cssi/SciSciGPT-SciSciNet huggingface dataset:
Physician Attitudes Toward End-Stage Heart Failure: A National Survey

Abstract Background Despite recent improvements in medical therapies, heart failure remains a prevalent condition that places significant burdens on providers, patients, and families. However, there is a paucity of data published describing physician beliefs about heart failure management, especially in its advanced stages. Methods In order to better understand physician decision-making in end-stage heart failure, we used a stratified random sampling of physicians obtained from the Master File of the American Medical Association to survey cardiologists (n=600), geriatricians (n=250), and internists/family practitioners (n=600). Results Response rate was 59.6% (highest among geriatricians). The vast majority (>90%) of respondents cited similarities between the clinical trajectory of end-stage heart failure and lung cancer or chronic obstructive pulmonary disease; however, only 15.7% stated that they could predict death at 6 months "most of the time" or "always." Inpatient volume was a predictor of confidence in predicting mortality (odds ratio=1.38, 95% confidence interval, 1.36-1.40). Less than one quarter of respondents formally measure quality of life. The experience with deactivation of implantable cardioverter defibrillators was limited: 59.8% of cardiologists, 88.0% of geriatricians, and 95.1% of internal medicine/family practice physicians have had 2 or fewer conversations with patients and families about this option. Conclusions Significant gaps in knowledge about and experience with end-stage heart failure exist among a large proportion of physicians. The growing prevalence and highly symptomatic nature of heart failure highlight the need to further evaluate and improve the way in which care is delivered to patients dying from the disease.
Multiple growth factors regulate coronary embryonic vasculogenesis.

Mechanisms regulating coronary vascularization are not well understood. To test hypotheses regarding the influence of key growth factors and their interactions, we studied vascular tube formation (vasculogenesis) in collagen gels onto which quail embryonic ventricles were placed and incubated in the presence of growth factors or inhibitors. Vasculogenesis in this model is dependent on tyrosine kinase receptors, since tube formation was totally blocked by genestein. Tube formation was attenuated when anti-bFGF or anti-VEGF neutralizing antibodies were added to the medium and nearly completely inhibited when the both were added. The attenuation associated with anti-VEGF was due primarily to a decrease in assembly of endothelial cells, while that associated with bFGF was primarily due to a reduction in endothelial cells. Soluble tie-2, the receptor for angiopoietins, also had an inhibitory effect and, when added with either anti-bFGF or anti-VEGF, markedly attenuated tube formation. At optimal doses, tube formation was enhanced 6.5-fold by bFGF and 2.5-fold by VEGF over the controls. Each of these growth factors was dependent upon the other for optimal induction of tube formation, since neutralizing antibodies to one markedly reduced the potency of the other. VEGF potency was also markedly reduced when soluble tie-2 was added to the medium. Tube formation was virtually totally blocked by exogenous TGF-β at doses > 1 ng/ml, while neutralizing TGF-β antibodies enhanced tube formation 2-fold in the 30 ng–30 μg range. These data provide the first documentation of multiple growth factor regulation of coronary tube formation. © 2001 Wiley-Liss, Inc.
Nuclear polarization in muonic atoms of deformed nuclei

Abstract The treatment of nuclear polarization correction in muonic atoms belonging to deformed nuclei is analyzed. The geometrical factors involved are expanded into a series of multipoles and the exact expansion coefficients are calculated. It is shown that, using reasonable assumptions about the nuclear spectrum, the nuclear polarization correction may be expressed as a shift of all hyperfine components plus a renormalization of the even multipole hyperfine interaction constants. All nuclear excited states contribute to the shift, but the ground-state rotational band gives an over-whelming contribution to the multipole moment renormalization. The effect of the ground-state band is analyzed in detail. The radial coefficients are calculated and an approximate formula, applicable over a broad range of atomic numbers and deformations, is obtained. By comparing our results with exact calculations we conclude that this part of the nuclear polarization correction may be calculated with accuracy better than 10 %.
An architecture for integrated commercial building demand response

Enthusiasm for commercial demand response (DR) has inspired research efforts to create new building electric load control frameworks. In this paper we introduce a software architecture for an integrated building control system, the Central Load Shed Coordinator (CLSC). The CLSC provides functional control over three building systems which are large power consumers: lighting, HVAC, and plug loads. The system acts upon external demand response signals to meet load-shed criteria, while minimizing occupant inconvenience. In this paper, we present the purpose and relevant characteristics of this architecture. In addition, we discuss its deployment in a UC Berkeley building and present results from preliminary testing.
FARE: A framework for benchmarking reliability of cyber-physical systems

