cssi/SciSciGPT-SciSciNet huggingface dataset:
Applications Of Excimer Lasers For Atmospheric Species Measurements

Excimer lasers are proven sources of high pulse energy and high average power coherent radiation at several wavelength regions throughout the ultraviolet spectrum. If designed properly, excimer lasers can be operated with both low divergence and narrow spectral bandwidth, and using an oscillator - injection-locked amplifier configuration they can be tuned over a 10 to 20 A bandwidth without appreciable loss in energy. Additional wavelength coverage from excimer lasers can be obtained by stimulated Raman scattering. With the development of magnetic switching for the high voltage, high power switches, the electric discharge excimer laser can also be operated reliably for extended periods of time at high pulse rates. All these features make excimer lasers ideal sources of ultraviolet radiation for a variety of remote and in-situ atmospheric species measurements.
Roger boisjoly and the challenger disaster: The ethical dimensions

This case study focuses on Roger Boisjoly's attempt to prevent the launch of the Challenger and subsequent quest to set the record straight despite negative consequences. Boisjoly's experiences before and after the Challenger disaster raise numerous ethical issues that are integral to any explanation of the disaster and applicable to other management situations. Underlying all these issues, however, is the problematic relationship between individual and organizational responsibility. In analyzing this fundamental issue, this paper has two objectives: first, to demonstrate the extent to which the ethical ambiguity that permeates the relationship between individual and organizational responsibility contributed to the Challenger disaster; second, to reclaim the meaning and importance of individual responsibility within the diluting context of large organizations.
Sociodemographic and economic comparisons of children prescribed longer-acting versus short-acting stimulant medications for attention deficit hyperactivity disorder

Little research has been conducted on sociodemographic and cost disparties regarding the use of longer-acting versus short-acting stimulants in the pediatric population. Demographic characteristics and healthcare expenditures of children taking short-acting stimulants versus longer-acting stimulants for attention deficit hyperactivity disorder (ADHD) were compared. Data from the 2000 and 2001 Medical Expenditure Panel Survey, a nationally representative household survey, were analyzed for 221 children exclusively taking short-acting stimulants and 153 children exclusively taking longer-acting stimulants. No disparities in receiving short-acting as opposed to longer-acting stimulants were found by age, gender, race/ethnicity, region of the country, or insurance status. However, children in the latter group were more likely to come from higher income backgrounds and had greater psychotropic medication costs and total healthcare expenditures. For the most part, sociodemographic disparities in medication treatment for ADHD do not appear to exist once a diagnosis has been made.
Radio Source Localization by a Cooperating UAV Team

This paper describes the development of a networked UAV communication, command, and control (NetUAVC3) architecture. The NetUAVC 3 project is divided into three stages. Stage 1 focused on developing algorithms for tying network intelligence and mission-level tasking information into automatic flight controls. Stage 2 will conclude with a demonstration of leashing UAVs to mobile nodes, and Stage 3 will conclude with a demonstration of radio source localization by a cooperating UAV team. This presentation will describe the NetUAVC 3 architecture currently under development. The Stage 1 system will be presented, including the onboard flight management architecture and monitoring and command & control software that exploits the existing AUGNet mesh network. The radio localization problem, in which one or more UAVs react cooperatively to localize the location of a radio emitter, will also be introduced. Source localization is cast as a distributed estimation problem. Aircraft mobility is exploited to improve the observability, in terms of the Fisher Information Matrix, of this estimation problem. Aircraft motion is coordinated through iterative consensus by individual receding horizon controllers on each vehicle.
Regulation of Trypanosoma cruzi infectivity by alpha- and beta-adrenergic agonists: desensitization produced by prolonged treatments or increasing agonist concentrations.

We previously reported that blood forms of Trypanosoma cruzi express alpha- and beta-adrenergic receptors and that binding of specific agonists to these receptors modifies the infective capacity of the parasite in vitro . The present study has revealed that the inhibitory effect of the beta-adrenergic agonist L-isoproterenol and the stimulatory effect of the alpha-adrenergic agonist L-phenylephrine are not produced when the parasite is subjected to prolonged exposure to otherwise effective doses of these agonists or when supraoptimal doses of these agonists are used. We refer to these phenomena as ‘desensitization’ because of their analogy with vertebrate cells becoming desensitized by prolonged exposure to, or relatively high concentrations of, adrenergic agonists. At a constant agonist concentration, T. cruzi desensitization was time-dependent and, when the time of parasite treatment with the agonists was not changed, the higher concentrations of the agonist tested were the most effective in producing desensitization. The reduced infectivity resulting from treatment with optimal doses of L-isoproterenol was accompanied by elevated levels of cyclic adenosine mono- phosphate (cAMP) which were not detectable when L-isoproterenol concentrations producing desensitization were used. This finding implicated cAMP as a likely second signal in the inhibitory mechanisms of this agonist. No significant change in cAMP was detectable in parasites treated with L-phenylephrine, leaving open the question about how optimal doses of this alpha-adrenergic agonist enhance T. cruzi infectivity. Parasite responsiveness to alpha- and beta-adrenergic agonists as well as the desensitization effects define a system which regulates infectivity and could be modified at the host tissue level by naturally occurring agonists.
Analysis of the -Neumann problem along a straight edge

