cssi/SciSciGPT-SciSciNet huggingface dataset:
L70 life prediction for solid state lighting using Kalman Filter and Extended Kalman Filter based models

Solid-state lighting (SSL) luminaires containing light emitting diodes (LEDs) have the potential of seeing excessive temperatures when being transported across country or being stored in non-climate controlled warehouses. They are also being used in outdoor applications in desert environments that see little or no humidity but will experience extremely high temperatures during the day. This makes it important to increase our understanding of what effects high temperature exposure for a prolonged period of time will have on the usability and survivability of these devices. Traditional light sources “burn out” at end-of-life. For an incandescent bulb, the lamp life is defined by B50 life. However, the LEDs have no filament to “burn”. The LEDs continually degrade and the light output decreases eventually below useful levels causing failure. Presently, the TM-21 test standard is used to predict the L70 life of LEDs from LM-80 test data. Several failure mechanisms may be active in a LED at a single time causing lumen depreciation. The underlying TM-21 Model may not capture the failure physics in presence of multiple failure mechanisms. Correlation of lumen maintenance with underlying physics of degradation at system-level is needed. In this paper, Kalman Filter (KF) and Extended Kalman Filters (EKF) have been used to develop a 70-percent Lumen Maintenance Life Prediction Model for LEDs used in SSL luminaires. Ten-thousand hour LM-80 test data for various LEDs have been used for model development. System state at each future time has been computed based on the state space at preceding time step, system dynamics matrix, control vector, control matrix, measurement matrix, measured vector, process noise and measurement noise. The future state of the lumen depreciation has been estimated based on a second order Kalman Filter model and a Bayesian Framework. The measured state variable has been related to the underlying damage using physics-based models. Life prediction of L70 life for the LEDs used in SSL luminaires from KF and EKF based models have been compared with the TM-21 model predictions and experimental data.
Enterocolitis associated with Hirschsprung's disease: A clinical histopathological correlative study

Enterocolitis associated with Hirschsprung's disease (HEC) remains a major source of morbidity and even mortality, both before and after definitive surgical treatment. This study was undertaken to investigate whether histopathologic mucosal changes, in the absence of clinical manifestations of HEC, could predict the subsequent development of this complication. The clinical data and histopathology of 25 patients who eventually developed clinical HEC were compared with a control group of 25 age- and sex-matched patients with Hirschsprung's disease (HD) but with no clinical HEC either preoperatively or postoperatively. The histopathologic findings of tissue obtained by rectal biopsy or during laparotomy were graded from 0 to V according to severity and compared with the eventual clinical course. This study showed that (1) histopathologic findings of HEC appear to predict the clinical development, but not the severity, of future episodes of clinical HEC; (2) a histological grade of > or = II (> or = 2 crypt abscesses per high power field) should raise suspicion for subsequent occurrence of HEC, whereas a grade of > or = III (multiple crypt abscesses) places a child at high risk for development of clinical HEC; and (3) contrary to what is generally thought, histopathologic changes of HEC occur in both ganglionic and aganglionic segments. Based on these findings, it is recommended that histopathologic documentation of HEC and its grade should be an integral part of the tissue diagnosis of HD.
NONIMMEDIACY: ITS APPLICABILITY FOR MEASUREMENT

Summary.-This study examined the validity of the nonimmediacy concept as a potential measure of counselors' self-congruence. Variations in level of verbal nonimmediacy have been interpreted as implicit manifestations of positive and negative attitudes toward others. 53 counselor-trainees were requested ro write about two clients for whom they had very different feelings and indicate which client they liked better. Their written descriptions of each dienc were scored for verbal nonimmediacy according to the 9 categories of the nonimmediacy scale. The nonimmediacy concept was not confirmed with this particular sample. Analysis indicated virtually no mean differences berween nonimmediacy scores for more liked and less liked clients. This investigation raised the issue of the qualitative differences between the present and former subjects. Inherent psycholinguistic differences resulting from clinical rapport and objectivity may have accounted for these counselor-trainees' lack of discrimination of nonimmediacy with clients compared to other non-counseling populations. Counselors' self-congruence is reported to be an important function of the effectiveness of counseling and to have a significant effect on the counseling relationship and its outcome (Truax & Carkhuff, 1965; Truax, Carkhuff & Kodman, 1965; Dickenson gc Truax, 1966). It is most important for both counselors and their supervisors to be aware of the messages they express to their clients. Traditionally, investigators, in assessing the level and effect of counselors' congruence on the therapeutic relationship, have tended to focus on the nonverbal/verbal dichotomies of counselors' behavior or on counselors' self-reports or clients' ratings (Truax & Carkhuff, 1965; Berenson, Mitchell, & Laney, 1968; Hayden, 1970). While these studies tend to support the view that high levels of counselors' congruence are related to constructive changes in both therapeutic process and outcome, the methods selected for determining level of counselors' congruence appear to be highly subjective and inferential. Although gross discrepancies can be recognized by observing the inconsistencies between verbal and nonverbal aspects of behavior, other subtle indications of congruence may not be noticed by exclusively studying these features (Marsden, 1965). Significant nuances of genuineness may also be reflected by certain stylistic verbalizations implicitly conveyed by selection of particular words (Phillips & Smith, 1953; Marsden, 1965; Wiener & Mehrabian, 1968). Wiener and Mehrabian (1968) have identified criteria for what they have called nonimmediacy, that is, separation, nonidentification, or indirectness in the relationship between a communicator and the object of his communication in a verbal message. Essentially, the nine individual categories of the nonimmediacy
Cellular uptake of functional nanogels prepared by inverse miniemulsion ATRP with encapsulated proteins, carbohydrates, and gold nanoparticles.

