cssi/SciSciGPT-SciSciNet huggingface dataset:
Finite Element Analysis of the Crimping Process of the Piston-slipper Component in Hydraulic Pumps

Hydraulic pumps and motors are widely used in mobile equipment for construction, mining and agriculture. The piston-slipper component is one of the critical parts of a hydraulic pump. A crimping process is used for connecting the piston to the slipper component. Like most of the manufacturing processes that involve large deformations, high stresses are created in the slipper and piston during the crimping process. This paper presents a finite element method for the analysis of the stresses, strains, and forces associated with the crimping process. This method can be used in the optimization of the piston, slipper and die designs. The commercial finite element package ANSYS was used to simulate the crimping process. The simulation procedure is used to obtain a better understanding of the effect of the die geometry on the crimping process.
Protein phosphatases modulate the apparent agonist affinity of the light-regulated ion channel in retinal rods

Ion channels directly activated by cGMP mediate the light response in retinal rods. Several components of the enzyme cascade controlling cGMP concentration are regulated, but there are no accepted mechanisms for modulation of the response of the channel to cGMP. Here we report evidence that in excised patches an endogenous protein phosphatase converts the channel from a state with low cGMP sensitivity to a state with almost 3 orders of magnitude higher sensitivity in the predicted physiological range of cGMP concentration. The action of this endogenous phosphatase was blocked by specific serine/threonine phosphatase inhibitors (microcystin-LR, okadaic acid, and calyculin A). An increase in apparent agonist affinity also was produced by addition of purified protein phosphatase 1. In contrast, protein phosphatase 2A decreased apparent agonist affinity, suggesting that two phosphorylation sites may regulate the agonist sensitivity of the channel in a reciprocal manner. This regulation may be involved in fine-tuning the light response or in light or dark adaptation.
Current status of class III antiarrhythmic drug therapy

Studies in animal models, as well as clinical experience with amiodarone and sotalol, suggest that action potential prolongation may be a useful antiarrhythmic mode of action. A number of agents that produce this class III effect are currently under development. The single greatest liability for further development of this group of drugs is the occasional, and apparently unpredictable, development of exaggerated QT prolongation and polymorphic ventricular tachycardia (torsades de pointes). Available data suggest that QT interval prolongation is not a good indicator of whether or not a class III antiarrhythmic will suppress a target arrhythmia; however, exaggerated QT prolongation is a predictor of torsades de pointes. Further studies to delineate the mechanism underlying the development of torsades de pointes might lead to safer and more effective antiarrhythmic drugs.
Fourier-space paths applied to the calculation of diffusion for the Chirikov-Taylor model

A compact path-diagram method has been introduced for the calculation of velocity moments of a probability function. This method is complementary to the approach developed earlier by Rechester and White. It is applied to the Chirikov-Taylor model. Analytic expressions for velocity-space diffusion have been derived and compared with numerical computations. A numerical method for path summations has been developed which is more efficient than directly advancing the model equations, and is applicable for small field-amplitude values, where the direct stepping method is impractical.
Stress-associated poor health among adult immigrants with a language barrier in the United States.

The healthy migrant hypothesis supported by the ‘Hispanic paradox’ suggests that immigrants are healthier than non-immigrants. To test the generalizability of this hypothesis, we studied the stress-associated health status of adult immigrants with a language barrier in the USA. Three stress-related conditions (Unhappiness, Depression, and Anxiety) and self-reported health status were ascertained from participants of the Community Tracking Study Health Survey conducted in 2003. The associations between these conditions as well as the immigrants’ length of time living in the USA and health were assessed. Our results demonstrated that the three stress-related conditions were significantly associated with a dramatically elevated poor health status (Unhappiness: OR = 5.22, 95% CI: 4.43–6.14; Depression: OR = 3.03, 95% CI: 2.31–3.98; Anxiety: OR = 5.12, 95% CI: 3.53–7.41). Compared to US citizens without a language barrier, immigrants with a language barrier were more likely to report poor health (OR = 2.15, 95% CI: 1.66–2.78). After adjustment for stressors, the likelihood of reporting poor health among immigrants with a language barrier decreased significantly (OR = 1.75, 95% CI: 1.05–2.91). In addition, these immigrants were more likely to report poor health within the first 10 years of their living in the USA (≤5 years: OR = 2.79, 95% CI: 1.94–4.02; 6–10 years: OR = 2.68, 95% CI: 1.86–3.86). In summary, immigrants who have a language barrier were generally more stressed, especially at the beginning of their lives as immigrants. The combined effect of stress and a language barrier led to poorer health in these immigrants. Thus, the healthy migrant hypothesis may not be generalizable to this population.
A major role for the EP4 receptor in regulation of renin.