We show there exists an Lp solution, for p ∈ (2,∞), to the Open image in new window-Neumann problem on an edge domain in Open image in new window2 for (0,1)-forms, and we explicitly compute the singularities, which are of complex logarithmic and arctangent type, along the edge, of the solution.
Solution of systems with Toeplitz matrices generated by rational functions

Abstract We consider Toeplitz matrices T n = ( t i − j ) n i , j =0 , where Σ ∞ −∞ t j z j is a formal Laurent series of a rational function R ( z ). A criterion is given for T n to be invertible, in terms of the nonvanishing of a determinant D n involving the zeros of R ( z ), and of order and form independent of n ; i.e., n enters into D n as a parameter, and not so as to complicate D n as n increases. Explicit formulas involving similar determinants are given for the solution of the system T n X = Y in the case where T n is invertible. Formulas are also given for T −1 n in the case where T n −1 and T n are both convertible Suggestions concerning possible computational procedures based on the results are included.
High-temperature (>500 /spl deg C) ultrasonic transducers: an experimental comparison among three candidate piezoelectric materials

High-temperature piezoelectric crystals, including YCa4O(BO3)3, LiNbO3, and AlN, have been studied for use in ultrasonic transducers under continuous operation for 55 h at 550°C. Additionally, thermal ratcheting tests were performed on the transducers by subjecting the crystals to heat treatments followed by ultrasonic performance testing at room temperature and 500°C. The changes resulting from the heat treatments were less than the statistical spread obtained in repeated experiments and were thus considered negligible. Finally, in situ measurements of the pulse-echo response of YCa4O(BO3)3 were performed at temperatures up to 950°C for the first time, showing stable characteristics up to these high temperatures.
Pitting Corrosion of Inconel 600 in High-Temperature Water Containing CuCl2

Abstract Pitting corrosion of Inconel 600 was studied in aqueous sodium and cupric chloride solutions at 60 and 280 C. The pit nucleation potential, Enp, was evaluated in two different concentrations of sodium chloride. Enp decreased with increasing concentrations of the chloride ion and with temperature. On specimen surfaces exposed to cupric chloride solutions, pitting occurred at open circuit potentials nearly equal to or higher than the Enp determined by anodic polarization in 0.01 M NaCl solution. The number and size of the pits increased with increasing concentrations of cupric chloride and dissolved oxygen. On specimens partly covered with polytetrafluorethylene (PTFE) tape (i.e., in the presence of artificial crevices), pitting occurred more easily at low concentrations of CuCl2 (≤ 20 ppm CuCl2 in deaerated solutions at 280 C). Tubes covered with oxide films that formed during the operation of model boilers exhibited greater pitting resistance than tubes with clean surfaces at 280 C, but less resi...
The hypercorrection effect in younger and older adults.

ABSTRACTThe hypercorrection effect, which refers to the finding that errors committed with high confidence are more likely to be corrected than are low confidence errors, has been replicated many times, and with both young adults and children. In the present study, we contrasted older with younger adults. Participants answered general-information questions, made confidence ratings about their answers, were given corrective feedback, and then were retested on questions that they had gotten wrong. While younger adults showed the hypercorrection effect, older adults, despite higher overall accuracy on the general-information questions and excellent basic metacognitive ability, showed a diminished hypercorrection effect. Indeed, the correspondence between their confidence in their errors and the probability of correction was not significantly greater than zero, showing, for the first time, that a particular participant population is selectively impaired on this error correction task. These results potentially...
Combinatorial biosynthesis of lipopeptide antibiotics in Streptomyces roseosporus

Daptomycin is a cyclic lipopeptide antibiotic produced by Streptomyces roseosporus. Cubicin® (daptomycin-for-injection) was approved in 2003 by the FDA to treat skin and skin structure infections caused by Gram-positive pathogens. Daptomycin is particularly significant in that it represents the first new natural product antibacterial structural class approved for clinical use in three decades. The daptomycin gene cluster contains three very large genes (dptA, dptBC, and dptD) that encode the nonribosomal peptide synthetase (NRPS). The related cyclic lipopeptide A54145 has four NRPS genes (lptA, lptB, lptC, and lptD), and calcium dependent antibiotic (CDA) has three (cdaPS1, cdaPS2, and cdaPS3). Mutants of S. roseosporus containing deletions of one or more of the NRPS genes have been trans-complemented with dptA, dptBC, and dptD by inserting these genes under the control of the ermEp* promoter into separate conjugal cloning vectors containing ϕC31 or IS117 attachment (attP int) sites; delivering the plasmids into S. roseosporus by conjugation from Escherichia coli; and inserting the plasmids site-specifically into the chromosome at the corresponding attB sites. This trans-complementation system was used to generate subunit exchanges with lptD and cdaPS3 and the recombinants produced novel hybrid molecules. Module exchanges at positions d-Ala8 and d-Ser11 in the peptide have produced additional novel derivatives of daptomycin. The approaches of subunit exchanges and module exchanges were combined with amino acid modifications of Glu at position 12 and natural variations in lipid side chain starter units to generate a combinatorial library of antibiotics related to daptomycin. Many of the engineered strains produced levels of novel molecules amenable to isolation and antimicrobial testing, and most of the compounds displayed antibacterial activities.
Disk-integrated photometry of Neptune at methane-band and continuum wavelengths

