cssi/SciSciGPT-SciSciNet huggingface dataset:
The relation between beliefs about drug treatments for HIV and sexual risk behavior in gay and bisexual men

This study examined the relation between gay and bisexual men’s (N = 575) beliefs about highly active antiretroviral therapy (HAART) and other HIV-related beliefs, intentions, and risk behaviors. Confirmatory factor analysis verified three belief factors: the extent to which HAART improves health among HIV-infected individuals, decreases the risk of HIV transmission, and is complicated and of limited efficacy. Men who endorsed the belief that HAART decreases HIV transmission risk expressed lower intentions to use condoms for anal sex and were more likely to have engaged in unprotected anal intercourse with a casual partner. HIV-negative men who believed that HAART decreases transmission risk also perceived themselves to be more susceptible to HIV infection. Statistical evidence indicated that perceptions of susceptibility partially mediate the relation between sexual risk behavior and beliefs about HAART, suggesting that beliefs may result from, rather than cause, increased risk behavior.
Factorization for short distance hadron-hadron scattering

Abstract We show that factorization holds at leading twist in the Drell-Yan cross section dσ/dQ2dy and related inclusive hadron-hadron cross sections. We review the heuristic arguments for factorization, as well as the difficulties which must be overcome in a proof. We go on to give detailed arguments for the all order cancellation of soft gluons, and to show how this leads to factorization.
Synthetic Cash Flow Model with Singularity Functions. II: Feasible Prompt Payment Discount Scenarios

AbstractAccurately comparing balances of normal versus discounted cash flow scenarios is the key for project participants to decide whether to offer or accept a prompt payment discount. Such a decision requires determining what rates and periods are acceptable. These values are calculated through a synthetic cash flow model that uses singularity functions. Singularity functions act upon limited ranges, which is ideal for modeling financial phenomena. A signal function is derived that expresses different payment scenarios and considers the time value of money. Research contributions to the knowledge of body include the following: (1) the model can calculate the balance accurately and efficiently; (2) the new approach evaluates the feasible range for a discount from the views of both payee and payer, which is verified with an engineering economics analysis; and (3) a streamlined process for decision making using new types of nomographs is provided, so that project participants can find mutually beneficial p...
Physically routing robots in a multi-robot network: Flexibility through a three-dimensional matching graph

Many multi-robot scenarios involve navigation of a set of networked robots through a constrained environment to achieve coverage, maintain a predefined shape, sense at predefined locations, or to satisfy some other distance-defined property. When new robots and tasks are added to a network of already deployed interchangeable robots, a trade-off arises in seeking to minimize cost to execute the tasks and the level of disruption to the system. This paper examines a navigation-oriented variant of this problem in which robots are physically routed through an existing network. We propose a parametrizable method to tune emphasis between minimizing global travel cost (or energy, or distance), minimizing interruption (i.e. obtaining the fewest number of robot reassignments), reducing travel distance per robot, and completing all operations as soon as possible. Since these are related optimization criteria, a single parameter provides sufficient flexibility to balance between them. Paths through the network are computed via a task-allocation formulation in which destination locations of newly deployed robots are added as tasks to an existing allocation. We adapt the graph matching variant of the Hungarian Algorithm-originally designed to solve the optimal assignment problem in complete bipartite graphs-to construct routing paths in sparse networks. We do this by constructing a three-dimensional graph that incorporates logical aspects of the Hungarian bipartite graph, and spatial elements of the Euclidean graph. The approach has several useful features including being particularly effective at generating multiple simultaneous, non-interfering paths. When new agent-task pairs are inserted, the assignment is globally reallocated in an incremental fashion so that it requires only linear time when the robots' traversal options have bounded degree. The algorithm is studied systematically in simulation and also validated with physical robots.
Food Habits of Juvenile Pompano, Trachinotus carolinus, in Louisiana

Abstract Food habits of juvenile pompano (Trachinotus carolinus) in Louisiana were determined during the summer of 1968. Stomachs of 899 juveniles were examined from stations at Grand Isle and Holly Beach, Louisiana. The fish ranged from 10 to 125 mm in total length. Percent frequency of occurrence, percentage of total volume, and seasonal variation in diet were determined. Juvenile pompano in Louisiana ate polychaets, small clams, gastropod larvae, copepods, mysids, isopods, amphipods, postlarval shrimp, anomurans (sand crabs), brachyurans (juveniles, megalops, and eggs), insects, and small fishes. Small juveniles ate a wide variety of organisms and appeared to be opportunistic, apparently feeding on those organisms most abundant at the time. Larger juveniles ate a more limited diet, consisting primarily of coquina clams.
Impact of uneven terrain on geo-location errors for mines detected via vehicular-mounted sensors

