cssi/SciSciGPT-SciSciNet huggingface dataset:
Thymosin α1-induced modulation of cellular responses and functional T-cell subsets in mice with experimental autoimmune thyroiditis

The effects of Ta-1, a peptide constituent of thymosin fraction 5, were studied on murine autoimmune thyroiditis using two congenic strains of mice, B10.Br (Br) and B10.D2 (D2), which are sensitive and resistant to experimental autoimmune thyroiditis (EAT) induction, respectively. EAT was induced by either 2 weekly iv injections of mouse thyroglobulin with adjuvant lipopolysaccharide (LPS) or intradermal injection of thyroglobulin mixed with complete Freund's adjuvant (CFA). The criteria for induction and intensity of thyroiditis were the level of lymphoid infiltration in the thyroid gland and the titer of anti-thyroglobulin antibodies. Ta-1 was given in 5 or 10 daily sc injections in doses ranging from 0.0001 to 0.1 microgram/injection. The injections were commenced at varying intervals from the 1st to the 4th week after immunization. T-Cell subsets in the spleens were determined 2 weeks after the first antigen injection and thyroid infiltration was determined 3 weeks later. Treatment with Ta-1 between the two antigen injections increased the level of thyroiditis in resistant mice, but had no effect in sensitive mice. Treatment for the first 2 weeks had similar effects in resistant mice, but also suppressed thyroiditis in the sensitive strain. Later treatments, during the 3rd and 4th weeks after immunization also revealed immunomodulating properties of Ta-1, with a suppressing effect on thyroiditis in sensitive mice and an enhancing effect in the resistant strain. Both effects of Ta-1 were dose dependent. The effects of Ta-1 on the individual phenotypes were also dose dependent. The dose of 0.01 microgram greatly lowered the percentages of Lyt-2+3+ cells in D2 mice and mildly increased the percentages in Br mice, but did not change the Lyt-1+ cell level in either strain. On the other hand, the dose of 0.001 microgram greatly increased the percentage of Lyt-1+ cells in D2 mice and mildly decreased it in the Br strain, but did not alter the Lyt-2+3+ cell subset in either strain. Thus, both doses of Ta-1 modulated Lyt-1+/2+3+ ratios, with each dose affecting a different T-cell subset. The changes in the response to thyroglobulin are apparently exerted through the regulation of the functional T-cell subset balance.
OSF-distributed computing environment for multimedia telemedicine services in global PACS

In this paper, we present our approach to developing global picture archiving and communication system (PACS) remote consultation and diagnosis (RCD) application using the Open Software Foundation (OSF) Distributed Computing Environment (DCE) services and toolkits. The current RCD system now uses programming services similar to those offered by OSF DCE, the Cell Directory Service, the Distributed Time Service, the Security Service, the RPC Facility, and the Threads Facility. In this research we have formally applied OSF DCE services to the Global PACS RCD software. The use of OSF DCE services for Global PACS enables us to develop a robust distributed structure and new user services which feature reliability and scalability for Global PACS environments.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Expression of Transforming Growth Factor-α in Mid-gestation Human Fetal Lung

Transforming growth factor-α (TGF-α), a member of the epidermal growth factor (EGF) family, is a potent mitogen for several cell types. To investigate the possible role of TGF-α in the development of midgestation human fetal lung, we studied its distribution with immunohistochemistry and determined levels of steady-state TGF-α mRNA by Northern analysis of cellular RNA isolates from lung. Lung was obtained from fetuses at 10 to 22 wk of gestation (n = 14) and immunostained for TGF-α. TGF-α was localized in epithelial cells at all gestational ages examined. Immunostaining was particularly prominent in bronchiolar epithelial cells. TGF-α immunoreactivity was also associated with arterial smooth muscle cells, as well as with nerves. Occasional chondrocytes were also associated with TGF-α immunoreactivity. Total cellular RNA was isolated from lung tissue obtained from additional fetuses at gestational ages 10 to 24 wk (n = 22). TGF-α mRNA was present in RNA extracts of all fetal lungs studied. We conclude that...
Molt cycle alterations in behavior, feeding and diel rhythms of a decapod crustacean, the spiny lobster Panulirus argus

