cssi/SciSciGPT-SciSciNet huggingface dataset:
Asperity-asperity contact mechanisms simulated by a two-ball collision apparatus

Abstract Wear of materials is controlled by asperity-asperity contacts. Since the asperities are of uneven height, the stresses imposed by different pairs of asperities necessarily are unequal. When two surfaces come together, there is a distribution of the contact stresses. In a wear experiment, we measure wear by measuring the cumulative wear across the interface from the beginning of the experiment, and we measure friction by measuring the average friction of all the asperity contacts across the interface at the particular instance in time. The friction and wear characteristics at the asperity level have interested the tribology community for a long time. Data at the level, however, are difficult to obtain and the conditions that lead to a single asperity wear event are not understood. This paper describes the design and construction of a two-ball collision test apparatus to simulate asperity contacts. Materials used include steels brass, and aluminum of different hardness and elasticity. Dynamic friction and wear of the collision were measured under dry, paraffin oil lubricated conditions. The results suggested that at a coefficient of 0.4, wear of the asperity contact occurred. A simple plain strain model confirmed the observations that under certain conditions, asperity wear should occur at a coefficient of 0.39.
INTERACTION OF IONIZING AND VISIBLE RADIATION IN MUTATION INDUCTION IN NEUROSPORA CRASSA

Conidia of the purple adenineless strain of N. crassa were irradiated with 25 kr of x rays and then exposed to far-red or red radiations or to far-red followed by red radiation. Far-red light, without effect on unirradiated conidia, augmented the genetic damage caused by x rays as measured by survival (colony count), back mutation to adenine prototrophy, and the induction of mutants affecting colony morphology. Post-x-irradiation with red light ameliorated the severity of x radiation as measured by survival and back mutation. The potentiation of x-ray-induced genetic damage by far-red light could be completely negated by subsequent exposure to red light.
SNP discovery in wild and domesticated populations of blue catfish, Ictalurus furcatus, using genotyping-by-sequencing and subsequent SNP validation

Blue catfish, Ictalurus furcatus, are valued in the United States as a trophy fishery for their capacity to reach large sizes, sometimes exceeding 45 kg. Additionally, blue catfish × channel catfish (I. punctatus) hybrid food fish production has recently increased the demand for blue catfish broodstock. However, there has been little study of the genetic impacts and interaction of farmed, introduced and stocked populations of blue catfish. We utilized genotyping-by-sequencing (GBS) to capture and genotype SNP markers on 190 individuals from five wild and domesticated populations (Mississippi River, Missouri, D&B, Rio Grande and Texas). Stringent filtering of SNP-calling parameters resulted in 4275 SNP loci represented across all five populations. Population genetics and structure analyses revealed potential shared ancestry and admixture between populations. We utilized the Sequenom MassARRAY to validate two multiplex panels of SNPs selected from the GBS data. Selection criteria included SNPs shared between populations, SNPs specific to populations, number of reads per individual and number of individuals genotyped by GBS. Putative SNPs were validated in the discovery population and in two additional populations not used in the GBS analysis. A total of 64 SNPs were genotyped successfully in 191 individuals from nine populations. Our results should guide the development of highly informative, flexible genotyping multiplexes for blue catfish from the larger GBS SNP set as well as provide an example of a rapid, low-cost approach to generate and genotype informative marker loci in aquatic species with minimal previous genetic information.
Technique of ultrasonic detection and mapping of abdominal wall adhesions

A technique for noninvasive ultrasound examination to detect and map abdominal wall adhesions is described. The examination is based on the demonstration of movement of abdominal viscera during real-time imaging. This movement is called viscera slide and either occurs spontaneously as a result of respiratory movement or may be induced by manual compression. Abdominal wall adhesions produce a restriction of viscera slide. Ultrasonic demonstration of restricted viscera slide has been used for the precise localization and mapping of abdominal wall adhesions prior to abdominal surgery. The technique may be particularly useful in providing safe initial access in patients undergoing laparoscopy who are at increased risk for trocar injury of viscera due to abdominal wall adhesions resulting from previous surgery or peritonitis.
Fluorescence polarization values of amniotic fluid collected from the vagina after rupture of the membranes

Transvaginal collection of amniotic fluid and the use of a reliable test for fetal lung maturity will provide information needed in the management of patients with premature rupture of the membranes.
PDGF is Required for Remyelination-Promoting IgM Stimulation of Oligodendrocyte Progenitor Cell Proliferation

