cssi/SciSciGPT-SciSciNet huggingface dataset:
A computational approach to designing ductile Nb-Ti-Cr-Al solid-solution alloys

This article describes a new computation-based approach for designing ductile Nb-Ti-Cr-Al solid-solution alloys. The proposed approach is based on computation of the surface energy and the Peierls-Nabarro (P-N) barrier energy as a function of alloy composition. The surface energy is used as a measure of the resistance to cleavage fracture, while the P-N barrier energy is used as a measure of dislocation mobility. The ratio of the surface energy to the P-N barrier energy is utilized as a material index which can be adjusted by alloying additions. Analytical relations are developed for computing (1) the elastic constants in terms of the d+s electrons per atom in the alloys and (2) the lattice parameter, surface energy, and P-N barrier energy in terms of alloy composition. Design of a ductile solid-solution alloy is achieved by manipulating the number of d+s electrons, through alloying additions, to obtain a high value of the ratio of the surface energy to P-N barrier energy by reducing the misfit energy of the dislocation core. Applications of the methodology to designing binary, ternary, and quaternary Nb-based solid-solution alloys with Ti, Cr, and Al alloying additions are illustrated with promising results, demonstrating that the proposed methodology is a viable approach for alloy design.
Differentiation of olfactory receptor cells in organ culture.

Presumptive olfactory mucosa was excised from the heads of rat fetuses in the eleventh and twelfth days of gestation and explanted in organ cultures. At the time of explantation, the presumptive olfactory cells were recognizable by their long narrow apical processes and basally located nuclei. However at this stage they were in an early phase of differentiation as indicated by the large numbers of free ribosomes and virtual absence of microtubules and cilia in the apical cytoplasm. After three to eight days in culture, there was a progressive increase in the total number of cells in the epithelium. Differentiation in olfactory receptor cells was detectable by the appearance in the apical processes of axially oriented microtubules and centrioles or basal bodies. Some of which generated cilia. At their basal ends, the cytoplasm narrowed into axons and bundles of these axons, arranged in the unique manner of olfactory nerve axons, entered the connective tissue. Olfactory receptor cells, as defined by morphological criteria, differentiated under suitable organ culture conditions in the absence of any tissue from the central nervous system.
Three-channel low-frequency fiber-optic voltage sensor.

We demonstrate a frequency-multiplexed three-channel fiber-optic interferometric dc and low-frequency voltage sensor based on the electrostrictive effect in lead magnesium niobate transducers. The sensor relies on the nonlinear transduction mechanism in electrostrictive materials for frequency-division multiplexing by use of a single interferometer and a single unmodulated laser. To our knowledge this is the first direct measurement of three low-frequency voltage signals with a single fiber-optic interferometer. Demonstrated cross talk between channels is less than −75 dB. The cross talk is shown to be caused by the nonlinear output of the interferometer at large applied strains.
Changes in long-term economic trends: Before and after the 1930s☆

Abstract This article uses the transfer function technique to estimate and compare trends of five major macroeconomic time series over the time periods 1902–1931 and 1937–1985. We show that the transfer function is ideally suited for this purpose since it simultaneously captures several factors which independently generate a tendency for a shock to persist over time. Transfer function estimates and simulations of inflation, nominal and real interest rates, output, and unemployment suggest that trend behavior is markedly different after the mid-1930s than before. In the latter period, we find more pronounced positive trend behavior of nominal variables and a less persistent growth rate of output.
Swiss Security Return Performance and the Investment Horizon

Investors often hold foreign securities in order to diversify their portfolios. This raises the issue of whether there are unique risks associated with long-term investments in non-domestic securities. The authors investigate the empirical relationship between the Sharpe ratio and the investment horizon for portfolios of Swiss stocks and bonds and then compare these results to U.S. stock and bond portfolios. Sharpe ratios are calculated for holding periods of one to 25 years under the contrasting assumptions that returns are independent or auto-correlated. The results for Swiss securities are very similar to those for U.S. securities. Under independent returns, bonds outperform stocks for longer time horizons, while for auto-correlated returns, equities outperform bonds for all holding periods.
Macroeconomic Crises, Policies, and Growth in Brazil, 1964-90

This study examines Brazil's economic history from the change in regime in 1964, when a populist and constitutional but economically incompetent government was overthrown by the military, to 1992, when Brazil's first popularly elected president in more than a quarter of a century was forced from office for corruption. Brazil's economic prospects for some time to come will be a legacy of this period, which witnessed not only unprecedented growth, but levels of inflation and external debt that would have been unimaginable in earlier decades.
Impaired specific CD8 T cell response with aging is not due to decreased expression of CD90 on TCR transgenic T cells

Background CD90 (Thy-1) is a small glycoprotein that is particularly abundant on the surface of mouse thymocytes and peripheral T cells, and is often used as a marker in adoptive transfer experiments to distinguish donor and recipient T cells with different CD90 subtypes. We have performed adoptive transfer experiments with T cell receptor transgenic (TCR Tg) mice to study the impaired CD8 T cell response with aging.
3D multifocus astigmatism and compressed sensing (3D MACS) based superresolution reconstruction.

