cssi/SciSciGPT-SciSciNet huggingface dataset:
Density and dose: factors affecting mortality of Streptococcus iniae infected tilapia /Oreochromis niloticus

Fish density and infectious dose have been suspected to affect the mortality rate of cultured fish exposed to Streptococcusiniae. We determined the effects of S. iniae dose and tilapia (Oreochromisniloticus) density on streptococcal disease mortality. Tilapia with a mean weight of 12.7 g were used and maintained at 25±1°C in aquaria supplied with flow-through water at 0.5 l/min with a 12 h light:12 h dark cycle. Density and dose were evaluated by stocking tilapia at low (5.6 g/l), medium (11.2 g/l) and high (22.4 g/l) density and administering 2.5×107, 5×107 and 1×108 colony-forming units (CFU)/ml of S. iniae by immersion (5 tanks per density and dose, 45 total tanks). Mortality was monitored for 28 days post challenge. A significant difference (P<0.05) was seen in mortality when comparing low (4.8%) and medium (28.4%) and low and high (25.6%) density treatments. No significant difference was observed when comparing medium- and high-density treatments. Two-way analysis of variance demonstrated density had a significant effect on S. iniae mortality (P=0.0001). Doses had little effect on mortality, except at high density by dose which did show a significant interaction (P=0.001). We have demonstrated density has a significant effect on streptococcal disease mortality in tilapia exposed to S. iniae by immersion. We also evaluated infection of susceptible tilapia using dead/moribund S. iniae infected fish (i.e., cohabitation by placing five dead/moribund fish into tanks for 48 h). No significant difference in mortality pattern was observed between immersion in 8.6×107 CFU/ml S. iniae (37.6% and 34.6%) and cohabitation with S. iniae infected tilapia (24.0%). Although, densities used were less than in most water-reuse production systems (30–290 g/l), tilapia density of 11.2 g/l and above was an important factor in mortality of tilapia infected with S. iniae. A health-management strategy would be to reduce fish density thus lowering streptococcal disease mortality.
Prospective teacher learning: recognizing evidence of conceptual understanding

This study examined prospective teachers’ (PSTs) ability to recognize evidence of children’s conceptual understanding of mathematics in three content areas before and after an instructional intervention designed to support this ability. It also investigates the role PSTs’ content knowledge plays in their ability to recognize children’s mathematical understanding. Results of content knowledge assessments administered at the beginning of the study revealed that content knowledge did seem to support PSTs’ analyses of children’s understanding when the child’s response demonstrated understanding or demonstrated a misconception. Content knowledge did not seem to support PSTs’ analyses of children’s procedural responses, as many PSTs with good content knowledge initially characterized procedural solutions as evidence of conceptual understanding. Similarly, content knowledge did not seem to support PSTs’ analyses of children’s responses with features commonly associated with understanding but not evidence of understanding. After the instructional intervention consisting of three multifaceted lessons in which PSTs examined many examples of student thinking, they showed improved ability to analyze responses with conceptual features and no evidence of conceptual understanding and responses demonstrating procedural knowledge. Results suggest that content knowledge is not sufficient for supporting PSTs’ analysis of children’s thinking, and that building activities such as the intervention into content courses may help develop this ability. Implications for teacher education programs and future research are considered.
Feeling and learning about a critical event: The shuttle explodes

This study examines the feelings, learning, and diffusion effects resulting from the Challenger explosion using a two pronged approach both in a cross‐section and an over‐time panel design. The sam...
Coronary heart disease risk factors and atherosclerosis in young people

Atherosclerosis begins in childhood or adolescence and progresses during the young adult years to cause clinical coronary heart disease (CHD) in middle-aged and older individuals. This article reviews evidence regarding the association of the major established CHD risk factors with atherosclerosis in adolescents and young adults, with emphasis on the findings of the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) study. Age, non-high-density lipoprotein cholesterol concentration, smoking, hypertension, obesity, and hyperglycemia are positively associated with atherosclerotic lesions, whereas female gender and high-density lipoprotein cholesterol concentration are negatively associated with lesions. The PDAY study developed a risk score that provides a weighted summary of the risk factor effects on advanced atherosclerosis. Although developed to predict advanced atherosclerotic lesions, the risk score is also associated with all stages of lesion severity, including the transition from normal tissue to the earliest anatomically detectable lesion. Application of the PDAY risk score to data from longitudinal studies of risk factors in young adults shows that early measurement of risk factors predicts atherosclerosis assessed noninvasively up to 15 years later, and that subsequent change in risk score during the 15-year interval also predicts atherosclerosis. These findings provide strong support for maintaining a low lifetime risk and for focusing on preventing atherosclerosis as the most effective way to prevent CHD. Risk-factor control beginning in the late teenage years will retard development of the earliest stage of atherosclerosis and its progression, and will reduce or delay occurrence of CHD.
Changes in noradrenergic terminal excitability induced by amphetamine and their relation to impulse traffic.

