cssi/SciSciGPT-SciSciNet huggingface dataset:
Criticality of Railroad Training

With the advent of Positive Train Control (PTC), railroads have significantly expanded their communications, signaling, networking and information technology systems. This has required training for existing staff as well as new staff with experience in these areas from industries other than railroading. At the same time, railroads must ensure that maintenance and operations are supported by properly trained employees who execute their responsibilities consistent with regulatory and railroad requirements. Certainly, this is the case for the vast majority of railroad employees; however, in those rare instances when employees deviate from their training, the results can be catastrophic. This has played out recently at Metro North Railroad, which has suffered five accidents over a ten month period, resulting in six fatalities, one hundred and twenty-eight injuries and twenty-eight million dollars in property damage.The lessons from these tragedies, from the perspective of human behavior, and more specifically, training is discussed. Indeed, these accidents, in part, occurred because the railroad’s training program did not achieve its desired outcome, to mold human behavior; especially while performing safety-critical work. This is consistent with the findings of a recent Federal Railroad Administration (FRA) safety review of Metro North Railroad, which found ineffective training was at least in part to blame for the aforementioned rash of accidents.The rigorous training requirements, that are part of the Rail Safety Improvement Act of 2008 (RSIA), are detailed. These requirements are intended to ensure that employees are properly prepared to maintain and operate these complex systems and have the added benefit of helping to prepare new employees to take the place of departing, highly experienced individuals. Recognizing the criticality of this training, this paper details training best practices and how they can most effectively be leveraged by railroads. Properly applied, they can reduce accidents, stem the loss of institutional knowledge and properly prepare railroad staff to maintain and operate their new PTC systems.This paper discusses how comprehensive training programs should be built on a foundation of organizational understanding, created by conducting training needs analysis. This analysis seeks to identify the current state of knowledge of key personnel, and compares it to that needed to properly support new organizational goals, such as to maintain and operate PTC. These organizational goals, coupled with the training needs analysis findings, then drive the enhancement of existing training programs, and, in some cases, the creation of new programs. In order to maximize effectiveness of these programs, it was found that training must be conducted using real-life case studies and in a manner that is engaging and interactive.© 2015 ASME
Improved control of asthma in the office setting: A large-scale study of once-daily evening doses of theophylline

A large-scale, multi-investigator open evaluation compared a once-daily regimen of controlled-release theophylline (Uniphyl tablets) with previous twice- or thrice-daily methylxanthine regimens. Three hundred asthmatic patients, 78 percent prone to nocturnal episodes during prior therapy, completed the investigation. Eighty-two percent of the patients were treated for moderate or severe disease. After a one-week evaluation of baseline theophylline therapy (with adjunctive medication), the patients substituted evening doses of the once-daily drug in approximate milligram-for-milligram equivalent doses. Concomitant medications were allowed as before. Nighttime and morning asthma control improved significantly without deterioration in the evening, and without increased side effects. Once-daily therapy resulted in markedly fewer night awakenings involving inhaler use (p less than 0.01), and near 60 percent reductions in the number of patients with nighttime or early morning exacerbations (p less than 0.01). Control of morning chest tightness, wheeze, and dyspnea improved significantly (p less than 0.01), and patients' as well as investigators' global evaluations favored once-daily treatment (p less than 0.01). Morning peak expiratory flow rates improved both at home (p less than 0.01) and at the office (p = 0.05). The forced expiratory volume in one second at the office increased modestly in the entire group. It is concluded that Uniphyl is effective and well tolerated when administered in once-daily evening doses.
Combining Geometric- and View-Based Approaches for Articulated Pose Estimation

In this paper we propose an efficient real-time approach that combines vision-based tracking and a view-based model to estimate the pose of a person. We introduce an appearance model that contains views of a person under various articulated poses. The appearance model is built and updated online. The main contribution consists of modeling, in each frame, the pose changes as a linear transformation of the view change. This linear model allows (i) for predicting the pose in a new image, and (ii) for obtaining a better estimate of the pose corresponding to a key frame. Articulated pose is computed by merging the estimation provided by the tracking-based algorithm and the linear prediction given by the view-based model.
Van Allen Probe observations of periodic rising frequencies of the fast magnetosonic mode

Near simultaneous periodic dispersive features of fast magnetosonic mode emissions are observed by both Van Allen Probes spacecraft while separated in magnetic local time by ~5 h: Probe A at 15 and Probe B at 9–11 h. Both spacecraft see similar frequency features, characterized by a periodic repetition at ~180 s. Each repetition is characterized by a rising frequency. Since no modulation is observed in the proton shell distribution, the plasma density, or in the background magnetic field at either spacecraft we conclude that these waves are not generated near the spacecraft but external to both spacecraft locations. Probe A while outside the plasmapause sees the start of each repetition ~40 s before probe B while deep inside the plasmasphere. We can qualitatively reproduce the dispersive features but not the quantitative details. The cause for this phenomena remains to be identified.
The complete mitochondrial genome of the Warm Springs pupfish, Cyprinodon nevadensis pectoralis

