cssi/SciSciGPT-SciSciNet huggingface dataset:
Nuclear Deterrence Theory: The Search for Credibility

Applying advances in game theory to the study of nuclear deterrence, Robert Powell examines the foundations of deterrence theory. Game-theoretic analysis allows the author to explore some of the most complex and problematic issues in deterrence theory, including the effects of first-strike advantages, limited retaliation, and the number of nuclear powers in the international system on the dynamics of escalation. With the formalizations he develops, the author is able to demonstrate the fundamental similarity of the two seemingly disparate deterrrent strategies that have evolved in response to the nuclear revolution and the condition of mutually assured destruction: the strategy of limited retaliation. The author argues that the logic underlying both strategies centres on a search for ways to make the use of force or the threat of its use credible when any use of force might escalate to mutual devastation.
Torus quantization of symmetrically excited helium.

The recent discovery by Richter and Wintgen [J. Phys. B 23, L197 (1990)] that the classical helium atom is not globally ergodic has stimulated renewed interest in its semiclassical quantization. The Einstein-Brillouin-Keller quantization of Kolmogorov-Arnold-Moser tori around stable periodic orbits becomes locally possible in a selected region of phase space. Using a hyperspherical representation we have found a dynamically confining potential allowing for a stable motion near the Wannier ridge. The resulting semiclassical eigenenergies provide a test for full quantum calculations in the limit of very high quantum numbers. The relations to frequently used group-theoretical classifications for doubly excited states and to the periodic-orbit quantization of the chaotic portion of the phase space are discussed. The extrapolation of the semiclassical quantization to low-lying states give remarkably accurate estimates for the energies of all symmetric L=0 states of helium.
Effects of PNU-109,291, a selective 5-HT1D receptor agonist, on electrically induced dural plasma extravasation and capsaicin-evoked c-fos immunoreactivity within trigeminal nucleus caudalis.

Abstract We studied the effects of PNU-109 291 [(S)-(−)-1-[2-[4-(4-methoxyphenyl)-1-piperazinyl]ethyl]-N-methyl-isochroman-6-carboxamide], a receptor agonist showing 5000-fold selectivity for primate 5-HT1D versus 5-HT1B receptors (Ennis et al., J. Med. Chem. 41, 2180–2183), on dural neurogenic inflammation and on c-fos like immunoreactivity within trigeminal nucleus caudalis evoked by electrical and chemical activation of trigeminal afferents, respectively. Subcutaneous injection of PNU-109 291 in male guinea pigs dose-dependently reduced dural extravasation of [125I]-labeled bovine serum albumin evoked by trigeminal ganglion stimulation with an IC50 of 4.2 nmol kg−1. A dose of 73.3 nmol kg−1 blocked the response completely. The selective 5-HT1B/1D receptor antagonist GR-127 935 (≥2 μmol kg−1 i.v.) prevented this effect. In addition, the number of c-fos immunoreactive cells within guinea pig trigeminal nucleus caudalis induced by chemical meningeal stimulation (intracisternally administered capsaicin) was reduced by more than 50% with PNU-109 291 (≥122.2 nmol kg−1 administered s.c. 45 min before and 15 min after capsaicin). These data indicate that the 5-HT1D receptor subtype plays a significant role in suppressing meningeal neurogenic inflammation and attenuating trigeminal nociception in these guinea pig models. Since 5-HT1D receptor mRNA and protein are expressed in trigeminal ganglia but not vascular smooth muscle, the 5-HT1D receptor subtype may become a useful therapeutic target for migraine and related headaches.
Strained Si films grown by chemical vapor deposition of trisilane on Ge buffered Si(100)

Abstract Relaxed Ge buffer layers were grown on Si substrates using a recently developed chemical vapor deposition (CVD) approach that combines digermylmethane and digermane precursors. Ultrathin Si films were deposited on these buffer layers at 420 °C by CVD using trisilane as a precursor. The Si films were studied with a variety of experimental techniques, with emphasis on Raman spectroscopy. The analysis of the Raman results shows that a thin (
On the role of magnesium ions in RNA stability

Divalent cations, like magnesium, are crucial for the structural integrity and biological activity of RNA. In this article, we present a picture of how magnesium stabilizes a particular folded form of RNA. The overall stabilization of RNA by Mg2+ is given by the free energy of transferring RNA from a reference univalent salt solution to a mixed salt solution. This term has favorable energetic contributions from two distinct modes of binding: diffuse binding and site binding. In diffuse binding, fully hydrated Mg ions interact with the RNA via nonspecific long-range electrostatic interactions. In site binding, dehydrated Mg2+ interacts with anionic ligands specifically arranged by the RNA fold to act as coordinating ligands for the metal ion. Each of these modes has a strong coulombic contribution to binding; however, site binding is also characterized by substantial changes in ion solvation and other nonelectrostatic contributions. We will show how these energetic differences can be exploited to experimentally distinguish between these two classes of ions using analyses of binding polynomials. We survey a number of specific systems in which Mg2+–RNA interactions have been studied. In well-characterized systems such as certain tRNAs and some rRNA fragments these studies show that site-bound ions can play an important role in RNA stability. However, the crucial role of diffusely bound ions is also evident. We emphasize that diffuse binding can only be described rigorously by a model that accounts for long-range electrostatic forces. To fully understand the role of magnesium ions in RNA stability, theoretical models describing electrostatic forces in systems with complicated structures must be developed. © 1999 John Wiley & Sons, Inc. Biopoly 48: 113–135, 1998
The motions of satellites