Prostaglandins have been implicated as paracrine regulators of renin secretion, but the specific pathways and receptor(s) carrying out these functions have not been fully elucidated. To examine the...
Structures and Stabilization Mechanisms in Chemically Stabilized Ceramics

Abstract Structural complexities and disorder in chemically stabilized cristobalites (CSC), which are room temperature silica-based ceramics, prepared by a wet chemical route, are described. CSC displays many of the structural characteristics of the high temperature cristobalite, elucidated by HREM and X-ray diffraction. In-situ electron diffraction and NMR results suggest that the disorder is structural and is static.
First-principles energetics of hydrogen traps in α-Fe: Point defects

Abstract We performed a series of density functional theory (DFT) calculations to quantify the binding energy of hydrogen to a number of point defects in body-centered cubic Fe, e.g. vacancies, interstitial carbon and substitutional solutes. We found the following: (i) Vacancies are the strongest H trap, with a binding energy of 0.57 eV. (ii) The binding energy of H to C is 0.09 eV. (iii) Most substitutional solutes (except Si, Cr, Mn, Co, and Mo) trap H with positive binding energies up to 0.25 eV. The maximum H binding energy for Si, Cr, Mn, Co and Mo is essentially zero, meaning they do not interact with H. (iv) The H–substitutional solute binding energies are roughly correlated with the solute atom’s electronegativity and size. (v) The presence of a solute atom near a vacancy does not affect hydrogen binding to the vacancy provided the solute atom is not significantly larger than Fe.
The enhanced sensitivity of mammalian cells to killing by X rays after prolonged exposure to several nitroimidazoles

Electron affinic compounds, such as misonidazole, preferentially sensitize hypoxic cells to killing by X rays, and are also preferentially cytotoxic to cells deficient in oxygen. Prolonged exposure of cells to misonidazole prior to irradiation results in an increased radiosensitization. This is expressed as the Extra Enhancement Ratio (EER), defined as the ratio of the doses delivered immediately after the addition of the sensitizer or after prolonged incubation, that produce a given biological effect. Chinese hamster V79 cells have been used to investigate this prolonged incubation effect for a variety of 2-nitroimidazoles including misonidazole, desmethylmisonidazole and SR-2508 and as well as two ortho-substituted-4-nitroimidazoles with a bromine or sulfonamide group substituted in the 5-position. A considerable variation was observed in the magnitude of the Extra Enhancement Ratio (EER) produced by pre-incubation with different compounds at concentrations that produce the same sensitizing effect. There is a good correlation between the EER and the measured rate at which the various sensitizers deplete cells of non-protein sulfhydryl compounds. There is also a good correlation between the EER and the fraction of cells killed by the pre-incubation period in the drug.
Establishing on-orbit calibration links among operational satellite radiometers for the implementation of GEOSS

ABSTRACT Numerical weather prediction and climate change detection studies critically depe nd on accurate, reliable, and consistent satellite radiance data from multiple sensors onboard a constellation of satellites. The calibration consistency across international satellites is further challenged in the implementation of GEOSS (Global Earth Observation System of Systems). As a result, establishing on -orbit calibration links among op erational satellite radiometers has become critical. This paper provides an overview of the current status and challenges in the on-orbit calibration traceability among operational satellite radiometers. It then proposes to develop an on-orbit calibration reference network to establish the calibration links. The Simultaneous Nadir Overpass method for intersatellite calibration is a key methodology for the network. Other methodologies including vicarious calibration, moon calibration, and airborne campaigns will also be used to support the network. Example applications of the network for operational satellite radiometers are demonstrated. By establishing an on-orbit calibration ne twork that makes the calibration of simi lar radiometers traceable to each other, a quasi on-orbit calibration standard can be established in the long-term. The system will help us diagnose radiance biases for data assimilation and time series analysis. It will also bring together a world of radiometers to facilitate the implementation of GEOSS. Keywords: On-orbit calibration reference network, radiometer, inter-satellite calibration.
A Simple Model of the Treloar-Kearsley Instability

The Treloar—Kearsley instability is studied in the framework of membrane theory. The phenomenon considered is the bifurcation of an equibiaxial stretch of a thin square elastic sheet, in equilibriu...
EXPLORING SPATIAL REASONING ABILITY AND DESIGN COGNITION IN UNDERGRADUATE ENGINEERING STUDENTS

