cssi/SciSciGPT-SciSciNet huggingface dataset:
Protein Crowding Modulates the Shape and Content of Curved Membranes and Coated Vesicles

Curved membranes are an essential feature of dynamic cellular structures including endocytic pits, filopodia, viral buds, and most organelles. Proteins with specific, curvature-promoting structural motifs, such as crescent-shaped BAR domains and amphipathic helix insertions, have been identified, yet we lack an understanding of how they function in the complex cellular environment. Based on in vitro and live cell experiments, we demonstrate an additional mechanism of membrane bending that originates from the crowded nature of cellular membrane surfaces - protein-protein steric pressure. Specifically, using fluorescence and electron microscopy to correlate membrane curvature with the density of membrane-bound proteins, we demonstrate that lateral pressure generated by protein-protein collisions is a potent driver of membrane bending. These findings reveal an efficient mechanism by which the crowded protein environment on the surface of cellular membranes can be manipulated to define membrane shape. More specifically, results of live cell studies suggest that the shape and molecular content of clathrin-coated pits are strongly influenced by a balance of steric pressure on the two sides of the plasma membrane.
Sevoflurane binds and allosterically blocks integrin lymphocyte function-associated antigen-1.

Background: Volatile anesthetics have been shown to modify immune cell functions via several mechanisms, some of which have been only partially elucidated. We demonstrated that isoflurane inhibits primary leukocyte integrin lymphocyte function-associated antigen-1 (LFA-1) by binding to the allosteric cavity critical for conformational activation to its high-affinity form. It remains to be determined whether the allosteric inhibition of LFA-1 by isoflurane can be generalized to other anesthetics such as sevoflurane. Methods: The effects of sevoflurane on the ability of LFA-1 to bind to its counter-ligand, intercellular adhesion molecule-1, was studied in leukocytes by flow cytometry. To examine whether sevoflurane acts directly on LFA-1, we measured ligand-binding using beads coated with purified LFA-1 protein. To distinguish between competitive versus allosteric inhibition, we analyzed the effects of sevoflurane on both wild-type and mutant-locked high-affinity LFA-1. One-way analysis of variance was employed for statistical analysis of the data. Nuclear magnetic resonance spectroscopy was used to identify sevoflurane binding site(s). Results: Sevoflurane at clinically relevant concentrations inhibited the ligand-binding function of LFA-1 in leukocytes as well as in cell-free assays (P < 0.05). Sevoflurane blocked wild-type but not locked high-affinity LFA-1, thereby demonstrating an allosteric mode of inhibition. Nuclear magnetic resonance spectroscopy revealed that sevoflurane bound to the allosteric cavity, to which LFA-1 allosteric antagonists and isoflurane also bind. Conclusions: This study suggests that sevoflurane also blocks the activation-dependent conformational changes of LFA-1 to the high-affinity form. The allosteric mode of action exemplified by sevoflurane and isoflurane via LFA-1 might represent one of the underlying mechanisms of anesthetic-mediated immunomodulation.
Reproductive health care delivery.

Q6 KEY POINTS Most patients in the United States with reproductive health disorders are not covered by their health insurance for these problems. Health insurance plans consider reproductive care as a lifestyle choice not as a disease. If coverage is provided it is, most often, directed to female factor infertility and advanced reproductive techniques, ignoring male factor reproductive disorders. This article reviews the history of reproductive health care delivery and its present state, and considers its possible future direction.
The non-epistemology of intelligent design: its implications for public policy

Intelligent design creationism (ID) is a religious belief requiring a supernatural creator’s interventions in the natural order. ID thus brings with it, as does supernatural theism by its nature, intractable epistemological difficulties. Despite these difficulties and despite ID’s defeat in Kitzmiller v. Dover Area School District (2005), ID creationists’ continuing efforts to promote the teaching of ID in public school science classrooms threaten both science education and the separation of church and state guaranteed by the U.S. Constitution. I examine the ID movement’s failure to provide either a methodology or a functional epistemology to support their supernaturalism, a deficiency that consequently leaves them without epistemic support for their creationist claims. My examination focuses primarily on ID supporter Francis Beckwith, whose published defenses of teaching ID, as well as his other relevant publications concerning education, law, and public policy, have been largely exempt from critical scrutiny. Beckwith’s work exhibits the epistemological deficiencies of the supernaturally grounded views of his ID associates and of supernaturalists in general. I preface my examination of Beckwith’s arguments with (1) philosopher of science Susan Haack’s clarification of the established naturalistic methodology and epistemology of science and (2) discussions of the views of Beckwith’s ID associates Phillip Johnson and William Dembski. Finally, I critique the religious exclusionism that Beckwith shares with his ID associates and the implications of his exclusionism for public policy.
Modification of arterial blood pressure in rats following microinjection of drugs into the posterior hypothalamus

