cssi/SciSciGPT-SciSciNet huggingface dataset:
L-glutamate: a neurotransmitter candidate for cone photoreceptors in the monkey retina

In order to examine whether L-aspartate and L-glutamate are photoreceptor transmitters in monkey retina, we have carried out two different studies: an autoradiographic localization of the high-affinity uptake sites for aspartate (Asp) and glutamate (Glu), and an immunocytochemical localization of the biosynthetic enzyme, L-aspartate aminotransferase (AAT). Our results show that L-Glu is taken up by a sodium-dependent, high-affinity uptake system with a Km = 8 +/- 3.5 X 10(-6) M and a Vmax = 48 +/- 14 X 10(-12) mol/min/mg protein; 3H-L-Glu or 3H-L- and D-Asp are taken up and accumulated by rod somata and inner segments in retinas incubated at 37 degrees C or at ambient temperature; cones accumulate 3H-L-Glu at ambient temperature but not at 37 degrees C. Neither 3H-L-Asp nor D-Asp is accumulated by cones at either temperature; rods and cones show the same labeling pattern irrespective of whether they are located in the central or peripheral retina; and antiserum to AAT preferentially stains the cone somata, inner segments, and synaptic pedicles, while the outer segments are negative. Both foveal and peripheral cones are strongly reactive, but rods show little reactivity. These findings point to the existence of major differences between rods and cones in the uptake and metabolism of L-Asp and L-Glu and are consistent with L-Glu being a cone transmitter in the monkey retina.
Quantifying uncertainty and confusion in land change analyses: a case study from central Mexico using MODIS data

Land cover classifications of coarse-resolution data can aid the identification and quantification of natural variability and anthropogenic change at regional scales, but true landscape change can be distorted by misrepresentation of map classes. The Lerma–Chapala–Santiago (LCS) is biophysically diverse and heavily modified by urbanization and agricultural expansion. Land cover maps classified with a Mahalanobis distance algorithm and possibilistic metrics of class membership were used to quantify uncertainty (potential error in class assignment) and change confusion (potential error in land change identification). While land change analysis suggests that ~33% of the landscape underwent a change in class, led by changes from or to the mosaic class (~19% of landscape), classification uncertainty values for 2001 and 2007 were 0.59 and 0.62, respectively, with highest uncertainty among bare soil classes, and an average confusion index value of 0.65, with pixels experiencing change at 0.67 and pixels experien...
Prognostic indicators in well-differentiated thyroid carcinoma when controlling for stage and treatment.

Objectives/Hypothesis The incidence of thyroid carcinoma is rising. Few studies have examined patient characteristics that influence survival when adjusting for treatment and tumor stage/extent. Study Design Retrospective analysis was performed using the Surveillance Epidemiology and End Results registry data among patients diagnosed with well-differentiated thyroid (WDT) carcinoma during 1988–2009. Methods Kaplan–Meir survival curves were used to estimate 5- and 10-year cause-specific and overall survival differences by sociodemographics, clinical characteristics, and treatment. Multivariate Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results A total of 83,985 patients were identified with WDT carcinoma. Blacks had higher hazard of death at 5 years (HR, 1.67; 95% CI, 1.42-1.96) and 10 years (HR, 1.57; 95% CI, 1.37-1.80) when compared to Caucasians, but there were no significant differences in cause-specific deaths. Hispanics had higher overall and cause-specific 5-year and 10-year hazard of death (5-year cause-specific: HR, 1.56; 95% CI, 1.23-1.99). Age was the most significant predictor of cause-specific and overall survival, with risk increasing in a nonlinear fashion. After age 45 years, the HR for 5- and 10-year cause-specific survival rose drastically, reaching an HR of 153 for individuals aged 85 years and older (HR, 153.45; 95% CI, 97.84–240.67). Conclusions Age was the strongest factor associated with WDT cancer in our study. African Americans had worse overall survival, although only Hispanics had a significantly worse cause-specific survival. These factors should be taken into account in counseling patients and treatment planning. Level of Evidence 2c. Laryngoscope, 125:1021–1027, 2015
Robin-to-Robin Maps and Krein-Type Resolvent Formulas for Schrödinger Operators on Bounded Lipschitz Domains

We study Robin-to-Robin maps, and Krein-type resolvent formulas for Schrodinger operators on bounded Lipschitz domains in ℝn, n ⩾ 2, with generalized Robin boundary conditions.
Use of cytokines in the treatment of acute myelocytic leukemia: a critical review.