The present disk-integrated photometry of Neptune, which was obtained in 1986 and 1987, is used to study the diurnal and short-term variability; the fact that this photometry was obtained from high-resolution CCD images allows the discrete cloud features' causing of the rotational lightcurve seen at methane-band wavelengths to be definitively demonstrated. A quiescent state of the Neptune atmosphere is suggested by the planet's 8900 A reflectivity in the absence of bright clouds, appears to have remained nearly constant over the observational period.
Relationship of sexual behavior and castration to tumescence in the male rat.

Abstract Previous research has established that the occurrence of erection in the rat is facilitated by spinal transection, and by exogenous androgen treatment after castration. No data have been reported showing the decline in the occurrence of erection in the castrated, spinally intact rat in the absence of exogenous androgen replacement. In this investigation males initially without mating experience were provided from 3–7 mating trials prior to treatment. Castration was carried out on some of the animals and subsequent tests performed on mating and (or) the occurrence of erection. The frequency of erection had not significantly declined in castrated males in comparison to intact males by two months following castration. However, the duration that erection was maintained showed significant decreases by two months following castration. If castrated males were tested until the frequency of behavioral intromissions reached zero, then subsequent tests showed significant reductions in the frequency of erection as well as in the duration that erection was maintained. There was no apparent relationship between intromission frequency and ejaculation observed in the 3–7 mating trials, and erection frequency and penile flips during the later erection trials. It was concluded that the duration that erection is maintained is more sensitive to androgen withdrawal than is the frequency of erection.
The change in structure of surfactant aggregates during adsorption/desorption processes and its effect on the stability of alumina suspension

Abstract The adsorption/desorption behavior of the cationic surfactant tetradecyl trimethyl ammonium chloride (TTAC) at the alumina-water interface and the change in the structure of surfactant aggregates at the interface were studied using the fluorescence spectroscopic technique along with electrophoresis. As expected, the cationic TTAC adsorbed significantly on the negatively charged alumina particles. It was observed that adsorption was reversible in the high concentration range, but in the low concentration range some hysteresis was observed. This can be attributed to the different operative mechanisms for hemimicelle formation and breakup. An energy barrier is proposed for the formation of the TTAC aggregates at the solid-liquid interface with the result that the hemimicelle concentration for the adsorption process is higher than that for the desorption process. This conclusion was further confirmed by the fluorescence spectroscopic test. This adsorption hydsteresis affected dispersion properties of alumina suspension with the maximum settling rate shifting to the lower concentrations.
Electronic communication and sociology: Looking backward, thinking ahead, careening toward the next millennium

L'A. s'interesse aux nouveaux modes de communications. Il estime que ceux-ci vont apporter des changements considerables sur le plan social y compris dans la vie quotidienne. Il affirme que les structures sociales qui ne sont pas concernees par ces changements sont celles qui sont dans une situation de declin sur le plan economique et culturel. Il propose une analyse sociologique des changements sociaux induits par la communication electronique. Il pose le probleme de son controle social. Il souligne que ceux-ci vont bouleverser les modes de communication construits sur un modele sexiste. Il s'efforce d'envisager les evolutions dans le domaine des communications au 21 e siecle
Atmospheric Chemistry in a Changing World

The world is changing,and the atmosphere's composition is changing with it. Human activity is responsible for much of this. Global population growth and migration to urban centers, extensive biomass burning, the spread of fertilizer-intensive agribusiness, globalization of business and industry, rising standards of living in the developing world, and increased energy use fuels atmospheric change. If current practices continue, atmospheric increases are likely for the greenhouse gases carbon dioxide, methane, nitrous oxide; and for the chemically active gases nitric oxide, sulfur dioxide,and ammonia. Increases in global tropospheric ozone and aerosols are a distinct possibility.
A Comparison of Morphologic Features, Flow Cytometry, TCR-Vβ Analysis, and TCR-PCR in Qualitative and Quantitative Assessment of Peripheral Blood Involvement by Sézary Syndrome