Background Promotion of remyelination is a major goal in treating demyelinating diseases such as multiple sclerosis (MS). The recombinant human monoclonal IgM, rHIgM22, targets myelin and oligodendrocytes (OLs) and promotes remyelination in animal models of MS. It is unclear whether rHIgM22-mediated stimulation of lesion repair is due to promotion of oligodendrocyte progenitor cell (OPC) proliferation and survival, OPC differentiation into myelinating OLs or protection of mature OLs. It is also unknown whether astrocytes or microglia play a functional role in IgM-mediated lesion repair. Methods We assessed the effect of rHIgM22 on cell proliferation in mixed CNS glial and OPC cultures by tritiated-thymidine uptake and by double-label immunocytochemistry using the proliferation marker, Ki-67. Antibody-mediated signaling events, OPC differentiation and OPC survival were investigated and quantified by Western blots. Results rHIgM22 stimulates OPC proliferation in mixed glial cultures but not in purified OPCs. There is no proliferative response in astrocytes or microglia. rHIgM22 activates PDGFαR in OPCs in mixed glial cultures. Blocking PDGFR-kinase inhibits rHIgM22-mediated OPC proliferation in mixed glia. We confirm in isolated OPCs that rHIgM22-mediated anti-apoptotic signaling and inhibition of OPC differentiation requires PDGF and FGF-2. We observed no IgM-mediated effect in mature OLs in the absence of PDGF and FGF-2. Conclusion Stimulation of OPC proliferation by rHIgM22 depends on co-stimulatory astrocytic and/or microglial factors. We demonstrate that rHIgM22-mediated activation of PDGFαR is required for stimulation of OPC proliferation. We propose that rHIgM22 lowers the PDGF threshold required for OPC proliferation and protection, which can result in remyelination of CNS lesions.
Comparison of flow microdynamics for a continuous granular mixer with predictions from periodic slice DEM simulations

Abstract Using periodic slice discrete element method (DEM) simulations to model sections of a full continuous blender offers significant savings in computation cost. Before development of a periodic slice based continuous mixer model, the accuracy of periodic slice models for predicting full blender behavior needs to be examined. Flow microdynamics obtained from periodic slice simulations are compared against full blender results by examining speed and velocity frequency distributions. The periodic slice models are found to replicate full blender flow microdynamics well for central sections of the full blender. Reasonably good agreement is obtained for the inlet and outlet regions where the periodic boundary assumption is less valid. Results suggest that the use of periodic slice simulations to represent full blender behavior is a feasible approach which may be extended in the future to develop a full blender model. A small change in particle size is observed to have a negligible effect on the fill level of the continuous mixer, suggesting that larger particles may be used in DEM simulations to predict bulk flow quantities.
A re-examination of the structure of unemployment

This paper examines whether there has been a structural change in the sensitivity of unemployment to the business cycle in the United States. The analytical framework of the investigation rests on two functional relationship between unemployment and economic activity introduced by Thurow (1965). The results are conclusive in suggesting that there has been no change in this sensitivity over the period 1948–88 (QI). Thus, both total unemployment and various categories (including sex, race, age and industry) of unemployment are as sensitive to variations in the level of economic activity today as they were three decades ago.
Atopic allergy: asthma and atopic dermatitis

During the past 2 years much progress has been made in our understanding of allergic diseases: there is now increasing evidence for a direct causal relationship between exposure to allergen and the chronic diseases, asthma and atopic dermatitis; furthermore, it seems very likely that exposure to indoor allergens is the most common cause of the inflammation of the lungs that is characteristic of asthma.
A simple technique for screening near-field probes

Abstract In near-field microscopy, probe quality usually limits the microscope's resolution and sensitivity. Although examining the probe in an electron microscope and imaging a test pattern with the probe in a near-field microscope provide detailed information about probe quality, both techniques are time consuming, often requiring that the probe be coated with metal. A qualitative technique is presented for rapidly screening fiber tapers for defects by examining their diffraction patterns.
Suicide risk management for the sequenced treatment alternatives to relieve depression study: Applied NIMH guidelines

NIMH guidelines to manage subjects who are suicidal during their participation in clinical trials include a full range of procedures to minimize suicidal risk, yet no reports to date have shown how researchers should best implement these guidelines. The architects of the sequenced treatment alternatives to relieve depression (STAR*D) study operationalized and implemented the NIMH guidelines by developing a comprehensive set of procedures to detect, monitor, and manage suicidal subjects during a large, complex, multisite clinical trial. Because of the large size of the study (anticipated n = 4000), the wide geographic distribution, the large number of treating STAR*D clinicians, the broad array of subjects with psychiatric and medical comorbidities, and the focus on treatment-resistant depression, along with the complexity of multiple treatment steps and randomization points in STAR*D, the risk of suicide, safety monitoring of suicidal subjects presented a unique challenge. This paper describes methods derived from the NIMH guidelines used to manage suicidal risk in STAR*D including the use of an interactive voice response system to alert clinicians, regional center directors, and safety officers.
Fair Trade: Social Regulation in Global Food Markets.

