cssi/SciSciGPT-SciSciNet huggingface dataset:
Examining the factorial validity of the Quality of Life Scale.

Quality of life (QoL) is important to assess in patient care. Researchers have previously claimed validity of the Quality of Life Scale (QOLS) across multiple samples of individuals, but close inspection of results suggest further psychometric investigation of the instrument is warranted. Therefore, the purposes of this study were to: 1) evaluate the proposed five-factor, 15-item and three-factor, 16-item QOLS; 2) if the factor structure could not be confirmed, re-assess the QOLS using exploratory factor analysis (EFA) and covariance modeling to identify a parsimonious refinement of the QOLS structure for future investigation. Participants varying in age, physical activity level, and identified medical condition(s) were recruited from clinical sites and ResearchMatch. Confirmatory factor analyses (CFA) were performed on the full sample (n = 1036) based on proposed 15- and 16-item QOLS versions. Subsequent EFA and covariance modeling was performed on a random subset of the data (n1 = 518) to identify a more parsimonious version of the QOLS. The psychometric properties of the newly proposed model were confirmed in the remaining half of participants (n2 = 518). Further examination of the scale psychometric properties was completed using invariance testing procedures across sex and health status sub-categories. Neither the 15- nor 16-item QOLS CFA met model fit recommendations. Subsequent EFA and covariance modeling analyses revealed a one-factor, five-item scale that satisfied contemporary statistical and model fit standards. Follow-up CFA confirmed the revised model structure; however, invariance testing requirements across sex and injury status subgroups were not met. Neither the 15- nor 16-item QOLS exhibited psychometric attributes that support construct validity. Our analyses indicate a new, short-form model, might offer a more appropriate and parsimonious scale from some of the original QOLS items; however, invariance testing across sex and injury status suggested the psychometric properties still vary between sub-groups. Given the scale design concerns and the results of this study, developing a new instrument, or identifying a different, better validated instrument to assess QoL in research and practice is recommended.
Natural History and Progression of Craniofacial Fibrous Dysplasia: A Retrospective Evaluation of 114 Patients From Massachusetts General Hospital.

Purpose The natural history of fibrous dysplasia (FD) is poorly understood. The purpose of this study was to identify differences in demographic, clinical, and radiographic characteristics among patients with craniofacial FD, including McCune-Albright syndrome (MAS), polyostotic fibrous dysplasia (PFD), and monostotic fibrous dysplasia (MFD). We hypothesized that patients with MAS would show higher disease severity, have more complications, and undergo more operations than those with PFD or MFD. Patients and Methods A retrospective cohort study of patients with MAS or FD, evaluated at Massachusetts General Hospital from 2000 to 2018, was implemented. Patients of all ages and genders were identified through Massachusetts General Hospital Data Registries using International Classification of Diseases, Ninth Revision (ICD-9) and International Classification of Diseases, Tenth Revision (ICD-10) codes. Those with adequate clinical and radiographic data were included. Predictor variables were diagnosis of MAS, PFD, or MFD; age; and gender. Outcome variables included severity of disease at initial presentation (aggressive, nonaggressive and slow growing, or quiescent), number of operations, and complications: pain, sensory disturbances, pathologic fracture, airway obstruction, osteomyelitis, and dental findings. Data were analyzed with descriptive statistics and assessed for significance using χ2 tests and analysis of variance (P Results A total of 229 patients were identified: 114 had craniofacial FD, and 70 of these 114 (61.4%) met the inclusion criteria (48 of whom were female patients). The average age at diagnosis was 23.5 years; mean length of follow-up, 5.8 years. Diagnoses included MAS in 9 patients, PFD in 24, and MFD in 37. Signs and symptoms at initial presentation were pain (n = 29), sensory abnormalities (n = 13), facial deformity or swelling (n = 54), and dental findings (n = 25). At presentation, the biological behavior of disease was 77.8% aggressive, 11.1% nonaggressive, and 11.1% quiescent in the MAS group; 41.7%, 41.7%, and 16.7%, respectively, in the PFD group; and 29.7%, 29.7%, and 40.5%, respectively, in the MFD group. Patients with MAS were younger and were more likely to have pain, pathologic fractures, more bones involved, bilateral disease, and visual symptoms than those with PFD or MFD. MAS patients underwent more operations (mean, 4.2 ± 4.18) than those with PFD (mean, 2.6 ± 2.31; P = not significant) or MFD (mean, 1.7 ± 1.28; P = .010). Conclusions The results of this study indicate that patients with MAS, presumably with the same mutation, are more likely to have aggressive disease, complications, and more operations than those with PFD or MFD.
The Politics of Foreign Aid: A Median Voter Perspective