Summary Microinjections of histamine, norepinephrine or several cholinergic substances into the posterior hypothalamus of rats resulted in various effects on arterial blood pressure. Centrally injected histamine and norepinephrine produced an immediate rise in blood pressure. Carbachol usually produced a hypotensive response but on occasion a delayed rise in blood pressure or an immediate fall followed by a rise was observed. Pronounced changes in respiratory rate accompanied the rise in arterial blood pressure. The hypotensive response, which was also produced by acetylcholine and oxotremorine (a muscarinic agent) but not by nicotine, was mediated both centrally and peripherally by muscarinic mechanisms. Eserine, which produces a rise in blood pressure following systemic administration, caused a similar effect upon injection into the hypothalamus.
Linear dynamic approximation theory

Abstract We study in detail the behavior of some known learning algorithms. We estimate the sum of the squares of the absolute relative errors of some general linear learning algorithms and the sum of the squares of the coefficients obtained by the perceptron algorithm. We prove the convergence of a statistical learning algorithm. The possibility of applications of this theory to biology is discussed.
Personal Epistemology of Urban Elementary School Teachers.

Personal epistemology, originating from social construction theory, provides a framework for researchers to understand how individuals view their world. The Attitudes About Reality (AAR) scale is one survey method that qualitatively assesses personal epistemology along the logical positivist and social constructionist continuum; however, the literature primarily reflects women working in a mental health facility and undergraduate students. This study uses the AAR to examine the personal epistemology of 73 elementary school teachers, the large majority of whom were female, working in an urban and highly diverse public school system in the Northeast, and compares the AAR score to demographic data. The results suggest a more logical positivist orientation than has been observed with other populations although demographic information did not assist in understanding the findings. Implications for the urban elementary school environment, classroom interventions, and collaboration with other support professional...
ON THE STABILITY OF (001) CSL TWIST BOUNDARIES IN MgO : A THEORETICAL STUDY

The energies of (001) coincident-site twist boundaries in MgO have been calculated by means of a computer code developed in recent years. Both the empirical interionic potentials of Catlow, Faux, and Norgett as well as the electron gas potentials of Mackrodt and Stewart have been applied. It is concluded that, in contradiction to the MgO bicrystal experiments of Sun and Balluffi, (001) grain boundaries in pure MgO are unstable above room temperature since their main cohesive force arises from rather weak Van-der-Waals attractive interactions between oxygen ions on opposite sides of the interface, while Coulomb interactions do not contribute to the cohesion. A calculation of the binding energy of the isovalent substitutional impurities Fe^ and Ca'+ to the Z = 5 boundary on the one hand and to the free (001) surface on the other yields the interesting result that impurities may contribute to the stabilization of such bicrystals since they may be bound more tightly to the grain boundary than to the free surface. It is therefore concluded that Sun and Balluffi's bicrystals have been stabilized by substantial amounts of impurities having migrated into the grain boundary during the high-temperature pressure-sintering process.
Using Information Architecture to Evaluate Digital Libraries

Information users face increasing amounts of digital content, some of which is held in digital library collections. Academic librarians have the dual challenge of organizing online library content and instructing users in how to find, evaluate, and use digital information. Information architecture supports evolving library services by bringing best practice principles to digital collection development. Information architects organize content with a user-centered, customer oriented approach that benefits library users in resource discovery. The Publication of Archival, Library & Museum Materials (PALMM), a cooperative digital initiative of the state university libraries of Florida, demonstrates the value of information architecture to digital libraries.
The relationship of weight-height indices of obesity to body fat content.

The measurement called desirable body weight (DBW) was derived by actuaries to indicate that weight which is associated with the lowest mortality. Percent deviation from DBW has become a standard measure of fatness. A different obesity index, body mass index (BMI), is weight in kilograms divided by the square of height in meters. Many workers consider both measures inferior to the measurement of body fat content (BFC). We compared the three measures of fatness in 40 men aged 18-50 and 48 women aged 21-47, ranging from nonobese to extremely obese. Total BFC was determined by isotope dilution of 3H-labeled water. DBWs used were those listed in the US Air Force Examination Manual of 1971; these approximate the midpoint of the range of medium-frame values in the 1959 Metropolitan Life Insurance Tables, but have the advantage of providing a single value for each height. We found nearly perfect correlation (r = 0.99, p < 0.001) between BMI and percent deviation from DBW in both men and women ranging from 14% be...
Models and algorithms for structured layout

Abstract A classification of algorithms used for placement in structured layout is proposed. The mathematical roots of popular placement techniques are investigated and their relations with classical combinatorial problems established. New facts about known heuristics are proved and new heuristics introduced. In conclusion, a comparison of the performance of different heuristics is made for real designs and the application of several algorithms to the same problem recommended as a means for improving the quality of the results.
Reduction and operative fixation ofsalter-harris type II fractures of the distal femur

Abstract The Salter-Harris type 11 fracture is the most common fracture involving the distal femoral physis. This fracture is frequently associated with premature closure of the central physis with resultant limb shortening. To maintain alignment, the majority of these injuries will require fixation with smooth pins or cannulated screws. Techniques of reduction and fixation and postoperative care are described.
A new methane control and prediction software suite for longwall mines

