cssi/SciSciGPT-SciSciNet huggingface dataset:
Comparison of triceps surae structural stiffness and material modulus across sex

Abstract Background. Dynamic joint stability is derived, in part, from active muscle stiffness. Previous research has identified greater structural musculotendinous stiffness in males than in females, suggesting potential sex differences in joint stability. However, structural stiffness is influenced by anthropometrics, and it is currently unclear if sex differences in musculotendinous stiffness are purely functions of anthropometrics or related to additional factors. The purpose of this investigation was to compare structural stiffness and material modulus of the triceps surae between sexes to determine the relative influence of anthropometrics. It was hypothesized that males would demonstrate greater structural stiffness and material modulus. Methods. Twenty male and 20 female individuals volunteered for participation. Active triceps surae structural stiffness was estimated from the damped frequency of oscillation of the shank about the ankle. Material modulus was calculated as the ratio of stress to strain, derived from estimates of triceps surae length and physiological cross-sectional area. Findings. Structural stiffness was significantly greater in males [mean (SD)] [137.41 (26.99) N/cm] than females [91.06 (20.10) N/cm]. Similarly, material modulus was significantly greater in males [2778.51 (549.95) Pa] than females [1968.58 (439.61) Pa]. Interpretation. Greater structural stiffness in males identified in previous literature appears to be a true phenomenon. Identification of greater material modulus in males suggests that these differences are likely attributable to sex differences in tendon stiffness and muscle architecture. These results indicate that male musculature is more effective at resisting changes in its length, a finding which may have implications for joint stability.
Coenzyme B12-dependent enzymes in potatoes: Leucine 2,3-aminomutase and methylmalonyl-coa mutase

Abstract Extracts of potato tubers contain endogenous activities of two coenzyme B 12 -dependent enzymes, leucine 2,3-aminomutase and methylmalonyl-CoA mutase. These activities are stimulated by the addition of coenzyme B 12 and are inhibited by intrinsic factor. The inhibition is overcome by coenzyme B 12 .
Prèsence de Lord Byron dans "Prochain épisode" d'Hubert Aquin

Le present article s’interesse a la presence, obsedante et obsessionnelle, de la figure mythique de Lord Byron dans Prochain episode d’Hubert Aquin. Plus qu’une reference culturelle parmi d’autres, elle sera consideree comme le point focal de toutes les allusions litteraires et historiques du roman, qu’on pourrait definir comme la quete d’une identite nationale, romantique et revolutionnaire dont Byron est la mesure. Cette importance constante accordee a la vie et aux oeuvres de Byron et a « l’Hotel d’Angleterre », ou il aurait occupe une chambre et ecrit Le prisonnier de Chillon en 1816, avant d’aller trouver la mort en route pour s’engager dans « la revolution nationale des Grecs », met a jour sur ce qu’il faut bien appeler l’anglophilie d’Hubert Aquin.
High Resolution Absorption Spectroscopy using Externally Dispersed Interferometry

We describe the use of Externally Dispersed Interferometry (EDI) for high-resolution absorption spectroscopy. By adding a small fixed-delay interferometer to a dispersive spectrograph, a precise fiducial grid in wavelength is created over the entire spectrograph bandwidth. The fiducial grid interacts with narrow spectral features in the input spectrum to create a moire pattern. EDI uses the moire pattern to obtain new information about the spectra that is otherwise unavailable, thereby improving spectrograph performance. We describe the theory and practice of EDI instruments and demonstrate improvements in the spectral resolution of conventional spectrographs by a factor of 2 to 6. The improvement of spectral resolution offered by EDI can benefit space instruments by reducing spectrograph size or increasing instantaneous bandwidth.
User interface paradigms for patient-specific surgical planning: lessons learned over a decade of research

This paper covers work in virtual reality-based, patient-specific surgical planning over the past decade. It aims to comprehensively examine the user interface paradigms and system designs during that period of time and to objectively analyze their effectiveness for the task. The goal is to provide useful feedback on these interface and implementation paradigms to aid other researchers in this field. First, specialized systems for specific clinical use were produced with a limited set of visualization tools. Later, through collaboration with NASA, an immersive virtual environment was created to produce high-fidelity images for surgical simulation, but it underestimated the importance of collaboration. The next system, a networked, distributed virtual environment, provided immersion and collaboration, but the immersive paradigm was found to be of a disadvantage and the uniqueness of the framework unwieldy. A virtual model, workbench-style display was then created using a commercial package, but limitations of each were soon apparent. Finally, a specialized display, with an integrated visualization and simulation system is described and evaluated. Lessons learned include: surgical planning is an abstract process unlike surgical simulation; collaboration is important, as is stereo visualization; and that high-resolution preoperative images from standard viewpoints are desirable, but interaction is truly the key to planning.
Sonographic demonstration of hypoplasia of the middle phalanx of the fifth digit: A finding associated with Down syndrome