PURPOSEThe colony-stimulating factors (CSFs) have been evaluated in patients with acute myelocytic leukemia (AML), both as potential priming agents and during and/or following induction chemotherapy to shorten the period of myelosuppression. The purpose of this review is to evaluate critically the safety and efficacy of the CSFs, primarily granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony stimulating factor (G-CSF), in the treatment of patients with AML.METHODSAll phase III trials that have either been presented or published that used CSFs during and/or following induction chemotherapy in patients with de novo AML are discussed. Relevant background information and future directions are also addressed.RESULTS AND CONCLUSIONThere have been six phase III trials that used either GM-CSF or G-CSF in induction therapy in patients with AML. It is difficult to compare these trials due to differences in patient age, induction therapy administered, disease characteristics, whether leuk...
Effects of Retinal Degeneration and Brain Size upon Spatial Reversal Learning in Mice

Mice selected for high brain weight were superior to unselected controls in initial and reversal learning of a spatial discrimination in a water T-maze. Mice selected for low brain weight were supe...
On characterizing distributions by the ration of variance and mean

Recently SAMPSON (1975) has shown that the mean function is enough to characterize the one parameter exponential family. In this paper we consider the class of modified power series distributions introduced by the author (1974) and exhibit a general method of obtaining the distribution if the ratio variance/mean is known. As illustrations characterizations of the POISSON and the geometric distributions are obtained. Considering the continuous version of the exponential family, it is shown that the equality of mean and standard deviation characterizes the exponential distribution.
Convex control design via covariance minimization

We consider the problem of synthesizing optimal linear feedback policies subject to arbitrary convex constraints on the feedback matrix. This is known to be a hard problem in the usual formulations (ℋ2;ℋ∞;LQR) and previous works have focussed on characterizing classes of structural constraints that allow efficient solution through convex optimization or dynamic programming techniques. In this paper, we propose a new control objective based on eigenvalues of the covariance matrix of trajectories of the system and show that this formulation makes the problem of computing optimal linear feedback matrices convex under arbitrary convex constraints on the feedback matrix. This allows us to solve problems in distributed control (sparsity in the feedback matrices), control with delays and variable impedance control. Although the control objective is nonstandard, we present theoretical and empirical evidence that it agrees well with standard notions of control. We numerically validate the our approach on problems arising in power systems and simple mechanical systems.
Classification and measurement of surface microvessels in man.

Abstract Capillary length, width, and number of loops per field have been measured in human surface microvessels. The nailfold was selected as a testing place because of its easy accessibility, the possibility to photograph the loops in all their functional parts, and because of comparative persistency of nailfold capillary patterns. The method of measurement is described and its limitations discussed. Subjects included for study were 37 individuals without clinical disease, 20 patients with systemic lupus erythematosus (SLE), and 25 patients with progressive systemic sclerosis (PSS). The clinical diagnoses had been established independently by the Rheumatic Disease Study Group at the New York University School of Medicine. The percentage distribution of capillary types found for each group is: normals, 71% within normal limits, 25% tortuous, 2% meandering, 2% general enlargement, and no giant loops; SLE, 21% within normal limits, 44% tortuous, 32% meandering, 3% general enlargement, and no giant loops; PSS, 23% within normal limits, 37% tortuous, 6% meandering, 14% general enlargement, and 20% giant. Measurements of capillary loops in each group have verified preliminary findings of an earlier study, i.e., transitional limb width is greater and the number of capillaries is smaller in PSS than in normals and in SLE. The usefulness of this approach is discussed in terms of possible significance of the findings.
Hydrogen-based carbon fixation in the earliest known photosynthetic organisms

Thin carbonaceous laminations preserved in shallow-water facies of the 3416 Ma Buck Reef Chert, South Africa, have been interpreted to represent some of the oldest-known mats constructed by photosynthetic microbes. Preservation of these mats within a unit containing facies deposited at water depths ranging from 0 m to >200 m provides an opportunity to explore the electron donors employed in early microbial photosynthesis. The presence of siderite (FeCO3) as a primary sediment, lack of hematite (Fe2O3), and lack of cerium anomalies throughout the Buck Reef Chert imply that the entire water column was anoxic despite the presence of photosynthetic organisms. Authigenic uranium (Ua = U–Th/3) correlates inversely with siderite abundance, suggesting that variations in carbonate rather than oxygen activity controlled uranium mobility. The inferred lack of oxygen and ferric minerals and the presence of dissolved Fe2+ in the water column imply that H2O, Fe2+, and H2S could not have served as primary electron donors for carbon fixation. It is most likely that Buck Reef Chert bacteria utilized H2 as the primary reductant for photosynthesis.
Collagen polymorphisms of the intervertebral disc.

The mechanical function and the collagen pheno-type of the disc are complex, each a hybrid of elements of ligament and cartilage. In detail, the collagen properties are unique. Collagens I and II provide the bulk of the tissue fabric interwoven in opposing radial concentration gradients. From analysis of isolated cross-linked peptides, some degree of commingling of these major fibrillar collagens occurs down to the molecular level. Collagens V, VI, IX, XI, XII and XIV all contribute to the matrix. Collagen IX is the short molecular form that lacks a non-collagenous (NC)4 domain, not the long form found in most hyaline cartilages. Protein sequence and reverse transcriptase-PCR analysis confirmed this was the result of expression from the alternative transcription start site, not proteolysis of the long form. In view of recent reports that common single nucleotide polymorphisms in COL9A2 and COL9A3 are linked to chronic sciatica associated with disc pathology, the specific interactions and role of collagen IX in disc tissue are important to define.
Integrated ARROW waveguides for gas/liquid sensing

