cssi/SciSciGPT-SciSciNet huggingface dataset:
Tobacco-Specific Nitrosamines (NNAL, NNN, NAT, and NAB) Exposures in the US Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014)

Introduction The tobacco-specific nitrosamines (TSNAs) are an important group of carcinogens found in tobacco and tobacco smoke. To describe and characterize the levels of TSNAs in the Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014), we present four biomarkers of TSNA exposure: N'-nitrosonornicotine, N'-nitrosoanabasine, N'-nitrosoanatabine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) which is the primary urinary metabolite of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Methods We measured total TSNAs in 11 522 adults who provided urine using automated solid-phase extraction coupled to isotope dilution liquid chromatography-tandem mass spectrometry. After exclusions in this current analysis, we selected 11 004 NNAL results, 10 753 N'-nitrosonornicotine results, 10 919 N'-nitrosoanatabine results, and 10 996 N'-nitrosoanabasine results for data analysis. Geometric means and correlations were calculated using SAS and SUDAAN. Results TSNA concentrations were associated with choice of tobacco product and frequency of use. Among established, every day, exclusive tobacco product users, the geometric mean urinary NNAL concentration was highest for smokeless tobacco users (993.3; 95% confidence interval [CI: 839.2, 1147.3] ng/g creatinine), followed by all types of combustible tobacco product users (285.4; 95% CI: [267.9, 303.0] ng/g creatinine), poly tobacco users (278.6; 95% CI: [254.9, 302.2] ng/g creatinine), and e-cigarette product users (6.3; 95% CI: [4.7, 7.9] ng/g creatinine). TSNA concentrations were higher in every day users than in intermittent users for all the tobacco product groups. Among single product users, exposure to TSNAs differed by sex, age, race/ethnicity, and education. Urinary TSNAs and nicotine metabolite biomarkers were also highly correlated. Conclusions We have provided PATH Study estimates of TSNA exposure among US adult users of a variety of tobacco products. These data can inform future tobacco product and human exposure evaluations and related regulatory activities.
Trends in the prevalence of kidney stones in the United States from 2007 to 2016

The overall prevalence of kidney stones (KS) in the US rose from 3.2% in 1980 to 10.1% in 2016, but the trends in important subgroups have not been reported. We examined the prevalence trends of KS in subgroups of age, sex and race in the US and identified relevant laboratory factors associated with a history of KS using National Health and Nutrition Examination Survey (NHANES) data. We conducted a cross-sectional study among 28,209 US adults aged ≥ 20 years old in the NHANES from 2007 to 2016. We calculated the prevalence of a self-reported history of KS by using weights and standardized to the 2010 US Census population. We also compared relevant laboratory values according to the history of KS. The prevalence of KS decreased from 8.7% in 2007–2008 to 7.2% in 2011–2012 but then increased to 9.0% in 2013–2014 and 10.1% in 2015–2016. However, the overall prevalence of KS increased over 2007–2016 (p-trend = 0.02). Prevalence of KS among men was higher than women. Among men aged 20–79, there were significant quadratic trends in the prevalence of KS. Whereas, the prevalence of KS increased as a linear trend among women aged 20–59 years over 2007–2016. There were no consistent trends in the prevalence of KS by race. The prevalence trend of KS among non-Hispanic whites was 9.8% from 2007 to 2010 then dropped to 7.9% in 2011–2012 and increased to 10.6% in 2013–2014 and 12.1% in 2015–2016. A similar trend was also observed among non-Hispanic blacks. Among Hispanic, the prevalence of KS was 7.6% in 2007–2008 and 7.4% in 2009–2010 and then fluctuated over the next several time periods. For non-Hispanic Asians, the range was 4.4–4.6%. Regarding relevant laboratory factors, after adjusting for sex, race, age, BMI, smoking status, alcohol drinking, history of diabetes and gout, urine albumin-creatinine ratio and serum osmolality were independently associated with the history of KS in women and men. In conclusion, there was substantial variability in KS prevalence across individual 2-year time periods. This variation of period-specific prevalence values emphasizes the importance of looking at long-term trends and using more than a single 2-year cycle in analyses to increase the precision of the estimate. However, there was an overall increase in the prevalence of KS over 2007-2016.
How frequently does hepatocellular carcinoma develop in at-risk patients with a negative liver MRI examination with intravenous Gadobenate dimeglumine?

To determine the rate of development of clinically significant liver nodules (LR-4, LR-5, LR-M) after a negative MRI in an HCC screening population. This retrospective study included patients at risk of developing HCC requiring imaging surveillance who had undergone multiphase Gadobenate dimeglumine-enhanced MRI that was negative and had follow up LI-RADS compliant multiphase CTs or MRIs for at least 12 months or positive follow-up within 12 months. Follow-up examinations were classified as negative (no nodules or only LR-1 nodules) or positive (nodule other than LR-1). Time-to-first positive examination, types of nodules, and cumulative incidence of nodule development were recorded. 204 patients (mean age 58.9 ± 10.2 years, 128 women), including 172 with cirrhosis, were included. Based CT/MRI follow-up (median 35 months, range 12–80 months), the overall cumulative incidence of developing a nodule was 10.5%. Cumulative incidence of nodule development was: 0.5% at 6–9 months and 2.1% at 12 ± 3 months, including one LR-4 nodule, one LR-M nodule, and two LR-3 nodules. The cumulative incidence of clinically significant nodule development was 1.1% at 9–15 months. 70% (143/204) of patients also underwent at least one US follow-up, and no patient developed a positive US examination following index negative MRI. Clinically significant liver nodules develop in 1.1% of at-risk patients in the first year following negative MRI. While ongoing surveillance is necessary for at-risk patients, our study suggests than longer surveillance intervals after a negative MRI may be reasonable and that further research is needed to explore this possibility.
An Unusual Clinical Presentation of Immunoglobulin A Vasculitis in an Elderly Patient