Atom transfer radical polymerization (ATRP) was used to produce a versatile drug delivery system capable of encapsulating a range of molecules. Inverse miniemulsion ATRP permitted the synthesis of biocompatible and uniformly cross-linked poly(ethylene oxide)-based nanogels entrapping gold nanoparticles, bovine serum albumin, rhodamine B isothiocyanate-dextran, or fluoresceine isothiocyanate-dextran. These moieties were entrapped to validate several biological outcomes and to model delivery of range of molecules. Cellular uptake of nanogels was verified by transmission electron microscopy, gel electrophoresis, Western blotting, confocal microscopy, and flow cytometry. Fluorescent colocalization of nanogels with a fluorophore-conjugated antibody for clathrin indicated clathrin-mediated endocytosis. Furthermore, internalization of nanogels either with or without GRGDS cell attachment-mediating peptides was quantified using flow cytometry. After 45 min of incubation, the uptake of unmodified FITC-Dx-loaded na...
Translational implications of somatic genomics in acute myeloid leukaemia

Summary Acute myeloid leukaemia (AML) is caused by acquired somatic mutations in haemopoietic progenitors. Understanding of the genetic basis of the disease has greatly benefited from the use of DNA sequencing to identify novel disease alleles. Chromosomal aberrations are known to drive AML and are the mainstay of risk classification. Mutations in FLT3, NPM1 , and CEBPA provide prognostic information and have been integrated into clinical diagnostics and clinical practice. Comprehensive next-generation sequencing studies have given insight into AML pathogenesis. These insights are leading to refined prognostic stratification and suggest differentially tailored treatment based on integrated genetic profiles. Translation of comprehensive genetic analyses to the clinical setting is the next challenge, to enable genotype-specific therapies for patients with AML and other malignant disorders.
Power-optimal encoding for DRAM address bus (poster session)

This paper presents Pyramid code, an optimal code for transmitting sequential addresses over a DRAM bus. Constructed by finding an Eulerian cycle on a complete graph, this code is optimal for conventional DRAM in the sense that it minimizes the switching activity on the time-multiplexed address bus from CPU to DRAM. Experimental results on a large number of testbenches with different characteristics (i.e. sequential vs. random memory access behaviors) are reported and demonstrate a reduction of bus activity by as much as 50%.
Polio-virus adsorption from water onto silicate minerals

Abstract Six silicate minerals were investigated in batch study and one in a continuous flow column study for their ability to adsorb polio-virus I. From 64.2 × 10 4 to 89.5 × 10 4 PFU of the polio-viruses were adsorbed per mg of silicate mineral with differences shown for the various minerals. Extraneous organic matter competed for adsorption sites and also desorbed the virus. Under groundwater flow conditions the virus broke through the column earlier when the virus was adsorbed from a secondary effluent than when it was adsorbed from a clean water.
Assessing the head-to-toe physical examination skills of medical students

Second-year medical students performed a head-to-toe screening physical examination on trained patient instructors (PIs) as a high-stakes examination before beginning clinical clerkships. PIs completed a 138-item checklist and instructed the students in the proper performance of any incorrectly executed or omitted items. To assess the accuracy of the PI ratings, 'monitor' PIs watching the encounter by video completed checklists for 11 retests of failed students in 2001 and for 28 randomly selected encounters in 2002. Checklist-level discrepancies measured by mean absolute checklist difference were 8% in 2001 and 9% in 2002. Case-level mean difference between raters in 2002 was -2.9%. The inter-rater reliability for a single rater, estimated by the intra-class correlation coefficient for total encounter scores, was 0.95. The assessment and feedback were well received by the students. The Head-to-Toe examination provides a reliable assessment of a student's ability to carry out a complete screening physical examination. Patient instructors can be trained to acceptable accuracy and reliability despite the length and complexity of the exercise, and can provide effective feedback and teaching targeted to individual student deficiencies.
Potential for rooftop photovoltaics in Tokyo to replace nuclear capacity