Sixty percent of neonates with Down syndrome have hypoplasia of the middle phalanx of the fifth digit. We demonstrate this finding sonographically between 17 and 20 weeks' gestation in four of five fetuses with Down syndrome. The appearance of this abnormal phalanx as well as the abnormal curvature of the fifth digit is described.
Ultrasound-assisted emulsion polymerization of methyl methacrylate and styrene

In this article, we report on the effect of using ultrasound during emulsion polymerization. This work differs somewhat from that previously reported in that ultrasound is used in conjunction with conventional initiators. The aim is to observe the changes in the nature of polymerization and the synthesized polymer. In this work, reaction conditions and compositions typical of conventional emulsion polymerization are used. Azo-bisisobutyronitrile and potassium per sulfate are the initiators used. The initial indication is that the rate of polymerization and the final conversion are higher when ultrasound is introduced into the polymerization system. This effect is more pronounced at lower temperatures (50°C) and low initiator concentrations (0.01%). At higher temperatures (70°C) the polymerization rate is seemingly unaffected by the use of ultrasound. The final product in all the experiments is a latex. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 101–104, 2000
Localized Load-Sharing Rules and Markov-Weibull Fibers: A Comparison of Microcomposite Failure Data with Monte Carlo Simulations

Monte Carlo simulations are compared with strength data from carbon fibers and composites made from similar fibers, in order to investigate several issues concerning the failure of fibrous composite materials under tensile load. Failure of,"bundles" consisting of up to 1000 fibers under several different localized load-sharing rules and two different models for fiber strength is simulated, and the chain-of-bundles model is used to simulate tows of varying gauge lengths. The relationships of composite strength, Weibull shape inflation and ineffective length are investigated for the new models. The issues of volume effects and critical crack growth are also discussed.
Cooperation In Group Treatment Programs for Incarcerated Adolescents1

Group treatment programs for incarcerated adolescents attempt to use the social influence of peer groups as a means both for generating acceptance of treatment goals and for creating pro-social change. On the basis of social psychological research in laboratory and educational settings, we predicted that group cooperation plays a pivotal role in these programs. A hypothesized path model was estimated through pooled time series and cross section analysis of three waves of data for 45 groups at four institutions. There was close agreement between path estimates from an analysis of average levels and an analysis of change, and both strongly supported the hypothesized model. Results indicate that coercive control decreases cooperation and that cooperation leads to attraction to the group and prevents delinquent norms. Cooperation also has an indirect effect on acceptance of the program, mediated by attraction to the group.
Determination of Micro Channels Die Texturing for Enhancing Tribological Conditions in Tube Hydroforming

Tube hydroforming is a process that is used to manufacture rigid light-weight parts with complex cross sections by applying an internal hydraulic pressure, in combination with axial feeding or axial compressive loading. Tribological conditions in tube hydroforming (THF) are extremely important, since these conditions have a high influence in the final geometric characteristics and mechanical properties of the part formed by the THF process. In this study, the main objective is to develop a surface texture (which is composed of engraved micro channels) that will improve Tribological conditions at the die/tube interface during the expansion process in tube hydroforming. The characteristic material movement that occurs under a desired state of Tribological conditions can be used in order to design a die textured surface. Therefore, observation of this “trend” is of paramount importance for selecting the parameters that will yield a proper design (e.g. micro channel depth, channel geometry, engraved channel density). More specifically, instantaneous local material velocities, local surface enlargement and the state of stress can be observed via numerical simulations. This paper present strategies and preliminary analysis for determining micro channel die texturing to enhance tribological condition in THF.Copyright © 2005 by ASME
Studies into the interelement matrix effect in inductively coupled plasma spectrometry

Abstract Radially-resolved maps of calcium atom and ion emission and calcium atom and ion number densities have been obtained in the presence and absence of several concomitant elements. These concomitants include cesium, barium, lithium, aluminum, thallium, silver, magnesium and zinc. In addition, maps of electron concentration, electron temperature and gas-kinetic temperature are given for an analyte-only (Ca) plasma. The findings suggest the interelement interference effect to be the result of at least three major processes operating simultaneously: lateral-diffusion (i.e. particle-volatilization) changes, shifts in analyte-ionization equilibrium, and differences in collisional excitation efficiency. Expanded lateral diffusion caused by enhanced particle volatility explains the greater number of analyte species in the off-axis plasma zones when an interferent is added to the sample. The combined concomitant-induced effects of expanded lateral diffusion and shift in ionization equilibrium can be used to describe a drop in analyte ion concentration that occurs in the central channel but with little or no change in the Ca atom number density, Enhanced collisional excitation caused by small increases in the plasma electron number density and electron temperature result in elevated analyte emission intensities in some plasma zones. Also, a charge-transfer mechanism is described which might result in the direct production and excitation of Ca ions from molecular analyte species.
Selective action of (-)-2-oxa-4-aminobicyclo[3.1.0]hexane-4,6-dicarboxylate (LY379268), a group II metabotropic glutamate receptor agonist, on basal and phencyclidine-induced dopamine release in the nucleus accumbens shell.

