cssi/SciSciGPT-SciSciNet huggingface dataset:
Steroidal control of rat uterine 17β-hydroxysteroid dehydrogenase activity

Abstract The interconversion of estradiol-17β and estrone in the rat uterus is due to the action of 17β-hydroxysteroid dehydrogenase. Whole uteri or 800 × g supernatant fractions of the uteri were incubated in the presence of [3H] estradiol-17β and NAD at 37°C for 3 h or 1 h, respectively. In the mature rat uterus the oxidation of estradiol-17β and estrone was dependent on the stage of the estrous cycle, suggesting hormonal control. The 17β-hydroxysteroid dehydrogenase activity was highest at estrus (200 fmol estrone) and lowest at diestrus (80 fmol estrone). An enhancement of activity occurred when adult rats at each stage of the estrous cycle were administered estradiol-17β, while progesterone administration at each stage resulted in decreased enzyme activity. The uterine 17β-hydroxysteroid dehydrogenase activity of estradiol-17β treated ovariectomized rats was time and dose dependent but decreased when progesterone was administered with or without estradiol-17β administration. These results suggest that estradiol-17β caused an increase in enzyme activity that was inhibitable by progesterone in the rat uterus. The increased 17β -hydroxysteroid dehydrogenase activity may reflect a specific response of the rat uterus to estradiol-17β.
Test of the H + 2 + He interaction potential. Comparison of the interactions of He with H + , H + 2 and H + 3

Abstract Gaseous ion mobility data are used to test theoretical potentials for H+2 + He at large separation distances. Agreement with ab initio calculations is good, but significant discrepancy with recent diatomics-in-molecules calculations is found. Mobility data are also used to calculate the spherically-averaged H+3 + He potential, which is compared with H+2 + He and an ab initio H+ + He calculation.
Investigation of IL-6 and IL-10 signalling via mathematical modelling

Steatosis, i.e., the accumulation of fat in hepatocytes, plays an important role in the progression of non-alcoholic fatty liver disease (NAFLD). It has been shown that STAT3 activation is involved in a decrease of lipid accumulation while C/EBPβ is correlated with an increase of fat content and steatosis. It is known that STAT3 and C/EBPβ are activated by IL-6 and that IL-6 signalling is also affected by IL-10, even though the exact mechanism is unclear. This paper develops a model for IL-6 and IL-10 signal transduction and then investigates the effect that stimulation with these cytokines has on the transcription factor dynamics. In an initial step, some parameters of a previously developed IL-6 signalling model are re-estimated based upon newly developed experimental data for the Jak-STAT pathway. Furthermore, the Erk-C/EBPβ pathway model is extended to also include the activated transcription factor C/EBPβ in the nucleus. Since IL-10 signals through the Jak-STAT but not the Erk-C/EBPβ pathway, a model was developed which includes interaction between IL-6 and IL-10 signalling as both mechanisms share signal transduction through the Jak-STAT pathway. Based upon the model, the activity ratio of Jak-STAT and Erk-C/EBPβ was investigated for different stimulation levels of IL-6 and IL-10.
The Synthesis and Biological Activity of 1-(2-Deoxy-4-Thio-α;-L-Threo-Pentofuranosyl)Thymine

Abstract The procedure of Huang and Hui (Nucleosides & Nucleotide 1993, 12, 139-147) was found to give benzyl 3,5-di-O-benzyl-2-deoxy-1,4-dithio-α-L-threo-pentofuranoside (6) rather than the claimed D-erythro isomer. This sugar was converted to an anomeric mixture of the thymine nucleosides. The mixture was separated and the α-anomer (α-10) was found to be cytotoxic, whereas theβ-anomer (β-10) was inactive.
Decreased Interfacial Charge Recombination Rate Constants with N3-Type Sensitizers

Interfacial charge separation and recombination were quantified at sensitized mesoporous nanocrystalline TiO2 interfaces immersed in acetonitrile electrolyte. Two sensitizers contained a phenylenethynylene spacer between a cis-Ru(NCS)2 core and TiO2 anchoring groups, and a third sensitizer did not contain the spacer, cis-Ru(dcb)(bpy)(NCS)2, where bpy is 2,2′-bipyridine and dcb is 4,4′-(CO2H)2-bpy. Excited-state injection occurred with approximately the same yield for all these sensitizers and was rapid with kinj > 108 s−1. Representative charge recombination rate constants from nanosecond transient absorption data were quantified by a distribution analysis, based on the Kohlrausch−Williams−Watts model, and were found to be 3 times slower for the sensitizers with the phenylenethynylene spacer. Slow recombination kinetics manifested itself as an increased open circuit photovoltage, Voc. The Voc values measured experimentally were contrasted with calculated values abstracted from the diode equation with idea...
Poisson and Multinomial Mixture Models for Multivariate SIMS Image Segmentation

Multivariate statistical methods have been advocated for analysis of spectral images, such as those obtained with imaging time-of-flight secondary ion mass spectrometry (TOF-SIMS). TOF-SIMS images using total secondary ion counts or secondary ion counts at individual masses often fail to reveal all salient chemical patterns on the surface. Multivariate methods simultaneously analyze peak intensities at all masses. We propose multivariate methods based on Poisson and multinomial mixture models to segment SIMS images into chemically homogeneous regions. The Poisson mixture model is derived from the assumption that secondary ion counts at any mass in a chemically homogeneous region vary according to the Poisson distribution. The multinomial model is derived as a standardized Poisson mixture model, which is analogous to standardizing the data by dividing by total secondary ion counts. The methods are adapted for contextual image segmentation, allowing for spatial correlation of neighboring pixels. The methods are applied to 52 mass units of a SIMS image with known chemical components. The spectral profile and relative prevalence for each chemical phase are obtained from estimates of model parameters.
Interdigitating muscle fibers throughout orbicularis oris inferior: preliminary observations.

