cssi/SciSciGPT-SciSciNet huggingface dataset:
COMPARATIVE STUDY OF COUPLED-MODE FLUTTER-ANALYSIS METHODS FOR FAN CONFIGURATIONS

A comparative computational study of current e utter-analysis methods, for fan geometry in subsonic e ow, is carried out to evaluate the relative advantage of the methods. The e utter characteristics are computed using the followingthreemethods:timedomain, workpercycle, andtheeigenvalueanalysis.Theeigenvalueanalysisisbased on a pulse method in combination with the ine uence coefe cient method. The aeroelastic analyses are performed using a time-accurate solver based on Euler equations. The aeroelastic characteristics of the fan are obtained by coupling the unsteady Euler equation solution with a normal-mode analysis of elastic blades. For the coupledmodee utteranalyzed,thetime-domainmethod indicated stability orinstability fasterthan theeigenvaluemethod, whereas the work-per-cycle method failed to predict the e utter. The eigenvalue method provided the results in the form of aerodynamic damping and e utter frequency for each interblade phase angle analyzed. However, it was more expensive than the time-domain method, and it was better suited for analysis with a fewer number of modes.
An Artificial Right Ventricle for Failing Fontan: In Vitro and Computational Study

Background The aim of this study is to develop a destination low-pressure artificial right ventricle (ARV) to correct the impaired hemodynamics in the failing Fontan circulation. Methods An in vitro model circuit of the Fontan circulation was created to reproduce the hemodynamics of the failing Fontan and test ARV performance under various central venous pressures (CVP) and flows. A novel geometry of the extracardiac conduit was designed to adapt to the need of the pump. The ARV was a low-pressure axial flow pump designed to produce a low suction inflow pressure and moderate outflow increase. With the power off, the passive forward gradient across the propeller is 2 mm Hg at 4.5 L/min. The ARV would require 4 watts at a rotation of 5000 rpm. To examine the shear loading on the red blood cells, virtual particles were injected upstream of the ARV inducer and tracked by computerized modeling. Results The effect of the ARV on the failing Fontan was studied at various CVP pressures and flows, and under constant values of lung resistances and left atrial pressure set respectively to 2.5 Woods Units and 7 mm Hg. The CVP pressures decreased respectively from 25, 22.5, 20, 17.5, 15, and 10 mm Hg to a minimal value of 2 to 5 mm Hg with a pump speed varying from 1700 to 4500 rpm. The pulmonary artery pressures increased moderately between 12.5 and 25 mm Hg at 4500 rpm. Cardiac output at 4500 rpm was increased by an average gain of 2 L/min. The average blood damage index was 0.92%, far below the 5% value considered to cause hemolysis. The flow structure produced by the pump was suitable. Conclusions The performance of this novel low-pressure ARV was satisfactory, showing good decrease of CVP pressures, a moderate increase of pulmonary artery pressures, adequate increase of cardiac output, and minimal hemolysis. The use of a mock Fontan model circuit facilitates device prototyping and design to a far greater extent than can be achieved using animal studies, and is an essential first step for rapid design iteration of a novel ARV device. The next steps are the manufacturing of this device, including an electromagnetic engine, a regulatory system, and further testing the device in a survival animal experiment.
Aneurysms of the posterior inferior cerebellar artery-vertebral artery complex: Variations on a theme

Aneurysms of the posterior inferior cerebellar artery-vertebral artery complex are relatively uncommon lesions. They include aneurysms at the origin of the posterior inferior cerebellar artery (PICA-VA), aneurysms on the distal artery (PICA) and aneurysms at the junction of the vertebral and basilar arteries (VA-BA). We have had the opportunity to treat 17 patients and study the radiological records of 9 additional patients in the past 8 years. The aneurysms ranged in size from 3 to 30 mm, with mean values of 10.6, 7.3, and 9 mm for PICA-VA lesions, distal PICA lesions, and VA-BA lesions, respectively. Three of the 4 VA-BA aneurysms were located at the midline, and the mean distance of the PICA-VA aneurysms from the midline was 7.6 to 9.4 mm; 2 aneurysms crossed the midline from their parent VA. The aneurysms were located slightly more often on the left side (left:right ratio, 1:2), were found more frequently in women (2.25:1), and occurred at a mean age of 50 years. Ten aneurysms at the origin of the PICA and 4 VA-BA aneurysms were treated via a lateral suboccipital craniectomy; 3 distal PICA aneurysms were exposed by a midline craniectomy. Surgery was carried out acutely in 5 patients. Tortuousness of the VA required contralateral approaches in 2 patients, an exploratory craniectomy in 1 patient, and an approach toward the dome of 1 patient with a VA-BA aneurysm. Morbidity was primarily due to cranial nerve dysfunction. There were no perioperative deaths. These aneurysms can easily be missed on initial radiographic examination; one appeared only on the second study, one was seen to grow over 16 days, and one was discovered at the level of C1 extracranially. Our radiographic and surgical approach to the treatment of these lesions is presented.
A simulation trial of traditional dispatcher-assisted CPR versus compressions--only dispatcher-assisted CPR.

