cssi/SciSciGPT-SciSciNet huggingface dataset:
Application of neural network technique in implementation of constant weight codes

Constant weight codes are very useful in high speed optical data links and spread spectrum systems. The error correction/detection depends on the length of the code (amount of redundancy added) and minimum distance of the code. The current technique, utilizing lookup tables for error correction/detection, is a problem as far as high throughput is concerned. A scheme utilizing a neural network approach is proposed. It results in better error correction and retransmission capability than does the current technique and can be used efficiently in frequency hopped systems. The neural network approach is much faster, and the decoding process has been reduced to simple vector-matrix multiplication. >
ALLELIC VARIATION AT THE LEVEL OF INTRAGENIC RECOMBINATION

This report examines five different naturally occurring alcohol dehydrogenase-1 alleles via the recombinational behavior of Adh1(-) mutants induced within them. Twenty-two biochemically characterized Adh1(-) mutants have been assessed for ability to recombine intragenically, using data generated by specifically staining for the presence of ADH in pollen grains. Each of the five naturally occurring Adh1 progenitor isoalleles appears unique. Allelic variation exists in (1) the rate of intragenic recombination sustained by an allele, and (2) the pattern of recombinational success or failure based on the ancestry of each mutant in a heteroallelic pair. In other words, we find quantitative and qualitative Adh1 allelic variation at the level of intragenic recombination. I have experimentally excluded several explanations for recombinational restriction. These results will be related to the structure, function and naturally occurring variability of the gene in higher organisms. Specifically, the "recon" (unit of recombination) has been resurrected as a potentially useful unit of natural selection. The reasonableness of several genres of hypotheses in evolutionary/population genetics, particularly those involving linkage disequilibrium, is called into question.
Injectable, high‐density collagen gels for annulus fibrosus repair: An in vitro rat tail model

A herniated intervertebral disc often causes back pain when disc tissue is displaced through a damaged annu- lus fibrosus. Currently, the only methods available for annu- lus fibrosus repair involve mechanical closure of defect, which does little to address biological healing in the dam- aged tissue. Collagen hydrogels are injectable and have been used to repair annulus defects in vivo. In this study, high- density collagen hydrogels at 5, 10, and 15 mg/mL were used to repair defects made to intact rat caudal intervertebral discs in vitro. A group of gels at 15 mg/mL were also cross-linked with riboflavin at 0.03 mM, 0.07 mM, or 0.10 mM. These cross-linked, high-density collagen gels maintained their presence in the defect under loading and contributed posi- tively to the mechanical response of damaged discs. Discs exhibited increases to 95% of undamaged effective equilib- rium and instantaneous moduli as well as up to fourfold decreases in effective hydraulic permeability from the dam- aged discs. These data suggest that high-density collagen gels may be effective at restoring mechanical function of injured discs as well as potential vehicles for the delivery of biological agents such as cells or growth factors that may aid in the repair of the annulus fibrosus. V
Effects of pH on Conformational Equilibria of Intrinsically Disordered Proteins

Intrinsically disordered proteins (IDPs) adopt an ensemble of conformations under native physiological conditions. Despite their lack of folded structure, they perform important physiological functions and are predicted to constitute around 30% of the eukaryotic proteome. The success of disorder prediction using a protein's primary structure suggests that the propensity for disorder is encoded in the amino acid sequence. Recently, we found that net charge per residue segregates IDP sequences along a globule-to-coil transition, enabling construction of a sequence-space phase diagram that subdivides IDPs based on the polymeric character of their conformational ensembles. Here, we explore the effects of two perturbations that leave sequence composition unchanged: sequence permutation and pH titration. Using atomistic Monte Carlo simulations in ABSINTH implicit solvent, we find that permutants of an arginine-rich IDP sequence exhibit nearly identical polymeric attributes, yet differ in the details of their conformational ensembles. In contrast, fluorescence correlation spectroscopy shows a decrease in translational diffusion times with increasing pH, suggesting that electrostatic and conformational modulation of protonation equilibria is significant even for solvent-exposed titratable groups on flexible protein backbones. The effect is sufficient to induce a collapse transition in a polyarginine polypeptide at a pH well below the pKa of the arginine sidechain. We conclude that the polymeric character of an IDP is largely determined by its sequence composition, but emphasize the importance of accurate constant pH simulation technology in investigating details of its conformational equilibria.Supported by grants 5T32GM008802 from the NIH National Institute of General Medical Sciences and MCB 0718924 from the National Science Foundation.
The sonoluminescence spectrum of seawater

Abstract The sonoluminescence spectra of seawater and of a sodium chloride solution were determined by irradiation with ultrasound at 20 kHz. Ultrasound creates sonoluminescence through the process of acoustic cavitation: the formation, growth and implosive collapse of bubbles in a liquid. The sonoluminescence spectra of both seawater and NaCl in water are characterized by an emission line at 589 nm from excited-state sodium. Excited-state Na atoms are produced from the reaction of Na + with high-energy hydroxyl radicals formed directly during the cavitation event. Emission at 589 nm could be useful in determining whether sonochemical processes associated with cavitation occur in breaking waves or other turbulent flows.
Microsatellite Markers Linked to Stem Rust Resistance Allele Sr9a in Wheat