The crustacean molt cycle manifests extensive behavioral changes in addition to physiological and integumentary modifications. The paucity of quantitative studies led us to characterize molt stage dependent alterations in rhythmic locomotor, feeding, and agonistic behavior of subadult spiny lobster Panulirus argus held grouped and solitarily in simulated natural conditions. Non-disruptively determined molt stages were defined as proportions of intermolt duration. Significant nocturnal rhythmicity persisted through the full molt cycle, though daily form varied as a function of activity level and molt stage. A distinct early evening peak signaled initiation of foraging and walking behavior. Thereafter, rhythm amplitude either declined progressively (low activity: unimodal pattern), remained high (high activity: nocturnal plateau), or exhibited a secondary early morning peak (intermediate activity: bimodal and polymodal patterns). Activity ceased at or immediately prior to sunrise. Ecdysis was predominantly nocturnal, probably reflecting species specific spatiotemporal movement patterns and social behavior. A selective advantage of nocturnal ecdysis was postulated concerning avoidance of cannibalism and diurnal predators. Locomotor activity and feeding rates were not equivalent through the molt cycle, though both peaked in stages B2-C1. Locomotor activity remained high in metecdysis, decreased sharply at proecdysis initiation (D0), reaching lowest levels in D1-D3, then increased in D3 through B1. Activity dropped steeply at ecdysis, though lobsters were capable of intense and coordinated activity. Feeding decreased slowly through metecdysis after the B2-C1 maximum, then increased temporarily in C4 and D0, indicating heightened feeding motivation. This contrasts with the locomotor activity decrease at proecdysis. Food consumption declined rapidly in D1 and D2 and ceased at the D2-D3 transition. Feeding resumed in B1 or B2, intensifying to maximum in late B2. Feeding remained relatively constant within stages, whereas locomotor activity varied greatly, though both correlated with metabolic needs. Grouped and solitary lobsters displayed similar patterns of foraging and walking, equivalent to those of locomotor activity and feeding of solitary individuals. Frequency of agonistic interactions (not aggression per se) remained relatively constant through the cycle, peaking in metecdysis, though the highest relative proportion occurred near ecdysis. Lobsters then were submissive and avoided physical contact with conspecifics. Clearly, locomotor activity, feeding, and social behavior of P. argus are not simply determined. Indeed, behavior is distinctly phase coordinated with varying metabolic requirements dependent on the proximity to ecdysis and ecological pressures.
Low energy electron microscopy of indium on Si(0 0 1) surfaces

Abstract Low energy electron microscopy is used to study the behavior of thin indium films on Si(0 0 1) surfaces from 100 °C up to 700 °C. For temperatures below 150 °C we see inversions in the LEEM dark-field image and LEED 1/2-order spot intensities as indium coverage increases from 0 to 2 ML. For temperatures between 150 and 600 °C we find the formation of a disordered and an ordered (4 × 3) indium phase on the surface. For temperatures above 500 °C we observe significant rearrangement of the Si(0 0 1) surface due to the presence of indium and etching of the Si(0 0 1) surface by indium at temperatures greater than 650 °C.
Synergid Cell Death in Arabidopsis Is Triggered following Direct Interaction with the Pollen Tube

During angiosperm reproduction, one of the two synergid cells within the female gametophyte undergoes cell death prior to fertilization. The pollen tube enters the female gametophyte by growing into the synergid cell that undergoes cell death and releases its two sperm cells within the degenerating synergid cytoplasm to effect double fertilization. In Arabidopsis (Arabidopsis thaliana) and many other species, synergid cell death is dependent upon pollination. However, the mechanism by which the pollen tube causes synergid cell death is not understood. As a first step toward understanding this mechanism, we defined the temporal relationship between pollen tube arrival at the female gametophyte and synergid cell death in Arabidopsis. Using confocal laser scanning microscopy, light microscopy, transmission electron microscopy, and real-time observation of these two events in vitro, we demonstrate that synergid cell death initiates after the pollen tube arrives at the female gametophyte but before pollen tube discharge. Our results support a model in which a signaling cascade triggered by pollen tube-synergid cell contact induces synergid cell death in Arabidopsis.
Wave-kinetic method, phase-space path integrals, and stochastic wave propagation

A phase-space path-integral approach to random wave propagation is introduced as a natural extension of the wave-kinetic method. By virtue of its relationship to the Wigner distribution function, the latter is limited to the computation of second-order statistical moments associated with a nonlocal, complex, stochastic, Schrodinger-like equation. The phase-space path approach, on the other hand, permits the asymptotic evaluation of second- and higher-order statistical observables in a manner analogous to that followed in the recently formulated configuration-space path-integral approaches to the conventional local, complex, stochastic, parabolic equation.
PerturbativeO(αs2)corrections to the hadronic cross section near heavy quark-antiquark thresholds ine+e−annihilation

It is demonstrated how perturbative O({alpha}{sub s}{sup 2}) relativistic corrections to the nonrelativistic stable heavy quark-antiquark production cross section in e{sup +}e{sup {minus}} annihilation based on a Coulombic QCD potential can be systematically calculated using the concept of effective field theories. The O({alpha}{sub s}{sup 2}) corrections from the relativistic energy-momentum relation, the relativistic phase space corrections and the O({alpha}{sub s}{sup 2}) corrections involving the group theoretical factors C{sub F}{sup 2} and C{sub F}T are determined explicitly. For the case of t{bar t} production the sum of these corrections amounts to 3{percent}{endash}7{percent} over the whole threshold regime and is insensitive to variations in the top width. Perturbative O({alpha}{sub s}{sup 2}) corrections to the leptonic decay width of heavy quark-antiquark {sup 3}S{sub 1} vector resonances are extracted. {copyright} {ital 1997} {ital The American Physical Society}
Increased transcellular permeability of rat small intestine after thermal injury