AbstractIn this article we report the complete mitochondrial genome of the Warm Springs pupfish, Cyprinodon nevadensis pectoralis. The genomic DNA of a single female individual was extracted and sequenced on the Illumina HiSeq2000 platform. It contains 16,499 bp and a total of 37 genes, divided into 22 tRNA genes, 2 rRNA genes and 13 protein-coding genes. It exhibits 94% sequence similarity with the other published mitochondrion in its genus, C. rubrofluviatilis. A Tamura–Nei maximum-likelihood tree constructed from mitochondrial sequences shows expected phylogenetic relationships between C. nevadensis and sister taxa.
Bridges to Sexual Desire

This paper presents a cognitive-behavioral approach to understanding and treating inhibited sexual desire. It emphasizes strategies to prevent desire problems, interventions when they occur, and techniques to maintain desire and prevent relapse. Special attention is focused on five components of sexual desire: Anticipation, owning your sexuality, preserving sexual pleasure, arousal and orgasm dysfunction, and valuing intimate sexuality.
Coexpression of two closely linked avian genes for purine nucleotide synthesis from a bidirectional promoter.

Abstract Two avian genes encoding essential steps in the purine nucleotide biosynthetic pathway are transcribed divergently from a bidirectional promoter element. The bidirectional promoter, embedded in a CpG island, directs coexpression of GPAT and AIRC genes from distinct transcriptional start sites 229 bp apart. The bidirectional promoter can be divided in half, with each half retaining partial activity towards the cognate gene. GPAT and AIRC genes encode the enzymes that catalyze step 1 and steps 6 plus 7, respectively, in the de novo purine biosynthetic pathway. This is the first report of genes coding for structurally unrelated enzymes of the same pathway that are tightly linked and transcribed divergently from a bidirectional promoter. This arrangement has the potential to provide for regulated coexpression comparable to that in a prokaryotic operon.
Determining customer satisfaction in anatomic pathology.

Abstract Context.—Measurement of physicians' and patients' satisfaction with laboratory services has become a standard practice in the United States, prompted by national accreditation requirements. Unlike other surveys of hospital-, outpatient care–, or physician-related activities, no ongoing, comprehensive customer satisfaction survey of anatomic pathology services is available for subscription that would allow continual benchmarking against peer laboratories. Pathologists, therefore, must often design their own local assessment tools to determine physician satisfaction in anatomic pathology. Objective.—To describe satisfaction survey design that would elicit specific information from physician customers about key elements of anatomic pathology services. Design.—The author shares his experience in biannually assessing customer satisfaction in anatomic pathology with survey tools designed at the Henry Ford Hospital, Detroit, Mich. Benchmarks for physician satisfaction, opportunities for improvement, and...
The Role of Eucaryotic Elongation Factor Tu in Protein Synthesis

A sensitive radioimmunoassay for eucaryotic elongation factor Tu (eEF-Tu) was developed using radioiodinated elongation factor T (eEF-T) and goat anti-(rabbit eEF-T) immunoglobulins coupled to a solid support. eEF-T was iodinated with 125I to a specific activity of 7 × 103 counts min−1 ng−1 using a system employing lactoperoxidase and glucose oxidase coupled to a solid support. The assay exhibits a limit of detection of about 1 ng eEF-Tu and an intraassay variability of < 10%. By using the radioimmunoassay, it was found that eEF-Tu is a major non-hemoglobin protein of rabbit reticulocyte postribosomal supernatant proteins, comprising about 3% of the total hemoglobin and 10–13% of the non-hemoglobin proteins. Similar results were found for a number of different tissues and cells, including rabbit heart, brain, liver and kidneys, as well as both induced and non induced Friend erythroleukemia cells. Values of eEF-Tu ranged from 1% of supernatant proteins in heart to about 11%, in noninduced erythroleukemic cells. The levels of eEF-Tu in these mammalian tissues were comparable to the level of the homologous factor EF-Tu in Escherichia coli. It has previously been found that EF-Tu constitutes about 6–8% of the supernatant proteins of E. coli [Furano, A. V. (1975) Proc. Natl Acad. Sci. USA, 72, 4780–4784]. The level of eEF-Tu in reticulocytes was compared to the abundance of other components of protein synthesis in reticulocytes, such as translocase (eEF-G), tRNA, ribosomes and eIF-2. In all cases eEF-Tu was present in large excess over these other components.
Kinematic and dynamic synthesis of a parallel kinematic high speed drilling machine

Abstract Typically, the term “high speed drilling” is related to spindle capability of high cutting speeds. The suggested high speed drilling machine (HSDM) extends this term to include very fast and accurate point-to-point motions. The new HSDM is composed of a planar parallel mechanism with two linear motors as the inputs. The paper is focused on the kinematic and dynamic synthesis of this parallel kinematic machine (PKM). The kinematic synthesis introduces a new methodology of input motion planning for ideal drilling operation and accurate point-to-point positioning. The dynamic synthesis aims at reducing the input power of the PKM using a spring element.
An experimental study of stress singularities at a sharp corner in a contact problem