Host resistance to stem rust of wheat (Triticum aestivum L.), caused by Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. & E. Henn., is more effective and durable when several stem rust resistance (Sr) genes are pyramided into a single line. We studied the Sr9a allele, one of six known alleles at the Sr9 locus on chromosome 2BL, using 116 F 2 plants and their F 2:3 families derived from the cross of near-isogenic lines (NILs) 'Chinese Spring' and ISr9a-Ra. Four microsatellite markers were identified that mapped within 3.6 cM proximal to the Sr9a locus. Fifty: nine wheat accessions were screened with the three codominant and one dominant markers to determine their polymorphism information content (PIC). The marker Xgwm47 revealed 12 alleles and had the highest PIC value of 0.85. We attempted to postulate the presence of Sr9a by phenotypic screening. In accessions that had multiple Sr genes, however, it was not possible to postulate Sr9a due to masking effects. Despite the ambiguity of phenotypic evaluation, Xgwm47 was diagnostic for Sr9a in additional NILs tested. These results suggest that Xgwm47 will be a useful tool for marker-assisted selection of Sr9a in wheat breeding programs.
Sputtered hydrogenated amorphous silicon

Hydrogenated a-Si, whose properties can be modified by impurity doping, can be produced either by decomposition of silane or by reactive sputtering of Si in an argon-hydrogen plasma. This article reviews advances made during the past few years in the preparation and characterization of films produced by the second method. The basic deposition conditions are summarized. The conclusions of analytical studies (photo-emission, infrared spectroscopy, and volumetric measurements of evolved gases), regarding the amount of hydrogen and its bonding configuration in the network, are outlined. The optical, carrier transport, photoconductivity and photoluminescence properties as a function of hydrogen content and doping are described. Electron drift mobilities, deduced from steady state and transient photoconductivity are presented. The transport and recombination properties are discussed with existing models of amorphous semiconductors, and are found to be consistent with atomic relaxations, i.e. polaronic effects.
Scatter band prediction for fracture toughness of specimens with prior load

Abstract This study investigates the warm pre-stress effects under Load–Unload–Cool–Fracture transient with deep-cracked single edge bend specimens of a high strength steel. In the experiment, it has been found that warm pre-stressing increases the apparent overall elastic–plastic fracture toughness KJc_total compared to those of as-received specimens. A simple prediction procedure for fracture toughness of specimens with warm pre-stressing is proposed based on critical plastic zone criterion using fracture parameter superposition rule. It is shown that the increase and the narrower scatter band of fracture toughness of specimens with prior load can be well evaluated within the framework of the Master Curve methodology.
The Blind Men and the Elephant: Selective Examination of the Public-Private Literature Gives Rise to a Faulty Perception

ABSTRACT Wicklund and Gollwitzer make two claims that the distinction between public and private self-awareness/self-consciousness is “Aristotelian,” and that the distinction is fallacious For the distinction to be Aristotelian, as Wicklund and Gollwitzer use that term, requires that the distinction not be embedded in a “process” model of behavior Thus, the first claim is easily shown to be false The second claim rests on a variety of empirical and theoretical issues An examination of these issues reveals (a) that Wicklund and Gollwitzer's alternative interpretations for public self-attention effects are themselves Aristotelian—involving labels but no processes, (b) that their citation of literature relevant to their case is highly selective and misleading, and (c) that their abolition of the public-private distinction would leave an embarrassing contradiction among self-awareness effects, which Wicklund and Gollwitzer apparently are unable to address The vast preponderance of evidence thus supports the utility and the importance of the public-private self-focus distinction
Surface-associated antigens of second, third and fourth stage larvae of Dirofilaria immitis.

Abstract The surface-associated molecules of the second (L2), third (L3) and fourth (L4) larval stages of Dirofilaria immitis were characterized employing radiolabeling techniques and SDS-PAGE analysis. Major labeled components of 35 kDa and 6 kDa were present in extracts from IODO-GEN-labeled L2 and L3 parasites. The results of lactoperoxidase-catalyzed reactions also demonstrated that L2 and L3 stages of D. immitis have a similar repertoire of surface-associated antigens. However, in contrast to the results obtained with IODO-GEN, lactoperoxidase reactions labeled components with apparent molecular weights of 66, 48, 25, 16.5 and 12 kDa. The similarities in the molecular weights of the L2 and L3 surface-associated components and the results of immunoprecipitation experiments which demonstrated that antibodies produced against the 35 kDa molecule from D. immitis L3s also recognize the 35 kDa component from L2 parasites suggest that synthesis of the molecules found at the surface of mature infective larvae begins as early as day 6 of development in the mosquito. D. immitis L4s emerged from the molting process with a repertoire of surface-associated antigens distinct from those found on L2s and L3s. IODO-GEN labeling of D. immitis L4s showed major surface-associated molecules with apparent molecular weights of 57, 40, 25, 12 and 10 kDa when analyzed under non-reducing conditions. In addition to molecules of 57, 40, 25, 12 and 10 kDa, extracts of D. immitis L4s labeled with lactoperoxidase contained additional major bands at 45, 43 and 8 kDa. Metabolic labeling experiments demonstrated a shift in the amount and complexity of the excretory/secretory products released by D. immitis during L3 to L4 development.
Pre-transition phenomena in an iron-nickel alloy