Abstract This article analyzes the theoretical and empirical parameters of social regulation in contemporary global food markets, focusing on the rapidly expanding Fair Trade initiative. Fair Trade seeks to transform North/South relations by fostering ethical consumption, producer empowerment, and certified commodity sales. This initiative joins an array of labor and environmental standard and certification systems which are often conceptualized as “private regulations” since they depend on the voluntary participation of firms. I argue that these new institutional arrangements are better understood as “social regulations” since they operate beyond the traditional bounds of private and public (corporate and state) domains and are animated by individual and collective actors. In the case of Fair Trade, I illuminate how relational and civic values are embedded in economic practices and institutions and how new quality assessments are promoted as much by social movement groups and loosely aligned consumers and producers as they are by market forces. This initiative's recent commercial success has deepened price competition and buyer control and eroded its traditional peasant base, yet it has simultaneously created new openings for progressive politics. The study reveals the complex and contested nature of social regulation in the global food market as movement efforts move beyond critique to institution building.
Organizational and individual determinants of patent production of academic scientists and engineers in the United States

This is a copy of an article accepted for publication in Science and Public Policy. The definitive publisher-authenticated version Huang WL, Feeney MK, Welch EW. Organizational and individual determinants of patent production of academic scientists and engineers in the United States. Science and Public Policy. 2011;38(6):463-479. is available online at:http://www.ingentaconnect.com/content/oup/spp
A Cautionary Tale About Cautionary Tales About Intervention

Expressions of discomfort or concern with interventions by radical social science movements, such as Critical Management Studies (CMS) or Science and Technology Studies (STS) in public controversies have rested heavily on two concerns: first, that radical social science is not useful to institutions like business and, second, that, in order to make themselves useful such interventions must compromise the radicalism of the social science program. A third concern has been that intervention is not the job of the social scientist. Recently, my and others' interpretations of my own intervention in law in one case have become something of an object lesson in the perils and pitfalls posed by legal interventions by STS scholars. This paper presents a more optimistic interpretation of my intervention experiences in fingerprint cases based on a broader array of experience than that single case. I suggest, first, that we may need to think more carefully about how to measure the utility of critical social science int...
Triglyceride and cholesterol ester metabolism of rat 1 cells and Rous Sarcoma Virus-transformed rat 1 cells☆

Abstract The incorporation of 14 C-long-chain fatty acids into the neutral lipids of rat 1 cells and B77 Rous Sarcoma Virus-transformed rat 1 cells was compared. Increased labeling of the cholesterol ester and triglyceride fractions was observed in the transformed cells. In temperature shift experiments, using B77 ts src Rous Sarcoma Virus-transformed rat 1 cells, alterations of cholesterol esterification could first be detected 4–6 h after shift to the permissive temperature. Changes in triglyceride metabolism could be shown as early as 4–6 h after activation of the transforming gene function. It is concluded that alterations of neutral lipid metabolism are among the early effects of the transformation process.
Proton‐Ionizable crown compounds. 7. Synthesis of new crown compounds containing the dialkylhydrogenphosphate moiety

A new series of macrocyclic ligands containing the dialkylhydrogenphosphate moiety is reported. These compounds were prepared by reacting phosphorus oxychloride with the appropriate oligoethylene glycol followed by a hydrolysis step. One of these new macrocyclic compounds transported the alkali metal cations as well as lead, zinc and silver ions.
On the Asymptotic Performance of Multi-Dwell Signal Acquisition in Dense Multipath Channels

This paper investigates the mean acquisition time (MAT) of an acquisition system that employs an optimal multi-dwell detector at the detection layer. We derive lower bound and upper bound expressions for the cases when the search layer employs the optimal search procedure and the conventional serial search. The bounds depend only on a few parameters at the detection layer and can be used for the design and analysis of a broad class of multi-dwell detectors. The results indicate that in a high signal-to-noise ratio (SNR) regime, an intelligent search procedure improves the MAT of the conventional serial search by approximately Nhit times, where Nhit is proportional to the number of propagation paths. On the other hand, for a low SNR regime, only moderate improvement can be obtained. The results in this paper are valid for any fading statistic
PhEDEx Data Service

The PhEDEx Data Service provides access to information from the central PhEDEx database, as well as certificate-authenticated managerial operations such as requesting the transfer or deletion of data. The Data Service is integrated with the "SiteDB" service for fine-grained access control, providing a safe and secure environment for operations. A plug-in architecture allows server-side modules to be developed rapidly and easily by anyone familiar with the schema, and can automatically return the data in a variety of formats for use by dierent client technologies. Using HTTP access via the Data Service instead of direct database connections makes it possible to build monitoring web-pages with complex drill-down operations, suitable for debugging or presentation from many aspects. This will form the basis of the new PhEDEx website in the near future, as well as providing access to PhEDEx information and certificate-authenticated services for other CMS dataflow and workflow management tools such as CRAB, WMCore, DBS and the dashboard. A PhEDEx command-line client tool provides one-stop access to all the functions of the PhEDEx Data Service interactively, for use in simple scripts that do not access the service directly. The client tool provides certificate-authenticated access to managerial functions, so all the functions of the PhEDEx Data Service are available to it. The tool can be expanded by plug-ins which can combine or extend the client-side manipulation of data from the Data Service, providing a powerful environment for manipulating data within PhEDEx.
Diets high in selenium and isoflavones decrease androgen-regulated gene expression in healthy rat dorsolateral prostate