In 2010, nuclear power accounted for 27% of electricity production in Japan. The March 2011 disaster at the Fukushima Daiichi power station resulted in the closure of all of Japan’s nuclear power plants and it remains an open question as to how many will reopen. Even before the loss of nuclear capacity, there were efforts in Japan to foster the use of renewable energy, including large scale solar power. Nuclear power plants in Japan provided more than just base-load by storing energy in large scale pumped hydroelectric storage systems, which was then released to provide some peaking capacity. If this storage were instead coupled to current generation rooftop solar systems in Tokyo, the combined system could help to meet peak requirements while at the same time providing 26.5% of the electricity Tokyo used to get from nuclear output, and do so 91% of the time. Data from a study of rooftop space and a 34 yr data set of average daily irradiance in the Tokyo metropolitan area were used. Using pumped hydroelectric storage with 5.6 times this rooftop area could completely provide for TEPCO’s nuclear capacity.
Factors Contributing to Ventriculostomy Infection

Objective Catheter-related infection remains a cause of morbidity in the use of external ventricular drains (EVDs). The aim of this retrospective single-center study was to assess the rate and factors related to ventriculostomy infections in the setting of the published literature. Methods Patients that underwent EVD placement in a single-center were retrospectively reviewed. Diagnosis, treatment, hospital course, and infection-related data were collected and analyzed in reference to ventriculitis rates. The protocols for EVD placement and maintenance were reviewed. Results Of 343 patients, 12 acquired an EVD infection. No significant differences existed between those with and without ventriculitis for age, sex, underlying diagnosis, or concomitant systemic infection. Although not significant, concomitant systemic infection existed in 4.7% of patients with ventriculitis versus 1.5% without. There was a significant difference in length of EVD placement in patients with ventriculitis (20.9 ± 15.3 days) versus those without (12.1 ± 18.2; P = 0.005). Coagulase-negative Staphylococcus and Staphylococcus aureus represented the most commonly associated pathogens. With an overall cumulative incidence of 3.5%, our rate compared favorably to the published literature (cumulative incidence 9.5%; range, 3.9%-23.2%). Conclusions Catheter-related infection remains an important complication of EVD placement. Of factors evaluated, length of time of catheter placement has the most notable relationship to infection incidence, suggesting that early drain removal should be a goal whenever medically appropriate.
Optimization of advanced reburning via modeling

The advanced reburning (AR) process is an integration of basic reburning and N-agent injection. The efficiency of AR depends on many factors, including the amount of the reburning fuel, the amount and location of N-agent injection, and spray characteristics. These parameters can be optimized via computer modeling. This paper describes a model that combines a detailed chemical mechanism with a simplified representation of mixing to describe the AR-lean process, a combination of basic reburning and N-agent coinjection with overfire air (OFA). The model takes into account mixing and thermal characteristics of a 300 KW combustion facility, which was used for experimental studies in support of model development. Modeling suggested that the efficiency of AR-lean strongly depends on amounts of the reburning fuel and N-agent, flue gas temperature at the point of OFA/N-agent injection, and N-agent evaporation time. The model described the most important features of AR-lean. Application of the model for optimization of AR-lean performance in the test facility was demonstrated.
The applicability of formol titration to the problem of end-group determinations in polynucleotides. A preliminary investigation.

Abstract The reaction between cytidine-5′-phosphate and formaldehyde has been investigated in order to determine whether or not titration in the presence of added formaldehyde can be used as a means of measuring the length of polynucleotide chains. In 2 M formaldehyde the reaction with the nucleotide comes to equilibrium within 40 min at room temperature. The extent to which the p K a of the cytidylic acid amino group is lowered by increasing formaldehyde concentrations has been measured. In potentiometric titration of cytidine-5′-phosphate in the presence of formadehyde, good agreement was obtained between the amount of phosphate calculated from the titration curve and that determined by phosphorus analysis. When four molar equivalents of cytidine were also present, however, (a mixture approximately equivalent to a solution of a penta-cytidylic acid), the best estimate of phosphate made from the titration curve exceeded the true value by about 19%.
Finite elements for the vibration of framed shear walls

A line finite-element model and a rectangular plane finite-element model are developed for the dynamic analysis of frames and shear walls, respectively. Each model is shown to be highly accurate and efficient in the frequency analyses through numerical examples. The nodal degrees of freedom of the two models are so assumed that they can be combined to form a composite structure of both frames and shear walls. An exact analytical solution for frequency analysis is obtained for a long rectangular panel stiffened with edge members. This solution is used to evaluate the finite-element solution and favorable agreement between the two methods is obtained. The versatility of the finite-elements is further shown by performing a frequency analysis of a typical framed shear wall.
Stent-graft migration: a reappraisal of analysis methods and proposed revised definition.

