cssi/SciSciGPT-SciSciNet huggingface dataset:
Estimating spatial interdependence in automobile type choice with survey data

In this article, we show that vehicle type ownership is spatially dependent at both the regional and household-level even after controlling for income and population density. We discuss reasons for the existence of spatial effects in vehicle ownership, and note potential implications for policymakers. Our results point to the importance of spatial relationships in transportation research and highlight the hazards of ignoring their role in affecting transportation outcomes. For example, if vehicle type choice is affected by neighborhood spillovers, agencies that regulate traffic flow and road safety could tailor their choice projections and policy tools to account for such interdependence.
Monoreflections of commutative rings with identity

It is shown that the category CRng-1, of all commutative rings with identity, together with all the ring homomorphisms that preserve the identity, has no proper monoreflective subcategories.
Mortality of eggs and larvae of the tobacco hornworm on jimson weed and various tobacco cultivars in Kentucky.

Survival of the tobacco hornworm, Manduca sexta (L.), from egg to prepupa was 0.8, 5.7 and 2.3% but survival from the 1st instar to the prepupa was 7.5, 6.5, and 3.0% when on Jimson weed, burley tobacco, and Tobacco Introduction (TI) 1298 respectively. These differences resulted primarily from differences in egg parasitism, which was high on Jimson weed, low on TI 1298, and nil on burley tobacco.
Development and acceleration of parallel chemical transport models

Improving chemical transport models for atmospheric simulations relies on future developments of mathematical methods and parallelization methods. Better mathematical methods allow simulations to more accurately model realistic processes and/or to run in a shorter amount of time. Parallelization methods allow simulations to run in less time, allowing scientists to use more accurate or more detailed simulations (higher resolution grids, smaller time steps).The STEM chemical transport model provides a large scale end-to-end application to experiment with running chemical integration methods and transport methods on GPUs. GPUs provide high computational power at a fairly cheap cost. The CUDA programming environment simplifies the GPU development process by providing access to powerful functions to execute parallel code. This work demonstrates the acceleration of a large scale end-to-end application on GPUs showing significant speedups. This is achieved by implementing all relevant kernels on the GPU using CUDA. Nevertheless, further improvements to GPUs are needed to allow these applications to fully exploit the power of GPUs.
NASA to build chemical release module

NASA's Marshall Space Flight Center, Huntsville, Alabama, has contracted for design, development, and manufacture of a self-contained, free-flying chemical release module for the first controlled, large-scale investigations of the dynamic phenomena that occur in the regions outside the earth's atmosphere. The contract calls for delivery of the chemical release module to Marshall Center for a mid-1983 launch of the space shuttle. The approximate value of the proposed contract is $9.5 million. For many years it has been theorized that solar winds, solar flares, and other phenomena that originate on the sun, directly affect our atmosphere through a series of dynamic processes in the earth's magnetosphere, ionosphere, and upper atmosphere. The difficulty in gathering information on these processes lies in the vastness of the region and the fact that all of this dynamic activity is invisible.
rHuEPO treatment improves brain and cognitive function of anemic dialysis patients

Twenty-four patients with chronic renal failure, stabilized on hemodialysis, were treated with recombinant human erythropoietin. Before treatment, all patients were anemic (mean Hct = 23.7%). Hematocrits reached normal levels (36.5%) after three months of treatment. Brain event-related potentials and neuropsychological tests were used to assess changes in brain and cognitive functions associated with the correction of anemia. Assessments were done prior to and after three and twelve months of rHuEPO treatment. The P3 component of the event-related potential increased in amplitude significantly with treatment, while its latency was unaffected. Of the four neuropsychological tests administered, scores on two improved significantly with treatment, and the other two approached significance. Taken together, these findings suggest that the correction of anemia to hematocrits near normal in uremic patients by rHuEPO treatment improves brain and cognitive function by raising levels of sustained attention, thus increasing speed and efficiency of scanning and perceptual-motor functions and enhancing learning and memory. These findings also suggest that anemia, either directly or indirectly, may impair brain function.
Improving Energy Efficiency at the Phelps Dodge Hidalgo Smelter

With the objective of increasing energy efficiencies in a flash furnace, an Arizona-based 500 ton-per-day oxygen plant was disassembled and relocated to the Phelps Dodge Hidalgo smelter in New Mexico. As projected by computer modeling, the expected effects of oxygen enrichment on the furnace heat balance were realized and improvements to boiler operation attained.
Efficient and effective classification of creditworthiness using ant colony optimization

This paper proposes a new technique for classification of creditworthiness based on Ant Colony Optimization (ACO). Our approach mimics the behavior of ants similar to the original ACO technique, but it encompasses new formulas for calculating heuristic values and for selecting pheromone accumulation path. We compare the performance of our ACO-based technique with the best known ACO-based implementation called AntMiner+. The results show that our ACO-based technique yields a 98.6% accuracy for both training and testing, whereas AntMiner+ yields only 71.8%. This significant improvement shows that a carefully crafted heuristic formula and attention to the characteristics of the credit scoring problem are vital to the quality of classification rules extracted by the ACO-based techniques.
Preparation of high-titre anti-P1 sera for blood typing in man.