This paper presents preliminary results from the first phase of a longitudinal study of design cognition and the effects of design education on design practice. The study aims to monitor the development of engineering design thinking through a three-year protocol study of control and experimental groups of engineering students. Using innovations in cognitive science that include ontologically-based coding of protocols and new methods of protocol analysis, the study is intended to characterize students’ cognitive development, identify differences over time, and relate those differences to students’ educational experiences. The first phase of this study focuses on assessing students’ spatial reasoning ability. Spatial reasoning is the ability to process and form ideas through spatial relationships among objects. It has been found to correlate strongly with the design ability associated with one’s ability to generate, conceptualize, and communicate solutions to problems. Sophomore students entering two different majors took four spatial reasoning tests (Paper Folding, Vandenberg, Mental Rotation, and Spatial Imagery Ability) that addressed their ability to visualize objects and mentally manipulate them over an ordered sequence of spatial transformations. The results of these tests are presented in this paper. Tests were conducted to determine statistical significance in order to evaluate whether a student’s spatial reasoning ability correlates with their choice of engineering major. The students’ test performances are also compared with existing data from other fields (e.g., architecture, visual arts, science, and humanities).Copyright © 2010 by ASME
Users' evaluation of digital libraries (DLs): Their uses, their criteria, and their assessment

Millions of dollars have been invested into the development of digital libraries. There are many unanswered questions regarding their evaluation, in particular, from users' perspectives. This study intends to investigate users' use, their criteria and their evaluation of the two selected digital libraries. Nineteen subjects were recruited to participate in the study. They were instructed to keep a diary for their use of the two digital libraries, rate the importance of digital library evaluation criteria, and evaluate the two digital libraries by applying their perceived important criteria. The results show patterns of users' use of digital libraries, their perceived important evaluation criteria, and the positive and negative aspects of digital libraries. Finally, the relationships between perceived importance of digital library evaluation criteria and actual evaluation of digital libraries and the relationships between use of digital libraries and evaluation of digital libraries as well as users' preference, experience and knowledge structure on digital library evaluation are further discussed.
Individual difference influences on self-focused and other-focused counterproductive student behaviors

This paper extends previous research on counterproductive student behaviors by presenting an individual difference model of counterproductive student behaviors (CSBs) that includes four sets of antecedent variables: internal control variables; propensity variables; achievement striving; and severity perceptions of CSBs. Data from 276 undergraduate students shows that CSBs exhibit a two-factor solution (self-focused and other-focused CSBs), and that each of the four sets of antecedent variables explain unique variance in either self-focused CSBs or other-focused CSBs; with the influence of achievement striving being restricted to behaviors that harm the academic performance of students. The results are discussed in terms of their relationship with previous research on counterproductive behaviors and their implications for understanding of the broad domain of college student performance.
A one-step electrochemical synthesis of polyaniline-polypyrrole composite coatings on carbon fibers

Abstract Polyaniline–polypyrrole composite coatings were formed on carbon fibers by potentiostatic electrochemical polymerization. Electropolymerization was done by varying the applied potential and molar feed ratio of monomers. The dual nature of the composite coatings was deduced from the current–time ( I – t ) curves traced during polymerization. I – t curves were also used to predict the mechanism of the formation of composite coatings. UV–vis absorption spectroscopy was used to study the electronic structure of the composite coatings.
In-situ measurement of radiation-induced conductivity of thin film ceramics

A test chamber has been constructed to measure the in-situ DC electrical conductivity of ceramic thin films during ion irradiation. The films can be irradiated by three separate ion beams simultaneously with sufficient energy to pass through the films. The radiation induced conductivity of a thin (∼1.5 μm) Al 2 O 3 film on tantalum was measured at ionization rates between 10 3 and 10 6 Gy/s. Radiation-induced conductivity comparable to that previously reported in bulk alumina was observed. Prolonged irradiation at elevated temperature and under an applied electric field resulted in a permanent increase in the conductance of the film. The test chamber is described and some preliminary results are given
Affinity purification and properties of porcine brain aldose reductase

Abstract Aldose reductase (alditol:NADP+ 1-oxidoreductase, EC 1.1.1.21) has been purified 1500-fold from porcine brain in a four-step procedure employing Blue-Sepharose 6B affinity chromatography. The purified enzyme was shown to be apparently homogeneous by polyacrylamide gel electrophoresis. The enzyme is a single chain polypeptide of molecular weight 40 000, pH optimum 5.0, K xylose app 4mM; K NADPH app 3 μM. The relative substrate activities, activation with sulfate ion, and limited oxidative and NADH-related reductive activities confirm the classification of this enzyme as aldolase reductase. The activity of the reductase with p- nitrobenzaldehyde and 3-indolacetaldehyde and the similarity of its physical properties with the ‘low K m ’ aldehyde reductase of porcine brain previously reported indicates that these enzymes may be identical.
Mathematical skills in Williams syndrome: Insight into the importance of underlying representations