Purpose:To demonstrate the need for a radiographic definition of migration that accurately describes a specific failure mode of an aortic stent-graft.Methods:The diagnosis of endograft migration, a...
Exercise interventions for dementia and cognitive impairment: The Seattle Protocols

Research evidence strongly suggests that increased physical exercise may not only improve physical function in older adults but may also improve mood and slow the progression of cognitive decline. This paper describes a series of evidence-based interventions grounded in social-learning and gerontological theory that were designed to increase physical activity in persons with dementia and mild cognitive impairment. These programs, part of a collective termed the Seattle Protocols, are systematic, evidence-based approaches that are unique 1) in their focus on the importance of making regular exercise a pleasant activity, and 2) in teaching both cognitively impaired participants and their caregivers behavioral and problem-solving strategies for successfully establishing and maintaining realistic and pleasant exercise goals. While additional research is needed, initial findings from randomized controlled clinical trials are quite promising and suggest that the Seattle Protocols are both feasible and beneficial for community-residing individuals with a range of cognitive abilities and impairments.
Myelopathy resulting from invasive aspergillosis

Aspergillus, a ubiquitous mold, may cause invasive and fatal disease in immunosuppressed patients. Myelopathy is an uncommon presentation of invasive aspergillosis. This report describes three children admitted to the hospital between 1988 and 1995 who developed myelopathy as the first evidence of invasive aspergillosis. All had advanced leukemia and were profoundly immunosuppressed because of chemotherapy and broad-spectrum antibiotics. Weakness and pain presented first; then, sensation to pain and temperature was lost 2 to 6 days later, followed by complete myelopathy. Multiple brain lesions were seen on magnetic resonance imaging in one patient. Despite antifungal therapy, aspergillosis proved fatal within 1 month of onset of myelopathy in all patients. Physicians caring for immunocompromised children should be aware of myelopathy as a presentation of invasive aspergillosis.
Structural studies on ADP activation of mammalian glutamate dehydrogenase and the evolution of regulation

Glutamate dehydrogenase (GDH) is found in all organisms and catalyzes the reversible oxidative deamination of l-glutamate to 2-oxoglutarate. Unlike GDH from bacteria, mammalian GDH exhibits negative cooperativity with respect to coenzyme, activation by ADP, and inhibition by GTP. Presented here are the structures of apo bovine GDH, bovine GDH complexed with ADP, and the R463A mutant form of human GDH (huGDH) that is insensitive to ADP activation. In the absence of active site ligands, the catalytic cleft is in the open conformation, and the hexamers form long polymers in the crystal cell with more interactions than found in the abortive complex crystals. This is consistent with the fact that ADP promotes aggregation in solution. ADP is shown to bind to the second, inhibitory, NADH site yet causes activation. The β-phosphates of the bound ADP interact with R459 (R463 in huGDH) on the pivot helix. The structure of the ADP-resistant, R463A mutant of human GDH is identical to native GDH with the exception of ...
Investigation of the Effectiveness and Efficiency of the Exact Closure: Comparison With Industrial Closures and Spherical Harmonic Solutions

For stiffness predictions of short fiber reinforced polymer composites, it is essential to understand the orientation during processing. This is often performed through the equation of change of the fiber orientation tensor to simulate the fiber orientation during processing. Unfortunately this approach, while computationally efficient, requires the next higher ordered orientation tensor, thus requiring the use of a closure approximation. Many efforts have been made to develop closures to approximate the fourth-order orientation tensor in terms of the second order orientation tensor. Recently, Montgomery-Smith et al (2010) developed a pair of exact closures, one for systems with dilute suspensions and a second for dense suspensions, where the later works well for a variety of diffusion models. In this paper we compare the fiber orientation results of the Fast Exact Closure (FEC) for dense suspensions to that of the Spherical Harmonic solution, which although considered to be numerically exact does not readily lend itself to implementations in current industrial processing CFD codes. This paper focuses on a series of comparisons of material stiffness predictions between the FEC, current fitted closure models, and the spherical harmonics solution for a thin plate subjected to pure shear. Results for the select flows considered show the similarities between the current class of orthotropic fitted closures and that of the FEC. Although the results are similar between the fitted closures and the FEC, it is important to recognize that the Fast Exact Closure is formed without a fitting process. Consequently, the results are anticipated, in general, to be more robust in implementation.Copyright © 2010 by ASME
Neutron elastic scattering from 92, 96, 98, 100Mo between En = 7 and MeV

Abstract Elastic scattering of 7, 9, 11, 20 and 26 MeV neutrons from 92, 96, 98, 100Mo has been measured using the Ohio University time-of-flight facility. The measured yields were normalized with respect to the incident flux at 0°, to obtain absolute differential cross sections. These values were corrected for dead time, detector efficiency, flux attenuation, multiple scattering, finite geometry, neutron source anisotropy and compound elastic contributions. Relative uncertainties are estimated to be between 5%–10%, and the uncertainty in the normalization is estimated to be less than 5%. The data were used to obtain neutron optical model potential parameters. The energy and isospin dependence of the potential depths is presented. Coupled channel calculations are presented and compared with standard optical model calculations.
Growth factor responses of human arterial endothelial cells in vitro