When searching for land mines using vehicular mounted sensors, it is important that the ground locations of the detected mines be accurately determined. This is useful for data association when one has multiple looks at a mine by a single sensor or if one uses multiple sensors. It is of ultimate importance for the primary mission, which is to neutralize the detected mines or at least to mark them for avoidance. Factors that contribute to errors in geo-location include inaccurate knowledge of the vehicle position and/or attitude, and also incomplete knowledge about the terrain being searched. This paper addresses the problem of incomplete terrain knowledge and presents relationships between terrain unevenness and the resulting geo-location errors. The results of this analysis indicate that there may be significant geo-location errors for situations where the terrain is not so smooth, e.g., off road searches. The problem can be alleviated via better knowledge of the terrain. Such knowledge could be acquired via scanning the field of view with a ranging device, recording range as a function of azimuth and elevation. A variety of uneven surfaces have been simulated. Two types of sensors are considered, Linear-Array Radar and Camera Type Sensors. Geo-location is then computed based on: a) no range measurements, b) four range measurements (to the four vertices of the sensor field of view), and c) nine range measurements (to the four vertices and intermediate points at the top and bottom row, as well as three measurements across the center row). The geo-location errors are much worse for the Camera Type Sensor, but they can be significant for the Linear-Array Radar also. If the field of view is planar or almost planar, even coarse range scanning can improve geo-location accuracy. For more complex surfaces fine scanning may be required. The computed geo-location errors, and the conclusions drawn as to the effectiveness of the different models are presented in the paper.
A New Species of Pleurocrypta (Isopoda, Bopyridae), the First Known From the Western Atlantic 1)

Es wird eine neue Art der Gattung Pleurocrypta Hesse beschrieben. Die Art parasitiert Galathea rostrata. A. Milne Edwards in der Nahe von Sudflorida. Dies ist die erste Meldung dieser Gattung vom westatlantischen Ozean.
Does Screening for Barrett's Esophagus and Adenocarcinoma of the Esophagus Prolong Survival?

Despite the paucity of data supporting its use, screening upper endoscopy for patients with chronic gastroesophageal reflux disease symptoms to assess for Barrett's esophagus and esophageal adenocarcinoma has become a widely accepted practice. We apply the principles of screening to Barrett's esophagus and esophageal adenocarcinoma. Critical application of the key criteria of screening to this situation demonstrates that several criteria are unfulfilled. Key data are not available with which to judge other criteria. The major fault with screening for Barrett's esophagus is that the at-risk population is too broadly characterized and that too many cancers occur outside of this risk pool. Thus, recommendations for screening cannot be endorsed. Efforts may be better directed at further research identifying groups at risk for esophageal adenocarcinoma, developing more accurate and less-invasive methods of diagnosis, and discovering the underlying factors which continue to drive the increased incidence of this...
Mixed valency and metal–metal quadruple bonds

Abstract Linking organic conjugated systems with MM quadruple bonds (M = Mo or W) allows for the study of mixed valence metal and organic centered radicals in their ground and photo-excited states. A variety of spectroscopic studies have been employed to determine the nature of the charge distribution and the classification as Class II or III on the Robin and Day scheme.
On the crawling of animal cells

Cells crawl in response to external stimuli by extending and remodeling peripheral elastic lamellae in the direction of locomotion. The remodeling requires vectorial assembly of actin subunits into linear polymers at the lamella's leading edge and the crosslinking of the filaments by bifunctional gelation proteins. The disassembly of the crosslinked filaments into short fragments or monomeric subunits away from the leading edge supplies components for the actin assembly reactions that drive protrusion. Cellular proteins that respond to lipid and ionic signals elicited by sensory cues escort actin through this cycle in which filaments are assembled, crosslinked, and disassembled. One class of myosin molecules may contribute to crawling by guiding sensory receptors to the cell surface, and another class may contribute by imposing contractile forces on actin networks in the lamellae.
Precursor and cofactor as a check valve for cephamycin biosynthesis in Streptomyces clavuligerus.

The biosynthesis of secondary metabolites is closely linked to primary metabolism via the supply of precursors, cofactors, and cellular energy. The availability of these precursors and cofactors can potentially be rate-limiting for secondary metabolism. A combined experimental and kinetic modeling approach was used to examine the regulation of flux in the cephamycin biosynthetic pathway in Streptomyces clavuligerus. The kinetic parameters of lysine 6-aminotransferase (LAT), the first enzyme leading to cephamycin biosynthesis and one which was previously identified as being a ratelimiting enzyme, were characterized. LAT converts lysine to R-aminoadipic acid using R-ketoglutarate as a cosubstrate. The Km values for lysine and R-ketoglutarate were substantially higher than those for their intracellular concentrations, suggesting that lysine and R-ketoglutarate may play a key role in regulating the flux of cephamycin biosynthesis. The important role of this precursor/cosubstrate was supported by simulated results using a kinetic model. When the intracellular concentrations and high Km values were taken into account, the predicted intermediate concentration was similar to the experimental measurements. The results demonstrate the controlling roles that precursors and cofactors may play in the biosynthesis of secondary metabolites.
Trans-disubstituted tetraarylporphyrin as a precursor to larger molecular architectures: an application of MacDonald "2 + 2" porphyrin synthesis in aqueous anionic surfactant.

