences the observed CN state distributions.
Boundedly rational rule learning in a guessing game

Abstract We combine Nagel's “step- k ” model of boundedly rational players with a “law of effect” learning model. Players begin with a disposition to use one of the step- k rules of behavior, and over time the players learn how the available rules perform and switch to better performing rules. We offer an econometric specification of this dynamic process and fit it to Nagel's experimental data. We find that the rule of learning model vastly outperforms other nested and nonnested learning models. We find strong evidence for diverse dispositions and reject the Bayesian rule-learning model. Journal of Economic Literature Classification Numbers: C70, C52, D83.
Application of team‐based 360° feedback systems

An increasingly important performance measurement tool, especially in the area of teams, is 360° feedback. This paper discusses the theories behind the system, and provides an in‐depth review of the techniques of implementing 360° feedback in an organization. Steps for implementation include selection of raters, questionnaire construction, feedback, presentation, and follow‐up. Additional considerations such as rater responsibility, cost, organizational change and support, benefits, and dangers of abuse or mis‐usage of the system are addressed. Special considerations are discussed for using the system in team settings and how the system can be built‐in to a developing team system or adapted for use in an existing one. More research is currently needed in areas such as quality of samples, process information, training effectiveness, and sustaining the process.
Electrical conduction in glassy carbon

Abstract The electrical conductivity and Hall effect of a disordered carbon have been investigated in the temperature range 10–300 K and magnetic fields up to 50 KG. The structure of the material was changed by heat treating in the temparature range 1000–2800°C. For heat treatment temperatures (HTT) greater than 2000°C the conductivity was found to be the sum of a temperature-independent contribution due to diffuse boundary scattering and a hopping contribution following a T − 1 4 law. For HTT less than 2000°C, at the lowest measurement temperatures the conductivity exhibits a logarithmic temperature dependence characteristic of Kondo systems. An energy band structure for these disordered carbons is proposed in which the Fermi level is pinned by localized states.
A distributed data component for the Open Modeling Interface

As the volume of collected data continues to increase in the environmental sciences, so too does the need for effective means for accessing those data. We have developed an Open Modeling Interface (OpenMI) data component that retrieves input data for model components from environmental information systems and delivers output data to those systems. The adoption of standards for both model component input–output interfaces and web services make it possible for the component to be reconfigured for use with different linked models and various online systems. The data component employs three techniques tailored to the unique design of the OpenMI that enable efficient operation: caching, prefetching, and buffering, making it capable of scaling to large numbers of simultaneous simulations executing on a computational grid. We present the design of the component, an evaluation of its performance, and a case study demonstrating how it can be incorporated into modeling studies.
Shell-model study of the N = 49 isotones

Abstract The N = 49 isotones 88Y, 89Zr, 90Nb, 91Mo, 92Tc and 93Ru are studied in the framework of the shell model with valence nucleons occupying the 2 p 1 2 and 1 g 9 2 single-particle levels. The residual proton-neutron effective interaction is determined by a least-squares fit to the experimental energies of states in these nuclei with well established spins and parities. We examine the effects of requiring the effective interaction to conserve seniority and model-space isospin. It is found that the existing body of experimental data is consistent with conservation of T = 1 seniority but that the data call for small isospin mixing that can be traced to modelspace truncation effects. The resulting shell-model wave functions are used to calculate energy levels, single-nucleon spectroscopic factors and electromagnetic transition rates. These model wave functions also provide a basis for a qualitative discussion of the weak coupling multiplet structure that persists in the low-lying states of all of these nuclei. In general, all observed properties of yrast levels and analog states are well reproduced by our model as are the positions of many non-yrast levels. Within this model space unique 0+ anti-analog states emerge in 88Y, 90Nb and 92Tc, but the 9 2 + and 1 2 − anti-analogs are highly fragmented in the even-Z nuclei.
Positronium negative ion: Molecule or atom?