The strengths and weaknesses of various laboratory methods for peripheral blood (PB) Sezary cell quantitation have not been compared rigorously. In this study, manual Sezary cell counting, qualitative and quantitative flow cytometry, T-cell receptor (TCR) Vbeta flow cytometry, and TCR polymerase chain reaction were performed on PB specimens from 11 patients with Sezary syndrome (SS), 9 with reactive erythroderma, 6 with mycosis fungoides, and 11 healthy control subjects. These methods identified neoplastic cells in more than 90% of SS cases. The diagnostic specificities of these tests varied; they were enhanced by applying criteria proposed by the International Society for Cutaneous Lymphoma. Comparison of sequentially analyzed specimens from 6 patients with SS revealed that although the absolute number of clonal cells was reduced, in some cases, these cells still constituted the vast majority of the CD4+ T-cell subset, suggesting that quantitative subset analysis might be sufficient to monitor changes in the PB tumor burden.
Analysis of proteinaceous components of the organic matrices of spicules from the gorgonian Leptogorgia virgulata

Abstract 1. 1. Spicules of Leptogorgia virgulata contain a water-soluble organic matrix composing 0.62% of the spicule weight and a water-insoluble fraction comprising 5.29% of the spicule weight. 2. 2. The soluble fraction shows a particularly high aspartate content followed by glycine, alanine and glutamate. Aspartate, glycine, glutamate and alanine are the most abundant residues in the insoluble fraction. 3. 3. SDS-gel electrophoresis of both matrices shows protein fractions at approx. 100,000, 99,000 and 80,000 daltons. The soluble matrix shows five additional faint bands. Both fractions stain for a carbohydrate at 100,000-99,000 daltons indicating a glycoprotein at this molecular weight. 4. 4. The gorgonian matrix displays many similarities to those of other calcifying organisms.
A polarimetric interferometry-based optical fibre pressure sensor with potential application to flow measurement

Abstract The force/pressure induced birefringence in an ordinary single mode optical fibre has been investigated as a possible element for a differential pressure flow sensor. The relative sensitivities of coated and uncoated fibres at various temperatures have been measured using polarimetric interferometry. The sensitivity of an uncoated sensing fibre was found to be increased by 18% over that of the coated fibre. Results are presented showing good linearity and acceptable stability in measurements over the temperature range 20°C to 95°C, and application to flow sensing are discussed.
Monoclonal antibodies to human neuron-specific enolase reveal heterogeneity of the enzyme in neurons of the central nervous system

Three monoclonal antibodies to human neuron-specific enolase (NSE) were used to survey the human brain and spinal cord for immunoreactivity. Two of the antibodies (EB and CF) recognized the same population of cells and cell processes. Reactivity was restricted to myelinated axons, basket cell bodies and processes, and a small population of pyramidal cell bodies in the visual cortex. The third antibody (AD) reacted with some, but not all, of the neuronal cell bodies in cerebral cortex, hippocampus, midbrain, and spinal cord. Many neurons did not react with any of the antibodies. The epitope recognized by AD was trypsin-sensitive, while those recognized by EB and CF were not. These studies suggest that NSE may have multiple conformational or structural forms which are segregated between the cell body and axon.
Antimicrobial de-escalation strategies in hospitalized patients with pneumonia, intra-abdominal infections, and bacteremia†

Increasing numbers of serious hospital/healthcare- or community-acquired infections are caused by resistant (often multi-drug resistant) bacterial pathogens. Because delayed or ineffective initial therapy can have severe negative consequences, patients at risk for these types of infections typically receive initial empiric antibiotic therapy with a broad-spectrum regimen covering the most likely pathogens, based on local surveillance data and risk factors for infection with a resistant microorganism. While improving the likelihood of a successful outcome, use of broad-spectrum, often high-dose, empiric antimicrobial therapy also creates pressure for the selection or development of resistant microorganisms, as well as increasing costs and possibly exposing patients to adverse events or collateral damage such as Clostridium difficile-associated disease. De-escalation is a strategy that attempts to balance the competing aims of providing initial empiric therapy that is appropriate and covers the likely pathogens, and limiting antimicrobial exposure and increased risk for emergence of resistant pathogens. More specifically, the de-escalation strategy involves collection of cultures for later microbiological assessment before initiating broad-spectrum empiric therapy covering the most likely pathogens, with the intention of streamlining or de-escalating to a more narrow-spectrum antimicrobial regimen 2-3 days later if warranted by clinical status and culture results. In some cases, negative culture results and subsequent clinical review may allow for termination of initial empiric therapy. In this manner, de-escalation enables more effective targeting of the causative pathogen(s), elimination of redundant therapy, a decrease in antimicrobial pressure for emergence of resistance, and cost savings. This article examines application of the de-escalation strategy to 3 case patients, one with healthcare-associated pneumonia, another with complicated intra-abdominal infection, and a third with central line-associated bacteremia. Journal of Hospital Medicine 2012;7:S13-S21. © 2012 Society of Hospital Medicine.
Sixth-Order Radiative Corrections to the Electron Magnetic Moment