Williams syndrome (WS) is a developmental disorder characterized by relatively spared verbal skills and severe visuospatial deficits. Serious impairments in mathematics have also been reported. This article reviews the evidence on mathematical ability in WS, focusing on the integrity and developmental path of two fundamental representations, namely those that support judgments of "how much" (i.e., magnitude) and "how many" (i.e., number of objects). Studies on magnitude or "number line" representation in WS suggest that this core aspect of mathematical ability, is atypical in WS throughout development, causing differences on some but not all aspects of math. Studies on the representation of small numbers of objects in WS are also reviewed, given the proposed links between this type of representation and early number skills such as counting. In WS, representation appears to be relatively typical in infancy but limitations become evident by maturity, suggesting a truncated developmental trajectory. The math deficits in WS are consistent with neurological data indicating decreased gray matter and hypoactivation in parietal areas in WS, as these areas are implicated in mathematical processing as well as visuospatial abilities and visual attention. In spite of their deficits in core mathematical representations, people with WS can learn many mathematical skills and show some strengths, such as reading numbers. Thus individuals with WS may be able to take advantage of their relatively strong verbal skills when learning some mathematical tasks. The uneven mathematical abilities found in persons with WS provide insight into not only appropriate remediation for this developmental disorder but also into the precursors of mathematical ability, their neural substrates, and their developmental importance.
The Scaling of Sociometric Nominations.

A 29-item sociometric nominations instrument (Guess Who) was administered to 13,045 children in 603 elementary classes. An image analysis of the frequencies of nomination on the items yielded four factors: Disruptive, Bright, Dull, and Quiet-Well Behaved. Four scaling methods were compared with regard to class-size bias: raw frequencies, division by class N, binary truncation, and standardization within classes. Binary item-frequency truncation yielded scores which were demonstrated to have superior external validity using diagnostic groups, self-reports, and teacher ratings as criteria. Internal consistency reliabilities for the four factor scales ranged from .61 to .77, while split class reliabilities ranged from .56 to .74.
Identification of Ingested Prey Fish Based on Scale Characteristics

Abstract Scale analysis of ingested prey fish was investigated as a possible method for determining the feeding ecology of piscivorous brown trout (Salmo trutta) in Bottom Creek, Virginia. Comparisons of ingested prey scales and reference scales of potential prey were made using phase-contrast microscopy and specific scale morphometry criteria. With this method, 94% of fish remains in brown trout digestive tracts were identified to species. Determinations with scales proved consistently accurate where identifications based on external features were possible.
Light storage in an optically thick atomic ensemble under conditions of electromagnetically induced transparency and four-wave mixing

We study the modification of a traditional electromagnetically induced transparency (EIT) stored-light technique that includes both EIT and four-wave mixing (FWM) in an ensemble of hot Rb atoms. The standard treatment of light storage involves the coherent and reversible mapping of one photonic mode onto a collective spin coherence. It has been shown that unwanted, competing processes such as four-wave mixing are enhanced by EIT and can significantly modify the signal optical pulse propagation. We present theoretical and experimental evidence to indicate that, while a Stokes field is indeed detected upon retrieval of the signal field, any information originally encoded in a seeded Stokes field is not independently preserved during the storage process. We present a simple model that describes the propagation dynamics of the fields and the impact of FWM on the spin wave.
Deep crustal geothermal measurements, hole 504B, Costa Rica Rift

We report an extensive suite of geothermal measurements in the deepest borehole yet drilled into the oceanic crust, hole 504B of the Deep Sea Drilling Project. Located in 6.2-m.y.-old crust of the Costa Rica Rift, hole 504B was cored during legs 69 and 70 in late 1979 and leg 83 in late 1981, to a total depth of 1350 m beneath the seafloor, through 274.5 m of sediment and 1075.5 m of basalt. During the three drilling legs, downhole temperatures were logged 11 times, and the thermal conductivities of 239 sediment and basalt samples were measured. The results indicate a dominantly conductive mode of heat transfer through the complete section, at 190±10 mW/m2. This is consistent with the predicted plate heat transfer and the hypothesis that the thick sediment cover acts as a seal against hydrothermal circulation of seawater to basement. For over 2 years after this sediment seal was penetrated, borehole temperatures were nearly isothermal to about 350–370 m, indicating that ocean bottom water was flowing down the hole into the upper ∼100 m of basement. This downhole flow was driven by the underpressure of the basement pore fluids, which is of indefinite, but possibly hydrothermal, origin (Anderson and Zoback, 1982). The flow rate decreased from 6000–7000 1/h in late 1979 to about 1500 1/h 2 years later; altogether over 50×106 kg of seawater has been drawn into the basement. We estimate a permeability of ≳6×10−14 m2 for the reservoir in the upper ∼100 m of basement. This zone seems to correspond to a layer of high apparent porosity (Becker et al., 1982), which has been tentatively identified as a thin layer 2A (Anderson et al., 1982a).
Interaction of 24.0- and 27.2-MeV neutrons with deuterons

