cssi/SciSciGPT-SciSciNet huggingface dataset:
A phenomenological approach to the superconducting transition in thin films and S-N superlattices

Abstract A simple phenomenological approach is described for the superconducting transition in thin films and S-N superlattice structures. The principal ingredients in an approach based on the Ginzburg-Landau free energy are (a) a pairbreaking energy at the surface (or interface) and (b) a proximity-induced free energy for the order parameter in the normal phase. The shift in T c is found to be inversely proportional to the superconductor thickness in a moderate range of thicknesses.
Using the relationship between geometry and hyperpolarizability as a tool for developing new paradigms for molecular engineering

We consider how geometry and symmetry alone play a role in determining the magnitude of the hyperpolarizability. Using potential energy functions given by a superposition of force centers representing nuclei, we find that for certain specific geometries, such as asymmetric octupolar-like molecule with donors and acceptors of varying strengths at the branches, the hyperpolarizability is near the fundamental limit. The fact that the hyperpolarizability, when it is at the fundamental limit, is well approximated by a three-level model confirms the three-level ansatz. Our results suggest new design strategies for breaking beyond the apparent limit.
High power fiber optic parametric amplifier at 1 μm wavelength based on a large area high order mode

We demonstrate parametric amplification at 1.064 μm with a 600 μm2 fiber mode, with 94 nm gain bandwidth, cascade products over 315 nm bandwidth, and 6 kW peak power in the Stokes and anti-Stokes lines.
Amplitude-integrated Electroencephalography: A New Approach to Enhancing Neurologic Nursing Care in the Neonatal Intensive Care Unit☆

Abstract Critically ill infants are at higher risk for developing adverse neurodevelopmental outcomes because of their physiologic and neurologic vulnerabilities, complex medical treatment, and stressful neonatal intensive care unit (NICU) environment. Continuous monitoring of brain function serves to evaluate medical and nursing interventions, detect early signs of alteration in brain function, and thus may improve long-term neurologic outcomes. Amplitude-integrated electroencephalography is a limited-channel electroencephalography that provides a noninvasive method for continuous observation of cerebral background activity at the bedside. Amplitude-integrated electroencephalography is increasingly being used in the NICU. Varied clinical and research applications for the neonatal population make up a growing body of knowledge. Amplitude-integrated electroencephalography has the potential to enhance the ability of nurses to provide targeted neurodevelopmental care in the NICU.
Interactions of Full-Length Synaptotagmin 1 with Ca2+ and Membrane Surfaces

Synaptotagmin 1 (Syt1) is a synaptic vesicle-anchored membrane protein that acts as the major calcium sensor for the regulated neuronal exocytosis. A soluble fragment of Syt1, which has the two cytoplasmic C2 domains but lacks the transmembrane domain, has been the subject of extensive studies and is believed to mimic the main functions of Syt1. However detailed conformational studies of the full-length Syt1 during the triggering of membrane fusion and the mechanisms involved in the regulation by the full-length Syt1 has not been reported. Here we employed EPR spectroscopy and signal molecule fluorescence spectroscopy to investigate the vesicle-anchored full-length Syt1 structure regulated by Ca2+ in the presence of key membrane lipids, such as PS and PIP2. CW-EPR lineshapes from the region linking the transmembrane domain to the first C2 domain indicate that the juxtamembrane region has some secondary structure or is membrane associated. Power saturation of the spectra indicate that most of this linker is located between membrane interface and the lipid head-group region, and double electron-electron resonance (DEER) measurements of single spin-labeled Syt1 mutants indicate that Syt1 tends to form dimers or small clusters. The structure of full-length Syt1 is also being probed on supported bilayers using fluorescence interference contrast microscopy (FLIC) to determine the position of the linker region and the position of the C2 domains under conditions where binding to a second bilayer surface takes place.
Synthesis of 9-fluorenemethyl boranophosphonodiphosphate via an H-phosphonate approach.

9-Fluorenemethyl boranophosphonate 6 and its boranophosphonodiphosphate 7 were synthesized via an H-phosphonate approach. The method is efficient for the synthesis of acyclic compounds 6 & 7 , and can be explored for the synthesis of nucleoside 5′-deoxy boranophosphonodiphosphate.
De Novo Non-Alcoholic Fatty Liver Disease Following Orthotopic Liver Transplantation

Non-alcoholic fatty liver disease (NAFLD) is an increasingly recognized clinico-pathologic entity typically associated with obesity, type II diabetes and hyperlipidemia. It has been noted to recur after orthotopic liver transplantation (OLT). We report four patients who developed de novo NAFLD within 3 months of OLT without the typical predisposing factors of diabetes mellitus or obesity. Three of the four patients underwent OLT for hepatitis C-related cirrhosis, and the other for alcoholic cirrhosis. Examination of the liver explants revealed no evidence of steatosis. No surreptitious alcohol use or a drug-induced process could be identified in these patients. Treatment of recurrent hepatitis C infection in one patient with interferon and ribavirin led to sustained suppression of the viral RNA to undetectable levels, but no improvement in histology or liver enzymes. All four patients had histologic evidence of preservation injury on the initial post-OLT biopsies, but the significance of this finding in relationship to the development of NAFLD is unknown. NAFLD can develop without any of the known predisposing conditions after transplantation, and this raises further questions about the pathogenesis of this condition.
A central negative feedback action of thyroid hormones on thyrotropin-releasing hormone secretion.

