cssi/SciSciGPT-SciSciNet huggingface dataset:
Mees' lines in a patient following acute arsenic intoxication.

A 62-year-old Turkish man developed nausea and vomiting 1 h following a dinner with friends and business associates. In the following few days, he developed dark urine, anemia, and thrombocytopenia. Five of his dinner companions developed similar symptoms of varying degrees, and one died. It is unknown how their food and beverage consumption differed during the meal. During the subsequent month, the patient developed gait ataxia, leg weakness, and burning pain and numbness in a glove-and-stocking distribution. Six weeks later, he traveled to the USA and was evaluated by our Department of Neurology. An electromyogram demonstrated generalized peripheral polyneuropathy, with motor and sensory axon loss. The patient was referred to the Department of Dermatology for evaluation of possible arsenic poisoning. Cutaneous examination revealed one transverse white band on several fingernails approximately 3–4 mm distal to the proximal nail fold, consistent with Mees’ lines (Fig. 1). A plaque of confluent 3-mm hypopigmented macules was evident on the extensor aspect of the left forearm (Fig. 2). Hair, nail, and urine samples were obtained to rule out heavy metal poisoning; the arsenic levels obtained were 27.6 µg/g (normal, 0.03–3 µg/g), 2.98 µg/g (normal, 0.03–3 µg/g), and 82 µg/L (normal, < 81 µg/L), respectively. Figure 1. Mees' lines present on the fingernails Figure 2. Hypopigmented macules on the forearm characteristic of “raindrops on a dusty road,” which developed after the arsenic intoxication These laboratory findings were consistent with acute arsenic poisoning. The patient was treated with oral succimer (water-soluble analog of dimercaprol), 10 mg/kg every 8 h, for 14 days with improvement of his neurologic symptoms. It is unknown exactly how the arsenic poisoning occurred, or the motivation behind it; however, criminal intent was suspected and is under investigation by the Turkish authorities.
Numerical transfer-matrix study of a model with competing metastable states

The Blume-Capel model, a three-state lattice-gas model capable of displaying competing metastable states, is investigated in the limit of weak, long-range interactions. The methods used are scalar field theory, a numerical transfer-matrix method, and dynamical Monte Carlo simulations. The equilibrium phase diagram and the spinodal surfaces are obtained by mean-field calculations. The model's Ginzburg-Landau-Wilson Hamiltonian is used to expand the free-energy cost of nucleation near the spinodal surfaces to obtain an analytic continuation of the free-energy density across the first-order phase transition. A recently developed transfer-matrix formalism is applied to the model to obtain complex-valued constrained'' free-energy densities [ital f][sub [alpha]]. For particular eigenvectors of the transfer matrix, the [ital f][sub [alpha]] exhibit finite-range scaling behavior in agreement with the analytically continued metastable free-energy density. This transfer-matrix approach gives a free-energy cost of nucleation that supports the proportionality relation for the decay rate of the metastable phase [Gamma][proportional to][vert bar]Im[ital f][sub [alpha]][vert bar], even in cases where two metastable states compete. The picture that emerges from this study is verified by Monte Carlo simulation.
Experimental study of opposed flow flame spread over wood fiber/thermoplastic composite materials

The results of an experimental investigation of flame spread over thermally thick composite samples are presented. The aim of the study is to establish the influences of material property variation and finite rate chemistry on the rate of spread and also to obtain the dependence of the chemistry factor on the oxygen mass fraction in the oxidizer flow. To this end, flame spread rates over samples inclined at various angles from the vertical direction are first measured in an oxygen environment and the results used to establish the sole influence of streamwise gravity on the spread process. A second set of flame spread tests are then performed using composites of various compositions within an oxidizer flow diluted with nitrogen. Finally, the results of both sets of experiments are incorporated into an existing flame spread rate formula to deduce the influences of material property variation and finite rate chemistry on the spread rate. The results show a good qualitative agreement with previous studies and produce new insights into the nature of the chemistry factor that can aid further development of the underlying theory.
Telencephalic lesions and behavior in the teleost Macropodus opercularis (l.): effects of telencephalon and olfactory bulb ablation on spawning and foamnest building.

Behavior during 5-day spawning trials of intact, sham-operated, olfactory bulb-ablated, and telencephalon-ablated male paradise fish, Macropodus opercularis, was investigated. Spawning and nestbuilding were eliminated in the telencephalon-ablated males and unimpaired in the sham-operated and olfactory bulb-ablated individuals. Telencephalon ablation resulted in decreased frequencies of frontal display, attack, and bubble blowing and differences in the probability of certain behavior sequences. The data indicate that the block of reproduction is a result of interference with nonolfactory functions of the telencephalon. Telencephalon ablation was previously reported to block spawning and foamnest building in male Macropodus opercularis (Davis et al., 1976). Lesioned males paired individually with intact females showed decreased frequencies of social behaviors at the start of the spawning trial, and during the trial they were subordinate to the female. The present study was undertaken to investigate in greater detail the effects of telencephalon ablation on reproductive behavior. The telencephalon ablation resulted in the destruction of the olfactory system. Olfactory stimuli strongly influence social behavior in fishes (Atema et al., 1969), including Macropodus (Rossi, 1969; Davis and Pilotte, 1975). The loss of olfaction rather than of nonolfactory functions of the telencephalon may be responsible for the block of reproduction. To examine this possibility we investigated the effects of olfactory bulb ablation on sociosexual behavior.
Patient aberrant drug taking behaviors in a large family medicine residency program: A retrospective chart review of screening practices, incidence, and predictors