The photoelastic method was used to investigate the nature of the local stress field at a sharp corner of a wedge that was compressed against a larger body. Planar wedge specimens made of photoelastic material were compressed against a half plane (larger body) of identical material at various load levels. Several wedge angles were studied. The nature of the singular stress field postulated by linear elastic analysis was verified and the strength of the singularity was obtained by plotting the variation of fringe order as a function of radial distance from the sharp corner on a logarithmic scale. The experimental results were found to be in good agreement with the theoretical predictions. The effect of interface friction and the effect of rounding off the sharp edge are brietly discussed.
Defining normalcy of the somatotropic axis: an attainable goal?

The diagnoses of acromegaly and dwarfism require biochemical confirmation of abnormal GH and IGF-1 concentrations. The same parameters are used for therapeutic decisions, i.e. initiation or termination of particular treatments. Therefore, reliable and epidemiologically and statistically proven criteria of normalcy for GH and IGF-1 are required for these tasks to be accomplished. Despite major progress in all these areas, the definition of what constitutes “normalcy” of the somatotropic axis is still lacking. Using an example of acromegaly, we discuss the contradictions and the uncertainties of the biochemical diagnosis of this disease.
A hierarchical benchmark association problem in missile defense

This paper formulates a benchmark data association problem in a missile defense surveillance problem. The specific problem considered deals with set of sources that provide "event" (track) estimates via a number of communication networks to a Fusion Center (FC) which has to perform data association prior to fusion. A particular feature of the network model is that the information to distinguish among reports from the same source transmitted through different networks is not available at the FC: the track identity (ID) assigned by the source is not passed on, but only a track ID assigned by the network, and the source ID accompany the track. This makes it necessary to detect and eliminate track duplications at the FC among the messages with the same source ID but different network ID. The resulting data, organized into sensor lists, is associated using a likelihood based cost function with one of the several existing multidimensional assignment (MDA) methods. A comparison of the following two association criteria: Mahalanobis distance ("chi-square") and likelihood ratio (LR) is carried out. It is shown that the LR yields significantly superior results. The tracks obtained after association are fused using a Maximum Likelihood approach. An additional complication is that false reports can be also transmitted by the sources. Examples with several launches, sources and networks are presented to illustrate the proposed solution and compare the performances of two assignment algorithms - the Lagrangean relaxation based S-D and the sequential m-best 2-D - on this realistic problem.
Genesis 1 in Jubilees 2

After the full text of Jubilees became available for western scholarly consumption in the mid-nineteenth century, it soon became the object of sundry comparative studies. The earliest estimates of its date placed it in the first century CE (Dillmann, for one), but later R.H. Charles made the classic case for dating the book to the end of the second century BCE.' Whichever of these dates one preferred, it was obvious to all that Jubilees postdated the Hebrew version of Genesis-Exodus and predated the earliest rabbinic and patristic exegetical works. Thus, the book stood at an ancient point in the history of interpreting Genesis-Exodus. It embodied both unique exegetical stands and hermeneutical moves that were familiar from later texts. Unlike most later commentaries, however, Jubilees bills itself, not merely as an explication of the divinely given words to Moses, but as revelation: its words come from the tablets of heaven and are mediated to Moses by an angel of the presence (1:29-2:1). The evidence from Qumran helps us to see how one group considered Jubilees authoritative: not only have remnants of 14 or 15 copies of the book been found there,2 but the Damascus Document certainly cites it as an authority, and 4Q2283 probably does as well. From the point of view of scriptural exegesis, one of the more interesting passages for comparative purposes is the creation account in Jubilees 2. It is obviously based upon Genesis 1-2, but
Gender classification under extended operating conditions

Gender classification is a critical component of a robust image security system. Many techniques exist to perform gender classification using facial features. In contrast, this paper explores gender classification using body features extracted from clothed subjects. Several of the most effective types of features for gender classification identified in literature were implemented and applied to the newly developed Seasonal Weather And Gender (SWAG) dataset. SWAG contains video clips of approximately 2000 samples of human subjects captured over a period of several months. The subjects are wearing casual business attire and outer garments appropriate for the specific weather conditions observed in the Midwest. The results from a series of experiments are presented that compare the classification accuracy of systems that incorporate various types and combinations of features applied to multiple looks at subjects at different image resolutions to determine a baseline performance for gender classification.
Modeling of spray-formed plates using an X-Y moving substrate

A mathematical model, incorporating the thermal component of sticking efficiency (SEt) into the calculation of shape evolution, is formulated to predict the evolution and final geometry of plates. The plates are spray formed using a moving substrate displaced in a two-dimensional (i.e., X-Y) plane. By using this model, the effects of the substrate movement parameters, such as the acceleration, time required to complete a stroke in the reciprocal movement direction (X-axis), and the velocity in the uniform movement direction (Y-axis), on the shapes of the plates are investigated. The processing parameters are evaluated by minimizing the values of the mean-squared (MS) surface roughness. On the basis of the evaluation, the optimal combinations of processing parameters are found.
Acute hibernation and reperfusion of the ischemic heart.