We present integrated antiresonant reflecting optical (ARROW) structures with hollow cores as a new paradigm for optical sensing of gases and liquids. ARROW waveguides with micron-sized hollow cores allow for single-mode propagation in low-index non-solid core materials where conventional index guiding is impossible. We review design, fabrication and optical characterization of these devices for possible applications in chemical sensing, single molecule fluorescence and Raman spectroscopy, flow cytometry, and pollution monitoring of picoliter to nanoliter volumes. We describe how to determine and control the waveguide loss and dispersion of the ARROW waveguides and design optimization for realistic structures that are compatible with the fabrication constraints. The technology to realize hollow-core waveguides using conventional silicon microfabrication and sacrificial core layers is discussed. We present the first demonstration of waveguiding in integrated ARROW waveguides with both hollow and liquid cores. Single-mode propagation with mode areas as small as 6mm2 and volumes down to 15 picoliters is observed and the loss characteristics of the waveguides are determined. The observation of fluorescence from dye molecules with concentrations of 10 nmol/l is described. Higher-level integration towards compact, planar, and massively parallel sensors on a chip is discussed.
Comparison of the physical properties of 11 soft denture liners.

Abstract Soft denture liners are an important treatment option for patients who have chronic soreness associated with their prostheses. The objective of this study is to determine the tensile strength, elongation, hardness, tear strength, and tear energy of eight plasticized polymers or copolymers, two silicones, and one polyphosphazene fluoroelastomer. Tests were made on samples that were stored in a humidor for 24 hours before testing. The range of data is as follows: tensile strength, 8 to 85 kg/cm 2 ; percent elongation, 150% to 542%; hardness, 25 to 95 Shore-A units; tear energy, 1.43 × 10 6 to 40.4 × 10 6 ergs/cm 2 ; tear resistance, 2.6 to 26.3 kg/cm. It can be concluded that (1) the data obtained can be useful in characterizing the performance of soft denture liners, (2) there is considerable variability in the physical/ mechanical properties of soft denture liners, and (3) the required essential properties for soft denture liners are as yet not known.
A Multiple Values Model of Political Tolerance

While students of political tolerance often view tolerance decisions as a trade-off between opposing values (civil liberties versus other values), there have been few explicit attempts to formulate and test such a multiple-values model. With rare exception, researchers typically examine linkages between tolerance judgments and a single value constellation (civil liberties or general norms of democracy) without examining directly the way people rank competing values. In this essay, we use data from a national telephone survey to test a model of how various value trade-off measures (e.g., value conflict) influence citizens' initial tolerance decisions, as well as their willingness to stick to that judgment in the face of counter-arguments (i.e., the pliability of the initial baseline judgment). We find that while value conflict is often associated with greater political forbearance of disliked groups (e.g., the Klan, flag burners), greater conflict also makes individuals more susceptible to counter-argument...
Relations Between Videogame Play and 8th-Graders' Mathematics Achievement

This study explores whether any relationships exist between math performance scores on the Missouri Assessment Plan MAP, its subscales and time spent playing the child's favorite videogame given the game's spatial content and cognitive complexity. Relationships between gender and math scores were also examined. Findings indicate no main effect of time spent playing, spatial content, or level of complexity of games on math performance. However, several math scores interacted with time spent playing one's favorite video game, such that higher levels of math performance occurred when participants played games high in spatial content at low amounts of time. A similar interaction occurred when examining complexity of the game and time spent playing. The study provides preliminary evidence that it may be important to consider the spatial or complexity content of videogames in addition to time spent playing when addressing the relationship between videogame play and adolescent math performance.
Independence of blood pressure and locomotor hyperactivity in normotensive and genetically hypertensive rat

The spontaneously hypertensive rat (SHR) exhibits locomotor hyperactivity in comparison to its normotensive progenitor Wistar—Kyoto (WKY) strain. We asked whether the hyperactive behavior was a direct consequence of elevated blood pressure in the hypertensive rat. Three experimental protocols were used to chronically alter blood pressure. In the first protocol, a group of adult SHRs was given hydralazine (20 mg/kg/day) in their drinking water to lower blood pressure. These animals exhibited a significant decrease in blood pressure, but no change in locomotor activity. In the second protocol, young SHRs (4 weeks of age) were treated with the same dosage of hydralazine until 16 weeks of age. Blood pressure was significantly decreased in these animals with no change in locomotor activity. In the third protocol, normotensive WKY and Sprague—Dawley (SD) rats were made hypertensive with unilateral renal clips. The resulting increase in blood pressure in these animals did not alter locomotor activity. These results suggest that locomotor hyperactivity is an inherent property of the SHR and is independent of blood pressure.
Limitations on coherently pumped molecular systems for studying two-level laser instabilities

Abstract We present a model for a FIR laser which includes pump coherence and complete molecular relaxation. The model which has five energy levels has been solved analytically and Doppler integrated to generate copropagating and counter-propagating gain curves. The model was applied to NH 3 and includes spatial pump absorption. The results show that sizable two-photon effects occur at low pump powers and that the maximum excitation which has been achieved in experiments is approximately five times above threshold.
Condoms and Connection: Parents, Gay and Bisexual Youth, and HIV Risk