Introduction: Potentially aberrant drug-taking behaviors (pADTB) are described as any departure from strict adherence to prescribed use of medications for their intended indication. There are several validated instruments, processes, and databases available to assist the clinician in screening and stratifying risk for patients in which controlled substances are being prescribed or considered. Actual utilization of these tools in nonspecialist healthcare settings is largely unknown. The primary objective of this retrospective chart review was to describe utilization patterns of these common tools within a 56 physician family medicine training program. Secondary objectives included identification of site-specific predictors of pADTB and correlation of prescribing patterns with documented aberrant behaviors. Methods: A total of 202 chronic pain patients were identified for inclusion based on prior 12-month prescription and refill records within the electronic health record (EHR) from March 2008 through March 2009. Each patient included had at least one opioid for 30 days within the study period and had chronic pain symptoms for at least 90 days. Each chart was reviewed for predefined pADTB, controlled substance refill request, prescription drug monitoring profile, and post hoc investigator completion of the Opioid Risk Tool Clinician Form. Descriptive statistics and regression analysis was used to report results. Results: Clinician documentation of risk-screening tool use of any type was limited to one patient of the 202 records reviewed. Within this sample, 203 unique pADTB were documented in the EHR records of 89 (44.1 percent) patients. Patients prescribed morphine or tramadol appeared to exhibit less use of multiple prescribers and multiple pharmacies while an association between this behavior and two or more concurrent opioid prescriptions became apparent. Those taking fentanyl or morphine exhibited unsanctioned dose escalations more frequently. Conclusions: These results suggest that routine evaluation of risk for abuse or misuse of opioid analgesics occurs infrequently in a large family medicine training program. pADTB exhibited by patients using opioids for chronic pain syndromes in this sample were consistent with those reported in other similar settings. Policies and procedures in primary care settings for improved risk evaluation and ongoing monitoring of chronic opioid therapy is needed.
Finite {ital W}-width and initial-state radiative corrections to the reaction e{sup +}e{sup {minus}}{r_arrow}W{sup +}W{sup {minus}}{r_arrow}l{sup +}l{sup {minus}}{nu}{nu}

Lepton-inclusive cross sections for the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{W}^{+}{W}^{\ensuremath{-}}\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}}\ensuremath{\nu}\ensuremath{\nu}$ are calculated. The influence of the radiative corrections and a finite decay W width is considered. Its large contribution to the total and, especially, differential cross sections of the final decay leptons is shown. The method to extract ${\ensuremath{\Gamma}}_{W},$ using the leptonic channel of W decay, is proposed.
PIEZOELECTRICITY IN INSULATORS

A microscopic theory is presented for the piezoelectric constants of zincblende. The theory is valid for ionic crystals. The constants have several contributions: one from long-range Coulomb interactions, and several from short range forces. The long-range term is given only by the dielectric function. The short-range terms are also large and nearly cancel the long-range terms: the largest is from the deformation-dipole term. The agreement between theory and experiment is a sensitive test of theories of short-range polarization in solids.
Effect of silica fume, metakaolin, and low-calcium fly ash on chemical resistance of concrete

Effects of aggressive chemical environments were evaluated on the mortars prepared with ordinary portland cement (OPC) and silica fume (SF)/metakaolin (MK)/low-calcium fly ash at various replacement levels. The natural adverse chemical environmental conditions were simulated using sulfuric acid, hydrochloric acid, nitric acid, acetic acid, phosphoric acid, and a mixture of sodium and magnesium sulfates. Chemical resistance information was used in conjunction with compressive strength measurements to propose realistic OPC/mineral admixture proportions.
The expanding role of on-line interactive searching

On-line interactive searching represents the newest thrust in information retrieval. The combined technologies make available to librarians and other information professionals large volumes of bibliographic data which reside in computers as remote as thousands of miles from the terminals using them. Presently the individual data bases that furnish the examples of actual usage (ERIC, NTIS, Psych Abstracts, etc.), are accessed primarily via Lockheed, SDC, Medline, and the SUNY Bio-Medical Network. Although it is difficult to give a definitive statement on the proportionate economic contribution of this kind of information retrieval to the entire computer economy, estimates of numbers of characters of information on-line (25--50 billions), indicate a significant dollar involvement. It is in this framework that bibliographically-oriented members of the computer community urge their non-bibliographic colleagues to understand information retrieval and to heed its requirements for further development.
Information Gathering and Technology Use Among Low-Income Minority Men at Risk for Prostate Cancer

