cssi/SciSciGPT-SciSciNet huggingface dataset:
Modifying effect of colicin on experimental Shigella keratoconjunctivitis.

Abstract The ability of colicinogenic bacteria and colicin to inhibit Shigella sonnei during the course of infection was studied. Infection of the guinea pig conjunctivae was used as the experimental model. In S. sonnei-infected guinea pig conjunctivae which were treated with a colicinogenic strain of Escherichia coli or with colicin, the number of S. sonnei cells was lower than in animals infected with S. sonnei but not treated. The decrease in the number of pathogenic organisms was associated with absence of disease. A noncolicinogenic strain of E. coli had no effect on production of disease in infected animals. Treatment with a colicinogenic strain of E. coli or colicin did not affect the production of disease or the numbers of organisms in an animal infected with a colicin-resistant strain of S. sonnei.
Early years in artificial valve development.

Abstract Various types prosthetic heart valves developed and tested in the laboratory beginning in 1958 are described. Seven of such valves were implanted clinically in patients with congestive heart failure previously operated on by both the closed and open techniques in 1958 and 1959. The longest survivor was 6 weeks. Evidence is presented demonstrating that putting a film of polyurethane on the Teflon leaflet valve and fixation rings of disc valves reduces thrombosis, thromboembolism, and tissue overgrowth interfering with disc or ball valve function.
Effects of chronic administration of ethanol on gastric secretion of acid in dogs.

The effects of an excessive intake of ethanol on gastric acid secretion was investigated up to 14 months in 6 dogs. After the daily administration of 4.4 g/kg of ethanol as a 40% solution through the esophagostomy was initiated, mean daily secretion of acid from a Heidenhain pouch increased from 5.22 to 12.55 mEq during the first month and remained elevated throughout the entire period of observation. The mean maximal acid output (MAO) increased also from 19.54 to 26.3 mEq within 1 month after the daily administration of ethanol began. The increased MAO, however, tended to decrease with the passage of time and at the end of 6 months, it was no different, statistically, from that of the pre-ethanol level. Factors possibly responsible for the increase in acid secretion are discussed.
Using real-time queueing theory to control lateness in real-time systems

This paper presents real-time queueing theory, a new theory which embeds the ability of real-time scheduling theory to determine whether task timing requirements are met into the context of queueing models. Specifically, this paper extends the analysis developed in Lehoczky [9] to the GI/M/1 case. The paper also applies these models to study queue control strategies which can control customer lateness. Arriving customers have deadlines drawn from a general deadline distribution. The state variable for the queueing system must include the number in the queue (with supplementary variables as needed to create a Markov model) and the lead-time (deadline minus current time) of each customer; thus the state space is infinite dimensional. One can represent the state of the system as a measure on the real line and can represent that measure by its Fourier transform. Thus, a real-time queueing system can be characterized as a Markov process evolving on the space of Fourier transforms, and this paper presents a characterization of the instantaneous simultaneous lead-time profile of all the customers in the queue. This profile is complicated; however, in the heavy traffic case, a simple description of the lead-time profile emerges, namely that the lead-time profile behaves like a Brownian motion evolving on a particular manifold of Fourier transforms; the manifold depending upon the queue discipline and the customer deadline distributions. This approximation is very accurate when compared with simulations. Real-time queueing theory focuses on how well a particular queue discipline meets customer timing requirements, and focuses on the dynamic rather than the equilibrium behavior of the system. As such, it offers the potential to study control strategies to ensure that customers meet their deadlines. This paper illustrates the analysis and performance evaluation for certain queue control strategies. Generalizations to more complicated models and to queueing networks are discussed.
Avoidance behavior of juvenile striped bass, Morone saxatilis , subjected to simultaneous chlorine and elevated temperature conditions

The avoidance responses of juvenile striped bass (Morone saxatilis) were evaluated by exposing test organisms to simultaneous elevated temperature (0, 2, 4, and 6‡C) and total residual chlorine (TRC) (0.00, 0.05, 0.10 and 0.15 mg/L) conditions at four acclimation temperatures ranging from 15–30‡C. An unbalanced 3-factor factorial design was used to develop response surface avoidance models at all acclimation temperatures. The percent avoidance models at 15‡C showed that the interaction term (TRC×δT) was the most important term influencing avoidance; TRC was the most important factor at 20‡C; the models at 25 and 30‡C showed that δT was the most important factor. The results of tests conducted at 15‡C suggest that preference for a higher temperature overrides a chlorine avoidance response to 0.15 mg/L TRC. Avoidance responses of striped bass tested at acclimation temperatures of 20, 25, and 30‡C showed that preference for a higher temperature (6‡C δT) did not override a chlorine avoidance response. A significant difference (p<0.01) existed between avoidance models at all acclimation temperatures; greatest avoidance generally occurred for all combinations of test conditions at 30‡C.
Different personal propensities among scientists relate to deeper vs. broader knowledge contributions.