Abstract The effect of the group II metabotropic receptor agonist (−)-2-oxa-4-aminobicyclo[3.1.0]hexane-4,6-dicarboxylate (LY379268), on basal and phencyclidine-induced dopamine efflux were measured in the shell and core subdivisions of the nucleus accumbens—regions which are associated with limbic and motor functions, respectively. Extracellular levels of dopamine were measured using microdialysis in conscious animals, and LY379268 was delivered locally by inclusion in the artificial cerebrospinal fluid (aCSF) flowing through the microdialysis probe. Local administration of LY379268 in the concentration range 10 nM–10 μM reduced basal levels of dopamine in the nucleus accumbens shell, whilst having no effect in the nucleus accumbens core. In the nucleus accumbens shell, basal levels were reduced to approximately 60% compared to the pre-injection control, with a maximal reduction occurring at concentrations of LY379268 ≥100 nM. The response to LY379268 (100 nM) was reversible, with levels returning to baseline following its removal from the aCSF. In a separate experiment, local perfusion of the nucleus accumbens shell with LY379268 (at both 1 and 10 μM) reduced the magnitude of the response to a subsequent systemic administration of phencyclidine (5 mg/kg i.p.). The reduction in the peak dopamine response was only evident with doses of LY379268 that also reduced basal dopamine efflux—LY379268 being ineffective against PCP at 10 nM. However, in animals pre-treated with LY379268 at 1 or 10 μM, PCP still evoked a dopamine response, and in these animals the relative extent of the response was not significantly different between the respective treatment groups. In contrast, in the nucleus accumbens core the magnitude of the dopamine response to PCP was unaffected by local application of LY379268 (at 1 or 10 μM). Our data suggest that within the nucleus accumbens, there exists a distinct regional difference in the control of dopamine release by group II mGluRs, with the nucleus accumbens shell being preferentially affected. Moreover, the selective action of LY379268 on dopamine levels in the nucleus accumbens shell may have implications for the potential antipsychotic activity of group II mGluR agonists.
Transvaginal culdosuspension: technique and results.

Abstract Objectives. Numerous techniques have been described for supporting the vaginal vault after enterocele repair and hysterectomy. We describe a transvaginal culdosuspension that obliterates the cul-de-sac and supports the vaginal cuff high on the levator plate. The normal vaginal axis is restored, and adequate vaginal depth is provided for normal sexual activity. Methods. One hundred four patients, aged 48 to 90 years (mean age 71), underwent transvaginal culdosuspension in conjunction with enterocele repair (62 patients), vaginal hysterectomy (20 patients), or both (22 patients). Two culdosuspension sutures support the vaginal vault to the origin of the sacrouterine and cardinal ligaments, and the cul-de-sac is obliterated with two pursestring sutures. Concomitant prolapse was repaired in 82 patients, bladder neck suspension in 50, cystocele repair in 45, and rectocele repair in 76. Results. One hundred patients were followed up at a mean of 17.3 months (range 6.5 to 35). Recurrence of enterocele or vault prolapse occurred in 4 patients. All patients who had preoperative stress incontinence were cured of leakage. Complications were rare, and there were no instances of vaginal foreshortening, urinary retention, vaginal skin necrosis, bladder perforation, or rectovaginal fistula. Conclusions. Transvaginal culdosuspension is a safe and effective procedure for treating and preventing enterocele and vaginal vault prolapse. This technique restores the normal vaginal depth and axis, resulting in a sexually functional vagina.
Genesis and Evolution of the Use of Polarization in Remote Sensing of Atmospheres and Oceans

We will give an overview of the importance of polarization sensing in the atmosphere and ocean. The Stokes vector/Mueller matrix formalism is used to show how the method gives distinct advantages over ordinary radiance sensing.
Rhetoric's Stepchildren: Ancient Rhetoric and Modern Creative Writing

Abstract This article attempts to connect modern issues in creative writing pedagogy with the ancient theories of rhetoric. Specifically, I engage the ideas of tribe (natural ability), techne (art or craft), and empeiria (learning by doing) in relation to creative writing theory. The modern concerns with writers, and the positioning in the classroom of teachers who either look for the class ‘star’ with natural ability, or those who attempt to teach all of the students with a fundamental belief that writing is a craft that can be taught to everyone with practice. These views are not that uncommon in the texts of ancient rhetoric. In teaching oratory in the Greek city-states, and in the Roman Empire, the great teachers of the day – Aristotle, Isocrates, and even Quintilian wrestled with the problematic views of natural ability in the orator. These issues have plagued teachers for the past two thousand years. Drawing on both classical rhetorical theory, and modern creative writing pedagogy, my essay addresse...
On the mechanism of retrovirus-induced avian lymphoid leukosis: deletion and integration of the proviruses