Abstract The effects of amphetamine upon the terminal excitability of noradrenergic neurons of the nucleus locus coeruleus were studied in urethane anesthetized rats. Terminal excitability was measured by determining the stimulus currents necessary to evoke antidromic responses in locus coeruleus neurons from terminals in the frontal cortex. In most cases, terminal excitability was decreased following local infusion of amphetamine into the frontal cortex, while intravenous administration of the drug tended to increase terminal excitability. The decreased terminal excitability induced by local infusion of amphetamine appeared to be due to activation of alpha-adrenergic receptors located on the terminals of locus coeruleus neurons, since this effect mimics that of clonidine, a direct acting alpha-adrenergic agonist, and since the effect was abolished by pretreatment withalpha-methyl- p -tyrosine which disrupts the catecholamine liberating properties of amphetamine. Phentolamine, a direct acting alpha-adrenergic receptor antagonist was also found to block or reverse the effect of amphetamine. The changes in terminal excitability following intravenous injection of amphetamine appeared to be related to changes in the spontaneous activity of locus coeruleus neurons. A large decrease in spontaneous activity following intravenous administration of amphetamine was associated with increased terminal excitability, whereas when smaller changes in spontaneous activity occurred, terminal excitability was found to be decreased. These results are discussed with respect to the pharmacological properties of catecholaminergic neurons and the mechanisms of action of amphetamine.
Evidence for iron channeling in the Fet3p-Ftr1p high-affinity iron uptake complex in the yeast plasma membrane

In high-affinity iron uptake in the yeast Saccharomyces cerevisiae, Fe(II) is oxidized to Fe(III) by the multicopper oxidase, Fet3p, and the Fe(III) produced is transported into the cell via the iron permease, Ftr1p. These two proteins are likely part of a heterodimeric or higher order complex in the yeast plasma membrane. We provide kinetic evidence that the Fet3p-produced Fe(III) is trafficked to Ftr1p for permeation by a classic metabolite channeling mechanism. We examine the (59)Fe uptake kinetics for a number of complexes containing mutant forms of both Fet3p and Ftr1p and demonstrate that a residue in one protein interacts with one in the other protein along the iron trafficking pathway as would be expected in a channeling process. We show that, as a result of some of these mutations, iron trafficking becomes sensitive to an added Fe(III) chelator that inhibits uptake in a strictly competitive manner. This inhibition is not strongly dependent on the chelator strength, however, suggesting that Fe(III) dissociation from the iron uptake complex, if it occurs, is kinetically slow relative to iron permeation. Metabolite channeling is a common feature of multifunctional enzymes. We constructed the analogous ferroxidase, permease chimera and demonstrate that it supports iron uptake with a kinetic pattern consistent with a channeling mechanism. By analogy to the Fe(III) trafficking that leads to the mineralization of the ferritin core, we propose that ferric iron channeling is a conserved feature of iron homeostasis in aerobic organisms.
Capital One's statistical problems: our top ten list

Capital One is a highly quantitatively driven diversified financial services firm. As such, we make broad and deep use of the entire repertory of highly quantitative techniques. This talk will present our top ten statistical problems. Indeed, one of them has, as a sub point, the data mining dimension, but it will likely be useful for data miners to see how their research needs to complement, and fit into, the entire range of hard statistical issues.
Choosing between the New Cephalosporin Antibiotics

The use of pharmacodynamic properties when formulating antibacterial administration guidelines can maximise the potential for efficacy while minimising the risk of toxicity. Aminoglycosides and quinolones demonstrate concentration-dependent bactericidal killing, which is maximised when their concentrations appreciably exceed their minimum inhibitory concentration (MIC) for an organism. (s-Lactams demonstrate time-dependent or concentration-independent bactericidal killing, which is maximised when the time that concentrations exceed the MIC is prolonged, regardless of the absolute levels attained. Methods of prolonging the time s-lactam concentrations exceed the MIC include the following: interfering with excretion (e.g. probenecid); decreasing the dosage interval; increasing the dose; infusing continuously rather than by bolus; and choosing an agent with a prolonged elimination half-life. The optimal duration for exceeding the MIC varies with the infecting organism, site of infection, inoculum effect, and the immuno-competence of the host. Integration of the microbiological activity and pharmacokinetic properties enables estimation of the time that serum concentrations of various cephalosporins will exceed the MIC of a given organism, consequently allowing estimation of the relative potential for clinical success. Cefixime, a third generation oral cephalosporin with a long plasma elimination half-life, allowing once-daily administration, achieves serum concentrations that exceed the MIC of Haemophilus influenzae, Moraxella catarrhalis, Escherichia coli, and Group A streptococci for > 90% of the dosage interval, and the MIC of Streptococcus pneumoniae for 50 to 90% of the dosage interval.
Pathological worry in major depression: a preliminary report