A highly accurate calculation is supplemented by an adiabatic approximation to explore the resonance spectrum of positronium ${\mathrm{Ps}}^{\mathrm{\ensuremath{-}}}$. Surprisingly, the spectrum can be understood and classified with ${\mathrm{H}}_{2}^{+}$ quantum numbers by treating the interelectronic axis of ${\mathrm{Ps}}^{\mathrm{\ensuremath{-}}}$ as an adiabatic parameter. We report and interpret the existence of $^{1}$S shape resonances, a phenomenon so far unknown in three-body Coulomb systems. The new results on ${\mathrm{Ps}}^{\mathrm{\ensuremath{-}}}$ combined with previous results for ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$ suggest the existence of a resonance spectrum and its similarity for all ABA Coulomb systems with charges \ensuremath{\Vert}${\mathit{Z}}_{\mathit{A}}$/${\mathit{Z}}_{\mathit{B}}$\ensuremath{\Vert}=1 and masses ${\mathit{m}}_{\mathit{A}}$/${\mathit{m}}_{\mathit{B}}$\ensuremath{\ge}1.
Genetic dissection of pancreatic trypsin inhibitor.

Abstract In a previous study, a genetic screening procedure was used to identify variants of bovine pancreatic trypsin inhibitor that can fold to an active conformation but that are inactivated much more rapidly than the wild-type protein in the presence of dithiothreitol (DTT). The mechanisms by which 30 of these DTT-sensitive variants are inactivated have now been investigated. Some of the amino acid replacements cause rapid inactivation in the presence of DTT because the three disulfides of the native protein are reduced up to 300-fold faster than for the wild-type protein, leading to complete unfolding. Other substitutions, however, do not greatly increase the rate of complete reduction and unfolding but lead to accumulation of an inactive two-disulfide species. There is a striking correlation between the locations of the DTT-sensitive amino acid replacements in the three-dimensional structure of the protein and the mechanisms by which the variants are inactivated. All of the substitutions that cause rapid unfolding are clustered at one end of the folded protein, in the vicinity of the two disulfides that are reduced most slowly during unfolding of the wild-type protein, while substitutions of the other class are all located at the other end of the protein, near the trypsin binding site. These results indicate that the kinetic stability of native bovine pancreatic trypsin inhibitor and its ability to function as a protease inhibitor are largely influenced by residues in two distinguishable regions of the folded protein.
Inhibition by glucocorticoids of endocytosis in a macrophage-like cell line.

A macrophage-like cell line (P388D1) has been used to demonstrate that glucocorticoids inhibit the fluid-phase endocytosis of fluorescein-labeled dextran (FITC-dextran). Initial experiments demonstrated that the interaction of FITC-dextran with cells had all the features of fluid-phase uptake, ie, the amount taken up was proportional to the concentration in the medium, the uptake proceeded continuously with time and was blocked at 4°C. Dexamethasone (10−7M) had no effect on endocytosis until 11 hours after addition of the steroid, when it inhibited the uptake of FITC-dextran by 35%. The amount of inhibition increased with longer exposure times to the hormone up to 50% after 22 hours. Although this effect on endocytosis was Observed prior to any effect on growth of the cells, endocytosis as well as cell proliferation were inhibited in a dose-dependent fashion. A preliminary survey of selected steroids has established that the inhibition of endocytosis was restricted to steroids of the glucocorticoid class. The key experiments were also performed using horseradish peroxidase instead of FITC-dextran with, essentially, identical results.
Blood pressure and heart rate effects of kynuramine in pithed rats.