Abstract This paper presents technical and application aspects of a new software suite, MCP (Methane Control and Prediction), developed for addressing some of the methane and methane control issues in longwall coal mines. The software suite consists of dynamic link library (DLL) extensions to MS-Access TM, written in C++. In order to create the DLLs, various statistical, mathematical approaches, prediction and classification artificial neural network (ANN) methods were used. The current version of MCP suite (version 1.3) discussed in this paper has four separate modules that (a) predict the dynamic elastic properties of coal-measure rocks, (b) predict ventilation emissions from longwall mines, (c) determine the type of degasification system that needs to be utilized for given situations and (d) assess the production performance of gob gas ventholes that are used to extract methane from longwall gobs. These modules can be used with the data from basic logs, mining, longwall panel, productivity, and coal bed characteristics. The applications of these modules separately or in combination for methane capture and control related problems will help improve the safety of mines. The software suite's version 1.3 is discussed in this paper. Currently, it's new version 2.0 is available and can be downloaded from http://www.cdc.gov/niosh/mining/products/product180.htm free of charge. The models discussed in this paper can be found under “ancillary models” and under “methane prediction models” for specific U.S. conditions in the new version.
Prevalence and risk factors for gastroesophageal reflux disease in an impoverished minority population

Summary Background and Aims An epidemiological link between an increased body mass index and complaints of typical heartburn symptoms has been identified. It appears that increasing waist circumference, rather than overall weight is most important. Studies to date have not included minority, impoverished communities. Our aim was to determine the impact of obesity on the prevalence of reflux disease in an impoverished community while controlling for known confounders. Methods Design : Cross-sectional survey delivered by in-home interviews, convenience sampling, and targeted mailing. Data queried include demographics, medical history, lifestyle habits, and symptoms of reflux disease. Height, weight, hip and waist circumference measured in participating subjects. Participants : 503 subjects living in the zip code immediately surrounding Temple University Hospital. Included only adults living in the hospital's zip code for at least 3 years. Results The highest quartile of waist circumference (≥42in.) demonstrated a strong association with GERD (AOR=2.15; 95% CI 1.18–3.90). Smoking increased the odds by 1.72 (95% CI 1.13–2.62). There was no relationship between body mass index, waist–hip ratio, or diet and reflux classification. Conclusions Increasing waist circumference, but not overall body mass index or waist–hip ratio, and smoking are risk factors for prevalent GERD. No association between reflux disease and lifestyle choices such as coffee drinking and fast food dining were found. Limitations Potential for recall bias and disease misclassification. Possible methodological errors in self-measurement of waist and hip circumference.
Innervation of the human anterior urethra by the dorsal nerve of the penis

Previous neuroanatomic studies have demonstrated that branches of the dorsal nerve of the penis (DNP) innervate the anterior urethra. This study utilized electrodiagnostic techniques to confirm this finding. Electrical stimulation of the urethra resulted in responses recorded in the main trunk of the DNP, and responses were recorded from the urethra following stimulation of the DNP. A bulbocavernosus reflex was evoked after urethral stimulation. Urethral afferent impulses have a role in reflex ejaculatory function.
Hydrolysis of l-phenylalanine mustard (melphalan). II. Further observations on the effects of pH, chloride ions and buffers on the rate of reaction

Abstract The effects of pH (3.7—13), ionic strength, buffer composition (acetate, phosphate and borate) and buffer concentration (15–200 mM) on the rate of degradation of melphalan in the presence 0.3 M chloride at 50 ± 0.1 °C were investigated using high-performance liquid chromatography. In addition, the data published in the literature for the degradation of phosphoramide mustard have been compared with those of melphalan, placing emphasis on mechanisms of hydrolysis and the effects of pH and chloride. In the presence of chloride, the degradation rate of melphalan was influenced by pH and buffer composition but not by ionic strength. These effects were not seen in the absence of added chloride and have been explained in terms of competition between chloride and other nucleophiles such as the hydroxide ion, water and buffer components for the active intermediate of the alkylating agent. These results help to explain differences in reported values for the rates of hydrolysis of various alkylating agents in the presence of chloride.
Impact of frequency compression on music perception.

AbstractObjective: To determine the effects of frequency compression on music perception, and the impact of previous music training and hearing status. It was hypothesized that lesser amounts of compression would be preferred, and that this pattern of preference would be more evident in the musically trained groups. Design: A paired-comparison paradigm was used. Subjects listened to pairs of musical passages as processed by a hearing aid with different frequency-compression settings. Subjects indicated their preferred passage and the strength of their preference. Study sample: Fifty-seven subjects divided in four groups, according to hearing status (normal hearing, mild-to-moderate hearing loss), and previous music experience (trained, not trained). Results: Subjects generally preferred the conditions with the lesser amount of compression. Listeners in the group with previous music training showed stronger preference for less compression than those without training, as did listeners with normal hearing wh...
The Second World Robotic Urology Symposium.