Scientific journal publications, and their contributions to knowledge, can be described by their depth (specialized, domain-specific knowledge extensions) and breadth (topical scope, including spanning multiple knowledge domains). Toward generating hypotheses about how scientists’ personal dispositions would uniquely predict deeper vs. broader contributions to the literature, we assumed that conducting broader studies is generally viewed as less attractive (e.g., riskier) than conducting deeper studies. Study 1 then supported our assumptions: the scientists surveyed considered a hypothetical broader study, compared with an otherwise-comparable deeper study, to be riskier, a less-significant opportunity, and of lower potential importance; they further reported being less likely to pursue it and, in a forced choice, most chose to work on the deeper study. In Study 2, questionnaire measures of medical researchers’ personal dispositions and 10 y of PubMed data indicating their publications’ topical coverage revealed how dispositions differentially predict depth vs. breadth. Competitiveness predicted depth positively, whereas conscientiousness predicted breadth negatively. Performance goal orientation predicted depth but not breadth, and learning goal orientation contrastingly predicted breadth but not depth. Openness to experience positively predicted both depth and breadth. Exploratory work behavior (the converse of applying and exploiting one’s current knowledge) predicted breadth positively and depth negatively. Thus, this research distinguishes depth and breadth of published knowledge contributions, and provides new insights into how scientists’ personal dispositions influence research processes and products.
Microscopic form factor calculations for the quasielastic (6Li, 6He) reactions☆

Abstract We present a simple procedure for calculating microscopic form factors for quasielastic reactions which does not make us of a multipole expansion of the interaction potential. The form factor of the ( 6 Li, 6 He) reactions is studied to reveal its general properties.
Fe Al 2 O 4 -Mg Al 2 O 4 : Growth and Some Thermal, Optical, and Magnetic Properties of Mixed Single Crystals

Synthetic single crystals of Fe${\mathrm{Al}}_{2}$${\mathrm{O}}_{4}$ have been grown from the melt. Measurements of the thermal conductivity $K$ and optical absorption coefficient $\ensuremath{\alpha}$ have been made on a combination of synthetic and natural single crystals of ${\mathrm{Mg}}_{1\ensuremath{-}x}{\mathrm{Fe}}_{x}{\mathrm{Al}}_{2}{\mathrm{O}}_{4}$ for $0\ensuremath{\le}x\ensuremath{\le}1$. The $\ensuremath{\alpha}$ measurements at 300\ifmmode^\circ\else\textdegree\fi{}K in the absorption band of tetrahedral ${\mathrm{Fe}}^{2+}$ between 0.4 and 0.6 eV have been calibrated and then used to measure $x$. The thermal conductivity results between 3 and 300\ifmmode^\circ\else\textdegree\fi{}K show that the heat is conducted by phonons and that tetrahedral ${\mathrm{Fe}}^{2+}$ is a very effective phonon scatterer at all temperatures because it possesses a series of low-lying energy levels in the $3d$ shell. This type of scattering is absent in Co${\mathrm{Al}}_{2}$${\mathrm{O}}_{4}$. The phonon scattering by ${\mathrm{Fe}}^{2+}$ is dominant for $xg0.1$, and for these crystals $\mathrm{K}\ensuremath{\sim}\frac{T}{\ensuremath{\surd}x}$. The magnetic susceptibility $\ensuremath{\chi}$ of a single crystal of Fe${\mathrm{Al}}_{2}$${\mathrm{O}}_{4}$, measured between 2 and 290\ifmmode^\circ\else\textdegree\fi{}K, shows a peak at 9.5\ifmmode\pm\else\textpm\fi{}0.5\ifmmode^\circ\else\textdegree\fi{}K. The analysis of the $\ensuremath{\chi}$ and $K$ measurements suggests that the \ensuremath{\sim}10\ifmmode^\circ\else\textdegree\fi{}K transition is caused by the individual ${\mathrm{Fe}}^{2+}$ ions, and is not associated with a longrange, antiferromagnetic ordering of the Fe${\mathrm{Al}}_{2}$${\mathrm{O}}_{4}$.
Behavioural time budgets of broiler chickens reared in varying light intensities

Abstract Light management is a critical component of production for intensively housed animals. To increase productivity, broiler chickens are often raised commercially in houses that are dimly illuminated on a near-continuous basis. There have been relatively few studies examining the effects of light intensity on the behaviour of broilers. We evaluated the time budgets of broilers (N = 464) housed under one of three photophase light levels (5, 50 or 200 lx) chosen to produce low, moderate or high illumination contrasts with the scotophase light level (1 lx). There were four replicate pens of broilers per treatment. We recorded behaviour for 48 continuous hours during weeks 3, 4, and 5 of age and analysed the time broilers spent exhibiting eight behaviours and two behavioural categories (inactive and active) during the overall photoperiod, photophase and scotophase. There were only two main effects of light intensity on behaviour during the overall photoperiod: 5 lx broilers preened and foraged less than the 50 (P = 0.03, P = 0.03, respectively) and 200 lx birds (P
Beyond checklists: Using clinician prompts to achieve meaningful ICU quality improvement

