cssi/SciSciGPT-SciSciNet huggingface dataset:
Real-time electron counting studies on charge fluctuations in a semiconductor quantum dot (Invited Paper)

We present time-domain electron counting studies on charge fluctuations in a mesoscopic system. In this measurement, a radio-frequency single-electron transistor (RF-SET) acting as a fast electrometer is capacitively coupled to a quantum dot (QD) electrostatically defined in a GaAs/AlGaAs heterostructure. Random telegraph signals (RTSs) were observed on the RF-SET and were interpreted as resulting from individual electrons tunneling into/out of the QD hence switching the QD charge state between N and N+1 electrons near the charge degeneracy point. Periodic behavior of the switching events is observed as the number of average electrons in the electron box is decreased one by one. The occupation time of the excess electron is directly measured and changes from a few microseconds to a few milliseconds as the tunneling resistance of the QD is increased. Histogram of the occupation time obtained from the time-domain electron counting measurements agrees well with the frequency-domain power spectrum analysis, both suggesting a Poissonian process at the charge degenerate point, in agreement with a model consisting of two charge states. Real time electron counting techniques can play a powerful role in studies on temporal electronic correlations, as well as quantum information processing schemes. Techniques that will improve the charge sensitivity of the RF-SET will also be discussed.
Strontium distributions in sea water profiles from the Geosecs I (Pacific) and Geosecs II (Atlantic) test stations

Abstract Strontium has been determined in Geosecs I and II test station profiles by mass spectrometric isotope dilution (MSID) analysis and atomic absorption spectrophotometry. The Geosecs I profile shows a range in μg Sr/g salinity from 218 to 223 by MSID and Long Island Sound water yields a value of 214. A maximum is indicated in Geosecs I at a depth of about 500 meters as outlined by the atomic absorption data. Comparison of atomic absorption data for the Atlantic and Pacific test stations through standardization by MSID indicates that the deep Atlantic is about 1.5% lower in Sr/salinity than the deep Pacific. As the differences are about as large as the coefficient of variation, future results will be made exclusively by MSID with a much smaller error.
PROLONGED MECHANICAL VENTILATION OF PRETERM LAMBS LEADS TO SMOOTH MUSCLE EXTENSION AND ELASTIN ACCUMULATION ALONG PULMONARY BLOOD VESSELS.† 1923

Chronic lung injury from prolonged mechanical ventilation after premature birth is characterized in part by pulmonary edema and sustained pulmonary vascular resistance (PVR) (Bland et al; FASEB J 9:A275, 1995). These observations suggest that chronic lung injury after premature birth may be associated with abnormal structural development of the pulmonary circulation. We tested this hypothesis by determining smooth muscle extension and elastin accumulation along pulmonary arteries (PAs) and veins (PVs) in 3 groups of lambs. 5 preterm lambs each were mechanically ventilated at 60 breaths/min(tidal volume 5 ± 2 ml/kg) or 20 breaths/min (tidal volume 15 ± 5 ml/kg) for 3-4 wks postnatally. Inspired O2 was adjusted to keep PaO2 ≈60-90 mmHg. 5 term lambs <24 h old served as gestation-matched controls. Lung lobes were fixed by clamping them at the prevailing inflation pressure. Paraffin-embedded tissue sections were analyzed for vascular smooth muscle extension (trichrome stain) and elastin accumulation (Hart's elastic fiber stain) along PAs and PVs by quantitative histology (mean ± SD; *:p < 0.05 vs control). Muscularization of PAs and elastin accumulation in PAs and PVs may contribute to the histologic and extravascular lung water content evidence of pulmonary edema, and the sustained PVR by increasing the filtration pressure and resistance along the pulmonary microcirculation. (Supported by March of Dimes #6 FY95 0981)Table
Soybean actin, heat shock protein, and ribosomal protein promoters direct tissue-specific transgene expression in transgenic soybean.

Soybean (Glycine max) promoters from an actin gene (GmActin), a ribosomal protein S11 gene (GmRpS11) and a heat shock protein 90 gene (GmHsp90), identified as being active during early induction of soybean somatic embryogenesis, were cloned, fused to the green fluorescence protein (gfp) gene and reintroduced into soybean for evaluation. All promoters displayed development- and tissue-specific regulation based on the expression of GFP in transgenic soybean. In seedlings, these three promoters gave rise to strong GFP expression in young roots, with very high levels of expression in the vascular tissues and root primordia. In older plants, promoter activity was observed in the vascular cambium of petioles, leaf midribs, and in the mesophyll of expanding leaves, but at reduced levels. The GmActin promoter gave very high GFP expression in developing and mature seeds. All three promoters displayed high activity following induction of somatic embryogenesis from immature soybean cotyledons. Comparison of promoter-regulated GFP transgene expression with transcriptome analysis using RNA-Seq revealed agreement in expression intensity in roots, leaves, and flowers but exceptions for expression in young developing seeds. Evaluation of specific promoters in transgenic plants is needed for proper elucidation of promoter-regulated transgene activity.
On computing the split-radix FFT

This paper presents an efficient Fortran program that computes the Duhamel-Hollmann split-radix FFT. An indexing scheme is used that gives a three-loop structure for the split-radix FFT that is very similar to the conventional Cooley-Tukey FFT. Both a decimation-in-frequency and a decimation-in-time program are presented. An arithmetic analysis is made to compare the operation count of the Cooley-Tukey FFT fo several different radixes to that of the split-radix FFT. The split-radix FFT seems to require the least total arithmetic of any power-of-two DFT algorithm.
Kinetic Study of the Reaction of Acetaldehyde with OH