Health communication researchers, public health workers, and health professionals must learn more about the health information-gathering behavior of low-income minority men at risk for prostate cancer in order to share information effectively with the population. In collaboration with the Milwaukee Health Department Men's Health Referral Network, a total of 90 low-income adult men were recruited to complete a survey gauging information sources, seeking behavior, use of technology, as well as prostate cancer awareness and screening behavior. Results indicated participants primarily relied on health professionals, family, and friends for information about general issues of health as well as prostate cancer. The Internet was the least relied on source of information. A hierarchical regression indicated interpersonal information sources such as family or friends to be the only significant predictor enhancing prostate cancer awareness, controlling for other sources of information. Prostate screening behaviors were predicted by reliance on not only medical professionals but also the Internet. Practical implications of the study are discussed.
On-Pump and Off-Pump Bypass Surgery Tools for Revascularization

Cardiopulmonary bypass (CPB) has been fundamental to the development of coronary bypass surgery. Although some early coronary operations were performed without CPB, widespread coronary surgery only occurred with the aid of perfusion, a support system that has allowed complex coronary reconstruction to be carried out with effective myocardial protection, end organ protection, and consistent and relative safety. See p 887 But CPB is not normal. Despite advances in perfusion technology, negative effects of CPB include blood trauma, activation of a series of inflammatory responses, nonpulsatile flow, and possible embolization of air or debris—most particularly embolization of atherosclerotic debris from the aorta. Within the last decade, increasing attention has been directed to the concept of decreasing perioperative risk by avoiding CPB: “off-pump” or “beating heart” bypass surgery. As a result of increased surgical experience and the development of enabling technology, such as stabilization and exposure devices, off-pump surgery has become increasingly feasible, and today, 20% to 25% of coronary operations in the United States are carried out without CPB. We now know that off-pump bypass surgery can be accomplished, but does it decrease risk, what risks are decreased, and for whom? As the off-pump concept moved into the surgical arena, the hope was that it would decrease perioperative morbidity and possibly mortality, and the fear was that revascularization would be more difficult, less complete, and less effective over the long term. Multiple studies have addressed these issues, including observational studies of large patient populations using statistical risk adjustment, observational trials of smaller patient subsets thought to specifically benefit from off-pump surgery, and randomized trials. All of these study designs suffer from some disadvantages. Nonrandomized studies have the disadvantages of bias in treatment selection and the possibility that differences in patient-related characteristics will mask the effect of surgical strategy, and randomized trials …
Preconditioned Krylov equation solvers in elastoplastic boundary element analysis

Abstract Nonlinear elastoplastic boundary element analysis (BEA) involves an algebraic subproblem requiring the solution of dense nonsymmetric matrix equations with an evolving right hand side vector. When multiple right hand side vectors are present, direct matrix triangular factorization techniques have been the compelling choice, amortizing the work of a single matrix factorization over the sequence of multiple fast ‘solutions’ of the resulting triangular systems. Recently, the superior performance of preconditioned Krylov equation solvers in linear BEA has also been documented. In this paper, the superior performance of preconditioned Krylov equation solvers is shown to be extendable to elastoplastic BEA. This is accomplished by exploiting the strategic reuse of the preconditioner, its factorization, and the Krylov vectors computed in the solution for the first right hand side vector, in the subsequent solution of matrix equations with multiple ‘nearby’ right hand side vectors. The details associated with this strategy are given, and the computer resources required in three dimensional elastoplastic BEA are used to quantify the computational efficiency associated with this new algorithm.
Beta A3/A1 crystallin from human cataractous lens contains an intramolecular disulfide bond.

PURPOSE. To develop an experimental approach that can identify amino acid sequences containing cysteine residues involved in disulfide bonding during cataractogenesis of the human lens. METHODS. Total proteins from cataractous and normal human lenses were solubilized anaerobically, followed by carboxymethylation of free sulfhydryl groups with iodoacetate. Carboxymethylated proteins were partially purified by reverse phase chromatography, then subjected to lys-C endoprotease digestion. Using reverse phase chromatography, each digest was resolved in the presence and absence of dithiothreitol (DTT), to identify peptides that were linked by disulfide bonds. These peptides were further characterized using a combination of Edman degradation and mass spectrometry. RESULTS. The reverse phase chromatography profiles of lys-C peptides from proteins of normal lenses were very similar in the presence and absence of dithiothreitol, while identical analysis of proteins from cataractous lenses demonstrated the presence ...
Decreased behavioral effects of daily intracerebroventricular bombesin