Abstract There is considerable evidence that infection by avian lymphoid leukosis viruses can led to tumor development in the target organ of the host. The mechanism by which virus-induced oncogenic transformation occurs, however, is not clearly understood. As a first step toward deciphering this process, we have characterized the proviruses of the lymphoid leukosis viruses in DNAs extracted from the leukotic and metastatic tumors by using restriction enzyme digestion and filter hybridization analysis with radioactive probes specific for the infecting genome. Our results indicate (i) that lymphoid leukosis tumors are clonal in origin; (ii) that there are multiple sites in the cellular genome of the target tissue where the virus DNA can integrate and that, in the majority of the tumors, at least one such site of each tumor is adjacent to a cellular sequence related to the oncogene of MC-29 virus; and (iii) that deletions and other structural alterations in the proviral DNA may facilitate tumorigenesis.
Allyl Halide (Macro)initiators in ATRP : Synthesis of Block Copolymers with Polyisobutylene Segments

Allyl halides (allyl-X) and polyisobutylene with allyl halide end group (PIB-allyl-X where X = Cl, Br) were investigated as (macro)initiators in atom transfer radical polymerization (ATRP). Studies with low molecular weight allyl halide initiators that model the PIB-allyl-X macroinitiator were performed first. Polymerization of styrene (St) using allyl halides in the presence of CuX/4,4′-di(5-nonyl)-2,2′-bipyridine (dNbpy) catalyst was controlled, but polystyrene with lower polydispersity was obtained with the Br-based initiator−catalyst system. ATRP of methyl methacrylate (MMA) initiated by allyl halides was not as successful. Polymerization of MMA with allyl-Cl and CuCl/dNbpy catalyst resulted in polymer with molecular weight 4 times higher than the predicted value. The polymerization initiated by allyl-Br in the presence of CuCl/dNbpy catalyst was better controlled but still resulted in polymers with molecular weights 2 times higher than the theoretical values. The addition of 10 mol % St to MMA signif...
Using target audience feedback to inform a technology-delivered intervention: The development of a Web-based tool for chronic pain patients

incentives and long-term sustainability, we are currently developing a videogame-based CM intervention. Smokers will be able to earn game-based resources, or access to special features in the game, in place of monetary incentives. Videogame-based CM will promote widespread access to an innovative, fun, sustainable intervention at a relatively low cost, thereby offering the potential to have a substantial public health impact.
Improving the accuracy of ab initio methods with summation approximants and singularity analysis

The accuracy of Moller–Plesset (MP) perturbation theory and coupled-cluster (CC) theory can be significantly improved, at essentially no increase in computational cost, by using summation approximants that model the way in which these theories converge to the full configuration interaction limit. Approximants for MP4 and CCSD(T) are presented, their size scaling is analyzed, and the functional analysis of the MP energy, on which the MP4 approximant is based, is discussed. The MP approximants are shown to have a form that is appropriate for describing resonance energies. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Update and perspective on noninvasive respiratory muscle aids. Part 2: The expiratory aids.

B1PAP=bilevel positive airway pressure; CAH’chromc alveolar hypoventilation; CNEP=continuous negative extrathoracic pressure; CPAP=continuous positive airway pressure; DMD=Duchenne muscular dystrophy; EPAP=expiratory positive airway pressures; EPR electrophrenic respiration; GPB=glossopharyngeal breathing; IAPVintermittent abdominal pressure ventilator, ffAP inspiratory positive airway pressures; IPPBintermittent positive pressure breathing; IPPVintennittent positive pressure ventilation; MI-E=mechanical insufflation-exsufflation; NPBVs=negative pressure body ventilators; PCEF=peak cough expiratory flows; RTIs= respiratory tract infections; VCvital capacity
Hepatic Arterial Waveforms on Early Posttransplant Doppler Ultrasound

OBJECTIVES To determine the significance of spectral Doppler hepatic artery waveforms obtained in the first 10 days after primary liver transplantation and to determine the best early predictor of hepatic arterial thrombosis (HAT). SUBJECTS AND METHODS A total of 645 patients were retrospectively followed up to 1 year after liver transplantation. Doppler waveforms of the hepatic arteries were categorized as normal, abnormally elevated, not visualized, or with resistive index (RI) <0.5 on all examinations performed within the first 10 days. Waveforms were then correlated with patient outcomes within 1 year. RESULTS Of the 645 patients, 83 (12.8%) had nonvisualization of at least one hepatic artery on Doppler evaluation and 56 (8.7%) developed HAT or stenosis within the first year after transplantation. Odds ratios (ORs) demonstrate that a single nonvisualized hepatic artery (OR, 9.66; 95% confidence interval [CI], 4.51-20.70) has a much higher incidence of HAT in the first 10 days after transplantation compared to low RI (OR, 1.93; 95% CI, 0.77-4.79)] or high RI (OR, 1.06; 95% CI, 0.44-2.55]. The loss or reversal of diastolic flow on Doppler ultrasound performed in the first 10 days after transplantation does not seem to correlate with active or impending HAT. CONCLUSION Absence of hepatic arterial flow Doppler signal in the first 10 days after liver transplantation is associated with higher incidence of thrombosis than previously demonstrated, whereas persistently high diastolic flow early on seems to be more significant and leads to further hepatic arterial complications than decreased diastolic flow.
G protein-coupled receptors self-assemble in dynamics simulations of model bilayers.