The reaction of OH with acetaldehyde in the gas phase has been studied by tunable infrared laser kinetic spectroscopy. As expected, the main channel is the production of water (∼100%). An upper bound of 5% was placed on the yield of CH3, and the yield of H is estimated as 5 ± 5%. A rate constant of 1.67(10) × 10-11 molecules-1 cm3 s-1 is obtained for the title reaction, in good agreement with previous measurements. The major product of the reaction, CH3CO, reacts with O3, producing CH3, CO2, and O2 in one channel with a rate constant of 1.4(5) × 10-11 molecules-1 cm3 s-1 and producing CH3CO2 and O2 in the other channel with a rate constant of 3.3(5) × 10-11 molecules-1 cm3 s-1.
Vacancies near semiconductor surfaces

We present a calculation of the bound-state energy levels of ideal vacancies near and on a semiconductor surface. We consider the (110) surface of GaAs and also a model for more ionic semiconductors with the zinc blende crystal structure. We find that the vacancy energy levels are not greatly perturbed (by less than 0.1 eV) as the vacancy is moved toward the surface until the vacancy reaches the second layer of atoms from the surface. At this point the highest occupied level in the neutral anion vacancy moves to lower energy, and the highest-energy state occupied in the neutral cation vacancy moves to higher energy. As more ionic materials are considered, we find that the anion vacancy levels move toward and eventually into the conduction band, while the cation vacancy levels move toward and eventually into the valence band. These results suggest that the recently proposed defect model for Schottky-barrier formation is capable of accounting for experimentally observed trends in Schottky-barrier behavior.
Chemical synthesis of acyl thioesters of acyl carrier protein with native structure

Abstract The acyl carrier protein (ACP) of Escherichia coli was converted to acyl-ACP by imidazole-catalyzed S-acylation with N-acylimidazole. The acylation was specific to the sulfhydryl group; no acylation of tyrosine or amino groups of the protein occurred. The acyl-ACP substrates synthesized had a native structure as determined by gel electrophoresis, hydrophobic chromatography, and enzymatic activity. N-Acylimidazoles are readily synthesized and permit preparation of those acyl-ACP substrates that cannot be produced enzymatically.
A revision of Vernonia series Buddleiifoliae (Compositae: Vernonieae)

SeriesBuddleiifoliae of the genusVernonia of southeastern South America consists of 18 species which are keyed, described, discussed and mapped.Vernonia goiasensis is proposed as a new name, whileV. wasshausenii andV. monocephala subsp.irwinii are described as new taxa, and V.asteriflora subsp.kuntzei is presented as a new combination.
Estimating the biomass of freshwater mussels (Bivalvia: Unionidae) from shell dimensions

We have compared the convenience and accuracy of two models using 6 shell dimensions for predicting 4 biomass parameters for 4 species of southern U.S.A. unionids (Quadrula quadrula, Q. pustulosa, Lampsilis anodontoides, and Amblema perplicata). Prediction of whole wet weight, tissue wet weight, tissue dry weight, and shell dry weight as a linear function of (shell length)3 was accurate, even with extremely small sample sizes. In addition, this method is very convenient for field use because it requires one simple, unambiguous shell measurement.
Emissions from open burning of used agricultural pesticide containers.

Abstract Emissions from simulated open burning of used agricultural pesticide containers were sampled for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs), polycyclic aromatic hydrocarbon compounds (PAHs), and particle matter (PM10 and PM2.5). Clean high density polyethylene (HDPE) containers, containers with trace pesticide, and triple-rinsed containers were burned separately in an open combustion facility and their emissions compared. Two common chlorinated pesticides were used: 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine (atrazine). PCDD/PCDF emission factors ranged from 0.1 to 24 ng toxic equivalents (TEQ)/kg C burned with a mean and median of 4.9 and 1.9 ng TEQ/kg C burned, respectively. In a limited number of trials, the trace 2,4-D in the HDPE container led to a statistically significant increase in PCDD/PCDF formation compare to all other conditions. Residual atrazine did not lead to more PCDD/PCDF than the unrinsed 2,4-D container. Total (16 compounds) PAH emission factors varied from 1.5 to 6.7 mg/kg C burned. These limited data suggest that rinsing the 2,4-D container prior to burning reduces both PCDD/PCDF and PAH emissions. Nine PM2.5 emission factors ranged from 9 to 35 mg/g C burned and ten PM10 values ranged from 6 to 43 mg/g C burned. Neither pesticide appeared to have any effect on PM concentration.
Phase height measurements of the E-region

Abstract A phase-path sounder with spaced receivers and not requiring ultra-stable oscillators is described. Measurements of the morning variation in the E -layer height using this equipment are reported. From these measurements made in March 1968 a scale height of about 7 km is calculated.
Isoelectric focusing of interacting systems III. Carrier ampholyte-induced macromolecular association or dissociation into subunits.