Objectives. Growing evidence indicates that it may not be essential to deliver ventilations in the first few minutes of CPR. We compared time to delivery of first compression in traditional CPR with ventilations andcompressions to compression-only CPR performed by untrained laypersons assisted by a mock 911 dispatcher. Methods. This randomized-controlled simulation study included a convenience sample of English-speaking emergency department visitors during a 6-month period. Exclusion criteria were prior CPR training or physical incapacity. A cardiac arrest scenario was presented to subjects who were then provided with one of two sets of telephone CPR instructions by a mock 911 dispatcher. One group received traditional CPR instructions (TCPR) andthe second group received compression only CPR instructions (COCPR). Subjects performed CPR on a Laerdal Resusci-Anne CPR manikin andrecording strips were analyzed for frequency andquality measures. Pre-and post-test questionnaires assessed subject fatigue andtele...
Purification of a β-D-galactosidase from bovine liver by affinity chromatography

Abstract A β- d -galactosidase from bovine liver was purified to apparent homogeneity. The major purification step was affinity chromatography on a column of d -galactose attached to a Sepharose support activated with divinyl sulfone. Affinity media prepared by binding ligands to Sepharose activated with cyanogen bromide were unsuitable for purification of the enzyme, even though such media have been used to purity β- d -galactosidases from other sources. The molecular weight of the denatured enzyme was 67,000. The molecular weight of the native enzyme at pH 7.0 was 68,000, and at pH 4.5 or 5.0, was 141,000. These data suggest that the enzyme has a single, fundamental subunit with a molecular weight of 67,000, and that the enzyme exists as a monomer at pH 7.0, and a dimer at pH 4.5 or 5.0. The V max values of the enzyme with p -nitrophenyl β- d -galactoside, p -nitrophenyl β- d -fucoside, lactose, and β-Gal-(1→4)-β-GlcNAc-1→OC 6 H 4 NO 2 - p were 10,204, 11,550, 9,479, and 8,859 nmol/min/mg of protein, respectively, and the K m values for these substrates were 0.08, 14.9, 14.2, and 1.6m m , respectively. d -Galactose, β- d -galactosylamine, p -aminophenyl 1-thio-β- d -galactoside, and d -galactono-1,4-lactone were competitive inhibitors of the enzyme, with K i values of 0.9, 0.6, 0.6, and 0.8m m , respectively. The enzyme catalyzed the transfer of the d -galactosyl group from p -nitrophenyl β- d -galactoside to d -glucose. The pH optimum of the enzyme was 4.5, and the pI was 4.7.
Organization tenure as a moderator of the job satisfaction-job performance relationship

Abstract Organization tenure as a moderator of the job satisfaction-job performance relationship was examined with data from a sample of 116 technical employees in a medium-sized industrial firm. Results provide support for a moderating influence of organization tenure on the relationship between job performance and overall satisfaction, satisfaction with work, and satisfaction with supervision.
Processable conductive composites of polyaniline/poly(alkyl methacrylate) prepared via an emulsion method

Abstract Polyaniline/poly(alkyl methacrylate) composites are prepared using an emulsion pathway which involves two steps. First, an emulsion with the appearance of a gel is prepared by dispersing a chloroform solution of poly(alkyl methacrylate) and aniline in an aqueous solution of sodium dodecylsulfate (SDS). Secondly, an oxidant (sodium persulfate) dissolved in an aqueous solution of HCl is added dropwise to the emulsion with vigorous stirring in order to polymerize the aniline and to dope the polyaniline formed. The composite precipitates or is precipitated by the addition of methanol. The materials have been processed either by cold- or hot-pressing. Those prepared by hot-pressing can have electrical conductivities as high as 2 S/cm and good mechanical properties, while those prepared by cold-pressing have somewhat higher conductivities but somewhat less-good mechanical properties.
Basolateral sorting of LDL receptor in MDCK cells: the cytoplasmic domain contains two tyrosine-dependent targeting determinants.

Summary In MDCK cells, transport of membrane proteins to the basolateral plasma membrane has been shown to require a distinct cytoplasmic domain determinant. Although the determinant is often related to signals used for localization in clathrin-coated pits, inactivation of the coated pit domain in the human LDL receptor did not affect basolateral targeting. By expressing mutant and chimeric LDL receptors, we have now identified two independently acting signals that are individually sufficient for basolateral targeting. The two determinants mediate basolateral sorting with different efficiencies, but both contain tyrosine residues critical for activity. The first determinant was colinear with, but distinct from, the coated pit domain of the receptor. The second was found in the C-terminal region of the cytoplasmic domain of the receptor and, although tyrosine-dependent, did not mediate endocytosis. The results suggest that membrane proteins can have functionally redundant signals for basolateral transport and that a tyrosine-containing motif may be a common feature of multiple intracellular sorting events.
Politics, Performativity, Autopoiesis: Toward a Discourse Systems Theory of Political Culture

As a field of critical inquiry, cultural studies has engaged with the political primarily at the level of cultural politics—the politics of culture—and has all too often neglected political culture—the culture of politics. Although the emergence of cultural policy studies since the late 1980s has remedied this deficiency to some degree, cultural studies approaches politics and governmental policy primarily insofar as they impinge on a cultural domain bounded by the aesthetic and the intellectual. This essay addresses this lacuna in the cultural studies gaze by elaborating a discourse systems theory of political culture based on Michel Foucault's theory of discourse in The Archaeology of Knowledge, speech act theory, and autopoietic systems theory. The essay argues that political culture is an autopoietic, performative discourse system that regulates the production of political knowledge and the performance of political action.
Getting a life: homo ludens as postmodern identity.