The trans-meso-disubstituted tetraarylporphyrin 2 was synthesized in 16−25% yield by the MacDonald “2 + 2” procedure using acidified aqueous sodium dodecyl sulfate as the reaction medium. No scrambling was observed. The demethylation of 2 and subsequent reaction with HB(3,5-Me2Pyz)3OMoV(OCH2CH2O) gave 1.
Purchasing power parity: Evidence from a transition economy

Abstract Whether the purchasing power parity (PPP) theory of exchange rate determination holds for transition economies is an interesting question, given peculiar situations of transition economies. In this paper, we examine the real exchange rate for Croatia, a transition economy that has had some success in moving towards a market economy. Using a battery of tests that allow for a maximum of two structural breaks whose locations are determined endogenously from the data, we failed to find evidence supporting the validity of PPP for the Croatian economy. Thus, the conjecture that transition economies experiencing growth in productivity and real wages should experience real appreciation (thereby introducing doubt as to whether purchasing power parity holds) is substantiated by our results.
Model studies of the Si(111)2 × 1 surface by the pseudofunction method

Abstract The recently developed pseudofunction (PSF) slab calculational method is used to study the electronic structure and total energy of the uniformly relaxed, buckling, and Pandey's chain-like reconstruction of the Si(111)2 × 1 surface. It is found Pandey's π bonded chain model is the most favorable by − 0.54 eV surface atom relative to the ideal surface. For the uniformly relaxed case the equilibrium relaxation and the vibrational excitation agree well with generalized valence bond (GVB) calculations. Pandey's chain model yields a surface-resonance band resembling well that of Northrup and Cohen from Γ to J′. An equilibrium surface chain bond length of 2.28 A is obtained with a bare 6-layer slab. However, an expanded or unstable surface chain is found when the dangling bonds on opposite side surface are saturated with either an H layer or a Cl layer. Thus, results for thin semiconductor slabs may be model-dependent.
Neural activity in the medial geniculate nucleus during auditory trace conditioning

In classical trace conditioning the acquisition of a conditioned response (CR) is possible even though an interval (the trace interval) elapses between the conditioned stimulus (CS) and unconditioned stimulus (US). This implies that some neural representation of the CS (the stimulus trace) is able to support association between the two stimuli. The medial geniculate nucleus (MGN), particularly the medial division (mMGN), has been identified as one site in the auditory pathway where associative related changes in neural activity occur. If neurons in the MGN are involved in such a sensory trace and in acquisition of a CR, then it is expected that activity following an acoustic CS should be related to both stimulus and response. This study examined the extracellular activity of single units in the MGN during differential auditory trace conditioning of the rabbit nictitating membrane response (NMR). Two 150-ms tones (600 Hz and 1200 Hz) served as CS+ and CS–, and the US was periorbital electrostimulation. Changes in activity during the stimulus and trace interval were largest in the medial and dorsal MGN divisions on CS+ trials and on trials in which a CR was made. Examination of probe stimuli of short (50 ms) and long (600 ms) duration suggested that both CR latency and activity changes in the trace interval were related to stimulus duration and time-locked to stimulus offset. Comparisons of neural activity on the basis of fast or slow CR responses revealed different patterns of response – activity on fast CR trials was generally greater and tended to occur earlier. These results suggest that MGN neurons are involved in the maintenance of a sensory memory trace and possibly play a part in CR generation and timing.
Marking Otoliths and Fin Spines of Juvenile Shortnose Sturgeon with Oxytetracycline and the Effects of Water Temperature during Treatment

Abstract In order to evaluate a stocking program for shortnose sturgeon Acipenser brevirostrum that uses captive propagation to supplement wild populations, methods are needed to differentiate wild and hatchery-reared individuals. Recently, methods have been established for marking juvenile shortnose sturgeon in oxytetracycline hydrochloride (OTC) baths, and the marks have been confirmed on both sagittal otoliths and first-ray pectoral fin spines. However, considerable variability of mark quality has been observed on both structures, and sacrificing the fish for otolith removal is undesirable due to the shortnose sturgeon's endangered status. The objectives of this study were to determine the impact of water temperature during OTC marking on otolith and fin spine mark quality and to determine whether fin spines are as reliable as otoliths for detecting OTC marks. Six groups (N = 90) of hatchery-produced shortnose sturgeon fingerlings were exposed to 750-mg/L OTC baths for 12 h at two temperatures (heated ...
Conformal covariance and the probability interpretation of wave equations

Abstract The Dirac and the Schrodinger fields are singled out among all other fields by their conformal dimension l = − 3 2 , a necessary condition for the field to have also a probability interpretation as a wave function. The correct dimension of the Schrodinger field comes about by an intricate contraction of the conformal group to the Schrodinger group.
Realism, antirealism and epistemic truth