Abstract Kynuramine increased heart rate and blood pressure in pithed rats. Heart rate responses were blocked by β-adrenoceptor antagonists and reserpine pretreatment. Both of these treatments reduced the pressor responses to kynuramine. Remaining pressor activity was inhibited by phentolamine. The pressor responses to kynuramine were reversed to depressor responses during infusion of norepinephrine but not vasopressin. It is concluded that kynuramine releases cardiac catecholamines and acts as a partial agonist on vascular α-adrenoceptors.
Alumina Particle Velocity and Temperature in a Solid Rocket Plume

A S part of a study of the smoke characteristics of -fmsolid propellant rockets, a mathematical model has been developed for prediction of the velocity and temperature of alumina particles on the axis of the plume. The model assumes that the particles are spherical, and sufficiently diluted in the plume so that there is no flow interference with the main gas stream nor interaction among the particles. Momentum and thermal effects of shocks in the plume, and radiation were not included in the analysis. The calculated results for 5, 10, and 20^ radius particles in the exhaust from an ammonium perchlorate-rubber composite propellant are presented in Figs. 1 and 2. Previous papers by Kliegel, Hoglund, and Carlson and Hoglund were concerned with particle velocity and temperatures in the rocket nozzle. The present paper is an extension of this work into the external plume itself. Since the gas density in a rocket exhaust is very low compared with the density of an alumina particle, the only forces on the particle that need to be considered are body and surface drag FD, transient flowfield response—the Basset history term FH, and external potential fields Fe, e.g., gravity. The forces due to the flow pressure gradient and the so-called "added-mass' are negligible.
Current and future challenges of antithrombotic agents and anticoagulants: strategies for reversal of hemorrhagic complications

Recent years have seen the introduction of a number of new anticoagulant agents, each offering a unique profile of benefits and potential drawbacks. Anticoagulants are now available or in development that target platelet recruitment, aggregation, and adhesion, in addition to a growing number of direct or indirect thrombin inhibitors. However, the potential for anticoagulant-induced hemorrhage and the need for effective antidotes that can reverse this adverse effect remain major considerations when prescribing any anticoagulant therapy. The expanding range of anticoagulants brings with it a renewed challenge of identifying suitable treatments to reverse anticoagulant-induced hemorrhage. This paper reviews different mechanisms of anticoagulant action and the theoretical role of recombinant factor VIIa (rFVIIa) and other agents currently in development to reverse bleeding complications associated with both traditional and novel anticoagulant therapies.
Parent Beliefs about Treatment Credibility and Effectiveness: Assessment and Relation to Subsequent Treatment Participation.

We assessed parents’ beliefs about treatment credibility and effectiveness and examined the influence of these beliefs on subsequent treatment participation. Seventy-six parents completed the Credibility/Expectancies Questionnaire—Parent Version (CEQ-P), and subsequently participated in treatment for their child's clinically referred conduct problems. The key findings were that: (a) the CEQ-P is composed of two components that measure parents’ treatment credibility and expectancies; (b) the total scale and each component are internally consistent and have strong test-retest reliability; (c) scores on the CEQ-P are significantly associated with scores on a measure of parent motivation for treatment, supporting the construct validity of this measure; and (d) scores on the CEQ-P at the first clinic visit significantly predict subsequent adherence to treatment procedures above and beyond demographic variables and parent motivation for treatment. This study provides an efficient and psychometrically sound measure of parent beliefs about treatment and demonstrates the importance of such beliefs for subsequent treatment adherence.
All pain, no gain? Why adopting sales force automation tools is insufficient for performance improvement

Abstract The dawning of the 21 st century brought a wave of research into the phenomenon of sales force automation (SFA)—technology tools aimed at enabling sales organizations to better practice customer relationship management. While the academic literature has offered great insight into how an organization can increase the likelihood that its sales force will adopt a new technology system, a great majority of research stops there. This is unfortunate in that companies mistakenly infer that use of an SFA system is the major hurdle and that simply motivating SFA use will be the key to unlocking improved performance. However, this is often not the case; many organizations are able to get their sales force to use an SFA system but do not see improvements in performance. As such, after briefly providing an overview of the factors affecting SFA use, this research provides insight into why use alone may not contribute to long-term improvements in a firm's sales performance. Key empirical findings and theoretical arguments from the extant literature are considered and a list of best practices is offered here to help managers bridge the gap between SFA use and improved sales effectiveness and efficiency.
Photooxidations catalyzed by plant and bacterial extracts and by riboflavin-5'-phosphate.