Abstract The traditional markers of social identity -particularly occupation -lose much of their potency in postmodern times, which are characterized by diversity, fragmentation, discontinuity, and paradox. Many people in the industrialized West have benefited from technology, yet their jobs and day-to-day lives have been reduced to sedentary, boring routines, largely devoid of excitement, challenge, and personal growth. In consequence, they are beginning to replace homo faberwith homo ludensas the characterization from which to draw their social identities and self-enhancement needs, an inflection which has significant consequences for the leisure and tourism industry.
Multiple independent inputs are required for activation of the p70 S6 kinase

Previous studies have shown that the noncatalytic carboxy-terminal tail of the p70 S6 kinase (amino acids 422 to 525) contains an autoinhibitory pseudosubstrate domain that is phosphorylated in situ during activation and in vitro by mitogen-activated protein kinases. The present study shows that a recombinant p70 deleted of the carboxy-terminal tail (p70 delta CT104) nevertheless exhibits a basal and serum-stimulated 40S kinase activity and susceptibility to inhibition by wortmannin very similar to those of the parent, full-length p70 kinase. Carboxy-terminal deletion reduces the extent of maximal inhibition produced by rapamycin, from > 95% in the full-length p70 to 60 to 80% in p70 delta CT104, without altering the sensitivity to rapamycin inhibition (50% inhibitory concentration of 2 nM). Serum activation of p70 delta CT104, as with the parent, full-length p70, is accompanied by an increase in 32P content (about twofold) in situ and a slowing in electrophoretic mobility; both modifications are inhibited by pretreatment with wortmannin or rapamycin. 32P-peptide maps of p70 delta CT104 show multisite phosphorylation, and wortmannin and rapamycin appear to cause preferential dephosphorylation of the same subset of sites. Thus, it is likely that activation of the kinase requires phosphorylation of p70 at sites in addition to those previously identified in the carboxy-terminal tail. Evidence that the carboxy-terminal tail actually functions as a potent intramolecular inhibitor of kinase activity in situ is uncovered by deletion of a short acidic segment (amino acids 29 to 46) from the p70 amino-terminal noncatalytic region. Deletion of amino acids 29 to 46 causes a >95% inhibition of p70 activity despite continue phosphorylation of the carboxy-terminal tail in situ; additional deletion of the carboxy-terminal tail (yielding p70 delta 29-46/ delta CT104) increases activity 10-fold, to a level approaching that of p70 delta CT104. Deletion of residues 29 to 46 also abolishes completely the sensitivity of p70 to inhibition by rapamycin but does not alter the susceptibility to activation by serum of inhibition by wortmannin. Although the mechanisms underlying the effects of the delta 29-46 deletion are not known, they are not attributable to loss of the major in situ p70 phosphorylation site at Ser-40. Thus, activation of the p70 S6 kinase involves multiple, independent inputs directed at different domains of the p70 polypeptide. Disinhibition from the carboxy-terminal tail requires, in addition to its multisite phosphorylation, an activating input dependent on the presence of amino acids 29 to 46; this p70-activating input may be the same as that inhibited by rapamycin but is distinct from that arising from the wortmannin-inhibitable phosphatidylinositol 3-kinase. In addition, as exemplified by the rapamycin-resistant but mitogen- and wortmannin-sensitive p70 delta 29-46/ delta CT104 mutant, a further activating input, which probably involves site-specific phosphorylation in the segment between amino acids 46 to 421, is necessary.
Ideal Femoral Head Size in Total Hip Arthroplasty Balances Stability and Volumetric Wear

Background Over the last several years, a trend towards increasing femoral head size in total hip arthroplasty to improve stability and impingement free range of motion has been observed.
Lifetime prediction of fluorescent lamps used in photovoltaic systems

This paper approaches lifetime prediction of fluorescent lamps in photovoltaic systems by means of an analytical model. This can assist in improving ballast design and extending the lifetime of fluorescent lamps. As a result of our work, the temporal integral of the glow current to starting and the lamp voltage during normal operation normalised to nominal voltage appear to be the two independent variables that describe the influence of startup and continuous operation on lamp lifetime with an acceptable degree of accuracy. The analytical expression found explains 92.4% of the variability in lifetime. Model agreement with original data and its range of application and limitations are also analysed.
Current status and trends in shovelnose sturgeon (Scaphirhynchus platorynchus) management and conservation