Human arterial endothelial cells were cultured in vitro for up to 40 cumulative population doublings. Culture conditions similar to those required for long-term propagation of human umbilical vein endothelial cells were employed. These included fibronectin-coated culture vessels, 5 to 20% fetal bovine serum, endothelial cell growth factor, and heparin. Thoracic aorta endothelial cells were larger than iliac artery endothelial cells. Both cell types stained positively for Factor VIII antigen by immunofluorescence. A decrease in confluent density as a function of population doubling level was correlated with the appearance of large, senescent cells in the cultures. Serum growth factors to which the arterial endothelial cells responded included insulin, transferrin, epidermal growth factor, thrombin, and somatomedins. The effect of thrombin did not require the availabilty of the active site of the protease. The effect of the somatomedins was only seen in the presence of heparin. Neither platelet-derived growth factor nor hydrocortisone induced arteiral endothelial cell proliferation. These growth factor responses were also observed on the part of human umbilical vein endothelial cells.
Passive aircraft detection and noncooperative helicopter identification using extremely low-frequency (ELF) electric field sensors

A new type of passive electric field sensor concept that measures extremely low frequency (ELF) electric fields shows promise for detecting low-flying aircraft near, for example, airport runways or national borders. Because different types of aircraft (jets, airplanes, and helicopters) exhibit different signature characteristics, this type of sensor allows basic target classification. Additionally, helicopters generate ELF electric fields with strong spectral lines corresponding to the rotation of the main and tail rotors, so that the sensor can perform passive, noncooperative helicopter identification. Arrays of these sensors can be used to estimate aircraft speed, direction and height above the ground. We developed detailed 3-D models of an electrically charged helicopter and ground-based sensors, and simulated both target fields and sensor responses. We designed and built prototype sensors, which we used to collect data for various aircraft in the field; the collected signatures compare favorably with the simulated date. Our investigations to date indicate that these sensors naturally complement both fixed radars and distributed acoustic sensors; such a sensor could also be used alone as a low-cost and rugged alternative. This paper outlines the ELF sensor concept, the models, and the sensor hardware we used, and compares simulated and collected signatures.
Clinical system model for monitoring the physiological status of jaundice by extracting bilirubin components from skin diffuse reflectance spectra

Neonatal jaundice is a medical condition which occurs in newborns as a result of imbalance between the production and elimination of bilirubin. The excess bilirubin in the blood stream diffuses into the surrounding tissue leading to a yellowing of the skin. As the bilirubin levels rise in the blood stream, there is a continuous exchange between the extra vascular bilirubin and bilirubin in the blood stream and exposure to phototherapy also alters the process. Diffuse reflectance spectra from human skin contains physiological and structural information of human skin and nearby tissue. Blanching, a phenomenon in which a slight capillary closure pressure is applied to force the blood under the applied area. A diffuse reflectance spectrum has to be captured before and after blanching to isolate the intravascular and extra vascular bilirubin.A new mathematical model is proposed with extra vascular bilirubin concentration taken into consideration along with other optical parameters in defining the diffuse reflectance spectrum of human skin. Nonlinear Optimization and Genetic Algorithms have been adopted to extract the optical properties (bilirubin concentration) from reflectance spectrum of skin. Bilirubin components were extracted from simulated diffuse reflectance spectrum within an average error of 10%
Usefulness of financial ratios in a single industry

Abstract This paper reports the findings of a study on the relationship and ratio grouping of a well-published set of financial ratios within the context of a single, homogenous industry. The findings provide some insight into the validity of using single-industry ratio averages as standards to evaluate individual firm performance. Factor analysis was used to study the interrelationship among the ratios and to determine whether these ratios group in the “traditional” category of ratios suggested in the financial statement analysis literature. This analysis was followed by a cluster analysis of the composite ratios derived from the factor analysis to determine whether any consistent and stable statistical grouping of firms developed over time within the industry. These analyses were done for 72 companies for the period 1966–1975 using Dunn and Bradstreet ratios and Compustat data.
Value‐centered R&D organizations: Ten principles for characterizing, assessing, and managing value

The management of R&D organizations has received considerable attention in terms of the nature of the flow from research to development to deployed technology, as well as planning and managing this flow. R&D strategies, innovation funnels, and multistage decision processes, to name just a few constructs, have been articulated and elaborated. This article builds on this foundation to consider the nature of the value created by this process. An options-based approach is advocated for economic valuation of the products of R&D. Adoption and implementation of this approach is outlined in terms of ten principles for characterizing, assessing, and managing value. © 2004 Wiley Periodicals, Inc.† Syst Eng 7: 167–185, 2004
A Concise, Economical, and Diastereoselective Synthesis of Methyl DGJ Isopropylidene: An Iminocyclitol Molecule Core for Analogue Synthesis