Background High dietary intake of selenium or soybean isoflavones reduces prostate cancer risk. These components each affect androgen-regulated gene expression. The objective of this work was to determine the combined effects of selenium and isoflavones on androgen-regulated gene expression in rat prostate.
Dickens and goodbye

A short meditation on the theme of parting or saying goodbye in Dickens’s novels and Prefaces.
Optimal source-based rerouting for self-healing networks

This paper proposes an optimal searching method of source-based rerouting for a virtual circuit network to realize highly reliable self-healing networks. The topology of the networks is assumed to be arbitrary while providing a pair of disjoint paths between two termination nodes. The high-reliability is accomplished by establishing a pre-established protection path in addition to its working path, and switching to the protection path at the termination nodes as soon as a failure is detected in a network component along the working path.
Development and improvement of compressor performance prognostics for US Navy gas turbine engines

In December 2003, Naval Surface Warfare Center Gas Turbine Emerging Technologies section conducted land-based fouling testing on a Rolls Royce/Allison 501-K17 gas turbine engine. The purpose of this testing was to collect data to improve a previously developed compressor health prognostics algorithm. For the purpose of Phase I of this testing, fouling was accomplished by injecting salt into the gas turbine inlet air stream. Phase II of this testing will consist of fouling the middle and back regions of the compressor. Influence coefficients can then be developed for each of these regions indicating how a given region affects overall performance. Typically, in a marine environment, fouling of the front stages occurs due to ingested salt while fouling in middle and rear regions occurs from a combination of ingested salt and oil seal leakage. In order to monitor engine performance, it was necessary to add several sensors to the existing test cell. In addition, hardware was added to both ingest and monitor the concentration of salt in gas turbine inlet air. Preliminary results from Phase I indicate that front stage compressor fouling causes a clear increase in inlet static pressure. This is due to the mass flow restriction through the compressor. Additional results are currently being summarized and data is being utilized to improve the 501-K17 compressor performance algorithm previously noted
Combined Effects of Compact Development, Transportation Investments, and Road User Pricing on Vehicle Miles Traveled in Urbanized Areas

Vehicle miles traveled (VMT) is the primary determinant of traffic congestion, vehicle crashes, greenhouse gas emissions, and other effects of transportation. Two previous studies have sought to explain VMT levels in urbanized areas. This study updates and expands on previous work with more recent data, additional metrics, and structural equation modeling (SEM) to explain VMT levels in 315 urbanized areas. According to SEM, population, income, and gasoline prices are primary exogenous drivers of VMT. Development density is a primary endogenous driver. Urbanized areas with more freeway capacity are significantly less dense and have significantly higher VMT per capita. Areas with more transit service coverage and service frequency have higher development densities and per capita transit use, which leads to lower VMT per capita. The indirect effect of transit on VMT through land use, the so-called land use multiplier, is more than three times greater than the direct effect through transit ridership.
Intuitive and axiomatic arguments for quantifying diagnostic test performance in units of information.

Objectives: Mutual information is a fundamental concept of information theory that quantifies the expected value of the amount of information that diagnostic testing provides about a patient’s disease state. The purpose of this report is to provide both intuitive and axiomatic descriptions of mutual information and, thereby, promote the use of this statistic as a measure of diagnostic test performance. Methods: We derive the mathematical expression for mutual information from the intuitive assumption that diagnostic information is the average amount that diagnostic testing reduces our surprise upon ultimately learning a patient’s diagnosis. This concept is formalized by defining “surprise” as the surprisal, a function that quantifies the unlikelihood of an event. Mutual information is also shown to be the only function that conforms to a set of axioms which are reasonable requirements of a measure of diagnostic information. These axioms are related to the axioms of information theory used to derive the expression for entropy. Results: Both approaches to defining mutual information lead to the known relationship that mutual information is equal to the pretest uncertainty of the disease state minus the expected value of the posttest uncertainty of the disease state. Mutual information also has the property of being additive when a test provides information about independent health problems. Conclusion: Mutual information is the best single measure of the ability of a diagnostic test to discriminate among the possible disease states.
Ubicomp4D: infrastructure and interaction for international development--the case of urban indian slums

This paper attempts to re-imagine ubiquitous computing for populations in low-income and information-challenged environments. We examine information infrastructures in mid-sized urban slums of Mumbai and Bangalore in three ways--1) highlighting technologies supporting social networks, 2) examining underlying notions of trust and privacy in building information networks, and 3) discussing protocols and practices around shared access. We then discuss our thoughts on designing for low-income, low-literacy, and resource-challenged communities, presenting new ways to think about the design of ubiquitous technologies for international development. We argue for collaborative exchange between the established strengths of the Information and Communication Technologies for Development (ICT4D) and Ubicomp communities to generate new ways of shaping technologies towards poverty alleviation in previously neglected socio-economic contexts--Ubicomp4D.
Jitter Investigation and Performance Evaluation of a Small-Scale Probe Storage Device Prototype