The pathway which results in a loss of intestinal barrier function and transepithelial transfer of macromolecules after cutaneous thermal injury is unknown. To determine the enhanced absorption pathway, transepithelial transport of horseradish peroxidase (HRP) was examined ultrastructurally after a thermal injury. Within 6 h after the injury, increased HRP uptake was seen in the portal and systemic blood with the maximal increase in uptake measured at 18 h postinjury; permeability returned to normal by 72 h postinjury. Morphologically, the increased uptake was found to be transcellular through ultrastructurally normal intestinal absorptive cells. Occasional focal regions of enhanced HRP uptake were found and this enhanced uptake was attributed to focal intestinal epithelial disruptions. This increase in intestinal permeability represents a transient loss of intestinal barrier function and potentially allows absorption of macromolecules such as endotoxin from the intestinal lumen into the portal circulation early after thermal injury.
Incapacitation and Just Deserts as Motives for Punishment

What motivates a person's desire to punish actors who commit intentional, counternormative harms? Two possible answers are a just deserts motive or a desire to incarcerate the actor so that he cannot be a further danger to society. Research participants in two experiments assigned punishments to actors whose offenses were varied with respect to the moral seriousness of the offense and the likelihood that the perpetrator would commit similar future offenses. Respondents increased the punishment as the seriousness of the offense increased, but their sentences were not affected by variations in the likelihood of committing future offenses, suggesting that just deserts was the primary sentencing motive. Only in a case in which a brain tumor was identified as the cause of an actor's violent action, a case that does not fit the standard prototype of a crime intentionally committed, did respondents show a desire to incarcerate the actor in order to prevent future harms rather than assigning a just deserts based punishment.
Protecting convolution-type aritmetic array calculations with generalized cyclic codes

Fault-tolerance in dense high-speed arithmetic units that calculate convolutions between arrays of data is introduced through cyclic codes which are defined over the rings and fields commonly employed by such units. New systematic encoding and data manipulation techniques make the application of these generalized cyclic codes to error detection straightforward and efficient. The necessary overhead parity computations have complexity proportional to the number of parity symbols squared, whereas the error-detecting capability for both random and burst errors is directly related to this parity number.
Influence of Bolt Joint on Dynamic Characteristic of Linear Rolling Guide

Bolt joint has an important influence on the dynamic characteristic of guide rail. Linear rolling guide is chosen as the research object in this paper. Firstly, the dynamic model of the linear rolling guide joint surface is established and its natural frequency is figured out. Then we use ANSYS to make finite element analysis of guide on whether the bolt joint is considered or not. Finally, the validity of finite element model is verified through modal test. By comparing the results of the two kinds of finite element analysis with the theoretical result, we can conclude that the finite element model considering the bolts joint is closer to the theoretical result. So the bolt joint has a great influence on the dynamic characteristics of linear rolling guide. This paper provides the theoretical guide for the research on the bolt joint.
The State of Consciousness in Focal Motor Convulsions

SUMMARY Although patients with convulsive movements of both sides of the body usually have marked impairment of consciousness, such attacks may occur with normal awareness. A case is briefly reported. The physiological mechanisms which may be involved are discussed. The mode of impairment of consciousness in focal motor convulsions is discussed. RESUME Bien que des malades souffrant de mouvements convulsifs aux deux cotes du corps manifestent generalement un endommagement marque de la conscience, des attaques de ce genre peuvent se produire lors d'un etat normal de la conscience. Breve communication d'un cas de ce genre. Discussion des mecanismes physiologiques susceptibles d'etre impliques. Discussion du genre de l'obscurcissement de la conscience lors de convulsions motrices focales.
Carbon dioxide consumption during soil development

Carbon is sequestered in soils by accumulation of recalcitrant organic matter and by bicarbontate weathering of silicate minerals.
Periodate increases the sensitivity of sarcoplasmic reticulum to phospholipase A2

Sodium meta periodate produced two types of effects on the uptake of Ca2+ by fragmented sarcoplasmic reticulum from rabbit skeletal muscle. Treatment of the sarcoplasmic reticulum for 10 min with 2mM periodate at pH 5.5 resulted in a marked decrease in the ability of the sarcoplasmic reticulum to accumulate Ca2+. The decreased Ca2+ accumulation cannot be attributed to an inhibition of the sarcoplasmic reticulum (Ca2+Mg2+)-ATPase. Pretreatment of sarcoplasmic reticulum for 10 min with 0.5 mM periodate at pH 6.1 by itself had little or no effect on Ca2+ uptake, but this periodate pretreatment caused the Ca2+ accumulation to be more sensitive to inactivation by phospholipase A2. It is proposed that some types of muscular dystrophy may result from a mutation that has little effect on sarcoplasmic reticulum activity but predisposes it to abnormal inactivation by degradative enzymes.
The conjugate gradient method solves the neutron transport equation h‐optimally

We report a serendipitous finding that the conjugate gradient method is able to obtain the solution to the linear system derived by the discontinuous Galerkin method for the discrete-ordinate approximation of the mono-energetic time-independent neutron transport equation to a specified accuracy in a number of iterations which is bounded independently of the order of the system. A theoretical explanation for this phenomenon is given. The results of an experiment to test the theory are presented. Copyright © 2007 John Wiley & Sons, Ltd.
Phospholipase Cδ1 Is a Guanine Nucleotide Exchanging Factor for Transglutaminase II (Gαh) and Promotes α1B-Adrenoreceptor-mediated GTP Binding and Intracellular Calcium Release