Intracerebroventricular (ICV) bombesin increases grooming and decreases food intake in rats. We examined tolerance to these effects by administering a daily injection of either saline or 25 ng bombesin to rats for 8 days via lateral ventricular cannulas. Food intake and grooming were monitored. After 8 days bombesin no longer increased grooming or decreased food intake in bombesin-treated rats, but did increase grooming and decrease food intake in saline-treated rats. This development of behavioral tolerance conflicts with previous reports using larger doses and demonstrates that repeated small doses of ICV bombesin produce different effects from larger doses.
Structuration, Biography Formation, and Knowledge: Observations on Port Growth during the Late Mercantile Period

The impact of human agency and constraining and enabling structural conditions on the growth of ports during the late mercantile period is addressed from three vantage points. Fernand Braudel's works on mercantile capitalism are reassessed. A prepositional summary of my own theory of place as historically contingent process is presented. Finally, the interplay of biography formation, knowledge acquisition, and the growth of Boston, Massachusetts, between 1783 and 1812 is considered.
Analysis methodology for single-pane windows used with high-velocity vehicles

Environmental conditions may adversely affect the optical performance of windows used in electro-optic (EO) imaging systems. Recent advances in the sophistication of optical software packages, coupled with finite element analysis (FEA) techniques, enabled the construction of a detailed window model. This model was used to analyze the window parameters that are affected by travelling through the atmosphere at high velocities. This paper presents the results of an analysis performed for a single-pane window used for operation in the mid infra-red (MIR) spectral region.
Laboratory tests in adults with monoarticular arthritis: can they rule out a septic joint?

UNLABELLED It is difficult to differentiate septic arthritis from other causes of monoarticular arthritis solely with a history and physical examination. The clinician must rely on ancillary tests to make a diagnosis, such as the white blood cell count of peripheral blood (WBC), the erythrocyte sedimentation rate (ESR), and the white blood cell count of the joint fluid (jWBC) obtained from arthrocentesis. Although it is known that septic arthritis is associated with abnormalities in these tests, the majority of the data are based on studies in the pediatric population. In addition, although several emergency medicine texts indicate that a jWBC greater than 50,000 cells/mm(3) is "positive," it is known that septic arthritis can occur in patients with low jWBCs. OBJECTIVES To determine whether specific ancillary tests have sufficiently high sensitivities to rule out septic arthritis in adults. METHODS This was a retrospective consecutive case series of patients from an urban emergency department (ED). Patients at least 18 years old who had septic arthritis confirmed by positive arthrocentesis culture or operative findings were included in the study. WBC greater than 11,000 cells/mm(3), ESR greater than 30 mm/hr, and jWBC greater than 50,000 cells/mm(3) were considered elevated. RESULTS Seventy-three patients met the inclusion criteria. The sensitivities of an elevated WBC, ESR, or jWBC in adults who had septic arthritis were 48%, 96%, and 64%, respectively. There were broad ranges of WBC, ESR, or jWBC among the patients. More than one third of adult patients with septic arthritis had jWBCs less than 50,000 cells/mm(3). All patients had an abnormality in at least one of these tests. CONCLUSIONS The WBC, ESR, and jWBC are extremely variable in adults with septic arthritis. Laboratory tests do not rule out septic arthritis with accuracy.
Effects of rearing temperature on sympathoadrenal activity in young adult rats

Animals reared at 18°C exhibit enhanced innervation of brown adipose tissue (BAT) and greater cold tolerance as adults, yet gain more weight when fed an enriched diet compared with rats reared at 3...
Terrestrial vegetation and the seasonal cycle of dissolved silica in a southern New England coastal river

The Pawcatuck river watershed (797 km2) is located in southern Rhode Island and northeastern Connecticut. The predominant lithology of the area is granite, and over 60% of the watershed remains forested with mixed hardwoods (primarily oak) and eastern white pine. As part of a larger study of nutrient and sediment exports from the watershed to Little Narragansett Bay, we measured dissolved silica (SiO2) (DSi) concentrations at the river mouth over 70 times between January 14, 2002 and November 29, 2002. Annual export of DSi during our study was 40 × 106 mol or 50 kmol km−2. The United States Geological Survey (USGS) obtained DSi concentrations at this site, at varying frequencies, from 1978 to the present, which allowed for a historical comparison of this study with previous years. River DSi concentrations exhibited a strong seasonal signal that did not vary in a regular way with water discharge or water temperature. DSi and dissolved inorganic nitrogen (DIN) concentrations were significantly related over the annual cycle (p<0.0001) and both decreased substantially during the spring. Dissolved inorganic phosphorus (DIP) did not covary at any time with silica or nitrogen, suggesting that in-stream biological uptake was not responsible for the seasonal decline in silica. The spring decline in river silica concentrations may be due to silica uptake by terrestrial vegetation. We estimate a net forest silica accretion rate of 41 kmol km−2 y−1, a value that is stoichiometrically consistent with other measurements of net carbon accretion in nearby forests.
Density matrix theory for calculating magnetization transfer and dynamic lineshape effects