THE MOTIONS OF SATELLITES are well understood in that the basic fundamentals on which the motions are based go back before the invention of the telescope. Today, the scientists can describe the motions of the satellites with great accuracy.
High frequency resonant techniques for studying the complex electrodynamic response in solids

Abstract An overview is given on resonant cavity techniques utilized to study the electrodynamical properties of solids in the microwave and millimeter wave spectral range. The method combines three major advantages over other techniques: it is best developed for frequencies from 3 to 300 GHz, a spectral range hardly accessible by any other method; as a resonant technique it reaches a high sensitivity; and finally it allows for measuring both components of the complex response. Various configurations of microwave and millimeter wave cavities are presented and the advantages of different designs are discussed. A number of examples are presented in which the resonant cavity technique was successfully employed to investigate low energy excitations of solids.
Comment on digestibility of food allergens and nonallergenic proteins in simulated gastric fluid and simulated intestinal fluid--a comparative study.

Information on the comparative digestibility of food allergens and nonallergenic proteins is crucial when stability to digestion is to be used as a criterion to assess the allergenic potential of novel proteins. In this work, we compared the digestive stability of a number of food allergens and proteins of unproven allergenicity and examined whether allergens possess a higher stability than nonallergenic proteins of similar cellular functions, and whether there is a correlation between protein digestibility and allergenicity. The stability of groups of storage proteins, plant lectins, contractile proteins, and enzymes, both allergens and proteins with unproven allergenicity, in a standard simulated gastric fluid and a standard simulated intestinal fluid was measured. Food allergens were not necessarily more resistant to digestion than nonallergenic proteins. There was not a clear relationship between digestibility measured in vitro and protein allergenicity.
Pancreatic islet allograft prolongation by donor-specific blood transfusions treated with ultraviolet irradiation

Survival of allografts of islets of Langerhans in nonimmunosuppressed adult rats was prolonged by transfusions of donor blood irradiated with ultraviolet light before transplantation across a major histocompatibility barrier. This treatment is donor blood-specific and has produced greater than 160-day survival of transplanted islets without the administration of immunosuppressive agents.
Isotopic transient kinetic analysis of ethane hydrogenolysis on Ru/SiO2

Steady-state isotropic transient kinetics analysis has been applied to determine attributes of the active intermediates and the surface kinetics of ethane hydrogenolysis, known to be a very structure-sensitive reaction, on Ru/SiO2. The abundances, coverages, and lifetimes of surface intermediates of the reaction were measured under reaction conditions and their dependence upon temperature was determined. The results show that intrinsic activities and abundances of surface di-carbon and mono-carbon species change in different ways with temperature. The surface coverage of di-carbon species is much lower than that of mono-carbon species, while the reactivity of the mono-carbon species is greater than that of the di-carbon species. The surface coverage of di-carbon species was not found to change with temperature under the conditions studied, while that of mono carbon species increased with increasing temperature. The results suggest that the breakage of the C-C bond is the slowest step for ethane hydrogenolysis. The activation energies of the surface reactions of di- and mono-carbon species were found to be 36 ± 3 and 9 ± 3 kcal/mole, respectively. The exchange reaction of ethane with deuterium was also investigated in order to understand better the reaction mechanism.
The value of standardized exercise testing in the noninvasive evaluation of mitral stenosis.

Abstract The determination of functional impairment is an important portion of the evaluation of patients with mitral stenosis and frequently is instrumental in the determination to proceed with invasive testing. To test the hypothesis that patients with slowly evolving disability from mitral stenosis frequently do not recognize the degree of their limitations and to determine the utility of formal exercise testing, 24 consecutive patients with pure or predominant mitral stenosis were evaluated for NYHA functional category (NYHA class) by historical determination of functional impairment, echocardiographic mitral valve area (echo MVA), exercise duration, estimated maximum oxygen consumption, and functional aerobic impairment during a symptom-limited Bruce protocol exercise test and multiple catheterizationderived parameters. The data revealed no difference in exercise duration or mitral valve area between NYHA classes, but demonstrated an excellent correlation between exercise duration and severity of mitral valve stenosis determined at cardiac catheterization (cath MVA). This relationship was similar to that of echo MVA to cath MVA and exceeded that of exercise time to any other parameter measured during catheterization. Estimation of maximum oxygen consumption or f1.inctional aerobic impairment did not improve the exercise duration to valve area relationship. The data presented thus demonstrate that Bruce protocol exercise testing is a valuable adjunct to other noninvasive tests in the initial evaluation of selected patients with mitral stenosis. By virtue of being easily repeated at low risk, exercise testing may also be useful in long term follow-up of medically treated mitral stenosis patients.
Maternal anthropometric measurements in relation to infant measurements