A six-step synthesis of the title compound starting from l-lyxonolactone 2,3-isopropylidene (6) is described. The synthesis is achieved by conversion of 6 to the C5-triflate or C5-mesylate 7a or 7b and their displacement by sodium azide to yield the C5 azido compound 8. Addition of methylmagnesium bromide and catalytic hydrogenation during which the azide group is reduced to the amine followed by an intramolecular cyclization yields the imine 15. Concomitant reduction of the imine occurs stereoselectively to yield methyl DGJ isopropylidene (5) which is isolated via the succinic acid salt and its further neutralization with ammonia. It was found that changing the synthetic sequence, namely, instead of 7a → 8 → 9, the methylmagnesium bromide could be added first to the mesylate 7b, 7b → 11 followed by azide ion displacement 11 → 9. This modification proved advantageous from the viewpoint of cost, use of methanesulfonyl chloride rather than trifluoromethylsulfonyl chloride, ease of operation, and yield. Meth...
Conversion of Multicomponent Aerosol Size Distributions from Sectional to Modal Representations

A new method for converting a multicomponent aerosol size distribution from sectional to modal form is presented. The sectional distribution is fit with multiple lognormal modes using a nonlinear least-square regression that considers both the overall mass distribution and individual component distributions. The new method is compared to other conversion methods that assign sections to modes arbitrarily or that fit only the total mass distribution. Results of conversion tests using example distributions show that the multicomponent fit method is able to define a modal distribution that more accurately represents the original sectional distribution than do other methods. Total and component mass are conserved, the size, shape, and location of peaks match the original distribution, and modal compositions allocate components to the same size range as in the sectional representation. It is also able to convert distributions with relatively few size sections or where the size sections do not span the entire di...
Regression models for positive random variables

Abstract Many variables in economics, finance, and other disciplines are positive and nonnormally distributed. This paper considers a regression model with a specification of residuals which allows great flexibility for the distribution of the dependent variable. These distributions include the exponential, Weibull, gamma, lognormal, Burr, generalized gamma, generalized beta type 2, and others as special cases. The specification provides a general parametric form for modeling observed and unobserved heterogeneity as well as including the possibility of increasing, decreasing, constant, ∩- and ∪-shaped hazard functions. The models are used to study the distribution and hazard functions of welfare duration and the relationship between these spells and various demographic characteristics.
Defective Telomere Lagging Strand Synthesis in Cells Lacking WRN Helicase Activity

Cells from Werner syndrome patients are characterized by slow growth rates, premature senescence, accelerated telomere shortening rates, and genome instability. The syndrome is caused by the loss of the RecQ helicase WRN, but the underlying molecular mechanism is unclear. Here we report that cells lacking WRN exhibit deletion of telomeres from single sister chromatids. Only telomeres replicated by lagging strand synthesis were affected, and prevention of loss of individual telomeres was dependent on the helicase activity of WRN. Telomere loss could be counteracted by telomerase activity. We propose that WRN is necessary for efficient replication of G-rich telomeric DNA, preventing telomere dysfunction and consequent genomic instability.
Women’s Attitudes Toward Biomedical Technology for Infertility: The Case for Technological Salience

Research has consistently revealed gender differences in attitudes toward science and technology. One explanation is that women are more personally affected by particular technologies (e.g., biomedical interventions), so they consider them differently. However, not all women universally experience biomedical technologies. We use the concept of technological salience to address how differences in subjective implications of a technology might explain differences in women’s attitudes toward biotechnology. In a sample of U.S. women from the National Survey of Fertility Barriers, we examine how women with and without a biomedical barrier to fertility evaluate biotechnology for infertility, which, we argue, reflects differences in technological salience. For women with a biomedical barrier, various experiences, beliefs, and values impacted their attitudes; yet, most of these did not affect attitudes if women had not experienced a fertility barrier. Results suggest that technological salience contextualizes wome...
Reducing capacity fade in vanadium redox flow batteries by altering charging and discharging currents

Abstract In this study, the operation of a vanadium redox flow battery (VRFB) under asymmetric current conditions (i.e., different current densities during charge and discharge) was investigated as a technique to reduce its capacity loss. Two different membrane types (a convection-dominated membrane and a diffusion-dominated membrane) were analyzed. In these analyses, the charging current density was varied while the discharging current was held constant. For both membranes, it was found that increasing the charging current decreases the net convective crossover of vanadium ions, which reduces the capacity loss of the battery. When the tested membranes were compared, the improvement in capacity retention was found to be larger for the diffusion-dominated membrane (12.4%) as compared to the convection-dominated membrane (7.1%). The higher capacity retention in the diffusion-dominated membrane was attributed to the reduction in the cycling time (and hence, suppressed contribution of diffusion) due to the increased charging current. While asymmetric current operation helps reduce capacity loss, it comes at the expense of a reduction in the voltage efficiencies. Increasing the charging current was found to increase the ohmic losses, which lead to a decrease of 6% and 4.3% in the voltage efficiencies of the convection-dominated and diffusion-dominated membranes, respectively.
Physical and Biological Properties of Cyclopolymers Related to DIVEMA (“Pyran Copolymer”)