Immunoglobulin A (IgA) vasculitis (IgAV), also known as Henoch-Schonlein purpura, is an IgA-mediated leukocytoclastic vasculitis predominantly affecting the gastrointestinal tract, kidneys, and skin. IgAV appears to be more common in children and is relatively rare in the adult population. We describe a case of a 72-year-old man who presented with bilateral lower extremity swelling, nausea, vomiting, abdominal pain, and weight loss, in which a diagnosis of IgAVs was established with a skin biopsy. This case highlights a rare and unusual clinical presentation of IgAV in an older patient and the need for prompt diagnosis and treatment.
Registered Dietitian Staffing in Dialysis: Impact on Quality Ratings in Mandate and Nonmandate States.

Objective Texas is the only state to mandate a patient to full-time equivalent (FTE) registered dietitian (RD) ratio ( Design and Methods Using data from Dialysis Facility Annual Reports, we excluded facilities with less than 125 patients and matched based on region, chain/profit status, and number of patients, pairing each Texas facility with 2 non-Texas facilities. T-tests for difference of means and chi-square tests were performed to compare facility groups characteristics and assess mandate impact. We used correlation between patient:FTE RD ratio and staff quality linearized score, and ANOVA to compare patient:FTE RD ratios between the star rating levels. Results The patient:FTE RD ratio was higher in non-Texas than Texas facilities (111.84 ± 40.70 vs 90.80 ± 24.02, P Conclusion The mandate effectively lowered the patient:FTE RD ratio in Texas dialysis facilities with over 125 patients, indicating that states considering such a mandate may benefit from implementing it. We found no association between patient:FTE RD staffing and quality, either objectively or via patient assessment. Further research should examine whether dialysis facilities are trending toward smaller patient sizes to circumvent staffing mandates and examine the relationship between other professions' staffing ratios and quality.
Changes in treatment of community-onset Clostridioides difficile infection after release of updated guidelines, Atlanta, Georgia, 2018

Abstract Updated Clostridioides difficile infection (CDI) guidelines published in 2018 recommend vancomycin as first-line treatment. Of 833 community-onset CDI cases in metropolitan Atlanta, Georgia in 2018, over half did not receive first-line treatment, although guideline adherence increased over the year. Second-line treatment was more common in patients treated in ambulatory settings.
Advanced Analytic Number Theory: L-Functions

Hecke L-functions Artin-Hecke L-functions Analytic properties of L-functions The explicit formulas Bounds on discriminants and conductors Non-vanishing theorems The local theory of root numbers: A survey Bibliography Index Hecke L-functions Artin-Hecke L-functions Analytic properties of L-functions The explicit formulas Bounds on discriminants and conductors Non-vanishing theorems The local theory of root numbers: A survey Bibliography Index
Approximate optimal closed loop control of nonlinear systems via parameter search

Abstract : The purpose of the paper is to present a simple straight-forward procedure for obtaining a near optimal closed loop algorithm for nonlinear system and compare it with linear design via optimal control theory. (Author)
HETEROGENEITY OF FOREST CHARACTERISTICS IN PRIMARY AND SECONDARY FOREST STANDS ON THE THIRD CHICKASAW LOESS BLUFF, TENNESSEE

In this study, non-spatial and spatial components of heterogeneity were contrasted for a mid-successional forest (55 years old) and an adjacent primary forest in western Tennessee. Analyses of size-class frequencies showed that whereas all size classes were well represented in the primary forest, the second-growth stand was marked by a greater number of canopy/subcanopy–level (10 to 50 cm dbh) trees but fewer understory individuals, especially in the 2 to 4 cm dbh size class. Variability of basal area, maximum tree size, and understory diversity was greater for the primary stand, whereas variability of overstory (>10 cm dbh) tree density and diversity was higher on the secondary stand. Plot aggregations, species-accumulation curves, and semivariogram analysis indicated differences in the scale of patterns of forest structure and composition between the two stands. These differences apparently are related to the smaller crown sizes of maturing trees and the denser packing of canopy individuals in the secon...
Transparent Absorbing Boundary (TAB): In-Domain Computational Domain Truncation

To truncate an unbounded space, a variety of techniques have been proposed [1–3]. Figure 1 shows a diagram of a traditional finite computational domain. Apparently, the presence of the transition domain increases the computational cost in the solution of the fields within the subject domain. The popular Perfectly Matched Layer (PML) [4] provides a virtually reflection-free absorbing technique that makes it possible to reduce the thickness of the transition region. However, it still needs the additional domain to absorb the outward traveling waves.
Phylogeny of Aulacoseira (Bacillariophyta) based on molecules and morphology