Effectors involved in G protein-coupled receptor signaling modulate activity of GTPases through GTPase-activating protein or guanine nucleotide exchanging factor (GEF). Phospholipase Cdelta1 (PLCdelta1) is an effector in tissue transglutaminase (TGII)-mediated alpha1B-adrenoreceptor (alpha(1B)AR) signaling. We investigated whether PLCdelta1 modulates TGII activity. PLCdelta1 stimulated GDP release from TGII in a concentration-dependent manner, resulting in an increase in GTPgammaS binding to TGII. PLCdelta1 also inhibited GTP hydrolysis by TGII that was independent from the alpha(1B)AR. These results indicate that PLCdelta1 is GEF for TGII and stabilizes the GTP.TGII complex. When GEF function of PLCdelta1 was compared with that of the alpha(1B)AR, the alpha(1B)AR-mediated GTPgammaS binding to TGII was greater than PLCdelta1-mediated binding and was accelerated in the presence of PLCdelta1. Thus, the alpha(1B)AR is the prime GEF for TGII, and GEF activity of PLCdelta1 promotes coupling efficacy of this signaling system. Overexpression of TGII and its mutants with and without PLCdelta1 resulted in an increase in alpha(1B)AR-stimulated Ca2+ release from intracellular stores in a TGII-specific manner. We conclude that PLCdelta1 assists the alpha(1B)AR function through its GEF action and is primarily activated by the coupling of TGII to the cognate receptors.
Effect of Gold Nanoparticles on Photoexcited Charge Carriers in Powdered TiO2−Long Range Quenching of Photoluminescence

Photoluminescence spectroscopy was employed to study the photoinduced charge transfer between TiO2 nanoparticles and Au nanoparticles under vacuum. We found that small coverages of 3 nm Au nanoparticles deposited on TiO2 significantly diminish the 540 nm (2.3 eV) photoluminescence emission from TiO2 because of the redistribution of the photoexcited charge to Au nanoparticles that are capable of accepting negative charges behind the Schottky barrier. The lack of development of the photoluminescence emission of Au/TiO2 during continuous UV irradiation occurs because of a short circuit established through Au nanoparticles in which transferred electrons in Au recombine nonradiatively with holes in TiO2. The photoexcited electron transfer from TiO2 to the Au nanoparticles occurs beyond the Au particle perimeter over a distance of at least 4 nm. The quenching of photoluminescence by resonance energy transfer from TiO2 to Au nanoparticles is unimportant as Au plasmonic absorption is not observed.
Anisotropy of magnetic susceptibility variations in a single icelandic columnar basalt

Abstract Measurements of the anosotropy of magnetic susceptibility in 34 specimens drilled from a single Icelandic columnar basalt segment reveal a preferred, long-axis alignment of magnetic minerals normal to the long axis of the column and well grouped. Maximum elongation of these minerals occurs in regions which crystallized late, as independently indicated by relative samarium concentrations. We propose that the variations in magnetic mineral elongation are controlled by variations in thermal stress in the cooling column, before complete solidification. An upper limit of 75–100 bars is suggested for these stresses.
The Classification of Linearly Polarized Transverse Electric Waves

Abstract Recently the author has undertaken the classification of continuous solutions to some common vector PDEs. These include the simplest of Beltrami solutions to hydrodynamic flows and electromagnetic wave equations (which are, in fact, closely related). In this paper, we consider linearly polarized transverse electric wave solutions to the electromagnetic wave equation: ∇ × E = i ω H ; ∇ × H =− i ω E . Using Clebsch functions and differential geometric techniques the author is able to give a discussion of the most general possible forms of propagation of linearly polarized waves. A zero curvature condition (which asserts that the Clebsch functions necessary to represent the solutions are expressible in terms of Cartesian variables) reduces the study of vector PDEs to nonlinear PDEs, which may be solved in special cases. The benefit is that the Clebsch representation is the one that is the most useful for analyzing the structure of the flow. This method of analysis is now a feasible solution method due to the tremendous advances in mathematical software allowing one to compute curvatures, given metric functions. For the special case of linearly polarized transverse electric waves the analysis may be applied to a great extent.
Are we altering the natural history of primary myelofibrosis

Primary myelofibrosis (PMF) is a clonal hematologic malignancy with a variable disease course; survival ranges from months to years. Historically, only allogeneic hematopoietic stem cell transplantation (alloHSCT) has demonstrated an ability to alter the natural history of PMF, but high treatment-related mortality risks limit the utility of alloHSCT to a minority of patients with PMF or myelofibrosis secondary to other myeloproliferative neoplasms. The recent development of therapies that regulate the Janus kinase-signal transducer and activator of transcription signaling pathway has changed the treatment landscape from primarily palliative treatment to potential disease modification.
Theoretical spectrosccopy of semiconductor clusters

ABSTRACT The blue shift of the absorption spectrum of CdS clusters is calculated using pseu-dopotentials. The calculated blue shift is in exceptionally good agreement with ex-periment over a wide range of cluster sizes. 1. INTRODUCTION Advances in Inorganic Chemistry in recent years have made it possible to synthesizesemiconductor clusters with well defined cluster sizes and crystal structures.1'2 At thesame time, experimental investigations of these clusters have revealed the effect of size on their optical and chemical properties.17 The main finding of these studies is that the absorption spectrum shifts to higher energies (blue shift) with decreasingcluster size. Simple effective mass models (EMM) have been employed to explain thisphenomenon, but the agreement with experiment has only been qualitative."3 Weinvestigated this problem by carrying out band structure calculations and obtained quantitative agreement with experiment. This paper presents the results of these calculations.
Effect of simulated acid rain on reproductive attributes of red spruce (Picea rubens sarg.)