Abstract 1. 1. The photo-oxidation of the 2,6-dichlorophenolindophenol-ascorbate couple by sugar beet leaf homogenate is stimulated by the addition of FMN, indigo carmine or 1,2-napthoquinone4-sulfonic acid. The stimulation is probably due to interaction of these compounds with the photo-chemical [H] system. 2. 2. The 2,6-dichlorophenolindophenol-ascorbate couple was photo-oxidized at least 17 times as fast as exactly reduced 2,6-dichlorophenolindophenol by sugar beet homogenate or sonic extracts of R. rubrum and Rsp. spheroides . 3. 3. Reduced 2,6-dichlorophenolindophenol was photo-oxidized by chlorophyll a in ethanolic solutions, but the rate fell off rapidly as the water content increased in the system. 4. 4. Reduced 2,6-dichlorophenolindophenol and reduced cytochrome c were photo-oxidized rapidly by FMN in aqueous media. The photo-oxidation of reduced 2,6-dichlorophenolindophenol was further stimulated by added catalase or peroxidase. These reagents did not affect cytochrome c photo-oxidation. 5. 5. These data are discussed in relation to two proposed mechanisms for oxidation of the 2,6-dichlorophenolindophenol-ascorbate couple by chloroplasts.
An electrophysiological study of the effects of d-tubocurarine, atropine, and α-bungarotoxin on the cholinergic receptor in innervated and chronically denervated mammalian skeletal muscles

Abstract An electrophysiological study of the action of d -tubocurarine ( d -TC), atropine, and α-bungarotoxin (BuTX) was made on the innervated and chronically denervated diaphragm and soleus muscles of the rat and mouse. All three drugs were able to block endplate potentials of innervated muscles as well as acetylcholine (ACh) sensitivity of chronically denervated muscles. The effects of atropine and d -TC were fully reversed upon washing with Ringer's solution, white the effects of BuTX were only partially reversed. The reversibility of BuTX was more evident at extrajunctional areas in chronically denervated muscles than at the innervated endplate region, but in both cases only a fraction of the normal response could be detected after intensive washing for at least 2 hr. The blockade of ACh sensitivity in chronically denervated muscles required a concentration of d -TC 10-fold higher than that necessary to block the endplate potentials of innervated muscles. BuTX and d -TC did not affect the ionic permeabilities of the muscle fiber during an action potential while atropine decreased both Na + and K + conductances, the magnitude of the effect being dependent on the frequency of stimulation. At the endplate region, d -TC was much more effective than atropine in protecting against the irreversible effect of BuTX. In the chronically denervated preparation, however, neither of the two drugs effectively protected against BuTX. It is concluded that in terms of their reactivities to cholinolytic agents, the extrajunctional receptors induced by chronic denervation of skeletal muscles are qualitatively similar to those found at endplate regions of normal muscles, but that they exhibit differences in their quantitative interaction with different cholinolytic agents. The data further indicate that atropine interacts with the ionic conductance modulator unit associated with the cholinergic receptor, rather than with the ACh receptor itself.
Delayed rehearsal of pictures

In each of five experiments, instructions to rehearse previously presented pictures increased the likelihood of their being identified in a later test. The pictures were simple line drawings of common objects, and the cues were the names of the objects. The test entailed discriminating each target picture from among four distractor pictures, which depicted objects bearing the same name. In Experiments 1–3, subjects viewed sequences of three, four, and eight pictures, respectively. Following each sequence, a poststimulus cuing procedure was used to direct the subjects to rehearse some subset of the pictures. In each of these experiments, recognition was higher for the cued than for the uncued pictures. Experiments 4 and 5 showed that the effect of cuing diminished as the lag between picture presentation and cuing increased.
The metabolism of testosterone by the periwinkle (Littorina littorea) in vitro and in vivo: Effects of tributyl tin