Summary The objective of this study was to update information regarding the status of shovelnose sturgeon fisheries. Although a substantial amount of shovelnose sturgeon research has been conducted in the past decade, the study purpose was not to provide a comprehensive review of the literature; the primary interest was in the status, trends, and management of Scaphirhynchus platorynchus fisheries in North America. Biologists were surveyed in all 24 states within the native distribution of the species; results indicate that commercial harvest is currently permitted in eight states, recreational harvest is allowed in 13 states, and that regulations vary within rivers and jurisdictional boundaries. Although recreational exploitation of shovelnose sturgeon is thought to be low and not a significant threat to populations, commercial harvest is a major concern in states with a commercial fishery. In the last decade harvest has increased in all states with commercial shovelnose sturgeon fisheries, but recent implementation of regulations has decreased harvest in some states. Approximately half of the states with extant shovelnose sturgeon populations conduct routine monitoring of the species, and the understanding of shovelnose sturgeon populations is increasing.
Minimally invasive valve surgery with antegrade perfusion strategy is not associated with increased neurologic complications.

Background A Society of Thoracic Surgeons' publication recently associated "minimally invasive" approaches with increased neurologic complications; this proposed association was questionable due to imprecise definitions. To critically reevaluate this issue, we reviewed a large minimally invasive valve experience with robust definitions. Methods From November 1995 to January 2007, 3,180 isolated, non-reoperative valve operations were performed; 1,452 (45.7%) were aortic replacements and 1,728 (54.3%) were mitral valve procedures. Surgical approach was standard sternotomy (28%) or minimally invasive technique (72%). Antegrade arterial perfusion was used in 2,646 (83.2%) patients and retrograde perfusion in 534 (16.8%). Aortic clamping was direct in 83.4%, with endoclamp in 16.4% and no clamp in 0.2%. Patients were prospectively followed in a proprietary database and the New York State Cardiac Surgery Reporting System (mandatory, government audited). A neurologic event was defined as a permanent deficit, a transient deficit greater than 24 hours, or a new lesion on cerebral imaging. Results Hospital mortality for aortic valve replacement was 4.0% (sternotomy [5.1%] versus minimally invasive [3.4%] p = 0.13); for mitral procedures it was 2.4% (sternotomy [4.8%] versus minimally invasive [1.8%] p = 0.001). Multivariate analysis revealed that age, female gender, renal disease, ejection fraction less than 0.30, chronic obstructive pulmonary disease, and emergent operation were risk factors for mortality. Stroke occurred in 71 patients (2.2%) (sternotomy [2.1%] versus minimally invasive [2.3%] p = 0.82). Multivariate analysis of neurologic events revealed that cerebrovascular disease, emergency procedure, no-clamp, and retrograde perfusion were risk factors. In patients 50 years old or younger (n = 662), retrograde perfusion had no significant impact on neurologic events (1.6% vs 1.1%, p = 0.57). Conclusions A minimally invasive approach with antegrade perfusion does not result in increased neurologic complications. Retrograde perfusion, however, is associated with increased neurologic risk in older patients.
A new instructional environment for beginning computer science students

At the Computer Science Conference in St. Louis in February, 1981, there were 34 job offers for each PhD and 12 for each Bachelors candidate.These figures come as no surprise to those of us who teach undergraduate computer science courses. Where we once taught beginning classes of 30, we are performing before lecture sections of 250.This short paper reports on an innovative introductory computer science course which attempts to make more productive use of faculty and teaching assistant time.
A Compositional Rule for Hardware Design Refinement

We present an approach to designing verified digital systems by a sequence of small local refinements. Refinements in this approach are not limited to a library of predefined transformations for which theorems have been previously established. Rather, the approach relies on localizing the refinement steps in such a way that they can be verified efficiently by model checking. Toward this end, a compositional rule is proposed by which each design refinement may be verified independently, in an abstract environment. This rule supports the use of downward refinement maps, which translate abstract behavior detailed behavior. These maps may involve temporal transformations, including delay. The approach is supported by a verification tool based on symbolic model checking.
Recent advancements in buff and draft testing techniques

A new method for evaluating the curving stability of any freight railway car under buff and draft conditions is described. A special test vehicle was designed and constructed by the Association of American Railroads (AAR) for the purpose of applying controlled levels of lateral load at the coupler pin of any adjacent car and while in motion. This test vehicle is used in determining the maximum lateral coupler load that can be safely applied to any candidate car under various curving and speed conditions. Analytical methods are also developed for predicting the coupler angles and forces generated under any given buff or draft conditions, track curvature, and coupling arrangements. The proposed method combines testing with analysis in order to determine the level of buff or draft force at which the lateral coupler load test limits are exceeded. As an example for the method, the developed techniques are used to examine the curving performance of a standard 89-ft flatcar when coupled to another relatively short 2-axle flatcar. The results indicate that the coupling of the two cars reduces the curving stability of the long flatcar under realizable buff and draft conditions. >
Statistical analyses of temporal information in auditory brainstem responses to tones in noise: correlation index and spike-distance metric.