Single molecule based superresolution techniques (STORM/PALM) achieve nanometer spatial resolution by integrating the temporal information of the switching dynamics of fluorophores (emitters). When emitter density is low for each frame, they are located to the nanometer resolution. However, when the emitter density rises, causing significant overlapping, it becomes increasingly difficult to accurately locate individual emitters. This is particularly apparent in three dimensional (3D) localization because of the large effective volume of the 3D point spread function (PSF). The inability to precisely locate the emitters at a high density causes poor temporal resolution of localization-based superresolution technique and significantly limits its application in 3D live cell imaging. To address this problem, we developed a 3D high-density superresolution imaging platform that allows us to precisely locate the positions of emitters, even when they are significantly overlapped in three dimensional space. Our platform involves a multi-focus system in combination with astigmatic optics and an l1-Homotopy optimization procedure. To reduce the intrinsic bias introduced by the discrete formulation of compressed sensing, we introduced a debiasing step followed by a 3D weighted centroid procedure, which not only increases the localization accuracy, but also increases the computation speed of image reconstruction. We implemented our algorithms on a graphic processing unit (GPU), which speeds up processing 10 times compared with central processing unit (CPU) implementation. We tested our method with both simulated data and experimental data of fluorescently labeled microtubules and were able to reconstruct a 3D microtubule image with 1000 frames (512×512) acquired within 20 seconds.
Observation of Nonclassical Radial Current Diffusion in a Fully Bootstrap Current Driven Tokamak.

Reconstruction and modeling of the plasma current profiles in a fully pressure driven tokamak have been performed in the Current Drive Experiment-Upgrade. The reconstructed experimental current profile has a significant deviation from that of the calculated neoclassical currents. Satisfactory agreement between the measured and calculated model profiles was obtained by including a helicity conserving current diffusion term in the modeling which created the required self-generated ``seed'' current.
An experimental study on the effects of oxygenated fuel blends and multiple injection strategies on DI diesel engine emissions

Abstract Experimental studies on effects of oxygenated fuels in conjunction with single and split fuel injections were conducted at high and low loads on a Caterpillar SCOTE DI diesel engine. At high loads, a significant beneficial effect of oxygenated fuels was seen to reduce soot emissions with little or no penalty on NOx emissions. Also, at high loads, split injection had an additional favorable effect on soot emissions as compared to single injections, but the soot reducing influence of the oxygenates was not as marked as that seen with the single injection cases. This result indicates that the soot reduction due to the addition of oxygenate to the fuel is most effective in rich combustion as split injections are known to be effective at leaning-out the charge. In fact, at low engine loads when the overall mixture is further leaned-out, the oxygenated fuels had only a slight effect on particulate emissions. Split injections were effective in reducing particulate emissions at low loads particularly at advanced fuel injection timings when overall temperatures would be expected to be higher.
Solubility modeling of solids in supercritical fluids using the Kirkwood-Buff fluctuation integral with the hard-sphere expansion (RISE) theory

Abstract The hard-sphere expansion (HSE) theory is incorporated in the Kirkwood-Buff fluctuation integral to predict solubilities of solids in supercritical carbon dioxide and ethylene. While an equation-of-state only for pure supercritical solvent is needed in the HSE model and, thus, there is no need to know the critical properties of solids, three adjustable parameters (two molecular size parameters α11, α12, and one dimensionless parameter α12) in the HSE model are determined to fit experimental solubility data. The results on the solubility prediction by the HSE model with the Peng-Robinson equation-of-state for pure component were better than the Peng-Robinson equation-of-state with the classical mixing rule in both cases: (1) when the molecular parameters in the HSE model and the binary interaction parameter k12 in the mixing rule were assumed to be temperature-dependent; and (2) when α12 and k12 were considered as temperature-dependent.
Agonistic stress in early adolescence and its effects on reproductive effort in young adulthood

Agonistic stress (AS) is normally associated with the suppression of fertility behavior; however, there are conditions under which the association is reversed. In this article, we investigate the effects of AS using longitudinal data from a large sample (n=9731) of young adults in the United States. We find that repeated exposure to AS is associated with early fertility, higher fertility over a 10-year period, and low investment in long-term mating relationships. The association of AS with early fertility and mating behavior is mediated by antisocial preferences. However, the positive association between AS and fertility behavior over the long run is robust with respect to the controls in the model. We believe that our findings align well with studies showing increased reproductive effort in response to agonistic interactions with conspecifics.
Monkey motor stimulation and altered social behavior during chronic methadone administration