A phenomenological theory of isoelectric focusing of interacting systems (Cann, J. R., and Stimpson, D. I. Biophys. Chem., 7, 103, (1977) has been extended to include carrier ampholyte-induced dimerization or dissociation of a subunit macromolecule. Equilibrium as well as transient focusing patterns can show two well-resolved peaks similar to the patterns for a mixture of two noninteracting macromolecules. Characteristically, one of the peaks in the transient pattern grows at the expense of the other, which under certain conditions may disappear completely as equilibrium is approached. The implications of these findings for conventional applications of isoelectric focusing and for the detection and characterization of macromolecular interactions are discussed.
Oral pyridostigmine administration in rats: effects on thermoregulation, clinical chemistry, and performance in the heat.

We have recently reported that acute intraperitoneal administration of pyridostigmine bromide to rats resulted in significant decrements in physical performance in the heat, adverse thermoregulatory effects, and exacerbated elevations in several indices of heat/exercise injury. Since it will be consumed orally as a prophylaxis for organophosphate poisoning, pyridostigmine was dissolved in the drinking water of rats. Consumption of pyridostigmine for 7 days (n=34, 6.6 mg/day) resulted in a 23% (p<0.001) reduction of circulating cholinesterase when compared with a control group (n=31) while ingestion for 14 days (n=35, 8.9 mg/day) elicited a 39% (p<0.001) inhibition of circulating cholinesterase when compared to a second control group (n=33). Water and food consumption, rate of weight gain, and overt behavior were unaffected by pyridostigmine consumption. When approximately half the animals in each group were exercised (9.14 m/min) in the heat (35°C) to hyperthermic exhaustion (Tre=42.5–43°C, rats unable to right themselves), pyridostigmine consumption for 14 days effected a significantly (p<0.05) increased rate of weight loss, but no further effects on thermoregulation or performance were noted. Several minor increments were observed in clinical indices of heat/exercise injury in rats consuming pyridostigmine for 14 days. These data indicate that oral dosages of pyridostigmine can be probably be titrated to levels of cholinesterase inhibition which are efficacious in prophylaxis against organophosphate toxicity without significant effects on selected physiologic and metabolic processes.
DECILIATION IN THE AMPULLA OF THE RAT OVIDUCT AND EFFECTS OF ESTROGEN ON THE PROCESS

The mechanism by which cells in the ampullae of the rat oviducts undergo rapid deciliation during each estrous cycle and the effects of estrogen on the ciliated cells were examined. Untreated rats were killed on each day of the 5-day estrous cycle, and the ampullae of their oviducts were removed. Other rats were injected subcutaneously each day for 5 days with 0.3 microgram or 3.0 micrograms of estradiol benzoate or with 0.3 mg of tamoxifen, an estrogen antagonist, per kilogram of body weight. The ampullae of the oviducts of the treated rats were excised on the day following the last injection. The tissues from all the rats were fixed in glutaraldehyde, stained with uranyl acetate and lead citrate, and examined with a transmission electron microscope. Deciliation of cells was seen to occur by membrane-bound cilia packets (CPs) forming at the apices of cells and pinching off. Although CPs were more numerous at proestrus, they were also observed at estrus, diestrus-1, and diestrus-2, suggesting that the process of deciliation is an ongoing one that merely changes in rate. No evidence of resorption of cilia was seen. Estradiol treatment did not prevent CPs from forming, nor was tamoxifen treatment associated with any apparent enhancement of deciliation. Ciliated cells with CPs stained more darkly than ciliated cells that were without CPs, and the former appeared similar in their staining characteristics to secretory cells, most of which stain darkly. It was concluded that the cells of the ampulla deciliate rapidly by shedding their cilia into the lumen of the oviduct, that estrogen does not halt the process, and that ciliated cells may be transformed to secretory cells following loss of their cilia.
The limits of hedonism: Feldman on the value of attitudinal pleasure

1. Among theories of the good life, hedonism is often regarded as both the simplest and the least plausible. It is a simple theory in that it identifies one good only pleasure as having prudential value.1 But it is implausible because of this simplicity, as a result of which it is accused of supporting unduly narrow judgements about prudential value, holding that only a life of sensual contentment is valuable, and overlooking the fact that our lives go better or worse for us if we acquire other things we desire, or if we obtain intrinsic goods such as knowledge and friendship. Fred Feldman's Pleasure and the Good Life sets out to demolish both these widely held theses about hedonism.2 Hedonism, Feldman shows, is not the simple theory its critics claim it is, nor is it implausibly restrictive in its range of judgements about the good life. When properly understood, it is a malleable, or, as he puts it, a "plastic" theory that allows of different interpretations, some of which accommodate claims about the good life that have traditionally been seen as paradigmatically non-hedonist, and indeed, anti-hedonist. His argument unfolds in two main steps. The first step consists in arguing that what has prudential value,3 according to the hedonist, is not, as is often thought, sensory pleasure, that is, pleasure as a feeling or tingle or a sensation, but attitudinal pleasure, that is, favourable attitudes towards some state of affairs such as enjoying it, being pleased about it, being glad it is happening, being delighted by it, and so on (p. 56). Sensory and attitudinal pleasures are distinct phenomena, although they can be related. It is possible for someone to experience attitudinal pleasure in having sensory pleasures we often enjoy having
Specificity analysis of monoclonal anti‐DNA antibodies from B6‐1Pr/1Pr mice

The binding properties of B6-lpr/lpr anti-DNA monoclonal antibodies were characterized to evaluate the influence of genetic background on the diversity and specificity of lpr-induced autoantibody responses. Six anti-DNA antibodies were produced from fusions with B6-lpr/lpr mice, while another was obtained from a fusion with a B6-+/+ mouse immunized with lipopolysaccharide. Each antibody bound single-stranded DNA in preference to double-stranded DNA, with variation of over 300-fold in relative binding activities. In terms of binding to a panel of synthetic polynucleotides, each antibody exhibited a unique antigenic specificity. This binding, however, was not dependent on recognition of a unique base or sugar moiety, since individual antibodies bound polymers of dissimilar composition. These results suggest a diversity of binding reactions for B6-lpr/lpr anti-DNA antibodies, with a clonal repertoire similar to that of mice from autoimmune backgrounds.
The effect of food deprivation on self-control.