A cyber-physical system (CPS) is a system featuring a tight combination of, and coordination between, the system's computational and physical elements. System reliability is a critical requirement of cyber-physical systems. An unreliable CPS often leads to system malfunctions, service disruptions, financial losses and even human life. Improving CPS reliability requires an objective measurement, estimation and comparison of the CPS system reliability. This paper describes FARE (Failure Analysis and Reliability Estimation), a framework for benchmarking reliability of cyber-physical systems. Some prior researches have proposed reliability benchmark for some specific CPS such as wind power plant and wireless sensor networks. There were also some prior researches on the components of CPS such as software and some specific hardware. But according to the best of our knowledge, there isn't any reliability benchmark framework for CPS in general. FARE framework provides a CPS reliability model, a set of methods and metrics on the evaluation environment selection, failure analysis and reliability estimation for benchmarking CPS reliability. It not only provides a retrospect evaluation and estimation of the CPS system reliability using the past data, but also provides a mechanism for continuous monitoring and evaluation of CPS reliability for runtime enhancement. The framework is extensible for accommodating new reliability measurement techniques and metrics. It is also generic and applicable to a wide range of CPS applications. For empirical study, we applied the FARE framework on a smart building management system for a large commercial building in New York City. Our experiments showed that FARE is easy to implement, accurate for comparison and can be used for building useful industry benchmarks and standards after accumulating enough data.
What is constructive empiricism

L'A. tente de definir l'empirisme constructif de B. van Fraassen a partir d'un travail hermeneutique sur ses ecrits, ce qui l'amene a depasser l'opposition realisme/antirealisme, et a deceler la raison de son rejet metaphysique pre-kantien de l'experience
Experimental characterization of electrospinning: the electrically forced jet and instabilities

In the electrospinning process, polymer fibers with submicron-scale diameters are formed by subjecting a fluid jet to a high electric field. We report an experimental investigation of the electrically forced jet and its instabilities. The results are interpreted within the framework of a recently developed theory for electrified fluid jets. We find that the process can be described by a small set of operating parameters and summarized through the use of operating diagrams of electric field versus flow rate. In addition, the jet current is related to the net charge density and found to depend on the fluid properties, the applied electric field and the equipment configuration. The net charge density appears to be relatively insensitive to the flow rate, at least for high flow rates. The experiments reveal that a key process in the formation of submicron-scale solid fibers is a convective instability, the rapidly whipping jet. The dependence of this instability on electric field and flow rate, and the exponential nature of its growth rate are in accord with the theory.
Finite-difference time-domain studies of light transmission through nanohole structures

We present theoretical studies on the transmission of light through subwavelength, circular apertures surrounded by circular groove structures. Finite-difference time-domain equations in cylindrical coordinates are provided for both dispersive materials and electrical conductors. The nanohole systems are composed of a circular hole in a slab, that is encircled by sinusoidal grooves defined by a period and depth. Light transmission is found to be extremely sensitive to the hole size, groove period, and groove depth. We determine a set of groove parameters that optimize transmission. Enhancements in transmission by approximately a factor of four can be achieved for silver in the visible when compared to the light incident upon the hole. These results may find utility in the design of nanoscale light manipulating devices.
SimDL: a model ontology driven digital library for simulation systems

We propose a digital library design to support epidemic and public health simulation experiments in which model ontologies direct collection organization, user interface construction, and discovery. We have developed a SimDL instantiation of the ontological design tailored for a typical experimentation workflow. SimDL relies on an XML Schema description of a simulation model to form a domain and model specific ontology. We show this approach useful in building digital libraries to support collaborative simulation efforts.
Potential scattering with confined channels

Abstract We introduce a class of nonrelativistic multichannel potential scattering models which are characterized by the simultaneous presence of and communication between two distinct types of channels: First, ordinary two-particle scattering channels, the Hamiltonian for which has an absolutely continuous spectrum on the positive real energy axis and perhaps a finite number of negative energy bound states; second, permanently confined channels (like those of the quark model), the Hamiltonian for which has only a point spectrum with an accumulation point at E = + ∞. These two types of channels are connected in the full Hamiltonian H for the multichannel system by off-diagonal local potentials which satisfy suitable smoothness and integrability conditions. The scattering theory of such systems is developed and, under certain general restrictions on the potentials, the following properties are rigorously established: (1) Asymptotic completeness; i.e., the generalized wave operators exist and are complete, and the S-matrix is a unitary operator in the scattering channels. The S-matrix has nonzero matrix elements only in the scattering channels. (2) The spectrum of the Hamiltonian H consists of 3 parts, namely, a finite number of negative energy eigenvalues, a discrete set of positive energy eigenvalues with only possible accumulation point at E = + ∞, and an absolutely continuous spectrum on the remainder of the positive real energy axis. To each eigenvalue, positive or negative, corresponds a finite number of orthonormal eigenvectors, the bound states of H ; and to each positive energy there corresponds a unique bounded solution, the distorted plane wave, to the time-independent Schrodinger equation. (3) There is an eigenfunction expansion associated with H in which enter only the bound-state eigenvectors and the distorted plane wave eigenfunctions. (4) The subspaces of discontinuity and absolute continuity of H are orthogonal complements to each other. In addition the scattering amplitude for these models is constructed and shown to be related to the S-matrix in the usual way. Both the S-matrix and the scattering amplitude are well defined and continuous at the positive boundstate energies.
The incorporation of radioactive proline into cultured cells. Interpretations based on radioautography and electron microscopy.