Abstract X-ray diffraction from an Fe-30.5Ni single crystal has been examined to obtain information on the vibrational state of the sample prior to the martensite transformation. The measurements included integrated intensities of Bragg peaks as well as diffuse scattering along several directions in reciprocal space. Data were obtained from room temperature to within approximately 1°K of the transformation temperature. Previous reports of an increase in the mean-square atomic displacements on approaching Ms (determined with Mossbauer techniques) were not confirmed by measurements of the integrated X-ray diffraction peaks. The results of this study reveal a decrease in the mean-squared amplitude of vibration with temperature which is in close agreement with that predicted by harmonic theory. Diffuse X-ray scattering, examined to sample the temperature dependence of particular vibrational modes, gave no indication of softening of short wavelength modes. However, these measurements did reveal a softening of long wavelength (100) [100] modes as the sample approached the Ms temperature. The softening of this mode provides a Bain distortion which can lead to a lattice instability near defects as predicted by localized soft mode theories. Such an instability can be viewed as one mechanism by which a martensite nucleus is formed.
Cholera toxin: Mitogen for Harderian glands of golden hamsters

Abstract 1. Within 2 days, a single injection of 10 μg cholera toxin induces a 6–20-fold increase in mitotic activity in the Harderian glands of male and female golden hamsters. 2. Neither hypophysectomy nor ovarietomy had any influence on this response. 3. The cellular proliferation does not appear to involve cAMP nor is it the result of stress, nor a release from an early mitotic block. 4. Nuclear polyploidy increases within a few hours after treatment. 5. DNA density per unit area increases within 24 hr and is maintained for at least 3 days.
Pulse actinomycin D scheduling in nonmetastatic gestational trophoblastic neoplasia: Cost-effective chemotherapy

The currently accepted method of treatment of patients with nonmetastatic gestational trophoblastic neoplasia (NMGTN) is single-agent chemotherapy. While methotrexate and actinomycin D have shown superiority over other cytotoxic agents, doses of drug and length of treatment are subject to controversy. Recently, the demonstration of the long half-life of actinomycin D in both animal models and humans has necessitated a reevaluation of the method of administration of this drug for NMGTN. Following the demonstration of minimal severe toxicity of pulse actinomyin-D scheduling by E. S. Petrilli and C. P. Morrow (Actinomycin D toxicity in the treatment of trophoblastic disease, Gynecol. Oncol. 9, 18-22 (1980), 12 consecutive patients with nonmetastatic gestational trophoblastic neoplasia were treated. The remission rates, toxicity, and cost effectiveness of pulse actinomycin-D scheduling in these 12 patients are reported.
High heat flux burnout in subcooled flow boiling

The paper reports the results of an experimental research carried out at the Heat Transfer Division of the Energy Department, C.R. Casaccia, on the thermal hydraulic characterization of subcooled flow boiling CHF under typical conditions of thermonuclear fusion reactors, i.e. high liquid velocity and subcooling.
A prospective study of postmenopausal estrogen therapy and subsequent incidence of non-insulin-dependent diabetes mellitus

The potential influence of postmenopausal estrogen therapy on the subsequent development of non-insulin-dependent diabetes mellitus (NIDDM) is relatively unexplored, despite postulated effects of these hormones on glucose tolerance. We examined the association between postmenopausal hormone use and the subsequent incidence of NIDDM in a prospective cohort of 21,028 postmenopausal US women aged 30 to 55 years and free of diagnosed diabetes, cardiovascular disease, and cancer in 1976. During 12 years of follow-up (422,991 person-years), we confirmed 1249 cases of NIDDM. Current users of postmenopausal hormones had a relative risk of NIDDM of 0.80 (95% confidence interval, 0.67 to 0.96) as compared with never users, after adjustment for age and body mass index (BMI). Past users of these hormones had an age- and BMI-adjusted relative risk of 1.07 (0.93 to 1.23). These results were not materially altered by multivariate adjustment for age, BMI, family history of diabetes, and coronary risk factors. Comparable results were obtained when the analysis was restricted to symptomatic NIDDM as the outcome. We observed no appreciable modification of these associations by family history of diabetes or category of BMI. Duration of current or past use of postmenopausal hormones and dose of conjugated estrogen were not significantly related to incidence of NIDDM. Type of hormone (estrogen alone, progesterone alone, or combination) also did not appear to influence NIDDM risk. These prospective data indicate that postmenopausal hormone therapy is unlikely to be associated with a material increase in the incidence of NIDDM among women.
Effect of γ Subunit Carboxyl Methylation on the Interaction of G Protein α Subunits with βγ Subunits of Defined Composition

Abstract A baculovirus expression system was used to determine the contribution of carboxyl methylation of specific G protein γ subunits to the interaction between α and βγ subunits. βγ subunits were carboxyl methylated by a membrane bound methyltransferase in Sf9 cells, and periodate-oxidized adenosine inhibited this methylation by 90%. Carboxyl methylation of β1γ2, β2γ3, and β2γ7 enhanced pertussis toxin-catalyzed ADP-ribosylation of αi2 and αi3 by about 2-fold. On the other hand, methylation did not enhance membrane attachment of βγ subunits. These results suggest that methylation of isoprenylated γ subunits is required for optimal G protein-mediated signal transduction, but not membrane attachment.
Quality Control: A Challenge to Interior Design Educators