Critique des theories coherentistes de la verite et de la justification developpees par L. Alcoff dans son ouvrage intitule «Real knowing: new versions of the coherence theory» (1996). Reperant une forme d'antirealisme dans la position de L. Alcoff, l'A. deplore l'absence d'une reflexion sur les problemes essentiels de l'antirealisme concernant la notion de constitution, sa reconciliation avec le protorealisme et sa coherence interne. Exposant sa conception independante de l'esprit du protorealisme, ainsi que sa definition mereologique de la constitution, l'A. rejette le realisme metaphysique de Putnam et defant l'autonomie de l'epistemologie face a la metaphysique
Maximizing the Utility of a Computer Service using Adaptive Optimal Control

This paper describes a control system that aims to maximize the value or utility obtained from a computer service (e.g., e-commerce system and networked file system) that is shared by multiple customers. Each customer has negotiated contractual performance objectives, such as response time bounds and minimum throughput bounds, with the service provider. It is the service provider's goal to maximize the utility it gets from serving these customers workloads less any penalties for not meeting the contracted performance goals. Our design consists of a MIMO adaptive optimal controller coupled with a nonlinear optimizer. The optimizer uses the model produced by the estimator in the adaptive controller to calculate the performance goals that will maximize the utility of the service. These goals are the references to the controller that aims to meet these by dynamically allocating the share of computing resources that each customer will receive. Experimental results from a 3-tier e-commerce site shows that our approach can indeed meet latency and throughput goals and maximize the utility of the system, even when the system and the workload change significantly.
On Coleman's theorem for scale invariance

Abstract If the dilatation charge annihilates the vacuum presence of zero mass states (or complete scale invariance) follows.
A balanced force refined level set grid method for two-phase flows on unstructured flow solver grids

A balanced force refined level set grid method for two-phase flows on structured and unstructured flow solver grids is presented. To accurately track the phase interface location, an auxiliary, high-resolution equidistant Cartesian grid is introduced. In conjunction with a dual-layer narrow band approach, this refined level set grid method allows for parallel, efficient grid convergence and error estimation studies of the interface tracking method. The Navier-Stokes equations are solved on an unstructured flow solver grid with a novel balanced force algorithm for level set methods based on the recently proposed method by Francois et al. [M.M. Francois, S.J. Cummins, E.D. Dendy, D.B. Kothe, J.M. Sicilian, M.W. Williams, A balanced-force algorithm for continuous and sharp interfacial surface tension models within a volume tracking framework, J. Comput. Phys. 213 (2006) 141-173] for volume of fluid methods on structured grids. To minimize spurious currents, a second order converging curvature evaluation technique for level set methods is presented. The results of several different test cases demonstrate the effectiveness of the proposed method, showing good mass conservation properties and second order converging spurious current magnitudes.
The effect of inorganic phosphate on chick (Gallus domesticus) heart mitochondrial volume and cation content.

Abstract 1. 1. In the absence of exogenous Ca(II), P i induces a swelling change that is kinetically first order with k = 1.08 ± 0.1 min −1 . The first-order rate constant is independent of [P i ] over the range 0.5–45 mM. 2. 2. In the presence of exogenous substrate, the volume change induced by P i is monophasic and can be reversed by ADP. 3. 3. The swelling process and the approach to steady state is accompanied by controlled losses of both K + and Mg(II) from within the mitochondria. 4. 4. The loss of K + is biphasic as a function of time with K 1 = 14.1 ± 1.6 and k 2 = 4.4 ± 0.34 nmol min −1 mg mitochondria −1 . 5. 5. The loss of Mg(II) is monophasic and the rate at which this cation is released decreases as a function of time. Ca(II) fluxes are not involved in the volume occurring secondary to P i uptake. 6. 6. In the absence of exogenous substrate, P i induces a triphasic change in mitochondrial volume. 7. 7. The sequence of volume changes corresponds to an initial first-order swelling secondary to the addition of P i , a contraction apparently triggered by the loss of approximately 85% of total intra-mitochondrial Mg(II), and a second larger swelling phase that cannot be reversed with ADP. 8. 8. The P i -induced swelling of chick heart mitochondria is not inhibited by EGTA and does not depend on the provision of exogenous Ca(II). 9. 9. The Ca(II) and Mg(II) ions released from within the mitochondria are responsible for activating divalent cation-dependent ATPases which cosediment with isolated chick heart mitochondria.
Ophthalmologic outcome after third cranial nerve palsy or paresis in childhood.