Cultured carrot explants, stimulated to grow rapidly in a medium containing coconut milk, were labeled with radioactive proline. After an initial period of absorption (8 hr for proline-3H; 24 hr for proline-14C) the tissue was allowed to grow for a further period of 6 days in a similar medium free from the radioactivity. Samples were prepared for electron microscopy and radioautography at the end of the absorption period and also after the further growth. The distribution of the products from the radioactive proline in the cells is shown by high-resolution radioautography and is rendered quantitative for the different regions of the cells. The results show that the combined label, which was present in the form of proline and the hydroxyproline derived from it, was all in the protoplasm, not in the cell walls. Any combined label that appeared to be over the cell walls is shown to be due to scatter from adjacent cytoplasmic sites. Initially the radioactivity was concentrated in nuclei, even more so in nucleoli, but it subsequently appeared throughout the ground cytoplasm and was also concentrated in the plastids. The significance of these observations for the general concept of a plant cell wall protein and for the special problem of growth induction in otherwise quiescent cells is discussed.
Diffusion flame extinction at small stretch rates: The mechanism of radiative loss

Abstract A theoretical analysis of diffusion flame extinction in the stagnation point region of a condensed fuel has been made including radiative heat loss from the fuel surface. In addition to the blowoff limit normally found when flame stretch rate is large, an extinction limit has been identified when the flame stretch rate becomes sufficiently small. This limit occurs as a result of flame temperature reduction when the rate of radiative loss becomes substantial compared with the rate of combustion heat release. A flammability map using oxygen mass fraction and stretch rate as coordinates shows that the extinction boundary consists of a blowoff and a radiative extinction branch. The merging point of the two branches defines a fundamental low oxygen flammability limit.
Recent developments in HgCdTe and HgZnTe growth from Te solutions

Abstract Growth of HgCdTe by liquid phase epitaxy (LPE) from Te-rich solutions has become a widely used approach to produce large-area films with good crystalline quality. This approach offers several advantages, namely, a low Hg overpressure, simplicity of growth chamber design, and reduced solute depletion from the melt. This paper briefly reviews some of the recent progress in growing LPE from Te rich melts and compares it with alternative epitaxial growth techniques. In addition, it will address doping HgCdTe LPE with group Va impurities and growth of HgZnTe as a possible emerging alternative to HgCdTe.
Differentiation of multipotent vascular stem cells contributes to vascular diseases

It is generally accepted that the de-differentiation of smooth muscle cells, from the contractile to the proliferative/synthetic phenotype, has an important role during vascular remodelling and diseases. Here we provide evidence that challenges this theory. We identify a new type of stem cell in the blood vessel wall, named multipotent vascular stem cells. Multipotent vascular stem cells express markers, including Sox17, Sox10 and S100β, are cloneable, have telomerase activity, and can differentiate into neural cells and mesenchymal stem cell-like cells that subsequently differentiate into smooth muscle cells. On the other hand, we perform lineage tracing with smooth muscle myosin heavy chain as a marker and find that multipotent vascular stem cells and proliferative or synthetic smooth muscle cells do not arise from the de-differentiation of mature smooth muscle cells. In response to vascular injuries, multipotent vascular stem cells, instead of smooth muscle cells, become proliferative, and differentiate into smooth muscle cells and chondrogenic cells, thus contributing to vascular remodelling and neointimal hyperplasia. These findings support a new hypothesis that the differentiation of multipotent vascular stem cells, rather than the de-differentiation of smooth muscle cells, contributes to vascular remodelling and diseases.
Federal Polices Influence Access to Primary Care and Nurse Practitioner Workforce

Although most nurse practitioners (NPs) are aware of state-level regulations that influence practice, many are unaware of the ways that federal policies affect NP workforce supply and the delivery of primary care. In this investigation we provide an overview of federal initiatives enacted through the Patient Protection and Affordable Care Act that impact the NP workforce. We explore how the law supports NP workforce supply and settings in which NPs provide care. We then describe challenges that may prevent full utilization of the NP workforce. Examining both federal policies and state-level regulations is essential to achieving an increased NP workforce supply and improved access to care.
Unconfined vapor-cloud explosions—An overview