BACKGROUND Recovery from prolonged low-flow ischemia was studied in isolated, isovolumically beating neonatal piglet hearts (n = 11) and compared with controls (n = 5). METHODS AND RESULTS Hearts were perfused with red blood cell-enhanced Krebs-Henseleit buffer with physiological oxygen-carrying capacity. Left ventricular mechanical function was assessed with a fluid-filled balloon. Measurements of peak systolic pressure, pressure-rate product (PRP), and +dP/dtmax were obtained at various filling pressures. Myocardial oxygen delivery and metabolism (MVO2) and lactate uptake were measured at 30-minute intervals. Control data were obtained with coronary flow (CF) set at 2 ml.min-1.g-1. CF was then reduced to 0.2 ml.min-1.g-1 for 2 hours. Thereafter, reperfusion was instituted at control levels. Hearts not subjected to ischemia were studied at identical time intervals. In these, function remained at greater than 80% after more than 3.5 hours of study. Reduction of CF to 10% was accompanied by an abrupt diminution in function (pressure-rate product) and MVO2 to 20% of control and by lactate release. These measures remained constant for the full 2 hours of ischemia. Incremental return of CF caused a lockstep increase in mechanical function and metabolism. At 30 minutes of reperfusion, PRP was 78% of time-matched controls (p = 0.05), and dP/dtmax did not differ. Increasing calcium to 5 mmol/l returned PRP (and dP/dtmax) to preischemia levels. Myocardial ATP and creatine phosphate concentrations were identical in both groups, although glycogen was lower in the ischemic hearts. CONCLUSIONS Acute hibernation is associated with protection of the in vitro heart from prolonged normothermic ischemia. Systolic function was only modestly lower, and velocity (dP/dtmax) did not differ from control hearts. The minimal "stunning" was fully reversible with calcium.
A probabilistic model for recursive factorized image features

Layered representations for object recognition are important due to their increased invariance, biological plausibility, and computational benefits. However, most of existing approaches to hierarchical representations are strictly feedforward, and thus not well able to resolve local ambiguities. We propose a probabilistic model that learns and infers all layers of the hierarchy jointly. Specifically, we suggest a process of recursive probabilistic factorization, and present a novel generative model based on Latent Dirichlet Allocation to this end. The approach is tested on a standard recognition dataset, outperforming existing hierarchical approaches and demonstrating performance on par with current single-feature state-of-the-art models. We demonstrate two important properties of our proposed model: 1) adding an additional layer to the representation increases performance over the flat model; 2) a full Bayesian approach outperforms a feedforward implementation of the model.
Creating Positive Cultural Images: Thoughts for Teaching about American Indians

(1996). Creating Positive Cultural Images: Thoughts for Teaching about American Indians. Childhood Education: Vol. 73, No. 2, pp. 77-82.
Market estimates of worker dislocation costs

Abstract The labor literature has treated job security as an attribute that can be valued in a hedonic wage framework. What the literature has not done is construction of incremental willingness-to-pay measures for job dislocations. We have taken this step, and have compared estimates to accounting estimates.
A Simple “Curve-fit” Method of Calculating Area Under the Terminal Downslope of Indicator Dilution Curves

A simple visual method by which the decay constant of indicator dilution curves can be determined is described. The area under the terminal downslope is calculated from the appropriate decay constant eliminating the need to replot the downslope on semilogarithmic paper. The method saves time and is accurate.
UNESCO, "universal bioethics," and state regulation of health risks: a philosophical critique.

The United Nations Educational, Scientific, and Cultural Organization's (UNESCO) Universal Declaration on Bioethics and Human Rights announces a significant array of welfare entitlement―to personal health and health care, medicine, nutrition, water, improved living conditions, environmentalprotection, and so forth―as well as corresponding governmental duties to provide for such public health measures, though the simple expedient of announcing that such entitlements are "basic human rights. " The Universal Declaration provides no argument for the legitimacy of the sweeping governmental authority, taxation, and regulation to create and impose such "rights. " As this paper explores that some action promotes a purported good, such as "health, " does not thereby make the action morally permissible. Just as there are moral limits on legitimate personal actions, there are also moral limits on legitimate governmental actions to promote purported goods, including health. A core question of any governmental regulation, therefore, is whether it is a legitimate application of moral political authority or an unauthor- ized act of state coercion. Pace UNESCO's wide-ranging assertions, this paper argues that promoting health only falls within the legitimate authority of governments in very narrowly defined circumstances. As the paper critically explores, at stake are foundational moral and political questions concerning the limits of governmental authority to intervene in the consensual interaction of persons. Imposing such duties on others, including citizens of a state through regulatory activity and taxation, must be justified, nonarbitrary, and demonstrably within the limits of moral political authority. UNESCO's assertions do not meet this burden of proof.
The effect of various concentrations of tocopherols and tocopherol mixtures on the oxidative stability of a sample of lard.