Abstract Exposure to tributyl tin (TBT) at concentrations as low as 0.5 ng/liter has been associated with disrupted sexual physiology (imposex) in 40–50 species of marine gastropod. Imposex is a state of pseudohemaphrodism in which females exhibit nonfunctional secondary male characteristics. It has been suggested that the mechanism underlying imposex involves disrupted metabolism of endogenous sex hormones and in particular inhibition of cytochrome P450-dependent aromatization of androgens to estrogens. In the current study, the effects of TBT on the ability of the Periwinkle ( Littorina littorea ) to metabolize the androgenic sex steroid testosterone was examined in vitro and in vivo . Microsomes were prepared from ‘digestive gland’ (visceral complex including the gonads) and combined kidney and gill fractions. CO-ligated reduced difference spectra contained peaks at 459 nm and calculated P450 contents of 0.3 and 0.05 nmol/mg. Digestive gland microsomes were found to be capable of oxidative metabolism of testosterone in either the presence or absence of NADPH. In the absence of NADPH, testosterone was metabolized to androstenedione, 6β-, 6α- and 15β-hydroxytestosterone, 17β-estradiol and an unidentified metabolite possibly 3α-androstene-17β-diol. In the presence of NADPH the same products were produced at a higher rate but the major products formed were the products of the NADPH-dependent steroid 5α-reductase-3α(β)hydroxysteroid dehydrogenase pathway; dihydrotestosterone (DHT) and 3α(β)androstane-17β-diols (DHT diols). TBT, even at high concentrations up to 100 μM, had only modest effect on P450-dependent testosterone metabolism in vitro , producing increases in androstenedione formation and only 30–40% inhibition of aromatase. In vivo , [ 14 C] testosterone was injected directly into the cephalopedal sinus of adult snails and animals maintained in sea water at 15 °C for 42 h in the presence of 0, 0.5 and 5 mM TBT. Testosterone was almost completely metabolized during this time, predominantly to water-soluble sulfur conjugates of testosterone, the 5α-reduced products and 6α-hydroxytestosterone. However, with increasing concentrations of TBT, more radioactivity was retained within the animal and was increasingly associated with organic extractable unmetabolized testosterone and its phase I products androstenedione, dihydroandrostenedione (DHA), DHT and DHT-diols. Thus it appears that, in vivo , TBT inhibits sulfur conjugation of testosterone and its phase I metabolites and their excretion resulting in a build-up of pharmacologically active androgens in the tissues. This data are consistent with the hypothesis that TBT-induced imposex in sensitive gastropods, such as stenoglossans, may arise from peturbations in sex steroid metabolism. However, the major biochemical targets of TBT appear to be steroid conjugation and excretory transport mechanisms rather than P450-dependent oxidative pathways such as aromatase.
On the origin and meaning of bibliometric indicators : journals in the social sciences, 1886-1985

In this study, it is demonstrated that, as disciplines mature, research articles in core journals become increasingly similar in their bibliometric features. Data were collected from research articles published in core journals in sociology, political science, and economics from 1886 through 1985 (N=8,634). Variation in levels of use of footnotes and of visuals within the same discipline was found to decline over time, even though the means about which the variation was measured changed throughout the period. It is suggested that authors, editors, referees, and others come to view prevailing practices in the use of footnotes and visuals as disciplinary standards for the presentation of research. Comparison of change in levels of variation to change in level of consensus described in disciplinary histories suggested an association between levels of agreement on presentational standards and levels of cognitive consensus
Observing interactions of abusive and nonabusive dyads: information extracted by accurate and inaccurate judges