To assess the effects of chronic methadone administration on locomotor, social, and eating behavior of drug-naive individuals under circumstances approximating those of methadone “maintenance” clinics, we gave single, daily oral doses of methadone to 5 Macaca radiata monkeys living in a social group. We obtained motor activity counts automatically during 6 weeks of baseline, 10 weeks of drug administration, and 3 weeks of post-drug abstinence. Social behaviors of association, dominance, submission, and sexuality were counted 5 days per week, and animal weights, food eaten, and food-reinforced work were recorded. Plasma methadone levels were near those achieved in methadone clinics. Methadone produced mixed stimulation and sedation in the daytime, with stimulation predominating for 4 hrs following administration. At night the subjects moved less while taking the drug. Associative behaviors were reduced by methadone, but dominance, submission, and sexual behaviors were not altered. The monkeys ate less while taking the drug, losing weight and working less for food. In these primates methadone had significant stimulant properties, impaired important social behaviors, and reduced the potency of food as a reinforcer of work. The results are compared with methadone's effects upon humans.
Merging of drops to form bamboo waves

Abstract Topological transitions in core-annular flow of oil and water are described. Drops of one liquid are suspended in the second liquid and transported through a pipeline under a pressure gradient. We examine the merging of an array of drops in this two-fluid flow. Larger drops are found to merge and the flow undergoes a topological transition to core-annular flow. In core-annular flow of two liquids, one liquid lies at the core and the other surrounds it. For the case of large oil bubbles in water, a steady core-annular flow with bamboo waves on the interface is achieved. For the case of large water bubbles in oil, the ensuing core-annular flow has continually breaking waves at the interface.
An experience report on developing an automated web services platform

Web services have attracted significant industry interest as a low-cost and flexible technology alternative to distributed object and proprietary message-oriented methods for delivery of on-demand business processes, enabling intra-organizational systems integration, and in the long term, development of dynamic inter-organizational process networks that may revolutionize B2C and B2B e-commerce. Exploiting this latent potential of web services technology requires the development of automated techniques for scalable and reliable service composition and execution in web service platforms. In this paper, we summarize our experience in developing an architectural framework for web services platforms, called Integrated Service Planning and Execution architecture (ISP & E). The use of recent advances in AI planning, learning and semantic web technologies for service composition, reliable service execution, transaction synthesis, and model-driven deployment of services is discussed. Furthermore, we discuss implications for and research issues in the development of web services based systems to aid e-business.
Monitoring pudendal nerve function during labor.

Abstract Background: To determine methodology and feasibility of pudendal nerve monitoring during labor and delivery. Methods: With Institutional Review Board approval, 13 low-risk, singleton pregnant women were recruited. The latency and amplitude of the perineal branch of the pudendal nerve compound muscle action potential were recorded during the second stage of labor and after delivery. With the first two patients, a wire electrode was used to stimulate the pudendal nerve continuously at the ischial spine. For the remaining 11 patients, a St. Mark’s electrode was used to stimulate transvaginally. A urethral ring electrode on a 14 French foley catheter monitored the response from the urethral sphincter. All patients received prophylactic antibiotics. Experience: Twelve patients delivered vaginally, and one by cesarean. In two patients, continuous wire stimulation showed a gradual decrease in amplitude. Changes were minimal over 15-minute intervals. Wire electrode placement was technically difficult and dislodged easily. With the remaining 11 patients, all had data available for interpretation, and of the 85 potential perineal branch of the pudendal nerve compound muscle action potentials, 53 were obtained. No patients developed cystitis. Conclusion: Intrapartum assessment of pudendal nerve function is feasible. Continuous wire stimulation is technically more difficult and does not provide additional information beyond that available from intermittent stimulation.
Sex characteristics, task clarity, and authority

This study was conducted to investigate the effect of sexual stereotyping on the exercise of authority. The hypotheses were that the sexual composition of the group affects the authority behavior of group leaders when the task has low clarity but that sex characteristics have no effect on authority behavior when the task has high clarity. These predictions were expected to hold both in situations where there is a direct association between sex and the task ability and in situations where no such connection is established. As predicted, no significant difference was found in the number of high control acts made by male and female leaders in the high task clarity conditions, even when sex was directly related to the task ability. Also as hypothesized, sex effects did operate strongly in the low task clarity conditions. Male leaders made significantly more high control acts than female leaders, even in conditions where no prior relation was established between sex and the task ability. Thus, these results indicate that the effect of sex characteristics on the exercise of authority is enhanced in low task clarity situations and is neutralized in high task clarity situations.
A mitochondrial pool of sphingomyelin is involved in TNFα-induced Bax translocation to mitochondria