The phylogeny of 67 populations representing 45 species of Aulacoseira Thwaites was estimated by maximum parsimony methods using a combination of nucleotide sequence data and qualitative and quantitative morphological characteristics of the silica cell wall gathered primarily from original observation by LM and SEM. A new type of character using continuous quantitative variables that describe the ontogenetic-allometric trajectories of cell wall characteristics over the life cycle (size range) of diatoms is introduced. In addition to the 45 Aulacoseira species, the phylogeny also incorporated one Miosira Krammer, Lange-Bertalot, and Schiller species and two outgroup species (Melosira varians Agardh and Stephanopyxis nipponica Gran & Yendo). Fifteen species, represented by 24 populations, also contained molecular data from the nuclear genome (18S rDNA), and 11 of these species (18 populations) contained data from the chloroplast genome (rbcL) as well, which were sequenced or downloaded from GenBank. The phylogeny of Aulacoseira is composed of five major clades: 1) an A. crenulata (Ehrenburg) Thwaites and A. italica (Ehrenburg) Simonsen clade, which is the most basal; 2) an A. granulata (Ehrenburg) Simonsen complex clade; 3) an A. ambigua (Grunow) Simonsen clade; 4) an A. subarctica (O. Muller) Haworth and A. distans (Ehrenburg) Simonsen clade; and 5) an A. islandica (O. Muller) Simonsen clade that also contained endemic species from Lake Baikal, Siberia and many extinct Aulacoseira taxa. Monophyly of Aulacoseira can only be achieved if Miosira is no longer given separate generic status.
Permeability criteria for effective function of passive countercurrent multiplier

The urine concentrating effect of the mammalian renal inner medulla has been attributed to countercurrent multiplication of a transepithelial osmotic difference arising from passive absorption of N...
A slicing algorithm for rapid prototyping and manufacturing

This paper first reviews the existing techniques of surface-plane intersection in computer-aided geometric design (CAGD). The vector fields are introduced for the detection of closed intersection loops. A distance function is defined from a surface patch to an intersecting plane and the gradient of the function defines a plane vector field. The Poincare index theorem is inconclusive in detecting critical points of plane vector field. The modified Poincare theorem is developed by extending the plane vector fields into three dimensions for the conclusive test of critical points. The initial points are obtained based on loop detection and subdivision. The resulting intersections are represented using biarc spline fitting scheme. The algorithm presented in the paper requires only the surface be parametrically defined and C/sup 2/ continuous.
India’s Trilemma: Financial Liberalisation, Exchange Rates and Monetary Policy1

A key challenge for macroeconomic policy in open economies is how to simultaneously manage exchange rates, interest rates and capital account openness – the trilemma. This study calculates a trilemma index for India and investigates its evolution over time. We find that financial integration has increased markedly after the mid-2000s, with corresponding limitations on monetary independence (MI) and exchange rate stability (ES). In addition, we empirically confirm that a rise in one trilemma variable is traded off with a drop in the weighted sum of the other two, i.e. the trilemma configuration is binding in India. Finally, we consider the implications of changes in the trilemma index for macroeconomic outcomes. We find that greater MI systemically contributes to lower inflation, so the twin goals of ES and capital account openness may create policy dilemmas in particular economic environments. ES is associated with less inflation volatility, suggesting that there may be secondary benefits channelled through import and commodity prices. In these relationships, however, changes in international reserves are not statistically significant, suggesting that foreign exchange market intervention has not mitigated the trilemma trade-off in India.
Mitochondrial DNA Restriction Map for the Mediterranean Fruit Fly, Ceratitis capitata

Molecular genetic research on the Mediterranean fruit fly,Ceratitis capitata, will provide tools to permit determination of source populations for new pest infestations. Restriction fragment length polymorphism (RFLP) of mitochondrial DNA provides some interpopulation discrimination. A restriction map, including the informative variableEcoRV andXbaI restriction sites, is constructed for the Mediterranean fruit fly, and several restriction sites are associated with specific gene regions based on polymerase chain reaction-RFLP and sequence analyses. A partial sequence of the mitochondrial 16S ribosomal RNA gene is reported.
Siting and Stability of Metal Cations in Zeolites

Zeolites containing cation-exchanged transition metal cations are effective catalysts for a variety of reactions. The distribution of metal cations amongst different cation-exchange sites depends on a variety of factors including, the charge on the cation, the Si/Al ratio of the zeolite, and the distribution of Al atoms in the zeolite framework. An overview is presented of recent theoretical efforts aimed at determining the distribution of charge- exchange sites in ZSM-5 as a function of Si/Al ratio and the stability of mono- and divalent cations located at specific charge-exchange sites. Stability is defined with reference to either reduction to metallic particles or demetallation to form metal oxide particles. The siting requirements and stability of binuclear cations, viz. [M-O-M]2+, are also examined.
Current issues and controversies in capital punishment

Editorial IntroductionIt is our pleasure to introduce you to our special issue on "Current Issues and Controversies in Capital Punishment". Capital punishment continues to be one of the most highly debated and polarizing public policies issues in the United States. But, the number of individuals on death row has reached an almost twenty year low, many states have moratoriums on capital punishment, while others have repealed the use of the death penalty altogether (Death Penalty Information Center, 2014, 2013a). At the same time, thirty-two states continue to use capital punishment and as of this writing, twenty individuals have been executed in 2014 (Death Penalty Information Center, 2013b).Social science research often enters the capital punishment debate through studies examining the influence of legal and extralegal characteristics on prosecutorial decisions to seek the death penalty (e.g., Paternoster, 1984; Paternoster & Brame, 2003), jury death sentence decision-making (e.g., Jen... Language: en
Differential effects of amphetamine transport vs. dopamine reverse transport on particulate PKC activity in striatal synaptoneurosomes.