This study describes the reported observations of protective services workers who varied in the accuracy with which they could discriminate abusive from nonabusive mother-child interactions. Participants viewed videotapes of two abusive and two nonabusive dyads. They noted behaviors that suggested an abusive history and behaviors that suggested a nonabusive history for each dyad. Comparisons of more and less accurate judges indicated that accurate judges observed more evidence for abuse when the dyad actually was abusive. The informational advantage of experts was not limited to detecting interactional difficulties in abusive dyads; they also reported observations of more favorable behaviors of nonabusive dyads. Highly accurate judges were more likely to observe communication patterns, task-oriented behavior, and other-directed behaviors than were less accurate judges. These findings suggest that specific information-processing factors may vary with clinical expertise. Language: en
Perturbation and Resilience: A Long-Term, Whole-Lake Study of Predator Extinction and Reintroduction

This paper presents the results of a long-term study of changing predator densities and cascading effects in a Michigan lake in which the top carnivore, the largemouth bass (Micropterus salmoides), was eliminated in 1978 and then reintroduced in 1986. The elimination of the bass was followed by a dramatic increase in the density of planktivorous fish, the disappearance of large zooplankton (e.g., two species of Daphnia that had his- torically dominated the zooplankton community), and the appearance of a suite of small- bodied cladoceran (zooplankton) species. The system remained in this state until bass were reintroduced. As the bass population increased, the system showed a steady and predictable return to its previous state; planktivore numbers declined by two orders of magnitude, large- bodied Daphnia reappeared and again dominated the zooplankton, and the suite of small- bodied cladocerans disappeared. Within each cladoceran species there was a steady increase in mean adult body size as planktivore numbers declined. Total zooplankton biomass in- creased - 10-fold following the return of large-bodied Daphnia, and water clarity increased significantly with increases in Daphnia biomass and total cladoceran biomass. These changes in community structure and trophic-level biomasses demonstrate the strong impact of removing a single, keystone species, and the capacity of the community to return to its previous state after the species is reintroduced.
Selection criteria for sealing glasses for SiC packaging

Three very different commercial glasses were chosen for their close matched coefficient of thermal expansion with SiC and were tested in view of their application as glass sealants for SiC packages. The occurrence of bubbles at the glass/SiC interface was attributed to the reaction between the SiC substrate and certain oxides present in the glasses forming CO gas. Selection criteria were developed based on thermodynamic calculations in order to determine which glass composition would be stable with SiC. This approach provides valuable information in tailoring suitable glasses for the demanding applications that SiC materials may encounter in packaging for high temperature applications.
A new human pancreatic carcinoma cell line developed for adoptive immunotherapy studies with lymphokine-activated killer cells in nude mice.

A human tumor cell line designated SU.86 has been established from a moderate-to-poorly differentiated pancreatic carcinoma of ductal origin specifically for adoptive immunotherapy studies. This line was characterized as to its ability to be lysed in vitro by autologous and allogeneic lymphokine-activated killer (LAK) and natural killer cells and to grow in nude mice. SU.86 has been growing continuously in cell culture for more than 100 passages since 22 September 1986. Transplantation orthotopically and heterotopically into athymic Swiss nude mice showed that tumor take was 100% in the orthotopic position when young (4 to 6 wk old) mice were used and 0% when adult (8 wk old) mice were used (P=0.004). In the heterotopic position (subcutaneous), tumor take was 100% in neonate (2 to 3 wk old) and young mice and 50% in adults. The rate of tumor growth was inversely correlated with age (P<0.001). The histologic pattern is similar to that observed in most human pancreatic carcinomas with pseudoglandular structures and frequent mitotic figures. SU.86 has a doubling time of 77 h in vitro and produces carcinoembryonic antigen, 594 ng/106 cells in 3 d. Chromosomal analysis shows heterogeneity with two notable cell subpopulations. The cell line is moderately sensitive to lysis by LAK cells in a standard, 4-h chromium-51 release assay (35.4±4.0%). When grown together with LAK cells in vitro, it is lysed completely in culture in 8 to 15 d, depending on the serum concentration.
On theorems of Berlowitz and Berndt