The angular distributions of 24.0- and 27.2-MeV neutrons scattered elastically by deuterons through angles between 90 and 166 deg (c.m.) were measured. Proton-emission-energy spectra were studied at 11 and 22 deg (lab) and angular distributions were measured between 11 and 46 deg (lab). The spectra and angular distributions were normalized to the n-p differential cross section at 158 deg (c.m.). The minimum cross sections of neutrons elastically scattered by deuterons were found to be less than the minimum cross sections of elastically scattered protons. (auth)
Kinetic properties of cholinergic desensitization in Aplysia neurons

The kinetic properties of desensitization onset of excitatory cholinergic responses were studied in isolated, voltage-clamped Aplysia neurons. Desensitization of the acetylcholine (ACh)-induced current in response to microperfused acetylcholine occurred in two phases, and was best modelled as the sum of two exponential components plus a constant. Both exponential components were accelerated by increasing ACh dose. At the higher ACh doses the current decline was dominated by the fast exponential component, and the ratio of the plateau-peak current was reduced. Over the range of membrane potentials -50 to -110 mV, no change in the kinetics of desensitization onset was observed. The mean time constants of both exponential components were doubled by cooling from 20 degrees C to 5 degrees C. These results demonstrate that, as at the vertebrate neuromuscular junction, the onset of desensitization of this ACh response involves at least two processes which are dose- and temperaturesensitive. The lack of voltage dependence contrasts with results from vertebrate preparations, and indicates a fundamental difference between the properties of the excitatory ACh response in Aplysia neurons and the vertebrate neuromuscular junction.
Meal-induced increase in plasma gastrin immunoreactivity in the rhesus monkey (Macaca mulatta).

The hormonal response to food intake in rodents, dogs, and humans involves gastrin and cholecystokinin, structurally related peptides present in plasma, gut, and brain. In order to determine the time course of plasma gastrin response in a nonhuman primate, six overnight-fasted adult male rhesus monkeys were offered a meal of bananas (11g) and peanut butter (1 Tbsp) or a fresh water bottle in a crossover design. All animals completely consumed the meal within 10 min. Compared to non-fed control levels, plasma gastrin was significantly elevated (52 ± 11 pM vs. 32 ± 9 pM, means ± S. E. M.) from 10 to 45 min post-ingestion, but returned to near basal fasted level by 120 min. Levels of gastrin in tissue samples (n = 2) were highest in the antrum of the stomach, with decreasing amounts measured in the upper and lower duodenum, respectively. The results demonstrate that the plasma concentration and response to a meal of rhesus monkey gastrin are similar to those of other mammalian species. However, the high concentrations of gastrin found in duodenum are thus far unique to Macaca mulatta and humans.
The apparent size of the path traversed by a rotating target during saccadic and smooth pursuit: New data on the shrinking circle illusion

Twelve subjects attempted to visually track a continuously or discretely moving target as it rotated through a path 20° in diameter at velocities ranging from .18 to 5.2 cps. Tracking error, resulting from the eye tracking a path inside that of the target, was an increasing function of velocity from .18 to 1.13 cps. Higher velocity targets could not be tracked consistently. Apparent path diameter and the tracking diameter of the eye were both a decreasing function of velocity (through 1.13 cps) in the condition requiring smooth pursuit of a continuously moving target. Tracking diameter was also a decreasing function of velocity for the condition requiring saccadic pursuit of a discretely moving target, but this was not associated with a corresponding decrease in apparent size. These results suggest that the retinal position error generated by undertracking the target is processed during saccadic, but not during smooth, pursuit.
The Effectiveness of U.S. Public Health Surveillance Systems for Situational Awareness during the 2009 H1N1 Pandemic: A Retrospective Analysis

