cssi/SciSciGPT-SciSciNet huggingface dataset:
Graphene microsheets enter cells through spontaneous membrane penetration at edge asperities and corner sites

Understanding and controlling the interaction of graphene-based materials with cell membranes is key to the development of graphene-enabled biomedical technologies and to the management of graphene health and safety issues. Very little is known about the fundamental behavior of cell membranes exposed to ultrathin 2D synthetic materials. Here we investigate the interactions of graphene and few-layer graphene (FLG) microsheets with three cell types and with model lipid bilayers by combining coarse-grained molecular dynamics (MD), all-atom MD, analytical modeling, confocal fluorescence imaging, and electron microscopic imaging. The imaging experiments show edge-first uptake and complete internalization for a range of FLG samples of 0.5- to 10-μm lateral dimension. In contrast, the simulations show large energy barriers relative to kBT for membrane penetration by model graphene or FLG microsheets of similar size. More detailed simulations resolve this paradox by showing that entry is initiated at corners or asperities that are abundant along the irregular edges of fabricated graphene materials. Local piercing by these sharp protrusions initiates membrane propagation along the extended graphene edge and thus avoids the high energy barrier calculated in simple idealized MD simulations. We propose that this mechanism allows cellular uptake of even large multilayer sheets of micrometer-scale lateral dimension, which is consistent with our multimodal bioimaging results for primary human keratinocytes, human lung epithelial cells, and murine macrophages.
Changes in the 300-mb North Circumpolar Vortex, 1963–2001

Abstract The mean monthly polar stereographic map analyses of the Free University of Berlin terminated at the end of 2001. This paper summarizes the changes in size of the 300-mb north circumpolar vortex, and quadrants, for the full period of record, 1963–2001, where the size has been defined by planimetering the area poleward of contours in the jet stream core. A contracted vortex has tended to be a deep vortex in winter but a shallow vortex in summer. During 1963–2001 there was a statistically significant decrease in vortex size of 1.5% per decade, the decrease in size of Western Hemisphere quadrants being twice that of Eastern Hemisphere quadrants. A significant increase in Arctic Oscillation (AO) index accompanies the significant decrease in vortex size, but since the vortex contracts appreciably in all four seasons, whereas the positive trend in the AO index is mainly in winter, the vortex cannot serve as a proxy for the AO index. The evidence for vortex contraction at the time of the 1976–77 regime ...
A homotopy algorithm for approximating geometric distributions by integrable systems

In the geometric theory of nonlinear control systems, the notion of a distribution and the dual notion of codistribution play a central role. Many results in nonlinear control theory require certain distributions to be integrable. Distributions (and codistributions) are not generically integrable and, moreover, the integrability property is not likely to persist under small perturbations of the system. Therefore, it is natural to consider the problem of approximating a given codistribution by an integrable codistribution, and to determine to what extent such an approximation may be used for obtaining approximate solutions to various problems in control theory. In this note, we concentrate on the purely mathematical problem of approximating a given codistribution by an integrable codistribution. We present an algorithm for approximating an m-dimensional nonintegrable codistribution by an integrable one using a homotopy approach. The method yields an approximating codistribution that agrees with the original codistribution on an m-dimensional submanifold E_0 of R^n.
PROGNOSTIC ROLE OF HEMOCONCENTRATION IN PATIENTS HOSPITALIZED FOR HEART FAILURE WITH REDUCED EJECTION FRACTION: AN ANALYSIS OF THE EVEREST TRIAL

results: Hemoconcentration correlated with in-hospital increases in serum creatinine and urea nitrogen levels and in-hospital decreases in glomerular iltration rate and body weight. Over median follow-up of 9.9 months, every 5% increase of in-hospital hematocrit change was associated with a decreased risk of all-cause death (Hazard Ratio [HR] = 0.79, 95% Conidence Interval [CI]0.68-0.90) and the composite of cardiovascular mortality or heart failure (HF) hospitalization (HR = 0.87, 95% CI 0.78-0.97).
Logical testing for rule-base management

We present a procedure to logically reduce simple implications that comprise the rule-base of an expert system. Our method uses topological sorting on a digraph representation that detects logical inconsistency and circular reasoning in linear-time. Then, the sort order provides an efficient method to detect and eliminate forced values and redundant rules. We consider additional diagnostic aids for the rule-base manager, notably how to range the number of propositions that could be true and how to consolodate the rule-base. We than show how the simple case may be extended to logically test a general rule-base with a decomposition principle.
Reactions of Uranium With the Platinide Elements. I. The Uranium-Ruthenium System.