NMR is a powerful tool for the study of chemical rate processes and the mechanisms by which they occur. Dynamic processes give rise to characteristic changes in transverse and longitudinal relaxation, which manifest themselves in the NMR lineshape and in magnetization transfer phenomena, respectively. Analysis of these effects permits the extraction of kinetic data. The mathematical theory central to this analysis is illustrated using the formalism of the density matrix for a two-spin system undergoing mutual intramolecular exchange in isotropic solution. The spin Hamiltonian and exchange operators are introduced, and the quantum mechanical equation of motion of the density matrix is presented, emphasizing those density matrix elements that correspond classically to longitudinal and transverse magnetization. The necessary Liouville and exchange superoperators are explicitly constructed from the corresponding Hamiltonian and exchange operators using tensor algebra. The equation of motion is then solved for the populations and single-quantum coherences to illustrate the origin of magnetization transfer and dynamic lineshape effects. The extension of the theory to arbitrarily large exchanging spin systems is addressed and illustrated for two mutually exchanging spins scalar coupled to a third spin. Finally, the two-spin lineshape calculation is fully worked out using a steady-state method that reduces the problem to the solution of a set of simultaneous algebraic equations.
Comparison of calculated and measured volumetric water content at four field sites

Abstract Terrestrial field dissipation studies are currently required as part of new active ingredient submission packages in many countries. Results from field dissipation studies are used to determine the fate of pesticides under field conditions which includes evaluation of compound degradation, mobility and other routes of dissipation. Time domain reflectometry (TDR) instrumentation has been helpful for determining if water movement through the soil profile was correlated with or was sufficient to cause compound mobility. A simple method is presented for estimating soil water flux from the soil profile using TDR technology. Additionally the question has been raised regarding how useful simple calculations of volumetric water content (VWC) can be for this purpose as well. A simple method of calculating VWC and profile flux are presented and compared to measurements using TDR and TDR based flux calculations. Results from this comparison indicate that calculated VWC estimates compare favorably with those based on actual TDR measurements. Calculated patterns of flux at a 120 cm depth based on TDR and the calculated VWC method correlate well, although the flux quantities can vary. Occurrence of flux from both methods were very similar, but quantities of flux were greater with the calculated VWC method compared to flux quantities based on the TDR calculation method. Additionally, because the calculated VWC method is computationally simple, the technique should also be useful for estimation of groundwater recharge at a regional scale using tools such as GIS.
Comparison of Microcontact-Printed and Solution-Adsorbed Cytochrome c Films on Indium Tin Oxide Electrodes

Three different methods for preparing cytochrome c (cyt c) films on planar indium tin oxide (ITO) electrodes have been characterized and compared using electrochemical and surface spectroscopy meth...
Novel amplification and transcriptional activity of chorion genes in Drosophila melanogaster follicle cells

Single-copy chorion genes coding for egg shell proteins are amplified in the follicle cells of Drosophila melanogaster egg chambers. Chromatin spreads of appropriately staged follicle cells reveal complex, multi-forked chromosomal structures in which one chromatin strand branches into two, which themselves branch out, and so on. In one micrograph, 13 strands originating from a single strand were observed. These structures can account for the maximal amplification occurring in the center of the domain, where the major chorion genes are located, and the decreasing amplification of flanking sequences to both sides. The amplification, high transcriptional rate, stage-specific expression, and correlation with known molecular sizes have allowed the putative identification of the single-copy, major chorion genes on the X chromosome and on chromosome III.
Coenzyme Q10 in the central nervous system and its potential usefulness in the treatment of neurodegenerative diseases

Coenzyme Q10 is an essential cofactor of the electron transport chain and is an antioxidant. We examined the effects of oral feeding with coenzyme Q10 in young animals on brain concentrations. Feeding with coenzyme Q10 at a dose of 200 mg/kg for 1-2 months in young rats resulted in significant increases in liver concentrations, however, there was no significant increase in brain concentrations of either reduced- or total coenzyme Q10 levels. Nevertheless there was a reduction in malonate-induced increases in 2,5 dihydroxybenzoic acid to salicylate, consistent with an antioxidant effect. In other studies we found that oral administration of coenzyme Q10 significantly reduced increased concentrations of lactate in the occipital cortex of Huntington's disease patients. These findings suggest that coenzyme Q10 might be useful in treating neurodegenerative diseases.
Age-related decline in the steroidogenic capacity of isolated rat Leydig cells: a defect in cholesterol mobilization and processing.