A comparison was made of α-, γ-, and δ-tocopherol at various concentrations and a mixture of these tocopherols representing the average tocopherol content of peanut oil on the oxidative stability of lard at 97C. Uptake of oxygen was used to indicate the length of the induction period. The antioxidant effectiveness of the tocopherols was found to increase in the order α, δ, γ. The antioxidant efficiency decreases with increasing concentrations of tocopherols such that addition of any single tocopherol above a concentration of 250 µg/g has little effect on oxidative stability. A mixture equivalent to that of an average peanut oil sample, containing 150 µg/g of α-tocopherol and 250 µg/g of γ-tocopherol and 15 µg/g of δ-tocopherol was found to be no more stable than one containing 250 µg/g of γ-tocopherol alone.
A threat to the public health workforce: evidence from trends in preventive medicine certification and training

Evidence of a growing need for preventive medicine specialists is the congruence between needed competencies for practice in the current health care environment, as identified by the Council on Graduate Medical Education (COGME) and in other national reports, and the core competencies of preventive medicine residents. The total number of certified specialists in preventive medicine is 6091. The proportion of self-designated preventive medicine specialists among all U.S. physicians is on the decline and the greatest decline has been among those in public health (PH) and general preventive medicine (GPM). In addition, the total number of preventive medicine residents is on the decline, and the decline has been greatest among those training in PH and combined PH/GPM. One of the reasons for this decline has been inadequate funding due to the absence of Medicare graduate medical education (GME) financing for population-based vs. individual patient care services and meager and diminishing Title VII support. A paucity of faculty is apparent in medical schools with residency training and board certification in preventive medicine. Several actions may help reverse this trend and assure adequate numbers of preventive medicine specialists: expansion of Title VII to increase the number of residents receiving stipends and tuition, adding infrastructure support for faculty development and funding of demonstration projects in distance learning and in joint generalist/ preventive medicine residency training. Medicare GME reform should include recognition of population-based services and inclusion of preventive medicine residencies in provisions for "nonhospital-based" training and in up-weighting methodologies for primary care training. Expansion of Veterans Affairs, National Institute for Occupational Safety and Health, and Department of Defense support is also needed as is attention to resident debt reduction.
Three-dimensional Super-resolution Fluorescence Microscopy and Its Application to Clathrin Mediated Endocytosis

The recent invention of super-resolution fluorescence microscopy allows nanoscopic investigation of cellular structures. Among these techniques, the Stochastic Optical Reconstruction Microscopy (STORM) is based on precise single molecule localization of photoswitchable fluorescent probes. By stochastically activating, imaging and deactivating subsets of fluorophores, it makes their images optically resolvable and determines their positions with nanometer precision. A super-resolution image is then reconstructed using these localizations. We now extend this approach to three-dimensional (3D) microscopy by determining the 3D coordinates of activated probes through astigmatism imaging: a cylindrical lens is inserted into the imaging optical path such that the image of individual molecules appear elliptical with the ellipticity depending on its z-position. Using this approach, we have achieved an optical resolution of 20-30 nm in the x-y direction and 50-60 nm in the z direction, representing an order of magnitude improvement over conventional fluorescence microscopy in all three dimensions. We have resolved the nanoscopic morphology of cellular structures that was previously deemed impossible by light microscopy.As a specific application, we use STORM to study the mechanism of clathrin mediated endocytosis in an in vitro reconstituted system. Proteins of interest in this system are directly labeled with photoswitchable fluorescent probes. This procedure is facilitated by covalently linking the two components of the probe, an activator dye and a photoswitchable reporter fluorophore, to form a single chemical unit prior to protein labeling. Using multicolor 3D STORM, we have characterized the spatial organization of plasma membrane, clathrin, actin and tubule forming proteins dynamin at the site of clathrin mediated endocytosis. These results reveal the molecular architecture of the nascent clathrin-coated pits at the nanometer scale and help to establish the role of actin and dynamin in membrane invagination, scission and vesicle formation.
Accommodation in the workplace

Abstract With the passage of the Americans with Disabilities Act, employers are now required to provide reasonable accommodations for qualified individuals with disabilities. Although the practice of accommodating applicants or employees is not new, accommodation for disabled individuals has shifted the thinking about accommodation and our perceptions and reactions to such practices. In this article, four major factors that contribute to workplace reactions to accommodation are discussed: (1) rationale for the accommodation, (2) the nature of the accommodation, (3) whether the accommodation is organization, employee or jointly initiated, and (4) the characteristics of the target or person being accommodated. A general framework is presented depicting how these variables combine to influence workplace reactions to accommodation. Research from managerial, social psychological and rehabilitation literatures is reviewed and integrated.
Modulation of somatosensory event-related potential components in a tactile–visual cross-modal task