Gai and Carney (J Neurophysiol 96:2451–2464, 2006) previously explored the detection of tones in noise based on responses in the anteroventral cochlear nucleus; that study focused on temporal information in discharge reliability and analyses of neural responses related to the fine structure or envelope of the stimulus. Two additional temporal approaches, the correlation index (Joris et al., Hearing Res 216–217:19–30, 2006) and the spike-distance metric (Victor and Purpura, J Neurophysiol 76:1310–1326, 1996; Netw Comput Neural Syst 8:127–164, 1997), are tested in the present study. Trends in the correlation index as a function of stimulus level are similar to those of the synchronization coefficient (also called the vector strength) when the tone is presented alone. However, the present study found that trends in the correlation index did not agree with those of the synchronization coefficient for tones presented with relatively high-level background noise. Instead, trends in the correlation index generally agreed with those of the temporal reliability metric discussed in Gai and Carney (J Neurophysiol 96:2451–2464, 2006); that is, the correlation index decreased with increased tone level in the presence of relatively high-level background noise. The spike-distance metric, which was based on absolute spike times or on interspike intervals, was compared to the temporal measures described above, which were generally based on relative spike times. The results confirm that the spike-distance metric is not an optimal temporal metric. In addition, absolute spike times of primary-like responses generally contained much less temporal information than absolute spike times of chopper response types. The present study highlights the importance of relative spike-timing information as characterized by traditional and novel temporal measures.
Phase Separation in Borosilicate Glasses as Seen by Electron Microscopy and Scanning Electron Microscopy

Microstructures of two sodium borosilicate glasses were examined. Electron micrographs of replicas of water-etched fracture surfaces show that the microphases increase in size with the temperature and time of heat treatment. The relative amounts of soluble and insoluble microphases remain essentially unchanged. Scanning electron micrographs of completely leached glasses show that the insoluble phase is randomly interconnected. Scanning electron micrographs of colloidal deposits in the pores of the leached glass, which result from acid leaching of the heat-treated base glass, are shown. Electron micrographs showing re-solution of the phases are also included.
Statistical iterative scheme for estimating atmospheric relative humidity profiles

Estimation of atmospheric relative humidity profiles using passive remote sensing techniques is difficult when the temperature profile is not well known, and such retrievals approach singularity when the atmosphere is nearly isothermal. A retrieval method that is more robust near isothermal regions and temperature inversions is described. Its robust character results from an iterative combination of statistical methods based on a priori data, which stabilize the effects of any singularities, and physical methods that reflect the nonlinear character of the equation of radiative transfer and the dependence of measurements on uncertain surface reflectivities and temperature profiles. This method can be used to interpret data from meteorological satellites. It was tested extensively using simulated clear-sky microwave observations from space at 89 GHz, 166 GHz, and three frequencies near the 183-GHz water vapor resonance and the 60-GHz oxygen band, which is sensitive to the atmospheric temperature profile. Humidity profiles from the tropical, midlatitude, and arctic regions were retrieved. Relative humidity profiles retrieved using the statistical iterative method typically had errors between 5 and 10% in the 300-1000 mbar pressure region. These errors were somewhat less in the tropics and greater in the polar regions, and represented significantly better performances than a linear statistical retrieval method. >
Armodafinil in the treatment of excessive sleepiness.

Importance of the field: Excessive sleepiness causes impaired quality of life and increases the risk of poor health and accidents. Armodafinil is a wake-promoting agent approved in 2007 by the US Food and Drug Administration for the treatment of excessive sleepiness arising from narcolepsy, obstructive sleep apnea (OSA; even after optimal treatment for the underlying obstruction) and shift-work disorder (SWD). It is the R-enantiomer of modafinil, which is a racemic mixture of R- and S-enantiomers.Areas covered in this review: This review summarizes the recent primary data on the pharmacokinetics, clinical efficacy and safety of armodafinil using literature published since 2005 that was identified from PubMed.What the reader will gain: The review describes recent advances in the understanding of the pharmacokinetic profile of the drug and why this may improve wakefulness later after dosing compared with modafinil. It also describes the recent efficacy and safety data supporting the use of armodafinil to tr...
Perspectives of delegation in team-based distributed software development over the GENI infrastructure (NIER track)

Team-based distributed software development (TBDSD) is one of the single biggest challenges facing software companies. The need to manage development efforts and resources in different locations increase the complexity and cost of modern day software development. Current software development environments do not provide suitable support to delegate task among teams with appropriate directives. TBDSD is also limited to the current internet capabilities. One of the resulting problems is the difficulty to delegate and control tasks assigned among remote teams. This paper proposes (1) a new framework for delegation in TBDSD, and (2) perspectives for deploying Process-centered Software Engineering Environments (PSEE) over the Global Environment for Network Innovations (GENI) infrastructure. GENI, the 'future Internet' that is taking shape in prototypes across the US, will allow, in the context of our study, to securely access and share software artifacts, resources, and tools as never before seen over the current Internet.
Microstimulation in visual area MT: effects on direction discrimination performance