Abstract Data were collected from 146 women/infant pairs onseveral maternal and infant factors. Triceps skinfolds were measured on 102 mother/infant pairs. Approximately 20% of the women did not gain the amount of weight generally recommended; 55% gained more than the general recommendation. The birth weights of the infants were close to NCHS values. Birth weights tended to increase as an interaction of maternal prepregnancy weight and weight gain during pregnancy. Infant triceps skinfold measurements were not significantly correlated to maternal triceps skinfold measurements but were significantly correlated to infant birth weight, length, head circumference and various weight to length indices (p=0.0001 for all). Women with the largest skinfolds were heavier before pregnancy (p 0.001) and gained more during pregnancy (p 0.01). The greater than recommended weight gain of the women apparently was favorable in the short term, but long term effects on both mothers and their infants in terms of increased tendency toward obesity are not known.
Angular Distributions in Fission Induced by Alpha Particles, Deuterons, and Protons

Protons of 11 Mev, deuterons of energies up to 22 Mev, and alpha particles of energies up to 43 Mev were used to study fission fragment angular distributions in the following targets: ${\mathrm{Bi}}^{209}$, ${\mathrm{Ra}}^{226}$, ${\mathrm{Th}}^{232}$, ${\mathrm{U}}^{238}$, ${\mathrm{U}}^{235}$, ${\mathrm{Np}}^{237}$, and ${\mathrm{Pu}}^{239}$. All of the measured distributions were qualitatively similar in that more fragments were emitted forward and backward along the beam direction than sideways. The largest ratios of 0\ifmmode^\circ\else\textdegree\fi{} to 90\ifmmode^\circ\else\textdegree\fi{} differential cross sections were slightly greater than 2 and were obtained in the alpha-particle bombardments. The smallest ratios occurred in the proton bombardments. If one decomposes the fissions observed at a given bombarding energy into symmetric and asymmetric mass components, the anisotropy for each component decreases smoothly as the value of $\frac{{Z}^{2}}{A}$ of the compound nucleus increases. The asymmetric anisotropies are larger than the symmetric ones. There is no observable effect of the value of the target spin on the observed anisotropies. It is pointed out that some of the observed features of the anisotropies may be accounted for in terms of the fact that some of the fissions occur only after the evaporation of neutrons.
Consent and coercion: research with involuntarily treated persons with mental illness or substance abuse.

Persons can be subject to involuntary treatment for mental illness or substance abuse in a variety of circumstances. The ability of such persons to give a valid informed consent for research often has been called into question, because the coercive nature of the treatment is thought to impair the voluntariness of their decision making. A careful consideration of the nature of coercion from a “moralized”; perspective focuses attention on two elements that determine the acceptability of consent: the fairness of the proposal to which consent is sought, and the moral baseline from which the proposal is made. Even when coercion is not present, disproportionate rewards offered for participation in research can impair the voluntariness of consent, as can the unintended effects of the social structure of the system in which the research is taking place. When coercion, defined as a moralized concept, is not present, however, and other conditions do not substantially impair voluntariness, consent to research legiti...
Calcaneal ultrasound attenuation in older African-American and Caucasian-American women

The lower fracture rates among African-American women relative to Caucasian women may reflect their higher bone mass. However, bone mass is not the only determinant of bone strength: the quality and microarchitecture of the bone are also important. Quantitative ultrasound is believed to measure properties of bone strength that are independent of bone mass. To test the hypothesis that there are racial differences in quantitative ultrasound measures of bone, we recruited 154 African-American women age ⩾65 years. A random sample of 300 Caucasian women participating in the Study of Osteoporotic Fractures in Pittsburgh, Pennsylvania, was chosen for comparison. The Walker Sonix UBA 575+ was used to measure calcaneal broadband ultrasonic attenuation (BUA). Duplicate BUA measurements were obtained with a reproducibility of 5%. We measured bone mineral density (BMD) of the hip and calcaneus using single (calcaneus) or dual (hip) energy X-ray absorptiometry. The correlation between BUA and calcaneal BMD was similar in Caucasians (r=0.66,p<0.001) and African-Americans (r=0.58,p<0.001). Age-adjusted BUA (dB/MHz) was higher among the African-American women than Caucasian women (69.1 and 66.2, respectively), but these differences were not statistically significant, (p=0.12). Adjustment for calcaneal BMD completely attenuated the racial differences in BUA. BMD at the femoral neck and calcaneus was higher among the African-American women, even after adjusting for age, height and weight. In conclusion, our results suggest that racial differences in rates of fracture cannot be explained by differences in bone quality as assessed by ultrasound attenuation.
Upper airway and diaphragmatic muscle activity following acute cocaine administration.