The paper presents a model where the median voter in the donor country determines the support of foreign aid. It is first established that an individual in the donor country is affected by the direct benefits (due to altruism) and costs (due to taxes) of giving aid, and by the indirect benefits or costs of a change in the terms of trade. Then it is shown that the latter effect works through changing both the donor country's average income and its distribution of income. Given the stylized facts of a capital-abundant donor country and relatively capital-poor median voter, it is shown how redistribution-of-income effects soften the impact of terms-of-trade changes on the political support for foreign aid.
Historical Perspective of Clinical Nano and Microparticle Formulations for Delivery of Therapeutics

Nano and micro-technologies are used for therapeutic delivery of biologics and small molecules in formulations ranging in size from one nanometer to 100 microns or more. Here we review the unique physiochemical properties of these technologies and how they lead to more beneficial drug pharmacokinetics and toxicity over conventional formulations.
In-Situ TEM Analysis of the Phase Transformation Mechanism of a Cu-Al-Ni Shape Memory Alloy Fabricated with Different Quenching Speeds

A shape memory alloy (SMA) recovers its original shape after deformation through martensitic phase transformation (PT), which is diffusionless and involves shear deformation. Minimizing PT hysteresis is of crucial importance for reliability of SMA-based devices, where the stress caused by thermal hysteresis leads to functional degradation. As a result, understanding structural factors that control PT, including phase nucleation and growth, is critical for development of materials with high reversibility. In this study, the PT mechanism (from γ1' martensite to β1 austenite phase) in Cu-Al-Ni SMAs was investigated by preparing alloy with different quenching rates, resulting in very different transition temperatures. By characterizing the atomic scale composition and microstructure we show that slow quenching induces nanoprecipitation that change chemistry and strain field of the matrix alloy, while fast quenching avoids the formation of these nanoprecipitates. In-situ monitoring of the PT process in TEM demonstrate a growth-dominant conventional PT mechanism with low hysteresis in the fast quench sample. On the other hand, the alloy with precipitates shows a nucleation-dominant PT mechanism with suppression of phase growth that induces high thermal hysteresis. Our finding provides valuable insights into the fabrication of SMAs with better reliability.
Adaptive Hybrid Control for Low Resolution Feedback Systems with Application on a Novel Microinjector: Ros-drill

A novel hybrid control logic is deployed on a novel cellular microinjector called the Ros-Drill (Rotationally Oscillating Drill). Ros-Drill technology is primarily developed for ICSI (Intra Cytoplasmic Sperm Injection). The new structure offers an inexpensive tool which performs precise micro motion control on an actuator (DC motor), creating high-frequency rotational oscillations at the tip of an injecting pipette, which, in turn, drills the cells. Angular motion control presents no particular difficulties when the application uses high fidelity measurements of the motion being controlled. However, size, costs and accessibility of the needed technology relevant to the hardware components negatively influence the design of the control settings. In this presentation we describe an adaptive-hybrid control structure which is developed around a commonly available microcontroller core. We consider three limiting factors: bounded sampling speed of the controller, and extremely low relative resolution of position measuring sensor, as well as the limited capabilities of generating the desired rotational trajectory. We present a novel methodology to overcome these specific problems utilizing an adaptive, robust and optimal PID (proportional-integral and derivative) control strategy. It is demonstrated that the required fine rotational motion for the cellular injections is obtained with desirable fidelity, despite the stated shortfalls in the components. Field experiments and preliminary biological test results will also be included in the discussions.
Fossil Crabs From Tepee Buttes, Submarine Seeps of the Late Cretaceous Pierre Shale, South Dakota and Colorado, U.s.a.

Tepee Buttes are low conical hills which occur in scattered clusters along the strike of the Late Cretaceous Pierre Shale near Pueblo, Colorado, and around the Black Hills of South Dakota, Montana, and Wyoming. These erosional landforms develop around resistant columnar limestone masses thought to have been deposited by warm, methane-rich, submarine springs within relatively homogeneous, less resistant claystones. Origin of the Tepee Buttes is attributed to dewatering of underlying claystones. The submarine springs provided a unique habitat on the Western Interior Cretaceous sea bottom for growth of large populations of the lucinid bivalve, Nymphalucina occidentalis, often preserved in living position in reef-like masses encircling the spring vents. Concentration of abundant biomass immediately around the spring vents formed the basis of communities preserved as the Nymphalucina Assemblage dominated by N. occidentalis, but including ammonoid cephalopods, other bivalved mollusks, gastropods, foraminiferans, and a few decapod crustaceans. Fragments of grounded fossilized gymnosperm and angiosperm wood riddled with Teredo borings are also found on the vent cores. Twenty specimens of decapod crustaceans representing three new species of crabs were collected from Tepee Buttes near Oelrichs and Newell, South Dakota, and collecting near Pueblo, Colorado, yielded specimens belonging to three new species, as well as one specimen of Hoplitocarcinus punctatus. The new taxa include Heus foersteri, new genus and species, Raninella manningi, new species (family Raninidae), and Plagiophthalmus bjorki, new species (family Prosopidae ). Descriptions, illustrations, and comparisons of new taxa with previously described members of the family are given.
Longitudinal multifrequency rhythm structure of self-measured blood pressure gauges aging over two decades