The phase diagram of the uranium-ruthenium system was constructed from data obtained by thermal analysis, metallographic examination, and x-ray diffraction. The system is characterized by five intermetallic compounds: U2Ru, formed peritectically near 937 °C; "URu," melting congruently near 1158 °C; U3Ru4, formed peritectically near 1163 °C; U3Ru5, formed peritectically near 1182 °C; and URu3, formed peritectically at about 1850 °C. "URu" has a solid-state transition at about 795 °C. One eutectic occurs near 886 °C and 18.5 atomic percent (a/o) ruthenium, and a second at about 1148 °C and 49 a/o ruthenium. The maximum solid solubilities are about 7.5 a/o ruthenium in uranium and near 1.3 a/o uranium in ruthenium. Ruthenium lowers the gamma-uranium transformation to near 691 °C and the beta-transformation to near 625 °C.
Model-derived estimates of groundwater mean ages, recharge rates, effective porosities and storage in a limestone aquifer

Abstract The Edwards aquifer of south-central Texas, U.S.A., a highly fractured and faulted group of limestone formations, is the major water supply for the San Antonio area. A discrete-state compartment (DSC) model or mixing-cell model, based upon the conservation of environmental tritium within the aquifer, was used to obtain estimates of groundwater mean ages, recharge, effective porosities and storage in the Edwards aquifer in the vicinity of San Antonio, Texas. The model was calibrated and validated with the spatial and temporal (1953–1971) distributions of environmental 3H (tritium) in the groundwater. The final model consisted of 34 cells; eight of these cells represented the unconfined portion of the Edwards aquifer in the vicinity of the Balcones fault zone, an area where recharge occurs via streamflow infiltration and direct infiltration of precipitation. The model confirmed previous analyses of flow in the Edwards system: generally parallel to the Balcones fault zone with restricted flow perpendicular to this zone. Groundwater mean ages ranged from 16 to over 130 yr. The storage volume of the confined portion of the Edwards aquifer is ∼ 30.9 km3, which corresponds to an average effective porosity of 4.8% (range: 1.9–8%). The average annual recharge to the Edwards aquifer during the period 1953–1971 was 0.614 km3. The study demonstrated that discrete-state compartment models calibrated and validated with environmental tritium distributions can yield valuable hydrogeologic information that is difficult or expensive to obtain using traditional techniques. The approach used in the study is particularly suited to limestone aquifers, which are normally extremely difficult to analyze with traditional methods.
Endogenous ADP prevents PGE1-induced tyrosine dephosphorylation of focal adhesion kinase in thrombin-activated platelets

Abstract Prostaglandin E 1 (PGE 1 ) inhibits tyrosine phosphorylation induced by low thrombin concentration (0.05 U/ml), but this is overcome by a high thrombin (2.0 U/ml) concentration. Thromboxane A 2 and ADP are endogenous platelet agonists released during platelet activation which potentiate platelet responses. We investigated how these endogenous agonists influenced the effects of PGE 1 on thrombin (2.0 U/ml)-induced tyrosine phosphorylation by removing released ADP with apyrase (2.0 U/ml) and by inhibiting thromboxane A 2 synthesis with indomethacin (1 μM). Adding PGE 1 (1 μM) before thrombin in apyrase/indomethacin(A/I)-treated platelets selectively prevented thrombin-induced tyrosine phosphorylation of a 117 kDa protein while other substrates were not affected. This selective effect was evident only in the presence of apyrase and was not dependent on indomethacin. Addition of PGE 1 to A/I-treated platelets after thrombin also caused selective tyrosine dephosphorylation of the 117 kDa protein. Conditions which prevented thrombin-induced 117 kDa protein tyrosine phosphorylation also decreased fibrinogen binding to platelets. The 117 kDa protein was identified as the focal adhesion kinase (FAK) by immunoprecipitation with a monoclonal antibody to FAK and by absence of its tyrosine phosphorylation in the presence of RGDS peptide which inhibits fibrinogen binding and platelet aggregation. Thus, released endogenous ADP selectively prevents PGE 1 -mediated tyrosine dephosphorylation of platelet FAK most likely by stabilizing fibrinogen binding to platelets.
Tomographic full-waveform inversion (TFWI) by combining FWI and wave-equation migration velocity analysis