Abstract These studies examined activity of the diaphragm and a laryngeal dilator, the posterior cricoarytenoid, following 3 levels of intravenous and cerebral ventricular administration of cocaine. Both administration routes induced extremely high respiratory rates with enhanced tonic and phasic electromyographic activity, and affected patterning similarly in upper airway and diaphragmantic muscles. Both intravenous and intraventricular administration induced a rise in core and brain temperature related to the route of administration; however, the tachypnea was only loosely related to the hyperthermia. Intraventricular administration resulted in a more rapid onset of peak respiratory rates, and a faster decline than an intravenous route. Different dose levels elicited similar elevated respiratory rates, but higher intravenous doses also resulted in extensive hypertonicity with intemittent phasic movements. Tachypnea continued between these phasic efforts. The phasic events associated with high doses were accompanied by sustained inspiratory efforts; however, no evidence of obstructive apnea was found. These data suggest that cocaine can modify respiratory patterning by inducing a centrally mediated tachypnea and by eliciting sustained, intermittent inspiratory efforts.
Magneto-aerotaxis in Marine Coccoid Bacteria

Magnetotactic cocci swim persistently along local magnetic field lines in a preferred direction that corresponds to downward migration along geomagnetic field lines. Recently, high cell concentrations of magnetotactic cocci have been found in the water columns of chemically stratified, marine and brackish habitats, and not always in the sediments, as would be expected for persistent, downward-migrating bacteria. Here we report that cells of a pure culture of a marine magnetotactic coccus, designated strain MC-1, formed microaerophilic bands in capillary tubes and used aerotaxis to migrate to a preferred oxygen concentration in an oxygen gradient. Cells were able to swim in either direction along the local magnetic field and used magnetotaxis in conjunction with aerotaxis, i.e., magnetically assisted aerotaxis, or magneto-aerotaxis, to more efficiently migrate to and maintain position at their preferred oxygen concentration. Cells of strain MC-1 had a novel, aerotactic sensory mechanism that appeared to function as a two-way switch, rather than the temporal sensory mechanism used by other bacteria, including Magnetospirillum megnetotacticum, in aerotaxis. The cells also exhibited a response to short-wavelength light (
The density minimum at the earth's magnetic equator

Observations of the density structure in the plasmapause region reveal the existence of a local minimum in the total electron density at the magnetic equator. Data from the plasma wave instrument and ion mass spectrometer on the DE-1 satellite are used to study this phenomenon. The density depletion typically extends from +/- 5 to +/- 20 deg in latitude and is found at altitudes from 2 to 5 RE. Density depletions of 10-70 percent are found in regions where the off-equator density ranges from 10 to 1000/cu cm. This density structure is associated with equator crossings where the thermal plasma has been heated over normal plasmasphere values. The heated plasma is the equatorially trapped plasma previously reported from DE 1 and the SCATHA satellite. Within the plasmasphere, the drop in total (electron) density corresponds to a decrease in the cold-ion density, in both H(+) and He(+). There is a rough pressure balance provided by the warm tail of the distribution, which is a few percent by density but 1-2 orders of magnitude higher in temperature.
Coherent Magnetization Rotation and Phase Control by Ultrashort Optical Pulses in CrO 2 Thin Films

We have applied photoexcitation by ultrashort laser pulses to single crystal thin CrO 2 films to trigger coherent transient magnetization rotation on a subnanosecond time scale, in macroscale single domains. Moreover, by applying the photoexcitation by pairs of temporally separated pump pulses, the transient precession of the magnetization can be phase controlled, depending on the time separation between the pulses. The mechanism behind the photoexcitation originates from the modulation of the magnetocrystalline anisotropy by nonthermal hot electron spins.
Mathematics Courses for Elementary Teachers

(1978). Mathematics Courses for Elementary Teachers. The American Mathematical Monthly: Vol. 85, No. 8, pp. 678-680.
Vasodilatory actions of calcitonin gene-related peptide and nitric oxide in parenchymal microvessels of the rat hippocampus

Abstract Calcitonin gene-related peptide (CGRP) and nitric oxide (NO) are potent dilators in a variety of vascular beds. Recent evidence suggests that NO may serve as an intermediary messenger for CGRP and/or CGRP may serve as an intermediary messenger for NO in the expression of vasodilation. The present study was designed to provide an initial characterization of the responses to NO and CGRP in parenchymal microvessels and to determine whether NO and/or CGRP act as intermediaries for one another. Microvessels in the parenchyma of in vitro hippocampal slices from rat brain were examined using computer-assisted videomicroscopy. The resting diameter of the microvessels ranged from 9 to 26 μm. Treatment with the nitric oxide synthase inhibitor, N G -nitro-l-arginine ( l -NNA; 100 μM) constricted vessels to 64.2% ± 3.0% of resting luminal diameter. Sodium nitroprusside (SNP; 1 μM), a donor of NO, reversed the l -NNA-induced vasoconstriction by 77.0% ± 15.0%. CGRP alone (10 nM) elicited a small but significant vasodilatory effect on resting vascular tone (2.3% ± 0.6%). In the presence of l -NNA, CGRP elicited a significant dose-dependent vasodilatory response, and 10 nM CGRP elicited a sizeable response, reversing the l -NNA-induced constriction by 84.3% ± 15.5%. This CGRP-induced dilation was inhibited by pretreatment with the CGRP receptor antagonist, CGRP fragment (8–37) (1 μM). In contrast, pretreatment with 1 μM CGRP fragment (8–37) did not attenuate the SNP-induced dilation in the presence of l -NNA. Taken together, these findings demonstrate that CGRP and NO are potent dilators of parenchymal microvessels, and that NO provides a substantial relaxant effect on resting tone. In addition, the results indicate that CGRP is not a necessary intermediary in NO-induced dilation, and that NO is not a necessary intermediary in CGRP-induced dilation in parenchymal microvessels.
A Role for Thrombopoietin in Hemangioblast Development