In this Wrst issue of the second volume of Journal of Robotic Surgery, we acknowledge the successful completion of the Second World Robotic Urology Symposium, held in Columbus, Ohio on 26–27 April 2007. With over 300 attendees from 18 countries and live transmission in high deWnition, the WRUS became the largest robotic surgery meeting ever. A comprehensive lecture program covered topics ranging from upper and lower tract oncological and non-oncological surgery through pediatric and urogynecologic robotic surgery to economics and reimbursement issues. A wide range of collaborating faculty, both national and international, brilliantly lectured on the application of robotics to urology. The faculty included the following: Thomas Ahlering, David Albala, Daniel Elliot, Randy Fagin, Inderbir Gill, David Lee, Raymond Leveillee, Robert Myers, Lawrence Ross, Joseph Smith, Michael Stifelman, Li Ming Su, Raju Thomas, Ash Tewari, Craig Zippe, Walter Artibani, Prokar Das Gupta, Tadashi Hatano, Ariel Kaufman, Rene Sotelo, S. R. Mohammad, Juan Palou, Thierry Piechaud, K. Rha, Michael Stoeckle, Mario Sung, Peter Wiklund, C. K. Yeung, Sun Yinghao and Phillip Stricker. Attendees viewed two live video feeds of robotic prostatectomy. A step-by-step detailed tour of the procedure, possible complications and peri-operative management was given by narrators Drs. Albala and Ahlering. Breakout sessions were led by an international expert panel of robotic surgeons who discussed diverse issues related to robotic surgical procedures, operative techniques and nuances using video-based learning. Here the participants had a close encounter with experienced surgeons, helping them overcome obstacles presented by the learning curve, and were able to share their experiences. Overall, urologists had the opportunity to receive updates on minimally invasive urologic surgery and robotic applications. They also watched live cases and received training before or after the symposium on one of the six robotic surgical systems available on campus for this event. The most important advantage of robotic technology is the ability to bridge the gap between open surgery and conventional laparoscopy, allowing more surgeons to immerse themselves daily in this surgical innovation. Future advances in surgical technique and instrumentation using robotics will surely allow this minimally invasive approach to expand into other subspecialties.
The Internet Rhetoric of the Ku Klux Klan: A Case Study in Web Site Community Building Run Amok

Many scholars have praised the Internet as a locale where positive community building takes place. Conversely, this study examines 23 KKK web sites as an exemplar of how groups may engage in community building of a most egregious sort. Through appeals to white masculinity and, on some web sites, segmented appeals to women and to youth and children, Klan web sites attempt to create community that is unified by its opposition to minority groups, particularly Jews. The angry style of Klan discourse, which is compatible with the rhetorical conventions of the Web, discourages dissenting points of view while inflaming potential supporters. Moreover, Klan rhetoric on the Web encourages odious political activity, including acts of violence, at the same time that Klan web sites disavow responsibility for the consequences of their messages.
Quantitative gas chromatographic analysis of mandelic acid enantiomers

Abstract A procedure was developed for the quantitative gas chromatographic (GC) analysis of mixtures of mandelic acid enantiomers. Past methods for the GC resolution of α-hydroxy acid enantiomers on optically active stationary phases are systematically reviewed, with special attention to mandelic acid, which is particularly prone to racemization during derivatization. Modification of an earlier procedure involving the conversions: mandelic acid → mandelyl chloride → N-propylmandelamide → O-trimethylsilyl-N-propylmandelamide finally permitted the preparation of O-trimethylsilyl-N-propylmandelamide on a macro scale with negligible racemization and allowed the precise GC analyses of mandelic acid enantiomers on a stainless-steel capillary column coated with N-docasanoyl-L-valine tert.-butylamide.
Kiss my Asperger's: turning the tables of knowledge

Since the early 1990s Asperger's syndrome (AS) has steadily gained media attention and public recognition to the point of being described as a cultural obsession. Using multi-method inquiry this paper: (1) challenges prevailing medicalised discourses of AS by including a satire of the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) [1994. Washington, DC: American Psychiatric Publishing] and a critique of advertisements created about AS and other related disabilities; (2) offers alternative interpretations within social, cultural, historical, and personal contexts; (3) foregrounds the experience and understanding of AS from individuals with AS; (4) contemplates the need for schools and colleges to become more receptive to neurodiversity, and to support students with AS. The author calls attention to the ongoing problematics of defining AS and illustrates how disability studies in education helps reframe AS in diverse ways, valuing the ontological and epistemological differences between ‘o...
Differential wavefront curvature sensor

In this paper, a wavefront curvature sensor is presented. This sensor is based on the measurements of the differentials of wavefront slopes, where the wavefront slope measurements can be achieved by a Shack-Hartmann sensor. A Shack-Hartmann sensor with three output collimated beams will be introduced with a lenslet array installed in each beam. By shifting two of the Shack-Hartmann grids in the x- and in the y- directions independently compared to the third grid, we can measure the slope differences and obtain the wavefront curvatures at each grid point. A wavefront reconstruction can be performed with the wavefront curvature measurements.
Identification of the Effect of Depression on Risky Sexual Behavior: Exploiting a Natural Experiment