We have calculated the contribution of fifty Feynman diagrams of the order ${\ensuremath{\alpha}}^{3}$ to the electron magnetic moment. Our result, $(1.02\ifmmode\pm\else\textpm\fi{}0.04){(\frac{\ensuremath{\alpha}}{\ensuremath{\pi}})}^{3}$, agrees with the result of Levine and Wright, and is about 5 times more accurate. Together with the contribution from the rest of the ${\ensuremath{\alpha}}^{3}$ diagrams calculated previously, the complete theoretical prediction for the electron anomaly up to the order ${\ensuremath{\alpha}}^{3}$ is $\frac{\ensuremath{\alpha}}{2\ensuremath{\pi}}\ensuremath{-}0.32848{(\frac{\ensuremath{\alpha}}{\ensuremath{\pi}})}^{2}+(1.29\ifmmode\pm\else\textpm\fi{}0.06){(\frac{\ensuremath{\alpha}}{\ensuremath{\pi}})}^{3}$, in good agreement with the latest experimental result.
Mercury in tissues of mussel off southern California

Abstract Total mercury content has been determined in three tissues of the intertidal mussel Mytilus californianus collected at locations along the southern California coast and at island control stations. The apparent influence of certain harbours and municipal wastewater outfalls was reflected by the relatively higher levels of mercury in all tissues of mussels from these areas. In general, the concentrations reported here are lower than those in mussels on west European coasts.
Heat transfer to wavy wall in hypersonic flow.

Two-dimensional multiple wave distortions effect on heat transfer to wall in hypersonic flow
Interaction of antioxidants with ozone and herbicide stress

Antioxidants are compounds used to prevent the reactions of organic materials with molecular oxygen. Antioxidants are used to protect foods and other products from discoloration and spoilage, thus sodium benzoate is added to bread to prolong its shelf life. Other antioxidants such as piperonyl butoxide (..cap alpha..-(2-(2-butoxyethoxy)ethoxy)-4,5-methylenedioxy-2-propyltoluene) and sesamex (a component of sesame oil) are used as insecticide synergists. Both of these compounds are potent microsomal mixed function oxidase (m.f.o.) inhibitors and when applied in combination with certain insecticides increase the insecticide's potency by decreasing the rate at which insects can detoxify the insecticides. In plants, EDU (N-(2-(2-oxo-1-imidazolidiny)ethyl)-N-phenylurea has been reported to protect pinto beans (Phaseolus vulgaris L.) and piperonyl butoxide to protect tobacco (Nicotiana tabacum L.) from ozone injury. The purpose of this study was to a) evaluate the antioxidants EDU, piperonyl butoxide, and n-propyl gallate, as protectants against ozone injury in navy bean, and b) to determine if these antioxidants could function as herbicide synergists just as piperonyl butoxide functions as an insecticide synergist.
Elemental analysis of a single-wall carbon nanotube candidate reference material

A material containing single-wall carbon nanotubes (SWCNTs) with other carbon species, catalyst residues, and trace element contaminants has been prepared by the National Institute of Standards and Technology for characterization and distribution as Standard Reference Material SRM 2483 Carbon Nanotube Soot. Neutron activation analysis (NAA) and inductively coupled plasma mass spectrometry (ICP–MS) were selected to characterize the elemental composition. Catalyst residues at percentage mass fraction level were determined with independent NAA procedures and a number of trace elements, including selected rare earth elements, were determined with NAA and ICP–MS procedures. The results of the investigated materials agreed well among the NAA and ICP–MS procedures and good agreement of measured values with certified values was found in selected SRMs included in the analyses. Based on this work mass fraction values for catalyst and trace elements were assigned to the candidate SRM.
Comparing Vignette Instruction and Assessment Tasks to Classroom Observations and Reflections

The growing body of research on the use of vignettes in teacher education courses suggests that vignette-based instruction and assessment tasks may represent a viable alternative to traditional forms of scaffolded instruction and reflective essays following classroom observations, thereby creating a bridge between college and K–12 classrooms for teacher candidates. In this study, the authors compare the effectiveness of vignette instruction and assessment tasks with teacher observation-reflections on subject matter mastery in two sections of an online graduate educational psychology course. One section completed vignette assessment tasks while a second section wrote reflective essays following K–12 classroom observations. Both sections also completed a cumulative posttest (ten forced-choice items, a vignette task, and a video reflection task). Results confirmed the null hypothesis that there would be no significant differences in mastery of subject matter across the two groups, extending the effective app...
Adenosine therapy for supraventricular tachycardia during pregnancy.

Abstract Our results suggest that the use of intravenous adenosine for termination of maternal SVT during the second and third trimester of pregnancy is safe and effective. The development of fetal bradycardia following administration of multiple antiarrhythmic drugs emphasizes the importance of fetal heart rate monitoring during acute antiarrhythmic therapy. Further study is necessary to determine the safety of adenosine use during the first trimester of pregnancy.
Psychometric assessment of the Temptations to Try Alcohol Scale.