We recently showed that targeting bSMase (bacterial sphingomyelinase) specifically to mitochondria caused accumulation of ceramide in mitochondria, and induced cytochrome c release and cell death [Birbes, El Bawab, Hannun and Obeid (2001) FASEB J., 15, 2669-2679]. In the present study, we investigated the role of this mitochondrial pool of ceramide in response to a receptor-mediated event, namely TNFalpha (tumour necrosis factor alpha), and the involvement of this mitochondrial pool of ceramide in Bax translocation to mitochondria, an event that precedes cytochrome c release. Treatment of MCF7 cells with TNFalpha caused an increase in ceramide levels in the mitochondrial fraction which accompanied Bax translocation to mitochondria. Targeting bSMase to mitochondria specifically resulted in Bax translocation to mitochondria, suggesting that the mitochondrial ceramide pool is involved in Bax translocation. Moreover, in a reconstituted cell-free system, treatment of isolated mitochondria with bSMase enhanced Bax association with mitochondrial membranes. Collectively, these results suggest that the generation of ceramide in mitochondria in response to TNFalpha is sufficient to induce Bax translocation to mitochondria and subsequent cytochrome c release and cell death.
Partisan Change and Shifting Expenditure Priorities in the American States, 1945-1978:

This article examines the impact of shifts in partisan control of the governorship and state legislatures on longitudinal patterns of expenditure priorities for 38 states from 1945 to 1978. I sugge...
Hydroelectric Generator Excitation Experience at Grand Coulee

1. Experience with the motor-driven exciter at the Grand Coulee Power Plant indicates that automatic transfer of power sources to the motor can be successfully done under full load by removing the motor from a faulty power source and reconnecting it to another power source. 2. However, experience also indicates that the best protection is to provide sufficient power sources so that the loss of one source will not cause the loss of excitation. 3. Additional pilot-exciter voltage-regulation equipment has reduced peak voltages on the generators approximately 1.5 kv on a 13.8-kv base with the possibility of reducing this still further by the addition of more resistance in the high-speed lowering relay circuit in the main exciter field.
A Case Study and Review of Pancreatitis in the AIDS Population

This case study considers a 55-year-old African American woman with the acquired immunodeficiency syndrome (AIDS) who presented with epigastric abdominal pain for 1 week. She was found to have pancreatitis on computed tomography scanning. Unique to this case are the numerous possible etiologies of her pancreatitis. Thus, this case study systematically reviews the different etiologies of pancreatitis in the AIDS population compared to the general population. Furthermore it discusses the management and treatment of pancreatitis in AIDS.
The role of molecular remodeling in differential regulation of tight junction permeability

Tight junctions create a paracellular barrier that is essential for survival of complex organisms. In many cases tight junctions define separate, generally sterile, tissue compartments. In the skin and gut, tight junctions must also seal the paracellular space to prevent microbiota from accessing the internal milieu. This is a relatively simple task in the integument, where an absolute barrier is effective. However, intestinal epithelial tight junctions are charged with the far more complex task of supporting paracellular transport of water, ions, and nutrients while providing a barrier to microbial translocation. The delicate nature of this balance, which is disrupted in disease, makes the intestine a unique organ in which to explore the complexities of tight junction permeability and barrier regulation. Here we review recent progress in understanding the molecular determinants of barrier function and events responsible for regulation, and dysregulation, of tight junction permeability.
Genetics of Coxiella burnetii

Those organisms considered to be obligate intracellular bacteria are interesting objects for genetic studies. Little is known about their mechanisms for natural genetic exchange. Many genes from the bacterium Coxiella burnetii, an obligate intraphagolysosomal pathogen, have therefore been cloned and characterized using the heterologous host Escherichia coli. Recently, use of electroporation methodology followed by long-term selection periods have provided initial data on genetic transformation in C. burnetii.
Convergence of Polynomial Restart Krylov Methods for Eigenvalue Computations

Krylov subspace methods have led to reliable and effective tools for resolving large-scale, non-Hermitian eigenvalue problems. Since practical considerations often limit the dimension of the approximating Krylov subspace, modern algorithms attempt to identify and condense significant components from the current subspace, encode them into a polynomial filter, and then restart the Krylov process with a suitably refined starting vector. In effect, polynomial filters dynamically steer low-dimensional Krylov spaces toward a desired invariant subspace through their action on the starting vector. The spectral complexity of nonnormal matrices makes convergence of these methods difficult to analyze, and these effects are further complicated by the polynomial filter process. The principal object of study in this paper is the angle an approximating Krylov subspace forms with a desired invariant subspace. Convergence analysis is posed in a geometric framework that is robust to eigenvalue ill-conditioning, yet remains relatively uncluttered. The bounds described here suggest that the sensitivity of desired eigenvalues exerts little influence on convergence, provided the associated invariant subspace is well-conditioned; ill-conditioning of unwanted eigenvalues plays an essential role. This framework also gives insight into the design of effective polynomial filters. Numerical examples illustrate the subtleties that arise when restarting non-Hermitian iterations.
Pontine atypical neurocytoma: case report.