Convergence of full waveform inversion can be improved by extending the velocity model along either the subsurface-offset axis or the time-lag axis. The extension of the velocity model along the time-lag axis enables us to linearly model large time shifts caused by velocity perturbations. The extension is based on a new linearization of the scalar wave equation where the extended-velocity perturbation is convolved in time with the Laplacian of the background wavefield. This linearization is accurate for both reflected events and transmitted events and, in particular, for diving waves recorded at large offsets. The modeling capabilities of the proposed linearization enable the simultaneous inversion of reflections and diving waves even when the starting velocity model is far from being accurate. We solve the resulting optimization problem with a nested algorithm. The inner iterations are based on the proposed linearization and on a mixing of scales between the short- and long-wavelength components of the v...
Double-blind study of intravenous propafenone for paroxysmal supraventricular reentrant tachycardia.

Propafenone was administered during electrophysiologic testing to determine its efficacy and safety for terminating and preventing reinduction of paroxysmal supraventricular reentrant tachycardia. Four men and 10 women (mean age 50 years, range 28 to 69) were studied. Five patients had Wolff-Parkinson-White syndrome with orthodromic atrioventricular (AV) reentrant tachycardia, three had a concealed accessory pathway with AV reentrant tachycardia and six had tachycardia due to reentry within the AV node. In the five patients with Wolff-Parkinson-White syndrome, propafenone terminated reentrant tachycardia in three (the tachycardia was reinducible in one) and had no effect in two. In the three patients with a concealed accessory pathway, propafenone terminated reentrant tachycardia in all three and prevented reinduction of the tachycardia in two. In the six patients with tachycardia due to reentry within the AV node, propafenone terminated and prevented reinduction of reentrant tachycardia. Propafenone had no effect on blood pressure, heart rate, PA interval, AV node refractoriness or rate of reentrant tachycardia. Propafenone significantly (p Of the nine patients receiving long-term oral propafenone therapy, eight had a reduction of at least 90% in reentrant tachycardia during a mean follow-up period of 14.5 months (range 11 to 22); all eight patients had had noninducible reentrant tachycardia after intravenous propafenone. One patient had increased frequency of reentrant tachycardia; this patient had had inducible reentrant tachycardia after intravenous propafenone. In conclusion, intravenously administered propafenone terminated reentrant tachycardia in 85% of patients and prevented reinduction in 71%, with no adverse hemodynamic effects.
Analysis of saltwater upconing beneath a pumping well

Abstract Aquifer systems that contain freshwater and saltwater are usually stratified, with the more dense saltwater underlying the freshwater. A groundwater well discharging from the freshwater zone causes the saltwater to move upwards towards the well. This phenomenon is known as saltwater upconing. Two methods of analysis, the sharp-interface method and the fluid-density-dependent solute-transport method, are used to simulate saltwater upconing. Numerical experiments including comparisons of the two methods indicate: (1) for low to moderate pumpages the 50% isochlor and sharp interface correlate well; (2) the well can discharge significant concentrations of saltwater, even though a stable cone (according to the sharp-interface method) exists below the well screen; (3) an almost linear relationship exists between the well discharge rate and the concentration of the discharge at low pumping rates that maintain a stable cone; and (4) upconing is sensitive to transverse dispersivity, whereas it is insensitive to longitudinal dispersivity. A simulation of upconing at Test Site No. 4, Truro, Cape Cod, Massachusetts, indicates that the appropriate field value of transverse dispersivity is very small. This supports the validity of the sharp-interface assumption for analyzing the behavior of systems with thin saltwater-freshwater transition zones.
Evaluation of WHO immunologic criteria for treatment failure: implications for detection of virologic failure, evolution of drug resistance and choice of second-line therapy in India