Forty-nine Ss with the DSM-III-R generalized anxiety disorder (GAD) and 32 Ss with the DSM-III-R major depressive episode (MDE) were administered the Penn State Worry Questionnaire (PSWQ) in order to assess the frequency and severity of worrying. The PSWQ scores were almost equally elevated in Ss with GAD and MDE, indicating that high PSWQ scores may not be specific for the diagnosis of GAD. This finding also suggests that except for the uncontrollability of worry, which was not measured by the PSWQ, there may be no difference in the process of pathological worrying between Ss with GAD and MDE. The domains of worry may or may not be similar in Ss with GAD and MDE, but the experiences associated with them are likely to be different, due to different cognitive schemata in anxiety and depression. Finally, the phenomenological presentation of pathological worry may also differ in these two conditions, which calls for further research in this area.
Acoustic thermometry data compared with two ocean models: the importance of Rossby waves and ENSO in modifying the ocean interior

Abstract An interpretation is made of interannual changes in acoustic travel time between Oahu and seven receivers at distances of 3000–4000 km. Measurements were made in late 1983, and over two 5-month intervals between 1987 and 1989. Previous publications demonstrated that these changes stem from variations in temperature. Two hydrodynamic ocean models are used to identify plausible oceanic features that could cause these variations. They are from the Naval Research Laboratory and the Florida State University at (1/8)° and (1/6)° resolution, respectively, and are forced with different interannual wind sets for more than a decade. Modelled El Nino's and La Nina's generate poleward travelling Kelvin waves on the eastern boundary of the Pacific. These excite Rossby waves that propagate westward at mid-latitudes. Rossby waves are the dominant model features which affect the modelled acoustic travel times, and hence section-averaged temperatures in the eastern North Pacific. These waves yield travel times whose standard deviations and rates of changes are similar to the measurements. In the observations, some sections separated by less than 500 km exhibit trends in heat content with opposite signs. Similar variability can be explained with modelled Rossby waves. Model wavelengths less than 500 km, eddies, and seasonal cycles induced by seasonal winds yield travel times that are two orders of magnitude too small to account for the data.
Serum Nitric Oxide Levels in Neonatal Infants with Bronchopulmonary Dysplasia and Respiratory Distress Syndrome

Serum Nitric Oxide Levels in Neonatal Infants with Bronchopulmonary Dysplasia and Respiratory Distress Syndrome
The E75 gene of Manduca sexta and comparison with its Drosophila homolog

The ecdysone-inducible E75 gene responsible for the 75B puff of Drosophila melanogaster encodes a family of proteins which are members of the steroid receptor superfamily. These proteins are believed to be involved in the regulation of ecdysone response. In order to investigate the evolutionary conservation of E75, we have identified the E75 gene of Manduca sexta. We show here the structure of a cDNA believed to encode the Manduca homolog of the E75 B protein, and demonstrate that the putative DNA binding, hormone binding and amino and carboxy terminal flanking domains are conserved. However, due to a relative reduction in intron size and number and the absence of homopolymeric amino acid repeats, the E75 B transcription unit and protein are considerably smaller in M. sexta than in D. melanogaster. These findings have implications for the identification of critical structural features of E75 and also suggest that E75 has a conserved function and a shared ligand in Lepidoptera.
Plessy in Perspective: Lofgren's View

In retrospect, the decisions of the U.S. Supreme Court during the 1890s may be viewed as a watershed of American constitutional development during which were implanted the theoretical seeds of many subsequent major constitutional controversies. For during the 1890s, the nation witnessed a resurgence of federal judicial power that was to result in the assumption by the Supreme Court and the federal judiciary of a more central role in national policy making than they had ever before assumed. Perhaps most symbolic of the new role of the federal judiciary on the national scene was the invalidation of the income tax by the Supreme Court in 1895,1 a decision that was only reversed by the adoption of the Sixteenth Amendment to the Constitution some 18 years later. Of more long-lasting significance, however, was the Supreme Court's broadening of the meaning of due process, especially under the Fourteenth Amendment, with the concomitant stretching of federal judicial power that that development entailed. In Chicago, Milwaukee & St. Paul Railroad Co. v. Minnesota,2 the Court thus indicated that the reasonableness of a railroad rate-and by implication the reasonableness of state legislation generally-was ultimately a judicial question to be resolved by the interpretation of the due process clause of the Fourteenth Amendment. Additionally, in such cases as AUgeyer v. Louisiana,3 the Court further broadened the meaning of due process by redefining the rights protected thereunder. The liberty of which individuals could not be deprived without due process of law, the Court said in AUgeyer and other cases, covered the limited
Continuous deep sedation until death: palliation or physician-assisted death?

Published literature have not discerned end-of-life palliative versus life-shortening effects of pharmacologically maintaining continuous deep sedation until death (ie, dying in deep sleep) compare...
Carbon dioxide exchange across the walls of arterioles: Implication for the location of the medullary chemoreceptors