Abstract Effective interventions require an understanding of the behaviors and cognitions that facilitate positive change as well as the development of psychometrically sound measures. This paper reports on the psychometric properties of the Temptations to Try Alcohol Scale (TTAS), including factorial invariance across different subgroups. Data were collected from 3565 6th grade RI middle school students. Structural equation modeling was used to determine the appropriate factorial invariance model for the 9-item TTAS. The measure consists of three correlated subscales: Social Pressure, Social Anxiety, and Opportunity. Three levels of invariance, ranging from the least to the most restrictive, were examined: Configural Invariance, which constrains only the factor structure and zero loadings; Pattern Identity Invariance, which requires factor loadings to be equal across the groups; and Strong Factorial Invariance, which requires factor loadings and error variances to be constrained. Separate analyses evaluated the invariance across two levels of gender (males vs. females), race (white vs. black) ethnicity (Hispanic vs. Non-Hispanic) and school size (small, meaning
MEASUREMENT OF OXYGEN CONSUMPTION OF THE PELVIC LIMB IN FETAL SHEEP

Accurate measurement of substrate uptake by fetal hindlimb tissues has been limited due to difficulties with simultaneous substrate sampling and blood flow measurement. We describe continuous ultrasonic blood flow measurement in 5 fetal sheep (8-14 days post-op) catheterized for sampling unobstructed blood flow to and from a pelvic limb. Each flow transducer (Transonics Systems, Inc) was calibrated in vitro, in vivo (zero flow) and compared with microsphere measurement. Six sample sets for O2 content were drawn from the external iliac artery ([O2]a, mM) and vein ([O2”v, mM) while blood flow through the external iliac artery (F, ml/min) was measured continuously under control conditions and after pancuronium. O2 uptake (VO2, μm/min) was calculated; results are expressed as mean ± sem for the five fetuses and mean coefficient of variation within sample sets: The study limb blood flow ratio (ultrasonic/microsphere) = 1.033. The microsphere blood flow ratio (study limb/non-study limb) = 1.028. We conclude that 1) the described method for continuous blood flow measurement is accurate, and 2) the spontaneous variability of [O2], F, and VO2 can be decreased by neuromuscular blockade. Tissues with spontaneous changes in metabolic activity, such as the pelvic limb, require Doth continuous blood flow recording and multiple determinations of substrate arteriovenous differences to best describe their metabolism.
Discovery of a small molecule Tat-trans-activation-responsive RNA antagonist that potently inhibits human immunodeficiency virus-1 replication.

Abstract Antiretroviral therapy to treat AIDS uses molecules that target the reverse transcriptase and protease enzymes of human immunodeficiency virus, type 1 (HIV-1). A major problem associated with these treatments, however, is the emergence of drug-resistant strains. Thus, there is a compelling need to find drugs against other viral targets. One such target is the interaction between Tat, an HIV-1 regulatory protein essential for viral replication, and trans-activation-responsive (TAR) RNA. Here we describe the design and synthesis of an encoded combinatorial library containing 39,304 unnatural small molecules. Using a rapid high through-put screening technology, we identified 59 compounds. Structure-activity relationship studies led to the synthesis of 19 compounds that bind TAR RNA with high affinities. In the presence of a representative Tat-TAR inhibitor (5 μm TR87), we observed potent and sustained suppression of HIV replication in cultured cells over 24 days. The same concentration of this inhibitor did not exhibit any toxicity in cell cultures or in mice. TR87 was also shown to specifically disrupt Tat-TAR binding in vitro and inhibit Tat-mediated transcriptional activation in vitro and in vivo, providing a strong correlation between its activities and inhibition of HIV-1 replication. These results provide a structural scaffold for further development of new drugs, alone or in combination with other drugs, for treatment of HIV-1-infected individuals. Our results also suggest a general strategy for discovering pharmacophores targeting RNA structures that are essential in progression of other infectious, inflammatory, and genetic diseases.
Preferential Course Scheduling

An academic department of a college or university typically constructs its yearly schedule of classes in two stages. First, each faculty member is assigned a set of classes or course sections to teach during the year. Following that days, times, and room numbers are assigned to each course section. These two procedures are almost universally performed manually, demanding various degrees of combinatorial skill and political astuteness on the part of the course scheduler. Depending on the size of the department and the diversity of course offerings, the time required to construct such a schedule of classes can range from a perfunctory afternoon's work to an intensive month-long ordeal. Recent work by Dyer and Mulvey [Dyer, James, John Mulvey. 1976. An integrated optimization/information systems for academic departmental planning. Management Science22 12, August 1332--1341; Dyer, James, John Mulvey. 1977. Computerized scheduling and planning. New Directions for Institutional Research13 Spring 67--86.] has addressed the problem of assigning faculty members to specific classes or course sections. They developed a network flow model that was successfully used to assign faculty members to course sections at the Graduate School of Management at UCLA.
Optimal experimental design for systems with bivariate failures under a bivariate Weibull function