Abstract Purpose: The purpose of this study was to evaluate the causes and ophthalmologic outcome of oculomotor nerve palsy or paresis in children younger than 8 years of age. Methods: Patients evaluated between 1985 and 1997 were retrospectively reviewed. Data analyzed included vision, residual strabismus after surgery, aberrant reinnervation, binocular function, and anisometropia. Long-term outcome was assessed in patients followed-up longer than 6 months. Results: Forty-one patients were identified. The most frequent causes were congenital (39%), traumatic (37%), and neoplastic (17%). Visual acuities were reduced in 71% of patients at the time of the initial visit. Long-term outcome could be assessed in 20 of the 41 patients (49%), with a mean follow-up of 3.6 years (range, 0.5 to 13 years). Visual acuities were reduced because of amblyopia in 35% and nonamblyopic factors in 25% of patients in the long-term outcome group at last follow-up. The best response to amblyopia therapy was in the congenital group, in which all patients improved to normal visual acuity. Strabismus surgery was performed on 8 of 20 children (40%) followed-up, none of whom demonstrated measurable stereopsis after operation despite improved alignment. Aberrant reinnervation was present in 9 of 20 patients (45%). Only 3 patients fully recovered from their oculomotor nerve injuries, and these were the only patients to regain measurable stereopsis. The causes in those 3 patients were congenital, traumatic, and neoplastic. Conclusions: Oculomotor nerve palsy/paresis is associated with poor visual and sensorimotor outcome in children younger than 8 years of age. The best ophthalmologic outcome was in the resolved cases (3 of 20; 15%). Amblyopia therapy was most effective with congenital causes, but treatment results were poor with other causes. Young children with posttraumatic and postneoplastic oculomotor nerve injuries demonstrated the worst ophthalmologic outcomes. (J AAPOS 1999;3:2-8)
Repeatability of Full-Scale Crash Tests and Criteria for Validating Simulation Results:

A method of comparing two acceleration time histories to determine whether they describe similar physical events is described. The method can be used to assess the repeatability of full-scale crash tests and it can also be used as a criterion for assessing how well a finite-element analysis of a collision event simulates a corresponding full-scale crash test. The method is used to compare a series of six identical crash tests and then is used to compare several finite-element analyses with full-scale crash test results.
CyberKnife robotic radiosurgery system for tumor treatment.

Defined by its high level of accuracy and rapid radiation dose fall-off, radiosurgery has emerged as an effective radiation technique over the past few decades. Although it was once limited to conditions of the brain, head and neck regions, technological advances in computing and imaging have allowed the application of radiosurgery to conditions throughout the entire body. Using advanced imaging and robotics, the CyberKnife® (Accuray, Inc., Sunnyvale, CA, USA) is one of few systems capable of delivering radiosurgery with exquisite accuracy to tumors, cancers and other conditions throughout the body. This review focuses on the development, technology, clinical efficacy and future directions of the CyberKnife.
Monolithic integration of GaAs light-emitting diodes and Si metal-oxide-semiconductor field-effect transistors

A monolithic optoelectronic circuit, consisting of a GaAs light‐emitting diode (LED) driven by a Si metal‐oxide‐semiconductor (MOS) transistor, has been fabricated. Light output as a function of applied gate voltage was measured. The LED’s were fabricated in GaAs layers on Ge‐coated Si substrates containing MOS transistors. Normal transistor performance was observed after the GaAs LED fabrication, indicating that GaAs and Si processing technologies appear to be compatible.
Participation in a School Incentive Programme in India

Abstract Education policy has recently focused on improving accountability and incentives of public providers for actual learning outcomes, often with school-based reward programmes for high performers. The Learning Guarantee Programme in Karnataka, India, is prominent among such efforts, providing cash transfers to government schools that achieve learning at specified high levels. This study examines whether schools that self-selected into the incentive programme are different than those that did not. The answer has important implications for how to evaluate the impact of such a programme. Although we find no significant differences in resources and characteristics, we do find significant and substantial differences in test scores prior to selection into the programme, with better performing schools more likely to opt-in. These findings also provide insight into how incentive-based programmes that focus on levels of (rather than changes in) achievement can exacerbate inequality in education. Failing scho...
Photodissociation of silicon carbide cluster cations

Abstract Small clusters of silicon carbide ( Si x C y + , x = 3 – 10 , y = 1 – 2 ) are produced by laser vaporization in a pulsed molecular beam and detected with time-of-flight mass spectrometry. Specific clusters are mass selected and photodissociated at 355 nm. Si3C+ is an especially abundant cluster in the mass spectrum, and it is produced often as a fragment from larger clusters, suggesting that it is relatively more stable than other small cations. The smaller clusters (Si3–5C+) fragment primarily by the loss of neutral Si atoms, while larger clusters (Si7–10C+) lose neutral Si2C and Si3C, which are concluded to be more stable neutrals.
The Drosophila gene knirps-related is a member of the steroid-receptor gene superf amily

Molecular cloning has demonstrated that the receptors for steroid, retinoid and thyroid hormones are part of a large superfamily of nuclear regulatory proteins. In vertebrates these molecules regulate diverse biological processes such as pattern formation, cellular differentiation and homeostasis1. The universal necessity for embryonic and adult cells to respond to their external environment might mean that members of this family pre-date the divergence of vertebrates and invertebrates. We have screened a Drosophila genomic library for steroid receptor homologues using a human retinoic acid receptor complementary DNA2,3 as a hybridization probe. Several clones were recovered, one of which mapped to chromosomal position 77E1-2, the cytological location of the gap segmentation gene knirps4. Sequence analysis of a cDNA clone representing the human retinoic acid receptor homologue showed similarity of the predicted protein to the vertebrate steroid receptors, as well as to the predicted knirps5 gene product. In situ hybridization of a cDNA probe to wild-type embryos revealed a uniform distribution of transcripts that were apparently maternally derived. Zygotic transcript accumulation begins in a broad anteroventral domain before the cellular blastoderm stage. At the cellular blastoderm stage two additional circumferential bands of tran-script appear.
Ambulatory electrocardiography and the diagnosis, evaluation, and treatment of chronic ventricular arrhythmias.