Abstract For the last 25 years, antisera for testing P 1 in man have been obtained by i.v. injections in goats using hydatid cyst fluid from livers of pigs infected by Echinococsus granulosus. Due to the fact that this antigen has become very rare today, efforts have been made by the authors to substitute it by different antigens and to save antigen by modifying the technique of immunisation as well. By this, very high titres up to 1: 4096 could be reached after specification absorption.
Identification of the sites of N-linked glycosylation on the follicle-stimulating hormone (FSH) receptor and assessment of their role in FSH receptor function.

The FSH receptor (FSHR) contains a large extracellular domain in which exist three potential sites for N-linked glycosylation. A truncated form of the FSHR representing only the extracellular domain was created and expressed in mammalian cells. We show that this truncated receptor is glycosylated, through the carbohydrates are not as fully processed as those of the full-length receptor. This truncated receptor, which remains intracellular, binds FSH with an affinity comparable to that of the full-length FSHR. Therefore, although other regions of the FSHR may contribute to hormone binding, the extracellular domain alone can confer high affinity binding. The above results suggest that N-linked FSHR carbohydrates may, in some way, be required for FSH binding. Therefore, further experiments, done in the context of the full-length receptor, were performed to determine the actual sites of glycosylation in the FSHR as well as to elucidate their role in the functions of the FSHR. Site-directed mutagenesis was don...
Ammonium interactions with proteins

1. 1.|Hydrogen-bonding of NH4+ to bovine serum albumin and bovine and equine α-globulins was detected by infrared spectroscopy. NH4+ caused perturbations of the NH stretching mode at 3300 cm−1 of films of proteins cast from solutions of NH4Cl. Mixing of KCl with NH4Cl reduced the perturbation. 2. 2.|The interaction of NH4+ with α-globulins caused them to lose stability to heating. The specific viscosity of solutions of bovine serum albumin was decreased by NH4Cl or KCl but was increased by NaCl, acetate salts, or urea at high concentrations. The extent of tryptic digestion of bovine serum albumin was decreased in NH4Cl solutions but increased in 6 M urea solutions in comparison to distilled water.
Deep brain stimulation of the ventral hippocampus restores deficits in processing of auditory evoked potentials in a rodent developmental disruption model of schizophrenia

Existing antipsychotic drugs are most effective at treating the positive symptoms of schizophrenia but their relative efficacy is low and they are associated with considerable side effects. In this study deep brain stimulation of the ventral hippocampus was performed in a rodent model of schizophrenia (MAM-E17) in an attempt to alleviate one set of neurophysiological alterations observed in this disorder. Bipolar stimulating electrodes were fabricated and implanted, bilaterally, into the ventral hippocampus of rats. High frequency stimulation was delivered bilaterally via a custom-made stimulation device and both spectral analysis (power and coherence) of resting state local field potentials and amplitude of auditory evoked potential components during a standard inhibitory gating paradigm were examined. MAM rats exhibited alterations in specific components of the auditory evoked potential in the infralimbic cortex, the core of the nucleus accumbens, mediodorsal thalamic nucleus, and ventral hippocampus in the left hemisphere only. DBS was effective in reversing these evoked deficits in the infralimbic cortex and the mediodorsal thalamic nucleus of MAM-treated rats to levels similar to those observed in control animals. In contrast stimulation did not alter evoked potentials in control rats. No deficits or stimulation-induced alterations were observed in the prelimbic and orbitofrontal cortices, the shell of the nucleus accumbens or ventral tegmental area. These data indicate a normalization of deficits in generating auditory evoked potentials induced by a developmental disruption by acute high frequency, electrical stimulation of the ventral hippocampus.
The structure of the oceanic crust off southern Peru determined from an ocean bottom seismometer

Abstract An oceanic crustal model has been produced for the Nazca plate south of the Nazca Ridge prior to subduction into the Peru-Chile Trench at 18°S latitude. Consistent delays of the P n arrivals and a discontinuity in the tau- p curve indicate a low-velocity zone at the base of the crust. Observed upper mantle velocities are low; however, the mantle velocity increases with depth, at least to 20 km, to a value of 8.5 km/s. A possible petrological cause for the low-velocity zone is partially serpentinized peridotite; however, no clear refracted shear waves were observed to constrain this interpretation.
Microstructural toughening mechanisms in γ-TiAl · 20 pct TiCb as determined by FRASTA

The mechanisms of toughening in an intermetallic matrix composite were determined by FRASTA, a technique that reconstructs microfailure details of a fracture event by comparing the topographies of conjugate fracture surfaces. Graphic portrayals of the interaction of a crack front with microstructure features are presented for a forged gamma titanium aluminide reinforced with 20 vol pct, 300-µm-diameter, 30-µm-thick TiCb platelets. The threefold toughness increase relative to unreinforced material is attributed to (1) drag on the crack front by the TiCb platelets, (2) bridging of the crack faces by the TiCb platelets, and (3) deflection of the crack front by microcracks in the process zone that nucleate and grow out-of-plane at TiCb platelets. The fractographic results explain discrepancies between measured and predicted toughnesses, provide the mechanistic understanding and microfailure data needed to develop more reliable models, and suggest microstructural modifications for developing more fracture-resistant materials.
Human Resource Practices in State Government: Findings from a National Survey