Observations of serial sections from two cadaveric specimens of human lower lip are presented. The complex structure of the muscles of the lower lip region includes several fascicles of fibers that...
Nitric Oxide–GAPDH–Siah: A Novel Cell Death Cascade

1. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an extremely abundant glycolytic enzyme, and exemplifies the class of proteins with multiple, seemingly unrelated functions. Recent studies indicate that it is a major intracellular messenger mediating apoptotic cell death. This paper reviews the GAPDH cell death cascade and discusses its clinical relevance. 2. A wide range of apoptotic stimuli activate NO formation, which S-nitrosylates GAPDH. The S-nitrosylation abolishes catalytic activity and confers upon GAPDH the ability to bind to Siah, an E3-ubiquitin-ligase, which translocates GAPDH to the nucleus. In the nucleus, GAPDH stabilizes the rapidly turning over Siah, enabling it to degrade selected target proteins and affect apoptosis. 3. The cytotoxicity of mutant Huntingtin (mHtt) requires nuclear translocation which appears to be mediated via a ternary complex of GAPDH-Siah-mHtt. The neuroprotective actions of the monoamine oxidase inhibitor R-(-)-deprenyl (deprenyl) reflect blockade of GAPDH-Siah binding. Thus, novel cytoprotective therapies may emerge from agents that prevent GAPDH-Siah binding.
The Vitamin-B12 Activity of Mullet and Shark Serum

Microbiological assay procedures using Euglena gracilis, x strain, were employed to measure the vitamin-B12 activity of samples of mullet, shark, and human sera. The average activity was 10.7, 0.84, and 1.15 mpg/ml, respectively. The relatively higher activity of mullet sera compared to shark sera may reflect significant physiological differences between these subclasses of fish and possibly different feeding habits. Bacteria isolated from mullet intestinal contents were grown in a vitamin Bla-deficient medium. Of 8 cultures tested, 6 had vitamin-B12 activity when assayed with Escherichia coli 113-3 and 1 had activity for Euglena. dues were assayed. In other expcrimcnts concentrates of cell resiTwo out of 4 supposedly negative vitamin-1312 producers had activity for Euglena.
Effects of ischemia on the function and structure of the cat carotid body.

Abstract Interrupting the blood supply to the carotid body by ligating arteries of its vascular peduncle altered the chemoreceptive properties of the carotid nerve and produced structural changes in parenchymal (glomus and sustentacular) cells. The onset of ischemia was marked by an increase in the discharge of both A (myelinated) and C (unmyelinated) sensory fibers followed by depression and finally by receptor silence. The discharge of A-fibers disappeared after 30–50 min and that of C-fibers after 60–90 min. During ischemia of 15–60 min duration the threshold to pharmacological (NaCN, ACh) and ‘natural’ (hypoxic) stimuli progressively increased and was accompanied by reversible changes in the structure of parenchymal cells and nerve endings. Ischemia for 2 h or longer produced irreversible functional damage and disappearance of glomus and sustentacular cells from the carotid body. Following ischemic injury, nerve fibers regenerated and all responded to mechanical stimuli but only a few were stimulated by natural or pharmacological agents. Thus, parenchymal cells of the carotid body appear to be most important in transduction by allowing sensory fibers to respond to chemical stimuli.
Higher order approximations for tandem queueing networks

In this paper a higher order approximation for single server queues and tandem queueing networks is proposed and studied. Different from the most popular two-moment based approximations in the literature, the higher order approximation uses the higher moments of the interarrival and service distributions in evaluating the performance measures for queueing networks. It is built upon the MacLaurin series analysis, a method that is recently developed to analyze single-node queues, along with the idea of decomposition using higher orders of the moments matched to a distribution. The approximation is computationally flexible in that it can use as many moments of the interarrival and service distributions as desired and produce the corresponding moments for the waiting and interdeparture times. Therefore it can also be used to study several interesting issues that arise in the study of queueing network approximations, such as the effects of higher moments and correlations. Numerical results for single server queues and tandem queueing networks show that this approximation is better than the two-moment based approximations in most cases.
Tropomyosin B from the African civet, Civettictis civetta

Abstract 1. 1. Tropomyosin B has been prepared from the muscle tissue of an African civet, Civettictis civetta . 2. 2. From the amino acid composition, optical rotatory dispersion and sedimentation coefficient, the tropomyosin B isolated from the African civet appears to be very similar to rabbit tropomyosin.
Development of Communitarian Regulation in the Chemical Industry