The study of a clinically healthy man, 20.5 years of age at start of study, who self-measured systolic (S) and diastolic (D) blood pressure (BP) several times daily for >340 days/year for 21 years is presented. Notwithstanding the lack of data during sleep, a circadian rhythm is demonstrated (P >
Fluorometric Determination of Deoxyribonucleic Acid in Bacteria with Ethidium Bromide

A simple, sensitive, and rapid method is presented for the determination of deoxyribonucleic acid (DNA) in both gram-positive and gram-negative bacteria. It is based upon the fluorometric determination of DNA with ethidium bromide after alkaline digestion of the bacteria to hydrolyze the interfering ribonucleic acid. The assay takes less than 2 hr. Its sensitivity is at least 0.2 mug of DNA in a final solution of 4 ml and it uses commonly available filter or double monochromator fluorometers. Judicious choice of light source and filters allows an additional 10-fold increase in sensitivity with a filter fluorometer. Turbidity caused by bacteria or insoluble polysaccharides does not interfere with the fluorescence measurements. There was no significant difference between the results obtained with this method and those obtained with the indole and diphenylamine methods when these assays were applied to Escherichia coli and sucrose- or glucose-grown Streptococcus mutans. The method was also tested by determining the specific growth rate of E. coli. This new procedure should be especially useful for the determination of bacterial DNA in dilute suspensions and for the estimation of bacterial growth or DNA replication where more conventional methods are not applicable or sensitive enough.
Studies of the formation of uranyl(VI) from uranium dioxide and chlorine in molten alkali chlorides: E.m.f. measurements and thermodynamic values

Abstract E.m.f. measurements were used to calculate thermodynamic properties of the reaction of uranium dioxide with chlorine forming uranyl chloride in several molten salt solutions. The thermodynamic data are given for this reaction in eutectic NaClLiCl, eutectic KClLiCl, 1:1 KClLiCl, and 1:1 KClNaCl; and e.m.f. data are given for the reaction in NaClLiCl, KClLiCl, and KClNaCl solvent systems of systematically varied composition. The variations of these data with solvent composition show an increasing stability of UO 2 (VI) with the decreasing effective charge density of the solvent cations. This is attributed to an increasing efficacy, or activity, of the chloride resulting from the decreasing polarizing power of the solvent cations.
Iron availability limits the ocean nitrogen inventory stabilizing feedbacks between marine denitrification and nitrogen fixation

Recent upward revisions in key sink/source terms for fixed nitrogen (N) in the oceans imply a short residence time and strong negative feedbacks involving denitrification and N fixation to prevent large swings in the ocean N inventory over timescales of a few centuries. We tested the strength of these feedbacks in a global biogeochemical elemental cycling (BEC) ocean model that includes water column denitrification and an explicit N fixing phytoplankton group. In the northern Indian Ocean and over longer timescales in the tropical Atlantic, we find strong stabilizing feedbacks that minimize changes in marine N inventory over timescales of ∼30–200 years. In these regions high atmospheric dust/iron inputs lead to phosphorus limitation of diazotrophs, and thus a tight link between N fixation and surface water N/P ratios. Maintenance of the oxygen minimum zones in these basins depends on N fixation driven export. The stabilizing feedbacks in other regions are significant but weaker owing to iron limitation of the diazotrophs. Thus Fe limitation appears to restrict the ability of N fixation to compensate for changes in denitrification in the current climate, perhaps leading the oceans to lose fixed N. We suggest that iron is the ultimate limiting nutrient leading to nitrogen being the proximate limiting nutrient over wide regions today. Iron stress was at least partially alleviated during more dusty, glacial times, leading to a higher marine N inventory, increased export production, and perhaps widespread phosphorus limitation of the phytoplankton community. The increased efficiency of the biological pump would have contributed to the glacial drawdown in atmospheric CO2.
Time-stretched analog-to-digital conversion (TSADC)

Summary form only given. The ability to perform ultrafast A/D and D/A conversion is critical for high performance communication and radar systems. Challenges with traditional approaches have led us to propose the concept of time-stretch preprocessing as a possible solution to the ultrafast A/D conversion. In Nyquist type A/D converters (ADCs) time stretching increases the effective input bandwidth and sampling rate of the ADC. In /spl Sigma/-/spl Delta/ type converters, it has the additional benefit of reducing the quantization noise within the signal bandwidth. In this paper, we will present the experimental data and theoretical analysis for time-manipulation of electrical signal using optoelectronic techniques. We also introduce a new discrete-time rendition of this technique with near transform-limited temporal resolution. Analytical and numerical calculation of the fundamental limits of this approach will be presented. We will conclude by presenting an overview of the COAST (Consortium for Optical A/D System Technology), a new DARPA funded UCLA-lead consortium consisting of 8 Universities, industry and national laboratories dedicated to research in optically assisted A/D conversion.
THz phonon-polariton spectroscopic imaging