What are states doing with respect to human resource practices to improve government operations? Using data collected by the Government Performance Project, this article identifies emerging trends and innovations in state personnel systems. Specifically, it provides a national comparison in the areas of personnel authority, workforce planning, selection, classification, and performance management. Results show that many states are delegating authority for personnel functions to agencies and managers, shifting their human resource missions to being more proactive and collaborative with agencies, and adopting performance management systems that integrate organizational and individual goals. In short, many states are investing considerable resources to modernize their human resource management systems.
Two-dimensional polyacrylamide gel electrophoresis of acid extractable nuclear proteins of normal rat liver and Novikoff hepatoma ascites cells.

Abstract The nuclear proteins of normal rat liver and Novikoff hepatoma nuclei were extracted with 0.4 N H 2 SO 4 and subjected to two-dimensional polyacrylamide gel electrophoresis. A total of 98 protein components were found in the liver extract and 111 components in the tumor extract. A comparison of the patterns obtained revealed 11 qualitative differences and 5 quantitative differences.
Women's Employment Rights in China: Creating Harmony for Women in the Workforce

This Note explores the global problem of gender-based labor inequality as exemplified in China. China’s historic and cultural framework, the efforts the Chinese government has made to coordinate with the global community on women’s rights initiatives, and recent legislation passed at both national and local levels in China provide an interesting case study for countries facing gender inequality in the workplace. The items of legislation, though sometimes drafted using international treaties as a framework, contain unique provisions that provide protections for Chinese women that are not seen elsewhere in the world. Additionally, the Chinese government’s current political goal of achieving a harmonious society signals potentially forthcoming advancements in workplace gender equality.
Using liquid waste streams as the moisture source during the hydrothermal carbonization of municipal solid wastes

Hydrothermal carbonization (HTC) is a thermal conversion process that can be an environmentally beneficial approach for the conversion of municipal solid wastes to value-added products. The influence of using activated sludge and landfill leachate as initial moisture sources during the carbonization of paper, food waste and yard waste over time at 250°C was evaluated. Results from batch experiments indicate that the use of activated sludge and landfill leachate are acceptable alternative supplemental liquid sources, ultimately imparting minimal impact on carbonization product characteristics and yields. Regression results indicate that the initial carbon content of the feedstock is more influential than any of the characteristics of the initial liquid source and is statistically significant when describing the relationship associated with all evaluated carbonization products. Initial liquid-phase characteristics are only statistically significant when describing the solids energy content and the mass of carbon in the gas-phase. The use of these alternative liquid sources has the potential to greatly increase the sustainability of the carbonization process. A life cycle assessment is required to quantify the benefits associated with using these alternative liquid sources.
Compartmental Architecture and Dynamics of Hematopoiesis

BACKGROUND: Blood cell formation is maintained by the replication of hematopoietic stem cells (HSC) that continuously feed downstream "compartments" where amplification and differentiation of cells occurs, giving rise to all blood lineages. Whereas HSC replicate slowly, committed cells replicate faster as they become more differentiated. METHODOLOGY/SIGNIFICANT FINDING: We propose a multi-compartment model of hematopoiesis, designed on the principle of cell flow conservation under stationary conditions. Cells lost from one compartment due to differentiation are replaced by cells from the upstream compartment. We assume that there is a constant relationship between cell input and output in each compartment and fix the single parameter of the model using data available for granulocyte maturation. We predict that approximately 31 mitotic events separate the HSC from the mature cells observed in the circulation. Besides estimating the number of compartments, our model allows us to estimate the size of each compartment, the rate of cell replication within each compartment, the mean time a given cell type contributes to hematopoiesis, the amplification rate in each compartment, as well as the mean time separating stem-cell replication and mature blood-cell formation. CONCLUSIONS: Despite its simplicity, the model agrees with the limited in vivo data available and can make testable predictions. In particular, our prediction of the average lifetime of a PIG-A mutated clone agrees closely with the experimental results available for the PIG-A gene mutation in healthy adults. The present elucidation of the compartment structure and dynamics of hematopoiesis may prove insightful in further understanding a variety of hematopoietic disorders.
Follow-up of methadone-treated and untreated narcotic-dependent women and their infants: health, developmental, and social implications.