Two experiments were conducted to test the hypothesis that thyroid hormones exert central negative feedback effects on the secretion of TRH from the hypothalamus in the ewe. In the first experiment, we examined the effects of thyroidectomy on the secretion of TRH and TSH. Thyroidectomy was followed by an unambiguous increase in TRH in pituitary portal plasma and TSH in the peripheral circulation. In the second experiment, we tested the effects of T4 replacement to thyroidectomized ewes. T4 replacement reversed the effects of thyroidectomy on TRH and TSH release. Of interest, TRH secretion in thyroidectomized ewes was continuously elevated during the collection, raising the possibility that TRH is secreted continuously, rather than exclusively in a strictly pulsatile manner indicative of phasic discharges synchronized among TRH neurosecretory elements. Collectively, these results suggest that thyroid hormones can act centrally to inhibit TRH (and thus TSH) release in the ewe, and they support the concept t...
Reproductive and sexual health in males with cystic fibrosis: a case for health professional education and training

Abstract Purpose: To survey the attitudes and clinical practice of health professionals to identify current practice and possible barriers to discussion of sexual and reproductive health issues in adolescent males with cystic fibrosis (CF). Methods: An interview schedule was developed to seek information about attitudes to reproductive and sexual health in males with CF and to elicit details of reported professional practice of health care providers from four CF centers in Massachusetts. Results: Of 32 health professionals interviewed, 66% informed parents about male infertility soon after diagnosis in infancy; 22% of those not informing parents at this time waited until later childhood or adolescence; and 12% reported they did not discuss these issues with parents during childhood or adolescence. All respondents reported they discuss infertility with male adolescents. The mean age thought most appropriate to discuss infertility was 13.8 (±2.2) years, although most do so at 15.2 (±2.8) years ( p Conclusions: Greater training for health professionals in the reproductive and sexual health issues of CF is a step to more complete, timely, and comfortable discussion of this area of health care.
Electrochemical Self-Assembly of Monolayers from Alkylthiosulfates on Gold

Selective preparation of self-assembled monolayers (SAMs) on gold was accomplished by electrolysis of alkylthiosulfates (Bunte salts) in tetrahydrofuran in the presence of tetrabutylammonium tetrafluoroborate as the supporting electrolyte. Tetrafluoroborate ions inhibited the spontaneous chemisorption of alkylthiosulfates to form monolayers, so that monolayers formed only on gold electrodes at a sufficiently oxidative potential. This oxidative potential was applied using square-wave pulses, and as expected, the degree of completeness of the monolayers depended upon both the voltage and the period during which it was applied. Using this method, monolayers could be formed quickly, in only twenty 5-s pulses. X-ray photoelectron spectroscopy and infrared spectroscopy supported our hypothesis that this process involves formation of stable gold−thiolate bonds at the gold surface and that (bi)sulfate is a side-product under our experimental conditions. Unlike the preparation of SAMs from alkanethiols, clean gold...
Last Season of Innocence: The Teen Experience in the 1960s. By Victor Brooks. (Lanham, MD: Rowman & Littlefield, 2012. Pp. vi, 205. $35.00.)

In a Proustian moment from a 2001 episode of “The Simpsons,” Homer bites into an animal cracker that he knows was made in the 1960s. “Mmm!” he exclaims, “Turbulent!” But Homer is wrong. The animal ...
Co-Teaching: A Simple Solution That Isn't Simple After All

Among the many programs that professional educators are developing to better help their increasingly diverse students reach their potential, co-teaching is emerging as an innovative and potentially effective approach. As a way to ensure that students with disabilities or other special needs have access to the same curriculum as other students and the opportunity to succeed in the general education setting, co-teaching occurs when two professionals, typically a general education teacher and a special education teacher or another specialist, partner in delivering instruction. Although the research base on co-teaching is still emerging, it suggests that co-teaching is far more complex to effectively implement than it might seem at first consideration. Challenges to co-teaching that have been identified and must be addressed include: arranging time for co-planning, building positive working relationships between co-teaching partners, clarifying roles and responsibilities, and ensuring administrative support. When creative strategies for arranging common planning time, building understanding and collaboration between co-teachers, planning and delivering instruction, and enlisting principal and other administrative supports are implemented, the potential of co-teaching for improving student outcomes is significant.
Alphabet Soup: Blurring the Distinctions Betweenp’s anda’s in Psychological Research

Confusion over the reporting and interpretation of results of commonly employed classical statistical tests is recorded in a sample of 1,645 papers from 12 psychology journals for the period 1990 t...
Current programmed control nonresonant coupled parallel resonant convertor

In the nonresonant coupled parallel resonant convertor operated below unity gain, the inductor current at the switching points has a maximum value which is determined by the convertor gain and the output load. By switching transistors at predetermined inductor current levels, it is possible to regulate the output voltage due to output current and input voltage variations. The peak inductor current, which can be limited to desirable values, is regulated by the control circuit. By using nonresonant coupling in the output circuit, the maximum capacitor voltage is clamped to the output voltage level; thus, the convertor has low voltage stresses. In the paper, the authors introduce the analysis and design of this convertor. The performance characteristics of the convertor are also presented. Computer simulation results are used to verify the authors' theoretical work. >
Dimensions of Aesthetic Perception.