Two experiments examined the effect of food deprivation on choice in a discrete-trials self-control paradigm, choice between a larger, more-delayed reinforcer and a smaller, less-delayed reinforcer. In Experiment 1, four pigeons were each deprived to 65%, 80%, and 90% of their free-feeding weights, and the delay to the smaller reinforcer was varied. Deprivation level did not affect choice, but the rate of ineffective key pecks made during the reinforcer delays increased as deprivation increased. In Experiment 2, four pigeons were exposed to conditions in which they were fed up to their 80% free-feeding weights following experimental sessions, and in which they were given no postsession feedings. Both the pigeons' weights and their latencies to insert their heads into the food hopper when food was available were lower when the pigeons were not fed following experimental sessions. Choice showed no change. Deprivation level affects response rate and eating behavior in these procedures, but not choice.
When betamethasone and dexamethasone are unavailable: hydrocortisone.

OBJECTIVE: To review the literature on alternatives to betamethasone and dexamethasone for enhancement of fetal lung maturity. STUDY DESIGN: A medline search was conducted from 1966 to the present. Trials dealing with enhancement of fetal lung maturity using modalities other than betamethasone or dexamethasone were reviewed. RESULTS: Eight studies met inclusion criteria. Excluding betamethasone and dexamethasone, the most frequently studied glucocorticoids, for fetal lung maturation, are methylprednisolone and hydrocortisone. Methylprednisolone does not cross the placenta. Two grams of hydrocortisone has been shown to improve indices of fetal lung maturity (i.e., L/S ratio) and to improve fetal outcomes compared to no treatment. CONCLUSION: There is limited information about alternatives to betamethasone and dexamethasone for the enhancement of fetal lung maturity in women at risk of preterm delivery. In the absence of these two preferred drugs, hydrocortisone can be given at a dose of 500 mg intravenously every 12 hours for four doses for this indication.
Effect of anti-CD18 antibody on myocardial neutrophil accumulation and infarct size after ischemia and reperfusion in dogs.

BACKGROUND Polymorphonuclear neutrophils (PMNs) accumulate in postischemic myocardium and may cause injury to myocardium or to vessels by production of oxygen free radicals or by release of proteases and lipases. PMN accumulation is dependent on adherence to endothelium, which is mediated by a family of glycoproteins on the PMN surface, each of which has a common beta-subunit (CD18). The purpose of this study was to determine whether an antibody (IB4) against the CD18 protein could attenuate PMN accumulation and limit myocardial infarct size. METHODS AND RESULTS F(ab')2 fragments of a mouse monoclonal antibody to human adherence-promoting leukocyte glycoprotein (CD18) were used. Infarct size after 90 minutes of ischemia and 3 hours of reperfusion was compared in dogs with (n = 8) and without (n = 8) the anti-CD18 treatment. Myocardial PMN accumulation was assessed with 111In-labeled autologous PMNs. Anti-CD18 treatment significantly reduced the number of PMNs in the ischemic region (19,123 +/- 5,352/mg versus 5,204 +/- 927/mg in the control and treated groups, respectively; p < 0.05). In addition, the ratio of myocardial blood flow (ischemic/nonischemic wall) at 45 minutes into reperfusion was higher in the treated than in the control group (1.18 +/- 0.18 versus 0.69 +/- 0.09; p < 0.05). Nevertheless, infarct size was similar between the control and treated groups (40.5 +/- 7.4% versus 48.5 +/- 4.4% of the area at risk; p = NS). Transmural mean collateral blood flow to the ischemic myocardium was similar between the two groups, and the inverse relation between infarct size and collateral blood flow was not shifted by anti-CD18 therapy. CONCLUSIONS Although PMN accumulation contributed to reduced postischemic microvascular perfusion, it caused insufficient additional myocardial cell death to measurably affect infarct size in this model.
A scaling technique for studying the dynamics of high mass ions in Fourier transform mass spectrometry : a preliminary report

Abstract The signals that have been observed for high mass biomolecule ions in Fourier transform mass spectrometry (FTMS) are characterized by low signal-to-noise and low resolution at low ion number whereas the spectral peaks for more moderate mass ions are good with high signal and resolution. We have proposed that the behavior of target high mass ions can be experimentally investigated with low mass ions at lower magnetic inductions. The justification of this proposal derives from the observation that solutions to the equations of motion for high and low mass ions are the same if the time parameter of the solution is scaled, and if the appropriate adjustments to the magnet induction are made. New results obtained for the molecular ion of benzene at lower magnet inductions support the relevance of scaled experiments for studying problems that occur at high mass. High mass ions modeled with the benzene molecular ion show good signal and resolution that degrades as the target mass is increased. Increasing the ion number improves the signal and resolution. Compensating the cubic trap improves signal and resolution for moderate ion numbers. This suggests a partial remedy for the problems at high mass.
β-Carotene and protein oxidation : effects of ascorbic acid and α-tocopherol