The family has long been considered a powerful influence on youth's high-risk behaviors. However, little is known about preventive family influences for gay and bisexual youth, a group at high risk for HIV infection. For this study, qualitative interviews from a sample of 38 gay and bisexual youth and their parents/guardians underwent a thematic analysis. Youth described parent-child closeness, parental warnings, and urgings to use condoms as influences. Youth denying family influence came from families in which parent-child relationships were disrupted or HIV-related discussion was lacking. Most families reported discomfort discussing HIV risk. These findings, along with a case example, suggest how family therapists can enhance parental influence by helping these families strengthen their relationships and discuss this important topic. Video Abstract.
Interdependence and Its Consequences in Distributor-Supplier Relationships: A Distributor Perspective Through Response Surface Approach

Abstract Despite its importance for marketing channels research, the effect of interdependence on channel outcome variables remains elusive because of the inconsistent manner in which it is operationalized and the analytical methods used to assess its impact. To address those gaps, the authors first review prior approaches and identify the sources of their limitations. Then, the authors use the response surface approach (RSA) and derive three managerial insights that can be garnered from its use. They apply RSA to industrial distributor–supplier relationships and contrast it with previous methods. The empirical study results suggest that distributors perceive differential effects of supplier dependence and distributor dependence on outcome variables. The authors elaborate on managerial and research implications of the RSA results.
In defense of defiance

L'A. se place dans l'alternative de l'acceptation ou du refus de l'autorite. Il expose la these selon laquelle ce conflit est le reflet d'une tension interne a l'autorite entre son normativisme, qui fait appel a un consentement libre de l'individu, et son pouvoir coercitif
Monocytic skin nodules in chronic myelomonocytic leukemia: clinical response to decitabine therapy.

Patients with chronic myelomonocytic leukemia (CMML) exhibit variable impairment of hematopoiesis, similar to patients with myelodysplastic syndrome (MDS), in addition to proliferative cellular fea...
Solution of the Schrödinger equation for a double minimum potential

We apply Richardson's extrapolation to zero mesh size to calculate the dissociation energies and wavefunctions of a double minimum potential curve for the E,F1Sigma(+)g state of H2. We demonstrate that a double minimum potential presents no difficulties and that this extrapolation method is to be preferred over a quadratic extrapolation or the use of a basis expansion.
Chlorambucil-induced cell death in embryonic mouse limb buds.

Abstract A high frequency of congenital limb defects after maternal treatment with the nitrogen mustard chlorambucil suggested that cytotoxic effects could be analyzed as correlates of teratogenic action of this alkylating agent. Limb buds from ICR DUB mouse embryos were exposed in vivo or in vitro to teratogenic doses of chlorambucil. At 0.5- to 72-hr intervals following exposure, the limbs were processed for observation with the light and electron microscopes. Light microscopy of limb buds exposed to the drug in vivo or in vitro showed evidence of cellular involvement within 4 hr following treatment. The effects were manifested in the form of cytoplasmic inclusions which increased in number as the time following exposure increased, and, in vivo, reached a maximum at 24 hr. Increased doses of the drug also produced increased numbers of affected cells. In limb buds exposed to chlorambucil in vitro, the number of affected cells reached a plateau at 48 hr after treatment and decreased significantly by 72 hr, at which time exposure to a second dose of the drug had little or no effect. Affected cells were restricted almost exclusively to regions of undifferentiated mesenchymal cells. Electron microscopic examination of the cytoplasm of affected cells demonstrated the presence of membrane-bound vacuoles containing cellular organelles in various stages of degeneration. The number and size of these vacuoles increased with time following exposure until finally the cells fragmented. Nuclear material was not involved until fragmentation of the cells occurred, at which time the nucleus became pyknotic. Following cellular fragmentation and destruction, macrophages were observed in association with the cellular debris. Acid phosphatase was demonstrated within the vacuoles (by the presence of lead phosphate precipitates) with the electron microscope after incubating limb bud tissue in a buffered solution of β-glycerophosphate/lead nitrate. The amount of demonstrable enzyme was found to increase as the degree of breakdown within vacuoles increased. These results and the histological information provided evidence consistent with a process of autophagocytosis.
On the Measurement of the Permanent Component of a Series

Abstract In a recent article [9] J.M. Holmes has derived a necessary condition for the statistical independence of the permanent and transitory components of an observed series when the permanent component is defined as a weighted average of the observed series. In this article a weighting scheme satisfying Holmes' necessary condition is discussed and an extension of the stochastic specification in [9] is considered.
Analysis of fixed effects linear models under heteroscedastic errors