MEMS-based scanning-probe data storage devices are emerging as potential ultra-high-density, low-access-time, and low-power alternatives to conventional data storage. Thermomechanical probe-based storage on thin polymer films is arguably the most advanced scanning-probe data storage scheme. The performance evaluation of a small-scale storage device prototype based on this concept is presented. The emphasis is on understanding the timing jitter in the read-back signals. Experiments are performed that confirm that the primary source of timing-jitter is the nanometer-scale perturbations of the micro-scanner while positioning the recording medium relative to the read/write transducers. Analytical estimates of these micro-scanner perturbations are obtained. An extensive performance evaluation, using the experimentally identified channel and medium-noise spectral characteristics, is conducted to study the impact of the microscanner perturbations on the performance of the storage device.
Synthesizing switching logic for safety and dwell-time requirements

Cyber-physical systems (CPS) can be usefully modeled as hybrid automata combining the physical dynamics within modes with discrete switching behavior between modes. CPS designs must satisfy safety and performance requirements. While the dynamics within each mode is usually defined by the physical plant, the tricky design problem often involves getting the switching logic right. In this paper, we present a new approach to assist designers by synthesizing the switching logic, given a partial system model, using a combination of fixpoint computation, numerical simulation, and machine learning. Our technique begins with an over-approximation of the guards on transitions between modes. In successive iterations, the over-approximations are refined by eliminating points that will cause the system to reach unsafe states, and such refinement is performed using numerical simulation and machine learning. In addition to safety requirements, we synthesize models to satisfy dwell-time constraints, which impose upper and/or lower bounds on the amount of time spent within a mode. We demonstrate using case studies that our technique quickly generates intuitive system models and that dwell-time constraints can help to tune the performance of a design.
Changes in Phosphatidylcholine Headgroup Tilt and Water Order Induced by Monovalent Salts: Molecular Dynamics Simulations

The association between monovalent salts and neutral lipid bilayers is known to influence global bilayer structural properties such as headgroup conformational fluctuations and the dipole potential. The local influence of the ions, however, has been unknown due to limited structural resolution of experimental methods. Molecular dynamics simulations are used here to elucidate local structural rearrangements upon association of a series of monovalent Na+ salts to a palmitoyl-oleoyl-phosphatidylcholine bilayer. We observe association of all ion types in the interfacial region. Larger anions, which are meant to rationalize data regarding a Hofmeister series of anions, bind more deeply within the bilayer than either Cl− or Na+. Although the simulations are able to reproduce experimentally measured quantities, the analysis is focused on local properties currently invisible to experiments, which may be critical to biological systems. As such, for all ion types, including Cl−, we show local ion-induced perturbations to headgroup tilt, the extent and direction of which is sensitive to ion charge and size. Additionally, we report salt-induced ordering of the water well beyond the interfacial region, which may be significant in terms of hydration repulsion between stacked bilayers.
The paraprofessional movement as a paradigm community psychology endeavor.

Community psychology can be seen as a vigorous, action-oriented movement. It is, however, still in the developmental stage characterized by the continued attempts to specify the goals and parameters of the field. The growing paraprofessional movement shares similar origins to community psychology and appears to provide answers to some of the questions raised about the accomplishments of the practitioners of community psychology. Some of the stated goals of community psychology are briefly reviewed and the paraprofessional movement is described in greater detail in an attempt to demonstrate the relationship between the accomplishments and trends of the paraprofessional movement and the goals espoused by community psychologists.
Microsatellite primers for the narrowly endemic shrub Eriogonum giganteum (Polygonaceae).

PREMISE OF THE STUDY Microsatellite primers were designed for Eriogonum giganteum var. formosum, an endemic shrub of San Clemente Island, to investigate population structure, genetic diversity, and demographic history. METHODS AND RESULTS Twelve polymorphic microsatellite loci were isolated from the California Channel Island endemic Eriogonum and were screened for variability. The primers amplified one to eight alleles in the target taxon. Many primers also amplified in conspecific and congeneric (E. arborescens, E. fasciculatum, E. grande, E. latifolium, and E. parvifolium) taxa and in the closely related Chorizanthe valida. The total number of alleles per locus for all taxa screened ranged from three to 24. CONCLUSIONS These primers will be useful for conservation genetic and evolutionary studies within the California Channel Island endemic Eriogonum.
p38 Signaling-mediated Hypoxia-inducible Factor 1α and Vascular Endothelial Growth Factor Induction by Cr(VI) in DU145 Human Prostate Carcinoma Cells