A family of methods has been developed recently for generation, control, and visualization of terahertz (THz) phonon-polaritons in polar crystals 1 . Phonon-Polaritons (below simply "polaritons") are admixture of polar lattice vibration and electromagnetic modes of similar frequency and wave vector. In this paper, we discuss the possible application of phonon-polariton spectroscopic imaging to the chemical sensing. Advantages of the polariton imaging for the use of sensor application include (1) No need for THz optics, (2) Compactness of the cell, and (3) Quick acquisition of time domain signal. In this paper, we present experimental results of solid and liquid samples, and show simultaneous measurement of multiple samples.
Gender, Race, and Politics in the Midwest: Black Club Women in Illinois

During the thirty year period from 1890 to 1920, the African American club women in Illinois helped establish the largest national network of black club women in the country, The National Association of Colored Women, created hundreds of female associations, organized the only federation of its kind in the state, The Illinois Federation of Colored Women, and cast ballots for the first black elected to the city council. Hendricks focuses on the Progressive Era, a period of numerous and unusual challenges not replicated in other regions of the country. Illinois and several of the other Midwestern states were affected by the burgeoning industrial economy and by the massive immigration of African American seeking economic opportunity.Chicago, by 1920, housed one of the largest and most urbanized black communities in the country. While few legal social and political restrictions were imposed on blacks, the state was the site of some of the worst race riots in the nation during the first two decades of the twentieth century. Club women successfully met these challenges by becoming social and political agents of reform and community uplift. Through their own volunteer ism and fund raising they combated the problems of homelessness, unemployment, illiteracy, high mortality, and inadequate health care that plagued African Americans.They opened kindergartens, day nurseries, orphanages, settlement houses, elderly homes, recreation centers, and medical care facilities. They also demonstrated their political prowess by developing a gendered political culture. They formed suffrage clubs, entered public debates on major issues and voiced their opinions on the importance of holding politicians accountable for their actions. The Illinois club women also played a primary role in the election of Oscar Stanton DePriest as the first black alderman in Chicago. Blacks in the Diaspora.
Do Late Adolescent Fathers Have More Depressive Symptoms than Older Fathers

Although fathers are increasingly a focus of attention in research, there is a dearth of research on depressive symptoms among fathers, especially young fathers with toddlers. This study used longitudinal data to examine what risk factors, including the age status of fathers (e.g., late adolescence, emerging adulthood, and adulthood), may be associated with depressive symptoms of fathers when their children were 3 and 5 years of age. A subsample of families for which complete data were available on all variables was used in the analyses (n = 1,403). About 46% of study sample was African American, 27% White, 23% Hispanic, and 4% other race/ethnicity. Paternal depressive symptoms were measured using Composite International Diagnostic Interview-Short Form (CIDI-SF). Late adolescent fatherhood was significantly associated with third-year paternal depressive symptoms but not with fifth-year depressive symptoms. Those who reported low social support were more likely to be depressed at both times. Fathers who did not work for regular pay were more likely to be depressed at the third-year follow-up, but not at the fifth-year follow-up. Parenting stress and being booked/charged with a crime were not associated with third-year paternal depressive symptoms, but were with fifth-year paternal depressive symptoms. This study emphasizes the importance of screening for depressive symptoms of fathers even before the birth of their child and monitoring and treating postpartum depressive symptoms, as first-year depressive symptoms was a significant predictor for third- and fifth-year depressive symptoms. Service providers should focus on the mental health of fathers as well as mothers to promote healthy environments for their children.
The Impact of Cost Displays on Ordering

The Authors’ Reply—We share Dr. Galen’s concern that cost displays should be thoughtfully implemented in a clinical setting. To that end, the cost displays in our study did not require providers to act on the information displayed. The passive nature of the displays allowed physicians to maintain autonomy over clinical decision-making. Additionally, we used the Medicare reimbursement rate as a proxy for relative costs of tests, rather than as the true charge to the payer. We agree that future studies should focus on whether cost displays impact clinical outcomes. However, we must also work to reduce routine ordering of large panels of laboratory tests in primary care. The downstream costs of working up false positive tests are substantial and wasteful. Future research should explore the impact of displays that show the relative clinical value of tests and incorporate key clinical guidelines and benchmarks. We must continue to evaluate ways to inform providers about the value of the care they deliver.
Novel waveform and processing techniques for monostatic and bistatic radar

In this paper, we study the resolution properties of linear FM pulses (chirps). Based on the ambiguity surface properties of chirp pulses, we propose a transmission strategy and a processing algorithm that has better delay-Doppler resolution than traditional matched filtering. It is shown that the improvement in resolution is accompanied by a small degradation in detection performance. We also discuss the general requirements on the signal set that will result in improved resolution properties when using the proposed form of processing. Our results also show that we can change resolution performance for detection performance under certain conditions. The contribution of our proposed scheme is a significant increase in delay-Doppler resolution without a significant increase in system or computational complexity or a significant degradation in detection performance. We also extend the results to a simple bistatic radar configuration and evaluate the performance for orthogonal and near-orthogonal transmitted signals under varying conditions.
Axial field engineering in the nonparaxial domain