Vascular endothelial growth factor (VEGF) and stem cell factor (SCF) act as growth factors for the hemangioblast, an embryonic progenitor of the hematopoietic and endothelial lineages. Because thrombopoietin (TPO) and its receptor, c-Mpl, regulate primitive hematopoietic populations, including bone marrow hematopoietic stem cells, we investigated whether TPO acts on the hemangioblasts that derive from differentiation of embryonic stem cells in vitro. Reverse transcriptase polymerase chain reaction analysis detected expression of c-Mpl beginning on day 3 of embryoid body differentiation when the hemangioblast first arises. In assays of the hemangioblast colony-forming cell (BL-CFC), TPO alone supported BL-CFC formation and nearly doubled the number of BL-CFC when added together with VEGF and SCF. When replated under the appropriate conditions, TPO-stimulated BL-CFC gave rise to secondary hematopoietic colonies, as well as endothelial cells, confirming their nature as hemangioblasts. Addition of a neutralizing anti-VEGF antibody did not block TPO enhancement of BL-CFC formation, suggesting that TPO acts independently of VEGF. These results establish that Mpl signaling plays a role in the earliest stages of hematopoietic development and that TPO represents a third growth factor influencing hemangioblast formation.
Relativistic mean field plus exact pairing approach to open shell nuclei

Background: Pairing correlations play a critical role in determining numerous properties of open shell nuclei. Traditionally, they are included in a mean field description of atomic nuclei through the approximate Bardeen-Cooper-Schrieffer or Hartree-Fock-Bogoliubov formalism.Purpose: We propose a new hybrid ``relativistic mean field plus pairing'' approach in which pairing is treated exactly so the number of particles is conserved. To verify the reliability of the formalism, we apply it to the study of both ground-state properties and isoscalar monopole excitations of the tin isotopes.Methods: Accurately calibrated relativistic mean field models supplemented by an exact treatment of pairing correlations are used to compute ground-state observables along the isotopic chain in tin. In turn, ground-state densities are used as input to the calculation of giant monopole resonances through a constrained-relativistic approach.Results: We compute a variety of ground-state observables sensitive to pairing correlations as well as the evolution of giant monopole energies along the isotopic chain in tin. Whereas ground-state properties are consistent with experiment, we find that pairing correlations have a minor effect on the giant monopole energies.Conclusions: A new mean field plus pairing approach is introduced to compute properties of open shell nuclei. The formalism provides an efficient and powerful alternative to the computation of both ground-state properties and monopole energies of open shell nuclei. We find ground-state properties to be well reproduced in this approach. However, as many have concluded before us, we find that pairing correlations are unlikely to provide an answer to the question, ``Why is tin so soft?''
Essential role of G protein-gated inwardly rectifying potassium channels in gonadotropin-induced regulation of GnRH neuronal firing and pulsatile neurosecretion.

Activation of the luteinizing hormone/human chorionic gonadotropin (LH/hCG) receptor (LHR) in cultured hypothalamic cells and immortalized GnRH (gonadotropin-releasing hormone) neurons (GT1–7 cells) transiently stimulates and subsequently inhibits cAMP production and pulsatile GnRH release. The marked and delayed impairment of cAMP signaling and episodic GnRH release in GT1–7 cells is prevented by pertussis toxin (PTX). This, and the LH-induced release of membrane-bound Gαs and Gαi3 subunits, are indicative of differential G protein coupling to the LHR. Action potential (AP) firing in identified GnRH neurons also initially increased and then progressively decreased during LH treatment. The inhibitory action of LH on AP firing was also prevented by PTX. Reverse transcriptase-PCR analysis of GT1–7 neurons revealed the expression of G protein-gated inwardly rectifying potassium (GIRK) channels in these cells. The LH-induced currents were inhibited by PTX and were identified as GIRK currents. These responses indicate that agonist stimulation of endogenous LHR expressed in GnRH neurons activates GIRK channels, leading to suppression of membrane excitability and inhibition of AP firing. These findings demonstrate that regulation of GIRK channel function is a dominant factor in gonadotropin-induced abolition of pulsatile GnRH release. Furthermore, this mechanism could contribute to the suppression of pituitary function during pregnancy.
An evaluation of nebulized prostacyclin in patients with primary and secondary pulmonary hypertension