Introduction: Routine HIV viral load (VL) testing is not available in India. We compared test performance characteristics of immunologic failure (IF) against the gold standard of virologic failure (VF), examined evolution of drug resistance among those who stayed on a failing regimen because they did not meet criteria for IF and assessed implications for second-line therapy. Methods: Participants on first-line highly active antiretroviral therapy (HAART) in Bangalore, India, were monitored for 24 months at six-month intervals, with CD4 count, VL and genotype, if VL >1000 copies/ml. Standard WHO criteria were used to define IF; VF was defined as having two consecutive VL>1000 copies/ml or one VL >10,000 copies/ml. Resistance was assessed using standard International AIDS Society-USA (IAS-USA) recommendations. Results: Of 522 participants (67.6% male, mean age of 37.5; 85.1% on nevirapine-based and 40.4% on d4T-containing regimens), 57 (10.9%) had VF, 38 (7.3%) had IF and 13 (2.5%) had both VF and IF. The sensitivity of immunologic criteria to detect VF was 22.8%, specificity was 94.6% and positive predictive value was 34.2%. Forty-four participants with VF only continued on their failing first-line regimen; by the end of the study period, 90.9% had M184V, 63.6% had thymidine analogue mutations (TAMs), 34.1% had resistance to tenofovir, and 63.6% had resistance to etravirine. Conclusions: WHO IF criteria have low sensitivity for detecting VF, and the presence of IF poorly predicts VF. Relying on CD4 counts leads to unnecessary switches to second-line HAART and continuation of failing regimens, jeopardizing future therapeutic options. Universal access to VL monitoring would avoid costly switches to second-line HAART and preserve future treatment options. Keywords: virologic failure; immunologic failure; WHO criteria; genotype; resistance; India; resource-limited settings. Citation: Vallabhaneni S et al. Journal of the International AIDS Society 2013, 16 :18449 http://www.jiasociety.org/index.php/jias/article/view/18449 | http://dx.doi.org/10.7448/IAS.16.1.18449
Impaired cognitive performance in subjects with methamphetamine dependence during exposure to neutral versus methamphetamine-related cues

Background: Chronic methamphetamine abuse is associated with cognitive deficits that may impede treatment in methamphetamine-dependent patients. Exposure to methamphetamine-related cues can elicit intense craving in chronic users of the drug, but the effects of exposure to drug cues on cognitive performance in these individuals are unknown. Objectives: This study assessed whether exposure to methamphetamine-related visual cues can elicit craving and/or alter dual task cognitive performance in 30 methamphetamine-dependent subjects and 30 control subjects in the laboratory. Methods: Reaction time, response errors, and inhibition errors were assessed on an auditory Go–No Go task performed by adult participants (total N = 60) while watching neutral versus methamphetamine-related video cues. Craving was assessed with the Within-Session Rating Scale modified for methamphetamine-dependent subjects. Results: Exposure to methamphetamine-related cues elicited craving only in methamphetamine-dependent subjects. Even...
The Phenomenology of Telephone Space

The temporally immediate transcendence of space through the use of the telephone creates a bi-localized space of interaction. Unique structures of spatial experience are constituted through the intending of spatial sectors in telephonic conversation. In the first section of this paper, six eidetic variations are presented that establish the various ways in which environmental sectors are intended through the intersubjective space of the telephonic medium. The telos of these descriptions is to characterize changes in social praxis that have been made available with the inclusion in the life-world of the telephone as a typical tool. In the second section, a constitutive analysis is undertaken in order to investigate how empty intentions are brought to fulfillment in the telephonic conversational thematizations of environmental sectors. Telephone space involves a modified we-relationship through which meaning-intentions are intersubjectively synthesized, yet from bi-local environmental standpoints. The intersubjective achievements concerning projects grounded within the immediacy of telephonic transcendence create a unique structure of meaning-fulfillment.
DISTORTION COORDINATE FOR NONRIGID FIVE- COORDINATED GERMANIUM. SYNTHESIS AND MOLECULAR STRUCTURE OF SPIROCYCLIC ANIONIC METHYLGERMANATES VARYING IN RING COMPOSITION′

Abstract Reaction of an organogermanium trichloride with a catechol or thiocatechol derivative in the presence of triethylamine, followed by a metathetical exchange, led to the isolation of the Et,N′ salts of the five-coordinated spirocyclic germanates [(C,H,0,),GeMe][Et,N] (1), [(MeC,H3S2_)2GeMe][Et,N] (2), [(C,CI,O,), GeMe][Et,N] (3), and [(C,H,S,), GePh][Et,N] (4). X-ray analysis showed that the geometry of 1 is close to a trigonal bipyramid, 2 is displaced about one-third toward the rectangular pyramid, and 3 is close to the rectangular pyramid. The low structural displacement for 1 is attributed to lattice effects. The structures of 2 and 3 are discussed in terms of ligand effects, the insertion of ring sulfur atoms in 2, and the electron-withdrawing effect of chlorine ring atoms in 3. The structures of these and related anionic germanates follow the local C2, constraint of the Berry pseudorotational coordinate with a trans basal angle, 0, for the “limiting” RP of 150.1°, similar to that for other ma...
Machining operations and associated machining fluid exposures: issues for health and safety intervention in manufacturing.