This study compares the first year's health, neurodevelopmental status, and environment of infants of drug-dependent mothers attending methadone programs during pregancy with those of drug-dependent mothers not enrolled in treatment programs (untreated). Both groups were also compared with drug-free controls. During pregnancy, the use of heroin and other psychoactive drugs was common among patients using methadone. Neonatal abstinence syndrome was of longest duration in the methadone group. Infants of both drug groups were smaller at birth, had more neonatal infections, and were viewed as more difficult to care for after nursery discharge than were those of drug-free mothers. On follow-up, mean developmental scores were within the normal range for all groups. The untreated drug-dependent group was more hypertonic than the methadone group, and a high rate of transient or minor motor disturbances and poor attention span was found in both drug groups. The behavior of methadone-treated women during pregnancy and the postnatal period closely resembled that of drug-free controls, and contrasted with untreated drug-dependent women. Methadone-treated women had a high degree of compliance with antepartum care, and 80% continued in the role of parent through the first year. Further investigation will determine whether the consistency of parenting will continue and whether it will enhance the development of their children.
Poetry vs. Philosophy

us with the example of Vaclav Havel, stories about particular people and their experiences constitute an important corrective for the dehumanizing effects of abstract theory or generalization in politics. As Wilson Carey McWilliams shows in the case of Mark Twain, comedy unmasks human pretensions to have final answers to the great questions; but it also "shows that ignorance and illogic are laughable, and that amorality and radical selfishness produce only a ludicrous caricature of a human being." Students of politics and literature may doubt our ability to answer the great questions about justice and the possibility of human happiness, either individual or communal, but we think that it is essential that
A novel technique for extracting parametric models from MEM resonator test data

This paper reports an innovative test and modeling procedure that is well-suited to high-Q resonators and overcomes several shortcomings of FFT-based approaches. The novel technique uses excitation-response data to generate parametric resonator models in the time-domain. The models possess the following advantages: immunity to parasitic coupling, a spectral resolution that is not limited by record length, and the ability to clearly distinguish nearly degenerate and degenerate modes by using multi-input, multi-output data sets. The parametrization readily yields transfer functions, natural frequencies, time constants and insight into mode shapes.
A level set approach to a unified model for etching, deposition, and lithography I: algorithms and two-dimensional simulations

Abstract We apply a level set formulation to the problem of surface advancement in a two-dimensional topography simulation of deposition, etching, and lithography processes in integrated circuit fabrication. The level set formulation is based on solving a Hamilton-Jacobi type equation for a propagating level set function, using techniques borrowed from hyperbolic conservation laws. Topological changes, corner and cusp development, and accurate determination of geometric properties such as curvature and normal direction are naturally obtained in this setting. The equations of motion of a unified model, including the effects of isotropic and unidirectional deposition and etching, visibility, surface diffusion, reflection, and material dependent etch/deposition rates are presented and adapted to a level set formulation. The development of this model and algorithm naturally extends to three dimensions in a straightforward manner and is described in part II of this paper (in press).
Roles for host factors in plant viral pathogenicity

The simple, obligate nature of viruses requires them to usurp or divert cellular resources, including host factors, away from their normal functions. The characterization of host proteins, membranes, and nucleic acids that are implicated in viral infection cycles, together with other recent discoveries, is providing fundamental clues about the molecular bases of viral susceptibility. As viruses invade susceptible plants, they create conditions that favor systemic infections by suppressing multiple layers of innate host defenses. When viruses meddle in these defense mechanisms, which are interlinked with basic cellular functions, phenotypic changes can result that contribute to disease symptoms.
LOGJAM: a scalable unified log file archiver

Log files are a necessary record of events on any system. However, as systems scale, so does the volume of data captured. To complicate matters, this data can be distributed across all nodes within the system. This creates challenges in ways to obtain these files as well as archiving them in a consistent manner. It has become commonplace to develop a custom written utility for each system that is tailored specifically to that system. For computer centers that contain multiple systems, each system would have their own respective utility for gathering and archiving log files. Each time a new log file is produced, a modification to the utility is necessary. With each modification, risk of errors could be introduced as well as spending time to introduce that change. This is precisely the purpose of logjam. Once installed, the code only requires modification when new features are required. A configuration file is used to identify each log file as well as where to harvest it and how to archive it. Adding a new log file is as simple as defining it in a configuration file and testing can be performed in the production environment.
Alteration in timing of cell differentiation resulting from cell interactions during development of the cellular slime mold, Dictyostelium discoideum.

Abstract The effect of cell interactions on the timing of cell differentiation of Dictyostelium discoideum was studied by monitoring spore differentiation in chimeric aggregates composed of two cell populations, one of which was cycloheximide resistant. Chimeras were constructed with cells of a rapidly developing strain, FR-1, and cells of a normally developing cycloheximide resistant strain, CR-2. CR-2 cells formed spores 4 to 5 hr prematurely while spore formation by FS-1 cells was delayed by 1 hr. The two cell populations formed spores 3 hr apart from each other. FS-1 spores were localized to the enlarged bases of the fruiting bodies, whereas CR-2 spores were found in the apical structures. Chimeras were also constructed with cells of two normally developing strains, CR-2 and A3, one population of which had been dissociated at 8.5 hr and the other at 19 hr of development. The 19-hr cells formed spores 2 hr late and 8.5-hr cells 2 to 4 hr prematurely. The two cell populations formed spores within 1 hr of each other although they were asynchronous by 10.5 hr at the time of mixing. These chimeras formed normal fruiting bodies. The results indicate that the timing of cell differentiation is altered by the presence of cells developing at a different rate.
Mantle eclogite and carbonate as sources of sodic carbonatites and alkalic magmas