OBJECTIVE AND IMPORTANCE: Neurocytomas are typically located within the supratentorial ventricular system. Extraventricular neurocytomas are very rare, and this is only the second reported case of a pontine neurocytoma. We discuss the clinical presentation, histology, and treatment of these rare tumors. CLINICAL PRESENTATION: A 58-year-old man presented with a 4-month history of headache and unilateral facial and distal extremity paresthesia. Magnetic resonance imaging (MRI) scans demonstrated a 2.6 x 2.2-cm ring-enhancing cystic mass in the right pons. INTERVENTION: MRI-guided stereotactic biopsy yielded a diagnosis of atypical neurocytoma. Because of the location and malignant histological features of the tumor, the patient was initially treated with external beam radiation therapy. Several months later, MRI scans demonstrated tumor progression. The patient then underwent three rounds of temozolomide chemotherapy, during and after which his symptoms worsened. Aggressive subtotal resection of the tumor was achieved via a right suboccipital craniectomy. CONCLUSION: Twenty-eight months postoperatively, the patient is symptom free, and MRI scans demonstrate no evidence of residual or recurrent tumor.
The seasonal periodicity of water molds I. Field studies

In Florida a seasonal periodicity in the occurrence of Saprolegniaceae prevails. Eccentric oospore fungi may be isolated during the entire year, but are most common in warm weather (20–30° C). Centric and subcentric oospore fungi are isolated most frequently during the months of cooler weather (2–22°C). A more representative flora will be found if water and soil collections are made during cool weather.
Improving the Performance of a Line Regulating Converter in a Converter-Dominated DC Microgrid System

This paper describes the controller design procedure for a line-regulating converter in a converter-dominated dc microgrid system. The purpose of the controller is to mitigate the effects of the constant power loads on the stability and performance of the dc microgrid system. In this work, first, the overall structure, operation, and building blocks of the dc microgrid under analysis are introduced. Next, the dynamic model of the dc microgrid and the required transfer functions for the controller design are derived. Then, two proposed controller design methods are introduced and implemented on an virtual line-regulating converter in a dc microgrid system. Finally, the controller design methods are verified experimentally using the results from a built prototype dc microgrid system.
Updates in the Management of Acute Lung Injury: A Focus on the Overlap Between AKI and ARDS

Acute respiratory distress syndrome (ARDS) is a major cause of hypoxemic respiratory failure in adults and can result from several predisposing factors, such as sepsis and trauma, which also predispose patients to acute kidney injury (AKI). Animal models of AKI and ARDS suggest that AKI increases inflammatory cytokines in the circulation such that IL-6 may be a direct mediator of AKI induced lung injury. When ARDS and AKI overlap, intensive care unit length of stay, resource utilization, and mortality increase dramatically. New evidence suggests that the prevalence and clinical implications of even mild AKI in patients with ARDS is likely underestimated. The cornerstone of therapy for ARDS continues to be low tidal volume ventilation, and more recent trials illustrate that diuretic administration to shock-free ARDS patients may help them avoid the deleterious effects of volume overload. This review focuses on new developments in the care of ARDS patients with a specific focus on interactions between the lungs and kidneys in patients with overlapping ARDS and AKI.
Illuminating aggregate heterogeneity in neurodegenerative disease.

Luminescent conjugated polymers (LCPs) bind to prion aggregates and emit different fluorescent spectra depending on their binding conformation. As such, they are promising tools for investigating the biophysical basis of prion strains.
Analytical and kinetic investigations of totally irreversible electron transfer reactions by square-wave voltammetry

Abstract The influence of slow electron transfer on the analytical performance of square-wave voltammetry is considered from an experimental viewpoint. The magnitude, shape and position of the square-wave response depends on the degree of reversibility and also the value of the transfer coefficient (α). The dimensionless square-wave peak current of 0.93 (for nE sw = 50 mV, n Δ E s = 10 mV) for a reversible system decreases to 0.39 for totally irreversible slow charge transfer when α = 1.0 and decreases monotonically to zero as α goes to zero. Although a further increase in square-wave step height has only a small effect and an increase in amplitude has a moderate effect on the square-wave response when the system is Nernstian, sensitivities can be dramatically increased, at least fivefold, with the proper choice of these parameters for irreversible systems. To illustrate these points the reduction of two compounds, N -acetylpenicillamine thionitrite (α = 0.46) and tert -butyl hydroperoxide (α = 0.08) were examined.
High Frequency Response of a Single Mode Fiber Optical Phase Modulator Utilizing a Piezoelectric Plastic Jacket