The location of the medullary chemoreceptors is not conclusively established. The original experiments, which were believed to suggest a shallow surface location in the ventrolateral medulla, have been questioned because substances, particularly CO2, applied on the surface of the medulla could diffuse into small arterioles. Because the whole tissue blood flow is supplied by surface arterioles, they could transport substances from the surface into the tissue to the respiratory centers. We studied simple transport equations describing movement of CO2 in arterioles bathed by rapidly flowing cerebrospinal fluid (CSF) and arterioles in tissue perfused by capillaries. Substantial exchange of CO2 could occur across the arteriole wall for all expected sizes of vessels when the partial pressure of CO2 at the outside wall was determined by CSF. When an arteriole is surrounded by tissue, only vessels with inside diameters (ID)≲50 μm will exchange substantial amounts of CO2 but the smallest arterioles may be nearly in equilibrium with the tissue. The CO2 gradient in tissue around the arteriole will extend ∼ 1 mm. Our simple theoretical description of CO2 transport in arterioles predicts substantial exchange in precapillary vessels. CO2 picked up by the smallest surface arterioles when the medulla is perfused at a high rate with CSF will not stay in the blood past the putative depth of the chemoreceptors. In arterioles>30 μm, however, the CO2 could be carried to the respiratory centers.
Radionuclide carriers for targeting of cancer

This review describes strategies for the delivery of therapeutic radionuclides to tumor sites. Therapeutic approaches are summarized in terms of tumor location in the body, and tumor morphology. These determine the radionuclides of choice for suggested targeting ligands, and the type of delivery carriers. This review is not exhaustive in examples of radionuclide carriers for targeted cancer therapy. Our purpose is two-fold: to give an integrated picture of the general strategies and molecular constructs currently explored for the delivery of therapeutic radionuclides, and to identify challenges that need to be addressed. Internal radiotherapies for targeting of cancer are at a very exciting and creative stage. It is expected that the current emphasis on multidisciplinary approaches for exploring such therapeutic directions should enable internal radiotherapy to reach its full potential.
The action of dietary phytochemicals quercetin, catechin, resveratrol and naringenin on estrogen-mediated gene expression.

Abstract Hepatic expression of apolipoprotein (apo) II is in part modulated by estrogen-mediated stabilization of its mRNA. This stabilization is due to the estrogen-regulated mRNA stabilizing factor (E-RmRNASF) expressed in the liver in response to estrogen (Ratnasabapathy, 1995, Cell. Mol. Biol. Res, 41: 583–594). E-RmRNASF protects the RNA from targeted endonucleolytic degradation. The hepatic expression of E-RmRNASF is modulated by certain estrogenic and antiestrogenic nonsteroidal environmental xenobiotics (Ratnasabapathy et al. 1997, Biochem. Pharmacol., 53: 1425–1434). To determine whether dietary phytochemicals purported to prevent hormone-dependent breast and prostate cancers, and atherosclerosis, acted via the estrogen-cell-signaling pathway, roosters were administered increasing doses up to 1 mmole/kg of resveratrol, quercetin, catechin or naringenin parenterally and tested for hepatic expression of E-RmRNASF. Besides estrogen, the expression of E-RmRNASF in the liver was stimulated by resveratrol and catechin, indicating these agents to be estrogenic. A lack of E-RmRNASF expression was seen with the roosters treated with the vehicle, naringenin or quercetin. To determine whether the agents exerted partial agonistic or antagonistic effects, roosters were administered combinations of estrogen and increasing doses of the above phytochemicals. Resveratrol showed agonistic activity at all concentrations (10–1000 μmol./kg) tested. Catechin showed partial agonistic activity, while quercetin and naringenin appeared to be antagonistic.
Generalization of Büttiker-Landauer characteristic barrier interaction times to an arbitrary point within a barrier

Abstract Using a variety of approaches, Buttiker and Landauer have derived characteristic barrier interaction times for the transmission of particles completely across a rectangular potential barrier. We propose a generalization of these characteristic times to any point within an arbitrary barrier and present calculated results for a rectangular barrier with and without a multiple image potential correction.
Differential Effects of Selenium on Benign and Malignant Prostate Epithelial Cells: Stimulation of LNCaP Cell Growth by Noncytotoxic, Low Selenite Concentrations

We examined the hypothesis that nontoxic concentrations of selenium induce apoptosis and growth inhibition selectively in prostate cancer cells but not in benign prostate cells. Nontumorigenic BPH-1 prostate epithelial cells, androgen-sensitive LNCaP, and androgen-independent PC-3 prostate cancer cells were exposed to sodium selenite at 1 to 10 μ mol/l for 24 to 72 h. Cell proliferation, viability, and apoptosis were assessed by MTT assay, trypan blue exclusion, flow cytometry, DNA laddering, and caspase activation. BPH-1 cells were more sensitive for cytotoxic selenium effects than malignant prostate cells, whereas LNCaP cells were more sensitive than PC-3 cells. At noncytotoxic selenium concentrations, there was no apoptosis in BPH-1 and PC-3 cells and no growth inhibition of LNCaP and BPH-1 cells. PC-3 cells were refractory to apoptosis induction but were growth inhibited at noncytotoxic concentrations. LNCaP cells were growth stimulated at 1 μ mol/l and sensitive to apoptosis induction at higher noncy...
Commensal DNA limits regulatory T cell conversion and is a natural adjuvant of intestinal immune responses