This study explores the development of communitarian regulation in the American chemical industry by focusing on the history and challenges facing Responsible Care, the leading example of regulation by an industry association on the environmental scene today.
Genetic architecture of the circadian clock and flowering time in Brassica rapa

The circadian clock serves to coordinate physiology and behavior with the diurnal cycles derived from the daily rotation of the earth. In plants, circadian rhythms contribute to growth and yield and, hence, to both agricultural productivity and evolutionary fitness. Arabidopsis thaliana has served as a tractable model species in which to dissect clock mechanism and function, but it now becomes important to define the extent to which the Arabidopsis model can be extrapolated to other species, including crops. Accordingly, we have extended our studies to the close Arabidopsis relative and crop species, Brassica rapa. We have investigated natural variation in circadian function and flowering time among multiple B. rapa collections. There is wide variation in clock function, based on a robust rhythm in cotyledon movement, within a collection of B. rapa accessions, wild populations and recombinant inbred lines (RILs) derived from a cross between parents from two distinct subspecies, a rapid cycling Chinese cabbage (ssp. pekinensis) and a Yellow Sarson oilseed (ssp. trilocularis). We further analyzed the RILs to identify the quantitative trait loci (QTL) responsible for this natural variation in clock period and temperature compensation, as well as for flowering time under different temperature and day length settings. Most clock and flowering-time QTL mapped to overlapping chromosomal loci. We have exploited micro-synteny between the Arabidopsis and B. rapa genomes to identify candidate genes for these QTL.
Reduction of porcine parvovirus infectivity in the presence of protecting osmolytes

Osmolytes are natural compounds found in the cells of many organisms that stabilize intracellular proteins against environmental stresses. Protecting osmolytes can promote protein folding, whereas denaturing osmolytes have the opposite effect. A variety of osmolytes were tested for their antiviral activity against porcine parvovirus (PPV). PPV is a non-enveloped, icosahedral, single-strand DNA virus. We have discovered two protecting osmolytes, trimethylamine N-oxide (TMAO) and glycine that reduce the infectivity of PPV by four logs (99.99%). We hypothesize that both osmolytes stabilize viral capsid proteins and prevent them from assembling into viable virus particles. The advantage of the antiviral compounds found is that they can be applied post-infection, which increases their potential to serve as a therapeutic drug.
Nucleon-Nucleus Scattering and the Choice between Sets of Nucleon-Nucleon Phase Shifts

Nucleon-nucleon (N-N) phase shifts may be inferred from N-nucleus scattering polarization data. For trial sets of N-N phase shifts, the scattering polarization is calculated in the first Born approximation and compared with experimental data. It is shown that multiple scattering effects change the Born approximations. Choices between various sets of N-N phase shifts are thus rendered unreliable by these multiple scattering effects. (T.F.H.)
Origins of the recent US—EC agricultural trade dispute

Enlargement of the European Community (EC), recent reforms of the Common Agricultural Policy (CAP), and structural policy changes in the Community have generated economic conditions whose combined long-term effect will be a decrease in the demand for US agricultural exports to the EC. Factors such as the imposition of quotas for milk production and the integration of Spanish and Portuguese agricultural policies into the CAP and its Community preference principle have aggravated an apparent shift in demand for US farm exports. Consequently, these changes have contributed to the heated dispute over the future of US–EC agricultural trade.
Finite dimensional lie-poisson approximations to vlasov-poisson equations†

Many of the basic equations of conservative continuum mechanics (Euler, Vlasov-Poisson, Vlasov-Maxwell, MHD, etc.) are Hamiltonian systems with respect to Lie-Poisson brackets on dual spaces of infinite dimensional Lie algebras. The development of Lie-Poisson integrators for finite dimensional Lie-Poisson systems has shown that they are superior in the numerical simulations of these systems, especially with regard to long term phenomena. This paper shows how to truncate one of these systems, the Vlasov-Poisson equation of plasma physics, to a finite dimensional Lie-Poisson system. This requires replacing the functions on single-particle phase space, with their Poisson bracket Lie algebra structure, by a finite dimensional Lie algebra. Replacing the densities by their moments of order up to k about a fixed reference point corresponds to replacing the functions by their Taylor expansions up to order k. Unfortunately, these truncated Taylor expansions do not form a Lie algebra, since the functions which vanish through order k do not form an ideal under Poisson bracket. Geometrically, this corresponds to the fact that canonical transformations which fix the reference point do not form a normal subgroup. Introducing the location of a reference point in phase space as an extra variable and truncating with respect to this moving point turns out to decouple the “location” from “shape” coordinates of a lump of density in phase space, as far as the Poisson bracket is concerned. One can then replace the shape coordinates by a finite number of moments. The central result of the paper is a construction of the decoupling map described above in the general context of the decomposition of a Lie group as a product of subgroups. The main theorem is first proved by the general theory of Poisson reduction, then by explicit calculation, and lastly by showing that the Poisson isomorphism follows from the lift of a natural groupoid isomorphism. The groupoid aspect of the theory also provides natural Poisson maps, useful in the application of Ruth-type integration techniques, which do not seem easily derivable from the general theory of Poisson reduction. © 1994 John Wiley & Sons, Inc.
Endovascular management of symptomatic spasm of radial artery bypass graft: technical case report.