Abstract In this article we develop a new test procedure for testing a linear hypothesis in a fixed effects linear model with heteroscedastic errors. This test is based on the ordinary least squares estimator (OLSE) of the regression parameter and uses the variance estimator of OLSE that accounts for heteroscedasticity. The null distribution of this statistics is approximated by a multiple of central F distribution. Simulation studies suggest that the new critical region performs well both in terms of size and power.
Compositional homogeneity in processing precursor powders to the Ba2YCu3O7−x high Tc superconductor

We have used scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS) to study compositional homogeneity at several stages in the processing of powders to the Ba 2 YCu 3 O x high T c superconductor. We investigated the effects of solution pH and ionic concentration in the precipitation preparation of mixed hydroxycarbonates of Ba, Y, and Cu as precursor to the Ba 2 YCu 3 O 7− x high T c superconductor. Our results show that both powder homogeneity and particle morphology are strongly dependent on these parameters. Additionally, studies of the compacted powders by EDS mapping at successive stages of processing show the development of phase inhomogeneities even in homogeneous starting powders.
Focal shift for a Gaussian beam: an experimental study

The beam radius along a focused, unapertured Gaussian beam was measured and used to calculate the dependence of the geometrical Fresnel number on the effective Fresnel number of the beam as it emerged from the focusing lens. The resulting data clearly demonstrate a focal shift away from the focal plane given by geometrical optics. The data agree very well with a theory due to Carter. This theory indicates that a significant focal shift occurs in these beams if the focusing lens is placed within the near field of the focal plane.
Hydrodynamic Study of a Water-Propelled Rocket: An Undergraduate Experiment in Fluid Mechanics

An undergraduate experiment has been developed to measure the performance of a pressurized water rocket and compare test data to an analytical model developed from fluid momentum. A rocket and test stand were developed to measure the net thrust of the rocket, as well the air pressure and temperature inside the rocket, as a function of time. The model compares well to test data from four conditions, combinations of two initial water heights and two initial air pressures. The air in the rocket was assumed to under go polytropic expansion, and a value of 1.1 for the polytropic exponent was found to best fit the model to all experimental conditions. Experimental observations also reveal that, at higher air pressures, the air mixes with the expelled water, resulting in a two-phase flow that reduces the net thrust of the rocket. A pedagogical approach is also developed for the experiment and is described indetail.Copyright © 2005 by ASME
Transgenic porcine valves show no signs of delayed cardiac xenograft rejection.

Abstract Background . Glutaraldehyde fixation stiffens the structural integrity of porcine valves, although the solution also destroys tissue viability and accelerates calcification. Recently, we demonstrated that fresh cardiac valves from domestic pigs do not express the galactose α1, 3 galactose (α-Gal) antigen and may be immunologically unique. The absence of α-Gal explained why the valves remained pristine while the rest of the porcine heart was destroyed by primate immunoglobulin M (IgM) and complement membrane attack complex (MAC) within 60 minutes. We sought to clarify whether fresh porcine valves from transgenic pigs bearing human complement regulatory proteins (CD59/DAF) can survive longer in primates and whether porcine cardiac valves remained immunologically privileged after prolonged exposure. Methods . Tissue sections from wild-type untransplanted (n = 6), wild-type transplanted (n = 3), and transgenic pigs expressing human CD59/DAF proteins transplanted (n = 3) porcine-to-primate cardiac grafts were examined by hematoxylin and eosin, and by immunohistochemistry for the porcine endothelial marker (GalNac), α-Gal, primate IgM and MAC. Results . α-Gal antigens were highly expressed on the vascular, but not valvular, endothelium of transgenic pigs. Hearts from CD59/DAF transgenic pigs survived 5, 7, and 11 days, but showed increasing IgM and MAC deposition until failure. Valves remained morphologically intact at explant, and strong GalNac staining suggested an intact endothelial surface. However, the valves showed no signs of IgM- or MAC-mediated damage. Conclusions . Although hearts from transgenic pigs expressing human complement regulatory proteins can survive for days in the primate recipient, the xenografts eventually fail because of escalating attacks of primate IgM and MAC. The absence of the α-Gal antigens protects unfixed porcine valves from rejection.
Admission Control with Incomplete Information of a Queueing System

We consider a multiple-server loss model where customers arrive at a gatekeeper according to a Poisson process. A costc is incurred if a new arrival is blocked from entering the system by the gatekeeper, while a larger costK is incurred if an admitted customer finds all servers busy and therefore has to leave the system. The key assumption is that the gatekeeper is informed when an admitted customer finds all servers busy, but is not informed when served customers depart. Assuming an exponential service distribution, we show that, in the case of a single server, a threshold-type policy that blocks for a certain amount of time after a new arrival is admitted is optimal. When there are multiple servers, we propose two types of heuristic policies. We analytically compute the best policy of the first type, and use simulation to estimate that of the other.
Lipid microencapsulation of hemoglobin.