A single mode optical phase modulator utilizing a piezoelectric plastic jacket is studied theoretically. Due to the short wavelength at high frequency and the axial symmetry of the optical fiber, a radially dependent deformation is assumed. Computational results of the optical phase modulation reveal that the optimal performance may be achieved if the modulator is driven at its resonant frequencies. These resonances are caused by the thickness modes of the piezoelectric plastic jacket at lower frequencies and by the breathing modes of the glass fiber at higher frequencies. Experimental measurements (using a Mach-Zehnder interferometric configuration) up to 5 MHz on a 3 cm long sample show reasonable agreement with the theoretical predictions.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The Effect of Arousal on Warm-up Decrement

Abstract The purposes of the study were to examine whether particular strategies would enhance affective arousal and if these arousal-inducing techniques would reduce or eliminiate warm-up decrement (WUD) on the performance of a sport skill. A total of 15 female gymnasts, age 9 to 14 years, performed a series of 10 handspring vaults. After a 20-minute period which included rest and the experimental treatment, three additional trials were given. The treatments, experienced by each of the subjects, included (1) rest (REST), (2) mental practice (MP), and (3) riding a bicycle ergometer (BIKE). To ascertain arousal level, subjects completed the children's arousal scale (CAS), a 9-item semantic differential test that measured positive and negative feelings, prior to the first trial and again immediately following the experimental treatments. Heart rate also was recorded at these times to determine a physiological basis of arousal. The results indicated that the BIKE condition eliminated WUD as compared to condi...
A quasi one-dimensional method and results for steady annular/stratified shear and gravity driven condensing flows

Abstract This paper presents an effective quasi one-dimensional (1-D) computational simulation methodology for steady annular/stratified internal condensing flows of pure vapor. In-channel and in-tube flows are considered for a range of gravity component values in the direction of the flow. For these flows, three sets of results are presented and they are obtained from: (i) a full 2-D CFD based approach, (ii) the quasi-1D approach introduced here, and (iii) relevant experimental results for gravity driven condensing flows of FC-72. Besides demonstrating differences between shear and gravity driven annular flows, the paper also presents a map that distinguishes shear driven, gravity driven, and “mixed” driven flows within the non-dimensional parameter space that govern these duct flows. The paper also demonstrates that μm-scale hydraulic diameter ducts typically experience shear/pressure driven flows.
Formation kinetics of CrSi2 films on Si substrates with and without interposed Pd2Si layer

We have measured the kinetic rate of formation of CrSi2 using 2.0-MeV 4He + backscattering spectrometry. CrSi2 was formed on single-crystal 100- and 111-oriented Si and on Pd2Si grown on 100 Si. For both Si-Cr and Si-Pd2Si-Cr samples the rate of growth of CrSi2 is linear in time with an activation energy of 1.7±0.1 eV and a value of 0.7 A/sec at 450°C. For all annealing temperatures, the growth becomes nonlinear at long annealing times. The nonlinearity is attributed to a contaminant, probably oxygen. On Pd2Si, CrSi2 starts to form at about 400°C, while on Si, CrSi2 formation is observed at 450°C and above. The difference in formation temperatures is due to contamination at the Si-Cr interface, quite probably a thin oxide layer. The growth rate of CrSi2 in the Si-Pd2Si-Cr samples is independent of the thickness of Pd2Si.
Management of Unstable Angina Using Risk Stratification Methods

In the current era of health care reform, the efficacies of various management strategies are being scmtinized using measures of patient outcomes, quality of life, and costs. Acute coronary ischemic syndromes such as acute myocardial infarction (AMI) and unstable angina (UA) have received a great deal of attention because of their frequency (approximately 1,500,000 myocardial infarctions and 570,000 admissions for unstable angina annually in the US), their potential morbidity and mortality, and the costliness of newer treatment modalities. Some studies evaluating cost-effectiveness of care have suggested that many patients with suspected myocardial infarction or unstable angina can be adequately treated in a coronary stepdown or intermediate care unit at lower cost than if they are admitted to a coronary care unit. The inference is that the highest level of care is neither necessary nor cost-effective for all patients with suspected myocardialinfarction or unstable angina1-4 and better patient triage might be a reasonable cost effective strategy.
A tool for securely integrating legacy systems into a distributed environment

Legacy systems provide services that remain useful beyond the means of the technology in which they were originally implemented. Our Legacy Wrapper tool packages the services of a legacy application in order to redistribute as a distributed object. In this new environment, the wrapper provides its own layer of security between the security domain of the host and the distributed object system. This security layer includes a sandbox for the application that is designed to protect the application against malicious users and the host from malicious applications. In this paper we present the Legacy Access model and the Legacy Wrapper system. The Legacy Access model is an original system access model that presents a four tiered sandboxing model for wrapping legacy applications: complete encapsulation, shared sandbox, single sandbox, sandboxless operation. The Legacy Wrapper tool is an implementation of the model that combines wrapping an application for security purposes with wrapping it for distribution in a distributed object system.
Integrating the Freshman seminar and Freshman Problem Solving courses