Abstract Red spruce ( Picea rubens Sarg.) growth and reproduction is declining in many areas of the eastern United States ( Klein and Perkins , Bot. Rev. 54 , 1–43, 1988). An often cited cause of this decline is air pollution. In this study simulated acid rain was used to examine the effects of low pH on the female reproductive structures of five red spruce trees showing no signs of pollution damage. Cone scale weight, seed weight, number of seeds per cone, and per cent germination of filled seed did not differ significantly among the acid rain treatments. The percentage of filled seed per cone was significantly reduced as the pH of the simulated rain solutions declined.
Circulation anomaly mechanisms in the tropical Atlantic sector during the northeast Brazil rainy season - Results from the GISS general circulation model

The role of the sea surface temperature (SST) pattern in the tropical Atlantic on the overlying atmosphere is studied from a 7-year run of the general circulation model (GCM) of the Goddard Institute for Space Studies (GISS) (period 1980–1986) and in comparison to upper air analyses of the European Centre for Medium-Range Weather Forecasts (ECMWF), surface ship observations of the SST and wind fields (COADS), and rainfall measurements in Northeast Brazil (Nordeste). Observations for March to April show that reduced northward SST decrease in the tropical Atlantic is accompanied by reduced northward decrease of lower-tropospheric thickness, which accounts for an inverse change in the meridional pressure gradient and reduced northerly wind component; this in turn entails a northward displaced Intertropical Convergence Zone and drought in the Nordeste. The GCM simulation reproduces the thermal and hydrostatic forcing of SST on the meridional gradients of lower-tropospheric thickness and pressure in the proper sense, albeit more weakly than observed. The modeled meridional wind component follows the meridional pressure gradient in the proper sense, but mean and range are smaller than observed, and the modeled interannual variability is not altogether consistent with observational evidence. The modeled March to April precipitation in the Nordeste shows little relation to the observed rainfall, although it is weakly related with the observed interhemispheric SST contrast and with the modeled near-surface meridional wind component. Both modeled and observed March to April Nordeste rainfall are negatively related with SST anomalies in the equatorial Pacific in March to April as well as in the immediately preceding January. Both in January and in March to April the modeled soil moisture exhibits a strong dependence on the modeled precipitation, but neither resembles in interannual variability nor in absolute amounts of the observed rainfall. Overall the GISS GCM seems to reproduce reasonably well the response of lower-tropospheric thickness and near-surface pressure to SST, while the simulation of wind and rainfall is somewhat deficient.
The synthesis of proteolipid protein by isolated rat liver mitochondria.

Abstract About 15% of the total (3H)leucine incorporated into protein by isolated rat liver mitochondria in vitro could be extracted by chloroform:methanol. This incorporation was inhibited by chloramphenicol and carbomycin, both specific inhibitors of mitochondrial protein synthesis. SDS-gel electrophoresis of the mitochondrial membrane revealed 6–7 labeled bands. Label in the proteolipid fraction was present mainly in a band of 40,000 molecular weight. Several labeled bands observed in gels of the mitochondrial membrane were not removed or changed by extraction with chloroform:methanol suggesting that some, but not all, of the proteins synthesized by rat liver mitochondria are proteolipids.
Total syntheses of arylindolizidine alkaloids (+)-ipalbidine and (+)-antofine

This paper presents the first application of two recently developed reactions to natural product synthesis. The first method involves a 6-endo-trig cyclization to prepare a versatile chiral enaminone building block. The second is a direct C-H arylation reaction. As a showcase for the utility of these methods, (+)-antofine and (+)-ipalbidine were synthesized in only 8 steps and 24-26% overall yields.
Valve repair improves the outcome of surgery for mitral regurgitation: A multivariate analysis

Background Mitral valve repair has been suggested as providing a better postoperative outcome than valve replacement for mitral regurgitation, but this impression has been obscured by differences in baseline characteristics and has not been confirmed in multivariate analyses. Methods and Results The outcomes in 195 patients with valve repair and 214 with replacement for organic mitral regurgitation were compared using multivariate analysis. All patients had preoperative echocardiographic assessment of left ventricular function. Before surgery, patients with valve repair were less symptomatic than those with replacement (42% in New York Heart Association functional class I or II versus 24%, respectively; P=.001), had less atrial fibrillation (41% versus 53%; P=.017), and had a better ejection fraction (63±9% versus 60±12%, P=.016). After valve repair, compared with valve replacement, overall survival at 10 years was 68±6% versus 52±4% (P=.0004), overall operative mortality was 2.6% versus 10.3% (P=.002), o...
Thermally induced conformational changes in poly(vinyl chloride)