The effect of beta-carotene on protein oxidation was examined under different oxygen (O(2)) tensions and with other antioxidants: alpha-tocopherol, ascorbic acid, and mixtures of antioxidants. Human serum albumin (HSA) was incubated with 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) to induce protein oxidation (carbonyl formation), under 15, 150, and 760 torr of O(2) tension. Antioxidant activity was related to O(2) tension, antioxidant concentrations and interaction between mixtures of antioxidants: (1) Under 15 torr of O(2), incubating HSA with AAPH, 1. 6 microM beta-carotene, 80 microM alpha-tocopherol, 160 microM ascorbic acid, and mixtures (0.1 microM beta-carotene, 5.0 microM alpha-tocopherol and 10 microM ascorbic acid) resulted in 24, 29, 39, and 44% reduction of carbonyl formation, respectively. (2) Under 150 torr of O(2) tension, the antioxidant effect of beta-carotene was decreased by 4% but increasing O(2) tension did not diminish the antioxidant effects of alpha-tocopherol, ascorbic acid, or antioxidant mixtures. (3). Under 760 torr of O(2) tension, adding 1. 6 microM beta-carotene resulted in 26% more carbonyl formation. (4) Under 760 torr of O(2) tension, the antioxidant effect of ascorbic acid was decreased 32% compared to what was observed at 150 torr of O(2) tension. Changes in O(2) tension had no effect on the antioxidant effect of alpha-tocopherol. The mixture of antioxidants inhibited carbonyl formation by 37% and was 7% less effective than that of 15 and 150 torr of O(2) tension. High concentration of beta-carotene produces more protein oxidation in the presence of high O(2) tension by a prooxidant mechanism. Mixtures of beta-carotene, alpha-tocopherol, and ascorbic acid provided better protective effects on protein oxidation than any single compound.
Femtosecond Time-Resolved Stimulated Raman Spectroscopy: Application to the Ultrafast Internal Conversion in β-Carotene†

We have developed the technique of femtosecond stimulated Raman spectroscopy (FSRS), which allows the rapid collection of high-resolution vibrational spectra on the femtosecond time scale. FSRS combines a sub-50 fs actinic pump pulse with a two-pulse stimulated Raman probe to obtain vibrational spectra whose frequency resolution limits are uncoupled from the time resolution. This allows the acquisition of spectra with <100 fs time resolution and <30 cm(-1) frequency resolution. Additionally, FSRS is unaffected by background fluorescence, provides rapid (100 ms) acquisition times, and exhibits traditional spontaneous Raman line shapes. FSRS is used here to study the relaxation dynamics of beta-carotene. Following optical excitation to S(2) (1B(u) (+)) the molecule relaxes in 160 fs to S(1) (2A(g) (-)) and then undergoes two distinct stages of intramolecular vibrational energy redistribution (IVR) with 200 and 450 fs time constants. These processes are attributed to rapid (200 fs) distribution of the internal conversion energy from the S(1) C=C modes into a restricted bath of anharmonically coupled modes followed by complete IVR in 450 fs. FSRS is a valuable new technique for studying the vibrational structure of chemical reaction intermediates and transition states.
A multiscattering series for impedance tomography in layered media

We introduce an inversion algorithm for tomographic images of layered media. The algorithm is based on a multiscattering series expansion of the Green function that, unlike the Born series, converges unconditionally. Our inversion algorithm obtains images of the medium that improves iteratively as we use more and more terms in the multiscattering series. We present the derivation of the multiscattering series, formulate the inversion algorithm and demonstrate its performance through numerical experiments.
Use of PRA and Safety Goals in Nuclear Power Plant Regulation

Probabilistic risk assessments (PRAs) have been performed on a number of nuclear power plants, both by the NRC and industry. The NRC has used risk perspectives gained from PRAs, both in an absolute as well as a relative sense, as an aid in making decisions on plant-specific as well as generic safety issues. However, substantial uncertainties pervade present-day risk assessments, which makes the application of the results of such analyses difficult at best in the regulation of nuclear power. Nonetheless, the Commission approved in January 1983 a policy statement on safety goals for public comment and a two year evaluation period. These safety goals include quantitative design objectives which could serve in the future as risk benchmarks for use by the NRC as part of the decision making process on matters relating to nuclear safety. While the Commission's policy statement explicitly excludes the safety goals from use both in licensing cases and in regulation for the two year evaluation period, PRA will be used generically and on a plant-specific basis more and more to assess the importance of new safety issues, prioritize resources within the agency, and test the adequacy of (or in some instances the need for) NRC's regulations.
Non-Asthmatic Children Have Higher IgM Anti-Enterovirus 71 and Lower IgE Levels, but Higher IL-2 and IL-4 Levels Than Asthmatic Children