Physiological and behavioral evidence suggests that the activity of direction selective neurons in visual cortex underlies the perception of moving visual stimuli. We tested this hypothesis by measuring the effects of cortical microstimulation on perceptual judgements of motion direction. To accomplish this, rhesus monkeys were trained to discriminate the direction of motion in a near-threshold, stochastic motion display. For each experiment, we positioned a microelectrode in the middle of a cluster of neurons that shared a common preferred direction of motion. The psychophysical task was then adjusted so that the visual display was presented directly over the neurons’ receptive field. The monkeys were required to discriminate between motion shown either in the direction preferred by the neurons or in the opposite direction. On half the trials of an experiment, we applied electrical microstimulation while monkeys viewed the motion display. We hypothesized that enhancing the neurons’ discharge rate would introduce a directionally specific signal into the cortex and thereby influence the monkeys’ choices on the discrimination task. We compared the monkeys’ performance on “stimulated” and “nonstimulated” trials in 139 experiments; all trials within an experiment were presented in random order. Statistically significant effects of microstimulation were obtained in 89 experiments. In 88 of the 89 experiments with significant effects (97%), the monkeys indicated that motion was in the neurons’ preferred direction more frequently on stimulated trials than on nonstimulated trials. The data demonstrate a functional link between the activity of direction selective neurons and perceptual judgements of motion direction.
Mobile-IP, ad-hoc networking, and nomadicity

Continuing advances in wireless communications and feature integration into laptop computers are creating the need to allow nomadic users to make network connections to the Internet and with each other with no loss of functionality. This requires new advances in routing protocols and application interfaces. We use Mobile-IP as the basis for providing mobility for nomadic users, and extend it to facilitate additional services for nomadic users both at the network layer and above. As an example of how Mobile-IP can be useful with other protocols at the network layer, we show how Mobile-IP can naturally extend the usefulness of ad-hoc networking. For higher level protocols, we show that, by offering a callback service, Mobile-IP can enable applications to be responsive to changing network conditions. As an example of this technique, we show how service location can benefit from interaction with Mobile-IP. We also mention some other nomadic services which will similarly benefit from a callback service from Mobile-IP.
Pravastatin Improves Function in Hibernating Myocardium by Mobilizing CD133+ and cKit+ Bone Marrow Progenitor Cells and Promoting Myocytes to Reenter the Growth Phase of the Cardiac Cell Cycle

3-hydroxy-3-methyl glutaryl coenzyme A reductase inhibitors have been reported to increase circulating bone marrow progenitor cells and variably improve global function in heart failure. The potential role of improved perfusion versus direct effects of statins on cardiac myocytes has not been established. We chronically instrumented swine with a left anterior descending artery (LAD) stenosis to produce chronic hibernating myocardium with regional contractile dysfunction in the absence of heart failure. Hemodynamics, function, perfusion, and histopathology were assessed in pigs treated for 5 weeks with pravastatin (n=12) versus untreated controls (n=10). Regional LAD wall thickening was depressed under baseline conditions (LAD 3.7+/-0.3 versus 6.6+/-0.3 in remote regions, P<0.01). It remained unchanged in untreated animals but increased from 3.8+/-0.6 to 5.2+/-0.5 mm after pravastatin (P<0.01). There was no increase in myocardial perfusion at rest or during vasodilation. Pravastatin mobilized circulating CD133(+)/cKit(+) bone marrow progenitor cells and increased myocardial tissue levels (LAD CD133(+) cells from 140+/-33 to 884+/-167 cells/10(6) myocyte nuclei and cKit(+) cells from 223+/-49 to 953+/-123 cells/10(6) myocyte nuclei). Pravastatin increased myocytes in mitosis (phospho-histone-H3; 9+/-5 to 43+/-7 nuclei/10(6) myocyte nuclei, P<0.05) and the growth phase of the cell cycle (Ki67; 410+/-82 to 1261+/-235 nuclei/10(6) myocyte nuclei, P<0.05) in diseased but not normal hearts. As a result, pravastatin increased LAD myocyte nuclear density from 830+/-41 to 1027+/-55 nuclei/mm(2) (P<0.05). These data indicate that, in the absence of impaired endothelial function and heart failure, dysfunctional hibernating myocardium improves after pravastatin. This effect is independent of myocardial perfusion and related to mobilization of CD133(+)/cKit(+) bone marrow progenitor cells which stimulate myocyte proliferation resulting in quantitative increases in myocyte nuclear density.
Biology and pathology of Ribes and their implications for management of white pine blister rust

Summary Ribes (currants and gooseberries) are telial hosts for the introduced and invasive white pine blister rust fungus, Cronartium ribicola. Knowledge of wild and introduced Ribes helps us understand the epidemiology of blister rust on its aecial hosts, white pines, and develop disease control and management strategies. Ribes differ by species in their contribution to initial establishment and subsequent intensification of blister rust. Their significance to pine infection depends on their inherent capacities to become infected and support spore production, their abundance and environmental interactions. Ribes and white pines are adapted to disturbance and frequently co-occur in forest and woodland ecosystems. Differences in light and moisture requirements affect how long various species of Ribes occupy a site. Natural or artificial selection increases rust resistance in white pines, Ribes, and other host genera; but selection also affects virulence and aggressiveness of C. ribicola. Blister rust pathosystems evolve. Local pathosystems wherein the rust and its hosts coexist with reduced damage could arise by several processes.
Long-term functional outcome of tibial plateau leveling osteotomy versus extracapsular repair in a heterogeneous population of dogs.