Depression is pervasive in the US particularly among women. The costs in terms of direct medical costs and forgone earnings are substantial. This paper investigates an additional cost of depression. Using data from the National Longitudinal Survey of Adolescent Health, we use a unique instrument, the attacks of September 11, which have been linked to depression, to identify the effect of depression on risky sexual behaviors. We find that depressed women are more likely to be sexually active, to engage in oral sex and to have sex without a condom, even after controlling for a rich set of covariates.
Using the Nonlinear Kinematic Hardening Material Model of Chaboche for Elastic–Plastic Ratcheting Analysis

Two calibration processes are selected for determining the parameters of the Chaboche nonlinear kinematic hardening (NLK) material model for stainless steel. One process is manual that requires no outside software and the other follows a finite element software. The basis of the calibration is the monotonic stress-strain curve obtained from a tension specimen subjected to unidirectional loading. The Chaboche model is meant for elastic-plastic ratcheting analysis that is included in commonly used design codes. It is chosen because it is known that it can represent realistically the materials that are used for power plant components and pressure vessels. To test the calibration results, a pressurized cylindrical shell subjected to thermal cycling is selected as an example. It was found that, for the example, no more than four Chaboche components should be used in the determination of its parameters.Copyright © 2013 by ASME
A generalization of concavity for finite differences

Abstract The concept of concavity is generalized to discrete functions, u , satisfying the n th -order difference inequality, (−1) n − k Δ n u ( m ) ≥ 0, m = 0, 1,..., N and the homogeneous boundary conditions, u (0) = ... = u (k−1) = 0, u ( N + k + 1) = ... = u ( N + n ) = 0 for some k ∈ “1, ..., n − 1”. A piecewise polynomial is constructed which bounds u below. The piecewise polynomial is employed to obtain a positive lower bound on u ( m ) for m = k , ..., N + k , where the lower bound is proportional to the supremum of u . An analogous bound is obtained for a related Green's function.
Fault and fold growth of the Amenthes uplift: Implications for Late Noachian crustal rheology and heat flow on Mars

Abstract Determining the rheologic conditions that control growth of compressive structures on Mars is an elusive problem, one limited by the lack of seismologic and other data commonly available for comparable active uplifts on Earth. In some instances however, the geometry of faults on Mars that offset impact craters can be deduced from surface topography alone. With this aim, construction of a balanced and restorable structural cross section across the Late Noachian Amenthes uplift, or fault-related fold suggest it forms above a deeply penetrating blind thrust with a gently curved or listric geometry that flattens downward. Preferred structural solutions suggest the thrust dips between 41.5° and 56.1° at the surface and flattens into a horizontal decollement at depths of ∼ 33 – 48 km . The range of values for depth to detachment are greater than previous estimates for the Amenthes thrust based on elastic modeling for a range of planar thrust geometries. Using the inference that the decollement corresponds to the onset of plasticity in the crust, the depth to detachment is consistent with surface heat flow of 24 – 33 mW m − 2 based on average values for heat production and the temperature threshold for the transition from brittle faulting to ductile shear on Mars. This suggests the crust at Amenthes during the Late Noachian may be slightly cooler than previously thought, similar to recent estimates derived from studies of lithospheric strength.
Atomic force microscopy studies of admicellar polymerization polystyrene-modified amorphous silica

Atomic force microscopy was used to study polystyrene-modified silica surfaces produced by admicellar polymerization (polymerization of monomers solubilized in adsorbed surfactant aggregates). The goal was to examine changes in the location and nature of the formed polystyrene resulting from changes in the surfactant and monomer feed levels on precipitated silica. Normal tapping and phase-contrast modes in air were used to image the topography of the polystyrene-modified silica. Moderate-to-light force-tapping mode was used to differentiate between the silica surface and adsorbed water or polymer. The formed polystyrene exists primarily in the pores, with patches extending onto the exposed surface of the silica particles. At moderate tapping forces, darker phase regions were observed in the valleys and pores of the silica in both the modified and the unmodified samples. Upon higher magnification, the darker regions disappear on unmodified silicas, whereas polymer bands become evident on the modified silicas. At lower loadings of surfactant and monomer, the number and extent of polymer patches decreased, with polymer being found only in pores. The polystyrene patches observed inside the valleys of the amorphous silica varied from 1 to 10 nm in thickness. The structure of the polystyrene film formed on precipitated silica was found to be insensitive to the surfactant feed concentration. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 290–299, 2003
Magnetic field induced temperature changes in cryogenic liquids: N2, Ar, and He4

Abstract Measurements of magnetic field-induced changes in hydrostatic head corrections are reported for columns of liquid N 2 and Ar at their normal boiling points and for liquid He 4 between 2.15 and 4.2 K, in static magnetic fields to 15 T. The results for very high purity N 2 and Ar are in good agreement with calculations based on gas susceptibilities; diamagnetic coolings of − 32 ± 1.5 and − 64 ± 6 mK are observed for liquid N 2 and Ar respectively, at 15 T. However, O 2 contamination in amounts as small as 0.1 at % can drastically after the observed temperature changes. The measurements on He 4 above 3 K are also in good agreement with calculations based on the diamagnetic gas susceptibility. Below 3 K, the results deviate from the calculation in a paramagnetic direction; just above the λ-point, paramagnetic warnings of ∼ 10 mK are observed for a field of 15 T.
Effects of low temperatures on transmembrane potentials of single fibers of the rabbit atrium.