S U N D A Y 361 The Association Between Vitamin D Insufficiency and Children with Asthma Ji Tae Choung, MD, Yu-Ri Kim, Sungchul Seo, Young Yoo, MD, PhD; The Environmental Health Center for Asthma; Korea Univ. Medical Center, Seoul, Department of Biochemistry and Molecular Biology, Korea University Medical School & College, Korea, Seoul, The Enviornmental Health Center for Asthma, Korea University, Seoul, Department of Pediatrics, College of Medicine, Korea University, Seoul, South Korea. RATIONALE: Recent epidemiologic studies have shown that the lack of vitamin D levels may be associated with higher asthma prevalence. However, little clinical evaluation was performed in Korea. This study aimed to explore the association of vitamin D levels in serum with asthmatic children in Korea. METHODS: A total of 64 children (34 asthmatic children and 30 healthy children) aged 6-14 years were recruited. Serum 25-hydroxy vitamin D3 (25-OH vitamin D) levels were measured and compared between the both groups. Pulmonary function tests (PFT) as well as questionnaire survey including time of outdoor activity were performed as well. The relationship between serum 25-OH vitamin D levels and the results of PFT as well as time of outdoor activity were examined in asthmatic patients. RESULTS: Serum 25-OH vitamin D levels in asthmatic patients (16.66 4.2 ng/ml) were significantly lower than that in healthy controls (24.2 6 6.8 ng/ml) (P<0.05). Also, about 0.8 times increase of the asthma prevalence was observed as 1 ng/ml of vitamin D level decreased (OR, 0.788; 95% CI, 0.707-0.879; P<0.001). The level of vitamin D for the group with greater than 1 hour of outdoor activity (20.5 ng/ml) was higher than that for group with less outdoor activity (18.0 ng/ml), but no significance was found. There were also no associations with vitamin D level and the results of PFT. CONCLUSIONS: Our findings suggest that the levels of serum vitamin D may be one of risk factors for development or exacerbation of symptoms in children with asthma in Korea.
Liquid formulation of pentoxifylline is a poorly tolerated treatment for Duchenne dystrophy

Objective To perform an open label, pilot study of an orally administered liquid formulation of immediate release pentoxifylline (PTX) to patients with Duchenne muscular dystrophy (DMD). Treatment efficacy, safety and tolerability were assessed.
Effect of a deicing fluid on the durability of carbon/epoxy composites

The degradation of mechanical properties and the moisture absorption of a carbon/epoxy composite is studied through immersion of specimens in two common types of glycol-based (corn-based and synthetic) deicing fluids at two temperatures. Test results indicate that the effects of the fluids are similar at room temperature, while at elevated temperatures, the specimens immersed in the corn-based deicing fluid show a greater drop in the tensile strength. Moreover, gravimetric analysis results show a mass gain in all specimens, with a significantly lower gain from the corn-based deicing fluid than from the synthetic one at the two temperatures selected in this study.
The Influence of Unit Pacing and Mastery Learning Strategies on the Acquisition of Higher Order Intellectual Skills

AbstractThis investigation was undertaken to determine if the acquisition of higher order intellectual processes is tenable for secondary level teaching candidates when the independent variables are unit pacing and different remediation strategies for mastery learning.Significant F ratios resulted for both independent variables and their interaction. The results of this investigation indicate that the remediation strategy which specifies in detail how to correct deficiencies appears to be most appropriate for less intense pacing, while less specific remediations are appropriate for time-compressed programs.
Role of the Bacteriophage T7 and T4 Single-stranded DNA-binding Proteins in the Formation of Joint Molecules and DNA Helicase-catalyzed Polar Branch Migration *

Bacteriophage T7 gene 2.5 single-stranded DNA-binding protein and gene 4 DNA helicase together promote pairing of two homologous DNA molecules and subsequent polar branch migration (Kong, D., and Richardson, C. C. (1996) EMBO J. 15, 2010-2019). In this report, we show that gene 2.5 protein is not required for the initiation or propagation of strand transfer once a joint molecule has been formed between the two DNA partners, a reaction that is mediated by the gene 2.5 protein alone. A mutant gene 2.5 protein, gene 2.5-Delta21C protein, lacking 21 amino acid residues at its C terminus, cannot physically interact with gene 4 protein. Although it does bind to single-stranded DNA and promote the formation of joint molecule via homologous base pairing, subsequent strand transfer by gene 4 helicase is inhibited by the presence of the gene 2.5-Delta21C protein. Bacteriophage T4 gene 32 protein likewise inhibits T7 gene 4 protein-mediated strand transfer, whereas Escherichia coli single-stranded DNA-binding protein does not. The 63-kDa gene 4 protein of phage T7 is also a DNA primase in that it catalyzes the synthesis of oligonucleotides at specific sequences during translocation on single-stranded DNA. We find that neither the rate nor extent of strand transfer is significantly affected by concurrent primer synthesis. The bacteriophage T4 gene 41 helicase has been shown to catalyze polar branch migration after the T4 gene 59 helicase assembly protein loads the helicase onto joint molecules formed by the T4 UvsX and gene 32 proteins (Salinas, F., and Kodadek, T. (1995) Cell 82, 111-119). We find that gene 32 protein alone forms joint molecules between partially single-stranded homologous DNA partners and that subsequent branch migration requires this single-stranded DNA-binding protein in addition to the gene 41 helicase and the gene 59 helicase assembly protein. Similar to the strand transfer reaction, strand displacement DNA synthesis catalyzed by T4 DNA polymerase also requires the presence of gene 32 protein in addition to the gene 41 and 59 proteins.
Between predication and silence : Augustine on how (not) to speak of God