Summary Researchers working in experimental aesthetics have identified three dimensions of aesthetic perception: Hedonic Value, Arousal, and Uncertainty. The primary purpose of the present study was to examine the validity of these dimensions. Twelve paintings were rated by the 46 subjects on 12 adjective scales and the ratings were subjected to factor analyses. Results suggested that interestingness, powerfulness, and complexity may be more highly associated with the Hedonic Value factor than previously recognized, while the Arousal factor may be more highly associated with judgments of displeasingness and ugliness. The Uncertainty factor here derived is highly similar in structure to that reported in previous research.
Substrate specificity of muscle aldolase.

A study of the substrate specificity of rabbit muscle aldolase led to the following observations. 1. 1. Both the d and l isomers of glyceraldehyde-3-phosphate can be condensed with dihydroxylacetone phospahte, but the former appears to react much more rapidly than the latter. 2. 2. Tagatose-i, 6-diphosphate, which possesses a cis configuration of hydroxyl groups on carbon atoms 3 and 4, is cleaved but at a slower rate than d-fructose-i, 6-diphosphate or l-sorbose-i, 6-diphosphate. 3. 3. The condensation of d- or l-glyceraldehyde with dihydroxyacetone phosphate to yield fructose- or sorbose-i-phosphates respectively is reversible. Crystalline rabbit muscle aldolase has a much greater affinity for fructose diphosphate (KM = 5·10−5M) than for fructose-i-phosphats (KM = 3.4 · 10−3M).
Effects of pharmacologic hyperglucagonemia on plasma amino acid concentrations in normal and diabetic man

Four normal and five insulin dependent diabetic men received a 2 h pharmacologic glucagon infusion (50 ng/kg/min) resulting in plasma glucagon levels (4400 pg/ml) similar to those seen in glucagonoma patients. In normal subjects in whom plasma insulin concentrations rose significantly (239 uU/ml) and the blood level of 15 of the 18 amino acids measured fell significantly. In contrast, in the diabetic men who secreted no insulin in response to glucagon (no rise in C-peptide levels), only 10 of 18 amino acid levels fell significantly. The branched chain amino acids valine, leucine and isoleucine, as well as tyrosine and phenylalanine were among the 8 amino acids which showed no change in response to glucagon in the diabetics. Thus, glucagon appears to have no acute affect on branched chain amino acid levels in man.
Regional collective security in Europe: Past patterns and future prospects

NATO's entry into the Balkan war raised salient questions about the alliance's broader mission and, more generally, about Europe's security architecture. This article confronts these questions by revisiting the debate about collective defense versus collective security as organizing principles for alliances. NATO is viewed as serving a hybrid role of promoting collective defense and regional collective security. This latter, under‐valued function relates to NATO's role in promoting internal cohesion among its members and is crucial to understanding the alliance's evolution and its persistance long after the Cold War.
Integrating Social Justice in Group Work: The Next Decade

Group work can be an effective outlet for facilitating client empowerment at individual and systemic levels. This article outlines strategies for increasing attention to social justice issues in group work over the next decade within education, training, supervision, practice, and research. Drawing from historical perspectives, current literature, and experience as social justice-minded scholars, educators, and practitioners, the authors describe numerous and unique opportunities as well as potential challenges for group workers engaging in social justice advocacy and practice. Topics explored include consciousness raising, group empowerment, community organizing, definitions of social justice, attribution theory, and sociopolitical identity development.
Transforming Growth Factor-β1-Induced Proliferation of the Prostate Cancer Cell Line, TSU-Pr1: The Role of Platelet-Derived Growth Factor

The results of our previous study revealed that transforming growth factor-β1 (TGFβ1) stimulated proliferation of the prostate cancer cell line, TSU-Pr1. This observation is unexpected, for TGFβ usually inhibits proliferation in prostate cancer cells. The present study examines possible mechanisms through which TGFβ1 induces this proliferation. We postulate that TGFβ1 action is mediated through an indirect mechanism by inducing the expression of platelet-derived growth factor (PDGF), which, in turn, stimulates proliferation. The TGFβ1-induced proliferation can be abrogated by treatment with a PDGF-neutralizing antibody. Treatment with exogenous PDGF significantly increased TSU-Pr1 proliferation. Finally, treatment of TSU-Pr1 cells with TGFβ1 resulted in an increase in PDGF secretion. These results indicate that TGFβ1-induced proliferation in TSU-Pr1 cells is at least mediated through an increased secretion of PDGF.
Retinal Periphlebitis as an Early Sign of Bacterial Endophthalmitis