Amphetamine has been shown to increase striatal particulate protein kinase C (PKC) activity [Giambalvo (1992b) Neuropharmacology 31:1211-1222]. The present study examined possible mechanisms involved. Specifically, the effects of calcium, endogenous DA, and DA receptors on the amphetamine-induced increase in PKC activity in striatal synaptoneurosomes were examined. Naive rats and rats pretreated with N-ethoxy-carbonyl-2-ethoxy-1,2-dihydroquinolone (EEDQ, i.p.), a nonselective irreversible receptor antagonist, or with alpha-methyl-p-tyrosine (AMPT, i.p.), a DA synthesis inhibitor, were sacrificed and striatal synaptoneurosomes were prepared. The tissue was incubated with amphetamine, with and without calcium, and PKC activity was then determined by the endogenous phosphorylation of endogenous substrate proteins, as described previously [Giambalvo (1988a) Biochem Pharmacol 37:4001-4007]. It was found that calcium enhanced the effect of amphetamine on PKC activity, even in rats pretreated with EEDQ. Intracellular calcium was required since pretreatment with 1,2-bis (2-aminophenoxy) ethane-N, N, N, N-tetracetic acid acetoxymethyl ester (BAPTA-AM) in vitro attenuated the amphetamine-induced increase in PKC activity, resulting in an inhibition of PKC activity instead. Likewise, endogenous DA was essential since pretreatment with AMPT resulted in a similar amphetamine-induced inhibition of PKC activity. Pretreatment with AMPT did not alter the inhibitory effect of the D2 DA agonist, LY 171555, on PKC activity. It did, however, abolish the calcium-dependent stimulatory effect of the D1 agonist SKF 38393 on PKC activity, rendering it inhibitory regardless of calcium. Considering that both BAPTA-AM and AMPT pretreatments, which diminished DA release without affecting uptake via different mechanisms, produced similar inhibitory effects on PKC activity by amphetamine, these results suggest that the inward transport of amphetamine had an inhibitory effect on PKC activity. In contrast, the outward transport of DA seemed to have a stimulatory effect on PKC activity since incubation with low sodium or with ouabain, conditions that promote DA reverse-transport, increased PKC activity. These results showed that PKC activity was altered differently during inward vs. outward transport. The amphetamine-induced increase in PKC activity was attenuated by pretreatment with DA uptake blockers (nomifensine, GBR 12935, and bupropion), even though these drugs by themselves also increased PKC activity. This effect was diminished by calcium and persisted in rats pretreated with EEDQ. Thus, calcium had a differential effect on the PKC activity induced by a transported substrate (amphetamine) vs. nontransported inhibitors (DA uptake blockers).
Deep Eustatic Terrace Levels: Further Speculations

Criteria for recognizing the maximum glacial eustatic lowering of sea level during Pleistocene time depend on the interpretation of terrace features on high-energy coastlines in structurally stable regions of relatively low sedimentation. A variety of factors favor the Bering shelf and southern Australia as areas likely to retain evidence of a deep terrace record. In both localities, there is strong morphologic evidence for a continuous terrace along the upper continental slope at about 240 m. Intermediate terraces are also displayed at about 165 and 200 m below a very uniform shelf-edge break at 146 m. A eustatic lowering of sea level to approximately 240 m is supported by deep submersible observations of terraces and gravel accumulations off lower California, subaerial erosion features on carbonate banks, and survey data from selected shallow seamounts.
Adaptive subchip multipath resolving for wireless location systems

Reliable positioning of cellular users in a mobile environment requires accurate resolving of overlapping multipath components. However, this task is difficult due to fast channel fading conditions and data ill-conditioning, which limit the performance of least-squares-based techniques. This paper develops two overlapping multipath resolving methods (adaptive and nonadaptive), and shows how the adaptive solution can be made robust to the above limitations by extracting and exploiting a priori information about the fading channel. Also the proposed techniques are extended when there are antenna arrays at the base station. Simulation results illustrate the performance of the proposed techniques.
Stabilized ruthenium catalysts supported on magnesium oxide: Formation of a novel surface complex

During the past decade, much effort has been expended in the search for catalysts capable of abating the automotive pollutants NO,, CO and unburned hydrocarbons. It has been found that the latter two can be reduced to acccptablc levels by oxidation over a Pt/Pd catalyst, and this has been dcvcloped to the point of commercialization. With regard to nitrogen oxides, howcvcr, the problem has turned out to bc more difficult. A number of substances are able to catalyze the reduction of NO,, all of which require reducing conditions.’ The presently contemplated dual-bed system would incorporate a NO,-reduction catalyst, operating in a reducing atmosphcrc, followed by air injection to provide an oxidizing atmosphere for combustion of CO and hydrocarbon over the oxidation catalyst. A three-way catalyst which can simultaneously reduce NO, and oxidize CO and hydrocarbons is also conceivable if careful control of the air/fuel ratio can be achieved.
Postnatal development of eustachian tube cartilage. A study of normal and cleft palate cases.