The idea of microencapsulating a solution of hemoglobin (Hb) to make a prototypal artificial red blood cell (RBC) has been around for decades. T.M.S. Chang discussed the possibility in the late 50s and early 60s. The ideal properties and characteristics of a transfusable suspension of microencapsulated Hb have been specified. Progress has been limited by three major obstacles: (i) selecting an acceptable microencapsulation material; (ii) developing a microencapsulation process that yields the desired size range, but avoids denaturation of Hb; and (iii) encapsulating sufficient Hb while maintaining an acceptable final viscosity. We have made considerable progress in all three fronts. The resulting microcapsules are called Neohemocytes.
Improved Surgical Outcome After Fetal Diagnosis of Hypoplastic Left Heart Syndrome

Background—Hypoplastic left heart syndrome (HLHS) is frequently diagnosed prenatally, but this has not been shown to improve surgical outcome. Methods and Results—We reviewed patients with HLHS between July 1992 and March 1999 to determine the influence of prenatal diagnosis on preoperative clinical status, outcomes of stage 1 surgery, and parental decisions regarding care. Of 88 patients, 33 were diagnosed prenatally and 55 after birth. Of 33 prenatally diagnosed patients, 22 were live-born, and pregnancy was terminated in 11. Of 22 prenatally diagnosed patients who were live-born, 14 underwent surgery, and parents elected to forego treatment in 8. Of 55 patients diagnosed postnatally, 38 underwent surgery, and 17 did not because of parental decisions or clinical considerations. Prenatally diagnosed patients were less likely to undergo surgery than patients diagnosed after birth (P=0.008). Among live-born infants, there was a similar rate of nonintervention. Among patients who underwent surgery, survival...
Mechanism of environmental stress cracking in linear polyethylene

By means of a constant stress test, the environmental stress-cracking behavior of linear polyethylene has been studied on a macro and micro scale in an effort to determine the mechanism of the process. Upon the application of stress, linear polyethylene develops a network of very fine, elliptical fissures, the edges of which are connected by cold-drawn material. In the absence of an active environment, these fissures slowly grow and interconnect, resulting ultimately in the formation of a “neck.” When exposed to an active environment, however, the cold-drawn material ruptures as it is formed at the tips of the fissures. Unsupported, these fissures grow rapidly and interconnect resulting in sample failure. Fissures form both around and through the centers of spherulites with less cold drawing occurring at the interspherulite boundaries. Macroscopic studies confirmed the observation that active environments attack stressed polyethylene specifically at microzones of cold drawing. The effect of low molecular weight hydrocarbon species on the stress-crack resistance of linear polyethylene was evaluated. The role of flaws in the process is also discussed. Attempts have been made to establish a criterion of environmental activity. All of the active stress-cracking agents studied were found to reach similar levels of absorption in polyethylene; however, the specific chemical nature of the environment and not merely its level of absorption determines its ability to cause stress cracking.
Simultaneous determination of six HIV nucleoside analogue reverse transcriptase inhibitors and nevirapine by liquid chromatography with ultraviolet absorbance detection

Abstract An accurate, sensitive and specific reversed-phase high-performance liquid chromatography assay for the simultaneous quantitative determination of the nucleoside reverse transcriptase inhibitors zalcitabine, lamivudine, didanosine, stavudine, zidovudine, and abacavir with the non-nucleoside reverse transcriptase inhibitor nevirapine in human blood plasma is described. The new Polarity dC C18 silica column used in this method provides better resolution and peak shape than all other columns tested. Also, four different ultraviolet wavelengths were used for accurate and specific quantitation of the analytes. The method was validated over the range of 10–10 000 ng/ml for all analytes except zalcitabine (10–5000 ng/ml). This method is accurate (average accuracies of three different concentrations ranged from 97.2 to 105%), and precise (within- and between-day precision measures ranged from 0.5 to 5.1% and 0.5 to 5.6%, respectively), and is currently being used for determination of plasma drug concentrations in our laboratory.
A world of brands: higher education and the emergence of multinational quality franchises

This article explores the concepts of brand and franchise in the development of international quality assurance. The impact of corporate language and culture on higher education is evident and has been extensively analysed. Recent attention given to branding of universities reflects the ever-growing influence of corporate language and ideas. This article presents a conceptual exploration, grounded in a case study that documented the accreditation process of a Mexican university by a United States (US) regional agency. Discourses of exclusivity and legitimacy were widespread in the case; US accreditation was construed as a symbol of international quality given that US higher education hosts world-renowned universities with reputations that, like brands, can be franchised internationally. It is argued here that such new developments warrant further study and critique.
Learning to Solve a Problem A Microanalysis of the Solution Strategies of Children with Learning Disabilities

Ten subjects with learning disabilities and 10 normally achieving subjects, aged 10-5 to 12-5 years, were videotaped while attempting to solve the Tower of Hanoi problem (see Karat, 1982; Piaget, 1976; Simon, 1975). A microanalysis of their problem-solving activities provided a descriptive taxonomy used to analyze what, in fact, individual subjects did when constructing a solution strategy, and to categorize and compare changes in strategy. The results indicated that as a group the normally achieving subjects reached more sophisticated levels of strategy use (p< .05). However, if the focus of the comparison is on an analysis of how learning proceeded in individuals, then the subjects with learning disabilities appear to be similar to the normally achieving subjects. There was no evidence in these subjects of the popular conception that individuals with learning disabilities are inactive, passive, or maladaptive in their attempts to learn to solve a problem.
Dream Deprivation: an Experimental Reappraisal