The explosion of unconfined vapor clouds produced by the dispersion of flammable liquidor vapor spills is becoming a serious problem, mainly because of the increased size of the spills in recent years. This paper surveys accidental explosions that have occurred over the past 40 years and also evaluates recent research efforts which pertain to the dispersion and explosion of large vapor clouds. The major problem appears to be the lack of a fundamental understanding of a transient flame-buoyancy interaction during combustion of the cloud, since both accidental and deliberate explosions have exhibited over-all flame propagation rates almost an order of magnitude above the values one would expect without the consideration of buoyancy effects. Other problems which are discussed include, 1) the initial dispersion of the cloud, 2) the prediction of blast effects, and 3) the question of direct initiation of detonation. Recommendations for future research are given.
Corporate Cash Policy and How to Manage it with Stock Repurchases

At the end of 2004 total U.S. corporate cash holdings reached an all-time high of just under $2 trillion—an amount equal to roughly 15% of the total U.S. GDP. And during the past 25 years, average cash holdings have jumped from 10% to 23% of total corporate assets. But at the same time their levels of cash have risen, U.S. companies have paid out dramatically increasing amounts of cash to buy back shares. This article addresses the following questions: What accounts for the dramatic increase in the average level of corporate cash holdings since 1980? And why do some companies keep so much cash (with one fourth of U.S. firms holding cash amounting to at least 36% of total assets) while others have so little (with another quarter having less than 3%)? Why do companies pay out excess cash in the form of stock repurchases (rather than, say, dividends), and what explains the significant increase in repurchases (both in absolute terms and relative to dividends) over time? The author begins by arguing that cash reserves provide companies with a buffer against possible shortfalls in operating profits—one that, especially during periods of financial trouble, can be used to avoid financial distress or provide funding for promising projects that might otherwise have to be put off. Such buffers are particularly valuable in the case of smaller, riskier companies with lots of growth opportunities and limited access to capital markets. And the dramatic increase in corporate cash holdings between 1980 and the present can be attributed mainly to an increase in the risk of publicly traded companies—an increase in risk that reflects in part a general increase in competition, but also a notable change over time in the kinds of companies (smaller, newer, less profitable, non-dividend paying firms) that have chosen to go public. At the other end of the corporate spectrum are large, relatively mature companies with limited growth opportunities. Although such companies tend to produce considerable free cash flow, they also tend to retain relatively small amounts of cash (as a percentage of total assets), in part because of shareholder concern about the corporate “free cash flow problem”—the well-documented tendency of such companies to destroy value through overpriced (often diversifying) acquisitions and other misguided attempts to pursue growth at the expense of profitability. For companies with highly predictable earnings and investment plans, dividends provide one means of addressing the free cash flow problem. But for companies with more variable earnings and less predictable reinvestment, open-market stock repurchases provide a more flexible means of distributing cash to shareholders. Unlike the corporate “commitment” implied by dividend payments, an open market stock repurchase program creates what amounts to an option but not an obligation to distribute funds. The value of such flexibility, which increases during periods of increased risk and uncertainty, explains much of the apparent substitution of repurchases for dividends in recent years.
Order-restricted inference for monotone trend alternatives in contigency tables

For many contingency tables with ordered categories, one expects a monotone association yet one may prefer not to assume a particular parametric model. This article presents estimation and likelihood-ratio testing for various monotone trend alternatives to independence in such tables. The alternatives are characterized by non-negative values for four types of log odds ratios for ordinal data: Local, global, cumulative, and continuation-ratio. When monotone association exists according to all these criteria, tests based on local odds ratios are asymptotically more powerful than tests with odds ratios having greater aggregation. Sampling distributions of these test statistics are awkward even for large samples, but it is straightforward to simulate their exact distributions and provide nearly exact P-values. Extensions are given to order-restricted inference about conditional association in a three-way contingency table and about marginal distributions of a square contingency table. The analyses presented here have the advantage of weaker assumptions than those based on parametric models, but research is needed to study conditions under which they are more or less powerful than the model-based methods.
AUTOMATION OF METHODS FOR THE DETERMINATION OF SERUM PHOSPHORUS.

Abstract Three procedures for the automated determination of serum inorganic phosphate have been described. For each of these technics, an accurate manual variation is available when necessary. A set of recoveries was made to indicate the comparable nature of the three automated procedures. A second set of recoveries showed that the two manual procedures proposed yielded results which were similar to presently acceptable methods, and that one of the three comparable automated technics is equally as accurate as the manual technic. This interchangeable technic of comparison of the three automated and manual procedures to each other and to acceptable manual methods shows that the proposed technics are analytically acceptable.
The Consummate Professor

The goal of today's upwardly striving colleges and universities is to attract, develop, and retain faculty who are committed to excellence in teaching and research. Through them, the institution achieves its reputation, maintains its intellectual vigor, and continues to grow. Faculty members are expected to be great teachers, expert researchers, wise advisors and counselors (ready to help solve the problems of the students, the university, their communities, the state, and the nation) and, in all of these areas, to be model leaders. When we find the person who answers this description, we will have found the consummate professor. Does she or he exist? Or is it an impossible dream?
A comparison of electrical, computer, and chemical engineering facultys' progressions through the innovation-decision process