Fourier transform infrared spectroscopy has been used for the detection of thermally induced conformational changes in atactic poly(vinyl chloride) (PVC). Difference spectra emphasize changes in the distribution of gauche defects in the chains as functions of temperature and annealing. Specific bands in the ν(CCl) and δ(CH2) regions varied with inverse temperature, allowing a calculation of the activation energies of the rotamer species. Conformational changes were also detected in quenched PVC films as a result of annealing below the glass transition temperature, Tg.
THE ROLE OF BODY SIZE, PHYLOGENY, AND AMBIENT NOISE IN THE EVOLUTION OF BIRD SONG

Morton found that the average emphasized frequency in the songs of tropical bird species in low-forest habitats was lower than that of species in grassland or edge habitats. He suggested that this was due to a frequency window around 1585-2500 Hz in low-forest habitats, and that there was selection to produce songs with frequencies in this window in order to increase the transmission distance of the songs. In the present study, we analyze the constraints of body size and evolutionary history on the ability of avian species to respond to this selection. Also, we examine the spectral distribution of ambient noise as an additional selective factor. There is a correlation between body size and the emphasized frequency of the song for the species analyzed by Morton. Larger birds produce songs with lower emphasized frequencies. Morton's demonstration that birds in the low forest produce songs with lower frequencies is confounded by the fact that larger birds also live in this habitat. Phylogeny is also a potent...
Buckling behaviors of open-tip carbon nanocones at elevated temperatures

This paper used molecular dynamics simulations to investigate buckling behaviors of open-tip carbon nanocones (CNCs) at elevated temperatures ranging from 300 to 700 K. Influences of cone height and apex angle on the buckling behaviors were examined. Some interesting findings, especially on the change in buckling mode shapes of the CNCs, were observed in the study. For the CNCs having an apex angle of 19.2°, the one with a lower cone height exhibited a shrinking/swelling buckling mode shape even at the higher temperature 700 K. However, as the cone height increased, the CNC displayed a deflective buckling mode shape at 300 K, but changed to a shrinking/swelling buckling mode shape when the temperature grew to 500 K. Regarding the influences of apex angle, the CNCs presented a deflective buckling mode shape even at 700 K as the apex angle expanded. This is opposite to the shrinking/swelling buckling mode shape of the CNC having the smallest apex angle of 19.2°.
An analysis of letter expertise in a levels-of-categorization framework

While there has been increasing effort in dissociating the neural substrates recruited by perception of different objects, the theoretical and behavioural work needed to understand such dissociation lags behind. In an attempt to compare expertise in letter and face perception, we outline a theoretical framework that characterizes different types of object expertise based on the task demand (level of abstraction) required in object categorization. Face perception requires categorization at a subordinate level, whereas letter perception involves mainly basic-level categorization. Accordingly face and letter perception should represent two different types of expertise and display different neural and behavioural markers. Results from three behavioural experiments supported the predictions of the framework in that letter expertise is characterized by an enhancement of the basic-level advantage, instead of its attenuation as typically found for face perception. We compare this framework with Farah's taxonomy o...
Glutamic dehydrogenase from rat heart mitochondria. II. Kinetic characteristics

Glutamic dehydrogenase purified from rat heart mitochondria has been characterized with regard to its substrate kinetics and the influence of nucleotides and potassium phosphate on its kinetic properties. The enzyme had characteristics similar to liver mitochondrial glutamic dehydrogenase. These included several double reciprocal plots which were biphasic, indicating homotropic interaction; inhibition by GTP, which was overcome by ADP and phosphate; and activity with both NAD(H) and NADP(H). There were a number of significant differences however, in the specific kinetic properties of heart mitochondrial glutamic dehydrogenase. The Vmax of reductive amination was four-fold greater with NADH than with NADPH. The maximum rate of oxidative deamination was ten-fold greater with NAD compared to NADP. The differences also included: saturating levels of NADH and NADPH were stimulatory rather than inhibitory; ammonia was stimulatory at millimolar levels; NADP and alpha-ketoglutarate were both inhibitory at saturating levels; and ADP increased reductive amination 30% at lower levels of NADH but inhibited at higher (stimulatory) levels of NADH.
Experimental and Numerical Studies of Ethanol Decomposition Reactions

Ethanol pyrolysis experiments at 1.7−3.0 atm and 1045−1080 K were performed in the presence of radical trappers using a variable pressure flow reactor. Stable species time histories were determined using continuous sampling, on-line Fourier transform infrared spectrometry, and off-line gas chromatography. The rate constant k1 of the molecular decomposition reaction, C2H5OH → C2H4 + H2O (R1), was determined experimentally. The obtained result agrees very well with extrapolation of the recent shock-tube data of Herzler et al.1 The multichannel unimolecular decomposition of ethanol was also investigated theoretically on the basis of RRKM/master equation calculations. The effects of the hindered rotations in C2H5OH and quantum tunneling on the molecular decomposition reaction were taken into account. The reaction R1 was found to be strongly dependent on temperature and the dominant channel over the range of temperatures 300−2500 K at 1 atm. The calculated k1 is in excellent agreement with the recent theoretic...
Attributions for Inconsistencies Between Online and Offline Self-Presentations