The outline for a workshop discussion of intervention research in manufacturing industry is presented. The example used is the control of machining fluid exposures, a widespread exposure that is associated with risk of cancer, pulmonary disease, dermatitis, and several types of accident-related injuries. Relevant technical considerations for conducting intervention research include the selection of machining fluid for different machining purposes, the management of fluids in use, and the selection and maintenance of environmental controls. Equally important are nontechnical considerations including the need for creating labor-management health and safety committees, the use of administrative rules on job performance for both workers and management, and training on the role of individuals from either group in exposure control. Clarity concerning the objectives for an intervention study and plans for clear means to evaluate study outcomes is critical. Important study variables will include site selection, plant size, plant demographics, the involvement of workers in the study, a willing management, and concern for susceptible workers. © 1996 Wiley-Liss, Inc.
Rôle of Adrenals in Blood Pressure Reaction to Anoxia During Insulin Hypoglycemia

SummaryThe blood pressure rise which increases in response to the inhalation of 6% oxygen when the blood sugar falls during the course of insulin hypoglycemia is not influenced by bilateral ligation of the adrenals. It is, therefore, concluded that under the conditions of our experiments an increased secretion of adrenin does not account for the greatly increased blood pressure response. The latter seems to be due to increased sympathetic discharges only.
Chemical constituents of Cocculus carolinus D. C. (Menispermaceae)

A phytochemical investigation of an ethanolic extract of the stems and leaves of Cocculus carolinus D.C (Menispermaceae) resulted in the isolation and characterization of six compounds: the cyclitols, (+)‐quercitol and (−)‐viburnitol; the lactone, loliolide; and the alkaloids, sinoacutine, magnoflorine, and palmatine. In each case, the identity of the constituent was confirmed by spectral and mixed melting‐point comparison with authentic samples.
THE INFLUENCE OF RELATIONAL DEMOGRAPHY ON PANEL INTERVIEW RATINGS: A FIELD EXPERIMENT

The influence of relational demography (assessor race, candidate race, and the racial composition of rating panels) was examined in a structured interview setting. Twenty assessors (10 White and 10 Black) comprising five, 4-person panels of all possible racial compositions, evaluated videotaped responses of police officers participating in a promotion process. Each panel rated the same 73 (36 White and 37 Black) candidates’ responses to a complex, structured interview question. An examination of mean overall ratings revealed a same race bias and a significant difference between panels based upon the relational demography of the interview panel; nevertheless, the size of these effects was small. Net reconciliation (i.e., between initial and final scores) differed significantly between minority and majority panel conditions for only Black assessors and, again, the effects here were very small. The practical implications of these findings are discussed.
Somatostatin 281–14 immunoreactivity in primary afferent neurons of the rat spinal cord

Abstract Somatostatin 28 1–14 immunoreactivity is present in dorsal root ganglion cells and in the superficial laminae of the spinal cord in the rat. The distribution of somatostatin 28 1–14 immunoreactive varicosities in the dorsal horn corresponds well to the distribution of somatostatin 14 immunoreactive elements. Some dorsal root ganglion cells exhibit both somatostatin 14 and somatostatin 28 1–14 immunoreactivities.
Multistable Fabry-Perot resonator with an active Sagnac interferometer as its retro-reflector

Abstract Multistable operations of an active Fabry-Perot (FP) resonator with an active Sagnac interferometer as its optically pumped variable reflectance retro-reflector (SIFP), is analyzed. Intensity-dependent transmission (reflection) curves are derived. The corresponding multistable operation is also indicated. By adjusting the SIFP parameters, it can be configured to be either an optical limiter, or an amplifier, or a logic or a memory element.
Cones and error bounds for linear iterations