Lowering the temperature caused a fall in the diastolic membrane potential and action potential and an increase in the duration of the action potential in both pacemaker and nonpacemaker fibers of the rabbit atrium. Pacemaker fibers were the most resistant to cooling and continued to discharge at a temperature where all conducted action potentials and mechanical contractions had ceased. Acetylcholine (10-7 Gm./ml.) administered at a low temperature when only pacemaker fibers were discharging, elicited propagated action potentials and contractions. This effect was associated with an increase in diastolic membrane potential towards that existing at a temperature of 30 C.
Nearly degenerate multiwave mixing in quasi-equilibrium semiconductors

Abstract A theoretical analysis is presented of nearly degenerate multiwave mixing in quasi-equilibrium semiconductors, including many-body effects. Multiwave mixing coefficients are expressed in terms of the single-wave susceptibility and its derivative with respect to carrier density. The theory is illustrated with parameters appropriate for bulk GaAs including the many-body effects of bandgap renormalization and Coulomb enhancement.
Replacing Ti:sapphire regenerative ampliflers with an optical parametric chirped pulse amplifier

Summary form only given. Optical parametric chirped pulse amplification (OPCPA) offers several advantages when compared to regenerative chirped pulse amplification using Ti:sapphire or Cr:LiSAF. These advantages include low cumulative nonlinear phase (B-integral), greater wavelength flexibility, and high gain achieved without the use of gated electro-optic modulators and multipass amplification. High-energy OPCPA systems pumped by large aperture, low repetition rate glass laser systems have produced up to 0.5 J of amplified stretched pulses, subsequently recompressed to 300 fs. However, OPCPA using commercially available Q-switched pump lasers have, to date, only produced 600 /spl mu/J of amplified signal with a pump-to-signal conversion efficiency near 0.3 %. This low efficiency limits the attractiveness of OPCPA to facilities with high energy, shorter pulse pump lasers. We report chirped pulse amplification of broadband 1054 nm pulses to 31 mJ by single passing only 40 mm of gain material pumped by a commercial Q-switched laser, with a pump to signal conversion efficiency of 6%.
Systems approaches to coronavirus pathogenesis

Coronaviruses comprise a large group of emergent human and animal pathogens, including the highly pathogenic SARS-CoV and MERS-CoV strains that cause significant morbidity and mortality in infected individuals, especially the elderly. As emergent viruses may cause episodic outbreaks of disease over time, human samples are limited. Systems biology and genetic technologies maximize opportunities for identifying critical host and viral genetic factors that regulate susceptibility and virus-induced disease severity. These approaches provide discovery platforms that highlight and allow targeted confirmation of critical targets for prophylactics and therapeutics, especially critical in an outbreak setting. Although poorly understood, it has long been recognized that host regulation of virus-associated disease severity is multigenic. The advent of systems genetic and biology resources provides new opportunities for deconvoluting the complex genetic interactions and expression networks that regulate pathogenic or protective host response patterns following virus infection. Using SARS-CoV as a model, dynamic transcriptional network changes and disease-associated phenotypes have been identified in different genetic backgrounds, leading to the promise of population-wide discovery of the underpinnings of Coronavirus pathogenesis.
Thermal expansion of the hexagonal (4H) polytype of SiC

The principal axial coefficients of thermal expansion, alpha(11) and alpha(33), of the (4H) polytype of hexagonal alpha SiC have been determined by X-ray diffraction measurements in the temperature range 20-1000 C. Alpha(11) and alpha(33), derived from the lattice parameter measurements, were expressed as the second-order polynomials in temperature. Alpha(11) was found to be larger than alpha(33) over the entire temperature range, with a thermal expansion anisotropy factor A increasing from 0.04 at room temperature to 0.11 at 1000 C. The thermal expansion results for the (4H) structure were compared with previously published results for the cubic (3C) and the hexagonal (6H) SiC polytypes.
Intravenous Etomidate for Procedural Sedation in Emergency Department Patients