Infants with cleft palate (CP) display eustachian tube (ET) dysfunction. This study compared the postnatal development of the volume of ET cartilage in 34 normal cases and 10 CP cases using a personal computer. In cases with age under 1 month old, the total volume of ET cartilage was 61.94±20.89 mm3 (mean±S.D.) in 16 normal control cases and 50.07±24.69 mm3 in nine CP cases (t-test, not significantly different from normal). The ratio of lateral lamina (LL) to medial lamina (ML) volume (LL/ML) was reduced significantly (t-test, P<0.001) from 0.23±0.07 in 16 normal control cases to 0.09±0.05 in nine CP cases under 1 month old. In 34 normal ET cases whose ages were under 20 years, statistically significant positive correlations were found between the total volume of ET cartilage (y1) and age (x), volume of LL (y2) and age, and volume of ML (y3) and age (P<0.01, r=0.731, 0.614, 0.719). The regression lines were y1=20.37x+95.57, y2=2.02x+15.60, and y3=18.35x+79.97. With the result obtained from this study, it is assumed that immaturity of the ET cartilage in infants, especially that of LL of the ET cartilage in CP infants, may be a significant risk factor for developing otitis media with effusion.
Radiation impedance of a finite circular piston on a viscoelastic half-space with application to medical diagnosis

In a recent study a new analytical solution was developed and validated experimentally for the problem of surface wave generation on a linear viscoelastic half-space by a rigid circular disk located on the surface and oscillating normal to it. The results of that study suggested that, for the low audible frequency range, some previously reported values of shear viscosity for soft biological tissues may be inaccurate. Those values were determined by matching radiation impedance measurements with theoretical calculations reported previously. In the current study, the sensitivity to shear viscoelastic material constants of theoretical solutions for radiation impedance and surface wave motion are compared. Theoretical solutions are also compared to experimental measurements and numerical results from finite-element analysis. It is found that, while prior theoretical solutions for radiation impedance are accurate, use of such measurements to estimate shear viscoelastic constants is not as precise as the use of surface wave measurements.
Purification, crystallization and preliminary X-ray diffraction analysis of pathogen-inducible oxygenase (PIOX) from Oryza sativa

Pathogen-inducible oxygenase (PIOX) is a heme-containing membrane-associated protein found in monocotyledon and dicotyledon plants that utilizes molecular oxygen to convert polyunsaturated fatty acids into their corresponding 2R-hydroperoxides. PIOX is a member of a larger family of fatty-acid α-dioxygenases that includes the mammalian cyclooxygenase enzymes cyclooxygenase 1 and 2 (COX-1 and COX-2). Single crystals of PIOX from rice (Oryza sativa) have been grown from MPD using recombinant protein expressed in Escherichia coli and subsequently extracted utilizing decyl maltoside as the solubilizing detergent. Crystals diffract to 3.0 A resolution using a rotating-anode generator and R-AXIS IV detector, and belong to space group P1. Based on the Matthews coefficient and self-rotation function analyses, there are presumed to be four molecules in the asymmetric unit related by noncrystallographic 222 symmetry.
Coefficients of Slip in Gases and the Law of Reflection of Molecules from the Surfaces of Solids and Liquids

First order correction term to Stokes Law of fall of droplets.—(1) Empirical. The experiments by which the value of the electronic charge was determined by the droplet method gave consistent results only when this law was modified by the factor (1+Al / a), where l / a is the ratio of mean free path to radius of droplet. (2) Hydrodynamic theory gives as a first approximation (1+ xi / a), where xi is the coefficient of slip. (3) Kinetic theory gives (1+0.7004l / a) in case all the molecules are diffusely reflected from the surface of the droplet, where l is defined by the relation eta =.3502 rho c-barl. If, however, the fraction reflected diffusely is f, the fraction (1-f) being specularly reflected, then the factor is [1+0.7004(2 / f-1)(l / a)]. The theory developed by Cunningham gave the numerical constant as 0.79, but this value is too high since experimental values of A nearly as low as 0.70 have actually been obtained. Coefficient of slip between gases and solids.—(1) Stokes' law method. Since xi =Al, xi may be computed directly from A. (2) Rotating cylinder method of determining viscosity is also capable of giving values of xi accurate to one per cent. If theta 0 is the limiting deflection for high pressures, and theta the deflection for a low pressure, then xi for that low pressure is ( theta 0- theta ) / K, where K is a geometrical constant of the apparatus. Values obtained by this method agree closely with those obtained by the first method. (3) Capillary effusion method. If the rate of flow of gas for unit pressure difference is T0 for high pressures and T for a low pressure, then xi for that low pressure is R(T-T0) / 4T0, where R is the radius. (4) Values of xi / l vary with the surface, for instance from 0.70 for air-mercury, and 0.87 for air-oil and air-glass, to 1.07 for air-fresh shellac. They also vary with the gas, for instance from 0.81 for hydrogen-oil and 0.82 for CO2-oil to 0.86 for air-oil, and 0.90 for helium-oil. Coefficient of diffuse reflection of gas molecules, determined from the relation A=(2 eta / rho c-bar)(2 / f-1) gives values of f which vary with the surface from 0.79 for air-fresh shellac and 0.89 for air-glass to 1.00 for air-mercury. The values also vary with the gas from 0.87 for helium-oil and 0.895 for air-oil to 0.92 for CO2-oil and hydrogen-oil. The values are for 23° C.
The poliovirus replication complex: Site for synthesis of poliovirus RNA☆