Abstract Let F(s) = π −s 2 Γ( s 2 )ζ(s) . Using the fact that ReF(s) = 0 whenever arg F(s) ≡ π 2 ( mod π) it will be shown from the asymptotic behavior of Γ(a + it) as |t| → ∞ that for σ > 1 2 the number of zeros of Re F(σ + it) on 0 ≤ t ≤ T is at least T 2π log( T 2π ) + O(T) .
Detection, classification, and tracking of targets

Networks of small, densely distributed wireless sensor nodes are being envisioned and developed for a variety of applications involving monitoring and the physical world in a tetherless fashion. Typically, each individual node can sense in multiple modalities but has limited communication and computation capabilities. Many challenges must be overcome before the concept of sensor networks In particular, there are two critical problems underlying successful operation of sensor networks: (1) efficient methods for exchanging information between the nodes and (2) collaborative signal processing (CSP) between the nodes to gather useful information about the physical world. This article describes the key ideas behind the CSP algorithms for distributed sensor networks being developed at the University of Wisconsin (UW). We also describe the basic ideas on how the CSP algorithms interface with the networking/routing algorithms being developed at Wisconsin (UW-API). We motivate the framework via the problem of detecting and tracking a single maneuvering target. This example illustrates the essential ideas behind the integration between UW-API and UW-CSP algorithms and also highlights the key aspects of detection and localization algorithms. We then build on these ideas to present our approach to tracking multiple targets that necessarily requires classification techniques becomes a reality.
An enhanced vacuum switch

Operation of a vacuum switching gap in the magnetically delayed mode (with a series saturable inductor) has significantly improved the conduction characteristics of the gap, resulting in a switch more amenable to high-repetition-rate, short-pulse applications. Experiments have shown that the switching plasma fully permeates the interelectrode gap in the short interval following triggering but prior to the high current conduction phase, so that electrode heating is significantly reduced in a comparison to an otherwise similar vacuum switch. The switch plasma dissipated from the gap region in only a few microseconds, much faster than in the vacuum gap. A fast rate of current rise, with a time constant near 10 ns, has been obtained at 45 kV in a 50 Omega system. The results indicate that most, if not all, of the previously poor switching characteristics associated with vacuum gaps have been overcome. >
Adaptive Control of an Induction Motor with Magnetic Saturation Under Time-Varying Load Torque Uncertainty

A new global adaptive controller is designed for speed control induction motor with magnetic saturation, based on measurements of speed and stator currents. The designed partial state feedback controller is singularity free, and guarantees asymptotic tracking of smooth reference trajectories for the speed of the motor under time varying load torque. The new control algorithm generates estimates for unknown time varying load torque and rotor flux which asymptotically tracks and converges to their true values. The rotor flux modulus asymptotically tracks a desired reference signal which allows the motor to operate within its specifications. As in the field-oriented control scheme, the control algorithm generates references for the magnetizing flux component and for the speed component of the stator current. The control strategy yields decoupled rotor speed and rotor flux amplitude tracking control goals.
A capacity and minimum guarantee-based service class-oriented scheduler for LTE networks

Quality-of-service (QoS) requirements have always posed a challenge from scheduling perspective and it becomes more complicated with the emergence of new standards and applications. Classical techniques like maximum throughput, proportional fair, and exponential rule have been used in common network scenarios but these techniques fail to address diverse service requirements for QoS provisioning in long-term evolution (LTE). These QoS requirements in LTE are implemented in the form of delay budgets, scheduling priorities, and packet loss rates. Scheduler design for LTE networks therefore requires handling service class attributes but preciously proposed scheduling methods ignored service class-based design and focused more on single network prospect. To address service class requirements in LTE, we propose a modified radio resource management-based scheduler with minimum guarantee in the downlink following network capacity and service class attributes defined in LTE standard. The scheduler takes advantage of best available channel conditions while maintaining data rates corresponding to minimum resources guaranteed for all major classes including the best effort class. A method is proposed to determine the scheduling resource capacity of active users in LTE networks with an admission control to limit the number of users according to available resources. In addition to closely matched theoretical and simulated active users that can be accommodated in the system, promising results are provided for system delay, throughput, and user mobility.
Single-event transients in high-speed comparators