Human tactile discrimination studies have shown that visual stimuli enhance tactile performance. Other studies on event-related potentials showed that somatosensory N140 was enhanced when attention of human subjects was directed to tactile stimuli. Therefore, we hypothesized that N140 would be modulated when human subjects performed tactile cross-modal delay tasks. Scalp-event-related potentials were recorded from normal subjects performing either a tactile-tactile unimodal, or a tactile-visual cross-modal delayed matching-to-sample task. Identical tactile stimuli were used in both tasks. N140 component evoked by the tactile stimuli was enhanced in the cross-modal task. Enhancement of this component was also observed in control cross-modal tasks. The results suggest that tactile-visual cross-modal association affects tactile sensory-perceptual processes in humans.
Material contrast identification and compositional contrast mapping using backscattered electron imaging

Scanning Electron Microscopy (SEM) is a vital high magnification and high resolution inspection tool in failure analysis of semiconductor devices. It provides an image of a sample by scanning the sample surface with a high-energy beam of electrons in a raster scan pattern. The electrons interact with the atoms that make up the sample producing different signals that contain information about the sample's surface topography and composition. Interaction of an accelerated electron beam with a sample target produces a variety of elastic and inelastic collisions between electrons and atoms within the sample. The signal produced by the elastic collisions is the backscattered electrons (BSE). BSE imaging is used to differentiate contrasts in a material comprising of different chemical compositions. It can locate regions of different atomic number and high atomic number impurities. It is also very helpful for obtaining high resolution compositional maps of a sample and for quickly distinguishing different material phases. This paper shows the importance of BSE imaging as one of the exemplary scanning electron microscopy technique in failure analysis of semiconductor devices. Fundamentals and concepts behind this technique are also discussed. Case studies show how BSE imaging played a vital role in giving more material information leading to the understanding of the real phenomenon behind the observed failures or material interactions.
Function of Yeast Rad52 Protein as a Mediator between Replication Protein A and the Rad51 Recombinase

The RAD51 and RAD52 genes of Saccharomyces cerevisiae are key members of the RAD52 epistasis group required for genetic recombination and the repair of DNA double-stranded breaks. The RAD51 encoded product mediates the DNA strand exchange reaction. Efficient strand exchange is contingent upon the addition of the heterotrimeric single-stranded DNA binding factor replication protein A (RPA) after Rad51 has nucleated onto the single-stranded DNA. However, if the single-stranded DNA is incubated with Rad51 and RPA simultaneously to mimic what may be expected to occur in vivo, the efficiency of strand exchange decreases dramatically, revealing an inhibitory effect of RPA that is distinct from its stimulatory function. Interestingly, the inclusion of Rad52 protein, which has been purified in this study from yeast cells, restores the efficiency of strand exchange. Thus, Rad52 functions as a co-factor for the Rad51 recombinase, acting specifically to overcome the apparent competition by RPA for binding to single-stranded DNA.
Pneumocystis carinii dihydrofolate reductase used to screen potential antipneumocystis drugs.

Abstract Pneumocystis carinii was obtained in high yield from the lungs of immunosuppressed rats by rupturing mammalian host cells, washing away the soluble mammalian dihydrofolate reductase, and harvesting intact organisms in association with the mammalian plasma membranes. P. carinii dihydrofolate reductase, measured in the 100,000 x g supernatant from sonicated organisms, was obtained in yields ranging up to 62 IU per rat. The enzyme prepared in the presence of protease inhibitors was stable when frozen in liquid nitrogen. P. carinii dihydrofolate reductase differed from the mammalian enzyme in that the former was slightly inhibited by 150 mM KCl, whereas the latter was stimulated over twofold by 150 mM KCl. The standard assay for P. carinii dihydrofolate reductase contained 0.12 mM NADPH and 92 microM dihydrofolic acid. Under these conditions, the 50% inhibitory concentrations of the known inhibitors trimethoprim, trimetrexate, and pyrimethamine were 12 microM, 42 nM, and 3.8 microM, respectively. These standard compounds were also tested against dihydrofolate reductase from rat liver to allow an assessment of the selectivity of the drugs. Although it was the least potent, trimethoprim was the most selective. Pyrimethamine was more potent but was nonselective. Trimetrexate was extremely potent but was selective for mammalian dihydrofolate reductase. A series of experimental compounds was obtained from the National Cancer Institute and other sources through the Developmental Therapeutics Branch of the Division of AIDS at the National Institute of Allergy and Infectious Diseases. Among the first 87 compounds tested, 11 had 50% inhibitory concentrations below that of trimetrexate and 3 were more selective than trimethoprim. The most promising compounds in this original group were chemically related to methotrexate.
Testosterone attenuates β-amyloid toxicity in cultured hippocampal neurons

Abstract Accumulating evidence suggests that testosterone has neurotrophic and perhaps neuroprotective actions. Thus, age-related depletion of testosterone may increase the brain’s vulnerability to Alzheimer’s disease and related disorders. To begin investigating this issue, cultured neurons were exposed to the Alzheimer-related insult β-amyloid in the presence of testosterone. β-Amyloid neurotoxicity was significantly reduced by testosterone via a rapid, estrogen-independent mechanism. These data may provide additional insight into the treatment of age-related neurodegenerative disorders.
Comparative knowledge and practice of emergency physicians, cardiologists, and primary care practitioners regarding drug therapy for acute myocardial infarction.