Abstract Pulse-labeled poliovirus RNA is found in the cytoplasm of HeLa cells in a structure which has been called the “poliovirus RNA replication complex”. The complex is bound to membranes but is released by treatment with deoxycholate. The replication complex sediments heterogeneously in a sucrose gradient with an average value of 250 s. It is unlikely that ribosomes are responsible for its fast rate of sedimentation because neither puromycin nor EDTA changes this rate. Furthermore, using cells in which the ribosomal RNA is highly radioactive, no association of ribosomes with the complex can be demonstrated. The viral RNA polymerase is found in association with the replication complex, and the in vitro synthesis of RNA occurs in the complex. Treatment of the complex with pronase or sodium dodecyl sulfate decreases the sedimentation rate of its RNA to 30 to 70 s. This suggests that protein is a major constituent of the complex; some or all of this protein must be the viral RNA polymerase. It also suggests that the sedimentation rate of the replicative intermediate may be faster than previously reported. The kinetics of incorporation of uridine into the complex and into finished chains of viral RNA are consistent with a precursor-product relation. These experiments are further evidence for the replicative intermediate as the site of viral RNA synthesis.
Psychosocial Needs of Rural Survivors of Cancer and Their Partners

It is important to understand the psychosocial needs of rural survivors of cancer to better serve this group. Survivors and partners filled out a pre-tested survey addressing general and mental health, quality of life and demographics. Twenty-nine survivors and 15 partners responded. Over 50% of both groups were at-risk for depression; 34% of the cancer survivors had some type of psychosocial problem requiring assistance. Areas to be targeted for psychosocial interventions for rural survivors include: management of side effects/complications of treatment; adjustment to changes in quality of life; emotional support; cancer impact on social relationships; uncertainty reduction.
Students' Understanding of Mathematical Objects in the Context of Transformational Geometry: Implications for Constructing and Understanding Proofs.

Abstract This research explored students’ views of geometric objects through the implementation of a curriculum module that allowed them to explore the relationships between transformational geometry and linear algebra. The majority of the students were middle and secondary mathematics education majors enrolled in a one-semester geometry course that is aimed at prospective teachers. A preponderance of the evidence suggests that the participating students, for the most part, viewed isometries operationally and viewed geometric objects (triangle, etc.) as “perceived.” Results also suggest that these two views influenced the students’ abilities to understand and to construct geometric proofs in transformational geometry.
Microcosms: Objects of Knowledge

MICROCOSMS is an on-going project, that will find its outcome in a set of physical exhibitions extending into the Internet. Our goal is to enlarge the discursive space of museums, universities, disciplines and collections by pushing at their conceptual boundaries. At the centre of the project lie the multifarious things of the world that we collect and analyse in the contemporary university. The knowledge produced from objects is integral to the primary mission of the university, and is quite distinct from textual knowledge. But while we would like to believe that sharp boundaries define the functions of knowledgeobjects, they in fact exist in a series of continua of motives and uses: temporal, spatial, institutional. For example, universities and museums are not distinct entities, and neither are museums, laboratories or libraries. Objects reside in teaching or research collections; in departmental or personal assemblages of memorabilia; in the limbo of closets and cabinets, temporarily obsolete and disposable, but never disposed. They are the sources of knowledge production, the storehouses of that knowledge, and the means of its dissemination. There is one space where all these aspects of objects may once have existed under the same roof and that is the 16th-century Curiosity Cabinet; there is one realm where they may be virtually reunited, and that is the Internet. These two spaces are the beginning and end of the project.
Effects of plant lectins on cation-activated brain ATPases.

Abstract The effects of concanavalin A (con A) and wheat germ agglutinin (WGA) on cation-activated ATPases in a crude homogenate of rat brain corpus striatum were examined. Con A enhanced the activity of Mg++-dependent-, and Ca++-activated-ATPases, and inhibited (Na+ + K+)- ATPase activity. WGA enhanced Mg++-dependent ATPase activity, but did not alter the activity of the other two components. The specificity of these interactions was demonstrated by reversal with specific lectin-interacting sugars. The possibility that these effects may be mediated by lectin-binding to physiologic regulatory sites, as well as the possible role of these interactions in the etiopathology of schizophrenia are discussed.
Inhibition of epileptiform activity by serotonin in rat CA1 neurons