Abstract This study was designed to evaluate the effects of aging on steroidogenesis and intracellular cholesterol processing in rat Leydig cells. Maximum gonadotropin-induced testosterone secretion was significantly reduced in Leydig cells from 18 to 27-month-old rats compared to 2 to 5-month-old rats. The decreased production of testosterone in older groups persisted after incubation with cAMP analogs or other non-specific stimulatory agents. This age-related loss in testosterone response was not due to changes in gonadotropin receptor concentration, cAMP concentration, protein kinase A activation or the activity of key steroidogenic enzymes. The content of cellular cholesteryl esters doubled as rats aged from 5 to 18 months, and this high cholesteryl esters level remained constant through 27 months. The ability of hCG to mobilize (hydrolyze) stored cholesteryl ester for testosterone production was significantly reduced (65–75%) in cells from the older rats. This change could be accounted for by the decline in activity of neutral cholesteryl esterase in Leydig cells from 18-month-old rats. In contrast, the activity of a non-specific lysosomal acidic cholesteryl esterase did not change with age. The activity of HMG CoA reductase, the rate limiting enzyme in cholesterol biosynthesis decreased about 70% between 5 and 18 months and fell slightly further as the rats aged to 27 months. Also, [ 14 C]acetate or [ 3 H]H 2 O incorporation into cellular sterols showed a similar decline. Cyanoketone plus hCG stimulated pregnenolone production was reduced about 70–80% in old as compared to young cells. Leydig cells from young rats responded to hCG with increased accumulation of mitochondrial cholesterol in the presence and absence of steroidogenic inhibitors. On the other hand, old cells responded poorly to hCG and mitochondrial cholesterol levels were little affected by hCG plus cycloheximide or aminoglutethimide. Together, these data indicate that alterations in the intracellular processing and metabolism of cholesteryl esters occur in Leydig cells of aging rats, and we suggest they may be responsible for the observed age-related changes in testosterone production.
Characterization of phosphohydrolase activity in bovine spleen extracts: Identification of a bis(p-nitrophenyl)phosphate-hydrolyzing activity (phosphodiesterase IV) which also acts on adenosine triphosphate

Abstract Several bovine spleen enzymes with acid pH optima, some of which hydrolyze bis(p-nitrophenyl)phosphate and therefore fit the definition of “phosphodiesterase IV,” were partially separated by isoelectric focusing and ion-exchange techniques. The activities were characterized by zymogram analysis with the aid of p-nitrophenyl and 4-methylumbelliferyl phosphate and phosphonate substrates. A number of these enzymes meet the criteria for phosphodiesterase I or other phosphodiesterases. However, the predominant phosphodiesterase I hydrolyzes the bis(p-nitrophenyl)- and 4-methylumbelliferyl phosphates, p-nitrophenyl and 4-methylumbelliferyl phenylphosphonate, and ATP at the β-γ bond, but not p-nitrophenyl or 4-methylumbelliferyl 5′-thymidylate (the usual PDE I substrates). These properties, as well as the pH optimum, distinguish the activity from the previously described, alkaline pH optimum PDE I. A second phosphodiesterase hydrolyzes only the phenylphosphonates. Several other activities, less well described, are apparent on zymograms. None of the phosphodiesterases IV was also a phosphodiesterase II (no hydrolysis of 4-methylumbelliferyl 3′-thymidylate).
KINETICS OF ENZYMATIC HYDROLYSIS OF STEAM-EXPLODED COTTON GIN WASTE

The hydrolytic kinetics of cotton gin waste (CGW) at various initial concentrations of two enzymes, Novozymes NS50052 and Spezyme AO3117, was investigated. The experiments showed that the concentrations of reducing sugars increased with increasing initial enzyme concentration for the two enzymes. The reducing sugars produced per gram of Novozymes were higher than those produced by Spezyme. However, the reducing sugars produced per FPU of Novozymes were lower than those produced by Spezyme. The concentrations of reducing sugars reached 6.41 g/L and 4.93 g/L after seven hours of hydrolysis at the initial Novozymes enzyme loading of 12.3 filter paper unit (FPU)/g substrate and Spezyme loading of 3.68 FPU/g substrate, respectively. A two-parameter model based on enzyme deactivation and its analytical expression have been derived. The model was used to fit the experimental data of the hydrolytic kinetics of CGW. The enzyme deactivation rate constants in this model decreased as the initial enzyme concentration ...
Fresnel-Kirchhoff diffraction in optical systems: an approximate computational algorithm.