Background Checklists may reduce errors of omission for critically ill patients. Methods Objective To determine whether prompting to use a checklist improves process of care and clinical outcomes. Design Prospective, concurrently-controlled cohort study with additional historical controls. Setting Medical intensive Care Unit (MICU) of a tertiary care university hospital. Subjects All patients admitted to either of two independent MICU teams. Intervention Intervention team physicians were prompted to address six parameters from a daily rounding checklist if overlooked during morning work rounds. The second team (control) used the identical checklist without prompting. Pre-intervention patients received neither a checklist nor prompting. Outcomes Primary outcome included differences between the prompted and control groups related to several key quality indicators being investigated- ventilator-free days, duration of empirical antibiotics, duration of central venous catheters, duration of foley urinary catheter, pharmacological deep vein thrombosis (DVT) prophylaxis per eligible days and, stress ulcer prophylaxis per eligible days. Secondary outcome included ICU mortality, hospital mortality, ICU length of stay and ventilator associated pneumonia. Results One hundred and forty prompted group patients were compared with 125 concurrent control patients and 1283 pre-intervention patients. Compared with control patients, patients admitted to the service with prompting experienced increased ventilator-free days, decreased empirical antibiotic and central venous catheter duration, and increased rates of deep vein thrombosis and stress ulcer prophylaxis. Prompted group patients had lower risk-adjusted ICU mortality compared with the control group (odds ratio, 0.36; 95% confidence interval, 0.13-0.96; P = 0.041) and lower hospital mortality compared with the control group (10.0 vs. 20.8%; P = 0.014), which remained significant after risk adjustment (adjusted odds ratio, 0.34; 95% confidence interval, 0.15-0.76; P = 0.008). Observed-to-predicted ICU length of stay was lower in the prompted group compared with control (0.59 vs. 0.87; P = 0.02). Checklist availability alone was not associated with reductions in mortality or length of staycompared with the pre-intervention patients. Conclusions In this single-site, preliminary study, checklist-based prompting improved multiple processes of care, and may have improved mortality and length of stay, compared with a stand-alone checklist. The manner in which checklists are implemented is of substantial importance in the care of critically ill patients.
DC technology for stable and reliable grids

The expansion of cities often leads to enlarged load concentration and carries extra challenges to managing the electrical grid while insuring power availability to critical loads. The developing Shanghai power grid faces many challenges in the areas of generation, transmission, and distribution of the rapidly growing amounts of electrical energy in demand. Its development should address issues of congestion, voltage-stability, power restriction, permits, and scarcity of land or right of way. In this paper, an equivalent model of Shanghai power grid is implemented using the ABB power transient software analyzer (SIMPOW) where detailed modeling of the generators including exciters and governors is performed. Solutions including Fault Current Limiters (FCL), Static Var Compensators Light (SVC-Light®) and High Voltage Direct Current (HVDC) systems were analyzed to assess their effectiveness in addressing the grid issues stated above. The best solution was obtained when the individual AC subsystems were decoupled so a fault in a given subsystem is not propagated to another subsystem and short-circuit currents are limited only by local generation capacity. This solution was obtained using a DC ring where power sources and loads are connected to a common DC bus through Voltage Source Converters (VSC).
Phylogenetic Analyses of the Core Antenna Domain: Investigatingthe Origin of Photosystem I

Phototrophy, the conversion of light to biochemical energy, occurs throughout the Bacteria and plants, however, debate continues over how different phototrophic mechanisms and the bacteria that contain them are related. There are two types of phototrophic mechanisms in the Bacteria: reaction center type 1 (RC1) has core and core antenna domains that are parts of a single polypeptide, whereas reaction center type 2 (RC2) is composed of short core proteins without antenna domains. In cyanobacteria, RC2 is associated with separate core antenna proteins that are homologous to the core antenna domains of RC1. We reconstructed evolutionary relationships among phototrophic mechanisms based on a phylogeny of core antenna domains/proteins. Core antenna domains of 46 polypeptides were aligned, including the RC1 core proteins of heliobacteria, green sulfur bacteria, and photosystem I (PSI) of cyanobacteria and plastids, plus core antenna proteins of photosystem II (PSII) from cyanobacteria and plastids. Maximum likelihood, parsimony, and neighbor joining methods all supported a single phylogeny in which PSII core antenna proteins (PsbC, PsbB) arose within the cyanobacteria from duplications of the RC1-associated core antenna domains and accessory antenna proteins (IsiA, PcbA, PcbC) arose from duplications of PsbB. The data indicate an evolutionary history of RC1 in which an initially homodimeric reaction center was vertically transmitted to green sulfur bacteria, heliobacteria, and an ancestor of cyanobacteria. A heterodimeric RC1 (=PSI) then arose within the cyanobacterial lineage. In this scenario, the current diversity of core antenna domains/proteins is explained without a need to invoke horizontal transfer.
Locus of control and expectancy in electromyographic biofeedback

Abstract From a subject pool of 226 psychology students, 16 external and 16 internal subjects, as determined by the Nowicki-Strickland Locus of Control Scale, were randomly assigned to either a positive or a negative expectancy group ( n =8). In Session I all subjects were asked to relax their frontalis muscle using auditory proportional biofeedback over 8 subsequent 3-min trials. The procedure was repeated during Session II except for the inclusion of a verbal expectation which suggested subjects' likelihood or non-likelihood of achieving further muscle relaxation. Results indicated that externals with positive expectancy had significantly higher levels of tension than internals with positive expectancy. No difference between externals and internals in the negative expectancy condition were observed. Results are interpreted to indicate that cognitive set affected the perception of performance ability with externals being disrupted by comments suggesting positive expectancies.
Design, Modeling, and Simulation of On-Demand Communication Mechanisms for Cyber-Physical Energy Systems