Summary In manufacturing industry, it may be important to study the relationship between machine component failures under stress. Examples include the failures of integrated circuits and memory chips in electronic merchandise given various levels of electronic shock. Such studies are important for the development of new products and for the improvement of existing products. We assume two-component systems for simplicity and we assume that the joint probability of failures increases with stress as a cumulative bivariate Weibull function. Optimal designs have been developed for two correlated binary responses by using the Gumbel model, the bivariate binary Cox model and the bivariate probit model. In all these models, the amount of damage ranges from −∞ to ∞. In the Weibull model, the amount of damage is positive, which is natural for experimental factors such as voltage, tension or pressure. We describe locally optimal designs under bivariate Weibull assumptions. Since locally optimal designs with non-linear models depend on predetermined parameter values, misspecified parameter values may lead to inefficient designs. However, we find that optimal designs under the Weibull model are surprisingly efficient over a wide range of misspecified parameter values. To improve the efficiency, we recommend a multistage procedure. We show how using a two-stage procedure can provide a substantial improvement over a design that was optimal for misspecified parameters.
Simple urodynamic evaluation ofincontinent elderly female nursing home patients A descriptive analysis

Abstract We present a descriptive analysis of the functional, mental, and urodynamic status of a population of incontinent elderly female nursing home patients. One hundred fifty-five intermediate care female patients with a mean age of 85.5 years were identified as being incontinent of urine at least once daily. After urologic evaluation, each patient was classified into one of four categories: incontinence with normal cystometrogram 68 (44 &), detrusor instability (DI) 52 (34 &) stress incontinence (SI) 27 (17 &), or overflow incontinence (01) 7 (4 &). Thirteen weeks later, patients were again studied using simple water cystometry. At follow-up evaluation, 45 patients (33 &) had urodynamic findings which differed from the initial evaluation. Of these women, 10 with DI, 12 with SI, and 2 with OI were found to have normal cystometric parameters at the time of follow-up study, while 19 (14 &) who initially had normal cystometric findings had evidence of DI (11) or SI (3). Strong correlation between urinary incontinence in patients with normal cystometric findings and moderate to severe cognitive impairment was present. Simple urodynamic evaluation did identify patients with SI and 01 who might benefit from specific therapy. Urodynamic evaluation of incontinent elderly female nursing home patients is indicated and may provide direction for planning treatment strategies.
Monoamine‐containing neurons in the central nervous system and peripheral nerves of the leech, Hirudo medicinalis

The 34 ganglia of the leech (Hirudo medicinalis) central nervous system together with their connectives and roots have been studied by means of the fluorescence histochemical technique for monoamines. More than half the ganglia of the central nervous system possess the same number of monoamine-containing neurons in a fixed location. These identical ganglia consist of seven yellow fluorescent monoamine-containing neuron perikarya located within the ganglia and a pair of blue-green fluorescent monoamine-containing perikarya located outside the ganglia in the anterior roots. A neuropile consisting of a dense network of yellow and blue-green fluorescent varicose processes, several smooth blue-green fluorescent processes and occasional smooth yellow fluorescent processes is present in the ganglia. Smooth and varicose yellow and blue-green fluorescent processes are found in the connectives and roots of the ganglia. The intraneuronal distribution of fluorescence within the nine monoamine-containing neurons of identical ganglia is described. The monoamine-containing neurons of the remaining ganglia of the central nervous system are described. These ganglia are shown to vary only slightly from the pattern of identical ganglia.
The Role of Aid and Capital Flows in Economic Development

when Mexico defaulted on its debt repayments, annual capital flows to developing countries amounted to $100 billion and official concessional aid flows consisted of an additional $50 billion. After the debt crisis, commercial flows dried up almost completely with net transfers of capital from borrowing countries to their lenders. The concessional flows which had grown dramatically in the 1970s also stagnated in real terms. Over the four post-World War II decades, billions of dollars have been transferred from developed to developing countries. During this period there have been major structural changes in the patterns of external assistance including the graduation of a number of recipients, such as Greece, Taiwan, and South Korea, the decline of the U.S. role as a donor, the rise of Europe and Japan in external assistance, and a shift of aid resources from Asia to Africa. Whether these transfers have succeeded in stim-
Androgen therapy in haemodialysis patients. II. Effects on red cell metabolism.

Summary. Activities of the red cell enzymes hexokinase, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, lactic dehydrogenase and aspartate amino-transferase were measured in 17 chronic haemodialysis patients receiving androgen therapy, 15 untreated chronic haemodialysis patients and 15 normal subjects. Compared to normal subjects, untreated haemodialysis patients had similar reticulocyte counts but significantly increased levels of all five enzymes studied. This finding suggests the presence of a younger red cell population in the peripheral blood and is consistent with the shortened red cell survival known to occur in this clinical setting. Red cell enzyme activities in untreated haemodialysis patients were significantly corre-lated with one another and with the serum phosphate level. Moreover, in this population, red cell DPG content was directly related to hexokinase and glucose 6-phosphate dehydrogenase activities while haemoglobin-oxygen affinity (P50) was inversely related to all five enzyme activities. In contrast, in androgen-treated haemodialysis patients, despite higher reticulocyte counts, red cell enzyme activities were the same or lower than those in the untreated haemodialysis group and only slightly higher than those in normal subjects, suggesting an overall older red cell population. Moreover, relationships of red cell enzymes to one another, to serum phosphate- levels and to both red cell DPG content and haemoglobin-oxygen affinity were significantly different in androgen-treated subjects than in the untreated haemodialysis group. These changes are consistent with a direct effect of androgens on red cell metabolism and an improved red cell survival during androgen therapy.
Resolving ancient radiations: can complete plastid gene sets elucidate deep relationships among the tropical gingers (Zingiberales)?