Many integral membrane proteins assemble to form oligomeric structures in biological membranes. In particular, seven-transmembrane helical G protein-coupled receptors (GPCRs) appear to self-assemble constitutively in membranes, but the mechanism and physiological role of this assembly are unknown. We developed and employed coarse-grain molecular dynamics (CGMD) models to investigate the molecular basis of how the physicochemical properties of the phospholipid bilayer membrane affect self-assembly of visual rhodopsin, a prototypical GPCR. The CGMD method is a mesoscopic simulation technique in which groups of atoms are mapped to particles on the basis of a four-to-one rule. This systematic reduction of the degrees of freedom allows for computationally efficient calculation of the structure and dynamics of molecular assemblies for larger time and length scales than accessible to atomistic models, providing here an unprecedented view of spontaneous protein assembly in biomembranes. Systems with up to 16 rhod...
Deduction of Spinal Loading from Vertebral Body Surface Strain Measurements

The lumbar intervertebral disc, the apparent nexus of low back pain, undergoes biomechanical changes during its degeneration which are as yet poorly understood. In an effort to ultimately examine in vivo daily activity loads across intervertebral discs, we engaged in the following methodological study. The aim of this research was to correlate vertebral body surface strains with the loads across a lumbar spine segment. Rosette strain gages were affixed anterolaterally on L4 and L5 in a macaque monkey model. These tissues were loaded axially and with sagittal plane moments and the principal strains were compared with the applied loads. Predictable axial and sagittal plane loading profiles were found for similar strain measurements and the system was found to be robust through freezing and thawing. These results support future research aimed at quantifying the in vivo disc mechanics of healthy and degenerate tissues in an attempt to develop prevention or intervention strategies to ease those afflicted with low back pain.
New generalized least squares estimation algorithm for system identification

This paper presents modified formulations of the generalized least squares estimation algorithm for system parameter identification. Two sets of results are derived: First the existing algorithm is reformulated by eliminating the intermediate filtering procedures and introducing the system's input-output correlation matrices. Then it is shown that the new algorithm can be conveniently simplified to a form which does not require repeated matrix inversions.
Outcomes after major vascular surgery: The patients' perspective

Surgical outcomes are traditionally defined by rates of morbidity and mortality, as well as the success with which operative objectives are met. Although quality of life after surgery bas been sporadically mentioned in the literature since the turn of the century, far greater emphasis has been placed on traditional outcome measures. As the population ages and technological advances permit high-risk interventions in selected elderly patients, the assessment of outcomes with respect to quality of life has become increasingly relevant. To assess quality of life and surgical outcome, 15 patients undergoing simultaneous bilateral renal revascularization at Yale-New Haven Hospital were retrospectively studied. Fifteen charts were reviewed for data on length of hospital stay, number of days in the intensive care unit, operative morbidity, and short- and long-term results. The SF-36, a previously validated health status questionnaire, was used to survey the 11 long-term survivors. Telephone surveys were conducted by a vascular nurse. Of the 11 long-term survivors, nine patients rated their health as good to excellent (eight rated it the same or better than before surgery), eight had no or minimal physical disability, and 10 remained as involved socially as previously. The SF-36 appears to be an effective instrument for assessing postoperative quality of life. It was concluded that this group of patients was satisfied with the outcome of surgery, suggesting that major vascular surgical interventions could be undertaken in selected elderly patients without significant adverse impact on quality of life.
A Survey to Investigate Student Drinking Norms at Foxfield

Drinking plays a role in the social activities of University of Virginia (UVA) students, including the annual Foxfield Horse Races. However, no data gauge the levels of binge, or high-risk, drinking at Foxfield. A web-based survey has been developed to begin to measure the drinking norms at Foxfield with the hopes of using the data to create a safer environment at future events. Using a limited sample of 78 students, the preliminary data show that students drink more at Foxfield than each day of a normal week. Students also report drinking more and longer at Foxfield than during Halloween and football games (events known to be large social events at UVA). 66% of respondents also reported at least one negative consequence as a result of another's drinking and 68% reported at least one negative consequence as a result of his own drinking. This work helps to lay the groundwork for a large sample data collection after the 2006 running of the Foxfield Races on April 29th.
Review of Reductive Leaching of Iron by Anaerobic Bacteria

Leaching of iron, either as an impurity to be removed or as a metal to be recovered, requires a different approach than that of the oxidative leaching that dominates biohydrometallurgy of other metals. In particular, the significant increase in solubility that results from reducing Fe3+ to Fe2+ suggests that a reductive leaching process is most suitable. A wide range of anaerobic iron-reducing bacteria have been demonstrated to exist in the last few decades, which reduce Fe3+ to Fe2+ as part of their respiration. More of these organisms are continually being discovered, and many of these have promise for reductive bioleaching of iron. This review examines the many types of bacteria that have been demonstrated to reduce and solubilize iron, and the environments where such organisms can be found. The cultivation requirements of these organisms are also discussed, along with descriptions of the work that has been done to apply them to specific applications. These applications include decolorization of kaolin...
Modeling co-located servers and dispatch ties in the hypercube model