Objectives This study assesses the knowledge and practice of emergency physicians regarding the treatment of acute myocardial infarction (AMI) and compares the results with previously published data on cardiologists and primary care practitioners. Background Debate surrounding the respective roles of emergency physicians, primary care practitioners, and specialists figures prominently in discussions regarding the nation's evolving health-care system. Data are lacking about the comparative knowledge and practice of emergency physicians, cardiologists, and primary care practitioners regarding conditions commonly treated by all three groups, eg, AMI. Methods A survey of 1,045 emergency physicians, nationally, was conducted in 1995 regarding five short-term pharmacologic interventions employed for many years in the standard treatment of AMI. The emergency physicians were questioned about the effect on survival of each intervention and the likelihood that they would prescribe each intervention. The findings were then compared with previously published data on the knowledge and practice of cardiologists and primary care practitioners obtained in New York and Texas in 1993. Identical clinical queries and eligibility criteria were employed in all groups. Results The responding emergency physicians' knowledge was similar or significantly greater than that of responding cardiologists for the effect on survival of most of the short-term interventions, and their practice patterns were similar or significantly better than responding cardiologists for all interventions studied. Emergency physicians and cardiologists had significantly better knowledge and practice in this area compared with responding primary care practitioners. Conclusions For the management of AMI, emergency physicians, on average, have a similar or greater awareness of the effects on survival and similar or better practice patterns regarding most acute pharmacologic interventions when compared with those of cardiologists; both groups, on average, have a superior knowledge and practice when compared with primary care practitioners. These results illustrate the importance of emergency medicine and support further consideration of an expanding role for the emergency physician in the nation's evolving health-care system.
Left ventricular performance in patients with coexistent mitral stenosis and aortic insufficiency

Isolated mitral stenosis and isolated aortic insufficiency impose unique and opposite loading conditions on the left ventricle. To assess these combined effects, hemodynamic and angiographic factors were compared among normal subjects and patients with isolated mitral stenosis, isolated aortic insufficiency or combined mitral stenosis and aortic insufficiency. Left ventricular end-diastolic volume index was lower in patients with combined lesions and severe or moderate aortic insufficiency than in patients with isolated severe or moderate aortic insufficiency (138 ± 19 versus 206 ± 20 cc/m 2 and 87 ± 5 versus 145 ± 22 cc/m 2 , respectively) (p Among patients with moderate or severe aortic insufficiency, 8 of 14 with isolated insufficiency had a reduced ejection fraction or circumferential fiber shortening rate compared with 5 of the 9 patients with combined lesions. Among patients with isolated aortic insufficiency, left ventricular end-systolic wall stress and end-diastolic and end-systolic volume indexes were higher (p The contractile index (ratio of end-systolic wall stress to end-systolic volume index) was significantly depressed in patients with severe aortic insufficiency in the groups with isolated aortic insufficiency or combined lesions. Among patients with moderate or severe aortic insufficiency, 7 of 14 of those with an isolated lesion and 5 of 9 with combined lesions had a lower than normal linear end-systolic wall stress/fractional shortening relation. It is concluded that: 1) mitral stenosis reduces the left ventricular volume overload of aortic insufficiency when these lesions coexist; 2) elevated left ventricular wall stress, excessive left ventricular dilation and reduced shortening characterize patients with aortic insufficiency and low ejection performance, but not patients with combined mitral stenosis and aortic insufficiency and low ejection performance, despite significant aortic insufficiency; and 3) the status of left ventricular systolic muscle function in patients with combined lesions is not entirely clear, but may involve a functional spectrum between isolated mitral stenosis and isolated aortic insufficiency.
Sxratch for Metasaxophone

Sxratch (2006) is a musical composition and interactive performance work created for the Metasaxophone, an augmented instrument invented and built by the author in 1999. The Metasaxophone is one of the earliest augmented instruments still in regular use today. The piece uses the instrument interface to control interactive computer sound software and robots.
Anodic Electrochemistry of Multiferrocenyl Phosphine and Phosphine Chalcogenide Complexes in Weakly Nucleophilic Electrolytes

The anodic electrochemistry of several compounds containing two or three ferrocenyl moieties linked by a phosphine or phosphine chalcogenide group has been studied in dichloromethane containing [NBu4][TFAB], where TFAB is the tetrakis(perfluoroaryl)borate anion, [B(C6F5)4]-. In two cases, namely [CpFe(C5H4)]3P (3) and [CpFe(C5H4)]2PO(Ph) (6), the first one-electron-oxidation product is stable on the cyclic voltammetric (CV) time scale and subsequent oxidations at more positive potentials are also observed. The oxidations of [CpFe(C5H4)]2PPh (2) and [CpFe(C5H4)]3PSe (7) are not reversible, and their monocations undergo follow-up reactions that are first-order and second-order, respectively, in the neutral compound. The results are consistent with a model in which the initial oxidation always involves a largely ferrocenyl-based HOMO which, nevertheless, has significant phosphine or phosphine chalcogenide character, allowing radical-type reactions, including dimerizations, at the linking group. The tradition...
An automated method for ATP analysis utilizing the luciferin-luciferase reaction.