DEMENT1, using the rapid eye movement method of dream detection, prevented subjects from dreaming on five successive nights by awakening them at the onset of each rapid eye movement period (REMP). The results included a steady increase in the forced awakenings necessary during the deprivation period, a marked increase in the percentage of dream time when subjects were allowed to sleep undisturbed and certain behavioural changes summarized as “anxiety, irritability, and difficulty in concentration”. From a psychiatric point of view we felt the implications of this apparent ‘need to dream’ were significant. We therefore elected to carry out a dream curtailment of our own to assess any quantitative or qualitative psychic changes through continual observation and psychometric testing.
A respiratory rate of ≥60 breaths per minute had high sensitivity for detecting hypoxia in infants

Source Citation Rajesh VT, Singhi S, Kataria S. Tachypnoea is a good predictor of hypoxia in acutely ill infants under 2 months. Arch Dis Child. 2000 Jan;82:46-9. 10630912
REMOVAL OF MG2+ INHIBITION OF CARDIAC RYANODINE RECEPTOR BY PALMITOYL COENZYME A

45Ca2+ fluxes and planar bilayer recordings indicated that the fatty acid metabolise palmitoyl coenzyme A, but not free coenzyme A or palmitic acid, stimulated the cardiac ryanodine receptor channel of pig heart sarcoplasmic reticulum. Palmitoyl CoA reactivated channels inhibited by concentrations of cytoplasmic free Mg2+ in the physiological range. Reactivation by palmitoyl CoA in the presence of Mg2+ was stimulated by myoplasmic free Ca2+ in the micromolar range. Acyl coenzyme A derivatives may be utilized by cardiac muscle cells to compensate for the severe Mg2+ inhibition of ryanodine receptors which would otherwise leave Ca2+ stores unresponsive to Ca2+ and to other cytosolic ligands involved in signal transduction.
Gamma-ray bursts: Magnetism in a cosmic blast

Astronomers know little about γ-ray bursts other than that they are the most energetic explosions in the Universe. The latest observations indicate that large-scale magnetism contributes to their power.
A unified view of ostensibly disparate isoperimetric variational problems

A class of isoperimetric variational calculus problems is solved. It is shown that the said class ties together seemingly dissimilar optimal control problems in economics and physics, to wit, the classical nonrenewable resource extracting model of the firm, the model of the patient worker, and the principle of maximum entropy. In particular, it is shown that a certain family of wealth maximizing nonrenewable resource extracting firms extract at the rate that maximizes the entropy of extraction, and that patient intertemporal utility maximizing individuals do not procrastinate and maximize the entropy of leisure.
Initiating joint-attention treatment facilitates later expressive language development, particularly in initially low-verbal children with autism spectrum disorder1

(1) Does staff-implemented, clinic-based, short-term (12 weeks) teaching of joint attention facilitate autistic preschoolers’ language development 12 months later? (2) Do children with more advance...
THE THERMODYNAMICS OF LANTHANIDE COMPLEXING BY ACETYLACETONATE

Abstract The thermodynamic parameters for the formation of the 1:1 complex between lanthanide ions and acetylacetonate in an aqueous medium of 0.10 M (NaClO4) are reported. These complexes are less stable than the analogous tropolonate complexes due to less exothermic enthalpies of chelation.
Highly nonproductive complexes with Anabaena ferredoxin at low ionic strength are induced by nonconservative amino acid substitutions at Glu139 in Anabaena ferredoxin:NADP+ reductase.

Ferredoxin (Fd) and ferredoxin:NADP + reductase (FNR) from Anabaena function in photosynthetic electron transfer (et). The et interaction between the FNR charge-reversal mutant E139K and Fd at 12 mM ionic strength (I) is extremely impaired relative to the reaction with wt FNR, and the dependency of kobs on E139K concentration shows strong upward curvature at protein concentrations g10 IM. However, at values of I g 200 mM, reaction rates approach those of wild-type FNR, and normal saturation kinetics are observed. For the E139Q mutant, which is also significantly impaired in its et interaction with Fd at low FNR concentrations and low I values, the dependency of kobs on E139Q concentration shows a smaller degree of upward curvature at I ) 12 and 100 mM and shows saturation kinetics at higher values of I. wt FNR and the E139D mutant both show a slight amount of upward curvature at FNR concentrations >30 I Ma tI ) 12 mM but show the expected saturation kinetics at higher values of I. These results are expained by a mechanism in which the mutual orientation of the proteins in the complex formed at low ionic strength with the E139K mutant is so far from optimal that it is almost unreactive. At increased E139K concentrations, the added mutant FNR reacts via a collisional interaction with the reduced Fd present in the unreactive complex. The et reactivity of the low ionic strength complexes depends on the particular amino acid substitution, which via electrostatic interactions alters the specific geometry of the interface between the two proteins. The presence of a negative charge at position 139 of FNR allows the most optimal orientations for et at ionic strengths below 200 mM.
Alternative Approximations for Integrated Control/Structure Aeroservoelastic Synthesis