The intestinal tract is in intimate contact with the commensal microflora. Nevertheless, how commensals communicate with cells to ensure immune homeostasis is still unclear. In this study, we found that gut flora DNA (gfDNA) plays a major role in intestinal homeostasis through Toll-like receptor 9 (TLR9) engagement. Tlr9(-/-) mice displayed increased frequencies of CD4(+)Foxp3(+) regulatory T (Treg) cells within intestinal effector sites and reduced constitutive IL-17- and IFN-gamma-producing effector T (Teff) cells. Complementing this, gfDNA limited lamina propria dendritic cell-induced Treg cell conversion in vitro. Further, Treg/Teff cell disequilibrium in Tlr9(-/-) mice led to impaired immune responses to oral infection and to oral vaccination. Impaired intestinal immune responses were recapitulated in mice treated with antibiotics and were reversible after reconstitution with gfDNA. Together, these data point to gfDNA as a natural adjuvant for priming intestinal responses via modulation of Treg/Teff cell equilibrium.
Optical communication with two-photon coherent states--Part III: Quantum measurements realizable with photoemissive detectors

In Part I of this three-part study it was shown that the use of two-photon coherent state (TCS) radiation may yield siginificant performance gains in free-space optical communicatinn if the receiver makes a quantum measurement of a single field quadrature. In Part II it was shown that homodyne detection achieves the same signal-to-noise ratio as the quantum field quadrature measurement, thus providing a receiver which realizes the linear modulation TCS performance gain found in Part I. Furthermore, it was shown in Part il that ff homodyne detection does exactly correspond to the field quadrature measurement, then a large binary communication performance gain is afforded by homodyne detection of antipodal TCS signals. The full equivalence of honmdyne detection and single-quadrature field measurement, as well as that of heterodyne detection and two-quadrature field measurement, is established. Furthermore, a heterodyne configuration which uses a TCS image-band oscillator in addition to the usual coherent state local oscillator is studied. This coafiguration termed TCS heterodyne detection is shown to realize all the quantum measurements described by arbitrary TCS. The foregoing results are obtained by means of a representation theorem which shows that photoemissive detection realizes the photon flux density measurement.
SCHOOL-BASED CORPORAL PUNISHMENT PRESENTING AS EXERCISE INDUCED RHABDOMYOLYSIS 1782

As of 1994, corporal punishment in schools is prohibited in 27 American states including New York State. Two boys, aged 11and 12 years, developed rhabdomyolysis from excessive exercise used as corporal punishment they received in a New York City public school. Both boys were ordered to perform 150 push-ups by their gymnastics teacher as a punishment for running around the gymnasium. Both developed tender and swollen deltoid and pectoralis major muscles and both required hospitalization for five days for parenteral hydration and urinary alkalinization to prevent acute renal failure. Serum levels of creatine kinase (CK), aminotransferases (AST, ALT), lactate dehydrogenase (LDH), and urine myoglobin (Ur Myoglobin) are shown below:Table After educational intervention, school officials responded with a new policy that no student perform more than six push-ups at any one time. As demonstrated here, corporal punishment in schools still endangers the health of children even in those states where it is illegal. Pediatricians can contribute to the abolishment of corporal punishment by: (1) educating him/herself that it is still legal in many American states, (2) promoting public awareness, (3) educating school officials and parents regarding alternatives, such as positive reinforcement for good behavior, (4) detecting and reporting cases of such punishment in schools and encouraging parents to utilize their rights to request that their children not be punished, and (5) educating school personnel and parents about the potential adverse effects of excessive exercise.
Elena Malvezzi's keyboard manuscript: a new sixteenth-century source*

It is safe to say that the collections of the Museo Comunale Bardini, situated in Piazza dei Mozzi on the oltrarno in Florence, remain comparatively little known. The museum's vast store of paintings, sculpture, architectural ornament, rugs and tapestries, armour, bronzes, furniture and musical instruments all belonged to Stefano Bardini, the nineteenth- and early twentieth-century collector and art dealer. Born in 1836 in the province of Arezzo, Bardini came to Florence to study painting at the Accademia delle Belle Arti. After the political turbulence of the 1860s, when Bardini fought with the Garibaldini, the young painter turned to restoration, connoisseurship and art dealing. By the age of forty-five he had established his reputation and an extraordinary personal collection. At the height of his career his patrons included the Rothschilds, the Vanderbilts, Isabella Gardiner and J. Pierpont Morgan. Many objects now in some of the world's best-known public collections passed through his hands.
Effects of fluid shear on immobilized enzyme kinetics.