Abstract An automated method for the analysis of ATP has been described. This method uses the luciferin-luciferase reaction, with the firefly extract being delivered by means of an automatic pipetter interfaced with an automatic liquid scintillation spectrometer. A range of 10–300 pmoles is obtained with a standard deviation of 5·10%. An analysis rate of approximately 200 samples per hr can be attained. At least 1400 samples can be run from one standard curve when the firefly extract is stabilized with bovine serum albumin and mercaptoethanol.
Renal Osteodystrophy and Aging

The bone disease seen in our aging dialysis population is a complex mixture of osteoporosis and renal osteodystrophy. Attention must be paid to both of these issues. Hip fractures are increased with aging and this increase is further aggravated by renal failure. Preventive management with Vitamin D and bisphosphonates is reviewed.
Effect of carbohydrate ingestion and hormonal responses on ratings of perceived exertion during prolonged cycling and running.

This randomized, double-blind, placebo-controlled study was designed to determine the influence of exercise mode, and 6% carbohydrate (C) versus placebo (P) beverage ingestion, on ratings of perceived exertion (RPE) and hormonal regulation to 2.5 h of high-intensity running and cycling (≈75% maximum oxygen uptake) by ten triathletes who acted as their own controls. Statistical significance was set at P ≤ 0.05. The pattern of change in RPE over time was significantly different between C and P ingestion (P < 0.001) and between running and cycling modes (P = 0.001). The lowest RPE values were seen in the C-cycling sessions and the highest in the P-running sessions. The pattern of change in the respiratory exchange ratio and fat and carbohydrate oxidation rates were significantly different between the C and P conditions but not between the running and cycling modes. C relative to P ingestion (but not exercise mode) was associated with higher plasma levels of glucose and insulin and lower plasma cortisol and growth hormone levels. The pattern of change in plasma levels of catecholamines and lactate did not differ between the C and P conditions. These data indicate that a lower RPE was associated with a higher level of carbohydrate oxidation, higher plasma glucose and insulin levels, and lower plasma cortisol and growth hormone levels during cycle exercise following C supplementation as compared to P feeding. These findings support a physiological link between RPE and carbohydrate substrate availability as well as selected hormonal regulation during cycle exercise.
Regulation of the cell cycle during early Xenopus development

Maturation-promoting factor (MPF) is a partially purified M-phase-specific activity that induces meiosis in frog oocytes and is detectable in mitotic lysates from cells of wide phylogenetic origins. We show here that without protein synthesis, addition and removal of MPF can drive the mitotic cycle in frog eggs, including nuclear membrane breakdown and reformation, chromosome condensation and decondensation, and suppression and initiation of DNA replication on endogenous DNA and on injected plasmid templates. We have also studied M-phase arrest induced by injection of unfertilized egg cytoplasm and show that this arrest blocks an endogenous cytoplasmic cell-cycle oscillator and causes the stabilization of MPF activity. The oscillator can be restarted by injection of Ca++, which causes chromosome decondensation, reinitiation of DNA replication, and loss of MPF activity. We have looked in more detail at how DNA replication responds to the level of MPF and show that the effects are on the chromatin template and not the replication machinery. These results suggest that in Xenopus embryos cell-cycle events of the nucleus, including DNA replication and mitosis, are controlled by the level of MPF activity, which is driven by or may be part of an autonomous cell-cycle oscillator. The way in which a more complicated somatic cell cycle may arise from the simple embryonic cell cycle is discussed.
Early Paleoindian big-game hunting in North America: Provisioning or Politics?

We question several common elements of conventional descriptions of Early Paleoindian adaptations. Specifically, we examine the presumed scales of residential mobility, the role of high-quality lithics in these movements, and the extent to which First Americans hunted large game as a fundamental part of their food-getting activities. We compare the Early Paleoindian data to relevant information on hunting, mobility, and weaponry documented ethnohistorically and ethnographically. We then construct an alternative explanation for the Early Paleoindian record based on the premise that the hunting of large mammals, presumably by men, may have been motivated more by social and political factors than by the need to regularly and reliably provision a family or band with food. By proposing a plausible alternative explanation for the available data, we suggest that there is good reason to think critically about several of the basic components of the conventional view of Early Paleoindian adaptations.
Aztreonam therapy for gram-negative pneumonia

Nineteen patients with community- or hospital-acquired gram-negative pneumonia were treated with aztreonam. Other gram-negative antibiotics were withheld. Thirteen patients (68 percent) had clinical cures and 15 (79 percent) had microbiologic cures with aztreonam. No adverse reactions or drug toxicity occurred in this population.