This study investigated how people make sense of self-portrayals in social media that are inconsistent with impressions formed through other interpersonal interactions. The research focused on how inconsistent online information affects interpersonal impressions and how motivation to manage impressions influences the types of attributions that actors and observers make for the misleading online behavior. Results show that the relationship between observer and the target influences evaluations of online/offline inconsistencies: Subjects rated the inconsistencies of acquaintances as more intentionally misleading, more hypocritical, and less trustworthy relative to the inconsistencies of friends. In addition, the types of attributions people made for online behavior depended on the perspective of the person providing the explanation: People explained their own online behavior more favorably than the online behavior of both friends and acquaintances.
Age- and Ethnic-Specific Elevation of ALT Among Obese Children at Risk for Nonalcoholic Steatohepatitis (NASH): Implications for Screening

The objectives are to: (1) characterize ethnic-specific differences in alanine aminotransferase (ALT) elevation among obese children, (2) investigate the earliest ages at which significant ALT elevation occurs, and (3) determine associations between ALT and biochemical parameters. A cohort of 134 multiethnic obese children and adolescents was analyzed retrospectively. ALT levels > or =45 U/L or or = 45 U/L (49.4%, vs 37.9% for girls, P = .002); 17.5% were Hispanic boys less than 7 years old. Obese Hispanic children, particularly boys, not only have higher ALT levels but present alarmingly young with high-risk levels. This study highlights a discrete subgroup of children who may present with fatty liver at a younger age and should be screened earlier.
Numerical solution of Space Shuttle Orbiter flowfield including real-gas effects

The hypersonic, laminar flow around the Space Shuttle Orbiter has been computed for both an ideal gas (gamma = 1.2) and equilibrium air using a real-gas, parabolized Navier-Stokes code. This code employs a generalized coordinate transformation; hence, it places no restrictions on the orientation of the solution surfaces. The initial solution in the nose region was computed using a 3-D, real-gas, time-dependent Navier-Stokes code. The thermodynamic and transport properties of equilibrium air were obtained from either approximate curve fits or a table look-up procedure. Numerical results are presented for flight conditions corresponding to the STS-3 trajectory. The computed surface pressures and convective heating rates are compared with data from the STS-3 flight.
Detection of phase in modulated optical signals subject to ideal Rayleigh fading

Techniques are developed to analyze the mean-squared phase error (MSPE) on modulated laser signals subject to ideal Rayleigh fading. The mean-squared error in the return signals of laser radars based on sinusoidal intensity modulation is analyzed. Maximum-likelihood phase detection is assumed. Exact formulas are derived for the MSPE incurred in working with deterministic signals as well as signals subject to ideal Rayleigh fading. The benefits of filtering phase data on the basis of amplitude thresholding are quantified. The formulas developed are valid in the case of low as well as high signal-to-noise ratios.
Diffusion of calcium in calcium tungstate single crystals

Abstract The self-diffusion of Ca in single crystal CaWO4 doped with Nd and Na has been measured in the temperature range 0.53 Tm−0.9 Tm. From 0.75 Tm−0.9 Tm. D = (4.0 ± 0.3) × 10 −3 exp (− 55,800 ± 620 RT ) cm 2 sec −1 and from 0.53 to 0.75 Tm, D = (1.9 ± 0.4) × 10 −8 exp (− 22,900 ± 1100 RT ) cm 2 sec −1 . In the range 0.75 Tm−0.9 Tm, diffusion appears to be intrinsic lattice diffusion, via a vacancy mechanism. In CaWO4 the predominant intrinsic defect structure appears to be the Schottky defect with vacancies on the Ca2+ and O2− sites. The energy of formation of Schottky defect pairs is estimated to be 52 to 66 kcal/g.mole. In the temperature range 0.53 Tm−0.75Tm, Ca diffusion in CaWO4 appears to be extrinsic. Diffusion profiles for samples annealed at lower temperatures lead to two values of D: (i) a small D near the crystal surface (within 20–30 μ), believed to be bulk extrinsic diffusion, and (ii) a large D deep within the crystal, which probably results from superposition on extrinsic bulk diffusion of contributions from diffusion down the dislocations.
(Mis)Managing Diversity: Worker Rights and US Trade Policy

The metaphor of the two-level game has been used to describe the process whereby political leaders find themselves negotiating simultaneously at the domestic and international tables when trying to reach international cooperative agreements. This article examines the role of domestic politics in the US debate over trade policy in recent years. Specifically, the article analyzes the bargaining between the Clinton administration and the US Congress over the appropriate role for labor (and environmental) issues in trade negotiations in the context of the debate over so-called "fast-track" negotiating authority. The article then goes on to analyze how the domestic politics of this issue could affect an international negotiation over worker rights in the World Trade Organization.
Inadequate protein intake and hormonal secretion.