Abstract Several spatially distributed queuing models, notably the hypercube models, have been developed for emergency vehicle service systems. None of these models specifically address the issue of dispatch preference ties that is commonly encountered in systems with co-located units; e.g. ambulance systems. A variation of the hypercube model that accommodates preference ties is developed and applied to the emergency medical system of Greenville County, S.C.
Some Properties of r-Process Accretion Disks and Jets

In a core-collapse supernova event a rapidly rotating neutron star is formed (in the more massive stars this may subsequently collapse to a black hole). Recent studies have indicated that an intrinsic feature of the subsequent explosion is the flood of neutrinos and antineutrinos (of the three flavors) that will heat and transfer momentum to the overlying envelope and expel it. They are also expected to expel a neutron-dominated plasma in a wind from the surface of a simple neutron star lacking rotation and magnetic fields. However, because of the rapid rotation, the magnetic field that connects the neutron star to the overlying envelope should be wrapped into a toroid and the ejected plasma should be incorporated into the accretion disk formed around the star. Simulations of collapsing stellar cores have also shown that rotational flattening will produce a small accretion disk. Such accretion disks in astrophysical objects always appear to form a pair of axial jets. Here the disk plasma should be accelerated out of the disk in the jets with a velocity of the order of 0.5c. The operation of the r-process in this kind of accretion disk and the ejection of the products in the jets has been studied. The critical density in the accretion disk lies in the range 1011-1013 gm cm-3, where nuclear statistical equilibrium (with balance between beta decay and capture) maintains the nuclei well beyond the conventional neutron drip line, with free neutron/nucleus ratios in the tens to the thousands. The r-process takes place while this material moves toward the base of the jets and beta imbalance allows the proton charge number to increase at a rate of several per second. The plasma coming from the higher densities undergoes fission recycling and produces nuclei mainly at and above A = 132, while the plasma from lower densities produces the lower part of the r-process yields. The jets should also expel material from the still lower density part of the disk in which no r-process has occurred. The interaction of the jets with the surrounding expanding supernova envelope is discussed. Phenomena here involve the spallation formation of the LiBeB elements and the formation of deuterium by similar spallation on helium or by neutron diffusion out of the jets if there is an outer hydrogen region in the expanding envelope. This is probably the origin of the 10Be found as an extinct radioactivity in primitive solar system material, arising from the core-collapse supernova that appears to have triggered the collapse of a molecular cloud core to form the primitive solar nebula, and of the deuterium enhancement at the galactic central region of star formation. The jets constitute a natural way to produce the large variations in abundances detected in the youngest generation of stars. The r-process jets are identified with the gamma-ray bursters as a result of diffusion of gamma rays from the jets, arising from beta decay of the r-process products, and their afterglows are identified with the interactions of the jets in penetrating through the supernova envelopes.
N-linked Glycan Structures and Their Expressions Change in the Blood Sera of Ovarian Cancer Patients

Glycosylated proteins play important roles in a broad spectrum of biochemical and biological processes, and prior reports have suggested that changes in protein glycosylation occur during cancer in...
Transitioning to and from the novel oral anticoagulants: a management strategy for clinicians

Vitamin K antagonists have been the only available oral anticoagulant therapy for decades until the recent introduction of novel (new) oral anticoagulants. This breakthrough provides patients with alternative treatment choices that have predictable pharmacokinetics and do not require routine coagulation monitoring. Though more convenient from patient perspective, these drugs have distinct pharmacological properties that are particularly important to recognize when transitioning anticoagulant therapies. The following review focuses on transitioning to and from the novel oral anticoagulants, employing a practical pharmacokinetic- and pharmacodynamic-based approach.
Joining the Army of Proteasome Inhibitors

An article in this issue of Chemistry & Biology (Hines et al., 2008) and a recent study in Nature (Groll et al., 2008) establish three natural products as novel proteasome inhibitors. These inhibitors, discovered in an unusual way, reveal a different mechanism of proteasome inhibition and suggest new therapeutic application of its inhibitors.
Synthetic approaches to rhodomycinone and olivin

Les intermediaires de synthese sont prepares par reaction de Diels Alder suivie d'une cyclisation de Friedel-Crafts
Teacher beliefs and practices relating to development in preschool: importance placed on social–emotional behaviours and skills