Abstract. Objective: To determine the safety and effectiveness of intravenous (IV) etomidate for the sedation of patients undergoing painful procedures in the emergency department (ED). Methods: A two-part feasibility study for ED patients receiving IV etomidate for painful ED procedures was undertaken. In the initial phase, a retrospective series of patients receiving etomidate for ED procedural sedation was considered. This phase served as the basis for a descriptive, prospective feasibility study of consecutive ED patients. During the second phase, patients were evaluated for complications related to IV etomidate sedation or the procedure performed. Immediately following the procedure, the physician was asked to complete a data collection sheet documenting the patient's etomidate dose, the number of doses required to complete the procedure, the analgesic used, the complications of the procedure, and the patient's procedural recall. Results: Intravenous etomidate was administered to nine patients during the initial study phase and 51 during the prospective, descriptive phase. Indications for sedation included dislocation reduction (25), cardioversion (7), fracture reduction (20), abscess incision and drainage (4), foreign body removal (3), and chest thoracostomy (1). Physicians used 0.1-mg/kg IV bolus etomidate. A mean of 1.6 doses of etomidate was used to complete procedures (range 1-3 doses). Of the 60 patients in both study groups, 59 (98%) achieved adequate sedation by physician's assessment. Procedural success was documented for 56 patients (93%). There were 12 complications reported: oxygen desaturation below 90% (5), myoclonus (4), vomiting (1), pain with injection (1), and a brief bradycardic episode (1). No patient required assistance with ventilation or endotracheal intubation. Conclusions: Intravenous etomidate can be administered safely and effectively to provide appropriate conscious sedation for short, painful ED procedures.
Butterfly bistability in grating coupled thin film waveguides

Abstract A new form of butterfly bistability was obtained in InSb waveguides for the throughput signal when two grating couplers were used, one for in-coupling and one for out-coupling. The nonlinearity was thermal and diffusive.
The role of angiotensin-converting enzyme in blood pressure control, renal function, and male fertility

Angiotensin-converting enzyme (ACE) is a zinc peptidase that plays a major role in the renin-angiotensin system. In mammals, the enzyme is present as two isozymes: a somatic form involved in blood-pressure regulation and a testis form of unknown function. Mice lacking ACE have been created and shown to have low systolic blood pressures and defects in renal development and function. These mice also have reduced male fertility, implicating the testis isozyme in reproductive function. (Trends Endocrinol Metab 1997;8:181-186). (c) 1997, Elsevier Science Inc.
A Dynamic Twist in the Tail

All planetary bodies with intrinsic magnetic fields or atmospheres possess very long magnetic tails ( 1 , 2 ). If they possess the same intrinsic magnetic field dipole orientation as Earth, then the northern half of the tail is composed of open magnetic fields oriented back toward the planet, and the southern half has the opposite orientation (see the figure, panel A). Sandwiched between these two lobes of the tail is a sheet of hot plasma derived from the solar wind and the atmospheres of the planet and its moons. The cross-tail electric current sheet that separates the sunward magnetic field in the northern lobe from the antisunward flux in the southern lobe lies at the center of the plasma sheet. The intrinsic magnetotails of Mercury and Earth store magnetic energy in their tail lobes and then rapidly convert it into plasma heating and high-speed jetting ( 3 , 4 ) through the process of magnetic reconnection ( 5 ). Venus and comets lack intrinsic magnetic fields, but magnetotails still form as a result of the heliospheric magnetic field lines carried by the solar wind draping about these bodies (see the figure, panel B). The Venera 9 and 10 and Pioneer Venus Orbiter missions to Venus found that the structure of its draped field magnetotail has many similarities to those of magnetized planets, but found no evidence for magnetic reconnection ( 6 , 7 ). Now, on page 567 of this issue, Zhang et al. ( 8 ) report observations of clear magnetic reconnection signatures in the Venus Express data, representing an unexpected discovery with important ramifications for our understanding of Venus.
Moral authority and the deliberative model

Gerald Gaus�s The Order of Public Reason: A Theory of Freedom and Morality in a Diverse and Bounded World is refreshingly ambitious. It seems to me that our field today is a little too eager to �[stay] on the surface, philosophically speaking� (Rawls 1999, p. 395; cf. 2005, p. 10). However, the scope of Gaus�s ambition complicates the critic�s task. When a philosophical work aims to present something as grand as a �theory of freedom and morality,� it seems plausible to think that the appropriate unit of analysis is the whole rather than any of its elements. This is especially so in the case of a book like Gaus�s, where the author�s philosophical acumen is well-matched to its objectives. Despite Gaus�s claims to be a fox (xiv), Numbers in parentheses without further citation information refer to Gaus�s The Order of Public Reason. The Order of Public Reason is a hedgehoggy work. A full-on assessment of Gaus�s book hence lies well beyond the scope of a single essay. My aims are consequently
Offshoring Jobs? Multinationals and U.S. Manufacturing Employment

Abstract Using firm-level data collected by the U.S. Bureau of Economic Analysis, we estimate the impact on U.S. manufacturing employment of changes in foreign affiliate wages. We show that the motive for offshoring and, consequently, the location of offshore activity, significantly affects the impact of offshoring on parent employment. In general, offshoring to low-wage countries substitutes for domestic employment. However, for firms that do significantly different tasks at home and abroad, foreign and domestic employment are complements. These offsetting effects may be combined to show that offshoring by U.S.-based multinationals is associated with a quantitatively small decline in manufacturing employment.
Nighttime intensivist staffing and the timing of death among ICU decedents: a retrospective cohort study