Research in Engineering Education has led to the development and dissemination of a number of different instructional strategies (such as active learning, problem based learning, and concept tests) contributing to greater student learning in the classroom. However, there is little research to demonstrate how Research Based Instructional Strategies (RBIS) are being propagated from the developers to engineering faculty for use in the classroom. To examine the process of dissemination, this study uses Rogers' Diffusion of Innovation framework, which has traditionally been used to examine the dissemination of technological innovations through a population or organization. Rogers discusses five stages (knowledge, persuasion, decision, implementation, and confirmation) of the innovation-decision process to explain how adopters make a decision about an innovation. To investigate faculty members' participation in the innovation-decision process, we conducted a survey of electrical, computer, and chemical engineering faculty (n = 221) teaching engineering sciences courses. The results show that ECE and ChE faculty members are located at a variety of stages throughout the innovation-decision process. However, most respondents have progressed past the knowledge phase; they are aware of the different RBIS. It is important to account for this when presenting an innovation or trying to encourage adoption of new practices, such as RBIS. It was found that workshops and presentations can influence the trial and use of RBIS when faculty are at the persuasion and decision stages. Also, women are more likely to try and use an RBIS than men. Many of the results found here are consistent with those found in a similar study done in physics education.
The relationship between gender role orientation and perceived self-competency in male and female adolescents

Relationships among gender, gender role orientation, grade, and perceived self-competency were examined in this study. Subjects were almost entirely Caucasian and included one hundred and ninety-four adolescents in the sixth through twelfth grades. The adolescents responded to the Children's Sex Role Inventory and the Self Perception Profile for Adolescents. Boys had higher perceived social and athletic competency; girls had higher perceived romantic appeal. Androgynous adolescents had the highest perceived scholastic competency, close friendship competency, and global self worth. Masculinity predicted perceived scholastic competency and close friendship competency in girls and boys and perceived global self worth in girls. Femininity predicted perceived scholastic competency in boys. There were no grade differences in perceived self-competency or in the relationship between gender, gender role orientation, and perceived self-competency.
Anisotropy studies on aligned HgBa2CaCu2O6+ delta powder: Confirmation of the collective-pinning theory for anisotropic materials.

Investigations on aligned $\mathrm{Hg}{\mathrm{Ba}}_{2}\mathrm{Ca}{\mathrm{Cu}}_{2}{\mathrm{O}}_{6+\ensuremath{\delta}}(\mathrm{Hg}\ensuremath{-}1212)$ powder were performed by measuring magnetization parallel and perpendicular to the applied magnetic field as a function of temperature, field, and the field orientation in the irreversible regime. The anisotropy ratio $\ensuremath{\varepsilon}\ensuremath{\approx}\frac{1}{5}$ is found indicating that Hg-1212 is one of the least anisotropic materials among the technically important high-${T}_{c}$ superconducting families. The scaling results for the magnetic field and the in-plane and the out-of-plane critical current densities agree precisely with the collective pinning theory and its scaling approach for anisotropic materials.
SELF ADAPTIVE FORECASTING RECONSIDERED

Recent work in demand forecasting has been done on a variation of exponential smoothing, which has been called a response surface. This response surface is analyzed, and an attempt is made to specify the nature of the sampling distributions involved. Then the response surface is compared to the basic single exponential smoothing forecast using actual demand data to see if it is a significantly better forecast.
The Career Structure in Biomedical Research: Implications for Training and Trainees The American Society for Cell Biology Survey on the State of the Profession

The scope of biomedical research in the United States has increased significantly over the last 20 years. At the same time that the number of trainees has proportionately increased, the number of traditional, tenured academic positions has declined.1 This appears to have profoundly changed the profession, at least in the view of the majority of established scientists who took their degrees before 1980. Today’s principal investigators may not be able to provide their trainees with the same clear sense of the future as did their own mentors for them. Throughout the community, there is anxiety and insecurity about the number and nature of the jobs today’s young scientists are likely to find. To address these issues, the American Society for Cell Biology (ASCB) determined to examine concerns raised by an increasing number of its members.2 The Society initiated a survey of its membership with the purpose of obtaining data that would reveal the extent of real and perceived opportunities in the profession of biomedical science, as well as the perceptions of those at different stages and representing different generations.3 The data set includes both raw data and statistical analysis, which reveals valid correlations for cohort and gender.4 A summary of the survey results was published as an editorial in Science (Marincola and Solomon, 1998 ). It is available in its entirety at www.ascb.org/ascb. The survey instrument was a printed four-page questionnaire, which was distributed in mid-1997 to a random 45% of the ASCB membership, including students, postdoctoral fellows, and “regular” (i.e., investigator) members in the United States. The questionnaire asked for information that was both objective, (e.g., date and institution of training and professional history) and subjective (e.g., satisfaction with one’s career and view of future prospects). The response rate was 65% (n = 2406). Twenty-five percent of the respondents are under age 40; 36% are between 40 and 49, and 28% are between 50 and 59. Twenty percent of respondents identify themselves as still in training, and these are nearly equally divided between men and women. In contrast, 36% of all respondents are women. Eighty-four percent of respondents identify themselves as white, and 9% identify themselves as Asian-American or Asian; very few respondents identify themselves as either Hispanic (2%) or black (1%). The Society acknowledged that by choosing its own membership as the study population, the results would be biased to reflect more favorable conditions than would a true cross-section of biomedical scientists and scientists-in-training. Membership in a scientific society by definition selects for those likely to attend the society’s meetings and to read and publish in its journals. Nonetheless, the ASCB leadership chose its own ranks for its accessibility and because it anticipated that if the survey results were cause for concern, that that concern would be if anything understated, not overstated, by the group selected.
Histories of Social Engagement and Adult Cognition: Midlife in the U.S. Study