Objective To compare the long-term outcome of tibial plateau leveling osteotomy (TPLO) and extracapsular repair (ECR) for treatment of a ruptured cranial cruciate ligament (RCCL). Study Design Prospective clinical trial. Animals Normal adult dogs (control, n = 79); dogs with unilateral CCL disease (n = 38). Methods Dogs had TPLO (n = 15) or ECR (n = 23) for treatment of RCCL. Force plate gait analysis was performed for the control group at one time point and for treatment groups at serial points: preoperatively, 2 weeks, 8 weeks, 6 and 12 months postoperatively. Symmetry indices (SIs) were calculated between operated and unoperated pelvic limb for ground reaction forces (GRFs), including peak vertical force (PVF), contact time (CT), and vertical impulse (VI). GRFs of the treatment groups and control group were compared using a general linear model and Kaplan–Meier survival analysis. Results At 8 weeks, for PVF and VI, the TPLO group had more symmetric limb loading than the ECR group at the walk and trot. SIs of the TPLO group were not different from the control group by 6 months to 1 year postoperatively. SIs for the ECR group were less symmetrical than the control group at all time periods. Using survival analysis, median time to normal function was no different at the walk between groups, but was shorter for the TPLO group for VI and PVF. Conclusions Dogs achieved normal limb loading faster after TPLO than ECR. TPLO resulted in operated limb function that was indistinguishable from the control population by 1 year postoperatively.
Stock exchange seats as capital assets

Abstract Stock exchange seats are important assets for securities brokers since they provide access to centralized secondary trading markets for corporate securities at a reduced cost. This paper provides empirical evidence on the dynamic behavior of monthly New York and American Stock Exchange seat prices over the 1926–1972 period. Specifically, evidence is presented which: (a) is consistent with a multiplicative random walk model for seat prices; (b) indicates that unexpected changes in the prices of exchange-listed stocks or in the volume of shares traded on the exchange are important new information about the value of seats in each month; and (c) indicates that the market for seats is efficient in assimilating new information and quickly incorporates new information into the prices of seats. In addition, we examine the effect of the infrequent trading of seats on the statistical properties of the models.
Accurate Inter-Transaction Dependency Tracking for Repairable DBMS

A reparable database management system has the ability to automatically undo the set of transactions that are corrupted by a human error or malicious attack. The key technical challenge to building repairable database management systems is how to accurately and efficiently keep track of inter-transaction dependencies that take place through a database as well as through application logic. In this paper, we present the design, implementation and evaluation of the inter-transaction dependency tracking mechanisms used in a repairable database management system called RDB2, which adds fast repairability in a portable way to a commercial DBMS Oracle 9.2.0. RDB2 eliminates dependencies due to false sharing using fine-grained inter-transaction dependency tracking, and is able to successfully identify a major source of false negatives, phantom dependencies. With these advanced inter-transaction dependency tracking mechanisms, RDB2 can significantly improve the availability of modern DBMSs by facilitating and sometimes even automating the damage repair process after an error or attack. Performance measurements on the fully operational prototypes under the TPC-C benchmark show that the run-time throughput penalty of these enhanced inter-transaction dependency tracking mechanisms is less than 18%.
Sexual reproduction reshapes the genetic architecture of digital organisms

Modularity and epistasis, as well as other aspects of genetic architecture, have emerged as central themes in evolutionary biology. Theory suggests that modularity promotes evolvability, and that aggravating (synergistic) epistasis among deleterious mutations facilitates the evolution of sex. Here, by contrast, we investigate the evolution of different genetic architectures using digital organisms, which are computer programs that self-replicate, mutate, compete and evolve. Specifically, we investigate how genetic architecture is shaped by reproductive mode. We allowed 200 populations of digital organisms to evolve for over 10 000 generations while reproducing either asexually or sexually. For 10 randomly chosen organisms from each population, we constructed and analysed all possible single mutants as well as one million mutants at each mutational distance from 2 to 10. The genomes of sexual organisms were more modular than asexual ones; sites encoding different functional traits had less overlap and sites encoding a particular trait were more tightly clustered. Net directional epistasis was alleviating (antagonistic) in both groups, although the overall strength of this epistasis was weaker in sexual than in asexual organisms. Our results show that sexual reproduction profoundly influences the evolution of the genetic architecture.
Modeling the two-dimensional emitter-base and base-collector juction capacitances of bipolar junction transistors