Chromium(VI) (Cr(VI)) is widely used in industry and is a potent inducer of tumors in animals. The present study demonstrates that Cr(VI) induces hypoxia-inducible factor 1 (HIF-1) activity through the specific expression of HIF-1alpha but not HIF-1beta subunit and increases the level of vascular endothelial growth factor (VEGF) expression in DU145 human prostate carcinoma cells. To dissect the signaling pathways involved in Cr(VI)-induced HIF-1 expression, we found that p38 mitogen-activated protein kinase signaling was required for HIF-1alpha expression induced by Cr(VI). Neither phosphatidylinositol 3-kinase nor extracellular signal-regulated kinase activity was required for Cr(VI)-induced HIF-1 expression. Cr(VI) induced expression of HIF-1 and VEGF through the production of reactive oxygen species in DU145 cells. The major species of reactive oxygen species responsible for the induction of HIF-1 and VEGF expression is H(2)O(2). These results suggest that the expression of HIF-1 and VEGF induced by Cr(VI) may be an important signaling pathway in the Cr(VI)-induced carcinogenesis.
Deterministic Symmetric Positive Semidefinite Matrix Completion

We consider the problem of recovering a symmetric, positive semidefinite (SPSD) matrix from a subset of its entries, possibly corrupted by noise. In contrast to previous matrix recovery work, we drop the assumption of a random sampling of entries in favor of a deterministic sampling of principal submatrices of the matrix. We develop a set of sufficient conditions for the recovery of a SPSD matrix from a set of its principal submatrices, present necessity results based on this set of conditions and develop an algorithm that can exactly recover a matrix when these conditions are met. The proposed algorithm is naturally generalized to the problem of noisy matrix recovery, and we provide a worst-case bound on reconstruction error for this scenario. Finally, we demonstrate the algorithm's utility on noiseless and noisy simulated datasets.
Autonomic computing and reliability improvement

The rapidly increasing complexity of systems is driving the movement towards autonomic systems that are capable of managing themselves without the need for human intervention. Without autonomic technologies, many conventional systems suffer reliability degradation due to the accumulation of errors. The autonomic management techniques break the traditional reliability degradation trend. This paper comprehensively describes the roles and functions of various autonomic components, and systematically reviews past and current technologies that have been developed to address the specific areas of the autonomic computing environment. A new mechanism of model-driven autonomic management is further presented, which is more intelligent and efficient.
The coastal-disjunct mesic flora in the inland Pacific Northwest of USA and Canada: refugia, dispersal and disequilibrium.

Aim Understanding the history of the mesic-adapted plant species of eastern British Columbia and northern Idaho, disjunct from their main coastal distribution, may suggest how biotas reorganize in the face of climate change and dispersal barriers. For different species, current evidence supports establishment of the disjunction via an inland glacial refugium, via recent dispersal from the coast, or via a combination of both. In this study, the modern distributions of the coastal-disjunct vascular plants are analysed with respect to modern climate to examine how refugia and/or dispersal limitation control regional patterns in species richness. Location North-west North America. Methods The distributions of nine tree and 58 understorey species with a coastaldisjunct pattern were compiled on a 50-km grid. The relationship between species richness and an estimate of available moisture was calculated separately for formerly glaciated and unglaciated portions of the coastal and inland regions. Growth habit and dispersal mode were assessed as possible explanatory variables for species distributions. Results Species richness shows a strong relationship to climate in coastalunglaciated areas but no relationship to climate in inland-glaciated areas. In inland-glaciated areas, richness is c. 70% lower than that expected from climate. Species with animal-dispersed seeds occupy a larger portion of coastal and inland regions than species with less dispersal potential. Main conclusions Modern patterns of diversity are consistent with both refugia and dispersal processes in establishing the coastal-disjunct pattern. The inland glacial refugium is marked by locally high diversity and several co-distributed endemics. In the inland-glaciated area, dispersal limitation has constrained diversity despite the nearby refugia. Onset of mesic climate within only the last 3000 years and the low dispersal capacity of many species in the refugium may explain this pattern. This study suggests that vascular plant species will face significant challenges responding to climate change on fragmented landscapes.
Induction of apoptosis in fetal pulmonary arterial smooth muscle cells by a combined superoxide dismutase/catalase mimetic.

Reactive oxygen species (ROS) such as superoxide and hydrogen peroxide are known to play an important role in the proliferation and viability of vascular smooth muscle cells. In this study, we dete...
Multiple-Target Tracking by Spatiotemporal Monte Carlo Markov Chain Data Association

We propose a framework for tracking multiple targets, where the input is a set of candidate regions in each frame, as obtained from a state-of-the-art background segmentation module, and the goal is to recover trajectories of targets over time. Due to occlusions by targets and static objects, as also by noisy segmentation and false alarms, one foreground region may not correspond to one target faithfully. Therefore, the one-to-one assumption used in most data association algorithms is not always satisfied. Our method overcomes the one-to-one assumption by formulating the visual tracking problem in terms of finding the best spatial and temporal association of observations, which maximizes the consistency of both motion and appearance of trajectories. To avoid enumerating all possible solutions, we take a data-driven Markov Chain Monte Carlo (DD-MCMC) approach to sample the solution space efficiently. The sampling is driven by an informed proposal scheme controlled by a joint probability model combining motion and appearance. Comparative experiments with quantitative evaluations are provided.
Edward Epstein's Stochastic–Dynamic Approach to Ensemble Weather Prediction