Advanced communication technology is the enabling factor for distributed sensing and control in smart grid. The performance of communication has a significant effect on the performance of the controllers that manage a power system. This effect is more profound when transient level behavior and critical applications are concerned. In these cases, an important issue is to design control-aware communication strategies for utilizing available communication technologies. Such strategies should describe what needs to be communicated when and between which nodes. In this paper, an “on-demand” strategy is presented that describes how communication subsystems should be configured, almost agnostically to the underlying technologies, to achieve significant performance improvement for the application. The on-demand method relies on the concept of error-dependent communication for tracking dynamical systems over communication networks. The paper also introduces the design of an embedded communication simulator integrated with PSCAD for cosimulation of communication strategies/protocols and power system components.
Postprandial exercise-induced anaphylaxis

Abstract A variety of systemic reactions associated with exercise are increasingly being recognized. We studied an atopic individual whose job-related activities involved strenuous running that often terminated in an episode of syncope and hypotension preceded by cutaneous pruritus, warmth, urticaria, and angioedema. These attacks occurred only after meals, but no foods appeared to elicit symptoms without subsequent exercise. The subject underwent three exercise challenges in the laboratory under the following conditions: (1) fasting state, with heat-dissipating clothing, (2) fasting, with heat-retention clothes, and (3) after a meal. Blood pressure decreases and minimum skin reactivity were observed for (1) and (2), and reproduction of syncope, hypotension, and further cutaneous manifestation were observed only after (3). Venous and arterial plasma determinations for complement activation (C4, C4d, and CH 50 ) and histamine before, during, and after exercise were not abnormal. Although other vasodepressor mediators may have been liberated, at least part of the mechanism for postprandial exercise-related syncope may be attributed to a shift of blood flow to the splanchnic as well as skeletal muscle vasculature.
Examination of the premelting transition of DNA A-tracts using a fluorescent adenosine analogue.

The fluorescent adenosine analogue 4-amino-8-(2-deoxy-β-d-ribofuranosyl)-5‘-O-dimethoxytrityl-6-methyl-7(8H)-pteridone (6MAP) has been used to perform residue specific analyses of DNA A-tracts during the premelting transition. DNA A-tracts, which exhibit sequence-induced curvature, adopt a B-DNA conformation as a function of increasing temperature. Fluorescence melting curves indicate that 6MAP is a more sensitive reporter of the premelting transition than UV absorption spectroscopy. Further, residue specific fluorescence analyses of A-tract and control duplexes reveal that some of the conformational changes associated with the premelting transition occur within A-tract regions. Analyses of the energetics of the premelting transition indicate that ApA steps make a larger enthalpic contribution to the premelting transition than ApT steps. To explore the effect of cations on the premelting transition, fluorescence melts were performed in the presence of NH4+, Mg2+, and low (0.05 M) and high (0.5 M) concentr...
Functional relation between infarct thickness and regional systolic function in the acutely and subacutely infarcted canine left ventricle

Abstract Specific information regarding the relation between infarct thickness and regional systolic function is important to the overall understanding of both the pathophysiology of acute and subacute myocardial infarction and the functional benefits of myocardial salvage interventions designed to limit the transmural extent of infarction and thereby preserve left ventricular function. In the present study, quantitative computer-assisted two-dimensional echocardiography was used to define the relation between infarct thickness and systolic function in the acutely and subacutely infarcted canine left ventricle. Echocardiograms were obtained at the mid-papillary muscle level at baseline and 6 h after occlusion (acute infarction) in eight animals and at baseline and 72 h after occlusion (subacute infarction) in nine animals. Systolic function was assessed by measuring the extent of fractional radial shortening along each of 36 evenly spaced endocardial targets from end-diastole to end-systole; the transmural extent of infarction was determined from the triphenyltetrazolium chloride-staining deficit at 6 and 72 h. The relation between systolic function and transmural extent of infarction was analyzed in two ways. First, the extent of fractional radial shortening in each group was examined as a function of quartile (25%) increments in transmural infarct thickness. This analysis revealed 1) a significant overall loss of fractional radial shortening with increasing transmural extent of infarction in both groups; and 2) significant differences in the extent of systolic dysfunction between successive quartile increments of infarction. Second, the relation between infarct thickness and systolic dysfunction was modeled mathematically by fitting the data from each infarct series to linear, logarithmic and exponential functions. This analysis revealed, for each animal tested, a significant downsloping linear relation between fractional shortening and transmural extent of infarction. Furthermore, the logarithmic and exponential curves generally modeled the data in a fashion indistinguishable from the linear function. Thus, this experimental study demonstrates for the first time a linear relation between the transmural extent of infarction and the extent of regional systolic dysfunction.
Using Triplex-Forming Oligonucleotide Probes for the Reagentless, Electrochemical Detection of Double-Stranded DNA