Retinal periphlebitis appeared as an early sign of bacterial endophthalmitis in three patients, a 36-year-old man with bilateral Terson's syndrome who underwent vitrectomy for dense vitreous hemorrhage, a 78-year-old woman who had had intracapsular cataract extraction and penetrating keratoplasty after repair of a wound leak and pars plana anterior membranectomy, and an 18-year-old man who suffered an accidental penetrating ocular injury. Staphylococcus organisms were recovered from vitreous samples in all three cases. Although recovery of useful vision is rare after postvitrectomy endophthalmitis, the first patient attained a final visual acuity of 20/50. The visual acuities of the second and third patients returned to 20/25 and 20/20 respectively. In an experimental primate (cynomolgus monkey) model of bacterial endophthalmitis, retinal periphlebitis developed early and closely resembled the clinical findings in humans. Histopathologic studies confirmed the presence of inflammatory cells that infiltrated the retinal venules.
Bioavailability of Ampicillin and Amoxicillin in Fasted and Nonfasted Subjects

The influence of various test meals and fluid volume on the relative bioavailability of ampicillin and amoxicillin was studied in healthy human subjects. Serum amoxicillin levels were somewhat, but not always, significantly higher than those of ampicillin from equivalent oral doses. Food ingested immediately before dosing reduced serum levels and urinary excretion of both antibiotics to a similar extent. Reduction of dosed water volume caused a marked decrease in serum amoxicillin levels in fasted subjects.
Methionine Sulfoximine, a Glutamine Synthetase Inhibitor, Attenuates Increased Extracellular Potassium Activity during Acute Hyperammonemia

Hyperammonemia causes glutamine accumulation and astrocyte swelling. Inhibition of glutamine synthesis reduces ammonia-induced edema formation and watery swelling in astrocyte processes. Ordinarily, astrocytes tightly control extracellular K+ activity [K+]e. We tested the hypothesis that acute hyperammonemia interferes with this tight regulation such that [K+]e increases and that inhibition of glutamine synthetase reduces this increase in [K+]e. Ion-sensitive microelectrodes were used to measure [K+]e in parietal cortex continuously over a 6-h period in anesthetized rats. After i.v. sodium acetate infusion in eight control rats, plasma ammonia concentration was 33 +/- 26 mumol/L (+/- SD) and [K+]e remained stable at 4.3 +/- 1.6 mmol/L. During ammonium acetate infusion in nine rats, plasma ammonia increased to 594 +/- 124 mumol/L at 2 h and to 628 +/- 135 mumol/L at 6 h. There was a gradual increase in [K+]e from 3.9 +/- 0.7 to 6.8 +/- 2.7 mmol/L at 2 h and 11.8 +/- 6.7 mmol/L at 6 h. In eight rats, L-methionine-D,L-sulfoximine (150 mg/kg) was infused 3 h before ammonium acetate infusion to inhibit glutamine synthetase. At 2 and 6 h of ammonium acetate infusion, plasma ammonia concentration was 727 +/- 228 and 845 +/- 326 mumol/L, and [K+]e was 4.5 +/- 1.9 and 6.1 +/- 3.8 mmol/L, respectively. The [K+]e value at 6 h was significantly less than that obtained with ammonium acetate infusion alone but was not different from that obtained with sodium acetate infusion. We conclude that acute hyperammonemia impairs astrocytic control of [K+]e and that this impairment is linked to glutamine accumulation rather than ammonium ions per se.
A rapid method for extraction of cotton (Gossypium spp.) genomic DNA suitable for RFLP or PCR analysis

Extraction of high-quality genomic DNA fromGossypium (cotton) species is difficult due to high levels of polysaccharide, oxidizable quinones, and other interfering substances. We describe a procedure that consistently permits isolation of cotton genomic DNA of satisfactory size and quality for RFLP and PCR analysis, as well as for most routine cloning applications. Several antioxidants, phenol-binding reagents, and phenol oxidase inhibitors are used throughout the procedure, and most polysaccharides are eliminated early in the procedure by isolation of nuclei.
Some results based on a general stochastic model for mental tests.

There have been a number of important developments by several authors which are based on the assumption that test taking behavior is stochastic. That is, it is assumed that the probability that an individual will "endorse" or "pass" a dichotomous item can be represented by some function of an underlying, "latent" attribute (possibly multivariate) called the item trace line or item characteristic curve. Various forms for trace lines have been postulated such as polynomial [9, 11], step function [9], normal ogive [13, 19], and logistic [1, 2]. An interesting model due to Rasch [18] utilizes only a subject parameter and item parameter to determine the probability of passing an item. The only model which does not make some formal assumptions about trace lines is Lazarsfeld's latent class model. All of these models for test behavior are unified by two basic assumptions. One is the stochastic assumption of a probability of passing or endorsing an item. The probability of passing a specified item may be construed as an attribute of each individual with a given score on the latent attribute, or it may be construed as the proportion passing the item in the class of individuals with a given value on the latent attribute. Lazarsfeld has presented an excellent discussion of this topic [10]. Unfortunately, since these two different postulates usually yield the same results, they cannot be distinguished empirically. On the other hand, the same techniques may be applied without commitment to one or the other assumptions. The other assumption common to this class of models is the assumption of local independence. If the probability of passing an item is construed as an attribute of an individual, the local independence assumption asserts that the probability an individual will pass two or more items in a test is the product of his separate probabilities of passing. If the probability of passing is construed as a proportion of the class of individuals with a given latent attribute score, the local independence assumption asserts that the proportion of the class passing two or more items in a test is the product of the separate proportions passing characteristic of that class. Now if it is assumed that the probability of passing an item is an at-
Current status of theory of transport of ions across membranes

Abstract The status of the actual knowledge on transport across biological membranes is reviewed on the basis of phenomenological and theoretical considerations.
Posttranslational processing of infected cell protein 22 mediated by viral protein kinases is sensitive to amino acid substitutions at distant sites and can be cell-type specific.