D URING the past 15 yr there has been widespread interest in ventricular arrhythmias and sudden death. During this period, technical advances have improved our ability to record continuous electrocardiograms in ambulatory patients as they go about routine daily activities. Consequently, our knowledge of the prevalence and prognostic significance of chronic ventricular arrhythmias has increased. We have learned a lot about the prevalence of chronic ventricular arrhythmias in populations free of cardiac disease and in a variety of specific cardiac conditions. Additionally, our understanding of the relationship between symptoms suggesting ventricular arrhythmias and the occurrence of ventricular arrhythmias and the hour-to-hour and day-to-day variability of these rhythms has been enhanced through widespread use of ambulatory electrocardiographic monitoring. During this same period there has been interest in better understanding ventricular arrhythmias and the actions and clinical pharmacology of antiarrhythmic drugs. Many new drugs have been developed for treatment of chronic ventricular arrhythmias. Ambulatory electrocardiography has made important contributions to selecting patients who require drug therapy and in evaluating the efficacy of such therapy. This article reviews the contributions of ambulatory electrocardiography to the diagnosis, evaluation, and treatment of chronic ventricular arrhythmias.
Spin relaxation and linear-in-electric-field frequency shift in an arbitrary, time-independent magnetic field

A method is presented to calculate the spin relaxation times T{sub 1}, T{sub 2} due to a nonuniform magnetic field, and the linear-in-electric-field precession frequency shift {delta}{omega}{sub E} when an electric field is present, in the diffusion approximation for spins confined to a rectangular cell. It is found that the rectangular cell geometry admits of a general result for T{sub 1}, T{sub 2}, and {delta}{omega}{sub E} in terms of the spatial cosine-transform components of the magnetic field.
Engineered Disulfide Bonds in Staphylococcal Nuclease: Effects on the Stability and Conformation of the Folded Protein†

Efforts to enhance the stability of proteins by introducing engineered disulfide bonds have resulted in mixed success. Most approaches to the prediction of the energetic consequences of disulfide bond formation in proteins have considered only the destabilizing effects of cross-links on the unfolded state (chain entropy model) [Pace, C. N., Grimsley, G. R., Thomson, J. A., & Barnett, B. J. (1988) J. Biol. Chem. 263, 11820−11825; Doig, A. J., & Williams, D. H. (1991) J. Mol. Biol. 217, 389−398]. It seems clear, however, that disulfide bridges also can influence the stability of the native state. In order to assess the importance of the latter effect, we have studied four variants of staphylococcal nuclease (V8 strain) each containing one potential disulfide bridge created by changing two wild-type residues to cysteines by site-directed mutagenesis. In each case, one of the introduced cysteines was within the type VIa β turn containing cis Pro117, and the other was located in the adjacent extended loop cont...
Evaluation of scanning cytometer fluorometry performance

Recent advances in autofocus, image segmentation, and fluorescence lamp stabilization have resulted in a fully automated high-speed image cytometer. This system performs computer-controlled autofocus, incremental stage scanning, image processing and data storage at a combined 1 Hz field rate. DAPI stained 3T3 cells that were cultured on microscope cover slips were scanned using the scanning cytometer. The integrated intensity for each detected cell object was computed and stored as well as its area and information about its location. Performance of the system was evaluated by repeatedly scanning cellular objects and comparing the results of each object over several hundred scans. This method of performance evaluation has the advantage of being independent of variations in stain homogeneity of the slide being scanned. For several hundred repeat scans, coefficients of variation (CVs) of significantly less than 1% were consistently obtained for the integrated intensity of each cellular object in the experiment.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Railroad productivity analysis: case of the American Class I railroads

Purpose – The purpose of this paper is to provide an economic assessment of the productivity growth and technical efficiency of US Class I railroads for the period of 2002‐2007.Design/methodology/approach – The US railroad industry has become increasingly concentrated with seven Class I railroads accounting for over 90 percent of the industry's revenue. Because the small sample size creates a dimensionality problem for data envelopment analysis (DEA) with contemporaneous frontiers, the authors use sequential DEA and calculate the Malmquist productivity indexes using sequential frontiers. Through a decomposition process, changes in productivity are attributed to technical efficiency change, technical change, and scale efficiency change.Findings – Burlington Northern Santa Fe (BNSF) led the industry in terms of productivity growth (4.6 percent) and consistently stayed on the production frontier in every period studied; both BNSF and Union Pacific (UP) are top innovators in the industry, but UP trailed BNSF ...
Sub-30 nm abrupt P+ junction formation with Ge preamorphization and high energy Si Co-implantation