Single-event transients are investigated in comparators with switching speed below 80 ns, including one BiCMOS device. Modeling results show that the collapse of internal junctions after an ion strike delays the onset of collector current because of transient currents in the substrate that are not shielded by the buried layer. Transients in high-speed comparators are strongly affected by differential input voltage, but are suppressed in the bipolar comparators when the differential input voltage exceeds 200 mV. The BiCMOS device behaves differently because of the CMOS circuitry in latter stages.
Content-based Image Retrieval Using Gabor-Zernike Features

Content-based image retrieval (CBIR) is an important research area for manipulating large amount of image databases and archives. Extraction of invariant features is the basis of CBIR. This paper focuses on the problem of texture and shape feature extractions. We investigate texture feature and shape feature for CBIR by successfully combining the Gabor filters and Zernike moments (GF+ZM). GF is used for texture feature extraction and ZM extracts shape features. Comprehensive performance evaluation of our method is based on three different databases: face database, fingerprint database, and MPEG-7 shape database. The experimental results demonstrate that GF+ZM presents robustness to all of the three databases with the best average retrieval rate while the GF and ZM are limited for certain databases. GF is effective for face database and fingerprint database but is weak for MPEG-7 shape database. ZM achieves high retrieval rate for face database and MPEG-7 shape database but gives relatively low retrieval rate for fingerprint database.
New Academic Fields as Admittance-Seeking Social Movements: The Case of Strategic Management

Numerous histories of the early days of individual academic fields have been written, but scholars generally have stopped short of proposing generalizable frameworks or testable propositions for why these focal fields survived and prospered. We integrate logics from social movement theory and the sociology of science to model the rise of an aspiring academic community as an admittance-seeking social movement consisting of three major elements: differentiation, mobilization, and legitimacy building. We offer propositions based on in-depth analysis of the rise of a specific field—strategic management—within the administrative sciences.
Opponent modeling in interesting adversarial environments

We advance the field of research involving modeling opponents in interesting adversarial environments: environments in which equilibrium strategies are intractable to calculate or undesirable to use. We motivate the need for opponent models by showing how successful opponent modeling agents can exploit non-equilibrium strategies and strategies using equilibrium approximations. We examine the requirements for an opponent modeling agent, including the desiderata of a good model. We develop a new measurement which can be used to quantify how well our model can predict the opponent's behavior independently from the performance of the agent in which it resides. We show how this metric can be used to find areas of model improvement that would otherwise have remained undiscovered and demonstrate the technique for evaluating opponent model quality in the poker domain. The measurement can also be used to detect occasions when an opponent is not playing an equilibrium strategy, indicating potential opportunities for exploitation. We introduce the idea of performance bounds for classes of opponent models, present a method for calculating them, and show how these bounds are a function of only the environment and thus invariant over the set of all opponents an agent may face. We calculate the performance bounds for several classes of models in two domains: high card draw with simultaneous betting and a new simultaneous-move strategy game we developed. We describe how the performance bounds can aid selection of appropriate classes of models for a given domain as well as guide the level of effort that should be applied to developing opponent models in those domains. We expand the set of opponent modeling methods with new algorithms and study their performance empirically in several domains, including full scale Texas Hold'em poker. We explore opponent modeling improvement methods useful when the set of opponents we may face is unknown or unavailable. Using these techniques, we develop PokeMinn, an agent that learns to improve its performance by observing the opponent, even when the opponent is attempting to approximate equilibrium play. These methods also pave the way for performance optimization using genetic algorithms and efficient model queries using metareasoning.