Abstract This investigation was performed to determine the ability of serotonin in inhibiting bicuculline-induced epileptiform bursts in brain slices of male Sprague-Dawley rats. In all experiments, intracellular recording techniques were employed on CA1 neurons of the hippocampus. The neurons were stimulated either directly by the recording electrode or indirectly (synaptic stimulation) using a bipolar electrode placed on the CA2/CA3 region. Serotonin (20 μM) inhibited the directly evoked bursts of action potentials and caused a membrane hyperpolarization and decrease in membrane input resistance in untreated CA1 neurons. In the same experiments, serotonin inhibited the synaptically evoked action potential as well. Additionally, serotonin inhibited epileptiform bursts induced by single presynaptic stimuli in the presence of bicuculline. Moreover, in the concomitant presence of serotonin and bicuculline, there was a decrease in the number of spikes in bursts evoked by direct stimulation. Inhibition of epileptiform bursts was also achieved with the selective 5-HT1A agonist 8-hydroxydipropyl-amino-tetralin (8-OH-DPAT). The presence of the 5-HT3 antagonist MDL 72222 (30 μM), and the 5-HT2 antagonist ketanserin (3 μM) did not influence the ability of serotonin to inhibit epileptiform bursts. In the presence of bicuculline, the inhibitory action of serotonin, 8-OH-DPAT or the combination of serotonin, MDL 72222 and ketanserin, was accompanied by a membrane hyperpolarization and a decrease in membrane input resistance. To ascertain if serotonin can be applied on other models of epilepsy as well, we demonstrate the inhibition of epileptiform activity in the kainic acid treated brain slice preparation. These results suggest that serotonin, by activation of the 5-HT1A receptor subtype, may inhibit epileptiform activity in CA1 neurons of the rat brain slice preparation.
An exploration of a quasi-stable online network: A longitudinal perspective

This study uses social capital theory and social network analysis to explore how relations in an online academic communication network impact the overall structure of that network. Social network analysis is a particularly advantageous methodological tool for linking changes in microlevel choices to macrolevel structural alterations. Results indicate the online communication network's structure exists independent of changes in communication ties. Specifically degree centrality, betweenness centrality, and clique formation indicated communication ties are initiated and discontinued over a 7-month timeframe. However, the dynamic nature of the microlevel communication choices does not mirror the quasi-stable structure of the online network. Results provide avenues for future research.
The 2'-5' RNA Ligase of Escherichia coli: Purification, Cloning, and Genomic Disruption

An RNA ligase previously detected in extracts of Escherichia coli is capable of joining Saccharomyces cerevisiae tRNA splicing intermediates in the absence of ATP to form a 2′-5′ phosphodiester linkage (Greer, C., Javor, B., and Abelson, J. (1983) Cell 33, 899-906). This enzyme specifically ligates tRNA half-molecules containing nucleoside base modifications and shows a preference among different tRNA species. In order to investigate the function of this enzyme in RNA metabolism, the ligase was purified to homogeneity from E. coli lysate utilizing chromatographic techniques and separation of proteins by SDS-polyacrylamide gel electrophoresis. A single polypeptide of approximately 20 kilodaltons exhibited RNA ligase activity. The amino terminus of this protein was sequenced, and the open reading frame (ORF) encoding it was identified by a data base search. This ORF, which encodes a novel protein with a predicted molecular mass of 19.9 kDa, was amplified from E. coli genomic DNA and cloned. ORFs coding for highly similar proteins were detected in Methanococcus jannaschii and Bacillus stearothermophilus. The chromosomal gene encoding RNA ligase in E. coli was disrupted, abolishing ligase activity in cell lysates. Cells lacking ligase activity grew normally under laboratory conditions. However, moderate overexpression of the ligase protein led to slower growth rates and a temperature-sensitive phenotype in both wild-type and RNA ligase knockout strains. The RNA ligase reaction was studied in vitro using purified enzyme and was found to be reversible, indicating that this enzyme may perform cleavage or ligation in vivo.
Striving for consistency in a national assessment: the challenges of applying a reference-condition approach at a continental scale

One of the biggest challenges when conducting a continental-scale assessment of streams is setting appropriate expectations for the assessed sites. The challenge occurs for 2 reasons: 1) tremendous natural environmental heterogeneity exists within a continental landscape and 2) reference sites vary in quality both across and within major regions of the continent. We describe the process used to set expectations for the multimetric index of biotic integrity (MIBI) and observed/expected (O/E) indices generated from predictive models used to assess stream condition for the US Wadeable Streams Assessment (WSA). The assessment was based on a reference-site approach, in which the least-disturbed sites in each region of the US were used to establish benchmarks for assessing the condition of macroinvertebrate assemblages at other sites. Reference sites were compiled by filtering WSA sample sites for disturbance using a series of abiotic variables. Additional reference sites were needed and were obtained from other state, university, and federal monitoring programs. This pool of potential reference sites was then assessed for uniformity in site quality and comparability of macroinvertebrate sample data. Ultimately, 1625 sites were used to set reference expectations for the WSA. Reference-site data were used to help define 9 large ecoregions that minimized the naturally occurring variation in macroinvertebrate assemblages associated with continental-wide differences in biogeography. These ecoregions were used as a basis for developing MIBI and O/E indices and for reporting results. A least-disturbed definition of reference condition was used nationally, but we suspect that the quality of the best extant sites in ecoregions, such as the Northern Plains and Temperate Plains, was lower than that of sites in other ecoregions. For the MIBI assessment, we used a simple modeling approach to adjust scores in ecoregions where gradients in reference-site quality could be demonstrated conclusively. The WSA provided an unparalleled opportunity to push the limits of our conceptual and technical understanding of how to best apply a reference-condition approach to a real-world need. Our hope is that we have learned enough from this exercise to improve the technical quality of the next round of national assessments.
Integral-equation-based analysis of transient scattering and radiation from conducting bodies at very low frequencies