The design of axially super-resolving phase pupil filters based on the scalar theory of diffraction is limited to low numerical aperture (NA ) focusing. To account for the non-paraxiality encountered in high-NA optical systems, we propose a design procedure based on the method of generalized projections that incorporates the electromagnetic theory of diffraction. A solution is identified that narrows the axial intensity of the central lobe by 29% while maintaining the side lobe intensity below 52% of the peak intensity. It is found that solutions obtained with this method depend strongly on the applied constraints and the starting pupil filter.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A geodesic-active-contour-based variational model for short-axis cardiac MR image segmentation

We propose a novel geodesic-active-contour-based GAC-based variational model that uses two level-set functions to segment the right and left ventricles and the epicardium in short-axis magnetic resonance MR images. For the right ventricle, the myocardial wall is typically very thin and hard to identify using the resolution of existing MR scanners. We propose to use two level sets to identify both the endocardial wall by pushing away one level-set function from another, in the setting of the edge-driven GAC model with a new edge detection function. Existing edge detection functions have strict restrictions on the location of initial contours. We develop a new edge detection function that relaxes this restriction and propose an iterative method that uses a sequence of edge detection functions to minimize the energy of our model successively. Experimental results are presented to validate the effectiveness of the proposed model.
Powdered gold as a veneer over silver amalgam restorations: a preliminary report.

Abstract This preliminary report suggests the possibility of using powdered gold over freshly condensed silver amalgam in Class I, II, and large Class V cavities. If the amalgam is prepared according to the Eames technique and if the gold is condensed over the amalgam within 10 minutes after preparation of the amalgam, the gold should attach itself to the amalgam. The cause of the bond between the gold and the amalgam is under investigation. This technique is not feasible and is not advocated at this time. However, further study of it is warranted.
Take the expressway to go greener

Society is going green! Increasingly, people are committing to choose equipment with lower energy demands. Historically, the growth of green has been repeatedly motivated by various economic upheavals, such as the 1973 oil crisis. More recently, the Lehman Brothers crisis in 2008 inspired green initiatives in various industry sectors: surges in solar-power generation, eco-friend-ly white-goods products, consumer electronics, and green cars.
Vascular endothelial growth factor, FLT-1, and FLK-1 analysis in a pancreatic cancer tissue microarray.

BACKGROUND Measures of vascular endothelial growth factor (VEGF) expression in pancreatic cancer typically have been qualitative or semiquantitative. The objective of this study was to use a series of algorithms called AQUA that quantitatively assesses protein expression on tissue microarrays (TMAs) to compare in situ expression of VEGF and its primary receptors, VEGF receptor 1 (FLT-1) and VEGF receptor 1 (FLK-1), on a pancreatic cancer TMA. METHODS TMAs were constructed by arraying 1.5-mm cores from 76 samples of pancreatic adenocarcinoma (1996-2002) that were obtained from the archives of the Yale Department of Pathology. The staining for AQUA was similar to standard immunohistochemistry and involved antigen retrieval and the application of primary antibodies, but with epifluorescence detection. Slides were counterstained with 4′,6-diamidino-2-phenylindole for nuclear visualization and cytokeratin for membrane visualization. The primary antibodies used were VEGF, FLT-1, FLK-1, and cytokeratin. RESULTS Disease stage was highly prognostic for outcome, as expected. Total amounts of VEGF and its receptors were assessed within the tumor mask and were divided into quartiles. Kaplan–Meier survival curves showed that VEGF and FLK-1 were not associated clearly with outcome. However, the expression of FLT-1 was correlated significantly, and the patients who had tumors with the lowest expression FLT-1 levels had the worst survival (P = .0038). In multivariate analysis, FLT-1 expression was an independent prognostic factor for overall survival (P = .0044). CONCLUSIONS VEGF and its 2 principal receptors were expressed to varying degrees in tumors of the pancreas. A significant association was found between low expression of FLT-1 and both poor prognosis and advanced stage, suggesting that tumor expression of this VEGF receptor is a marker of less aggressive disease. Cancer 2006. © 2006 American Cancer Society.
PDF methods for turbulent reactive flows

Abstract The aim of the methods described is to calculate the properties of turbulent reactive flow fields. At each point in the flow field, a complete statistical description of the state of the fluid is provided by the velocity-composition joint pdf. This is the joint probability density function (pdf) of the three components of velocity and of the composition variables (species mass fractions and enthalpy). The principal method described is to solve a modelled transport equation for the velocity-composition joint pdf. For a variable-density flow with arbitrarily complex and nonlinear reactions, it is remarkable that in this equation the effects of convection, reaction, body forces and the mean pressure gradient appear exactly and so do not have to be modelled. Even though the joint pdf is a function of many independent variables, its transport equation can be solved by a Monte Carlo method for the inhomogeneous flows of practical interest. A second method that is described briefly is to solve a modelled transport equation for the composition joint pdf. The objective of the paper is to provide a comprehensive and understandable of the theoretical foundations of the pdf approach.
Evaluation of a Portable Clinical Blood Analyzer in the Emergency Department