In the late 1960s, well before the availability of computer power to produce ensemble weather forecasts, Edward Epstein (1931–2008) developed a stochastic–dynamic prediction (SDP) method for calculating the temporal evolution of mean value, variance, and covariance of the model variables: the statistical moments of a time-varying probability density function that define an ensemble forecast. This statistical–dynamical approach to ensemble forecasting is an alternative to the Monte Carlo formulation that is currently used in operations. The stages of Epstein's career that led to his development of this methodology are presented with the benefit of his oral history and supporting documentation that describes the retreat of strict deterministic weather forecasting. The important follow-on research by two of Epstein's proteges, Rex Fleming and Eric Pitcher, is also presented. A low-order nonlinear dynamical system is used to discuss the rudiments of SDP and Monte Carlo and to compare these approximate methods...
Fatty Acid Regulation of Enteric Infectious Disease

Bacterial infections of the digestive tract afflict billions of people each year. These include infections such as travelers’ diarrhea, cholera, and salmonella. The gram negative bacteria that cause these infections all function by using a genetic cascade to control the expression of virulence factors, and thus control infection. In the bacterium Vibrio cholerae, this process is controlled by a member of the AraC/Xyls transcription factor family, ToxT. Results from our lab, including the crystal structure of ToxT, have shown that ToxT is capable of binding a fatty acid, causing a conformational change and preventing DNA binding. This conformational change suppresses the virulence cascade in V. cholerae. Because many other AraC/XylS family members also control virulence cascades, we have begun an examination of the mechanism of action of these related proteins in hopes of discovering a common effector. We are using a combination of computational and biochemical methods to determine if fatty acids could function to repress other AraC/XylS family members and thus repress the virulence cascade in a variety of infectious bacteria.
Distributed construction of a planar spanner and routing for ad hoc wireless networks

Several localized routing protocols (see Bose, P. and Morin, P., Proc. 10th Annual Int. Symp. on Algorithms and Computation ISAAC, 1999) guarantee the delivery of packets when the underlying network topology is the Delaunay triangulation of all wireless nodes. However, it is expensive to construct the Delaunay triangulation in a distributed manner. Given a set of wireless nodes, we more accurately model the network as a unit-disk graph, UDG, in which a link between two nodes exists only if the distance between them is at most the maximum transmission range. Given a graph H, a spanning subgraph G of H is a t-spanner if the length of the shortest path connecting any two points in G is no more than t times the length of the shortest path connecting the two points in H. We present a novel localized networking protocol that constructs a planar 2.5-spanner of UDG, called the localized Delaunay triangulation, as network topology. It contains all edges that are in both the UDG and the Delaunay triangulation of all wireless nodes. Our experiments show that the delivery rates of existing localized routing protocols are increased when localized Delaunay triangulation is used instead of several previously proposed topologies. The total communication cost of our networking protocol is O(n log n) bits. Moreover, the computation cost of each node u is O(d/sub u/ log d/sub u/), where d/sub u/ is the number of 1-hop neighbors of u in UDG.
Effects of intermittent stretching exercises at work on musculoskeletal pain associated with the use of a personal computer and the influence of media on outcomes.

Objective: The objective of this study was to evaluate the effects of regular stretching exercises on pain associated with working at a computer workstation, and to ascertain whether the type of media used for exercise instruction had an effect on outcomes. Participants: Sixty-eight volunteers were divided into three equivalent groups. All of the subjects worked at computers for prolonged periods of time and reported that their pain had been a source of distress for at least three weeks prior to the intake evaluation. Methods: A pretest-posttest-control group design with cluster randomization was used to evaluate the effect of a stretching program on pain. Thirty-six different stretches were performed by the subjects for 15-17 work days. Two intervention groups were directed to stretch once every six minutes. One group (n = 22) was reminded to stretch via a computer program, the second group (n = 23) by using a hard copy version of the stretches with pictures and written instructions, and a third group received no intervention. Results: ANOVA analysis found a significant reduction in pain of 72% ( p< 0.001) for the computer-generated stretching program, and of 64% ( p< 0.001) using the hardcopy version of the intervention. The control group had an increase in pain of 1%. Conclusions: Both software and hard copy stretching interventions contributed to a decrease in pain without making any changes to workstation ergonomics and there was no significant statistical difference in the outcomes of either intervention. The subjective evaluation of pain using both visual analog scales and a newly created "pain spot" assessment technique yielded similar results.
Substance P and Fibromyalgia

(1998). Substance P and Fibromyalgia. Journal of Musculoskeletal Pain: Vol. 6, No. 3, pp. 29-35.
Effects of Habitat Patchiness on Population Dynamics: A Modelling Approach