There is an increasing need to control the quantity and quality of interior design students entering the profession. A portfolio review initiated at the sophomore level has been introduced in an effort to improve the qualifications of the graduating interior design student at the University of Kentucky. This review is also perceived as a determining factor in making career decisions for the student. A first unofficial Sophomore Portfolio Review established the guidelines for interpreting the categories and presentation methodology for future reviews. Such a review process should impart earlier recognition of professional potential, produce high calibre graduates, and provide an enhanced reputation among design professionals.
Effect of the Liquid Film Thickness on the CO2 Corrosion of Steel

Abstract A corrosion cell was designed and built to study the effect of liquid film thickness on the CO2 corrosion of steel. It was found that greater liquid thicknesses led to higher corrosion rate. The main product formed by this reaction was iron (II) carbonate. The results are discussed in terms of compositional changes of the electrolyte near the electrode surface and corrosion precipitate properties.
Clinical utility of liver biopsy in patients with serum antibodies to the human immunodeficiency virus.

Abstract purpose: Patients with the acquired immunodeficiency syndrome (AIDS) frequently have liver dysfunction, which may be due to a number of causes. Determination of the patients who are likely to benefit from liver biopsy, an invasive procedure, is therefore important. In this study, the results of liver biopsy in patients with AIDS were compared to those in human immunodeficiency virus (HIV)-infected patients without AIDS. patients and methods: Thirty-six consecutive patients with antibodies to HIV present in the serum underwent liver biopsy from 1984 through 1988 at the Bronx Municipal Hospital. Twenty (56%) of the patients had AIDS diagnosed prior to the liver biopsy. Indications for the liver biopsy were unexplained fever in 83%, and abnormal serum levels of biochemical parameters of liver function in 89%. results: Liver biopsy was diagnostic in 18 cases (50%), including findings of hepatic infection by mycobacteria in 15, cytomegalovirus in two, and schistosoma in one; these infections had been previously detected at an extrahepatic site in only two cases. Helpful clinical information in 10 others included findings of granulomas of undetermined etiology in four, cirrhosis in five, and chronic persistent hepatitis in one. Patients with a diagnostic biopsy, as compared to patients with a nondiagnostic biopsy, had a statistically significant increase in the frequency of having AIDS diagnosed before the biopsy, longer duration of AIDS (in patients with AIDS diagnosed before the biopsy), greater number of different prior opportunistic infections, and a more elevated serum alkaline phosphatase level. For example, 70% of patients with AIDS, as compared to 25% of patients with serum antibodies to HIV but without AIDS, had diagnostic liver biopsies. Patients with a diagnostic biopsy also had statistically significantly more frequent pulmonary symptoms, possibly due to more frequent occurrence of Pneumocystis carinii pneumonia. In particular, the 15 patients with hepatic mycobacterial infection, as compared to the other patients, had a statistically significant increase in the frequency of having AIDS diagnosed prior to the biopsy, longer duration of AIDS, more frequent prior opportunistic infections, more severe leukopenia, and a more elevated serum alkaline phosphatase level. Liver biopsy was more sensitive than bone marrow aspiration and biopsy at detecting mycobacterial infection. conclusion: Liver biopsy, when indicated, is useful to detect opportunistic infection in HIV-infected patients who are not known to have AIDS.
Recrystallization kinetics: A coupled coarse-grained dislocation density and phase-field approach

During recrystallization, dislocation-poor grains grow and invade the heavily deformed dislocation-rich matrix. In this work, we develop a coupled dislocation density and phase-field method to model the isothermal recrystallization process as a phase transformation, driven by the stored elastic energy. Dislocations are represented in two spatial dimensions in terms of a continuous Burgers vector field, and their contribution to the elastic energy density is explicitly incorporated. A key feature of our approach is that the driving force for grain growth becomes nonlocal in space due to the presence of long-ranged dislocation strain fields. We employ the model to examine the influence of various spatially heterogeneous dislocation distributions (random, cellular, and algebraically correlated) on the growth morphology of an isolated recrystallized grain. Our results show that grain growth can be highly anisotropic and irregular in cellular dislocation networks, in agreement with recent experiments. The source of this anisotropy is related to the anisotropy of the underlying dislocation network as well as the long-ranged dislocation stress fields. We also discuss how to extend this method to three spatial dimensions by invoking the full dislocation density tensor.
Measurement and prediction of saturation-pressure relationships in three-phase porous media systems

Abstract Scaled multiphase versions of the Brooks-Corey and van Genuchten retention functions were used to describe saturation-capillary pressure curves measured in air-water, air-organic liquid and organic liquid-water systems in a sandy porous medium for four organic liquids during monotonic wetting phase drainage. Scaling was achieved by a linear transformation of capillary pressures using scaling coefficients which are shown to be closely predicted by ratios of measured interfacial tensions, providing that the latter are measured on fluids having contacted the porous media system. The multphhase version of the van Genuchten function described the experimental data with slightly greater precision than the Brooks-Corey function for all four organic liquid systems. A technique is introduced to ensure that when two-phase saturation-capillary pressure measurements are used to predict fluid behavior in three-phase systems, the estimated parameters imply an invariate pore geometry pertinent to the description of a rigid porous medium.
Impact of body mass index on the relationship between muscle quality and physical function in older women