Objectives. To evaluate whether social contacts, support, and social strain/conflict are related to executive function and memory abilities in middle-age and older adults. Methods. Longitudinal data on social contacts, support, and strain/conflict were examined in relation to executive function and memory at ages 35–85 years using data from the national Midlife in the U.S. (MIDUS) study. Age-related differences in patterns of association were also examined. Results. Regression analyses, controlling for age, sex, race, education, chronic health conditions, and health behaviors, revealed significant positive associations between histories of greater social contacts and support and both executive function and episodic memory, whereas declines in social contacts were negatively associated with both outcomes. Greater average reported frequency of social exchanges characterized by strain or conflict was negatively associated with executive function but not episodic memory. Patterns were generally consistent across different age groups; where differences were seen, associations were stronger in younger age group. Discussion. Positive and negative aspects of social relationships are related to cognition throughout adulthood, consistent with the hypothesis that social factors have life-long influences on cognition. Positive and negative aspects of so cial engagement may thus be important factors to consider in relation to efforts to promote optimal cognitive development and cognitive aging.
Docking Validation Resources: Protein Family and Ligand Flexibility Experiments

A database consisting of 780 ligand−receptor complexes, termed SB2010, has been derived from the Protein Databank to evaluate the accuracy of docking protocols for regenerating bound ligand conformations. The goal is to provide easily accessible community resources for development of improved procedures to aid virtual screening for ligands with a wide range of flexibilities. Three core experiments using the program DOCK, which employ rigid (RGD), fixed anchor (FAD), and flexible (FLX) protocols, were used to gauge performance by several different metrics: (1) global results, (2) ligand flexibility, (3) protein family, and (4) cross-docking. Global spectrum plots of successes and failures vs rmsd reveal well-defined inflection regions, which suggest the commonly used 2 A criteria is a reasonable choice for defining success. Across all 780 systems, success tracks with the relative difficulty of the calculations: RGD (82.3%) > FAD (78.1%) > FLX (63.8%). In general, failures due to scoring strongly outweigh t...
Nonlinear myocardial signal intensity correction improves quantification of contrast-enhanced first-pass MR perfusion in humans.

Purpose To study the nonlinearity of myocardial signal intensity and gadolinium contrast concentration during first-pass perfusion MRI, and to compare quantitative perfusion estimates using nonlinear myocardial signal intensity correction. Materials and Methods The nonlinearity of signal intensity and contrast concentration was simulated by magnetization modeling and evaluated in phantom measurements. A total of 10 healthy volunteers underwent rest and stress dual-bolus perfusion studies using an echo-planar imaging sequence at both short and long saturation-recovery delay times (TD70 and TD150). Perfusion estimates were compared before and after the correction. Results The phantom data showed a linear relationship (R2 = 1.00 and 0.99) of corrected signal intensity vs. contrast concentrations. Peak myocardial contrast concentration averaged 0.64 ± 0.10 mmol · L−1 at rest and 0.91 ± 0.21 mmol · L−1 during stress for TD70 and were similar for TD150 (P = not significant [NS]). The corrections were larger for stress than rest perfusion and larger for TD150 than TD70 studies (both P < 0.01). Perfusion estimates of TD70 and TD150 stress studies were significantly different before the correction (P < 0.01) but equivalent after the correction (P = NS). Conclusion The nonlinearity between signal intensity and myocardial contrast concentration in perfusion MRI can be corrected through magnetization modeling. A nonlinear correction of myocardial signal intensity is feasible and improves quantitative perfusion analysis. J. Magn. Reson. Imaging 2008. © 2008 Wiley-Liss, Inc.
Determination of site amplification in the Los Angeles urban area from inversion of strong-motion records