At mantle pressures, partial melts of peridotite + CO2 are carbonate-rich, but contain insufficient sodium to form most carbonatites and associated silicate magmas. A possible source rock is eclogite, and extrapolations from experiments suggest that eclogite + CO2 will coexist with melt along geotherms of low heat flow. Thermochemical calculations yield high carbonate activities, and imply that the melt is carbonatitic. The melt can be modelled in the system jadeite–calcite–CO2 and will, on emplacement, form mineral assemblages characteristic of a wide range of alkalic rocks. The tectonic settings of carbonatites are consistent with an origin as partial melts of eclogite + carbonate + CO2 under areas of low surface heat flow, and suggest that carbonatite emplacement is not related to mantle hotspots.
Migratory behaviour and range in Atlantic cod: inference from a century of tagging

A century of tagging experiments on 174 Atlantic cod (Gadus morhua) groups is reviewed and the frequency and spatial distribution of four migratory behaviours documented. Of all cod groups, 41% were categorized as sedentary, 18% as accurate homers, 20% as inaccurate homers and 20% as dispersers (ranging over large areas without recognizable return migrations). All behaviours occurred over the full spatial range of cod. Coastal groups did not differ significantly from offshore (shelf) groups in the relative frequency of migratory behaviours. However, the north-east Atlantic had more sedentary and accurate homing groups than did the north-west Atlantic, which had more dispersing groups. Overall, sedentary cod groups had lower maximum historical biomass than did other groups, confirming that migration/dispersal begets abundance. Maximum historical biomass was strongly related to the area occupied [log (biomass, tonnes)] ¼ 1.58 log (range, km 2 ) + 1.529; r 2 ¼ 0.9), irrespective of migratory type (for 23 major groups a total of 22 million tonnes over 3.3 million km 2 with an average density of 7 tonnes km )2 ). Historical densities were not related to area occupied, although all large groups exhibited high densities (10–12 tonnes km )2 ; smaller groups had a wide range of density). The four migratory strategies in cod enable entrainment by diverse physical, oceanographic and biological ecosystem properties, and is key to cod success in the North Atlantic.
Removing Laver functions from supercompactness arguments

We show how the use of a Laver function in the proof of the consistency, relative to the existence of a supercompact cardinal, of both the Proper Forcing Axiom and the Semiproper Forcing Axiom can be eliminated via the use of lottery sums of the appropriate partial orderings. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Some Additional Data on Dissertations in Political Science, 1960 and 1970–72

In the fall '72 issue of PS, Walfred H. Peterson, Stephen Blank, and William C. Yoels have drawn some interesting data and interpretations from APSA's annual listing of completed political science dissertations.1 Their focus on data related to Ph.D. output, interest distribution within sub-fields, and "the fate of the Ph.D." clearly reflect the concern of the advanced scholar who is interested in the general development of the discipline.
Effects of alkyl-substituted γ-butyrolactones and succinimides on the evoked and spontaneous activity of hippocampal slices in vitro

Abstract Alkyl-substituted and unsubstituted derivatives of γ-butyrolactone (GBL), γ-hydroxybutyrate (GHB), and succinimide were tested for their effects on the evoked potential (EP) and spontaneous activity of hippocampal slices incubated in vitro . When tested alone, only β-ethyl-β-methyl-GBL (β-EMGBL) and tetramethylsuccinimide (TMSM) had any effect, producing greatly augmented EPs and spontaneous epileptiform discharges. The nonexcitatory drugs were also tested for the ability to block the excitation produced by β-EMGBL, TMSM, and penicillin. The unsubstituted compounds had no effect on the augmented EP induced by any of the convulsants. The α-ethyl-α-methyl-substituted GBL (α-EMGBL) and ethosuximide (ESM), blocked the augmented EP induced by β-EMGBL and TMSM but not that induced by penicillin. The spontaneous activity induced by all three excitatory agents was blocked by GHB. Unsubstituted succinimide had no effect on spontaneous activity. The spontaneous activity produced by β-EMGBL and TMSM was blocked by α-EMGBL, but ESM blocked only that induced by TMSM. Neither α-EMGBL nor ESM blocked the spontaneous activity produced by penicillin. We conclude that the ability to block the EP more closely parallels in vivo anticonvulsant activity whereas effects on the spontaneous activity may be more related to neuronal depressant effects. The alkyl-substituted GBLs and succinimides had very similar, albeit not identical, effects on incubated hippocampal slices. That may indicate that they have a similar but not a common mechanism of action.
Spin Polarization of the Resonant Two-Hole Bound State in Ni Photoemission

We calculate the spin polarization of the 6-eV resonant satellite in Ni $3d$-band photoemission. The satellite is identified with the $3{d}^{8}$ configuration, and the resonant process involves the absorption $3{p}^{6}3{d}^{9}\ensuremath{\rightarrow}3{p}^{5}3{d}^{10}$ followed by the super---Coster-Kronig transition $3{p}^{5}3{d}^{10}\ensuremath{\rightarrow}3{p}^{6}3{d}^{8}\ensuremath{\epsilon}l$. The spin-up (majority) to spin-down (minority) intensity ratio is found to be approximately 4: 1 for the resonant process, whereas nonresonant Auger decay is found to be essentially unpolarized.
Probabilistic Approach to Determining Unbiased Random-coil Carbon-13 Chemical Shift Values from the Protein Chemical Shift Database