The transition from high school to college can be very difficult for many students. At the University of Pittsburgh, we have a system of courses and academic counseling that is designed to address these issues and help the student in this transition. One major component is a series of mentoring courses that the entering student can select for the first semester. These courses are designed to help the freshman make this major transition. The student must also enroll in a Freshman Problem Solving course that details the use of various computer tools. This paper discusses how these courses are integrated and describes the interaction of counseling with the first semester engineering problem solving course. The paper also discusses the mentor selection process, the mentor-training program, and the topics covered in the mentoring sessions.
Endoscopically assisted balloon dacryoplasty treatment of incomplete nasolacrimal duct obstruction.

Abstract Purpose To report the success rate of endoscopically assisted balloon dacryoplasty (EADCP) for treatment of acquired incomplete nasolacrimal duct obstructions (NLDOs). Design Retrospective, noncomparative case series. Participants Records of patients treated for incomplete NLDOs with EADCP by one of the authors (WLW) were reviewed. Diagnosis of incomplete NLDO was based upon subjective complaints of tearing, dye disappearance testing, clinical evidence of epiphora, and nasolacrimal duct irrigation. Endoscopically assisted balloon dacryoplasty was performed for incomplete obstructions identified. Methods One hundred forty-two nasolacrimal systems in 103 patients with incomplete NLDOs underwent EADCP for treatment of incomplete obstructions. A 3×15-mm balloon was utilized in all procedures, with silicone lacrimal tubes placed in 131 systems. Patients received postoperative topical antibiotic–steroid drops for 2 weeks and a 1-week tapering dosage of systemic methylprednisolone. Main outcome measures Patients were assessed at their last postoperative visit by nasolacrimal system irrigation, dye disappearance testing, and subjective complaints of epiphora. Results Eighty systems (56%) experienced complete resolution of symptoms after surgery. Forty-eight additional systems (34%) showed improvement but still experienced periodic epiphora. Fourteen systems (10%) showed no improvement. The average time before follow-up was 7.5 months. Conclusion Endoscopically assisted balloon dacryoplasty as a treatment for incomplete NLDOs provides complete relief or substantial improvement in a significant percentage of patients. Nasal videoendoscopy adds significantly to the understanding of this procedure and its potential for success. Endoscopically assisted balloon dacryoplasty should be considered an appropriate treatment option for selected patients with incomplete NLDOs.
Degenerate Solutions and an Algebraic Approach to the Multiple-Input Linear Filter Design Problem

This paper describes three common types of multiple-input filter design problems; in each case Wiener's general optimum multiple-input solution is reduced to a simpler equivalent single-input solution. The first type of situation discussed is the "distortionless dual-input system." Conditions under which this additional criterion of fidelity may be advisable are discussed, two general distortionless systems are shown, and it is demonstrated that Wiener's single-input solution may be used in designing such a system. The second semigeneral solution obtained (or semispecial, as the case may be) pertains to a situation in which interference is present in one channel which is statistically similar to, but still independent of, the actual signal of interest. The third case is probably the most interesting of all in that when several signal sources are available, such as in a diversity receiving system, each corrupted by additive independent noises, the optimum system is one in which all channels are added together directly (after possible simple gain adjustments) and then passed through a single filter. It is demonstrated that this result is true even though the signal-to-noise ratios are quite different for the various input channels.
Quantifying Extreme Weather Event Impacts on the Northern Gulf Coast Using Landsat Imagery

ABSTRACT Jones, R., 2015. Quantifying extreme weather event impacts on the northern Gulf Coast using Landsat imagery. Recent high-profile hurricanes have demonstrated the destructiveness of extreme events on coastal landscapes to the world. Barrier islands across the planet are disappearing, exposing vulnerable coastal cities to the damage caused by extreme events. Growing resolve among scientists regarding climate change's connection to tropical cyclones heightens the concern around intensifying extremes and landscape dynamics. This study uses more than 600 Landsat images to examine the role of extreme events on barrier island morphology on three of the Mississippi–Alabama barrier islands from 1972 to 2013. Each island, West Ship Island (WSI), East Ship Island (ESI), and Petit Bois Island (PBI), was measured for area in hectares 14 times per year on average with higher temporal resolution before and after hurricanes, allowing for a high-resolution statistical history of surface area change and the quanti...
Robustness of Network Centrality Metrics in the Context of Digital Communication Data