Experiments have been caried out to form ultra-shallow (Xj <50nm) and abrupt (Xjs < 5nm/decade) P’junction for sub-50 nm CMOS devices using a combination of shallow implant, Ge preamorphization and high energy Si implant as an interstitial getter layer. Experimentally, it was observed that the Si getter layer, not only stopped the TED at the boron tail but also promoted enhanced diffusion close to the surface boron peak. These unique features have enabled the shallowest and sharpest box-like boron junction yet achieved by implant. With I kV BF2, Xj ~ 23 nm, Xjs ~ 48 A/decade, no Ge end of range damages and good dopant activation at the same time.The sheet resistance ρ - 1 kohm/sq is comparable to shallow BF2 + Ge and is better than the shallow BF 2 alone (ρ ~ 2.38 kO/sq) or the shallow BF2 + Si implants (ρ ~ 1.5 kohm/sq). Tests with device leakage test structures show that there is no additional junction leakage introduced by the Si getter layer.
The Effects of Mood on Expository Writing

Past research has shown that analytical writing and problem solving may be influenced by mood and that experiencing intense mood states may be a catalyst for creativity. This experiment sought to test the hypothesis that good and bad moods have differential effects on expository writing. Sixty-two participants were asked to write a fictional story, a non-fictional story, or story of their choosing when they were in either a good or a bad mood. They then completed a questionnaire that assessed their mood again. The results of this study showed that good moods were associated with the stories that expressed positive emotions, used a narrative style, and conveyed concrete concepts, but bad moods were associated with the stories that expressed negative emotions, used a diary style, and discussed abstract concepts.
Passive multipoint moment matching model order reduction algorithm on multiport distributed interconnect networks

In this paper, we introduce a general method of interconnect simulation based on distributed circuits. The algorithm is very efficient and consists of two main steps. In the first step, each distributed line is modeled by a finite order system with passivity preservation and multipoint moment matching of its input admittance/impedance matrix. In the second step, an Arnoldi-based congruence transform is applied to the network to form its reduced order model. The main feature of the algorithm is in its first step, where a passive multipoint moment matching model of a distributed line can be generated without any discretization of the line. We provide an integrated-congruence transform which can be directly applied to the partial differential equations of a distributed line and generate a passive finite order system as its model. We also provide an algorithm based on the L/sup 2/ Hilbert space theory so that exact moment matching at multiple points can be obtained, We demonstrate the accuracy of our method with examples and show the advantage of ours over conventional ones based on lumped circuit models.
Long QTc Syndrome Type 2 Presenting in a Postpartum Patient on Medroxyprogesterone

Introduction. Congenital long QT syndrome type 2 (LQTS2) is a rare inherited cardiac abnormality resulting in increased risk of polymorphic ventricular tachycardia (PVT). Case Description. A 21-year-old postpartum female presented with syncopal episode after phone alarm. She was noted to have PVT on telemetry monitoring in the emergency department. EKG revealed QTc of 530. The patient’s only medication was medroxyprogesterone. She ultimately received a dual chamber pacemaker with ICD. Discussion. LQTS2 is associated with alarm sounds as a precipitating factor. Postpartum hormonal shifts as well as medroxyprogesterone have significant effect on native QTc duration.
Impact of complex wireless environments on rate adaptation algorithms

Due to the popularity of mobile computing devices, 802.11-based wireless networks have become common place. A critical but unspecified component of 802.11 is transmission rate adaptation. Rate adaptation is difficult to do because it requires accurately estimating channel conditions while experiencing distinctly different wireless phenomena such as multi-path fast fading, nodal mobility, environmental mobility and hidden terminal interference. Rate adaptation algorithms use various methods to estimate channel conditions but these methods can be inaccurate in complex wireless environments causing incorrect adaptations. In this paper, we investigate the impact of inaccurate channel estimation methods by studying two rate adaptation algorithms, CHARM and SampleRate. We emulate high fidelity versions of both algorithms, using QualNet and evaluate their performance under environmental mobility and hidden terminal interference conditions. We found that the performance of both algorithms degrade dramatically due to inaccurate estimations caused by stale channel information. We propose two optimization techniques, REGS SINR and IntRec, to counteract these inaccuracies and implement them for CHARM and SampleRate. The proposed optimization techniques increase the performance dramatically for CHARM, up to 340% for environmental mobility and more than 290% for hidden terminal interference. We saw similar improvements of 220% and 88% for SampleRate.
Use of isotopes in the diagnosis of hematopoietic disorders