Background and Aims Zingiberales comprise a clade of eight tropical monocot families including approx. 2500 species and are hypothesized to have undergone an ancient, rapid radiation during the Cretaceous. Zingiberales display substantial variation in floral morphology, and several members are ecologically and economically important. Deep phylogenetic relationships among primary lineages of Zingiberales have proved difficult to resolve in previous studies, representing a key region of uncertainty in the monocot tree of life. Methods Next-generation sequencing was used to construct complete plastid gene sets for nine taxa of Zingiberales, which were added to five previously sequenced sets in an attempt to resolve deep relationships among families in the order. Variation in taxon sampling, process partition inclusion and partition model parameters were examined to assess their effects on topology and support. Key Results Codon-based likelihood analysis identified a strongly supported clade of ((Cannaceae, Marantaceae), (Costaceae, Zingiberaceae)), sister to (Musaceae, (Lowiaceae, Strelitziaceae)), collectively sister to Heliconiaceae. However, the deepest divergences in this phylogenetic analysis comprised short branches with weak support. Additionally, manipulation of matrices resulted in differing deep topologies in an unpredictable fashion. Alternative topology testing allowed statistical rejection of some of the topologies. Saturation fails to explain observed topological uncertainty and low support at the base of Zingiberales. Evidence for conflict among the plastid data was based on a support metric that accounts for conflicting resampled topologies. Conclusions Many relationships were resolved with robust support, but the paucity of character information supporting the deepest nodes and the existence of conflict suggest that plastid coding regions are insufficient to resolve and support the earliest divergences among families of Zingiberales. Whole plastomes will continue to be highly useful in plant phylogenetics, but the current study adds to a growing body of literature suggesting that they may not provide enough character information for resolving ancient, rapid radiations.
On the definition of surface potentials for finite-difference operators

For a class of linear constant-coefficient finite-difference operators of the second order, we introduce the concepts similar to those of conventional single- and double-layer potentials for differential operators. The discrete potentials are defined completely independently of any notion related to the approximation of the continuous potentials on the grid. We rather use an approach based on differentiating, and then inverting the differentiation of, a function with surface discontinuity of a particular kind, which is the most general way of introducing surface potentials in the theory of distributions. The resulting finite-difference “surface” potentials appear to be solutions of the corresponding system of linear algebraic equations driven by special source terms. The properties of the discrete potentials in many respects resemble those of the corresponding continuous potentials. Primarily, this pertains to the possibility of representing a given solution to the homogeneous equation on the domain as a variety of surface potentials with the density defined on the domain's boundary. At the same time, the discrete surface potentials can be interpreted as one specific realization of the generalized potentials of Calderon's type, and consequently, their approximation properties can be studied independently in the framework of the difference potentials method by Ryaben'kii. The motivation for introducing and analyzing the discrete surface potentials was provided by the problems of active shielding and control of sound, in which the aforementioned source terms that drive the potentials are interpreted as the acoustic control sources that cancel out the unwanted noise on a predetermined region of interest.
Erosion profiles due to particles entrained by wind: Application of an eolian sediment-transport model

Erosion by impacts of particles entrained in the wind scales with the kinetic energy of impacting grains. A recent model of eolian sediment transport permits calculation of expected erosion patterns in objects of simple geometry. The modeling of vertical erosion profiles, in turn, provides an exacting test of the transport model. Realistic distributions of liftoff velocities for saltating grains give rise to kinetic-energy–flux profiles characterized by a strong maximum as much as .1–.4 m above the bed during strong winds. Kinetic-energy flux due to suspended grains also peaks above the bed; the height and strength of the maxima depend very strongly on the grain-size distribution. As grain size diminishes, increased particle deflection by the air flow around an obstacle reduces delivery of kinetic energy to the surface. For both saltating and suspended grains, kinetic-energy flux scales with the fifth power of the wind shear velocity. Erosion profiles in man-made obstacles are well modeled with only slight modification of the saltation model to account for the relatively high elasticity of actual deflationary surfaces, lending considerable support for the model. The modeling also elucidates several aspects of ventifaction. As small ventifacts (.1–.2 m in diameter) and the lower portions of larger ones are predominantly eroded by saltating grains, upwind surface irregularities are quickly damped, leading to facets that dip upwind and sharply truncate lee surfaces. Sandblasting by suspended grains dominates along the upper portions of large ventifacts, where grain paths are partially deflected by the obstacle, and may lead to radially symmetrical flutes and grooves.