We report a reagentless, electrochemical sensor for the detection of double-stranded DNA targets that employs triplex-forming oligonucleotides (TFOs) as its recognition element. These sensors are based on redox-tagged TFO probes strongly chemisorbed onto an interrogating gold electrode. Upon the addition of the relevant double-stranded DNA target, the probe forms a rigid triplex structure via reverse Hoogsteen base pairing in the major groove. The formation of the triplex impedes contact between the probe's redox moiety and the interrogating electrode, thus signaling the presence of the target. We first demonstrated the proof of principle of this approach by using a well-characterized 22-base polypurine TFO sequence that readily detects a synthetic, double-stranded DNA target. We then confirmed the generalizability of our platform with a second probe, a 19-base polypyrimidine TFO sequence that targets a polypurine tract (PPT) sequence conserved in all HIV-1 strains. Both sensors rapidly and specifically detect their double-stranded DNA targets at concentrations as low as ~10 nM and are selective enough to be employed directly in complex sample matrices such as blood serum. Moreover, to demonstrate real-world applicability of this new sensor platform, we have successfully detected unpurified, double-stranded PCR amplicons containing the relevant conserved HIV-1 sequence.
COST FUNCTIONS FOR ADDITIONAL GROUND WATER DEVELOPMENT

Cost functions are determined which will allow compensation to existing users of ground water when new users require rights. These functions are dependent on the additional energy cost to existing users. The costs produced by these functions can be significant when large quantities of water are required.
Media coverage of police misconduct and attitudes toward police

Purpose – The purpose of this paper is to examine how celebrated cases affect attitudes toward police, controlling for key demographic, police contact, and neighborhood contextual variables.Design/methodology/approach – The paper presents two waves of public opinion data measuring attitudes toward police, police services, police harassment, and officer guilt before and after a celebrated police misconduct trial. Data were collected by telephone from residents living in three areas.Findings – The findings in the paper suggest that news consumption of this celebrated case had no significant effects on general attitudes toward police, police services, and concerns about police harassment. Media coverage, however, did effect citizen evaluation of the guilt of the officers involved in the case. The more a citizen read a newspaper or read about the case, the more likely she was to think that the officers were guilty. Concern about crime in the neighborhood was an important predictor of attitudes toward the poli...
Evaluating Teachers: A Call for Change

A standard model for evaluating teaching has been employed in our schools for decades (Boyce, 1915). In the vast majority of school districts, a nontenured teacher is observed twice a year, for a period of 20 to 30 minutes, by the building principal (Lower, 1987; Sweeney & Manatt, 1986). Tenured teachers are observed for approximately the same number of minutes, but less frequently. Sometimes a conference follows the observation where the principal's rote is to describe the strengths and weaknesses of the teacher's performance and offer suggestions for improvement (Haefcle, 1981). This dominant model of teacher evaluation is in trouble. Evaluation criteria lack validity. Evaluators are untrained. Evaluators consistently award lenient ratings to weak and incompetent teachers. These and other practices examined below clearly indicate that the current teacher evaluation model is seriously deficient (Haefele, 1992). Deeply entrenched in American schooling, any massive attempt to dump this model and start over appears unachievable. Inasmuch as school districts are unwilling to seek alternative procedures for evaluating teachers, the serious deficiencies should be identified and radically changed to improve the prevailing model. Areas where the most dramatic changes are essential are reviewed here.
Portfolio analysis with partial information: the case of grouped data

Almost all of the literature in finance analyzing the selection of optimum portfolios assumes that the agent making the decision has a full set of estimates of the expected return for each security and the variance covariance matrix between securities. In actual practice most decision makers simply receive a list of stocks with ranking on each stock and perhaps some partial risk information. The purpose of this paper is to determine what we can learn from portfolio theory about optimum decisions if all the investor knows is the grouping of stocks plus at best the average characteristics of the stocks in a group. This analysis is important because these are the data most investors utilize to make their portfolio decisions.
The dopamine-serotonin relationship in clozapine response

The effects of clozapine on the dopamine and serotonin systems may underlie its atypical pharmacologic and clinical profile. To examine this hypothesis, we measured dopamine and serotonin plasma and cerebrospinal (CSF) metabolites and the relationship of these values to treatment response in 19 neuroleptic refractory and intolerant schizophrenic patients. Only a small change in the CSF and plasma homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5HIAA) levels was found. However, the pretreatment CSF HVA/5HIAA ratio and, to a lesser extent, the CSF HVA level predicted treatment response. These results suggest that the modest relationship between HVA and 5-HIAA and treatment response supports the involvement of both neurotransmitters in the pathophysiology of schizophrenia.
Is energy expenditure in the hamster primarily under homeostatic or circadian control

1. In order to discriminate between homeostatic and circadian control of energy expenditure, this paper considers whether a shorter circadian cycle will produce a proportional reduction in energy expenditure (so that expenditure per unit time is conserved) or alternatively whether energy expenditure will be compressed into the shorter cycle (so that energy expenditure per cycle is conserved). To answer this question, we measured energy expenditure in tau mutant hamsters (whose free-running circadian period has been reduced to about 20 h by a single gene mutation) and wild-type hamsters (whose free-running circadian period is about 24 h). 2. In one experiment, the circadian rhythm of running-wheel activity of tau mutant hamsters was compared with that of wild-type hamsters. The rate of running was not affected by the mutation and, consequently, the total amount of activity per cycle was significantly less in mutants than in wild-type hamsters, whereas the total amount of activity per unit time was nearly the same. 3. In a second experiment, we measured energy expenditure by indirect calorimetry. Metabolic rate was not affected by the mutation and, consequently, the total amount of energy expended per cycle was significantly less in mutants than in wild-type hamsters but equivalent per unit time. 4. Because the amount of energy expenditure and locomotor activity was found to be proportional to the circadian cycle, we conclude that expenditure per unit time-rather than expenditure per circadian cycle-is conserved in the mutant animals. Therefore, we infer that energy expenditure in hamsters is primarily under homeostatic, not circadian, control. Further research is necessary to determine whether this inference can be applied to other species.
Self-assessed and functional health of older women.