Background The 2009 H1N1 outbreak provides an opportunity to learn about the strengths and weaknesses of current U.S. public health surveillance systems and to identify implications for measuring public health emergency preparedness. Methodology/Principal Findings We adopted a “triangulation” approach in which multiple contemporary data sources, each with different expected biases, are compared to identify time patterns that are likely to reflect biases versus those that are more likely to be indicative of actual infection rates. This approach is grounded in the understanding that surveillance data are the result of a series of decisions made by patients, health care providers, and public health professionals about seeking and providing health care and about reporting cases to health authorities. Although limited by the lack of a gold standard, this analysis suggests that children and young adults are over-represented in many pH1N1 surveillance systems, especially in the spring wave. In addition, the nearly two-month delay between the Northeast and the South in the Fall peak in some surveillance data seems to at least partially reflect regional differences in concerns about pH1N1rather than real differences in pH1N1 infection rates. Conclusions/Significance Although the extent of the biases suggested by this analysis cannot be known precisely, the analysis identifies underlying problems with surveillance systems – in particular their dependence on patient and provider behavior, which is influenced by a changing information environment – that could limit situational awareness in future public health emergencies. To improve situational awareness in future health emergencies, population-based surveillance systems such as telephone surveys of representative population samples and seroprevalence surveys in well-defined population cohorts are needed.
Benefits of hindsight: Design problems in evaluating innovation in medical education

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Preferred and actual participation roles during health care decision making in persons with cancer: a systematic review

The preferred and actual participation roles during decision making have been studied over the past two decades; however, there is a lack of evidence on the degree of match between patients’ preferred and actual participation roles during decision making. A systematic review was carried out to identify published studies that examined preferred and actual participation roles and the match between preferred and actual roles in decision making among patients with cancer. PubMed (1966 to January 2009), PsycINFO (1967 to January 2009), and CINAHL (1982 to January 2009) databases were searched to access relevant medical, psychological, and nursing literature. Twenty-two studies involving patients with breast, prostate, colorectal, lung, gynecological, and other cancers showed discrepancies between preferred and actual roles in decision making. These groups of patients wanted a more shared or an active role versus a less passive role. Across all cancer types, patients wanted more participation than what actually occurred. Research to date documents a pervasive mismatch between patients’ preferred and actual roles during decision making. Yet, there is lack of innovative interventions that can potentially increase matching of patients’ preferred and actual role during decision making. Role preferences are dynamic and vary greatly during decision making, requiring regular clinical assessment to meet patients’ expectations and improve satisfaction with treatment decisions.
Optimal sensor scheduling for resource-constrained localization of mobile robot formations

This paper addresses the problem of resource allocation in formations of mobile robots localizing as a group. Each robot receives measurements from various sensors that provide relative (robot-to-robot) and absolute positioning information. Constraints on the sensors' bandwidth, as well as communication and processing requirements, limit the number of measurements that are available or can be processed at each time step. The localization uncertainty of the group, determined by the covariance matrix of the equivalent continuous-time system at steady state, is expressed as a function of the sensor measurements' frequencies. The trace of the weighted covariance matrix is selected as the optimization criterion, under linear constraints on the measuring frequency of each sensor and the cumulative rate of the extended Kalman filter updates. This formulation leads to a convex optimization problem (semidefinite program) whose solution provides the sensing frequencies, for each sensor on every robot, required in order to maximize the positioning accuracy of the group. Simulation and experimental results are presented that demonstrate the applicability of this method and provide insight into the properties of the resource-constrained cooperative localization problem
Data Driven Grammatical Error Detection in Transcripts of Children's Speech

We investigate grammatical error detection in spoken language, and present a data-driven method to train a dependency parser to automatically identify and label grammatical errors. This method is agnostic to the label set used, and the only manual annotations needed for training are grammatical error labels. We find that the proposed system is robust to disfluencies, so that a separate stage to elide disfluencies is not required. The proposed system outperforms two baseline systems on two different corpora that use different sets of error tags. It is able to identify utterances with grammatical errors with an F1-score as high as 0.623, as compared to a baseline F1 of 0.350 on the same data.
Health Information Technology: An Untapped Resource to Help Keep Patients Insured

The recent confluence of: (1) changing state and national insurance-related policies, and (2) the rapid growth in electronic health record (EHR) use, yields an unprecedented opportunity for patient-centered medical homes (PCMHs) and other primary care practices or care settings to use health information technology (HIT) and health information exchange (HIE) in novel ways to impact patient health. We propose that HIT is an untapped resource for supporting clinic-based efforts to help eligible patients obtain and maintain insurance coverage. This commentary presents a conceptual model and guiding principles for this idea. Additionally, it describes insurance support tools that could be used to conduct ‘inreach’ and ‘outreach’ with patients around health insurance, similar to how HIT is used to manage chronic disease and panels of patients, and to improve population health outcomes.
Internet Use in Uzbekistan: Developing a Methodology for Tracking Information Technology Implementation Success

This article reports on an ongoing investigation of Internet development in Central Asia. Begun in 2000, the research currently focuses on recent developments in Uzbekistan, including changes in legislation governing telecommunications. The results of two surveys conducted in November and December 2002 in Tashkent and Bukhara, Uzbekistan, are presented. These surveys of managers at Internet access points and information technology professionals provide a detailed picture of the current state of Internet infrastructure in Uzbekistan, particularly in contrast to official government figures. The article argues that effective survey research must incorporate an understanding of how culture, policy, and infrastructure affect patterns of Internet development.
Incorporating scientific knowledge into phenotype development: Penalized latent class regression