OBJECTIVE: To describe the technique of endovascular access for treatment of vasospasm of a radial artery bypass graft from the occipital artery to the M3 branch of the middle cerebral artery (MCA) in a patient with moyamoya disease. CLINICAL PRESENTATION: A 32-year-old woman presented with recurrent right-sided ischemic symptoms in the territory of a previous stroke. Angiographic findings were consistent with moyamoya disease, and a perfusion deficit was identified on computed tomography (CT) perfusion imaging. TECHNIQUE: The patient underwent a left MCA bypass graft for flow augmentation. She returned with an occluded bypass graft, collateralization of the anterior MCA territory through a spontaneous synangiosis, and a severe perfusion deficit in the posterior MCA territory. She underwent a revision bypass graft procedure with the radial artery from the occipital artery stump to the MCA-M3 branch. She developed repeated symptomatic vasospasm of the radial artery graft postoperatively. After systemic anticoagulation, the graft was accessed through the occipital artery, and intra-arterial verapamil was injected. When this failed to resolve the graft spasm, the radial artery graft was accessed with a 0.14-inch Synchro-2 microwire (Boston Scientific, Natick Massachusetts), and sequential angioplasties were performed using over-the-wire balloons from the proximal to distal anastomosis and in the occipital artery stump. A nitroglycerin patch was applied cutaneously over the graft to relieve the vasospasm. RESULTS: No complications occurred. Graft patency with robust flow was observed on the 5-month follow-up angiogram. CONCLUSION: Endovascular techniques can be safely used for salvage of spastic extracranial-intracranial grafts.
Transdisciplinarity and Translation: Preparing Social Work Doctoral Students for High Impact Research

Contemporary research models are becoming increasingly transdisciplinary (TD), multilevel, community-connected, and bent on expediting the movement of research to impact. This requires not only fre...
An update on bicalutamide in the treatment of prostate cancer.

In this update, bicalutamide (Casodex™, Zeneca Pharmaceuticals) has been confirmed as an effective, well-tolerated and convenient non-steroidal anti-androgen for advanced prostate cancer. Preclinical and clinical studies have indicated its potential as monotherapy, with quality of life advantages compared with castration. A head-to-head comparison with flutamide, where both anti-androgens were used as part of combined androgen blockade, has suggested that the choice of components in this regimen can influence outcome, and has demonstrated that bicalutamide is better tolerated than flutamide. There is also preliminary evidence to support the potential use of bicalutamide in treatment of early-stage disease and tumours that are refractory to other non-steroidal anti-androgens.
River discharge controls phytoplankton dynamics in the northern San Francisco Bay estuary

Phytoplankton dynamics in the upper reach of the northern San Francisco Bay estuary are usually characterized by low biomass dominated by microflagellates or freshwater diatoms in winter, and high biomass dominated by neritic diatoms in summer. During two successive years of very low river discharge (the drought of 1976-77), the summer diatom bloom was absent. This is consistent with the hypothesis that formation of the diatom population maximum is a consequence of the same physical mechanisms that create local maxima of suspended sediments in partially-mixed estuaries: density-selective retention of particles within an estuarine circulation cell. Because the estuary is turbid, calculated phytoplankton growth rates are small in the central deep channel but are relatively large in lateral shallow embayments where light limination is less severe. When river discharge falls within a critical range (100–350 m3 s−1) that positions the suspended particulate maximum adjacent to the productive shallow bays, the population of neritic diatoms increases. However, during periods of high discharge (winter) or during periods of very low discharge (drought), the suspended particulate maximum is less well-defined and is uncoupled (positioned downstream or upstream) from the shallow bays of the upper estuary, and the population of neritic diatoms declines. Hence, the biomass and community composition of phytoplankton in this estuary are controlled by river discharge.
The role of color doppler and staging biopsies in prostate cancer detection

Abstract Objectives To review the current published data on the role of color Doppler sonography and sonographically-guided staging biopsies in the detection and staging of prostate cancer. This article also discusses the role of color Doppler sonography in defining the ideal patients for neoadjuvant chemotherapy. Methods Peer-reviewed reports in the radiologic, urologic, and medical literature were reviewed. Data from our own institution served as illustrative material. Results Color Doppler sonography using state of the art ultrasound equipment produced from the mid 1990s onward can define areas of hypervascularity in the prostate. When located in the peripheral zone and associated with definable lesions, these areas likely represent carcinoma. More importantly, when isoechoic areas contain hypervascular foci with chaotic flow, cancer is also likely. In 93% of sites that contain normal vascularity, prostate cancer was not detected by biopsy. Staging biopsies are not frequently performed in current clinical practice. A positive seminal vesicle biopsy is associated with capsular penetration in 100% and positive lymph nodes in 50% of patients with prostate cancer. Conclusions Color Doppler sonography and staging biopsies may have a more significant role as newer alternative therapies for prostate cancer become popular. These two techniques show promise for increasing the accuracy of pretreatment staging over current algorithms, which are less than adequate.
Central ideas of Buckingham (1907), A century later