Abstract The amplification of strong ground motion at sites in the greater Los Angeles, California, region is determined using the generalized-inverse method of Andrews (1986). Site-amplification estimates are determined at 281 strong-motion sites that provided horizontal-component accelerograms from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, or 1994 Northridge mainshocks. The estimates are determined relative to the spectral level recorded at a single reference site. In a second inversion, a source-site interaction term is added to Andrews9s (1986) model to quantify the effect selected mainshock records have on site-amplification estimates. The source-site interaction term is applied to the San Fernando Valley sites9 records of the Northridge earthquake and to three Los Angeles basin sites9 records of the Whittier Narrows mainshock. Site-amplification spectra are averaged within two frequency bands: the intermediate-frequency band (IFB) from 0.5 to 1.5 Hz and the high-frequency band (HFB) from 2 to 6 Hz. Results are displayed on maps of surficial geology. Average spectral levels are correlated with average shear-wave velocity in the uppermost 30 m, a geotechnical parameter used by the National Earthquake Hazards Reduction Program (NEHRP) to characterize site amplification. Statistically significant correlation is found in both frequency bands. Average spectral amplification levels for NEHRP class B, C, and D sites in the LA urban area are determined. These averages display an expected increase in spectral amplification with category, with a more pronounced variation in the IFB than in the HFB. Considerable overlap in the one-standard-deviation range of the C and D site levels is found in both IFB and HFB, suggesting that site-specific spectral amplification is influenced by more than just near-surface shear-wave velocity. Average site-amplification levels are compared with those obtained from Northridge aftershock records at 28 collocated sites and are found to be in reasonably good agreement in both frequency bands. Some interesting outliers, that is, sites for which the mainshock- and aftershock-determined amplifications differ significantly, are identified as sites that experienced ground failure during the Northridge mainshock.
Nitric oxide-induced changes in intracellular zinc homeostasis are mediated by metallothionein/thionein

We hypothesized that metallothionein (MT), a cysteine-rich protein with a strong affinity for Zn2+, plays a role in nitric oxide (NO) signaling events via sequestration or release of Zn2+ by the un...
"Physicians to a Dying Planet": Helen Caldicott, Randall Forsberg, and the Anti-Nuclear Weapons Movement of the Early 1980s

Abstract This article profiles two important leaders of the anti-nuclear weapons movement in the United States during the early 1980s. Helen Caldicott and Randall Forsberg were visionary, transformational leaders who crossed a variety of boundaries for the common good, and as such are prime exemplars of integrative leadership in action. Caldicott was a charismatic figure who used her status as physician and mother to rally a worldwide movement opposed to the ongoing proliferation of nuclear weapons and talk of “winnable” nuclear war. Forsberg was the main architect of the nuclear “Freeze” campaign whose humanitarian vision and common-sense approach to political action helped unite diverse segments of the American public around the Freeze proposal and push the Reagan administration towards disarmament talks with the Soviet Union. The article analyzes the leadership of both women in historical and social–scientific context, shedding light on two relatively unknown — yet important — social movement leaders whose stories have much to tell us about integrative public leadership, the challenges faced by women leaders, and the strengths and pitfalls of charismatic leadership.
Perceptions of informal care givers: health and support services provided to people with multiple sclerosis.

Purpose. About 30% of people with multiple sclerosis (MS) need some form of home care assistance, with 80% of that assistance provided by informal or unpaid care givers. This study focuses on the care givers to 530 more disabled people with MS, with the objective to learn more about informal care giving to people with greater dependency and need for assistance.Method. The data presented in this study were collected in a national survey of 530 informal care givers to people with MS who have greater levels of physical dependency.Results. About 70% of informal care givers responded that assisting the person with MS perform daily activities or personal care took up the largest amount of their care giving time. Care givers also reported a range of home and community-based services that would make care giving easier or improve the care provided. However, informal care givers generally reported low satisfaction with health insurance coverage of these services, especially coverage by health maintenance organizati...
Response of human DNA polymerase ι to DNA lesions

Lesion bypass is an important mechanism to overcome replication blockage by DNA damage. Translesion synthesis requires a DNA polymerase (Pol). Human Pol iota encoded by the RAD30B gene is a recently identified DNA polymerase that shares sequence similarity to Pol eta. To investigate whether human Pol iota plays a role in lesion bypass we examined the response of this polymerase to several types of DNA damage in vitro. Surprisingly, 8-oxoguanine significantly blocked human Pol iota. Nevertheless, translesion DNA synthesis opposite 8-oxoguanine was observed with increasing concentrations of purified human Pol iota, resulting in predominant C and less frequent A incorporation opposite the lesion. Opposite a template abasic site human Pol iota efficiently incorporated a G, less frequently a T and even less frequently an A. Opposite an AAF-adducted guanine, human Pol iota was able to incorporate predominantly a C. In both cases, however, further DNA synthesis was not observed. Purified human Pol iota responded to a template TT (6-4) photoproduct by inserting predominantly an A opposite the 3' T of the lesion before aborting DNA synthesis. In contrast, human Pol iota was largely unresponsive to a template TT cis-syn cyclobutane dimer. These results suggest a role for human Pol iota in DNA lesion bypass.
Widmanstaetten patterns in josephinite, a metal-bearing terrestrial rock.