We describe a probabilistic model for deriving, from the database of assigned chemical shifts, a set of random coil chemical shift values that are “unbiased” insofar as contributions from detectable secondary structure have been minimized (RCCSu). We have used this approach to derive a set of RCCSu values for 13Cα and 13Cβ for 17 of the 20 standard amino acid residue types by taking advantage of the known opposite conformational dependence of these parameters. We present a second probabilistic approach that utilizes the maximum entropy principle to analyze the database of 13Cα and 13Cβ chemical shifts considered separately; this approach yielded a second set of random coil chemical shifts (RCCS $$_{{\rm max}\hbox{-}{\rm ent}}$$ ). Both new approaches analyze the chemical shift database without reference to known structure. Prior approaches have used either the chemical shifts of small peptides assumed to model the random coil state (RCCSpeptide) or statistical analysis of chemical shifts associated with structure not in helical or strand conformation (RCCS $$_{{\rm struct}\hbox{-}{\rm stat}}$$ ). We show that the RCCS $$_{{\rm max}\hbox{-}{\rm ent}}$$ values are strikingly similar to published RCCSpeptide and RCCS $$_{{\rm struct}\hbox{-}{\rm stat}}$$ values. By contrast, the RCCSu values differ significantly from both published types of random coil chemical shift values. The differences (RCCSpeptide−RCCSu) for individual residue types show a correlation with known intrinsic conformational propensities. These results suggest that random coil chemical shift values from both prior approaches are biased by conformational preferences. RCCSu values appear to be consistent with the current concept of the “random coil” as the state in which the geometry of the polypeptide ensemble samples the allowed region of (ϕ,ψ)-space in the absence of any dominant stabilizing interactions and thus represent an improved basis for the detection of secondary structure. Coupled with the growing database of chemical shifts, this probabilistic approach makes it possible to refine relationships among chemical shifts, their conformational propensities, and their dependence on pH, temperature, or neighboring residue type.
Mass spectrometric quantitation and analysis of leukotrienes and other 5-lipoxygenase metabolites

Abstract Detailed studies fo the 5-lipoxygenase pathway of arachidonic acid metabolism in vivo is a difficult challenge, but nonetheless, an important pursuit. The leukotriense are perplexing compounds to quantitate due, in part, to their production in very small quantities by only certain cells, as well as to their chemical/biochemical instability. Several mass spectrometric techniques have been developed to quantitate 5-hydroxyeicosatetraenoic acid (5-HETE) and leukotriene b 4 (LTB 4 ). The mass spectral properties of terbutyldimethylsilyl derivatives of LTB 4 are reported here which are quite favorable for electron impact ionization. Catalytic reduction of LTB 4 prior to derivatization greatly improved capillary gas chromatographic behavior as well as electron impact mass spectral properties. Subpicomole quantities could be readily detected by selected ion recording of the M-57 ion, which is the most abundant ion in the mass spectrum. Lipoxygenase products labeled with oxygen-18 at the carboxyl moiety are uniquely stable to catalytic reduction and, thus, may serve as useful internal standards.
Embryonic Stem Cells with a Disrupted GD3 Synthase Gene Undergo Neuronal Differentiation in the Absence of b-Series Gangliosides

Abstract The dramatic changes in the expression of GD3 and other b-series gangliosides during neuronal development and morphogenesis have led to a widely held belief that these gangliosides may be necessary for neuronal differentiation. To determine directly if GD3 and b-series gangliosides are required for neuronal differentiation, we have produced embryonic stem (ES) cells with both alleles of the GD3 synthase gene (GD3S) disrupted by successive rounds of gene targeting. The double-targeted ES cells were deficient in GD3 synthase activity and did not synthesize b-series gangliosides. Despite this deficit, the GD3S(−/−) ES cells could be induced to undergo neuronal differentiation. Neuronally differentiated wild-type and GD3S(−/−) ES cells formed a complex neurite network around the embryoid bodies. Both types of neuronal cells expressed the axon-specific cytoskeletal proteins, neurofilament-M, and growth-associated protein-43 as well as the dendrite-specific marker, microtubule-associated protein-2. Our results indicate that GD3 synthase and b-series gangliosides are not necessary for the neuronal differentiation of uncommitted precursor cells.
The genetic structure of personality: II. Genetic item analysis of the EPQ.