A method is outlined for approximation of scalar wave disturbances via the Fresnel-Kirchoff formula. While the method is limited to evaluating the disturbance along spherical reference surfaces, no particular inconvenience arises from this constraint in the context of many optical designs. The technique may readily be extended into the focal region. The fast Fourier transform is employed, making the computation time proportional to N logN, where N is the number of data points sampled in each wave front. Some examples are presented.
Changes in Fluent Aphasics' Performance following Therapy

Four fluent aphasics, varying in severity, were given twenty sessions of word-retrieval therapy. Twenty-four stimulus words were used across three tasks: comprehension, repetition, and confrontation naming. The stimulus words were also placed into four word variable categories for analysis. The categories were semantic, frequency of occurrence, pronounciability, and place of existence. Pretreatment performance measures on the three word-retrieval tasks and on two elicited conversation tasks were obtained for comparison to the same measures obtained after therapy. The severe patient did not improve on any tasks. The two moderate patients improved to almost 100% correct in daily word-retrieval and to 83.7% in the elicited conversation tasks. The mild aphasic with high pretreatment scores who maintained a flat high daily profile on word-retrieval tasks achieved a post-treatment score of 93.7% on the elicited conversation measures. Word variables were related to the pretreatment scores; however, minimal word ...
Nasal intubation: a minimally obtrusive anosmia technique applied to rats.

Abstract Nasal intubation represents a reversible, nonsurgical anosmia technique which produces little behavioral or physiological disruption. A polyethylene tube of sufficient length to extend from the narial opening past the various olfactory receptors is inserted into each nasal cavity. Thus, the animal can breathe freely through the tube, but the length of the tube prevents air from contacting olfactory receptors. To reverse the technique, the tubes are simply pulled out. The intubation technique was examined for the ability to produce anosmia with minimal nonolfactory behavioral disruption. Intubated animals lost the ability to perform olfactory discrimination, but completely regained olfactory discrimination ability once the tubes were removed. Controls for the effects of intubation on discriminative responding showed no deficit. Olfactory detection tests revealed intubated animals lost the ability to locate buried, scented food. Controls for the effects of intubation showed no deficit in olfactory detection. Open field tests, daily weight records, and subjective judgments of ease of handling, used to assess the secondary effects of intubation, showed no significant effect of intubation.
Rapid filtration measurements of Ca2+ release from cisternal sarcoplasmic reticulum vesicles.

Abstract A radioactive tracer and rapid filtration method was applied to the study of Ca 2+ release from sarcoplasmic reticulum (SR) vesicles which were preloaded passively (equilibration with millimolar Ca 2+ ) or actively (in the presence of ATP or acetyl phosphate). The method allows complete substitution of the loading mixture with release medium in constant flow, and time resolution between 0.01 and 10.0 s. Net release can be clearly distinguished from isotope exchange. The latter is prominent in longitudinal SR vesicles. Net Ca 2+ release is observed only from cisternal SR vesicles, is Ca 2+ (micromolar) dependent, and is accelerated by inactive ATP analogues, or ATP itself, even in the presence of Mg 2+ . Net release has a strong pH dependence (between 6 and 7), and very little temperature dependence (consistent with a passive channel). In media of physiological significance (1 mM ATP, 1 mM magnesium, and free Ca 2+ in the micromolar range), net Ca 2+ release proceeds with a rate constant of approx. 100 s −1 .
How competitive is my surgical specialty

Abstract Background: It is difficult to determine relative competitiveness of surgical training positions: there is no single source for matching process results and specialty-specific competitiveness may change over time. This study was undertaken to address these issues. Methods: Numbers of matched/unmatched students and positions offered/filled for surgical specialties were analyzed for specialty-specific trends in match rates and differences among specialty match rates over time. Results: From 1996 to 2000, match rates increased for neurological surgery, general surgery and otolaryngology; decreased for ophthalmology and urology and were unchanged for orthopedic surgery. Although the “most competitive” and “least competitive” specialties changed each year, unmatched student numbers uniformly exceeded unfilled position numbers. Conclusions: Match rates changed over time; no single specialty was consistently most or least competitive. Unmatched students were unlikely to successfully “scramble” for an advanced/categorical training position in any surgical specialty because of the uniformly very high fill rates.
HyDA-Vista: towards optimal guided selection of k-mer size for sequence assembly

Intimately tied to assembly quality is the complexity of the de Bruijn graph built by the assembler. Thus, there have been many paradigms developed to decrease the complexity of the de Bruijn graph. One obvious combinatorial paradigm for this is to allow the value of k to vary; having a larger value of k where the graph is more complex and a smaller value of k where the graph would likely contain fewer spurious edges and vertices. One open problem that affects the practicality of this method is how to predict the value of k prior to building the de Bruijn graph. We show that optimal values of k can be predicted prior to assembly by using the information contained in a phylogenetically-close genome and therefore, help make the use of multiple values of k practical for genome assembly. We present HyDA-Vista, which is a genome assembler that uses homology information to choose a value of k for each read prior to the de Bruijn graph construction. The chosen k is optimal if there are no sequencing errors and the coverage is sufficient. Fundamental to our method is the construction of the maximal sequence landscape, which is a data structure that stores for each position in the input string, the largest repeated substring containing that position. In particular, we show the maximal sequence landscape can be constructed in O(n + n log n)-time and O(n)-space. HyDA-Vista first constructs the maximal sequence landscape for a homologous genome. The reads are then aligned to this reference genome, and values of k are assigned to each read using the maximal sequence landscape and the alignments. Eventually, all the reads are assembled by an iterative de Bruijn graph construction method. Our results and comparison to other assemblers demonstrate that HyDA-Vista achieves the best assembly of E. coli before repeat resolution or scaffolding. HyDA-Vista is freely available [1]. The code for constructing the maximal sequence landscape and choosing the optimal value of k for each read is also separately available on the website and could be incorporated into any genome assembler.
Biomarker Discovery for Risk Stratification of Cardiovascular Events using an Improved Genetic Algorithm