An implicit marching-on-in-time (MOT) algorithm for solving a time domain electric field integral equation pertinent to the analysis of transient scattering and radiation from perfect electrically conducting bodies that are excited by very low frequency signals is presented. Spatial variations in electric current densities are described by loop-tree basis functions to ensure stability of the time marching scheme when geometric discretisation lengths are much smaller than a light time step. Such basis functions were previously employed within explicit MOT solvers. However, to our knowledge, this is the first study to demonstrate their usefulness in tackling time domain integral equation low-frequency breakdown and related stability problems. This is achieved by deploying loop-tree basis functions within an implicit MOT scheme. Numerical examples that demonstrate the proposed scheme's effectiveness in analysing electromagnetically small or mixed scale structures and its ability to operate with time steps determined by the Nyquist criterion as opposed to geometric discretisation rules are presented.
Function and survival of renal allografts from the same donor transplanted into kidney-only or kidney-pancreas recipients.

BACKGROUND The aim of this study was to assess whether kidney-pancreas transplantation (KPT) compromises the prognosis of kidney transplantation (KT). METHODS This study included 368 paired recipients who received grafts from the same donor (184 KPT/184 KT), i.e., renal grafts with the same pretransplant functional and pathologic characteristics. RESULTS KPT recipients (KPR) were significantly younger and included fewer African-Americans (22% vs. 6%, P=0.0005) than recipients of kidney alone (KR). During year 1 after transplant surgery, KPR were re-admitted more often than KR (4.2+/-2 vs. 2.8+/-2, P < 0.0001). The number of acute rejections (AR) and the serum creatinine were not significantly different in KR and KPR up to 3 years after transplant. After 44+/-29 months, 13% of KR and 17% of KPR died (NS), and 17% of KR and 16% of KPR lost their kidneys (NS). In KPR, reduced renal graft survival did not correlate with AR (P=0.44), but it correlated with: older donors, younger recipients, elevated serum creatinine at 6 months, pancreas loss, and the number of episodes of acute graft dysfunction evaluated by biopsy (multivariate analysis). By Cox, graft and patient survival were not significantly different in KR and KPR. However, the patient survival of KPR < 40 years of age was lower than that of KR (P=0.02). Renal biopsies (n=165) in 40 paired recipients showed no significant differences in AR, interstitial fibrosis, or vascular pathology. CONCLUSIONS Renal graft function, structure, and survival are not different in KPR and KR, but the correlates of renal graft survival are different in these two groups of recipients.
Local Cerebral Blood Flow during Lidocaine-induced Seizures in Rats

Neurophysiologic and local cerebral metabolic mapping techniques indicate that seizures associated with lidocaine toxicity originate in subcortical brain structures. Normally local cerebral blood flow (l-CBF) is quantitatively coupled to local cerebral metabolic rate for glucose (l-CMRg). In the present study the response of l-CBF to a lidocaine-induced preconvulsive state (localized seizure activity in the absence of a grand mal seizure) was evaluated in rats anesthetized with 60% nitrous oxide. Lidocaine administered as a bolus (20 mg/kg) followed by an infusion (4 mg/kg) over 5.5 min resulted in progressive alteration in the electroencephalogram (EEG). L-CBF was studied with the 14C-iodoantipyrine autographic method when the preconvulsive EEG pattern consisted of a repetitive spike and wave complex at a frequency of 14 +/- 1 X min-1 complexes, superimposed on practically isoelectric background activity. Under these conditions high doses of lidocaine significantly (P less than 0.05) decreased (range -30% to -68%) l-CBF in 71% of the 34 brain regions studied. The greatest exception to this trend for l-CBF to decrease was observed in the limbic system wherein l-CBF remained within control ranges in eight of the 11 structures evaluated. Qualitative comparison of lidocaine l-CBF changes with l-CMRg changes obtained under similar conditions indicated a general trend for local flow and metabolism to decrease in parallel. Exceptions to this were confined to certain limbic areas (amygdala and hippocampus) in which increases in l-CMRg were more than 100% greater than slight (P greater than 0.05) increases in l-CBF.(ABSTRACT TRUNCATED AT 250 WORDS)
Collaborations for Change: Who is Playing and Who is Winning in Community-Based Organization Led Development in Rural Appalachia

My involvement in this research began in 1996 as an assistant professor of sociology at West Virginia University Institute of Technology (WVUIT). There I worked with the Southern Appalachian Labor School (SALS) attending board meetings, evaluating programs, and operating a service learning program. What emerged from this work is a community development model showing the strenghts and difficulties of integrating multiple resources and groups to help facilitate grassroots development. The paper discusses SALSs'role in addressing basic needs, fostering indigenous leadership, faciliating service learning programs, and increasing local participation in development policy including generating networks needed to transform those involved and assist rural communities in the modern economy
Unsymmetric and Biaxial Bending of FRP Angle Sections

This article presents a procedure for estimating the cracking moment of a fiber reinforced plastic (FRP) angle section subjected to unsymmetrical or biaxial bending. The procedure is demonstrated by means of numerical examples for both equal and unequal-leg angle sections subjected to bending about non-principal axes of the cross section.