Aims To investigate the response to inhaled prostacyclin in patients with primary and secondary pulmonary hypertension and to compare its effects to those of intravenous prostacyclin and inhaled nitric oxide. Methods and results Twelve patients with pulmonary hypertension (seven primary and five secondary) were studied. All patients had a pulmonary artery balloon flotation catheter inserted into the proximal pulmonary artery and radial arterial line. Prostacyclin was nebulized with 81. min−1 of oxygen and administered in doses increasing from 15 to 50 ng. kg−1. min−1 via a facemask. Eight of these patients also received intravenous prostacyclin in doses of 1 to 5 ng.kg−1.min−1 and nitric oxide in doses of 10 to 100 ppm via a facemask. Haemodynamic measurements were taken during each treatment. In the 12 patients, nebulized prostacyclin produced a significant reduction in mean pulmonary artery pressure from 56±5 to 45±4 mmHg ( P =0·0001). The pulmonary vascular resistance decreased by 38% from 964±169 to 595±116 dyne s−1.cm−5 ( P =0·0001). Direct comparison with inhaled nitric oxide and intravenous prostacyclin in eight patients demonstrated that nebulized prostacyclin produced a greater fall in mean pulmonary artery pressure than the other two agents without any significant effect on systemic arterial pressure. Conclusion Nebulized prostacyclin appears to be more effective at reducing pulmonary artery pressure in patients with pulmonary hypertension when compared to intravenous prostacyclin and inhaled nitric oxide. This could have important clinical implications for the management of patients with pulmonary hypertension.
Comparative effects of 5,6-dihydroxytryptamine and its benzo[b]-thiophene analogue on biogenic amines in the rat.

Abstract The effects of 5,6-dihydroxytryptamine (5,6-DHT) and its benzo[ b ]thiophene analogue (5,6-DHT-S) have been compared with regard to their ability to influence tissue levels of serotonin (5-HT) and norepinephrine (NE) in rats. After i.p. administration, both compounds caused significant reduction in NE levels in heart and spleen, while only 5,6-DHT reduced spleen 5-HT, and neither compound had any effect on brain NE or 5-HT. When administered directly into the lateral ventricle, both compounds caused reduced NE levels: the duration of effect was less than 1 day. In contrast to the prolonged lowering of brain 5-HT and 5-hydroxyindo leacetic acid (5-HIAA) observed after 5,6-DHT, the benzo[ b ]thiophene analogue was without effect.
Analysis of bacterial migration: II. Studies with multiple attractant gradients

Many motile bacteria exhibit chemotaxis, the ability to bias their random motion toward or away from increasing concentrations of chemical substances which benefit or inhibit their survival, respectively. Since bacteria encounter numerous chemical concentration gradients simultaneously in natural surroundings, it is necessary to know quantitatively how a bacterial population responds in the presence of more than one chemical stimulus to develop predictive mathematical models describing bacterial migration in natural systems. This work evaluates three hypothetical models describing the integration of chemical signals from multiple stimuli: high sensitivity, maximum signal, and simple additivity. An expression for the tumbling probability for individual stimuli is modified according to the proposed models and incorporated into the cell balance equation for a 1-D attractant gradient. Random motility and chemotactic sensitivity coefficients, required input parameters for the model, are measured for single stimulus responses. Theoretical predictions with the three signal integration models are compared to the net chemotactic response of Escherichia coli to co- and antidirectional gradients of D-fucose and [alpha]-methylaspartate in the stopped-flow diffusion chamber assay. Results eliminate the high-sensitivity model and favor the simple additivity over the maximum signal. None of the simple models, however, accurately predict the observed behavior, suggesting a more complexmore » model with more steps in the signal processing mechanism is required to predict responses to multiple stimuli.« less
Role of protein kinase C in TBT-induced inhibition of lytic function and MAPK activation in human natural killer cells.

Human natural killer (NK) cells are lymphocytes that destroy tumor and virally infected cells. Previous studies have shown that exposure of NK cells to tributyltin (TBT) greatly diminishes their ability to destroy tumor cells (lytic function) while activating mitogen-activated protein kinases (MAPK) (p44/42, p38, and JNK) in NK cells. The signaling pathway that regulates NK lytic function appears to include activation of protein kinase C (PKC) as well as MAPK activity. TBT-induced activation of MAPKs would trigger a portion of the NK lytic signaling pathway, which would then leave the NK cell unable to trigger this pathway in response to a subsequent encounter with a target cell. In the present study we evaluated the involvement of PKC in inhibition of NK lysis of tumor cells and activation of MAPKs caused by TBT exposure. TBT caused a 2–3-fold activation of PKC at concentrations ranging from 50 to 300 nM (16–98 ng/ml), indicating that activation of PKC occurs in response to TBT exposure. This would then leave the NK cell unable to respond to targets. Treatment with the PKC inhibitor, bisindolylmaleimide I, caused an 85% decrease in the ability of NK cells to lyse tumor cells, validating the involvement of PKC in the lytic signaling pathway. The role of PKC in the activation of MAPKs by TBT was also investigated using bisindolylmaleimide I. The results indicated that, in NK cells where PKC activation was blocked, there was no activation of the MAPK, p44/42 in response to TBT. However, TBT-induced activation of the MAPKs, p38 and JNK did not require PKC activation. These results indicate the pivotal role of PKC in the TBT-induced loss of NK lytic function including activation of p44/42 by TBT in NK cells.
A comparative study of fuels for on-board hydrogen production for fuel-cell-powered automobiles