Infected cell protein 22 (ICP22) is posttranslationally phosphorylated by the viral kinases encoded by US3 and UL13 and nucleotidylylated by casein kinase II. In rabbit and rodent cells and in primary human fibroblasts infected with mutants from which the α22 gene encoding ICP22 had been deleted, a subset of late (γ2) gene products exemplified by UL38 and US11 proteins are expressed at a reduced level, as measured by the accumulation of both mRNA and protein. The same phenotype was observed in cells infected with mutants lacking the UL13 gene. The focus of this report is on three serine- and threonine-rich domains of ICP22. Two of these domains are homologs located between residues 38 to 66 and 300 to 328. The third domain is near the carboxyl terminus and contains the sequence T374SS. The results were as follows. (i) Alanine substitutions in the amino-terminal homolog precluded the posttranslational processing of ICP22 in rabbit skin cells and in Vero cells but had no effect on the accumulation of either US11 or UL38 protein. (ii) Alanine substitutions in the carboxyl-terminal homolog had no effect on posttranslational processing of ICP22 accumulating in Vero cells but precluded full processing of ICP22 accumulating in rabbit skin cells. The effect on accumulation of UL38 and US11 proteins was insignificant in Vero cells and minimal in rabbit skin cells. (iii) Substitutions of alanine for the threonine and serines in the third domain precluded full processing of ICP22 and caused a reduction of accumulation of US11 and UL38 proteins. These results indicate the following. (i) The posttranslational processing of ICP22 is sensitive to mutations within the domains of ICP22 tested and is cell-type dependent. (ii) Posttranslational processing of ICP22 is not required for accumulation of UL38 and US11 proteins to the same level as that seen in cells infected with the wild-type virus. (iii) The T374SS sequence shared by ICP22 and the US1.5 proteins is essential for the accumulation of a subset of γ2 proteins exemplified by US11 and UL38 and is the first step in mapping of the sequences necessary for optimal accumulation of US11 and UL38 proteins.
Sequences of four mouse histone H3 genes: implications for evolution of mouse histone genes.

The sequences of four histone H3 genes coding for the replication variant proteins H3.1 and H3.2 have been determined. Three of these genes, two coding for H3.1 proteins and one for an H3.2 protein, are located on chromosome 13 and expressed at low levels. The fourth gene, encoding an H3.2 protein, is located on chromosome 3 and expressed at a high level. The coding regions of the three genes on chromosome 13 are more similar to each other than to the H3 gene on chromosome 3, and equally divergent from it, suggesting that either gene duplication or gene conversion has occurred since the genes were dispersed onto two chromosomes. A 14-base sequence including the CCAAT sequence and located 5′ to the genes on chromosome 13 has been conserved. The histone H3 gene on chromosome 3 has multiple potential binding sites for the Sp1 transcription factor. The coding regions show >95% conservation among the four genes. This is due to the strict pattern of codon usage and the presence of two long (>60 base) regions of completely conserved nucleic acid sequence. These conserved regions in the coding sequence may have an important functional role at the mRNA or DNA level.
Improved CO 2 lidar receiver based on ultralow-noise FPA technology

ABSTRACT A high sensitivity, CO2 lidar detector, based on recent advances in ultra-low noise, readout integrated circuits(ROIC), is being developed. This detector will combine a high speed, low noise focal plane array (FPA) with a dispersivegrating spectrometer. The spectrometer will filter the large background flux, thereby reducing the limiting backgroundphoton shot noise. In order to achieve the desired low noise levels, the HgCdTe FPA will be cooled to -5OK. High speed,short pulse operation of the lidar system should enable the detector to operate with the order of a few noise electrons in the combined detector/ROIC output. Current receiver design concepts will be presented, along with their expected noise performance.Keywords: LWIR lidar receiver; focal plane array; ultra-low noise ROTC, HgCdTe infrared detector 1. INTRODUCTION The application of CO2 differential absorption lidar (DIAL) to chemical remote sensing allows extremely sensitivedetection of atmospheric constituents. In the DIAL technique', the transmitted laser pulse propagates through the atmosphereto a hard target and the reflected light is collected by a receiver telescope and focused onto a detector. By tuning the laserfrequency over various laser lines, the spectral variation in absorption "fingerprints" existing chemicals along the laser path.A state-of-the-art DIAL system built at Los Alamos National Laboratory (LANL) presently uses a CO2 laser transmitter and asingle element HgCdTe photovoltaic sensor to measure the magnitude of the backscattered laser pulse. The detectionsensitivity of such DIAL systems, although dependent on many experimental factors, may still be significantly improved byadvancing the technology of basic laser and detector components. Development efforts toward improving the detector arepresented in this paper.In a DIAL sensor, the laser wavelength should be tuned rapidly through a set of chosen spectral lines. Withincertain limits, the faster the lines are tuned, the more shots that can be averaged (in a given time) and the S/N of the sensorwill improve. While being rapidly tuned in wavelength with each shot, the laser output must remain stable, both in mode andin energy. At LANL, a recently demonstrated technique2 uses acousto-optic (AO) technology to tune the laser wavelengthand achieves high pulse repetition frequencies (pro on the order of 5-10 kHz, with no moving parts. On each pulse, the AO"tuner" can select a different laser line and a set of wavelengths can be cycled through at a rate of -
A dyadic shift-invariant spectrum for the discrete cosine transform