A century ago, Edgar Buckingham presented data and a theoretical conceptualization of soil moisture movement. His work constitutes a milestone in the history of soil physics and more generally, of movement of multiple fluid phases in porous media. Starting from first principles, Buckingham formulated a conceptual model to make rational sense of long-term observations of evaporation from soil columns. Central to his model were the notion of a capillary potential, soil moisture retention curve, and potential-dependent hydraulic conductivity. Buckingham recognized that whereas heat capacity and thermal conductivity were independent of temperature in Fourier9s heat equation, in the case of soil moisture, the slope of the soil-moisture retention curve (analogous to specific heat) and capillary conductivity were both strong functions of capillary potential. Noting that available solutions of Fourier9s linear differential equation did not apply to moisture movement in soils, Buckingham was skeptical that the nonlinear problem could be solved mathematically. This is perhaps why he did not present a partial differential equation for soil-moisture movement. Such an equation would be gvien in 1931 by Richards. Despite considerable efforts, analytical solutions to Richards9 equation can be obtained only under simplifying assumptions. While these solutions give valuable insights into patterns of soil moisture movement, they cannot adequately address problems of the natural soil environment. Although Buckingham9s model remains the only workable physical-mathematical conceptualization for studying moisture movement in soils, his own skepticism of its ability to reliably describe moisture movement in soils is still valid. More profound, his skepticism captures the limitations inherent in precisely describing the behavior of earth systems. This paper examines Buckingham9s central ideas in light of developments in groundwater hydrology and soil mechanics and reflects on the limits of our ability to quantitatively understand moisture movement in unsaturated soils.
Heuristically derived tumor burden score as a prognostic factor for stage IIIB carcinoma of the cervix

Abstract Purpose: A retrospective of radiotherapeutic management of locally advanced carcinoma of the uterine cervix was performed to evaluate the effect of various treatment parameters and disease extent upon treat outcome. Methods and Materials: Between 1976 and 1989, 89 patients with Stage IIIB disease were treated with external beam radiotherapy and brachytherapy. Treatment outcomes were evaluated by dose to Point A, the proportion of Point A dose delivered by brachytherapy, clinical response at 3 months, and a newly developed tumor burden scoring system that quantifies the anatomical extent of disease. Kaplan—Meier estimates of tumor control and survival parameters were determined. Results: Loco-regional control (LRC), disease-free survival (DFS), and overall survival (OVS) at 5 years were 52.9%, 45.5%, and 50.3%, respectively. Clinical response at 3 months was highly predictive of local and distant tumor control. There was no correlation between proportion of brachytherapy dose and treatment outcome. The tumor burden scoring system demonstrates that FIGO Stage IIIB disease can be clinically divided into two prognostic groups of low and high tumor burden. Five year LRC was 62.9% and 40.2% for the low and high tumor burden groups, respectively ( p = 0.024). Within the high tumor burden group the LRC was 53.0% and 22.5% when the point A dose given was > 78 Gy and ≤ 78 Gy, respectively ( p = 0.047). This correlated with improved DFS and OVS. Conclusion: The tumor burden scoring system subdivides FIGO Stage IIIB cervical carcinoma into two prognostic groups, predicting for overall survival and demonstrating a dose response in the high tumor burden group. This system may serve to improve future comparison of treatment outcome and to guide selection of patients who may benefit from a more aggressive treatment approach.
A soft table for the natural frequencies and modal parameters of uniform circular plates with elastic edge support

Abstract The paper introduces a “soft table” for the natural frequencies and modal parameters of uniform circular plates with elastic edge support. In contrast to conventional tabulations on paper, the “soft table” allows to save space and display parameters for required number of vibration modes. The “soft table” is realized in a collection of Matlab® codes that calculate natural frequencies and mode shape parameters for a given set of translational and rotational constraints and modifiable Poisson ratio. Calculations of natural frequencies and modal parameters for a wide range of constraints revealed distinctive regions where the frequencies and parameters could change considerably. Knowing position and extension of these regions could be essential for design and vibration control of structures incorporating circular plates.
Biochemical Basis for Depigmentation of Skin by Phenolic Germicides

Occupational exposure to germicides containing various phenols produces depigmentation of human skin. The chemical basis for this depigmentation may be competitive inhibition of the enzyme tyrosinase. In the tyrosinase reaction tyrosine has K m of 2.2 × 10 -3 M: p-tert -butylphenol has a K 1 of 1.95 × 10 -4 M. In the oxidase reaction, the estimated K 1 for p-tert -butylphenol is 2.02 × 10 -4 M. It is recommended that chemicals to be included in products that will come into close contact with human skin should be tested for their ability to inhibit tyrosinase.
Cerebral activation, hostility, and cardiovascular control during mental stress.