Objectives To investigate the impact of body mass index (BMI) (normal weight, overweight, obese) on the relationship between muscle quality (MQ) and physical function in community-dwelling older women.
What We Argue About When We Argue About Regionalism

A new debate emerged in the 1990s about regional solutions to urban problems. The debate has been carried out overwhelmingly within a welfare economics framework that stresses the economic costs and benefits of regional governance structures. Unlike earlier debates about regional reforms, the new regionalists emphasize not just that more collaborative regional governance structures will improve local services but that they will enhance the competitiveness of regions in the global economy as well. The article surveys the evidence on two propositions put forth by the new regionalists: 1) whether fragmented regional governance harms economic growth; and 2) whether suburbs are dependent on cities for their economic well-being. Neither proposition is well supported by research and even if they were, the author concludes, this would not necessarily persuade citizens to support regional reforms. Research on the economic effects of regional governance needs to be supplemented with research on its political effects. The article concludes by examining the effects of regional governance structures on three core American political values.
An Accelerated Recursive Doubling Algorithm for Block Tridiagonal Systems

Block tridiagonal systems of linear equations arise in a wide variety of scientific and engineering applications. Recursive doubling algorithm is a well-known prefix computation-based numerical algorithm that requires O(M3(N/P + logP)) work to compute the solution of a block tridiagonal system with N block rows and block size M on P processors. In real-world applications, solutions of tridiagonal systems are most often sought with multiple, often hundreds and thousands, of different right hand sides but with the same tridiagonal matrix. Here, we show that a recursive doubling algorithm is sub-optimal when computing solutions of block tridiagonal systems with multiple right hand sides and present a novel algorithm, called the accelerated recursive doubling algorithm, that delivers O(R) improvement when solving block tridiagonal systems with R distinct right hand sides. Since R is typically ~ 102--104, this improvement translates to very significant speedups in practice. Detailed complexity analyses of the new algorithm with empirical confirmation of runtime improvements are presented. To the best of our knowledge, this algorithm has not been reported before in the literature.
Mechanism of Action of Cholecystokinin : A Not Atypical Brain-Gut Peptide

Brain-gut peptide action has been best studied in certain target cells of the gastrointestinal tract such as isolated pancreatic acini. Cholecystokinin (CCK) activation of pancreatic digestive enzyme secretion is initiated by specific receptors present in the basolateral membrane of the acinar cell. These receptors are highly selective for CCK and readily discriminate it from the homologous peptide, gastrin. Studies covalently crosslinking 125I-CCK to its receptor have revealed a binding glycoprotein subunit of Mr = 76,000 attached by a disulfide bridge to a Mr = 40,000 nonbinding subunit. Receptor occupancy leads to phosphotidylinositide breakdown and Ca2+ mobilization. Recent studies with the fluorescent chelate probe Quin-2 have shown that CCK increases cytosolic Ca2+ from a basal level of 100 nM to 500 approximately 1000 nM. The effects of Ca2+, and diacylglycerol produced by the breakdown of phosphoinositides, are believed mediated by activation of a group of protein kinases and phosphatases. CCK in the brain is present in neurons and is released from nerve endings by depolarization. The cellular mechanism of action of CCK, however, is essentially unknown. CCK application excites certain neurons but attempts to demonstrate effects on ion fluxes, phospholipid metabolism and protein phosphorylation have been negative to date. A possible explanations is provided by the finding that the brain CCK receptor shows differences in binding specificity from peripheral CCK receptors. Moreover, crosslinking studies reveal a single binding protein of Mr = 51,000. Thus, CCK may act differently in the brain and pancreas.
A comparison of self-report and chart audit in studying resident physician assessment of cardiac risk factors.

OBJECTIVE: To examine the relationship between resident physicians’ perceptions of their preventive cardiology practices and a chart audit assessment of their documented services.
Hydrocarbon synthesis from CO hydrogenation over Pd supported on SAPO molecular sieves

Abstract Palladium impregnated on silicoaluminophosphate molecular sieves (SAPO-5, SAPO-11, SAPO-34) and alumina has been studied during CO hydrogenation. Pd/SAPO-5, which exhibited the highest turnover frequencies, initially produced only methane and oxygenates (methanol and dimethyl ether), but catalyzed significant C 2 + hydrocarbon formation under the same conditions after temporary increase in gas contact time or exposure to propylene. While high yields of C 2 -C 4 alkanes were observed over Pd/SAPO-34, reaction over Pd/SAPO-11 and Pd/Al 2 O 3 yielded only oxygenates. Methane yields increased significantly with higher temperature, particularly over Pd/SAPO-5. Higher H 2 partial pressures increased oxygenate production and decreased C 2+ fractions. Many similarities between the results of this work and findings from studies of Pd/ZSM-5 indicate that hydrocarbon synthesis over Pd/SAPO catalysts occurs via a bifunctional pathway, involving methanol synthesis on Pd and autocatalytic conversion of oxygenates responsible for C 2+ hydrocarbons on the SAPO molecular sieves. Differences in the product distributions from Pd-impregnated molecular sieves arise mainly from the effect of acidity and shape selectivity in methanol conversion on the SAPO molecular sieves.
The radiation impedance of an electrodynamic tether with end connectors