Un echantillon de femmes âgees repond a un questionnaire d'autoevaluation sur leur sante, leur concept de soi, et leurs attitudes generales
A Theoretical Determination of the Capture Efficiency of Small Columnar Ice Crystals by Large Cloud Drops

Abstract A theoretical model has been formulated to study by numerical techniques the efficiency E with which columnar ice crystals grown at temperatures between −3 and −8°C are captured in a cloud by relatively large, supercooled cloud drops. The ice crystals studied had lengths L of 15 ≤ L ≤ 240 μm and diameters D of 1.5 ≤ D 240 μm. and L/D values of 1.0, 3.0 and 10.0. The specific gravity of the ice crystals was assumed to be 0.92 and 0.5 g cm−3. The cloud drops had Reynolds numbers of 10, 30, 100, −200, 300 and 400, corresponding to the drop radii rd of 100, 165, 300, 416, 510 and 591 μm in air at. 900 mb and −6°C. A few computations were made for 500 mb and −10°C. The ice crystals were assumed to have three typical, yet fixed, orientations with respect to the drop, in an attempt to take into account, in an idealized manner, the different orientations a columnar ice crystal assumes as it moves around a failing drop. It is found that a water drop of given size collects columnar ice crystals with an eff...
A theoretical analysis for the formation of periodic layered structure in ternary diffusion couples involving a displacement type of reactions

Abstract Periodic layered structures were found to form in numerous ternary diffusion couples of the type B δ′ C/A involving a displacement type of reactions. In all of these couples, A is a dominant diffusing species within the diffusion zone and C is essentially immobile. Occurrence of this type of layered structure was rationalized in terms of thermodynamic arguments. Moreover, a diffusion model was formulated to describe the growth of this structure. An appropriate solution to the diffusion equations was obtained when simplified assumptions were made. The relative stability of a periodic layered structure versus that of a simple layered structure is governed by the relative mobilities of A and B within the diffusion zone. The simple layered structure is formed when B has a high mobility relative to that of A. On the other hand, with increasing mobility of A, the periodic layered structure tends to be stable.
Demonstration of naturalistic methods for cocaine smoking by human volunteers.

Abstract Five, healthy, adult, male research volunteers participated in up to four daily laboratory sessions while residing on a Clinical Research Unit. Two subjects were tested twice. Fifty milligrams of cocaine base was smoked one, two or four times each session with a 14-min interval between doses. Two subjects smoked cocaine placed in ‘smoke-free’ cigarettes, while the remaining subjects smoked cocaine placed in a modified tobacco pipe. Significant and biologically relevant cocaine venous blood levels were engendered most consistently using the modified tobacco pipe. Large, transient increases in heart rate, blood pressure and self-reported ‘stimulated’ scores were observed during single dosing sessions. During multiple dose sessions, cardiovascular activity either increased, returning to near baseline levels between doses, or were sustained, while reported ‘stimulated’ scores peaked after the first dose and were lower following subsequent doses. Both cardiovascular and subjective effects were greater on the ascending limb than on the descending limb of the cocaine blood level curve suggesting acute tolerance. Although preliminary, these results demonstrate the usefulness of this relatively simple procedure requiring subjects to smoke in the manner they are accustomed, and suggest the importance of further research in this area.
Hypo-allergenic and therapeutic significance of goat milk

Abstract Pathogenesis of cow milk allergy indicates that multiple immunological mechanisms exist. Two types of food allergy reactions occur in infants, children and adults. They are reaginic (IgE mediated) or nonreaginic. About 7% of children in the US have symptoms of cow milk allergy, even though almost all children under age 3 yr have circulating milk antibodies. β-Lactoglobulin (molecular weight 36 000) is the major whey protein of cow milk, not found in human breast milk and mostly responsible for cow milk allergy. Clinical symptomology for patients allergic to bovine milk proteins include: rhinitis, diarrhea, vomiting, asthma, anaphylaxis, urticaria, eczema, chronic catarrh, migraine, colitis and epigastric distress. Goat milk has been recommended as a substitute for patients allergic to cow milk. Between 40 to 100% of patients allergic to cow milk proteins tolerate goat milk. Although some caprine milk proteins have immunological crossreactivity with cow milk proteins, infants suffering from gastrointestinal allergy and chronic enteropathy against cow milk were reportedly cured by goat milk therapy. The higher protein, nonprotein N and phosphate in caprine milk give it greater buffering capacity compared to cow milk. Some physico-chemical properties of caprine milk such as smaller fat globules, higher percent of short and medium chain fatty acids, and softer curd formation of its proteins are advantageous for higher digestibility and healthier lipid metabolism relative to cow milk. Goat milk also has a greater iron bioavailability in anemic rats than cow milk. Further studies of the hypoallergenic and therapeutic significance of goat milk to humans are very much needed.
Wide-angle breast tomosynthesis: initial comparative evaluation