Objective: Hostility has been established as a risk factor for the development of coronary artery disease. Putatively pathogenic hemodynamic and neuroendocrine responses to psychological stressors are associated with hostility, but the cerebral effects of hostility and their relationship to these responses are unknown. This pilot study examined cardiovascular and cerebral blood flow responses to stress in subjects with high and low levels of trait hostility. Methods: Regional cerebral blood flow was measured by single-photon emission computed tomography (SPECT) during a control condition and in response to mental arithmetic stress. Results: The stressor was associated with reduced blood flow to the prefrontal cortex, and this reduction was greater in the high hostility subjects. Conclusion: These preliminary findings support the hypothesis that mental arithmetic stress is associated with reduced blood flow to prefrontal cortex, and that trait hostility is associated with a stronger effect.
A Sensitive Analysis for Nitrosamines

Abstract A number of nitrosamines have been reduced to hydrazines and condensed with 9-anthraldehyde and 9-phenanthraldehyde to give highly fluorescent hydrazones which can be separated by thin layer chromatography and identified using Rf, ultroviolet and mass spectra.
The paucity of minimal change disease in adolescents with primary nephrotic syndrome

Data are sparse regarding the histological lesions associated with the primary nephrotic syndrome in adolescents. To our knowledge there are only two published articles that have specifically addressed the histopathological lesions that typify idiopathic nephrotic syndrome in the adolescent population. We reviewed our experience from the last 14 years of children between the ages of 12 and 18 years who were referred to our center for the evaluation of the nephrotic syndrome. A total of 29 adolescents met the inclusion criteria for this review. All patients were biopsied prior to the initiation of treatment. The sex ratio consisted of 52% males and 48% females and the racial breakdown was largely African-American, with 83% black adolescents, 7% Hispanic, and 10% Caucasian patients. Minimal change nephrotic syndrome (MCNS), the predominant lesion of children at an early age, was noted in only 20% of patients. The majority of patients (55.2%) had focal segmental glomerulosclerosis (FSGS); 7% had IgM nephropathy and 3.5% had diffuse mesangial hypercellularity. Only 7% of biopsied adolescents had membranoproliferative glomerulonephritis. Our results indicate that the most common lesion in this predominantly African-American patient population is FSGS, with only a small number showing MCNS. Thus, in our experience derived from a racially mixed population, adolescents with the nephrotic syndrome are less likely to have MCNS than younger children.
Total and methyl mercury in whole blood measured for the first time in the U.S. population: NHANES 2011–2012

Abstract Background Despite the public health and toxicologic interest in methyl mercury (MeHg) and ethyl mercury (EHg), these mercury species have been technically difficult to measure in large population studies. Methods Using NHANES 2011–2012 data, we calculated reference ranges and examined demographic factors associated with specific mercury species concentrations and the ratio of MeHg to THg. We conducted several multiple regression analyses to examine factors associated with MeHg concentrations and also with the ratio of MeHg to THg. Results Asians had the highest geometric mean concentrations for MeHg, 1.58 µg/L (95% CI 1.29, 1.93) and THg, 1.86 µg/L (1.58, 2.19), followed by non-Hispanic blacks with MeHg, 0.52 µg/L (0.39, 0.68) and THg, 0.68 µg/L (0.54, 0.85). Greater education attainment in adults and male sex were associated with higher MeHg and THg concentrations. Race/ethnicity, age, and sex were significant predictors of MeHg concentrations, which increased with age and were highest in Asians in all age categories, followed by non-Hispanic blacks. Mexican Americans had the lowest adjusted MeHg concentrations. The ratio of MeHg to THg was highest in Asians, varied by racial/ethnic group, and increased with age in a non-linear fashion. The amount of increase in the MeHg to THg ratio with age depended on the initial ratio, with a greater increase as age increased. Of the overall population, 3.05% (95% CI 1.77, 4.87) had MeHg concentrations >5.8 µg/L (a value that corresponds to the U.S. EPA reference dose). The prevalence was highest in Asians at 15.85% (95% CI 11.85, 20.56), increased with age, reaching a maximum of 9.26% (3.03, 20.42) at ages 60–69 years. Females 16–44 years old had a 1.76% (0.82–3.28) prevalence of MeHg concentrations >5.8 µg/L. Conclusions Asians, males, older individuals, and adults with greater educational attainment had higher MeHg concentrations. The ratio of MeHg to THg varied with racial/ethnic group, increased with age, and was nonlinear. U.S. population reference values for MeHg and the ratio of MeHg to THg can assist in more precise assessment of public health risk from MeHg consumed in seafood.
Social cognitions associated with pubertal development in a sample of urban, low-income, African-American and Latina girls and mothers.

Abstract Purpose: To assess girls' acquisition of new sex-related social cognitions at puberty and the social meanings they attribute to changes in their primary social relationships. Methods: As part of a larger study assessing sociosexual cognitions of urban girls, 57 African-American and Latina mothers and 57 girls (aged 10–13 years) participated in one of 16 focus groups. Thematic analyses were conducted on transcripts of the mothers' and daughters' focus group sessions. Results: Analyses revealed four major themes related to pubertal development: (1) physical maturation provides new social status of maturity; (2) puberty is associated with changes in sexual expectations and roles; (3) girls develop social meanings to feelings of sexual arousal; and (4) puberty prompts changes in mother–daughter relationship control. Representative quotations are used to illustrate each of these themes. Conclusions: Our analyses provide insight into the ways in which late childhood and early adolescent urban girls interpret sexuality and sexual relations, perceive changes in their social relationships, and develop expectations regarding their roles in sexual and romantic relationships.
Understanding Proto-Insurgencies