Electrodynamic tethers are wires deployed across the earth's geomagnetic field through which a current is flowing. The radiation impedance of a tether with end connectors carrying an ac current is computed from classical antenna theory. This simulates the use of a tether on a space structure. It is shown that the current flow pattern at the tether connector is critical to determining the overall radiation impedance. If the tether makes direct electrical contact with the ionosphere then radiation impedances of the order of several thousand Ohms can be expected. If the only electrical contact is through the end connectors then the impedance is only a few Ohms for a dc current rising to several tens of Ohms for an ac current with frequencies in the whistler range.
Dihydropyridine Receptors and Type 1 Ryanodine Receptors Constitute the Molecular Machinery for Voltage-Induced Ca2+ Release in Nerve Terminals

Ca 2+ stores were studied in a preparation of freshly dissociated terminals from hypothalamic magnocellular neurons. Depolarization from a holding level of −80 mV in the absence of extracellular Ca 2+ elicited Ca 2+ release from intraterminal stores, a ryanodine-sensitive process designated as voltage-induced Ca 2+ release (VICaR). The release took one of two forms: an increase in the frequency but not the quantal size of Ca 2+ syntillas, which are brief, focal Ca 2+ transients, or an increase in global [Ca 2+ ]. The present study provides evidence that the sensors of membrane potential for VICaR are dihydropyridine receptors (DHPRs). First, over the range of −80 to −60 mV, in which there was no detectable voltage-gated inward Ca 2+ current, syntilla frequency was increased e -fold per 8.4 mV of depolarization, a value consistent with the voltage sensitivity of DHPR-mediated VICaR in skeletal muscle. Second, VICaR was blocked by the dihydropyridine antagonist nifedipine, which immobilizes the gating charge of DHPRs but not by Cd 2+ or FPL 64176 (methyl 2,5 dimethyl-4[2-(phenylmethyl)benzoyl]-1 H -pyrrole-3-carboxylate), a non-dihydropyridine agonist specific for L-type Ca 2+ channels, having no effect on gating charge movement. At 0 mV, the IC 50 for nifedipine blockade of VICaR in the form of syntillas was 214 nm in the absence of extracellular Ca 2+ . Third, type 1 ryanodine receptors, the type to which DHPRs are coupled in skeletal muscle, were detected immunohistochemically at the plasma membrane of the terminals. VICaR may constitute a new link between neuronal activity, as signaled by depolarization, and a rise in intraterminal Ca 2+ .
Calculations relating to the experimental observation of resonances in the H+H2 reaction

Abstract The log derivative version of the Kohn variational principle is used to calculate both integral and differential cross sections for H+H 2 (ν=0, j =0)→H 2 (ν′= 1, j ′=1, 3)+H in the energy range E total =0.95–1.35 eV. The computed integral cross sections agree very well with the earlier results of Zhang and Miller, providing strong evidence for the reliability of both calculations. The computed differential cross sections exhibit certain resonant structure in the neighbourhood of the backward direction (θ=180°), but this structure does not bear much relation to the recent experimental results of Nieh and Valentini. Several possible sources of error in the present “ab initio” quantum scattering calculations are carefully reviewed.
Mechanism of cholesterol efflux from cells

Abstract Experiments have been conducted to gain information on the mechanisms underlying the surface transfer of free cholesterol between cells and extracellular cholesterol acceptors. The movement of radiolabeled cholesterol has been monitored using hepatoma cells, fibroblasts, and primary hepatocytes as cholesterol donors and phospholipid vesicles as acceptors. The data obtained from these studies are compared to those obtained from studies using two populations of phospholipid vesicles; one contained labeled cholesterol, which served as a donor, while the second population acted as an acceptor. In the presence of phospholipid vesicles, the loss of cholesterol from the cells follows first order kinetics if the data are corrected for the changing specific activity produced by the initiation of cholesterol synthesis. In hepatoma cells, at least two-thirds of the cellular cholesterol is in one kinetic pool. The activation energy for transfer of cholesterol from hepatoma cells to unilamellar vesicles was determined to be 12 kcal/mole. A similar value of 16 kcal/mole was obtained in the vesicle/vesicle system. The transfer of cholesterol between vesicles was shown to be independent of acceptor concentration, whereas the half-time for the movement of cholesterol between cells and vesicles was shown to be a function of the extracellular vesicle concentration. Analysis and comparison of the parameters describing the kinetics of cholesterol transfer in these systems suggests that the mechanism involves diffusion of cholesterol molecules through the aqueous phase, with the overall rate being influenced by the rate of desorption from the donor phospholipid-cholesterol bilayer membrane. The differences observed between the two experimental systems, particularly with regard to the influence of acceptor concentration, is attributed to the effects of the presence of a large unstirred water layer around cells which is not present around vesicles.
Dynamic Modeling of an Electric Wheelchair

The development of a dynamic model for the standard electric wheelchair is described. A computer simulation of the nonlinear differential equations of motion that resulted was developed. In order to verify the modeling process, an electric wheelchair was instrumented to record rear wheel velocities and caster orientations as a function of time. The simulation program has been used to study appropriate control algorithms to be implemented in a new digital controller design for the electric wheelchair.
Trans-synaptic regulation of adrenergic neuron development: inhibition by ganglionic blockade.