Abstract There have been a number of reports concerning the damaging effects of shear on globular proteins in solution. Some recent work has indicated, however, that globular proteins in solution are relatively stable, but may be inactivated at air-liquid interfaces during shearing. This study investigated the effects of fluid shear on immobilized enzyme activity. Immobilized enzyme reactors were built to operate with the enzyme immobilized at the boundary of a fluid flow field. Two different enzymes, penicillinase and lactate dehydrogenase, were covalently bound to the interior surface of nylon tubes. Fluid shear rate was changed by varying the flow rate of substrate (reactant) solution through the tube, and fluid shear stresses were increased by increasing the viscosity of the recirculating solution. There were no observed effects of fluid shear on immobilized penicillinase or lactate dehydrogenase activity at shear rates of up to 10,350 s−1 or at shear stresses of up to 73 Pa.
Scientific computation: An interdisciplinary approach at Minnesota

This paper summarizes the welcoming talk at the Symposium on High-Performance Computer Applications in the Behavioral Sciences. It provides a brief overview of selected activities in scientific computation at the University of Minnesota Supercomputer Institute. These activities include international symposia and a graduate degree program.
Quantum electrodynamic effects in atomic structure

In high-Z atoms, quantum electrodynamic (QED) corrections are an important component in the theoretical prediction of atomic energy levels. The main QED effects in electronic atoms are the one-electron self-energy and vacuum-polarization corrections which are well known. At the next level of precision, estimates of the effect of electron interactions on the self energy and higher-order effects in two exchanged photon corrections are necessary. These corrections can be evaluated within the framework of QED in the bound interaction picture. For high-Z few-electron atoms, this approach provides a rapidly converging series in 1/Z for the corrections, which is the generalization of the well-known relativistic 1/Z expansion methods. This paper describes recent work on the effect of electron interactions on the self energy. The QED effects are particularly important for the theory for lithiumlike uranium where an accurate measurement of the Lamb shift has been made, as well as for numerous other cases where systematic differences appear between theory that does not include these QED effects and experiment.
Adoption of and experience with e-prescribing by primary care physicians

Abstract Background The impetus of electronic prescribing (e-prescribing) is the reduction of preventable medication errors by generating a legible prescription checked via e-prescribing software for drug-drug and other interactions. Although the adoption of e-prescribing among physicians is growing, the Institute of Medicine's recommendations that all prescriptions be routed electronically by 2010 certainly has not been met. Objectives To provide an update on e-prescribing use among primary care physicians (PCPs), describe their experience with e-prescribing, and provide insight into prescribers' decisions to implement e-prescribing in their practices. Methods An Internet-based survey was administered to a national convenience sample of physicians. The respondents were categorized into e-prescribers or non-e-prescribers. Data to describe demographic characteristics, respondents' experiences with e-prescribing, and respondents' decision to implement e-prescribing were collected. Nonparametric tests were used to test differences in the factors influencing e-prescribers' and traditional prescribers' decisions about electronic prescription implementation. Results Four hundred forty-three PCPs participated in the study. There were no significant differences in the demographic characteristics of e-prescribers and non-e-prescribers. Most e-prescribers (83%) reported satisfaction with their e-prescribing system and a preference for e-prescribing over traditional prescribing. Although 22% of respondents indicated that they have started and stopped e-prescribing, most have resumed or intended to resume e-prescribing in the near future. More than half of the respondents reported that they are experiencing problems with their e-prescribing software. Conclusions E-prescribing appears to be present in many types of primary care practices and geographic areas of the country. Despite their satisfaction with and preference for e-prescribing, PCPs still appear to be experiencing problems with e-prescribing software. Implications of these study results for the pharmacy profession are discussed.
Ant foraging activity in tropical agro-ecosystems.

Abstract The potential role of ants as biological control agents has been investigated in Mexican tropical agro-ecosystems. Ant predation is compared among plots planted in corn, bean, squash polycultures; bean and corn monocultures; and fallow fields. A second treatment, length of time of field cultivation, was also tested for each planting regime. All plot treatments reflect present agricultural practices in Mexico. Effectiveness of ant predation in each plot is measured experimentally as the rate of bait removal by ants. Bait removal by ants is significantly different among polycultures cultivated for various lengths of time. Bait removal is significantly different in old polycultures compared with the second-growth area suggesting that a select subset of the ant community may colonize polycultures. Since there are differences in ant foraging activity, it should be possible to enhance the effectiveness of ant predation in these agro-ecosystems.
DIFFERENTIALLY RELATING FACTORS OF LOCUS OF CONTROL TO A BEHAVIORAL CRITERION

Summasy.-A recenr factor analysis of scores on the Rotter I-E scale suggests that rather than being unidimensional, the scale is composed of two factors. The first factor consists of items dealing with the issue of personal control, while the second factor is based on items dealing with the issue of political efficacy. The present study attempted to associate differentially the two factors with criterion variables by using a correlational design and an experimental intervention design. Results from the correlational analysis support he hypothesis that the I-E scale is not homogeneous, while results from the intervention part of the study were equivocal. Difficulties encountered in attempting ro alter a person's locus of control were discussed. In recent years, several investigators have questioned the unidimensionality of Rotter's I-E scale. Although Rotter's original factor analysis of the 1.E scale yielded only one large factor (Rotter, 1966), ocher factor analyses have not confirmed this finding. One extensive factor analysis performed on data collected from black college students yielded four dimensions of internal-external control (Gurin, Gurin, Lao, & Beattie, 1969). A more recent study (Mirels, 1970) yielded two factors of internal-external control. The first factor was composed of items worded in the first person and dealing wich the issue of personal control of one's destiny versus fate. The second factor was composed of items worded in an impersonal frame of reference and focusing on the issue of political efficacy. At the conclusion of his study, Mirels stated that more convincing evidence that the I-E scale is composed of two distinct factors would "entail a demonstration of their differential association wich relevant criterion variables" (1970). A search of the literature shows that only one author (Abramowitz, 1973) has reported such a differential association of Mirels' two factors with a criterion. Although Abramowitz's correlational data raise a serious doubt about the homogeneicy of the I-E scale, even more compelling evidence might be provided if the two Mirels factors could be differentially manipulated, chat is, if subjects could be given some treatment which would change the score they receive on one factor and not on the other. The present study was designed to provide both correlational and controlled experimental tests of Mirels' hypothesis. Following the Gorman (1968) and McArthur (1970) studies, the authors assumed that subjects would become more external when chey feel they cannot control the outcome of situations in which chey have a high personal stake. Specifically, in an achievement-oriented popu
Tracking @stemxcomet: teaching programming to blind students via 3D printing, crisis management, and twitter