Abstract Seven common fuels are compared for their utility as hydrogen sources for proton-exchange-membrane fuel cells used in automotive propulsion. Methanol, natural gas, gasoline, diesel fuel, aviation jet fuel, ethanol, and hydrogen are the fuels considered. Except for steam-reforming methanol and using pure hydrogen, all processes for generating hydrogen from these fuels require water–gas shift reactors of significant size. This occurs because their higher processing temperatures produce unacceptably large amounts of CO. All processes require low- or zero-sulfur fuels, and this may add cost to some of them. Fuels produced by pure steam-reforming contain ∼70–80% hydrogen, those by pure partial oxidation ∼35–45%. The lower percentages may adversely affect cell performance. Pure steam-reforming suffers from poor transient operation. Theoretical input energies do not differ markedly among the processes for generating hydrogen from organic-chemical fuels. Pure hydrogen has formidable distribution and storage difficulties. The factors considered in this work make some combination of partial oxidation and steam-reforming of methanol technically the leading candidate for on-board generation of hydrogen for automotive propulsion. The possible use of methanol suffers from a lack of infrastructure and solubility in water combined with toxicity. Methanol's disadvantages have stimulated extensive current research employing other primary fuels for this purpose.
Human tracking using a two-element antenna array

We investigate the use of a low-cost, two-element receiving array for tracking human movements in indoor surveillance applications. Conventional direction of arrival (DOA) detection requires the use of an antenna array with multiple elements. Here we investigate the use of only two elements in the receiver array. The concept entails simultaneously resolving the Doppler frequencies of the returned signals from the moving targets and the DOA of the targets. Simulation is performed to demonstrate the concept. Both the monostatic and the bistatic scenario where the transmitter and the receiving array are placed at different locations are investigated. DOA errors and tolerances are analyzed for each scenario. An experimental system is constructed to test the concept. The system consists of a two-element receiver array operating at 2.4 GHz. Measurement results of various collection scenarios are presented.
Auxiliary strategies for the preparation of β-amino alcohols with reductive cross-coupling and a synthesis of (−)-cytoxazone

Abstract Imine auxiliaries including chiral N-tert-butanesulfinyl imines have been successfully utilized to provide stereochemical control to the reductive cross-coupling of imines with aldehydes or ketones. This methodology has been applied to the synthesis of (−)-cytoxazone.
Threshold selection based on fuzzy c-partition entropy approach

Abstract Thresholding is an important topic for image processing, pattern recognition and computer vision. Selecting thresholds is a critical issue for many applications. The fuzzy set theory has been successfully applied to many areas, such as control, image processing, pattern recognition, computer vision, medicine, social science, etc. It is generally believed that image processing bears some fuzziness in nature. In this paper, we use the concept of fuzzy c -partition and the maximum fuzzy entropy principle to select threshold values for gray-level images. We have conducted experiments on many images. The experimental results demonstrate that the proposed approach can select the thresholds automatically and effectively, and the resulting images can preserve the main features of the components of the original images very well.
Very Long-term Outcomes of PAF/CAF Ablation

Ablative intervention for atrial fibrillation may be highly successful in decreasing the frequency of episodes and improving quality of life. Nevertheless the majority of studies used to support ablative therapy track outcomes for no more than one year. In six clinical trials, success rates as high as 70–80% have been reported. In the STOP AF trial, 69.9% of patients were AF free following cryo balloon ablation compared with 7.3% of patients commonly treated with antiarrhythmic drug therapy. In other clinical trials, the success rate for drug therapy has been in the 10–30% range. The Second International Ablation Registry has suggested longer-term success rates of 75% for patients with paroxysmal atrial fibrillation and 65% in those with more long-standing persistent atrial fibrillation.More recently, several groups have reported their long-term results, chronicling outcomes over the course of 3–5 years. Wokhlu, et al., reported the 3-year outcomes in patients undergoing ablative intervention. This was closer to 60–65% in those with paroxysmal atrial fibrillation and 55–65% in those with long standing persistent atrial fibrillation. Predictors of recurrence included the use of WACA ablation, along with the presence of significant underlying disease, long standing persistent atrial fibrillation, and factors such as hypertension and diabetes, suggesting a substrate mediated potential for recurrence. Others including Feld, Steinberg, Haissaguerre, and Kuck have identified similar outcomes.As such, the long-term success rates may be appreciably different than those indicated on web sites and in observational studies. Another limitation of these data is that they chronicle short-term efficacy, without looking at long-term efficacy and safety outcomes. In the CABANA Trial, 3000 patients will be enrolled and followed for 3–5 years to establish the utility of ablation in decreasing mortality related to atrial fibrillation. In addition, long-term stroke, pulmonary vein stenosis, and neurologic outcomes will be tracked. This study is well under way, having already enrolled 400 patients, with plans to complete enrollment within 2 additional years. This international study will be critically important to give the very best sense of long-term outcomes of ablation. This presentation in Japan will chronicle available data and look into the future as to the anticipated outcomes of this nonpharmacologic approach.
Architecture-Aware Mapping and Optimization on a 1600-Core GPU