Throughout his corpus (both theological and pastoral), Augustine grapples with the challenge of how (not) to speak of that which exceeds and resists conceptualization. The one who would speak of God is confronted, it seems, by a double-bind: either one reduces God's transcendence to the immanence of language and concepts, or one remains silent. Even to call God ‘inexpressible’, he remarks in De doctrina christiana, is to predicate something of God and thus make some claim to comprehension. ‘This battle of words’, he continues, ‘should be avoided by keeping silent’ (DC 1.6.6). Augustine thus seems to privilege and apophatic strategy. But this is not his last word on the matter. Indeed upon the heels of this passage he carefully notes: ‘And yet, while nothing really worthy of God can be said about him, he has accepted the homage of human voices, and has wished us to rejoice in praising [laude] him with our words.’ My goal in this essay is to consider Augustine's laudatory strategy of ‘praise’ as a non-objectifying discourse concerning transcendence which navigates the straits between kataphatic theological positivism and apophatic silence. This will be taken up against the horizon of contemporary discussions of transcendence and phenomenology, particularly in the work of Jacques Derrida and Jean-Luc Marion.
Robust contact modeling using trimmed NURBS surfaces for dynamic simulations of articular contact

Computational simulation of the behavior of orthopaedic implants in a realistic in vivo environment is rapidly growing in importance as a test applied to prospective designs as younger patients place greater functional demands on their new joints. In addition to muscle and ligament forces, forces caused by implant contact must be computed and applied in an accurate and efficient manner during these simulations. A method is presented by which implant contact forces are computed from the contact nodes on one implant as the nodes penetrate into NURBS surface patches that comprise a second implant using a rigid-body-spring-model (RBSM). A scheme for placing evenly-distributed contact nodes is described, as well as methods for unambiguously interpreting whether a node is in contact with a specific surface. The ability to represent the surface properly was then evaluated using various spring-spacings. Spacing contact nodes 3 mm apart using this scheme appears to produce simulated implant motions that are similar to those obtained using smaller spacings, and results in simulations that are more stable than those possible when a similar number of spring nodes are placed using triangulation.
Open Access Journals in College Library Collections

Students and scholars can take full advantage of Open Access journals only if libraries make them available through mechanisms that are familiar to patrons. This study examines the extent to which American liberal arts colleges have provided access to Open Access journals through their journal title lists (Serials Solutions, Ex Libris, etc.) and their online public access catalogs (OPACs). While 57 percent of the colleges provide access to at least 90 percent of the journals in our sample, 20 percent of the colleges provide access to fewer than 20 percent of the journals. Large and high-impact journals are especially likely to appear in libraries' catalogs and journal lists. There is no systematic trend by publication fee status or country of publication, however. The study concludes with a discussion of the strategies libraries can use to select Open Access journals and add them to their collections.
Influence of oxygen concentration on the sooting behavior of ethanol droplet flames in microgravity conditions

Abstract The influence of oxygen (O 2 ) concentration and inert on the sooting and burning behavior of large ethanol droplets under microgravity conditions was investigated through measurements of burning rate, flame temperature, sootshell diameter, and soot volume fraction. The experiments were performed at the NASA Glenn Research Center (GRC) 2.2 s drop tower in Cleveland, OH. Argon (Ar), helium (He), and nitrogen (N 2 ) were used as the inerts and the O 2 concentration was varied between 21% and 50% mole fraction at 2.4 atm. The unique configuration of spherically symmetric droplet flames enables effective control of sooting over a wide range of residence time of fuel vapor transport, flame temperature, and regimes of sooting to investigate attendant influences on burning behavior of droplets. For all inert cases, soot volume fraction initially increased as a function of the O 2 concentration. The highest soot volume fractions were measured for experiments in Ar environments and the lowest soot volume fractions were measured for the He environments. These differences were attributed to the changes in the residence time for fuel vapor transport and the flame temperature. For the He inert and N 2 inert cases, the soot volume fraction began to decrease after reaching a maximum value. The competition between the influence of residence time, rate of pyrolysis reactions, and soot oxidation can lead to this interesting behavior in which the soot volume fraction varies non-monotonically with increase in O 2 concentration. These experiments have developed new understanding of the burning and sooting behaviors of ethanol droplets under various O 2 concentrations and inert substitutions.
Enhanced Sequential Flushing Process for Removal of Mixed Contaminants from Soils