The discrete cosine transform (DCT) was introduced in 1974 by Ahmed et al. [l] . It is now widely used for a variety of data compression applications [ 21. In particular, in the area of digital image compression for transmission, it has been accepted as an industry standard [ 3 ] . The main objective of this communication is to introduce a magnitude spectrum for the DCT that is invariant to dyadic shifts of the data sequence. A corresponding phase spectrum is also proposed.
The Community Context of Family Structure and Adolescent Drug Use

Using data from the National Educational Longitudinal Study (NELS), this article investigates a number of hypotheses used to explain the relationship between family structure and adolescent drug use. In particular, using linked community-level data, an explicit examination of hypotheses drawn from a community-context model is conducted. These hypotheses posit that the impact of family structure on adolescent behavior is, in part, explained by the different types of communities within which families reside and that community characteristics moderate the impact of family structure on drug use. The results of multilevel regression models fail to support these hypotheses; adolescents who reside in single-parent or stepparent families are at heightened risk of drug use irrespective of community context. Moreover, adolescents who reside in single father families are at risk of both higher levels of use and increasing use over time. A significant community-level effect involves jobless men: Adolescents are at increased risk of drug use if they reside in communities with a higher proportion of unemployed and out-of-workforce men.
Infrared spectroscopy and thermodynamic measurements of CO on NaCl films

Isotherms of CO on unannealed and annealed NaCl films in the temperature range 83–99 K are reported with an isosteric heat of adsorption of −13±3 kJ mol −1 . Infrared spectroscopy of CO on these films reveals a number of features not reported previously. Analysis of sharp spectroscopic features is consistent with CO adsorption on edges of the film crystallites, on smooth surface faces and on steps. A broad and weak combination band is associated with bending vibrational motions of CO against the surface. Another broad feature suggests absorption of liquid-like CO molecules formed in pores of the film. An analysis of both the thermodynamic and spectroscopic data with an extended Langmuir model of adsorption provides a consistent picture of the binding energy and all the low frequency vibrational motions of CO against its bond to the surface.
The Vaginal Flora of Healthy Women Is Not Always Dominated by Lactobacillus Species

Marrazzos interesting editorial commentary about the "enigmatic ecological mystery" of bacterial vaginosis (BV) fails to take into account the recent findings of several investigations that call into question some long-held assumptions about this disorder. Her essay begins with the pronouncement that we have known for decades that the normal vagina is dominated by hydrogen peroxide-producing lactobacilli and then follows this with the declaration that decreases in the numbers of lactobacilli have been associated with a host of problems including BV gonorrhea HIV infection and cervicitis. However several investigations conducted using cultivation-independent methods have shown that a significant proportion (~30%) of healthy women lack appreciable numbers of Lactobacillus species. (excerpt)
SEMAC: Slice Encoding for Metal Artifact Correction in MRI

Magnetic resonance imaging (MRI) near metallic implants remains an unmet need because of severe artifacts, which mainly stem from large metal-induced field inhomogeneities. This work addresses MRI near metallic implants with an innovative imaging technique called "Slice Encoding for Metal Artifact Correction" (SEMAC). The SEMAC technique corrects metal artifacts via robust encoding of each excited slice against metal-induced field inhomogeneities. The robust slice encoding is achieved by extending a view-angle-tilting (VAT) spin-echo sequence with additional z-phase encoding. Although the VAT compensation gradient suppresses most in-plane distortions, the z-phase encoding fully resolves distorted excitation profiles that cause through-plane distortions. By positioning all spins in a region-of-interest to their actual spatial locations, the through-plane distortions can be corrected by summing up the resolved spins in each voxel. The SEMAC technique does not require additional hardware and can be deployed to the large installed base of whole-body MRI systems. The efficacy of the SEMAC technique in eliminating metal-induced distortions with feasible scan times is validated in phantom and in vivo spine and knee studies.
Monitoring wound healing of venous stasis leg ulcers by in vivo 31P magnetic resonance spectroscopy