Abstract To determine whether acetylcholine mediates the trans-synaptic regulation of tyrosine hydroxylase (T-OH) activity in developing mouse superior cervical ganglion (SCG), neonatal animals were treated with long-acting ganglionic blocking agents. Chlorisondamine and pempidine prevented the normal development of T-OH activity in postsynaptic neurons of the SCG. Ganglionic blockade was not associated with enzyme inhibition in vivo , and these agents did not inhibit T-OH activity in vitro . The development of ganglion T-OH activity was sensitive to ganglion blockade throughout the first month of life. Furthermore, treatment with chlorisondamine chronically reproduced the effects of ganglion decentralization in preventing the normal increase in T-OH activity. These results suggest that presynaptic neurons regulate the development of T-OH activity in mouse SCG through release of acetylcholine and consequent depolarization of adrenergic neurons.
Dynamic self assembly of confined active nanoparticles

Abstract We report the dynamic self-assembly of chemically propelled nanoscale building blocks (NBBs) under confinement using reactive molecular dynamics simulations. The NBBs are hollow rectangles with one side open (tail) to expose the catalysts inside to the fuel environment. Adjacent NBBs can self assembly into tail–tail or tail–head (the side opposite to the tail) pairs. It was found that chemical propulsion forces unlock many tail–tail pairs but not tail–head pairs. Although the distributions of both tail–tail and tail–head pairs are orientation-dependent with respect to the confining wall, the effect of chemistry seems to be orientation-independent.
Count rate studies of a box-shaped PET breast imaging system comprised of position sensitive avalanche photodiodes utilizing monte carlo simulation.

Abstract We are investigating a high-sensitivity, high-resolution positron emission tomography (PET) system for clinical use in the detection, diagnosis and staging of breast cancer. Using conventional figures of merit, design parameters were evaluated for count rate performance, module dead time, and construction complexity. The detector system modeled comprises extremely thin position-sensitive avalanche photodiodes coupled to lutetium oxy-orthosilicate scintillation crystals. Previous investigations of detector geometries with Monte Carlo indicated that one of the largest impacts on sensitivity is local scintillation crystal density when considering systems having the same average scintillation crystal densities (same crystal packing fraction and system solid-angle coverage). Our results show the system has very good scatter and randoms rejection at clinical activity ranges (≈200 μCi).
MAINTENANCE OF THERAPEUTIC CHANGE BY MOMENTARY DRO

Differential reinforcement of other behavior (DRO) involves delivery of reinforcement at the end of an interval during which the target behavior has not occurred. Momentary DRO, however, is a procedure in which reinforcement is delivered if a response did not occur at the end of an interval. We examined the extent to which momentary DRO maintained suppression, following initial treatment with whole-interval DRO, of nine retarded students' maladaptive behavior. Results indicate that momentary DRO maintained response suppression comparable to that obtained by whole-interval DRO.
Atherosclerosis and AD: analysis of data from the US National Alzheimer's Coordinating Center.

Background: Epidemiologic studies have implicated cerebrovascular disease and its antecedents as risk factors for Alzheimer disease (AD). Cerebral atherosclerosis or strokes may increase the deposition of neuritic plaques or the formation of neurofibrillary tangles. Alternatively, they may simply hasten the age at onset of disease, or increase the severity of disease symptoms. This investigation examined the association between cerebrovascular disease and the pathologic manifestations of AD in an autopsy series. Methods: This was a cross-sectional study using data from the United States National Alzheimer’s Coordinating Center database. The primary analysis included 1,054 individuals with clinical information and semiquantitative neuropathologic measurements: 921 had AD as the primary neuropathologic diagnosis and 133 were considered neuropathologically normal. Results: Overall, 9% of the individuals had clinical history of stroke during life, but 33% had evidence of cerebral infarcts at postmortem. There was no association between neuritic plaques or neurofibrillary tangles, the primary neuropathologic manifestations of AD, with either clinical history of stroke or the presence of cerebral infarcts at postmortem. The authors did find a higher frequency of neuritic plaques and neurofibrillary tangles with increased amyloid angiopathy. Neither plaques nor tangles were associated with small vessel cerebrovascular disease, arteriosclerosis. However, the presence of large-vessel cerebrovascular disease, or atherosclerosis, was strongly associated with an increased frequency of neuritic plaques. Conclusions: Atherosclerotic cerebrovascular disease may have a role in the pathogenesis of Alzheimer disease, because of a strong association with frequent neuritic plaques.
Global Calculations of Tidal Loading