Abstract Most studies of the inheritance of personality have performed genetic analysis of scale scores, which will sometimes give a misleading impression of what is inherited. Item genetic analysis, where this is focused on differences in genetic architecture rather than merely differences in item heritability, should guide the development of genetically homogeneous scales. Item genetic analyses of the EPQ were performed, using data from 3810 pairs from the Australian Twin Register. All but three items exhibited significant genetic variance. Genetic dominance was found for a majority of items from the Extraversion and Neuroticism scales, although the dominance effects were weak for N items, particularly in females. Shared environmental effects were found for items from the Lie and Psychoticism scales; for P items they were strong in males but weak in females. These differences in genetic architecture and genotype x sex interaction should permit use of multivariate item genetic analysis to identify the underlying genetic structure of the personality dimensions assessed by the EPQ.
Prognostic significance of syndecan 1 (CD 138) in oral mucosal dysplasia

138) IN ORAL MUCOSAL DYSPLASIA. N. Narayana, M. Fornatora, R. Reich, P.D. Freedman, Oral Pathology Lab Inc, Flushing, NY, and Temple University School of Dentistry, Philadelphia, Pa. The microscopic grading of dysplasia has remained subjective, with poor intrarater and interexaminer reliability. The need for an objective marker to help standardize the grading of dysplasia cannot be overemphasized. Syndecan 1 (S1), originally thought to be a cell surface receptor assisting in cell surface interaction and differentiation, has been extensively studied. S1 expression has been related to the level of differentiation of epithelial cells, with positive expression associated with favorable prognosis of squamous cell carcinoma (SCC). A pilot study was undertaken to determine the prognostic significance of S1 in oral mucosal dysplasia. Methods. Five patients (mean patient age [MPI], 71.8 years) with epithelial dysplasia that recurred as SCC (MPI, 76.6 years) and 4 patients (MPA, 73.5 years) with mild/moderate epithelial dysplasia recurring as severe dysplasia (MPI, 78.5 years) were included in the study. The control groups for the staining pattern and intensity of S1 contained 2 patients each (MPI, 64 years) with normal mucosa and poorly differentiated SCC (MPI, 73.5 years). Immunohistochemical staining for S1 (Clone B-B4; Serotec, Raleigh, NC) was performed on formalin-fixed tissue. Results. The staining of normal mucosa in the present study was similar to that reported in the literature, with increasing intensity from basal cells to spinous cells and no staining of the keratin layer. Poorly differentiated SCC also exhibited epithelial cell cytoplasmic and cell membrane staining. This pilot study revealed no appreciable difference in the pattern and intensity of S1 staining of basal and spinous cells among normal mucosa, varied dysplasias, and SCC. We expected an altered pattern of S1 staining, which could not be demonstrated, because of the maturational abnormalities in dysplastic epithelium,. In view of these results, it can be concluded that S1 does not seem to have prognostic significance in the grading of oral mucosal dysplasia.
1400 FREQUENCY AND TIDAL VOLUME CHANGES IN HIGH RISK IN FANTS IN RESPONSE TO INHALED CARBON DIOXIDE

1400 FREQUENCY AND TIDAL VOLUME CHANGES IN HIGH RISK IN FANTS IN RESPONSE TO INHALED CARBON DIOXIDE
A comparison of solution methods for the assortment problem

The problem of economically cutting a required bill of material out of standard size stock pieces is shared by the metal, leather, glass, electronic, shipbuilding, and lumber industries. One of the problems in this area is the assortment problem; that is, determining the best combination of stock sizes to keep in inventory to cut a single known (deterministic) bill of material. This problem includes determining the dimensions or the stock pieces as well as the number of unique sizes to stock. In this research a comparison is made between three common heuristic methods for solution of the assortment problem and the introduction of the application of optimization homotopy to the assortment problem, a method developed for the solution of stochastic problems. It is found that while utilizing a specific combination of nesting and sequencing algorithms, the three heuristic methods work very well for simpler problems, and as the complexity of the problem increases optimization homotopy becomes more advantageous.
Insights and issues with simulating terrestrial DOC loading of Arctic river networks

Terrestrial carbon dynamics influence the contribution of dissolved organic carbon (DOC) to river networks in addition to hydrology. In this study, we use a biogeochemical process model to simulate the lateral transfer of DOC from land to the Arctic Ocean via riverine transport. We estimate that, over the 20th century, the pan-Arctic watershed has contributed, on average, 32 Tg C/yr of DOC to river networks emptying into the Arctic Ocean with most of the DOC coming from the extensive area of boreal deciduous needle-leaved forests and forested wetlands in Eurasian watersheds. We also estimate that the rate of terrestrial DOC loading has been increasing by 0.037 Tg C/yr2 over the 20th century primarily as a result of climate-induced increases in water yield. These increases have been offset by decreases in terrestrial DOC loading caused by wildfires. Other environmental factors (CO2 fertilization, ozone pollution, atmospheric nitrogen deposition, timber harvest, agriculture) are estimated to have relatively small effects on terrestrial DOC loading to Arctic rivers. The effects of the various environmental factors on terrestrial carbon dynamics have both offset and enhanced concurrent effects on hydrology to influence terrestrial DOC loading and may be changing the relative importance of terrestrial carbon dynamics on this carbon flux. Improvements in simulating terrestrial DOC loading to pan-Arctic rivers in the future will require better information on the production and consumption of DOC within the soil profile, the transfer of DOC from land to headwater streams, the spatial distribution of precipitation and its temporal trends, carbon dynamics of larch-dominated ecosystems in eastern Siberia, and the role of industrial organic effluents on carbon budgets of rivers in western Russia.
Purified methoxychlor stimulates the reproductive tract in immature female mice.