Isotopes of iron have been paramount in clinical tracer studies of hematopoiesis. Kinetics of disappearance from plasma, appearance in circulating erythrocytes, and localization in general areas of bone marrow, spleen, and liver were early revealed by gamma-/beta-emitting Fe-59 with note of characteristic differences of kind and degree of dysfunction among various anemias. Findings have helped in management (e.g., decisions about splenectomy). Positron/gamma-emitting Fe-52 (better for imaging) has provided more detail on marrow expansion and erythropoietic relocation. Other gamma-emitting tracers of hematopoiesis have been In-111 (linked to transferrin) and technetium 99m (Tc-99m) colloids (localizing to reticuloendothelial cells, which have close association with blood cell progenitors), but Fe-52 has proved to be more accurate for recognition of erythropoiesis. Occasional diverse heterotopic sites of hematopoiesis beyond spleen and liver in states of bone marrow disease have posed diagnostic challenges and also raised questions about migration and/or activation of stem cells. Studies of granulopoiesis utilize Tc-99m–labeled leukocytes or Tc99m-labeled antibodies to circulating and progenitor white cells. Iron-deficiency anemias due to malnutrition, malabsorption, blood loss, or special need are explored by dual study (oral vs intravenous) with radioactive (Fe-59, Fe-55) or stable (Fe-54, Fe-57) iron isotopes, which can guide dietary supplementation. Tests for B-12 deficiency in pernicious anemia or malabsorption with radioisotopes of cobalt (Co-57, Co-58) have been upgraded in sensitivity and scope. Rates of oxidation to expired carbon dioxide from particular carbon (radioactive C-14 or stable C-13)−labeled compounds can test B-12 or folic acid deficiencies or gastric infestation as causes of megaloblastic anemias.
Adaptive Part Inspection Through Developmental Vision

We present a novel online inspection method for manufacturing processes that automatically adapts to variations in part and environmental properties. This method is based on a developmental learning architecture comprising a procedure that focuses attention to apparently defective regions, a recognition method that performs automatic feature derivation based on a set of training images and hierarchical classification, and an action step that controls attention and further decision processes. The method adapts to variations incrementally by updating rather than recreating the training information. Also, the method is capable of inspecting and training simultaneously. Addressing new inspection tasks requires neither re-programming and compatibility tests, nor quantitative knowledge about the image set, from a human developer. Instead, automatic or manual training of the inspection system according to simple guidelines is applied. These attributes allow the method to improve online performance with minimal ramp-up time. Our system performed inspection of three applications with low error rate and fast recognition, confirming its suitability for general-purpose, real-time, online inspection. DOI: 10.1115/1.2039103
A lady in distress: Inhibiting effects of friends and strangers on bystander intervention ☆

Abstract One hundred twenty male undergraduates waiting either alone, with a friend, or with a stranger, overheard a woman fall and cry out in pain. Two-person groups were less likely to offer help to the injured woman than were subjects who overheard the emergency while alone. Pairs of friends were less inhibited from intervening than were strangers and helped significantly faster. In this ambiguous situation, each bystander may look to others for guidance before acting, misinterpret their apparent lack of concern, and decide the situation is not serious. Friends seem less likely to misinterpret each other's initial inaction than strangers.
Upgrading of crude oil via in situ combustion

Abstract Crude oil upgrading is of major economic importance. Heavy crude oils exist in large quantities in the western hemisphere, but are difficult to produce and transport because of their high viscosity. Some crude oils contain compounds such as sulfur and/or heavy metals causing additional refining problems and costs. In situ upgrading could be a very beneficial process for leaving the unwanted elements in the reservoir and increasing API gravity. In situ combustion has long been used as an enhanced oil recovery method. For heavy oils, numerous field observations have shown upgrading of 2° to 6° API for heavy oils undergoing combustion [Ramey, H.J., Jr., Stamp, V.V., Pebdani, F.N., 1992. Case History of South Belridge, California, In Situ Combustion Oil Recovery, SPE 24200, Proc. 9th SPE/DOE EOR Symposium, Tulsa, April 21–24.]. During in situ combustion of heavy oils, temperatures of up to 700 °C can be observed at the combustion front. This paper describes the changes caused by the various reactions occurring during combustion with emphasis on the upgrading potential for various oil types. We will first describe the in situ combustion process with an examination of the temperature changes and chemical reactions that can either upgrade or degrade the oil in terms of its API gravity and viscosity. In the second part, we present results from three combustion tube runs aimed at sulfur removal. We will end by discussing possible in situ upgrading strategies using combinations of in situ combustion and other improved recovery methods.
Computer Analysis of Arterial Properties

Use of an analog computer for determination of mechanical properties of the arterial bed is described. This approach involves mathematical operations on a recorded central pulse to produce a computed peripheral pulse and computer parameters varied until matching is accomplished. Values for arterial elasticity, etc. are calculated from the computer settings.
Beam dynamics simulations for a DC gun based injector for PERL

The National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory (BNL) is considering an upgrade based on the Photoinjected Energy Recovering Linac (PERL). The various injector schemes for this machine are being extensively investigated at BNL. One of the possible options is photocathode DC gun. The schematic layout of a PERL DC gun based injector and its preliminary beam dynamics are presented in this paper. The transverse and longitudinal emittance of photoelectron beam were optimized for a DC field of 500 kV.