Preschool teachers' beliefs relating to the importance of social–emotional competence and teacher practices that support children's competence were investigated through surveys and focus groups. Survey results indicated that Head Start and public school pre-K teachers placed higher importance on social–emotional behaviours and skills than on early math and language and literacy behaviours and skills and reported a variety of practices to promote prosocial skills, pretend play, and friendships. Practices that support prosocial skills ranged from setting the tone of the social environment to responding to situations that arose. Similarly, practices that support pretend play focused on setting up pretend play scenarios and helping children play in those scenarios. Finally, practices to support friendships involved practices that may set the stage for friendship development, facilitating dyadic and small group interactions, and involving parents. Results are discussed in terms of connections with previous res...
Manifestations of Bose and Fermi Statistics on the Quantum Distribution Function for Systems of Spin-0 and Spin-1/2 Particles

We consider the manifestations of Bose and Fermi statistics on the original quantum distribution function. Initially, we consider some general symmetry properties of the density matrix. Next, we convert these results into distribution-function language for the case of a system of spin-0 particles. Finally, we consider a system of spin-1/2 particles, for which we treat the combined effects of both spin and statistics.
Positive ion composition from a rocket-borne mass spectrometer

D region positive ion composition measurements by rocket-borne quadrupole mass spectrometer, discussing downleg and upleg data
Chromophore packing leads to hysteresis in GFP.

Abstract Green fluorescent protein (GFP) possesses a unique folding landscape with a dual basin leading to the hysteretic folding behavior observed in experiment. While theoretical data do not have the resolution necessary to observe details of the chromophore during refolding, experimental results point to the chromophore as the cause of the observed hysteresis. With the use of NMR spectroscopy, which probes at the level of the individual residue, the hysteretic intermediate state is further characterized in the context of the loosely folded isomerized native-like state {Niso} predicted in simulation. In the present study, several residues located in the lid of GFP indicate heterogeneity of the native states. Some of these residues show chemical shifts when the native-like intermediate {Niso} responsible for GFP's hysteretic folding behavior is trapped. Observed changes in the chromophore are consistent with increased flexibility or isomerization in {Niso} as predicted in recent theoretical work. Here, we observed that multiple chromophore environments within the native state are averaged in the trapped intermediate, linking chromophore flexibility to mispacking in the trapped intermediate. The present work is experimental evidence for the proposed final “locking” mechanism in GFP folding forming an incorrectly or loosely packed barrel under intermediate (hysteretic) folding conditions.
Xylella fastidiosa Infection and Ethylene Exposure Result in Xylem and Water Movement Disruption in Grapevine Shoots

It is conventionally thought that multiplication of the xylem-limited bacterium Xylella fastidiosa ( Xf ) within xylem vessels is the sole factor responsible for the blockage of water movement in grapevines ( Vitis vinifera ) affected by Pierce9s disease. However, results from our studies have provided substantial support for the idea that vessel obstructions, and likely other aspects of the Pierce9s disease syndrome, result from the grapevine9s active responses to the presence of Xf , rather than to the direct action of the bacterium. The use of magnetic resonance imaging (MRI) to observe the distribution of water within the xylem has allowed us to follow nondestructively the development of vascular system obstructions subsequent to inoculation of grapevines with Xf . Because we have hypothesized a role for ethylene produced in vines following infection, the impact of vine ethylene exposure on obstruction development was also followed using MRI. In both infected and ethylene-exposed plants, MRI shows that an important proportion of the xylem vessels become progressively air embolized after the treatments. The loss of xylem water-transporting function, assessed by MRI, has been also correlated with a decrease in stem-specific hydraulic conductivity ( K S ) and the presence of tyloses in the lumens of obstructed water conduits. We have observed that the ethylene production of leaves from infected grapevines is greater than that from healthy vines and, therefore, propose that ethylene may be involved in a series of cellular events that coordinates the vine9s response to the pathogen.
White dwarfs and the ages of open clusters

Open clusters provide the ideal environment for the calibration of ages determined from main sequence evolutionary theory (via cluster isochrones) and ages determined from white dwarf cooling theory. In an effort to measure more precise cluster ages, our group has developed a new technique using Bayesian statistics. Here we will discuss new capabilities of the technique, as well as the first application to real data, using the Hyades as a test case. Because the faintest white dwarfs have likely evaporated from the Hyades, we also demonstrate the first successful application of the bright white dwarf technique for deriving ages from the bright cluster white dwarfs alone.
Newly developed polymorphic microsatellite markers for frogs of the genus Ascaphus

Thirteen polymorphic microsatellite loci were identified and developed for the coastal tailed frog, Ascaphus truei, from sites within the Olympic Peninsula of Washington, USA. These tetranucleotide repeat loci were highly variable, averaging 19 alleles per locus and expected heterozygosity of 0.91. In addition, these loci cross-amplify in the sister species, Ascaphus montanus. These markers will prove useful in identifying fine-scale genetic structure, as well as provide insight into the evolution and conservation of this group across fragmented landscapes.
Automatic data partitioning for the agere payload plus network processor