Abstract Methoxychlor is an estrogenic pesticide currently used as a substitute for DDT. The estrogenic effects of 98% pure methoxychlor or base-washed pure methoxychlor were examined on reproductive organs of immature mice and compared to control and estradiol-treated mice. Within 24 hours of birth, neonatal mice received 14 daily intraperitoneal injections of one of the following chemicals: sesame oil only, 10.0 μg of 17-β estradiol, or 0.05 mg, 0.5 mg, or 1.0 mg of 98% pure methoxychlor, or 1.0 mg base-washed 98% pure methoxychlor. Equal doses (1.0 mg) of 98% pure or base-washed methoxychlor stimulated the reproductive organs of immature females such that the effects closely resembled those seen after estradiol treatments. In comparison to control mice, these pesticide treatments also induced precocious vaginal opening, persistent vaginal cornification, increased reproductive tract weights, and epithelial hypertrophy in both the vagina and uterus. However, only estradiol treatments significantly elevated albumin levels in the uterine fluid of the immature mice while the highest methoxychlor doses significantly increased the uterine cell heights when compared to all other groups.
Characterization and analysis of infrared images

Stokes images in the long-wave infrared (LWIR) and methods for processing polarimetric data continue to be areas of interest. Stokes images which are sensitive to geometry and material differences are acquired by measuring the polarization state of the received electromagnetic radiation. The polarimetric data from Stokes images may provide enhancements to conventional IR imagery data. It is generally agreed that polarimetric images can reveal information about objects or features within a scene that are not available through other imaging techniques. This additional information may generate different approaches to segmentation, detection, and recognition of objects or features. Previous research where horizontal and vertical polarization data is used supports the use of this type of data for image processing tasks. In this work we analyze a sample polarimetric image to show both improved segmentation of objects and derivation of their inherent 3-D geometry.
Biochemical properties of brain somatostatin receptors

The physical properties of brain and pituitary somatostatin receptors were characterized using photocrosslinking techniques. Somatostatin receptors in rat corpus striatum and anterior pituitary membranes were covalently bound to the non-reducible somatostatin analog, [125I]CGP 23996, using the crosslinking agent n-hydroxysuccinimidyl-4-azidobenzoate and ultraviolet light. In striatal membranes, a protein of 60,000 mol. wt was labeled by [125I]CGP 23996. The binding was potently inhibited by somatostatin analogs but not by other biologically active peptides. The labeling of the 60,000 mol. wt protein by [125I]CGP 23996 was diminished by guanine triphosphate gamma thiol, which is consistent with the labeling of a somatostatin receptor coupled to guanine triphosphate binding proteins. The migration of the [125I]CGP 23996 labeled 60,000 mol. wt protein in native sodium dodecyl sulfate-gels was not affected by the reducing agent dithiothreitol, indicating that there is a general lack of disulfide bridges in the striatal somatostatin receptor. The striatal somatostatin receptor was solubilized with the detergent 3-[(3-cholamidopropyl)-dimethylaminoio]-1-propanesulfonate and specifically bound to the lectin wheat germ agglutinin, suggesting that the striatal somatostatin receptor is a glycoprotein. [125I]CGP 23996 also labeled a 60,000 mol. wt protein in anterior pituitary membranes. The characteristics of [125I]CGP 23996 binding to anterior pituitary membranes were consistent with the labeling of a somatostatin receptor. Interestingly, a comparison of the [125I]CGP 23996 labeled material from striatal and anterior pituitary membranes by two-dimensional polyacrylamide gel electrophoresis revealed the presence of several striatal somatostatin receptors of varying charge (pI values between 6 and 6.5) but only a single pituitary receptor. These findings indicate that physical differences may exist between subtypes of somatostatin receptors.
Evidence of alternate attractors from a whole-ecosystem regime shift experiment

Ecosystems sometimes shift between different states or dynamic regimes. Theory attributes these shifts to multiple ecosystem attractors. However, documenting multiple ecosystem attractors is difficult, particularly at spatial and temporal scales relevant to ecosystem management. We manipulated the fish community of a lake with the goal of causing trophic cascades and shifting the food web from a planktivore-dominated state to an alternate piscivore-dominated state. We evaluated evidence that the shifts in the fish community comprise alternate attractors using two complementary approaches. First, we calculated phase space trajectories to visualize the shift between attractors. Second, we computed generalized autoregressive conditional heteroskedasticity (GARCH) models and the Brock–Dechert–Scheinkman (BDS) test for linearity. The reconstructed phase space trajectories show the system departing a point attractor, entering a limit cycle, and then shifting to a new point attractor. The GARCH and BDS results indicate that linear explanations are not sufficient to explain the observed patterns. The results provide evidence for alternate attractors based on high-frequency time series of field measurements.
Evidence for withdrawal from caffeine by rats.

Abstract Injections of caffeine produced avoidance of a novel flavor. Rats which had previously received injections of caffeine on each of twelve days avoided a novel solution which had been associated with the absence of caffeine. This and other controls suggest that physiological withdrawal from caffeine is the mechanism for this avoidance.