Detection of an optimal panel of biomarkers capable of predicting a patient?s risk of major adverse cardiac events (MACE) is of clinical significance. Due to the high dynamic range of the protein concentration in human blood, applying proteomics techniques for protein profiling can generate large arrays of data for development of optimized clinical biomarker panels. The objective of this study is to discover a panel of biomarkers for predicting risk of MACE in subjects reliably. The development of immunoassay can only tolerate the complexity of the prediction model with less than ten selected biomarkers. Hence, traditional optimization methods, such as genetic algorithm, cannot be used to derive a solution in such a highdimensional space. In this paper, we propose an improved genetic algorithm with the local floating searching technique to discover a subset of biomarkers with improved prognostic values for prediction of MACE. The proposed method has been compared with standard genetic algorithm and other feature selection approaches based on the MACE prediction experiments.
Effects of Cooperative Learning On the Social Acceptance of Mainstreamed Academically Handicapped Students

Studies examining relationships between children with learning problems and their peers have consistently indicated that learning-disabled and educable-mentally-retarded students have fewer friends and are more frequently rejected by their classmates than are other students. In previous research, cooperative classroom structures have been shown to promote positive relationships among peers. In this study, 6 classes enrolling academically handicapped and normal-progress children were randomly assigned to study mathematics cooperatively or under a traditional classroom structure. Results indicated that cooperative techniques improved social acceptance in that rejection of academically handicapped students was decreased, but friendships were not increased. Academic achievement gains and increases in self-esteem were found for the combined sample of students in the cooperative learning treatment.
Saturation of second harmonic generation in plasmon-coupled GaAs-filled hole arrays

Second harmonic generation (SH) based on the enhancement of localized fields confined in nanoscale periodic, GaAs-filled holes in a metal film is presented. The SH saturates for a fundamental peak power intensity Gt 20 GW/cm2.
Actuarial Analysis of Patient Survival and Dropout With Various End-Stage Renal Disease Therapies

Life table analyses were applied to experiences at the University of Missouri over a 5-year period with center hemodialysis, home hemodialysis, continuous ambulatory peritoneal dialysis (CAPD), living related donor transplantation, and cadaveric transplantation. Patient survival, graft survival, and persistence on therapy were analyzed. Mean ages and the percentage of insulin-treated diabetics were not similar in all groups; many factors influenced the choice of therapy by patient and physician. Nevertheless, the results show the net outcomes of these different therapies at an institution that has offered them all over the 5-year period analyzed. Patient survival and persistence on therapy for CAPD fell within the range of the other forms of therapy. Based on predictions of patient survival from published experiences with end-stage renal disease (ESRD) populations, observed survivals in CAPD were close to those predicted for the age of the population. At 2 years, persistence on therapy (technique survival) was similar for center hemodialysis and CAPD. However, 88% of the nondeath dropouts from center hemodialysis were for kidney transplantation, while 12% were related to technique problems. In contrast, in CAPD only 14% of the nondeath dropouts were for a kidney transplantation, 10% were based on recovery of renal function, and 76% were related to dialysis therapy problems. Nondeath dropouts from home hemodialysis were more similar to those in CAPD, with only 33% for kidney transplantation and 67% for therapy problems. These results cannot be assumed to indicate that the choice of therapy influences outcome. They show net outcomes in a single program are most likely based on multiple factors (age, diabetes mellitus, cardiac status, patient selection bias, physician selection bias, and perhaps the therapy per se) that influence these indices of success. To our knowledge these are the first comparisons of the net outcomes of all these forms of therapy at a single institution over the same period of time.
Host Specificity of Salmonella typhimurium Deoxyribonucleic Acid Restriction and Modification

The restriction and modification genes of Salmonella typhimurium which lie near the thr locus were transferred to a restrictionless mutant of Escherichia coli. These genes were found to be allelic to the E. coli K, B, and A restriction and modification genes. E. coli recombinants with the restriction and modification host specificity of S. typhimurium restricted phage lambda that had been modified by each of the seven known host specificities of E. coli at efficiency of plating levels of about 10(-2). Phage lambda modified with the S. typhimurium host specificity was restricted by six of the seven E. coli host specificities but not by the RII (fi(-) R-factor controlled) host specificity. It is proposed that the restriction and modification enzymes of this S. typhimurium host specificity have two substrates, one of which is a substrate for the RII host specificity enzymes.