The field of psychiatric genetics is hampered by the lack of a clear taxonomy for disorders. Building on the work of Houseman and colleagues (Feature-specific penalized latent class analysis for genomic data. Harvard University Biostatistics Working Paper Series, Working Paper 22, 2005), we describe a penalized latent class regression aimed at allowing additional scientific information to influence the estimation of the measurement model, while retaining the standard assumption of non-differential measurement. In simulation studies, ridge and LASSO penalty functions improved the precision of estimates and, in some cases of differential measurement, also reduced bias. Class-specific penalization enhanced separation of latent classes with respect to covariates, but only in scenarios where there was a true separation. Penalization proved to be less computationally intensive than an analogous Bayesian analysis by a factor of 37. This methodology was then applied to data from normal elderly subjects from the Cache County Study on Memory and Aging. Addition of APO-E genotype and a number of baseline clinical covariates improved the dementia prediction utility of the latent classes; application of class-specific penalization improved precision while retaining that prediction utility. This methodology may be useful in scenarios with large numbers of collinear covariates or in certain cases where latent class model assumptions are violated. Investigation of novel penalty functions may prove fruitful in further refining psychiatric phenotypes.
Detection of small arms fire

A small arms fire detector, called Guardian, has been developed for Canadian peacemakers in hostile locations such as Bosnia. Guardian was developed at the MacDonald Dettwiler (MDD) Research Center and the Defense Research Establishment ValCartier (DREV) for the detection, localization, and classification of small arms fire. A description of small arms fire events and how these events are affected by the atmosphere are provided. The various detection techniques employed are described, along with conclusions on the most effective detection technique.
Optimizing spectral wave estimates with adjoint-based sensitivity maps

A discrete numerical adjoint has recently been de- veloped for the stochastic wave model SWAN. In the present study, this adjoint code is used to construct spectral sensitivity maps for two nearshore domains. The maps display the cor- relations of spectral energy levels throughout the domain with the observed energy levels at a selected location or region of interest (LOI/ROI), providing a full spectrum of values at all locations in the domain. We investigate the effectiveness of sensitivity maps based on significant wave height (Hs )i n determining alternate offshore instrument deployment sites when a chosen nearshore location or region is inaccessible. Wave and bathymetry datasets are employed from one shallower, small-scale domain (Duck, NC) and one deeper, larger-scale domain (San Diego, CA). The effects of seasonal changes in wave climate, errors in bathymetry, and multiple assimilation points on sensitivity map shapes and model per- formance are investigated. Model accuracy is evaluated by comparing spectral statistics as well as with an RMS skill score, which estimates a mean model-data error across all spectral bins. Results indicate that data assimilation from identified high-sensitivity alternate locations consistently im- proves model performance at nearshore LOIs, while assimila- tion from low-sensitivity locations results in lesser or no improvement. Use of sub-sampled or alongshore-averaged bathymetry has a domain-specific effect on model perfor- mance when assimilating from a high-sensitivity alternate location. When multiple alternate assimilation locations are used from areas of lower sensitivity, model performance may be worse than with a single, high-sensitivity assimilation point.
A Scalable Communication Runtime for Clouds

Leveraging cloud computing to acquire the necessary computation resources to scale out parallel applications is becoming common practice. However, many such applications also require communication and synchronization between processes. Although, commercial cloud platforms provide ready access to scalable compute and storage services, implementing communication and synchronization between cooperating processes and efficiently exchanging arbitrary size messages remains a challenge for application developers. In clouds, durable queues provide basic abstractions for communication. However, they are not sufficient for applications that require transferring arbitrary size messages or for applications that require higher level abstractions such as broadcast. Furthermore, direct socket based communication is susceptible to various fluctuations common in data center environments. We envision a solution to this problem that leverages scalable storage services, queues, and direct socket based communication. Publish/subscribe (pub/sub) is a well-known communication pattern that can achieve the above capabilities in a loosely coupled fashion, which is highly desirable in cloud environments where most services are asynchronous. In this paper, we describe the architecture of a pub/sub library implemented on a commercial cloud computing platform, which can be used to develop various parallel applications. We also present an evaluation of our implementation using both micro benchmarks and a real world application. Together, these demonstrate that our approach is both effective and scalable in performing communication and synchronization in cloud scale applications.
What makes a query difficult