The effect on hormonal secretion of a corn diet both quantitatively and qualitatively deficient in protein was investigated in six normal male subjects. Total caloric intake was adequate at 2400 calories per day. Growth hormone responses to arginine were depressed in each subject after only a 25 to 26 day period of this restricted protein intake. Basal insulin secretion and secretion of insulin after glucose and arginine were unaltered.
Corticosterone levels predict survival probabilities of Galápagos marine iguanas during El Niño events

Plasma levels of corticosterone are often used as a measure of “stress” in wild animal populations. However, we lack conclusive evidence that different stress levels reflect different survival probabilities between populations. Galapagos marine iguanas offer an ideal test case because island populations are affected differently by recurring El Nino famine events, and population-level survival can be quantified by counting iguanas locally. We surveyed corticosterone levels in six populations during the 1998 El Nino famine and the 1999 La Nina feast period. Iguanas had higher baseline and handling stress-induced corticosterone concentrations during famine than feast conditions. Corticosterone levels differed between islands and predicted survival through an El Nino period. However, among individuals, baseline corticosterone was only elevated when body condition dropped below a critical threshold. Thus, the population-level corticosterone response was variable but nevertheless predicted overall population health. Our results lend support to the use of corticosterone as a rapid quantitative predictor of survival in wild animal populations.
Glial cell development in the Drosophila embryo.

Summary Glial cells play a central role in the development and function of complex nervous systems. Drosophila is an excellent model organism for the study of mechanisms underlying neural development, and recent attention has been focused on the differentiation and function of glial cells. We now have a nearly complete description of glial cell organization in the embryo, which enables a systematic genetic analysis of glial cell development. Most glia arise from neural stem cells that originate in the neurogenic ectoderm. The bifurcation of glial and neuronal fates is under the control of the glial promoting factor glial cells missing. Differentiation is propagated through the regulation of several transcription factors. Genes have been discovered affecting the terminal differentiation of glia, including the promotion glial‐neuronal interactions and the formation of the blood‐nerve barrier. Other roles of glia are being explored, including their requirement for axon guidance, neuronal survival, and signaling. BioEssays 23:877‐887, 2001. fl 2001 John Wiley & Sons, Inc.
Computing the error linear complexity spectrum of a binary sequence of period 2/sup n/

Binary sequences with high linear complexity are of interest in cryptography. The linear complexity should remain high even when a small number of changes are made to the sequence. The error linear complexity spectrum of a sequence reveals how the linear complexity of the sequence varies as an increasing number of the bits of the sequence are changed. We present an algorithm which computes the error linear complexity for binary sequences of period /spl lscr/=2/sup n/ using O(/spl lscr/(log/spl lscr/)/sup 2/) bit operations. The algorithm generalizes both the Games-Chan (1983) and Stamp-Martin (1993) algorithms, which compute the linear complexity and the k-error linear complexity of a binary sequence of period /spl lscr/=2/sup n/, respectively. We also discuss an application of an extension of our algorithm to decoding a class of linear subcodes of Reed-Muller codes.
Assessment and prediction of natural hazards from satellite imagery

Since 2000, there have been a number of spaceborne satellites that have changed the way we assess and predict natural hazards. These satellites are able to quantify physical geographic phenomena associated with the movements of the earth's surface (earthquakes, mass movements), water (fl oods, tsunamis, storms), and fi re (wildfi res). Most of these satellites contain active or passive sensors that can be utilized by the scientifi c community for the remote sensing of natural hazards over a number of spatial and temporal scales. The most useful satellite imagery for the assessment of earthquake damage comes from high-resolution (0.6 m to 1 m pixel size) passive sensors and moderate resolution active sensors that can quantify the vertical and horizontal movement of the earth's surface. High-resolution passive sensors have been used successfully to assess fl ood damage while predictive maps of flvulnerability areas are possible based on physical variables collected from passive and active sensors. Recent moderate resolution sensors are able to provide near real-time data on fiand provide quantitative data used in fibehavior models. Limitations currently exist due to atmospheric interference, pixel resolution, and revisit times. However, a number of new microsatellites and constellations of satellites will be launched in the next fi ve years that contain increased resolution (0.5 m to 1 m pixel resolution for active sensors) and revisit times (daily < 2.5 m resolution images from passive sensors) that will signifi cantly improve our ability to assess and predict natural hazards from space.
Metaphors for Industrial Rationality: The Social Construction of Electronics Policy in the United States and France

For a generation social scientists have located culture outside the boundaries of rationalized institutions.
Simulation Modeling and Performance Evaluation of Multiple Access Protocols

This paper presents an object-oriented simulation model that can be used to evaluate the perfor mance of MAC (Multiple ACcess) protocols. It is intended for satellite communication networks in which the propagation delay plays a major role on the performance of the communication channel. The model has been used to evaluate the perfor mance of multiple access protocols for NASA's Mars Regional Network in the Martian environ ment with some specific requirements. These re quirements include protocol robustness, stringent use of power and buffer memory, channel stabil ity, and low complexity of the control algorithm. The simulation model can accommodate different classes of MAC protocols including fixed assign ments, demand assignments, random access, hy brid of random access, and adaptive protocols. While the simulation model has been developed to evaluate the MAC protocols for the Martian envi ronment, it is intended to accommodate other multiple access protocols with different require ments.