Abstract Why do some small terrorist and guerrilla groups succeed in becoming full-blown insurgencies while many others fail? Proto-insurgencies face many difficulties in creating an insurgent movement: they must create a politically salient identity, harness a compelling cause, create an effective sanctuary, and defeat both violent and peaceful organizational rivals, all while evading the police and security services of the much more powerful state. Outside support is a mixed blessing for proto-insurgents. Often, the ultimate success of the proto-insurgency in becoming a full-blown insurgency depends on the mistakes of the government it opposes.
Modeling of a three-source perfusion and blood oxygenation sensor for transplant monitoring using multilayer Monte Carlo code

A Multi-Layer Monte Carlo (MLMC) model was developed to predict the results of in vivo blood perfusion and oxygenation measurement of transplanted organs as measured by an indwelling optical sensor. A sensor has been developed which uses three-source excitation in the red and infrared ranges (660, 810, 940 nm). In vitro data was taken using this sensor by changing the oxygenation state of whole blood and passing it through a single-tube pump system wrapped in bovine liver tissue. The collected data showed that the red signal increased as blood oxygenation increased and infrared signal decreased. The center wavelength of 810 nanometers was shown to be quite indifferent to blood oxygenation change. A model was developed using MLMC code that sampled the wavelength range from 600-1000 nanometers every 6 nanometers. Using scattering and absorption data for blood and liver tissue within this wavelength range, a five-layer model was developed (tissue, clear tubing, blood, clear tubing, tissue). The theoretical data generated from this model was compared to the in vitro data and showed good correlation with changing blood oxygenation.
Cognitive-behavioral group treatment for male spouse abusers

Two studies evaluating cognitive-behavioral treatment programs for male spouse abusers are reported.3 Both programs resulted in significant reductions in both indirect and direct threats of violence and direct and severe violence towards spouses. Study 1 identified reduced levels of guilt proneness and increased levels of group conformity as a result of the intervention program. In addition, changes in attitudes toward love were noted from pre- to post-test indicating greater physical attraction, intensity of emotion, and commitment to the lover. Changes were maintained at a six month follow-up. Study 2 evaluated a modified cognitive-behavioral treatment formal that focused more on communication, problem-solving, and sexual attitudes and practices. All levels of violence were significantly reduced and changes in endorsement of sexual attitudes were noted. In addition, males showed lower levels of passive-aggressiveness and increasing levels of narcissism as a function of treatment. Implications for program development and research are discussed.
DABCO Stabilization of Coumarin Dye Lasers

Abstract 1.4-diazabicyclo [2.2.2] octane (DABCO) has been shown to extend the lifetime of several coumarin dyes in nitrogen-laser-pumped and flash-lamp-pumped dye lasers. With 0.010 M DABCO average power output remains at better than 907 of initial power at least three times longer than without DABCO.DABCO is effective in stabilizing dye solutions which are not oxygen degassed and to a lesser extent, in stabilizing oxygen degassed dye solutions. Average power output, pulse duration, and spectral linewidth are not significantly affected. Stabilization is proposed to occur through a combination of dye triplet excited state quenching and quenching of singlet oxygen which results from oxygen quenching of dye triplet states.
Amphibian use of constructed and remnant wetlands in an urban landscape

Urban areas are increasing in number, extent, and human population density worldwide. There is potential to mitigate negative impacts of urbanization to native pond-breeding amphibians by providing habitat in both remnant natural and constructed wetlands. This study examines amphibian use of potential breeding sites in natural and constructed ponds in a large metropolitan area to investigate habitat characteristics that are associated with successful breeding. I surveyed 62 ponds over three breeding seasons in Portland, Oregon, measuring eleven habitat characteristics that may influence their successful breeding: pond depth, nitrate level, aquatic refugia, aquatic vegetation, surrounding vegetation, pond permanence, presence of fish and of introduced bullfrogs, surrounding road density and forest cover, and whether they were constructed or remnant natural ponds. Five of the six native pond-breeding species that occur in the region were regularly found breeding in city ponds. Surrounding forest cover and amount of aquatic vegetation were highly associated with breeding, indicating that preserving and planting vegetation likely benefits urban amphibians. Non-native bullfrogs were not associated with native species richness. Surprisingly, whether a pond was natural or constructed was also only weakly associated with native species breeding, and the trend was towards higher presence for all species in constructed ponds. This indicates that novel, human-dominated areas can provide habitat for these species. Consideration of habitat characteristics associated with breeding success in urban pond management will likely benefit native amphibians in these rapidly expanding landscapes.
The mechanism of the photochemical activity of isolated chloroplasts. II. Quantum requirements.