With the ever-increasing pervasiveness of the Internet and its stringent performance requirements, network system designers have begun utilizing specialized chips to increase the performance of network functions. To increase performance, many more advanced functions, such as traffic shaping and policing, are being implemented at the network interface layer to reduce delays that occur when these functions are handled by a general-purpose CPU. While some designs use ASICs to handle network functions, many system designers have moved toward using programmable network processors due to their increased exibility and lower design cost. In this paper, we describe a code generation technique designed for the Agere Payload Plus network processor. This processor utilizes a multi-block pipeline containing a Fast Pattern Processor (FPP) for classification, a Routing Switch Processor (RSP) for traffic management and a third block, the Agere Systems Interface (ASI), which provides additional functionality for performance. This paper focuses on code generation for the clustered VLIW compute engines on the RSP. Currently, due to the real-time nature of the applications run on the APP, the programmer must lay out and partition the application-specific data by hand to get good performance.The major contribution of this paper is to remove the need for hand partitioning for the RSP compute engines. We propose both a greedy code-generation approach that achieves harmonic mean performance equal to code that has been hand partitioned by an application programmer and a genetic algorithm that achieves a harmonic mean speedup of 1.08 over the same hand-partitioned code. Achieving harmonic mean performance that is equal to or better than hand partitioning removes the need to hand code for performance. This allows the programmer to spend more time on algorithm development.
Parametric wave field coding for precomputed sound propagation

The acoustic wave field in a complex scene is a chaotic 7D function of time and the positions of source and listener, making it difficult to compress and interpolate. This hampers precomputed approaches which tabulate impulse responses (IRs) to allow immersive, real-time sound propagation in static scenes. We code the field of time-varying IRs in terms of a few perceptual parameters derived from the IR's energy decay. The resulting parameter fields are spatially smooth and compressed using a lossless scheme similar to PNG. We show that this encoding removes two of the seven dimensions, making it possible to handle large scenes such as entire game maps within 100MB of memory. Run-time decoding is fast, taking 100μs per source. We introduce an efficient and scalable method for convolutionally rendering acoustic parameters that generates artifact-free audio even for fast motion and sudden changes in reverberance. We demonstrate convincing spatially-varying effects in complex scenes including occlusion/obstruction and reverberation, in our system integrated with Unreal Engine 3™.
THE MEDITERRANEAN COMMITTEE AND FRENCH NORTH AFRICA, 1935–1940

(1990). The Mediterranean Committee and French North Africa, 1935–1940. The Historian: Vol. 53, No. 2, pp. 255-266.
Fighting the Future War: An Anthology of Science Fiction War Stories, 1914–1945. Frederic Krome, Editor. New York: Routledge, 2012.

Fighting the Future War: An Anthology of Science Fiction War Stories, 1914-1945 Frederic Krome, Editor. New York: Routledge, 2012.According to Frederic Krome, science fiction is more accurately viewed as a reflector of the present than a predictor of the future. In other words, its narrative creations mirror hopes, fears and aspirations of the time during which it was written. As such, says Krome, science fiction ought to interest historians.His contribution to the historical record is this anthology of short stories and editorials (published from the start of the First World War to the end of the Second World) that imagine what future war would be like. Primarily these writings focus on Earthbound (not interplanetary) conflicts, and all but one appeared in pulp magazines that specialized in science fiction. This thematic reader explores an era when pulps flourished and the science-fiction genre was finding its way. That way began with Hugo Gernsback.Krome provides half a dozen of Gernsback's rarely reprinted editorials and one short story from The Electrical Experimenter magazine. Although his cliched fiction is yawningly gadget-driven, his editorials are surprisingly lively. Gernsback says he is passionately intent on "firing some experimenter's imagination to work in a new direction" (30). To that end, he proposes wonderfully creative and pragmatic inventions like trench destroyers, long-distance electro-shock guns, and microphone buoys-machines that will bring wars to a quicker conclusion.Gernsback's tutelage (he controlled the most influential pulp magazines up to the 1929 Crash) fostered programmatic authors whose unsubtle, big-brained heroes defied slow-witted bureaucrats to save Americans from potentially disastrous attacks by unprincipled foreign nations. In one of his later editorials, Gernsback suggested that "the ideal pro-portion of a scientifiction [his earlier term for the genre he would later rename science fiction] story should be seventyfive per cent literature interwoven with twenty-five per cent science" (113). But the stories he wrote and many of those he edited seem to reverse that proportion.So what is an anthology to do when so many future-war stories are almost subliterary? Krome takes the courageous path less chosen. He deliberately avoids limiting his anthology to canonical literature only; he happily includes short stories that have lain unread because of pedestrian style, plotting and characters. The result for readers is double-edged: we have the joy of discovering old-fashioned ripping yarns, but also the onus of slogging through some leaden prose. …
A Quantum-Chemistry-Based Potential for a Poly(ester urethane)

We have carried out extensive high-level quantum chemistry studies of the geometry, charge distribution, conformational energies, and hydrogen-bonding energies of model compounds for a family of Estane thermoplastic urethanes (TPUs). Upon the basis of these studies, we have parametrized a classical potential for use in atomistic simulations of Estane TPUs that can also be applied directly or with minor extensions to a wide variety of polyesters and polyurethanes.