Objective: To assess the potential effects of rapid bedside blood analysis on patient management in the ED. Methods: A prospective, nonrandomized clinical study was conducted over a consecutive ten-month period (August 1992 to May 1993). Blood samples drawn from a convenience sample of 960 patients for analysis of Na +, K +, Cl-, BUN, glucose, and/or hematocrit (Hct) were simultaneously analyzed by portable clinical analyzer (PCA) and by routine methods in the central laboratory. Caregivers were blinded to the PCA values; patient care was based solely on central laboratory results. Physicians were surveyed after the completion of patient care. Results: The PCA results were available 31 minutes (mean) sooner than were the central laboratory results for Hct, 43 minutes faster for Na +, K+, and Cl-, and 44 minutes faster for BUN and glucose. Except for Hct and glucose, the values obtained from the PCA were not significantly different from the central clinical blood analyzer laboratory values. When surveyed, the physicians caring for the patients reported that had the PCA results been available, a different or an earlier therapeutic approach would have resulted in 9.5% of the cases. The decision to release or admit the patient was based on one or more of the laboratory values for 10.7% of patients sampled. In no case in this series did a physician report that final ED clinical outcome would have been affected. Conclusions: In our ED, the PCA yielded faster reporting of laboratory values. These earlier results might have reduced the length of stay in the ED for 17.3% of patients studied. Selective use of a handheld portable analyzer might decrease time to therapeutic interventions and time to disposition.
Optimal determination of user-oriented clusters

User-oriented clustering schemes enable the classification of documents based upon the user perception of the similarity between documents, rather than on some similarity function presumed by the designer to represent the user criteria. In this paper, an enhancement of such a clustering scheme is presented. This is accomplished by the formulation of the user-oriented clustering as a function-optimization problem. The problem formulated is termed the Boundary Selection Problem (BSP). Heuristic approaches to solve the BSP are proposed and a preliminary for evaluation of these approaches is provided.
Location, Location, Location: Compartmentalization of Early Events in Leukotriene Biosynthesis

Leukotrienes (LTs), derived from arachidonic acid (AA) released from the membrane by the action of phospholipase A2, are potent lipid mediators of the inflammatory response. In 1983, Dahlen et al. demonstrated that LTC4, LTD4, and LTE4 mediate antigen-induced constriction of bronchi in tissue obtained from subjects with asthma (Dahlen, S. E., Hansson, G., Hedqvist, P., Bjorck, T., Granstrom, E., and Dahlen, B. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 1712–1716). Over the last 25+ years, substantial progress has been made in understanding how LTs exert their effects, and a broader appreciation for the numerous biological processes they mediate has emerged. LT biosynthesis is initiated by the action of 5-lipoxygenase (5-LOX), which catalyzes the transformation of AA to LTA4 in a two-step reaction. Ca2+ targets 5-LOX to the nuclear membrane, where it co-localizes with the 5-LOX-activating protein FLAP and, when present, the downstream enzyme LTC4 synthase, both transmembrane proteins. Crystal structures of the AA-metabolizing LOXs, LTC4 synthase, and FLAP combined with biochemical data provide a framework for understanding how subcellular organizations optimize the biosynthesis of these labile hydrophobic signaling compounds, which must navigate pathways that include both membrane and soluble enzymes. The insights these structures afford and the questions they engender are discussed in this minireview.
The effects of sodium, chloride, and calcium concentration on the response of melanophores to melanocyte-stimulating hormone (MSH).

Abstract Further studies have been conducted upon ionic factors influencing intermedin (MSH) action on the frog skin melanophore. The sodium requirement for MSH action is “absolute”, since none of a large series of monovalent cations are able to replace sodium. Replacement of chloride by other anions results in an inhibition of the response to MSH. In calcium-free media, there is an enhanced response to MSH. Furthermore, EDTA was found to darken frog skin. These results are discussed in terms of the hypothesis that MSH action involves an increase in the sodium content of the melanophore, followed by melanin dispersion.
Integrating elementary computational modeling and programming principles (abstract only)

We propose an approach to introduce computational models and basic programming principles in an integrated manner and as early as possible in the computing curricula. Our goal is to help educate students of computer science, mathematics, and the various science disciplines, in computational modeling. For this, we have developed a sequence of four courses in computational modeling, the first of which integrates computational modeling with programming principles and includes elementary numerical methods for solving the models. This entry-level course is described and a URL is provided with details of the four courses. Developing a computational model of a problem includes formulating the mathematical representation and implementing it by applying Computer Science concepts, principles and methods.
Organic Reactions in Gaseous Electrical Discharge I. Normal Paraffin Hydrocarbons