The graphics processing unit (GPU) continues to make in-roads as a computational accelerator for high-performance computing (HPC). However, despite its increasing popularity, mapping and optimizing GPU code remains a difficult task, it is a multi-dimensional problem that requires deep technical knowledge of GPU architecture. Although substantial literature exists on how to map and optimize GPU performance on the more mature NVIDIA CUDA architecture, the converse is true for OpenCL on an AMD GPU, such as the 1600-core AMD Radeon HD 5870 GPU. Consequently, we present and evaluate architecture-aware mapping and optimizations for the AMD GPU. The most prominent of which include (i) explicit use of registers, (ii) use of vector types, (iii) removal of branches, and (iv) use of image memory for global data. We demonstrate the efficacy of our AMD GPU mapping and optimizations by applying each in isolation as well as in concert to a large-scale, molecular modeling application called GEM. Via these AMD-specific GPU optimizations, our optimized OpenCL implementation on an AMD Radeon HD 5870 delivers more than a four-fold improvement in performance over the basic OpenCL implementation. In addition, it outperforms our optimized CUDA version on an NVIDIA GTX280 by 12%. Overall, we achieve a speedup of 371-fold over a serial but hand-tuned SSE version of our molecular modeling application, and in turn, a 46-fold speedup over an ideal scaling on an 8-core CPU.
Thermal Measurements in Rectangular Microchannels

This paper reports on an experimental study of heat transfer in high aspect ratio (width/depth), rectangular micro-channels. A single channel with width of 10 μm was cut into polycarbonate spacers of various thicknesses, resulting in channel depths of 128 μm, 263 μm and 521 μm. Heat transfer experiments were performed with a constant heat flux boundary condition applied at the surface of the channel. Experiments conducted for refrigerant R-124 working fluid in the range Re = 300 − 900 and Pr = 3.6 − 3.8 showed small or no departure from macro-scale predictions for channels with hydraulic diameters larger than 500 μm. Results for the 80:1 aspect ratio channel showed a significant departure from theoretical predictions. Experimental values of local Nusselt numbers were approximately 25 percent lower than predicted using macro-scale theory.Copyright © 2002 by ASME
Beyond Competition: Institutional Isomorphism in U.S. Accounting Research

We propose remedies to the dramatic reduction in the diversity of research topics within the academic accounting literature. As a basis for our recommendations, we apply institutional theory in the field of academic accounting research and propose that responses to identifiable institutional influences rather than competitive forces account for the current exclusion of nonfinancial accounting topics. All three processes of institutional isomorphism (mimetic, coercive, and normative) appear to shape the organizational field of accounting research. However, the field has reached a stage where it is primarily, but not exclusively, motivated by the normative isomorphism. As such, institutional pressures often eclipse theoretical relevance, individual research preferences, and practical applicability. These effects pervade aspects of the accounting academy beyond publishing. We outline programs and propose actions for enhancing diversity as prescriptions for countering the institutional forces acting within th...
Extending intervals for periodic leakage rate testing of radioactive material transportation packagings

This paper describes methodologies that may be used to extend the intervals applied to the periodic leakage rate testing of certified type B transportation packagings that are loaded but not immediately shipped. In some cases, the packagings may be held in interim storage for more than 1 year, and the immediate goal is to extend the leakage rate testing interval from 1 up to as many as 5 years. The extended intervals are predicated on the basis of acceptable results of long term O ring performance tests and continuous monitoring of environmental conditions of the packagings provided by the ARG-US radio frequency identification (RFID) system. Preliminary results obtained from field testing and applications of the ARG-US RFID system to date indicated that the system is reliable and that the packaging ambient temperature can be monitored and recorded by the RFID tag sensors even when the packagings were away and outside the range of the RFID reader. Extending the intervals between the periodic leakage rate testing of the packagings enhances safety by reducing handling and radiation exposure to workers and cuts annual operating costs during the storage phase of such packagings by US$2500–3000 per
Neural response during explicit and implicit face processing varies developmentally in bipolar disorder

Both children and adults with bipolar disorder (BD) exhibit face emotion labeling deficits and neural circuitry dysfunction in response to emotional faces. However, few studies have compared these groups directly to distinguish effects of age and diagnosis. Such studies are important to begin to elucidate the developmental trajectory of BD and facilitate its diagnosis, prevention and treatment. This functional magnetic resonance imaging study compares 41 individuals with BD (19 children; 22 adults) and 44 age-matched healthy individuals (25 children; 19 adults) when making explicit or implicit judgments about angry or happy face morphs across a range of emotion intensity. Linear trend analyses revealed that BD patients, irrespective of age, failed to recruit the amygdala in response to increasing angry face. This finding was no longer significant when the group was restricted to euthymic youth or those without comorbid attention deficit hyperactivity disorder although this may reflect low statistical power. Deficits in subgenual anterior cingulate modulation were observed in both patient groups but were related to implicit processing for child patients and explicit processing for adult patients. Abnormalities in face emotion labeling and the circuitry mediating it may be biomarkers of BD that are present across development.
Stage of development and licensing university inventions

The paper analyses the correlation between the licensing activity by start-ups and established firms and the inventions’ stages of development. Using a new variable to characterise the inventions, stage of development, the paper also study the correlation between this variable and two other outcomes: patenting activity and royalty generation. The decision of firms to license at various stages of development could be affected by comparative advantage principle or by asymmetry of information. The main results show that the relative likelihood of licensing by start-ups to licensing by established firms is lower for more advanced stage inventions relative to earlier stage inventions. The results regarding the change in relative likelihood ratio across stages of development also hold when other outcome variables, like patenting and royalty creation are used.