Conventional mammography is largely limited by superimposed anatomy which is alleviated by breast tomosynthesis and CT. Limited acquisition in tomosynthesis can result in significant out of plane artifacts while large angular acquisition span in CT can limit the imaging coverage of the chest wall near the breast. We propose a new breast imaging modality, wide-angle breast tomosynthesis (WBT), aimed to provide a practical compromise between 3D sampling and chest-wall coverage. This study compares lesion detection between conventional digital breast tomosynthesis, WBT, and breast CT (44°, 99°, and 198° total angle range, respectively) under equal patient dose conditions. A Monte Carlo (MC) code based on the Penelope package modeled a virtual flat-panel breast tomosynthesis system. The modalities were simulated at four breast compression levels. Glandular dose to the breast was estimated and the radiation flux was subsequently adjusted to achieve a constant mean glandular dose level of 1.5 mGy, independent of the breast thickness and acquisition geometry. Reconstructed volumes were generated using iterative reconstruction methods. Lesion detectability was estimated using contrast-to-noise-ratio. Results showed improved detection with increased angular span and compression. Evaluations also showed improved performance of WBT over DBT at lower compression levels, therefore highlighting potential for reduced breast compression when using a larger acquisition angle.
Frank Elastic Constants of the Hard-Rod Liquid Crystal

The elastic constants of a hard-rod liquid crystal are calculated using the Onsager theory, with results similar to those given by Priest.
Corticotropin-releasing factor 1 antagonists selectively reduce ethanol self-administration in ethanol-dependent rats.

Background Alcohol dependence is characterized by excessive alcohol consumption, loss of control over intake, and the presence of a withdrawal syndrome, which includes both motivational and physical symptoms. Similar to human alcoholics, ethanol-dependent animals display enhanced anxiety-like behaviors and enhanced ethanol self-administration during withdrawal, effects hypothesized to result from a dysregulation of corticotropin-releasing factor (CRF) stress systems. Here, we used an animal model of ethanol dependence to test the effects of CRF 1 receptor antagonists on excessive ethanol self-administration in dependent rats. Methods Wistar rats, trained to orally self-administer ethanol, were exposed intermittently to ethanol vapors to induce ethanol dependence. Nondependent animals were exposed to control air. Following a 2-hour period of withdrawal, dependent and nondependent animals were systemically administered antalarmin, MJL-1-109-2, or R121919 (CRF 1 antagonists) and ethanol self-administration was measured. Results The nonpeptide, small molecule CRF 1 antagonists selectively reduced excessive self-administration of ethanol in dependent animals during acute withdrawal. The antagonists had no effect on ethanol self-administration in nondependent rats. Conclusions These data demonstrate that CRF 1 receptors play an important role in mediating excessive ethanol self-administration in dependent rats, with no effect in nondependent rats. CRF 1 antagonists may be exciting new pharmacotherapeutic targets for the treatment of alcoholism in humans.
Levels of soluble HLA-I and β2M in patients with acute myeloid leukemia and advanced myelodysplastic syndrome: Association with clinical behavior and outcome of induction therapy

beta-2 Microglobulin (beta2M), a subunit of human leukocyte antigen-class I (HLA-I), is well established as a marker of prognosis in various solid tumors and hematologic malignancies. The prognostic role of intact free-circulating HLA-I (sHLA-I) is less well understood. We compared the clinical relevance of plasma levels of sHLA-I and beta2M in patients with acute myeloid leukemia (AML; n=209) or advanced myelodysplastic syndrome (MDS; n=98). sHLA-1 and beta2M levels were significantly higher in AML and MDS patients than in control subjects, but did not differ significantly between the two disease groups. In AML patients, multivariate analysis showed both sHLA-1 and beta2-M to be highly predictive of complete remission (CR), survival and duration of complete response (CRD). In MDS, the predictive value of the two markers differed substantially from one another: beta2M was associated with survival, CR and CRD, whereas sHLA-I was not. These findings not only establish the role of sHLA-I as a tumor marker in AML but also support that MDS is clinically and biologically distinct from AML. sHLA-I has been reported to be an immunomodulator inhibiting the cytotoxic effects of T-lymphocytes, which may offset its predictive value for disease aggressiveness in patients with MDS.
A FIRE-ACE/SHEBA Case Study of Mixed-Phase Arctic Boundary Layer Clouds: Entrainment Rate Limitations on Rapid Primary Ice Nucleation Processes

Observations of long-lived mixed-phase Arctic boundary layer clouds on 7 May 1998 during the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE)‐Arctic Cloud Experiment(ACE)/SurfaceHeatBudgetoftheArcticOcean(SHEBA)campaignprovideauniqueopportunity to test understanding of cloud ice formation. Under the microphysically simple conditions observed (apparently negligible ice aggregation, sublimation, and multiplication), the only expected source of new ice crystals is activation of heterogeneous ice nuclei (IN) and the only sink is sedimentation. Large-eddy simulations with size-resolved microphysics are initialized with IN number concentration NIN measured above cloudtop,butdetailsofINactivationbehaviorareunknown.Ifactivatedrapidly(indeposition,condensation,
Cat allergen 1: Biochemical, antigenic, and allergenic properties