Social media data and other web-based network data are large and dynamic rendering the identification of structural changes in such systems a hard problem. Typically, online data is constantly streaming and results in data that is incomplete thus necessitating the need to understand the robustness of network metrics on partial or sampled network data. In this paper, we examine the effects of sampling on key network centrality metrics using two empirical communication datasets. Correlations between network metrics of original and sampled nodes offer a measure of sampling accuracy. The relationship between sampling and accuracy is convergent and amenable to nonlinear analysis. Naturally, larger edge samples induce sampled graphs that are more representative of the original graph. However, this effect is attenuated when larger sets of nodes are recovered in the samples. Also, we find that the graph structure plays a prominent role in sampling accuracy. Centralized graphs, in which fewer nodes enjoy higher centrality scores, offer more representative samples.
Developmental changes in sensitivity to vocal paralanguage

Developmental changes in children’s sensitivity to the role of acoustic variation in the speech stream in conveying speaker affect (vocal paralanguage) were examined. Four-, 7- and 10-year-olds heard utterances in three formats: low-pass filtered, reiterant, and normal speech. The availability of lexical and paralinguistic information varied across these three formats in a way that required children to base their judgments of speaker affect on different configurations of cues in each format. Across ages, the best performance was obtained when a rich array of acoustic cues was present and when there was no competing lexical information. Four-year-olds performed at chance when judgments had to be based solely on speech prosody in the filtered format and they were unable to selectively attend to paralanguage when discrepant lexical cues were present in normal speech. Seven-year-olds were significantly more sensitive to the paralinguistic role of speech prosody in filtered speech than were 4-year-olds and there was a trend toward greater attention to paralanguage when lexical and paralinguistic cues were inconsistent in normal speech. An integration of the ability to utilize prosodic cues to speaker affect with attention to paralanguage in cases of lexical/paralinguistic discrepancy was observed for 10-year-olds. The results are discussed in terms of the development of a perceptual bias emerging out of selective attention to language.
A family history of smoking predicts heightened levels of stress-induced cigarette craving.

Aims Individuals with histories of smoking in first-degree relatives are significantly more likely to be persistent smokers themselves. The mechanisms underlying this relationship are unknown. Considerable research has demonstrated that smokers display heightened levels of cigarette craving after being exposed to stressful situations, and the magnitude of these craving responses is thought to be predictive of later cessation failure. Based on this research, we tested experimentally the hypothesis that smokers with two or more first-degree relatives who smoked (FH + ) would exhibit stronger craving reactions following stressful stimuli than smokers without such family histories (FH‐).
A recursive segmentation and classification scheme for improving segmentation accuracy and detection rate in real-time machine vision applications

The segmentation accuracy is shown to be a critical factor in detection rate improvement. With accurate segmentation, results are easier to interpret, and classification performance is better. Therefore, it is required to have a performance measure for segmentation evaluation. However, a number of restrictions limit using existing segmentation performance measures. A recursive segmentation and classification scheme is proposed to improve segmentation accuracy and classification performance in real-time machine vision applications. In this scheme, the confidence level of classification results is used as a new performance measure to evaluate the accuracy of segmentation algorithm. Segmentation is repeated until a classification with desired confidence level is achieved. This scheme can be implemented automatically. Experimental results show that it is efficient to improve segmentation accuracy and the overall detection performance, especially for real-time machine vision applications, where the scene is complicated and a single segmentation algorithm cannot produce satisfactory results.
Toward quantum-limited position measurements using optically levitated microspheres

We propose the use of optically levitated microspheres as test masses in experiments aimed at reaching and potentially exceeding the standard quantum limit for position measurements. Optically levitated microspheres have low mass and are essentially free of suspension thermal noise, making them well suited for experimentally testing our understanding of quantum-limited measurements.
A Low Power Light Weight Wireless Multichannel Microsystem for Reliable Neural Recording

This paper reports on design and development of a reliable, single-chip, multichannel wireless biotelemetry microsystem intended for extracellular neural recording from awake, and behaving small animal models. The system requirements for reliable neural recording are identified and the inherently conflicting requirements of low power and reliability are addressed at architectural and circuit levels. The 2.85 × 3.84 mm2, mixed-signal ASIC is fabricated in a 0.5 μm 2P3M n-well standard CMOS process; and integrates a low-noise front-end, programmable digital controller, an RF modulator, and an RF power amplifier at the ISM band of 433 MHz on a single-chip. The microsystem, incorporating the ASIC, features 9-channel, is programmable, weighs 2.2 g (including batteries) and has dimensions of 2.2 × 1.1 × 0.5 cm3. The transmitter consumes 5 mW and has a measured input referred voltage noise of 4.58 μV rms, 6.20 μV rms, and 7.81 μV rms at transmission distances of 3 m, 10 m, and 20 m, respectively. The measured inter-channel crosstalk is less than 3.5% and battery life is about an hour. The presented biotelemetry system has been successfully used in two in-vivo neural recording experiments: i) from the antennas of a freely roaming South-American cockroach, and ii) from the hippocampus of an awake and mobile rat.