Widmanstaetten patterns have been found in several specimens of josephinite, a complex, metamorphosed, metal-bearing rock from placers on serpentinized peridotite in southwest Oregon. The patterns, in interior less-altered regions of the specimens, are typical of exsolution textures produced during slow cooling of a homogeneous metal. The bulk composition of the metal phases indicates that the homogeneous metal must have existed at temperatures above 500°C. Josephinite Widmanstaetten patterns are the first known in terrestrial rock. We interpret them as further evidence that josephinite was derived from the mantle.
Herbicide metabolism in plants—I

Abstract A “soluble” enzyme system from soybean, which catalyzes the biosynthesis of N -glucosylarylamines, has been purified 20-fold by differential centrifugation, ammonium sulfate fractionation, gel filtration, and cellulose ion exchange chromatography. The enzyme was specific for the nucleotide glucosyl donors uridinediphosphate glucose (UDPG) and thymidinediphosphate glucose (TDPG), but exhibited a broad specificity toward acceptor arylamines. A number of substituted anilines and aminobenzoic acids were studied as acceptor arylamines including 2,5-dichloro-3-aminobenzoic acid (amiben) and 3,4-dichloroaniline, a metabolite of 3,4-dichloropropionanilide (propanil) in higher plants. The partially purified enzyme was found to have an optimum pH of 7·5 with 3,4-dichloroaniline as the arylamine acceptor and was inhibited by sulfhydryl reagents. The Km constants for UDPG and 3,4-dichloroaniline were 1·88 × 10 −3 M and 5·63 × 10 −4 M respectively. The Ki constant for uridinediphosphate (UDP) was 4·84 × 10 −4 M.
Disseminating a successful dietary intervention to faith communities: feasibility of using staff contact and encouragement to increase uptake.

Abstract Objective To test the feasibility of a dissemination strategy to increase faith communities' (FCs) adoption and implementation of a tested dietary intervention. Design The study was a randomized, controlled trial that took place over a 9-month period. Setting Seattle, Washington, metropolitan area. Participants Seven FCs assigned to an intervention group and five to a comparison group. Intervention All FCs received intervention materials, monetary support, and a Healthy Eating Coordinator (HEC), who was available to answer questions or provide assistance. Intervention FCs additionally received monthly contact from the HEC. Main Outcome Measure The main outcome measure was the number of intervention activities the FCs reported over the intervention period. Analysis The authors performed descriptive analyses and compared median number of activities performed by intervention and control FCs with Wilcoxon rank-sum tests. Results Intervention FCs implemented a median of 3 intervention activities, whereas control FCs implemented a median of 0 intervention activities ( P = .05). Conclusions and Implications These findings indicate that regular contact from HECs is a feasible dissemination strategy for FCs. Further research is needed to determine how to improve the effectiveness of this contact.
Multithreaded agent-based simulation

Multithreading can significantly increase the performance of large agent-based simulations on multicore systems, but agent-based software packages do not commonly offer adequate support for multithreading. This report describes alterations and additions made to the MASON agent-based simulation package that allow the application programmer to make use of multiple threads easily and without radical change to conventional agent-based programming style. The report confirms performance gains with the results of test runs.
Classification of Glottic Insufficiency and Tension Asymmetry Using a Multilayer Perceptron

Objective: Laryngeal function can be evaluated from multiple perspectives, including aerodynamic input, acoustic output, and mucosal wave vibratory characteristics. To determine the classifying power of each of these, we used a multilayer perceptron artificial neural network (ANN) to classify data as normal, glottic insufficiency, or tension asymmetry. Study design: Case series analyzing data obtained from excised larynges simulating different conditions. Methods: Aerodynamic, acoustic, and videokymographic data were collected from excised canine larynges simulating normal, glottic insufficiency, and tension asymmetry. Classification of samples was performed using a multilayer perceptron ANN. Results: A classification accuracy of 84% was achieved when including all parameters. Classification accuracy dropped below 75% when using only aerodynamic or acoustic parameters and below 65% when using only videokymographic parameters. Conclusions: Samples were classified with the greatest accuracy when using a wide range of parameters. Decreased classification accuracies for individual groups of parameters demonstrate the importance of a comprehensive voice assessment when evaluating dysphonia. Laryngoscope, 2012
Fully Discrete Analysis of a Discontinuous Finite Element Method for the Keller-Segel Chemotaxis Model

This paper formulates and analyzes fully discrete schemes for the two-dimensional Keller-Segel chemotaxis model. The spatial discretization of the model is based on the discontinuous Galerkin methods and the temporal discretization is based either on Forward Euler or the second order explicit total variation diminishing (TVD) Runge-Kutta methods. We consider Cartesian grids and prove fully discrete error estimates for the proposed methods. Our proof is valid for pre-blow-up times since we assume boundedness of the exact solution.