Intensive care units (ICUs) are increasingly adopting 24-hour intensivist physician staffing. Although nighttime intensivist staffing does not consistently reduce mortality, it may affect other outcomes such as the quality of end-of-life care. We conducted a retrospective cohort study of ICU decedents using the 2009–2010 Acute Physiology and Chronic Health Evaluation clinical information system linked to a survey of ICU staffing practices. We restricted the analysis to ICUs with high-intensity daytime staffing, in which the addition of nighttime staffing does not influence mortality. We used multivariable regression to assess the relationship between nighttime intensivist staffing and two separate outcomes potentially related to the quality of end-of-life care: time from ICU admission to death and death at night. Of 30,456 patients admitted to 27 high-intensity daytime staffed ICUs, 3,553 died in the hospital within 30 days. After adjustment for potential confounders, admission to an ICU with nighttime intensivist staffing was associated with a shorter duration between ICU admission and death (adjusted difference: –2.5 days, 95% CI -3.5 to -1.5, p-value < 0.001) and a decreased odds of nighttime death (adjusted odds ratio: 0.75, 95% CI 0.60 to 0.94, p-value 0.011) compared to admission to an ICU without nighttime intensivist staffing. Among ICU decedents, nighttime intensivist staffing is associated with reduced time between ICU admission and death and reduced odds of nighttime death.
Contentious Issues and World Politics: The Management of Territorial Claims in the Americas, 1816-1992

This article studies the management of territorial claims using an issue-based approach that reconceptualizes processes of interstate conflict and cooperation as reflecting contention over issues. Hypotheses on issue management techniques are tested using newly collected data from the Issue Correlates of War (ICOW) research project. Empirical analysis of territorial claims in the Western Hemisphere supports the general model, with issue salience and past issue interactions systematically affecting states' choices between peaceful and militarized techniques for managing or settling their contentious issues. In particular, action over territorial claims is most likely when more valuable territory is at stake, in the aftermath of militarized conflict, and when recent peaceful settlement attempts have failed. Third parties are more likely to become involved in nonbinding activities when the claim appears more threatening to regional or global stability, and submission of claims to binding third-party decisions is most likely between adversaries that have begun to build up a legacy of successful agreements. The article concludes with a discussion of directions for future research on territory and on other issues.
Dynamic transaction environment and market efficiency of electronic marketplaces

The objective of this paper is to model the online dynamic transaction environment, analyse the behaviour of buyers and sellers, and explore how online dynamic features affect market efficiency in electronic marketplaces. We find that under certain conditions the online dynamic environment can help increase the transaction probability, average used product quality level, market size, and total social welfare in electronic marketplaces. Using eBay's auction data, we empirically test the efficiency of electronic markets by comparing the auction process, outcome, and post-purchase evaluation between new products and used products. Our empirical findings suggest that the electronic marketplaces for used IT products such as Nintendo game consoles and TI calculators are as efficient as the new products. We contribute to the literature by demonstrating the dynamic electronic marketplace environment can improve market efficiency, and show empirical measurement results of market efficiency for electronic marketplaces.
π-Komplexe Der Übergangsmetalle II. Substituierte Di-Benzol-Chrom-Verbindungen

Di-benzol-chrom(I)- und Bis-(monodeuterium-benzol)-chrom(I)-Salze liesen sich ausgehend von Phenylmagnesiumbromid und Chrom(III)-chlorid isolieren. Belege fur deren Struktur und fur den Reaktionsmechanismus werden gegeben. Ferner wird die Bildung der im Verlaufe dieser Umsetzung ebenfalls erhaltenen Benzol-diphenyl-, (Monodeuterium-benzol)-diphenyl- und Bis-diphenyl-chrom-(I)-Salze diskutiert.
Sickle cell disease: Current activities, public health implications, and future directions

Sickle cell disease (SCD) is a genetic blood disorder caused by abnormal hemoglobin that damages and deforms red blood cells (RBCs). The abnormal red cells break down, causing anemia, and obstruct blood vessels, leading to recurrent episodes of severe pain and multiorgan ischemic damage. SCD affects millions of people throughout the world and is particularly common among people whose ancestors come from sub-Saharan Africa. Sickle cell trait (SCT) is an inherited condition in which both normal hemoglobin and sickle hemoglobin are produced in the RBCs. SCT is not a type of sickle cell disease. People with SCT are generally healthy. In SCD, clinical severity varies, ranging from mild and sometimes asymptomatic states to severe symptoms requiring hospitalization. Symptomatic treatments exist, but there is no cure for SCD. Although there has been extensive clinical and basic science research in SCD, many public health issues, such as blood safety surveillance, compliance with immunizations, follow-up of newborns with positive screening tests, stroke prevention, pregnancy complications, pain prevention, quality of life, and thrombosis, in people with SCT remain unaddressed. Currently, efforts are under way to strengthen SCD-related activities within the Centers for Disease Control and Prevention (CDC). To date, several activities are being or have been conducted by centers within CDC, including quality assurance of newborn screening tests for SCD, morbidity and mortality studies, genetic studies, and studies focusing on the protective effects of SCT for malaria. This paper discusses the public health implications of SCD, summarizes SCD-related activities within CDC, and points to future directions that the agency can take to begin to address some of these issues.