Background/aims: Venous stasis ulcers is a frequent clinical problem. Objective techniques for characterization and monitoring of wound healing are needed including noninvasive study of biochemical changes associated with the healing process. 31P magnetic resonance spectroscopy was not used in the past to study human wound healing in vivo. Methods: 31P magnetic resonance spectroscopy with study of intracellular pH, phosphocreatine, and the phosphocreatine/inor-ganic phosphate ratio was used. Six patients with venous leg ulcer and three controls were studied. Results: Both intracellular pH, phosphocreatine and the phos-phocreatine/inorganic phosphate ratio were found sensitive indicators of wound healing. Surprisingly the intracellular pH in healing ulcers was in the alkali range. Conclusion: 31P magnetic resonance spectroscopy was found useful for the study of biochemical changes associated with wound healing. pH in the alkali range was an unexpected observation.
STRUCTURAL AND PARAMETRIC SENSITIVITY OF “UCKRON-1” TEST PROBLEM

Abstract The sensitivity of a specified tabular reactor to thermal runaway is simulated using a model for the UCKRON-1 Test Problem. Parametric sensitivity was increased by the increase of coolant temperature and by the increase of inlet temperature and pressure. Extension of the Test Problem by the water-gas shift reaction reduced the productivity and sensitivity of the reactor. Addition of the water-gas reaction represents the sensitivity for runaway to the structure of the model. These observations lead to a strategy for maximizing the methanol production within a range where thermal runaway does not occur.
The Ranking Probability Approach and Its Usage in Design and Analysis of Large-Scale Studies

In experiments with many statistical tests there is need to balance type I and type II error rates while taking multiplicity into account. In the traditional approach, the nominal -level such as 0.05 is adjusted by the number of tests, , i.e., as 0.05/. Assuming that some proportion of tests represent “true signals”, that is, originate from a scenario where the null hypothesis is false, power depends on the number of true signals and the respective distribution of effect sizes. One way to define power is for it to be the probability of making at least one correct rejection at the assumed -level. We advocate an alternative way of establishing how “well-powered” a study is. In our approach, useful for studies with multiple tests, the ranking probability is controlled, defined as the probability of making at least correct rejections while rejecting hypotheses with smallest P-values. The two approaches are statistically related. Probability that the smallest P-value is a true signal (i.e., ) is equal to the power at the level , to an excellent approximation. Ranking probabilities are also related to the false discovery rate and to the Bayesian posterior probability of the null hypothesis. We study properties of our approach when the effect size distribution is replaced for convenience by a single “typical” value taken to be the mean of the underlying distribution. We conclude that its performance is often satisfactory under this simplification; however, substantial imprecision is to be expected when is very large and is small. Precision is largely restored when three values with the respective abundances are used instead of a single typical effect size value.
Microbial contamination of hospital bed handsets.

Background Hospital bed handsets, including nurse call equipment and television controls, have been found to contain biologic material and may be contaminated with microbes. Objective The aim of this study was to assess the microbial contamination of hospital bed handsets. Methods Hospital bed handsets were removed from 115 randomly chosen rooms in a suburban hospital. The handsets were transported to the laboratory in a sterile fashion and opened using a sterile technique, and cultures were obtained from both the anterior and posterior surfaces of the units. Results The cultures of 12 units (10.4%) revealed no microorganisms. One hundred three units (89.6%) had cultures that grew microorganisms. Of the handsets that were found to contain microorganisms, 48 units (46.6%) had only 1 microorganism, and 55 units (53.4%) had multiple organisms, including 33 units (32.0%) with 2 microorganisms, 21 units (20.4%) with 3 microorganisms, and 1 unit (1.0%) with 4 microorganisms. The microorganisms identified included 90 isolates (87.4%) of coagulase-negative staphylococcus, 51 isolates (49.5%) of bacillus species, 13 isolates (12.6%) of fungal species, 8 isolates (7.8%) of nonhemolytic streptococcus species, 7 isolates (6.8%) of α-hemolytic streptococcus species, 1 isolate (1.0%) of Staphylococcus aureus , and 1 isolate (1.0%) of methicillin-resistant Staphylococcus aureus . Conclusion Hospital bed handsets were found to have a high incidence of contamination with bacteria and fungus and were found to contain organisms that are known to be the etiologic agents in nosocomial infections. Because of the frequency and duration of contact between hospital patients and hospital bed handsets, existing infection control measures should be studied that could reduce the level of contamination of such handsets or that could isolate the handsets from the patient.
Normal 24-hr ambulatory esophageal pH values. Influence of study center, pH electrode, age, and gender.

Although the most sensitive and specific test for diagnosing gastroesophageal reflux disease, normal standards for prolonged esophageal pH monitoring are based on small sample sizes with questions raised about the effects of pH electrode, older age, gender, and methods of data analysis on pH variables. Recently three groups have established normal data bases using similar methodology. Multiple regression and nonparametric analyses showed that the values for the six traditional pH parameters were comparable across study centers. Therefore, the groups were combined for a total study population of 110 healthy subjects (47 men, 63 women, mean age 38 years with a range of 20–84 years). Further nonparametric analyses revealed the following: (1) type of pH electrode (antimony vs glass) is not significantly related to parameters of physiologic acid reflux; (2) age is not independently related to pH parameters; (3) men tend to have more physiologic reflux than women; and (4) older men tend to experience longer episodes of reflux than younger men and women. There was a significant effect of gender and a significant interaction between age and gender on the number of episodes >5 min (P=0.008). Nearly significant differences were found for percentage of total acid exposure time (P=0.03), total reflux episodes (P=0.02), and the longest reflux episode (P=0.02). We believe these normal esophageal pH values can be used confidently as standards in any laboratory, and consideration should be given to developing separate standards for men and women.
The Cooperative Convective Precipitation Experiment (CCOPE), 18 May-7 August 1981.