Abstract 1. 1. Working under conditions of temperature, pH, light wavelength, and light intensity found to be most favorable, the lowest value of the quantum requirement for the Hill reaction was found to be 7.9 ± 0.3 quanta/oxygen molecule. This reproducible value obtained at 6750 A. is probably not the true minimum since experimental errors were almost uniformly in a direction to give higher than minimum values. 2. 2. It is concluded that, although differences may exist between the Hill reaction and whole-cell photosynthesis, energetically the two processes are so similar that the mechanisms of energy utilization are probably identical.
Blockade of excitatory amino acid transporters in the rat hippocampus results in enhanced activation of group I and group III metabotropic glutamate receptors

Abstract The idea that excitatory amino acid transporters (EAATs) can control the activation of specific metabotropic glutamate receptors (mGluRs) was investigated in rat hippocampal slices. Using the accumulation of inositol phosphates as a measure of group I mGluR activity, we have shown that the broad spectrum, non-transportable EAAT blocker, TBOA, produces a significant shift to the left of agonist concentration–response curves. Moreover, this increase in potency did not occur if endogenous glutamate was enzymatically removed, suggesting a glutamate-dependent mechanism. This shift in potency was shown to be NMDA and group II mGlu receptor independent. Additionally, experiments with selective antagonists indicated that the group I receptor responsible for the stimulation of inositol phosphate production in this preparation is likely to be mGluR5. Inhibition of forskolin-stimulated cyclic AMP (cAMP) production was used as an index of group II/III mGluR activity. TBOA produced a rightward shift of the forskolin concentration–response curve. A group III, but not a group II, mGluR agonist also produced this effect, suggesting that the TBOA-mediated increase in glutamate activates a receptor, which appears to be a member of the group III mGluR subset. This was confirmed by the observation that an antagonist of group III mGluRs, prevented the TBOA-induced rightward shift in forskolin potency. These results provide evidence of a role for EAATs in the regulation of mGluR5 and group III mGluRs in the rat hippocampus, which may have therapeutic implications.
A note on separated data and exact likelihood-ratio p-values in logistic regression

Exact conditional p-values based on the likelihood-ratio statistic in logistic regression require accurate computation of the supremum of the likelihood function, particularly for outcomes in the sample space that represent completely-separated or quasi-completely-separated data sets. Current software does not always handle these cases well. Three simple solutions are proposed.
Magma mixing due to disruption of a layered magma body

Abstract Pyroclastic eruptions provide a mechanism for the disruption of a compositionally zoned magma body and can result in the formation of homogeneous mixed magmas. The large volume (> 1200 km3) Topopah Spring ash-flow sheet, represents an eruption from a magma body that contained an abrupt compositional interface between a high-silica rhyolite and a quartz latite. The smaller volume ( km 3 ) Pah Canyon ash-flow sheet overlies the Topopah Spring Member, and represents an eruption of a relatively homogeneous magma that is intermediate in composition to the contrasting magmas of the Topopah Spring Member. We propose a model in which the Pah Canyon magma formed by mixing of the high-silica rhyolite and the quartz latite magma that remained in the magma chamber after the eruption of the Topopah Spring ash-flow sheet. Evaluation of this model, using variation diagrams of the major and trace elements, ratio-ratio plots, and least-squares multiple linear regression indicates that the Pah Canyon magma can be derived by mixing of approximately equal volumes of the high-silica rhyolite and the quartz latite end members. Phenocrysts in the mixed magma have reequilibrated and reflect the new composition, temperature and oxygen fugacity conditions.
A new determination of oxidized and reduced nicotinamide-adenine dinucleotide in tissues.

Abstract A sensitive and simple method for measuring NAD and NADH in the range of 0 to 200 μμmoles is described. The assay is based on the enzymic cycling of NAD and NADH and the sequential conversion of lactate-1- 14 C to 14 CO 2 in the presence of NAD or NADH, Mg ++ , thiamine pyrophosphate, α-ketoglutarate, glutamic dehydrogenase, lactate dehydrogenase, and pyruvate dehydrogenase. Recovery of internal standard added to the tissue extract was approximately 100% and the assay of two different amounts of tissue resulted in equivalent concentrations of NAD or NADH per gram tissue.
Pentad Evolution of Wintertime Impacts of the Madden–Julian Oscillation over the Contiguous United States

AbstractLagged pentad composites of surface air temperature and precipitation are analyzed for the winter season (December–February) to assess the influence of the Madden–Julian oscillation (MJO) on the climate of the contiguous United States. Composites are based on the Wheeler and Hendon MJO index as well as an index developed and maintained at NOAA’s Climate Prediction Center (CPC), which is based on extended empirical orthogonal function analysis of upper-level velocity potential. Significant positive temperature anomalies develop in the eastern United States 5–20 days following Wheeler and Hendon MJO index phase 3, which corresponds to enhanced convection centered over the eastern Indian Ocean. At the same lag, positive precipitation anomalies are observed from the southern Plains to the Great Lakes region. Negative temperature anomalies appear in the central and eastern United States 10–20 days following Wheeler and Hendon MJO phase 7. These impacts are supported by an analysis of the evolution of 2...
Outward currents in developing Drosophila flight muscle

The development of two different voltage-sensitive potassium channels was studied in Drosophila flight muscle by voltage clamp techniques. Early in development active channels are not present in the membrane. The first channels to appear are the A current channels, which carry a fast, rapidly inactivating potassium current. The channels for delayed rectification appear later. Channels carrying inward current also appear only after the A current channels. During development, the A current may be easily studied in isolation from other currents and thus provides a desirable system for studying the genetic determinants of this current.