A series of copolymers related in structure to the 1:2 alternating cyclocopolymer of divinyl ether and maleic anhydride (DIVEMA) have been shown to possess antitumor properties. The synthesis and structures of these copolymers are discussed, and their effectiveness as antitumor agents is presented. Certain of the copolymers have been prepared in controlled molecular weight ranges using chain transfer agents, and the resultant copolymers finally fractionated via use of solvent-nonsolvent systems. These samples of narrow molecular weight distribution have been evaluated for their antitumor properties and have been found to be quite effective.
INFORMATION-THEORETIC ANALYSIS OF RANDOMIZATION AND SPONTANEOUS ACTIVITY

Summary.-The purpose of the study was to determine the informationtheoretic mesure of redundancy for a sequence randomized by subjects and for a sequence spontaneously producd by subjects. It was hypothesized on the basis of previous findings wich self-paced tasks that redundancy in the sequence under conditions of spontaneous activity would be higher than under conditions of rarrdomization. 28 subjects were instructed to randomize three alternative push-buaon responses or to produce a spontaneous sequence of such responses. Both tasks were paced by a metronome and performed twice. As expected, redundancy was significantly higher in the condition of spontaneous activity. Redundancy was also higher in the second task and seemed to be higher in paced tasks as compared with previously published data obtained with the use of self-paced tasks. The latter effect was interpreted as a function of a superimposed activity of synchronization of responses with a time marker. Higher redundancy of spontaneously produced sequences was said to be firmly established and independent of pacing or nonpacing of responses. Warren and Morin (1965), Slak, Hirsch, and Syrja (1979), and Wagenaar (1972), among others, have demonstrated that human subjects are not capable of generating a random sequence. Slak and Hirsch (1974) as well as Warren and Morin (1965) showed that as the number of alternative items to be randomized increases, it becomes more difficult to randomize the sequence. Mittenecker (1960) provided evidence that inability to randomize is correlated wich neuroticism and psychoticism. Evans and Graham (1980) suggested chat the random-number-generation task is a sensitive measure of deployment of attention on performance tasks and in learning complex skills. Information theory provides the most adequate measure of randomness or nonrandomness. Randomness is simply relative entropy (R,) or the average amount of information produced in a sequence as a proportion of the maximum possible amount of information. Nonrandomness is defined as redundancy (C,) which is further defined as C, = 1 - R, where 0 4 R,, L 1 and 0 4 C, 4 1. The value n represents the number of sequence elements used as a basis for computation of redundancy, a measure which takes into account all aspects of nonrandomness for that sequence length. Attneave ( 1954) and Slak ( 1977) give other computational details for determination of relative entropy and redundancy. Wagenaar's ( 1972) review shows that
Song repertoires in the red-winged blackbird (Agelaius phoeniceus): A test of the Beau Geste hypothesis

Song repertoires in the red-winged blackbird (Agelaius phoeniceus) were studied to test the hypothesis that song repertoires have evolved to mimic high density. Results were consistent with predictions of this hypothesis. (1) Song types within a repertoire were as variable as those sung by different males. (2) Males often switched song type when they switched perch. (3) Males with large repertoires sang at faster rates than those with small repertoires, but repertoire size did not affect bout length or bout rate. (4) Rate of habituation was a function of repertoire size. (5) Empty territories occupied by speakers broadcasting song repertoires were more successfully defended than those occupied by speakers broadcasting single song types. These results are also consistent with the hypothesis that song repertoires function to signal the status of the singer. In many species of birds, individual males sing repertoires of distinct, but apparently redundant, versions of the species-typical song. The Beau Geste hypothesis (Krebs 1977a, 1978) proposes that such song repertories have evolved because non-territorial males seeking breeding territories attempt to avoid densely occupied areas, and multiple song types enable territorial singers to mimic high density. The hypothesis was pro- posed to provide a functional explanation for listener habituation and suggests that non- territorial males settle in low-density areas be- cause they habituate rapidly in response to small numbers of song types. However, density assess- ment could occur by any process that allows listeners to count the number of song types they hear. Natural selection is presumed to have favoured the evolution of song repertoires and related behaviour that enable one male to create the impression that his territory is occupied by several singers. The Beau Geste hypothesis was formulated to explain the evolution of relatively small reper- toires (from 2 to 20 song types/individual) of song types carrying identical messages. Species with such small repertoires are typically 'discontinuous' singers (Hartshorne 1956, 1973) that organize their songs into bouts, each con- sisting of successive renditions of one song type. The hypothesis is most likely to apply to species in which singing males are difficult to see, or at least to species in which vocal signalling is the primary component of territory defence. The hypothesis makes the following predic- tions (Krebs 1977a): (1) Song types within a
Theater Nuclear and Conventional Force Improvements