The feasibility of a sequentially enhanced process for the remediation of soils contaminated by mixed contaminants, specifically multiple polycyclic aromatic hydrocarbons (PAHs) and heavy metals, was investigated. This process consists of sequential flushing using two chemical agents: a surfactant and a chelate. A series of laboratory column experiments was conducted with three different sequential schemes, designated as SEQ1, SEQ2, and SEQ3, in two distinct flushing stages, to remove PAHs and heavy metals from a field-contaminated soil. The SEQ1 scheme involved flushing 0.2 M ethylenediaminetetraacetic acid (EDTA) followed by flushing 5 % Igepal. The SEQ2 scheme involved flushing 5 % Igepal followed by flushing 0.2 M EDTA. SEQ1 was investigated under a constant hydraulic gradient of 1.2, while the SEQ2 scheme was investigated under hydraulic gradients that increased from 1.2 to 4.0. The SEQ3 scheme consisted of sequential flushing of 5 % Igepal (first stage) and 0.2 M EDTA (second stage) under a constant low hydraulic gradient of 0.2. The selected sequential schemes allowed an assessment of the efficacy of sequencing the surfactant and chelating flushing for the removal of multiple heavy metals and PAHs under various hydraulic gradients. The hydraulic conductivity (or flow) was found to vary depending on the flushing agent and the sequence scheme. Under the high hydraulic gradient, the hydraulic conductivity was lower during chelant flushing stage as compared with surfactant flushing stage in both SEQ1 and SEQ2. However, under a low gradient condition (SEQ3), the hydraulic conductivity was approximately the same during both chelant and surfactant flushing stages. The contaminant removal was also significantly affected by the flushing agent and sequence and the applied hydraulic gradient. Heavy metals were removed during chelant flushing, while PAHs were removed during surfactant flushing. The total removal efficiencies of Pb, Zn, and Cu were 76 %, 63 %, and 11 % in SEQ1 and 42 %, 40 %, and 7 % in SEQ2, respectively, while the total removal efficiencies of phenanthrene, anthracene, benz(a)anthracene, and pyrene were 51 %, 35 %, 58 %, and 39 % in SEQ1 and 69 %, 50 %, 65 %, and 69 % in SEQ2, respectively. Overall, the total mass removal of heavy metals and PAHs was higher in SEQ1 as compared with SEQ2, demonstrating that SEQ1 is the effective sequence scheme. Comparison of the results of high and low gradient conditions (SEQ2 and SEQ3) reveals that the removal of contaminants, especially heavy metals, is rate-limited. Overall, this study showed that the removal of co-existing heavy metals and PAHs from soils is possible through the careful selection of the sequence under which the flushing of chelant and surfactant occurs and depends on the site-specific soil and contaminant conditions. Additional research is needed to establish the most optimal flushing scheme (sequence duration and flow velocity) to remove the mixed contaminants effectively and efficiently.
Methods for studying treefall gaps: A review

As silvicultural objectives have changed over the last several decades, managers are increasingly designing cutting regimes that mimic natural disturbance with the hopes that such systems will restore forests to a more natural condition while optimizing harvest yield. Treefall gaps, canopy openings caused by the death of one or more trees, are the dominant form of disturbance in many forest systems worldwide. These gaps play an important role in forest ecology by helping to maintain bio- and pedo-diversity, influencing nutrient cycling, and preserving the uneven-age nature of late-successional forests. In gap literature, there are inconsistencies with regard to gap terminology, methods for identifying and studying gaps, and modeling gap disturbances. From the papers reviewed, the size of treefall gaps ranges widely from 10 to >5000 m 2 ; we suggest that the maximum gap size should be set at 1000 m
Separating parsing and analysis in reverse engineering tools

The authors describe the lessons learned in extending the capabilities of a reverse engineering tool to analyze both an additional dialect of the language it was initially built to parse and a new embedded assembly language. The effort involved in this extension provides data to support the assertion that reverse engineering tools should create a clean separation between parsing the source code and analyzing it. A language independent modeling approach is discussed that will allow achieving this separation. Additional advantages that accrue by maintaining this separation, such as multiple language support and support for design recovery, are discussed. >
Construction and characterization of a soybean yeast artificial chromosome library and identification of clones for the Rps6 region

We report the construction and characterization of the first soybean yeast artificial chromosome (YAC) library using high-molecular weight DNA isolated from leaf nuclei of the cultivar Conrad 94 that carries Phytophthora resistance genes Rps1-k and Rps6. The quality of this library has been evaluated through analysis of 393 randomly selected YAC clones. The library consists of 36,864 clones, of which � 19,956 carry single soybean YACs with an average size of about 285 kb. The library represents approximately five soybean genome equivalents. The probability of finding any soybean sequences from this library is about 0.99. The library was screened for 43 SSR markers representing the whole soybean genome. We were able to identify positive YAC pools for 95% of the SSR markers. Two YAC clones carrying molecular markers linked to the Rps6 gene were identified. The YAC library reported here would be a useful resource for map-based cloning of agronomically important soybean genes and also to complement the effort towards construction of the physical map for the soybean genome.
Origin of Non-Gaussian Regimes and Predictability in an Atmospheric Model

AbstractThis study details properties of non-Gaussian regimes and state-dependent ensemble spreads of trajectories in a reduced phase space of an idealized three-level quasigeostrophic (QG3) dynamical model. Methodologically, experiments using two empirical stochastic models of the QG3 time series disentangle the causes of state-dependent persistence properties and nonuniform self-forecast skill of the QG3 model. One reduced model is a standard linear inverse model (LIM) forced by state-independent, additive noise. This model has a linear deterministic operator resulting in a phase-space velocity field with uniform divergence. The other, more general nonlinear stochastic model (NSM) includes a nonlinear propagator and is driven by state-dependent, multiplicative noise. This NSM is found to capture well the full QG3 model trajectory behavior in the reduced phase space, including the non-Gaussian features of the QG3 probability density function and phase-space distribution of the trajectory spreading rates....
Interdisciplinary Social Studies and Science Lessons with a Native American Theme

(1996). Interdisciplinary Social Studies and Science Lessons with a Native American Theme. The Social Studies: Vol. 87, No. 2, pp. 72-77.