THE discrepancy between Earth-tide theory and Earth-tide observations is mostly the result of the influence of the tides in the oceans1–5, which can easily account for 10%, 20% and 90% of the total Earth tide in gravity, strain and tilt, respectively. These ocean load perturbations can be used to study the upper mantle (in regions where the ocean tide is particularly well known) and the ocean tides themselves. Near large bodies of water it is the region of ocean closest to the observation site that causes most of the Earth-tide perturbation. Models which ignore the rest of the world's oceans reproduce the observed effects well2,3, one reason for this being that the ocean tide circulates around a dozen or so nodal points, or amphidromes, the circularly symmetric nature of an amphidrome causing a first order cancellation in the load at great distances.
Fluorescence-lifetime-based phase-sensitive sensor array with LED or diode laser excitation for chemical- and biosensing

Fluorescence lifetime-based sensors are well-suited for chemical and biological applications since they are relatively insensitive to background light intensity, fluctuations and bleaching of fluorophores. Examples of applications include biosensing strategies where binding or a target analyte to an immobilized biological receptor molecule results in a change in the fluorescence lifetime of a fluorescent reporter group. It is desirable in many instances to have a sensor array to monitor the simultaneous binding of several analytes. We have designed a multichannel system using LEDs (or laser diodes) to excite fluorescence, multiple photodetectors, and a multichannel computer algorithm-based phase meter. The multichannel phase meter utilizes a PC and multichannel digital acquisition board. The resolution of each channel in the multichannel phase meter has been estimated at approximately 0.05 degrees. The eigen-phase fluctuations for each channel of the system are approximately 0.15 degrees, which allow us to estimate the lifetime resolution as better than 10 ps. We estimate the processing time of phase measurements for each channel as less than 200 ms. The usefulness of the system has been demonstrated in several operational examples, including a multichannnel pH meter and a fluoresphore competitive immunoassay-based chemical sensor.
Mapping the orientation of intravoxel crossing fibers based on the phase information of diffusion circular spectrum

A new method is presented to map the orientation of intravoxel crossing fibers by using the phase of the diffusion circular spectrum harmonics. In a previous study [Zhan, W., Gu, H., Xu, S., Silbersweig, D.A., Stern, E., Yang, Y., 2003. Circular spectrum mapping for intravoxel fiber structures based on high angular resolution apparent diffusion coefficients. Magn. Reson. Med. 49, 1077–1088], we demonstrated that the magnitude of the 4th-order harmonic of the diffusion circular spectrum can be used to identify the existence of fiber crossings. However, the orientation of the intravoxel crossing fibers remained unknown. This study extends the diffusion circular spectrum mapping method so that it is able to identify the orientation of the intravoxel crossing fibers by utilizing the phase information of the circular spectrum. In general, the phase of the circular harmonic determines the rotation of the apparent diffusion coefficient (ADC) profile on the sampling circle that is spanned by the major and medium eigenvector of the diffusion tensor and thus can be used to determine the orientation of the crossing fibers. Simulation results show that the regular tensor-based major eigenvector maps have obvious artifacts in the fiber-crossing area, whereas the estimated crossing fibers by the proposed method are much more consistent with the orientation of the actual intravoxel fibers. Diffusion MRI experiments were performed on five healthy human brains using a 3T scanner. The brain regions with fiber crossings were selected by thresholding the magnitudes of the 4th-order circular spectrum map. Intravoxel crossing fibers were estimated by the phase of the 4th-order harmonic for each voxel within these areas. The estimated intravoxel crossing fibers demonstrated a clear consistency with the orientations of fiber tracks in the surrounding tissues, reducing the fiber orientation discontinuity of the regular major eigenvector map.
Initiated chemical vapor deposition of antimicrobial polymer coatings.

Abstract The vapor phase deposition of polymeric antimicrobial coatings is reported. Initiated chemical vapor deposition (iCVD), a solventless low-temperature process, is used to form thin films of polymers on fragile substrates. For this work, finished nylon fabric is coated by iCVD with no affect on the color or feel of the fabric. Infrared characterization confirms the polymer structure. Coatings of poly(dimethylaminomethyl styrene) of up to 540 μg/cm2 were deposited on the fabric. The antimicrobial properties were tested using standard method ASTM E2149-01. A coating of 40 μg/cm2 of fabric was found to be very effective against gram-negative Escherichia coli, with over a 99.99%, or 4 log, kill in just 2 min continuing to over a 99.9999%, or 6 log, reduction in viable bacteria in 60 min. A coating of 120 μg/cm2 was most effective against the gram-positive Bacillus subtilis. Further tests confirmed that the iCVD polymer did not leach off the fabric.
Bayesian solutions to non-Bayesian detection problems: Unification through fusion

In 1950 Abraham Wald proved that every admissible statistical decision rule is either a Bayesian procedure or the limit of a sequence of such procedures. He thus provided a decision-theoretic justification for the use of Bayesian inference, even for non-Bayesian problems. It is often assumed that his result also justified the use of Bayesian priors to solve such problems. However, the principles one should use for defining the values of prior probabilities have been controversial for decades, especially when applied to epistemic unknowns. Now a new approach indirectly assigns values to the quantities usually interpreted as priors by imposing design constraints on a detection algorithm. No assumptions about prior "states of belief are necessary. The result shows how Wald's theorem can accommodate both Bayesian and non-Bayesian problems. The unification is mediated by the fusion of clairvoyant detectors.