Introductory programming activities for students often include graphical user interfaces or other visual media that are inaccessible to students with visual impairments. Digital fabrication techniques such as 3D printing offer an opportunity for students to write programs that produce tactile objects, providing an accessible way of exploring program output. This paper describes the planning and execution of a four-day computer science education workshop in which blind and visually impaired students wrote Ruby programs to analyze data from Twitter regarding a fictional ecological crisis. Students then wrote code to produce accessible tactile visualizations of that data. This paper describes outcomes from our workshop and suggests future directions for integrating data analysis and 3D printing into programming instruction for blind students.
Purification of human placental lactogen.

Human placental lactogen (HPL) of high specific activity has been isolated by modification of a previously reported procedure. Precipitation at pH 5 prior to gel filtration consistently removes 36% of protein with minimal loss of HPL activity. Activity by immunoassay and the production of lipolysis from isolated fat cells shows the material to be more potent than HPL prepared by previously described methods. (Endocrinology 79:187,1966)
Electric orbit transfer vehicle cryogenic propellant system

Abstract An electric orbit transfer vehicle (EOTV) is intended to transfer payloads from low Earth orbit (LEO) to higher orbits using low-thrust solar-electric propulsion and hydrogen propellant. Because of its high specific impulse and synergistic sharing of power supply, attitude control and communication systems with the payload, the highly efficient EOTV transfer stage permits use of a smaller, less costly launch vehicle than if orbit transfer were accomplished using chemical propulsion. Study of the propellant storage and supply system for an EOTV intended to fly a 168 day spiral trajectory from LEO to geosynchronous orbit (GEO) reveals that the low propellant flow rate needed by the thrusters can be supplied by the boil-off from the storage tank, eliminating the need for any overboard venting. The tank can be fabricated under the same pressure-stabilized, thin, stainless steel monocoque construction as the current Centaur upper stage, and insulated with Centaur fixed foam and MLI. The tank contains a thermodynamic vent system (TVS) for control of tank pressure in zero and low gravity and for supply of propellant to the thrusters. An external compressor, accumulator and regulator condition the hydrogen boil-off provided by the TVS and provide for start-up and shut-down transients. The resulting system is simple, has a very low structural mass fraction and builds on the Centaur cryogenic upper stage technology, which has been operational for over 25 years.
Gender differences in speech temporal patterns detected using lagged co-occurrence text-analysis of personal narratives.

This paper describes a novel methodology for the detection of speech patterns. Lagged co-occurrence analysis (LCA) utilizes the likelihood that a target word will be uttered in a certain position after a trigger word. Using this methodology, it is possible to uncover a statistically significant repetitive temporal patterns of word use, compared to a random choice of words. To demonstrate this new tool on autobiographical narratives, 200 subjects related each a 5-min story, and these stories were transcribed and subjected to LCA, using software written by the author. This study focuses on establishing the usefulness of LCA in psychological research by examining its associations with gender. The application of LCA to the corpus of personal narratives revealed significant differences in the temporal patterns of using the word “I” between male and female speakers. This finding is particularly demonstrative of the potential for studying speech temporal patterns using LCA, as men and women tend to utter the pronoun “I” in comparable frequencies. Specifically, LCA of the personal narratives showed that, on average, men tended to have shorter interval between their use of the pronoun, while women speak longer between two subsequent utterances of the pronoun. The results of this study are discussed in light of psycholinguistic factors governing male and female speech communities.
Frequency-modulation–polarization spectroscopy

We have combined frequency-modulation and polarization spectroscopy to detect anisotropic spectral features with high sensitivity. The many line shapes possible with this technique and the potential for laser noise suppression were demonstrated by using saturation holes in iodine vapor.
Performance Analysis of Noncoherent Pulse Compression Technique

Noncoherent pulse compression (NCPC) is a recently investigated variant of the classical (coherent) coded pulse compression technique [1-5]. The performance of NCPC under various signal-to-noise ratio (SNR) conditions is investigated and compared with coherent pulse compression (CPC). Various performance measurement approaches are used to quantify NCPC performance. All of them indicate very similar performance trends. It was found that, as the SNR of received signal decreases, the advantage of pulse compression in terms of improved SNR, gets diminished. It is therefore argued that NCPC is not well suited for low input SNR conditions, and for applications requiring large pulse compression gain.
Microwave noise characterization of GaAs MESFET's: determination of extrinsic noise parameters