A discussion of alternative complex pole and gust response approximations is presented, motivated by the need to extend nonlinear programming/approximation concepts optimization methodology from structural synthesis to the integrated control/structure synthesis. Two new approximations are presented for the high-order, weakly damped linear time-invariant systems representing actively controlled airplanes in high-speed flight. They are compared with Taylor series, differential equations, and Rayleigh quotient approximations
Development and use of a confocal microendoscope for in vivo histopathologic diagnosis

A confocal microendoscope for in vivo imaging at the cellular level has been developed. The system consists of a slit-scanning confocal microscope coupled to a fiber optic imaging bundle with a miniature objective lens and focusing mechanism at the distal tip of the catheter. The system is used primarily for imaging tissue fluorescence--either autofluorescence or fluorescence from an exogenous compound. The microendoscope has a lateral resolution of 2 micrometers allowing visualization of structures at the cellular level, and because it is confocal, it can image at selected depths below the tissue surface. Excellent in vivo imaging results have been obtained in animal models and encouraging ex vivo results have been achieved with human tissue.
Josephson junction detector for astronomical applications

A wide-band detector for the 1.0 to 1.6 mm atmospheric transmission window has been developed for astronomical observations at the McDonald Observatory 2.7 m optical telescope. For observations of continuum astronomical sources, the relevant figure of merit is the « Noise Equivalent Temperature » or δ Trms. The present δ Trms = 0.25 K for a 1 s observation. The astronomical objects which have been observed so far include the sun, moon, Venus, Jupiter, 3C 273 and the galactic center. With the present detector sensitivity, a 1 mm source of 0.7 flux units would give a signal to noise of one for a 3 h observation at the NRAO 11 m telescope. The detector uses a point contact Josephson junction, with a niobium point against tin. The junction is mounted coaxially in a multimode 5 mm diameter cylindrical cavity which is coupled by a cone to a 5 mm oversize circular wave guide leading up the neck of the dewar. The wide-band mode of operation is used, in which the incident continuum radiation from an astronomical source causes a depression of the junction critical current. The junction is biased with a 20 Ω source resistance, and the change in bias voltage due to the change in the junction critical current is measured. Two modes are used to chop the 1 mm radiation incident on the junction. For bright astronomical sources such as the sun and the moon, a total power chopper at the entrance of the wave-guide alternately opens and closes the radiometer entrance. For faint sources, a differential chopper chops between the source and adjacent sky.
A New Species of Aphid on Sugar Maple (Aphidae: Homoptera)

Drepanaphis simpsoni , on Acer saccharum in Canada and the northeastern United States is described and compared with D. acerifoliae Thomas.
Sourceless static Yang-Mills systems

Kalb's ansatz for static Yang-Mills systems is investigated in the case of vanishing external sources. A radially symmetric solution is found which signals the presence of a point magnetic monopole with unit magnetic charge. This solution is seen to solve the 't Hooft--Polyakov ansatz for the spontaneously broken Georgi-Glashow model in the limit of vanishing Higgs fields.
Rotational distortion in linear molecules arising from l-type resonance

Abstract It is pointed out that in linear molecules where rotational distortion of the energy levels arises out of l-type resonance alone that the expansion of the energies in powers of J(J + 1) is frequently invalid except for small values of J. An application of the refined theory is made to the band 2ν2 in the spectrum of DCN and the band ν4 + ν5 in the spectrum of C2H2. It is further pointed out that in molecules where Fermi resonance and l-type resonance occur simultaneously, the expansion of the energies in powers of J(J + 1) is valid for strong Fermi coupling but that for weak Fermi coupling, care must be exercised since here the expansion method may break down. Finally it is indicated that rotational distortion of the variety discussed does not occur in π vibration states.
Finite-temperature radiative corrections to Compton scattering.

We calculate the finite-temperature {alpha}{sup 3} corrections to the differential and total Compton scattering cross sections. We find that it is necessary to include soft photon absorption and emission diagrams to cancel the infrared divergences in the cross section. The cross sections are evaluated for the case where the initial electron is at rest.
Digital particle image velocimetry/thermometry and application to the wake of a heated circular cylinder

Digital particle image velocimetry/thermometry (DPIV/T) is a technique whereby the velocity and temperature fields are obtained using thermochromic liquid crystal (TLC) seeding particles in water. In this paper, the uncertainty levels associated with temperature and velocity measurements using DPIV/T are studied. The study shows that large uncertainties are encountered when the temperature is measured from individual TLC particles. Therefore, an averaging procedure is presented which can reduce the temperature uncertainties. The uncertainty is reduced by computing the average temperature of the particles within the common specified sampling window used for standard DPIV. Using this procedure, the velocity and temperature distributions of an unsteady wake behind a heated circular cylinder are measured experimentally at Re=610. The instantaneous DPIV/T measurements are shown to be useful for computing statistical flow quantities, such as mean and velocity-temperature correlations.