Abstract The Cooperative Convective Precipitation Experiment, CCOPE, was an outgrowth of the perceived need for more comprehensive data sets on convective clouds. It was planned and executed by a large group of participants, with the leadership of the Convective Storms Division of NCAR and the Office of Atmospheric Resources Research of the Bureau of Reclamation. The field program ran from 18 May through 7 August 1981, involving networks of eight radars—seven Dappler, two dual-wavelength—123 mesonet stations, seven upper-air sounding sites, and 14 research aircraft (of which as many as eight were flown in coordinated missions on single storms). The field program was an operational success, with a lot of convective activity within the densely instrumented area, permitting many relatively complete data sets to be obtained. The data are now becoming available, and the analysis effort is commencing.
EIGHT MYTHS ABOUT CAUSALITY AND STRUCTURAL EQUATION MODELS

Causality was at the center of the early history of structural equation models (SEMs) which continue to serve as the most popular approach to causal analysis in the social sciences. Through decades of development, critics and defenses of the capability of SEMs to support causal inference have accumulated. A variety of misunderstandings and myths about the nature of SEMs and their role in causal analysis have emerged, and their repetition has led some to believe they are true. Our chapter is organized by presenting eight myths about causality and SEMs in the hope that this will lead to a more accurate understanding. More specifically, the eight myths are the following: (1) SEMs aim to establish causal relations from associations alone, (2) SEMs and regression are essentially equivalent, (3) no causation without manipulation, (4) SEMs are not equipped to handle nonlinear causal relationships, (5) a potential outcome framework is more principled than SEMs, (6) SEMs are not applicable to experiments with randomized treatments, (7) mediation analysis in SEMs is inherently noncausal, and (8) SEMs do not test any major part of the theory against the data. We present the facts that dispel these myths, describe what SEMs can and cannot do, and briefly present our critique of current practice using SEMs. We conclude that the current capabilities of SEMs to formalize and implement causal inference tasks are indispensible; its potential to do more is even greater.
Evidence for an oscillator other than luteinizing hormone controlling the secretion of progesterone in cattle.

The objective of this study was to quantify and compare the frequencies of pulses in ovarian and systemic concentrations of progesterone, systemic concentrations of luteinizing hormone (LH) and rate of ovarian blood flow. Blood was collected simultaneously from previously implanted catheters in the ovarian venous circulation and jugular vein on Day 12 or 13 of estrous cycles from 4 nonlactating dairy cows. Blood was collected at a rate of 2.5 mI/mm for 5 mm out of every 10 mm over an 8-h period. The mean rate of blood flow in the ovarian arteryduring the 5-mm collection period was estimated by an electromagnetic blood flow transducer. Pulses were observed over time in both ovarian and systemic concentrations of progesterone at frequencies that ranged between 0.625 and 0.875 cycles/h (1.1to 1.5 h/cycle) among the animals. Only one or two episodes of release of LH were observed during the 8-h period, and transient increasesin blood flow to the ovaries were associatedtemporally with each episode of LH release. The estimated frequencies for release of LH and increased blood flow were the same for each animal and ranged between 0.250 and 0.375 cycles/h. A second cycle with a frequency similar to that for LH was evident in the spectral density functions for ovarian and systemic concentrations of progesterone.This cycle was eliminated when the cycle for LH was removed from the data for progesterone, but the magnitude and frequency of the pulses in progesterone were not affected. These findings suggested that an oscillator other than LH may be partially responsible for regulation of the secretion of progesterone.
Fiscal hedging with nominal assets

Abstract We analyze optimal fiscal and monetary policy in an economy with distortionary labor income taxes, nominal rigidities, nominal debt of various maturities and short-selling constraints. Optimal policy prescribes the almost exclusive use of long term debt. Such debt mitigates the distortions associated with hedging fiscal shocks by allowing the government to allocate them efficiently across states and periods.
Learning Proper and Common Names in Inferential versus Ostensive Contexts

A single, indirect exposure to a novel word provides information that could be used to make a fast mapping between the word and its referent, but it is not known how well this initial mapping specifies the function of the new word. The four studies reported here compare preschoolers' (N = 64) fast mapping of new proper and common names following an indirect exposure requiring inference with their learning of new names following ostension. In Study 1, 3-year-olds were shown an animate-inanimate pair of objects and asked to select, for example, Dax, a dax, or one. Children spontaneously selected an animate over an inanimate object as the referent for a novel proper name, but had no animacy preference in common name or baseline conditions. Next, the children were asked to perform actions on, for example, Dax or a dax, when presented with an array of three objects: the one they had just selected, another member of like kind, and a distracter. An indirectly learned proper name was treated as a marker for the originally selected object only, whereas a new common name was generalized to include the other category member. Study 2 showed that mappings made by inference were as robust as those made by ostension. Studies 3 and 4 demonstrated that even 2-year-olds can learn as much about the function of a new word from an indirect exposure as from ostension.