Structure ideale d'un support de transistor bipolaire v/p/n. Developpement d'un circuit equivalent representant les tensions de polarisation, les elements resistifs et capacitifs du modele a deux dimensions du transistor. Calcul a partir du circuit equivalent des tensions, des impedances des deux jonctions. Modele analytique a deux dimensions, des capacitances des jonctions emetteur-base et base-collecteur du transistor bipolaire. Illustrations et conclusions
Continuing Education for Health Professionals

Although continuing education in the health professions is an important endeavor, it has been largely neglected in the professional literature. Few studies have been done on (a) conceptual models to guide the design and implementation of continuing education and (b) the use of such models in continuing education. To fill this gap, two such models are described in this article: (a) instructional development and (b) community development. Combining and using these models can lead to more effective continuing education with more enduring effects. Principles to guide the implementation of these models are presented. An arthritis continuing education project based on the instructional and community development models is used to illustrate these principles. This continuing education project focused on occupational and physical therapists in clinical practice.
Portfolio Selection Using Stochastic Dominance Criteria

The direct application of stochastic dominance criteria to portfolio selection problems has been thought impractical because an extremely large number of combinations of returns must be considered. This paper proposes and evaluates a rigorous statistical procedure for sampling the combinations of returns on candidate risky assets so that stochastic dominance criteria may be used directly in an efficient linear programming model for portfolio selection. The sampling scheme exploits the association of the return on each candidate stock with the return on a market index in a manner analogous to the Sharpe single-index model, thereby eliminating the large number of combinations with probabilities close to or equalling zero. Portfolios computed by the proposed linear programming stochastic dominance model are compared with those computed by the single-index quadratic programming model, using 180 months of recent data on a sample of NYSE common stocks.
Capillary dynamics of coupled spherical-cap droplets

Centre-of-mass motions of two coupled spherical-cap droplets are considered. A model with surface tension and inertia that accounts for finite-amplitude deformations is derived in closed form. Total droplet volume A and half-length L of the tube that connects the droplets are the control parameters. The model dynamics reside in the phase-plane. For lens-like droplets λ 1, the symmetric state loses stability (saddle point) and new antisymmetric steady states arise about which limit-cycle oscillations occur. These mirror states - big-droplet up or big-droplet down - are also stable. In addition, there are large finite-amplitude 'looping' oscillations corresponding to limit cycles that enclose both steady states in the phase-plane. All three kinds of oscillations are documented in an experiment that sets the system into motion by 'kicking' one of the droplets with a prescribed pressure-pulse. Model predictions for frequencies are consistent with observations. Small-amplitude predictions are placed in the wider context of constrained Rayleigh vibrations. A model extension to account for the small but non-negligible influence of viscosity is also presented.
Interactions of rooftop PV deployment with the capacity expansion of the bulk power system

Abstract Distribution-sited solar photovoltaics (PV) economics (including rooftop PV) have improved significantly during the past several years, spurring increased installations, with over 2.2 GW installed in 2014 in the United States. This increased deployment is largely projected to continue and has prompted additional interest in the interactions of rooftop PV deployment with the greater electricity system. In this paper we focus on one piece of this interface, namely the interaction between rooftop PV deployment and the evolution of the bulk power system. We develop a novel linkage between NREL’s bulk power capacity expansion model (the Renewable Energy Deployment System [ReEDS] model) and NREL’s rooftop PV adoption model (the dSolar model). We use these linked models to gain insights into the interactions of rooftop PV deployment with the bulk power system. We explore two sets of scenarios. In the first set we examine how different levels of rooftop PV deployment impact the generation mix on the bulk power system. In the second set we examine how the generation mix of the bulk power system impacts the deployment of rooftop PV by applying grid-wide curtailment rates to rooftop PV systems. In these sets of scenarios, we find that rooftop PV generation and utility PV generation have a nearly 1:1 substitution effect. We also find that curtailment rate feedback can have dramatic impacts on rooftop PV adoption, though the range of impacts is strongly dependent on the generation mix of the bulk power system and the amount of total PV generation in the system. For example, scenarios with more natural gas generation tended to have lower curtailment rates and thus more rooftop PV deployment.
Structure and properties of carbon nanotube-polymer fibers using melt spinning

Publisher Summary The fabrication of advanced fibers for protective applications continues to be of utmost interest. This chapter discusses the mechanical and morphological properties of polymer/carbon nanotubes composites via melt processing. It discusses the melt processing optimization for improved nanotube dispersion; the effect of fiber draw ratio on morphology and mechanical properties; the effect of nanotube type and geometry on morphology and mechanical properties; and the details on future trends for the technology and potential applications. Carbon nanotubes are graphitic sheets rolled into seamless tubes and have diameters ranging from about a nanometer to tens of nanometers with lengths up to centimeters. Although carbon nanotubes show exceptional properties on the nanoscale, the difficulty lies in creating a material that exhibits carbon nanotube properties on the macro-scale. Incorporating the nanotubes as filler into polymer matrices is the most common method currently explored. Polypropylene (PP) has been a common matrix used for carbon nanotube composites.