Abstract Cat allergen 1, an important agent in human allergic reactions, has been partially purified by affinity chromatography. Heating the purified allergen at 100 ° C for 30 min resulted in a 28% loss in the antigenicity of the allergen molecule (determined by Laurell rocket assay), although lower temperatures had little effect. Its allergenicity (determined by passive transfer skin test) was diminished slightly after heating to 56 ° or 100 ° C. Reduction with dithiothreitol or 2-mercaptoethanol resulted in greater losses of antigenicity and allergenicity but did not obliterate these properties. Three forms of the affinity-purified allergen (isoallergens) differing slightly in isoelectric point were demonstrated by isoelectric focusing followed by crossed immunoelectrophoresis. The molecular weight of cat allergen 1 under physiologic conditions was 35,000 ± 2000 as determined by gel filtration in Sephadex G-75. Under the dissociative conditions of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with or without prior reduction by dithiothreitol, cat allergen 1 appeared to exist as an antigenically active subunit with a molecular weight of 18,000 ± 2000. This subunit molecular weight estimate was confirmed by gel filtration in 6M guanidine hydrochloride. The stability of the allergenic and antigenic activity of cat allergen 1 suggests that this activity may be determined partially by the primary sequence of allergenic sites on the molecule. The separation ond purification of molecular subunits may allow sequence analysis of these sites.
Increased tumorigenicity in the human pancreatic cell line MIA PaCa‐2 Is associated with an aberrant regulation of an IGF‐1 autocrine loop and lack of expression of the TGF‐β type RII receptor

The growth characteristics associated with tumorigenicity were determined in clones of MIA PaCa-2 and PANC-1 pancreatic carcinoma cells. MIA PaCa-2 cells differed from PANC-1 cells in that they rapidly formed tumors in nude mice, formed colonies more rapidly and formed larger colonies in soft agar, and were cloned more efficiently when seeded at low density. MIA PaCa-2 cells but not PANC-1 cells were stimulated to escape quiescence and undergo DNA synthesis with nutrient media lacking growth factors. Both cell lines were stimulated to proliferate with serum-free media containing EGF, transferrin, and insulin. Antibody neutralization assays indicated that an IGF-1 autocrine loop was required for the nutrient stimulation of growth in MIA PaCa-2 cells and for the growth-factor stimulation in both MIA PaCa-2 and PANC-1 cells. Both cell lines were stimulated to proliferate with exogenous IGF-1 in basal media; this stimulation was specifically blocked by antibodies to IGF-1 or its receptor. MIA PaCa-2 and PANC-1 cells expressed similar levels of IGF-1 receptor mRNA and showed similar binding kinetics in receptor binding assays. In contrast to PANC-1 cells, MIA PaCa-2 cells were insensitive to TGF-beta 1 and did not express TGF-beta receptor type II. The results suggest that the growth-factor independence is representative of a more tumorigenic phenotype. We hypothesize that growth-factor independence of MIA PaCa-2 cells is mediated by an aberrant regulation of an IGF-1 autocrine loop. A decreased regulation of this IGF-1 loop may be potentiated by loss of response to TGF-beta.
Observations of231Pa/235U disequilibrium in volcanic rocks

Abstract We present here the first survey of (231Pa/235U) ratios in volcanic rocks; such measurements are made possible by new mass spectrometric techniques. The data place new constraints on the timing and extent of magma source and evolutionary processes, particularly due to the sensitivity of the231Pa-235U pair and its intermediate time scale (231Pat1/2 = 33 ky). (231Pa/235U) is found to vary widely, from 0.2 in carbonatites to 1.1–2.9 in basalts and 0.9–2.2 in arcs. Substantial Pa enrichment is nearly ubiquitous, suggestive of the relative incompatibility of Pa, qualitatively consistent with available partitioning data. The level of231Pa-235U disequilibrium typically far exceeds that of230Th-238U and is comparable to226Ra-230Th. The high (231Pa/235U) ratios in MORB and other basalts reflect a large degree of discrimination between two incompatible elements, posing challenges for modelling of melt generation and migration. Fundamental differences in (231Pa/235U) among different basaltic environments are likely related to contrasts in melting zone conditions (e.g., melting rate). Strong (231Pa/235U) disequilibria in continental basalts, for which (230Th/238U) disequilibria are small or absent, demonstrate that Pa-U fractionation is possible in both garnet and spinel mantle stability fields. In arcs, correlation of (231Pa/235U) and (230Th/238U) is consistent with U enrichment via slab-derived fluids, a process which is additional to the still dominant Pa enrichment. An important new constraint is provided by the observation that the near-equilibrium (230Th/238U) common to arcs and continental basalts is not typically accompanied by near-equilibrium (231Pa/235U), arguing against the influence of long magma history, crustal material, or equilibrium mantle sources in affecting decay-series ratios. Small sample sets from two silicic centers illustrate: (1) recent, rapid U enrichment in the magma chamber (El Chichon); and (2) the failure of substantial magma H2O-CO2 degassing to effect U-Th-Pa fractionation (Mono Craters).