This article discusses the modernization of NATO conventional and long-range intermediate nuclear forces. Depending upon the perspective chosen, one can logically defend improvements in either, or both, long-range theater nuclear and conventional forces. Such choices cannot be removed from the divergence in priorities and perspectives between the United States and its European NATO allies on these issues. Although there is no single "European" view, central tendencies pull Europeans away from conventional force improvements and toward increased reliance on nuclear deterrence and retaliation.
Teleport messaging for distributed stream programs

In this paper, we develop a new language construct to address one of the pitfalls of parallel programming: precise handling of events across parallel components. The construct, termed teleport messaging, uses data dependences between components to provide a common notion of time in a parallel system. Our work is done in the context of the Synchronous Dataflow (SDF) model, in which computation is expressed as a graph of independent components (or actors) that communicate in regular patterns over data channels. We leverage the static properties of SDF to compute a stream dependence function, SDEP, that compactly describes the ordering constraints between actor executions.Teleport messaging utilizes SDEP to provide powerful and precise event handling. For example, an actor A can specify that an event should be processed by a downstream actor B as soon as B sees the "effects" of the current execution of A. We argue that teleport messaging improves readability and robustness over existing practices. We have implemented messaging as part of the StreamIt compiler, with a backend for a cluster of workstations. As teleport messaging exposes optimization opportunities to the compiler, it also results in a 49% performance improvement for a software radio benchmark.
The Politics of Muslims in America

This article analyzes political participation and the attitudes of Muslim-Americans. Assessing national patterns, the first part highlights several regression models, discerning the impact of race/ethnicity, gender, foreign born status, age, and education on political activity and attitudes. I also compare changes in voting patterns among respondents between the 2000 and 2004 elections. The second half is based on in-depth interviews of Muslims from St. Louis, Missouri, probing more directly particular shifts in views and participation since September 11. Among the national sample, South Asians and Middle Easterners largely supported Republican George W. Bush in 2000, while African-Americans voted for Democrat Al Gore. However, by 2004, race and ethnicity were no longer statistically significant factors dividing the Muslim vote; instead, support largely went to Democrat John Kerry. Changes in voting patterns between 2000 and 2004 were also evident in the St. Louis sample of South Asians and Middle Easterners. They generally cited unfavorable views of Muslim treatment both at home and abroad since the War on Terror began as major reasons for these changes. Partisan and voting shifts were not evident among African-Americans, who have been consistent Democrats. However, many African-Americans in addition to Middle Easterners and South Asians reported heightened interest in politics and similar changes since September 11. Only Bosnians, who are relatively new to the United States, report few changes. This is largely because they have yet to develop firm political identities. Among both samples, Muslim-Americans generally exhibit high rates of participation in various political activities, many reporting increasing interest and involvement since September 11. Therefore, regardless of the hardships they may currently feel, Muslim-Americans are not hiding in the shadows but are fully participating in the political sphere.
Implantable transvenous cardioverter-defibrillators.

BACKGROUNDImplantable transvenous cardioverter-defibrillators offer a significant opportunity to decrease procedural morbidity and medical costs in the care of patients with life-threatening ventricular arrhythmias who otherwise would have required a sternotomy or thoracotomy for device insertion. The purpose of this study was to examine prospectively the safety, efficacy, and limitations associated with the use of a transvenously implanted, tiered-therapy cardioverter-defibrillator with antitachycardia pacing function in a consecutive population of 84 ventricular fibrillation (VF) and sustained ventricular tachycardia (VT) survivors.METHODS AND RESULTSThe index arrhythmia promoting transvenous cardioverter-defibrillator implantation was VF in 41 patients, VT in 27, and both VF and VT in 16. In each patient, transvenous defibrillation via a coronary sinus, a right ventricular, a superior vena caval, and/or a subcutaneous chest patch lead system was attempted. The pulsing methods used include two-electrode...
The management of chronic idiopathic urticaria

The cause of chronic urticaria is often elusive and may be multifactorial. Routine laboratory investigations, other than a blood count and erythrocyte sedimentation rate (ESR), are usually unhelpful. Non-specific precipitants, such as food colours and additives and non-steroidal anti-inflammatory drugs, should be avoided if possible. Heat, exercise, stress and alcohol consumption should be minimized. H, receptor blocking antihistamines are the mainstay of drug therapy. A non-sedating antihistamine may usefully be combined with a sedating antihistamine at night if sleep is disturbed. The addition of an H, receptor antagonist may be beneficial. Oral terbutaline and nifedipine can sometimes be effective when taken with antihistamines, probably by inhibiting degranulation. Treatment with antifibrinolytic agents and attenuated androgens should be reserved for severe refractory cases that have not responded to antihistamines. Systemic corticosteroids and adrenaline should only be used for acute disabling attack...