This work tries to answer the question of what makes a query difficult. It addresses a novel model that captures the main components of a topic and the relationship between those components and topic difficulty. The three components of a topic are the textual expression describing the information need (the query or queries), the set of documents relevant to the topic (the Qrels), and the entire collection of documents. We show experimentally that topic difficulty strongly depends on the distances between these components. In the absence of knowledge about one of the model components, the model is still useful by approximating the missing component based on the other components. We demonstrate the applicability of the difficulty model for several uses such as predicting query difficulty, predicting the number of topic aspects expected to be covered by the search results, and analyzing the findability of a specific domain.
Active damping in HDD actuator

One of the limitations inherent in high-track-density hard disk drive design is the effect of actuator mechanical resonant modes on the head-positioning servo. The first servo bandwidth limiting mode is the so-called "butterfly mode," which is the major mode in the head mechanical transfer functions and can not be avoided through mechanical design. A special active damping technique has been developed for rotary actuators of 3-1/2" drives. With an additional sensor on the actuator and an external feedback loop, the butterfly mode can be damped and stiffened while the system stability is maintained. A theoretical system model, based on FEM, modal superposition and feedback control, is developed for analytical prediction of system stability and dynamics. Drive level experiments are conducted on actuators of two different designs, and show that the butterfly mode can be totally damped such that the gain of the head mechanical transfer function is close to 1/s/sup 2/. The end arm mode is also damped by about 8 dB for one actuator design. Servo improvement is also studied. It shows that the butterfly mode notch filter can be removed, and the phase margin can be improved by 7 degrees.
Self-disclosure mediates the effects of gender orientation and homophobia on the relationship quality of male same-sex friendships:

This study tested the degree to which self-disclosure mediates the effects of gender orientation and homophobia on relational satisfaction, closeness, and commitment in men’s same-sex friendships. Participants included 211 men from the southwest region of the US, who reported on either geographically close (n = 107) or long distance same-sex friendships (n = 104). Results indicated that self-disclosure mediates the positive effect of femininity on satisfaction, closeness, and commitment in men’s same-sex friendships. Self-disclosure also mediates the negative, indirect effects of homophobia on all three relational outcomes. Tests of structural invariance provided no evidence to suggest that the indirect effects of femininity and homophobia on all three relational outcomes vary as a function of geographic distance.
Using mean field annealing to solve anisotropic diffusion problems

Anisotropic diffusion is a powerful method for image feature extraction in which blurring is allowed to occur except at edges. Mean field annealing (MFA) is an image optimization technique which is used to find the best estimation of a blurred, noisy corrupted image. We show that MFA is versatile enough to be used for image feature extraction as well. Furthermore, the two major problems in anisotropic diffusion (white noise and geometric interpretation) can be solved by few modifications of the MFA equation. Finally, experiments and results are presented.
A numerical method of evaluating electromagnetic fields in multi-layer generalized anisotropic media

A transition matrix method commonly used in dealing with the problems of either plane-wave scattering from or the Green's function of multi-layered generalized anisotropic media is found inadequate in numerical implementation, when the waves are evanescent in the vertical direction of the structures. A recursive variable transformation method is developed, where all the exponentially-growing terms associated with exponential-matrix method are normalized. The new scheme is suitable for the numerical analysis of generalized anisotropic layers including ferrites, magneto-plasmas, chiral, and magneto-electric materials. Examples of the applications of the method are given. >
Tacit Understandings of Health Literacy: Interview and Survey Research With Health Journalists

This research offers both qualitative and quantitative data about how health journalists approach health literacy practically and conceptually. Using interviews with 20 writers and editors for magazines and newspapers coupled with a national survey ( N = 396), this analysis uncovers journalistic techniques and tacit theories for making information understandable. The journalists evince a basic understanding of how health literacy can be enhanced through certain story elements (such as nontechnical word use), but they also maintain false ideas about appropriate comprehension aides (such as statistics). Findings show that journalists struggle to maintain scientific credibility while accommodating different audience literacy levels. Journalists’ definitions of health literacy strategically carve out a place for their work as translators.
Displaced Children: Psychological Theory and Practice from the Field

On-going political crises around the world have created a sense of urgency among the international community about the need to provide psychosocial support to displaced children. But are we prepared to undertake this work? This paper examines the usefulness of available information, professional literature, and training models for the actualities of providing mental health care to children displaced by political conflict or civil war. It uses the author's field experience and research in Southeast Asia, Central America, and southern Africa as a basis for examining the efficacy of several interrelated issues: What are the different kinds of events that make war and political conflict a uniquely stressful experience for children? What has been learned about children's responses to this range of stressful and traumatic events? What are the implications of the above findings for mental health initiatives involving war and refugee populations? What are some of the wider political, social, and cultural issues confronted when attempting to implement psychosocial support programs for displaced populations?