A previously proposed noise equivalent circuit model for a GaAs MESFET (M. S. Gupta et al., ibid., vol.35, no.12, p.1208-18, 1987) is supplemented with a model for device parasitics, in order to calculate the noise parameters of a mounted GaAs MESFET. The calculated parameters are in good agreement with measured noise parameters from 2 to 18 GHz. The model is thus established as a valid representation of the noise properties of the device. The model is useful in that, compared with the measured and tabulated noise parameters, its elements are easier to obtain, and it serves as a simpler, more compact description of the noise characteristics of the MESFET. >
Morphology and kinetics of crystallization of amorphous V75Si25 thin-alloy films

Electrical and microstructural changes of coevaporated V75Si25 alloy thin films have been studied as a function of temperature from room temperature to 830 °C. In situ resistivity measurements, hot‐stage transmission electron microscopy, Rutherford backscattering spectroscopy and the Seeman–Bohlin glancing angle incidence x‐ray diffraction technique were applied. Upon heat treatment at a heating rate of 8 °C/min, a sharp decrease in resistivity occurs at ∼670 °C which results from an amorphous to crystalline phase transformation. The crystallized phase was identified as V3Si. The mechanism of transformation is random nucleation at a rapidly decreasing rate and a fast quasi‐isotropic growth. The kinetics of crystallization have been studied by utilizing electrical resistivity measurements during isothermal heat treatment. Six different temperatures between 570 °C and 630 °C were adopted. The apparent activation energy (∼3.6 eV) obtained from isothermal measurements was found to be in agreement with that ob...
Human platelet myosin. I. Purification by a rapid method applicable to other nonmuscle cells

Abstract Using refinements of established procedures and a new two buffer gel filtration method, it is possible to prepare human platelet myosin which by gel electrophoresis is free from actin and over 95% pure. This method with minor modifications is useful for the purification of myosin from several other nonmuscle cells.
Comparative studies of the infection of Lewis rats with four Trypanosoma cruzi clones.

Quantitative and qualitative differences in parasitaemia levels and histopathological characteristics occurred in Lewis rats infected with four Trypanosoma cruzi clones. Rats infected with clone Sylvio-X10/7 sustained high parasitaemias and died during the acute phase whereas rats infected with clones Sylyio-X10/4, Miranda/78 or Miranda/80 did not. Myocardial fibrosis was more extensive in rats chronically infected with clone X10/4 than in rats infected with the 2 Miranda clones. Myocardial fibrosis developed more rapidly in rats than has been reported in mice. These characteristics are advantageous in developing animal models of human chagasic myocardiopathy.
Nitric oxide mediates the formation of synaptic connections in developing and regenerating olfactory receptor neurons

Nitric oxide (NO) is a diffusible free radical that functions as a second messenger and neurotransmitter. NO synthase (NOS) is highly and transiently expressed in neurons of the developing olfactory epithelium during migration and establishment of primary synapses in the olfactory bulb. NOS is first expressed at E11 in cells of the presumptive nervous layer of the olfactory placode. NOS immunoreactivity persists in the descendants of these cells that differentiate into embryonic olfactory receptor neurons (ORNs). Olfactory NOS expression in the ORN and in its afferents rapidly declines after birth and is undetectable by P7. Following bulbectomy, NOS expression is rapidly induced in the regenerating ORN and is particularly enriched in their outgrowing axons. Immunoblot and Northern blot analyses similarly demonstrate an induction of NOS protein and mRNA expression, respectively, the highest levels of which coincide with peaks of ORN regeneration. These data argue against a role for NO in odorant-sensitive signal transduction, but suggest a prominent function for NO in activity-dependent establishment of connections in both developing and regenerating olfactory neurons.
Circadian rhythm of nuclear DNA in adult rat liver

Abstract Nuclei were isolated from adult rat livers at 2 h intervals over a 24 h period. The average DNA content per nucleus was determined in each nuclear suspension. It was found that there is a significant variation in the DNA content. The high point occurred during the late afternoon while the minimum was noted during the early morning. There also is a sharp peak of incorporation of 3H-thymidine between 0200 and 0400 hours. It is assumed that much of this incorporation cannot be counted for by mitosis since the mitotic index was found to be very low (0.03–0.05%). Possible mechanisms which could account for these observed cyclic variations are discussed.
Intracanalicular arachnoid cyst mimicking acoustic neuroma: CT and MRI.

Abstract A patient with a surgically proven intracanalicular archnoid cyst was studied using computed tomography, magnetic resonance imaging, and air CT cisternography. The lesion had a similar radiographic appearance to acoustic neuroma and therefore, although rare, must be considered in the differential diagnosis of intracanalicular mass lesions. We report a case in which examination was performed, in evaluating the lesion, utilizing high-resolution air CT cisternography and magnetic resonance imaging (MRI).