I used the STELLAIIR simulation language to model small mammal population dynamics in a landscape consisting of an optimal and a marginal habitat patch. A cyclic optimal-patch population was simulated, and dispersal between optimal and marginal patches was modelled in two ways: a Social Fence model, in which immigration into marginal habitat was sensitive to population density in the marginal patch; and a Resource Fence model, in which immigration rate was determined by resource availability in both habitat types. Quality of the marginal patch was manipulated and responses of the population in the optimal patch observed. For the Social Fence model, increasing the area or decreasing demographic performance (i.e. decreasing natality and increasing mortality rates) in the marginal patch stabilized dynamics in the optimal patch. This model was insensitive to changes in resource availability in marginal habitat. For the Resource Fence model, large size and intermediate values of resource availability in the marginal habitat were most stabilizing for the optimal patch population. This model was relatively insensitive to changes in marginal patch demography. Multiannual cycles disappeared when strict female territoriality was simulated, but they persisted under a more flexible, and realistic, semiterritorial system. The results suggest that population responses to patchy landscapes will depend strongly on the factors affecting dispersal rates among patch types.
Two-body form factors at high Q 2

The charge form factor of a scalar deuteron at high momentum transfer is examined in a model employing scalar nucleons and mesons. With an eye towards establishing consistency criteria for more realistic calculations, several aspects of the model are examined in detail: the role of nucleon and meson singularities in the one-loop impulse diagram, the role of positive- and negative-energy nucleons, and the relationship to time-ordered perturbation theory. It is found that at large Q/sup 2/ (1) the form factor is dominated by a term in which the spectator nucleon is on the mass shell, and (2) the meson singularity structure of the d-n-p vertex function is unimportant in determining the overall high-Q/sup 2/ behavior of the form factor.
Management of Apparently Inappropriate Therapeutic Drug Monitoring Data

The explosive advance of technology has made drug assays widely available for therapeutic monitoring, but the understanding of such data has not progressed as rapidly. Therefore, the pathologist should provide consultation to the clinician when apparently inappropriate drug monitoring data are obtained. This task can be approached in a systematic fashion by answering the following four questions of a simple logic tree: 1) Is the blood drug concentration within the therapeutic range? 2) Was the sample inappropriate? 3) Are special circumstances absent in the patient? 4) Are the special circumstances reversible?
Evidence for the kinetic partitioning of polymerase activity on G-quadruplex DNA

We have investigated the action of the human DNA polymerase e (hpol e) and η (hpol η) catalytic cores on G-quadruplex (G4) DNA substrates derived from the promoter of the c-MYC proto-oncogene. The translesion enzyme hpol η exhibits a 6.2-fold preference for binding to G4 DNA over non-G4 DNA, while hpol e binds both G4 and non-G4 substrates with nearly equal affinity. Kinetic analysis of single-nucleotide insertion by hpol η reveals that it is able to maintain >25% activity on G4 substrates compared to non-G4 DNA substrates, even when the primer template junction is positioned directly adjacent to G22 (the first tetrad-associated guanine in the c-MYC G4 motif). Surprisingly, hpol η fidelity increases ∼15-fold when copying G22. By way of comparison, hpol e retains ∼4% activity and has a 33-fold decrease in fidelity when copying G22. The fidelity of hpol η is ∼100-fold greater than that of hpol e when comparing the misinsertion frequencies of the two enzymes opposite a tetrad-associated guanine. The kinetic ...
Drop-off detection with the long cane: effect of cane shaft weight and rigidity on performance

Most travellers who are blind rely on a long cane to detect drop-offs on their walking paths. We examined how different cane shaft materials affect drop-off detection performance through providing different vibrotactile and proprioceptive feedbacks to the cane user. Results of the study showed a significant interaction between cane shaft weight and how the cane is used. A heavier cane was advantageous for detecting drop-offs when the individual used the 'constant contact technique' - cane tip stays in contact with the walking surface at all times - but not when he used the 'two-point touch technique' - cane tip is rhythmically tapped on the surface. In addition, a more flexible cane was advantageous for detecting drop-offs when the two-point touch technique was used but not when the constant contact technique was used. It is recommended that, when blind individuals select a cane shaft material, they consider which long cane technique they use more often. Practitioner Summary: Long cane shaft material affects how well a blind individual can detect drop-offs. A heavier shaft was advantageous when using the constant contact technique (cane tip stays in continuous contact with the surface), while a more flexible shaft was better when using the two-point touch technique (cane tip rhythmically taps the surface).
Stress hyperglycemia and surgical site infection in stable nondiabetic adults with orthopedic injuries.

BACKGROUNDHyperglycemia in nondiabetic patients outside the intensive care unit is not well defined. We evaluated the relationship of hyperglycemia and surgical site infection (SSI) in stable nondiabetic patients with orthopedic injuries.METHODSWe conducted a prospective observational cohort study a