An apparatus is described for subjecting vapors to an electrical discharge. Vapor pressure and current are variable. Different fractions of the gaseous reaction products can be collected and their rates of accumulation measured. A study of n-decane vapor with this apparatus, with current values of from 0.5 to 2.5 m.a., voltage approxi mately 450 volts, and pressures from 0.2 to 4.5 mm of mercury, indicates that electric conduction in gases may follow an electrochemical equivalence law similar to Faraday's law of electrolytic conduction in liquids. Evidence has been obtained showing the amount of reaction to be proportional to the current, and independent of voltage and vapor pressure. Among the reaction products is a wax-like substance which deposits on the cathode only. The rate of production of gaseous reaction products has been measured for various values of discharge currents and vapor pressure. Curves and tables are given showing the relation between molecular size and rate of production of various fractions of the gaseous reaction products, for a series of seven normal paraffin hydrocarbons. A brief theoretical discussion is given.
Preoperative Psychological Preparation of the Child for Surgery: An Update

Preoperative anxiety is associated with a number of poor postoperative outcomes and with significant parental and child distress before surgery. Preparing children for surgery can prevent many behavioral and physiologic manifestations of anxiety. Psychologic and behavioral interventions and pharmacologic interventions are available to treat preoperative anxiety in children. This article discusses the psychologic preparation of children for surgery.
A brief introduction to the Internet

Abstract The Internet has changed the way science is performed. The upcoming changes to the Internet will change the way we live. This article will examine briefly the Internet, how it got to where it is, and where it might be going.
A design methodology for ships and other complex systems

A methodology for designing large multiunit, multipurpose ocean based systems is proposed. The methodology is in fact a disciplined procedure for selecting the system and its characteristics that will best satisfy the overall problem objective. The methodology addresses all stages of design of large systems from the design of a particular subsystem to the design of an overall system. Emphasis in this paper is on the exploratory phase of the proposed methodology.
Heterophase water-in-oil polymerization of acrylamide by a hybrid inverse-emulsion/inverse-microemulsion process

Heterophase water-in-oil polymerizations of acrylamide have been conducted in the presence of blends of non-ionic stabilizers at moderate monomer concentrations (20%). The initial monomeric system is located outside the inverse-microemulsion domain, yet close to the inverse-macroemulsion/inverse-microemulsion phase boundary. A turbid, viscous and unstable dispersion is produced at the outset and during the intermediate stages of the polymerization. This evolves to an inviscid and non-settling system at high conversions. Transparent inverse latices can also be produced provided that the polymerizations are conducted semi-adiabatically. Small angle neutron scattering (SANS) studies of the initial monomer and reacting systems have found the latices to be particulate with a particle diameter of 150 nm, independent of conversion. The SANS intensities can be fitted using a polydispese spherical particles model. Therefore, these heterophase water-in-oil polymerization systems seem to follow an inverse-macroemulsion-like mechanism. The ‘hybrid inverse-microemulsion/inverse-macroemulsion’ polyacrylamides produced herein have a smaller radius of gyration in aqueous media relative to those produced by either solution polymerization or a true inverse-macroemulsion polymerization of the same weight-average molecular weight. This is likely due to a large number of intramolecular interactions, such as hydrogen bonds, which are induced by the collapsed nature of the polymer chains in the inverse-microemulsion droplets. The weight-average molecular weight, the radius of gyration and the particle diameter of the final latex are relatively independent of the polymerizations conditions such as initiator level, hydrophilic-lipophilic balance (HLB), temperature and physical changes occurring during polymerization. From a kinetic point of view, the molecular weights of these systems are controlled by transfer to monomer, while transfer to interfacial emulsifier is the polymerization rate controlling step. A reaction mechanism consisting of a number of elementary reactions has been proposed for these heterophase-water-in-oil polymerizations. Agreement with the experimental data is found to be good at different levels of initiator, HLBs and temperature. Despite the limitations of this heterophase water-in-oil polymerizations (the moderate emulsifier levels, low radius of gyration and its inability to increase the weight-average molecular weight beyond 106 daltons), this polymerization process can produce final latices that are transparent and non-settling with small particles (< 150 nm). This allows post-reaction chemical modification, e.g. by the Mannich reaction.
Characterization of r.f.-sputtered ZnO thin films by X-ray diffraction and scanning electron microscopy

Abstract Thin films of ZnO, ranging in thickness from 0.08 to 6 μm, have been prepared by r.f. sputtering on substrates of either quartz or glass under various deposition conditions and subsequently characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results from XRD indicate that the grain size increases from 0.01 to 0.5 μm as the film thickness is increased from 0.08 to 6 μm for deposition at 65 °C and increases from 0.1 to 0.3 μm as the deposition temperature is increased from 65 to 480 °C for a constant film thickness of 2 μm, whereas the lattice strain and dislocation density decrease slightly under similar conditions. Results from SEM indicate that the particle size parallel to the plane of the film is approximately equal to the mean grain size perpendicular to the plane of the film, suggesting that growth proceeds by the nucleation of new grains rather than by the elongation of columnar grains in the growth direction. General observations indicate that microstructural parameters, such as grain size, grain shape and lattice strain, depend sensitively on the exact nature of the deposition conditions.
Analysis of two level atom in bichromatic field: Entropy flow and search for the Carnot cycle

We study the two-level atom interaction with bichromatic field to understand the entropy flow during this interaction in the absence of spontaneous emission. This flow is characterized by the Carnot cycle that demonstrates efficient cooling.
Spore age and coverslip placement affects germination and post-germination development of Colletotrichum dematium var circinans

Spore suspensions from young (10–14 da; young spores) and old (4 mo; old spores) colonies of PColletotrichum dematium var circinans were placed on slides. Coverslips were left off, placed on in the normal manner, or supported on shims. Slides were placed in moist chambers and incubated in light or dark for up to 48 hrs. Germination and post-germination development were studied. Shimming had some beneficial effect on germination, especially for old spores in dark. In general, more germ-tubes and appressoria were produced on spores under shims than spores with other coverslip treatments. By 48 hrs more old spores under shims germinated, and greater numbers of germ-tubes and appressoria were produced than on other old spores under different coverslip treatments. However, numbers produced were lower than those predicted for comparably treated young spores. Spore age, incubation regime, and placement of coverslips did not affect germ-tube initiation. For all treatments more germ-tubes were initiated from spore tops than bottoms or tips. Fewer germ-tubes were initiated from spore centers than other locations on tops and bottoms, and from both tips than one tip. Approximately 26 % of all appressoria were produced sessile. A higher percentage of sessile appressoria were produced on old spores (80 %) than on young spores (20%).
Numerical simulation of hot-electron effects on source-drain burnout characteristics of GaAs power FETs

Abstract A High Speed Semiconductor Device Analysis (HISSDAY) computer program, based on the energy transport model, is used to numerically analyze various GaAs FET structures to gain physical insights and to establish potential design criteria for minimization of burnout phenomena. A major finding is the relationship between the spatial distribution of hot electrons in the gate-drain region and the degree of burnout tolerance. FET structures which effectively prevent hot electrons from reaching the drain edge demonstrate high burnout power. Recessed-gate structures alone do not prevent hot electrons from reaching the edge of the drain electrode and therefore cannot prevent or minimize source-drain burnout. Gate-to-drain surface-field considerations also indicate that whereas recessed-gate designs improve gate-drain avalanche breakdown voltages, recessed-channel and n+ ledge designs tend to degrade gate-drain avalanche breakdown voltages. The combination of recessed gate and n+ ledge or recessed channel (double-recess structure) is a central feature to designs which minimize both gate-drain avalanche and source-drain burnout. A feedback-system model of the source-drain burnout mechanism for all FET structures simulated is proposed. Significant source-drain burnout voltage degradation at large gate biases near pinchoff is clarified in terms of the strong sensitivity of the hot electron energy-density distribution to channel opening in conventional MESFETs.
Self-Coaching: A Context-Sensitive, Person-Centred Approach to Social Communication After Traumatic Brain Injury

Unsuccessful social communication after traumatic brain injury (TBI) is often a consequence of self-regulatory (executive function) impairments. The primary goal of this article is to describe an approach to intervention for individuals with self-regulatory impairments that is individualised, sensitive to context and to the role of everyday communication partners, and supported by personally compelling metaphors. After a brief review of the social communication outcome literature, an innovative approach to improving social competence is presented and illustrated. The article ends with a review of the evidence base for social skills and self-talk interventions.
Mediating processes between stress and problematic marijuana use.

Abstract Background The literature widely reports that stress is associated with marijuana use, yet, to date, the path from stress to marijuana-related problems has not been tested. In this study, we evaluated whether negative affect mediates the relationship between stress and marijuana use. Methods To that end, we tested models to determine mediators between problems with marijuana use (via Marijuana Problem Scale), stress (via Early Life Stress Questionnaire, Perceived Stress Scale), and negative affect (via Beck Depression Inventory; Beck Anxiety Inventory) in 157 current heavy marijuana users. Mediation tests and bootstrap confidence intervals were carried out via the “Mediation” package in R. Results Depression and anxiety scores both significantly mediated the relationship between perceived stress and problematic marijuana use. Only depression significantly mediated the relationship between early life stress and problematic marijuana use. Early life stress, perceived stress and problematic marijuana use were significant only as independent variables and dependent variables. Conclusions These findings demonstrate that (1) depression mediated both early life stress and perceived stress, and problematic marijuana use, and, (2) anxiety mediated perceived stress and problematic marijuana use. This mediation analysis represents a strong first step toward understanding the relationship between these variables; however, longitudinal studies are needed to determine causality between these variables. To conclude, addressing concomitant depression and anxiety in those who report either perceived stress or early life stress is important for the prevention of cannabis use disorders.