Consider an ordered Banach space with a cone of positive elementsK and a norm ∥·∥. Let [a,b] denote an order-interval; under mild conditions, ifx*∈[a,b] then $$||x * - \tfrac{1}{2}(a + b)|| \leqslant \tfrac{1}{2}||b - a||.$$ This inequality is used to generate error bounds in norm, which provide on-line exit criteria, for iterations of the type $$x_r = Ax_{r - 1} + a,A = A^ + + A^ - ,$$ whereA+ andA− are bounded linear operators, withA+K ⊂K andA−K ⊂ −K. Under certain conditions, the error bounds have the form $$\begin{gathered} ||x * - x_r || \leqslant ||y_r ||,y_r = (A^ + - A^ - )y_{r - 1} , \hfill \\ ||x * - x_r || \leqslant \alpha ||\nabla x_r ||, \hfill \\ ||x * - \tfrac{1}{2}(x_r + x_{r - 1} )|| \leqslant \tfrac{1}{2}||\nabla x_r ||. \hfill \\ \end{gathered} $$ These bounds can be used on iterative methods which result from proper splittings of rectangular matrices. Specific applications with respect to certain polyhedral cones are given to the classical Jacobi and Gauss-Seidel splittings.
Hybrid Solid State/Fluidic Cooling for Hot Spot Removal

In this article we describe a novel cooling scheme utilizing a combination of fluidic (single-phase convection and phase change) and solid-state (superlattice cooler) techniques to simultaneously remove high background heat fluxes (∼100 W/cm2) over the entire chip and dissipate ultra high heat fluxes (∼0.5–1 kW/cm2) from multiple localized hot spots. This article focuses on the conceptual design to assess the feasibility of the proposed cooling scheme.
Absolute obligations and ordered worlds

Les A. visent a demontrer qu'il existe une classe importante de systemes normatifs dont le contenu ne peut pas etre represente avec precision par la classification de D.Lewis des mondes 3-D, et plus particulierement des systemes normatifs qui peuvent generer plus d'une obligation absolute logiquement independante
A daring reconnaissance of red territory

It used to be, not so long ago, that philosophers—and a few ‘humanistic’ psychologists—were the only academics who could bear to talk about consciousness in public. Then about the time the first President Bush declared the 1990s the Decade of the Brain—I doubt there is a causal connection—scientists who up till then would never have been caught dead writing about the mysteries of consciousness changed their minds and started holding forth with abandon. Somewhere in the collective psyche a dam broke, releasing a flood of books and articles by distinguished scientists as well as philosophers about how (or whether) the brain could be the seat of consciousness. Many of the literally hundreds of books that have appeared have a single idea about the key to solving the mystery, and perhaps the stampede was provoked by their authors' sense that we were entering the end game, and if they wanted to share in the glory, they had better get their pet idea into the limelight as soon as possible. This hunch that a single flip in everybody's thinking will unlock the secrets is not implausible. The stubborn intractability of the problem of consciousness could well be because some assumption that everybody finds too obvious to consider denying is just false. If there were no such complacently shared mistake, would not we have solved the problem by now? The solution is bound to be deeply counterintuitive at first blush, and Nicholas Humphrey is not alone in having a candidate for an outrageous reversal that will do the trick. He is unique, however, in his combination of audacity and circumspection, an intellectual tightrope walker, proposing hypotheses that seem utterly unpromising—even silly mistakes—at first, and then reassuring the reader by acknowledging their dubiety, and promising a vista that will soon make sense of them …
Age at first drink and the first incidence of adult-onset DSM-IV alcohol use disorders.

Background Existing studies of the association between age at first drink (AFD) and the risk of alcohol use disorders (AUD) suffer from inconsistent levels of control and designs that may inflate associations by failure to control for duration of exposure to risk.
Investigating the Molecular Architecture of Hyperbranched Polymers

Hyperbranched polymers constitute a unique class of branched macromolecules, where structural complexity is complemented by relative ease of synthesis. The increasing interest in the study of these materials is due to their distinctive properties, inherently tied to their complex molecular architecture, and is augmented by the continual growth of applications like catalysis, viscosity modifiers, and sensors. We report a structural model for HBPs based on fractal scaling of both mass and connectivity. This model is shown to be of use in understanding small angle scattering data, especially in comparison with nuclear magnetic resonance spectroscopy for structural characterization.
Optical coherence tomography imaging of collagenous tissue microstructure

The engineering of new biomaterials requires an in-depth understanding of the structure and function of the native tissues. Optical coherence tomography (OCT) is a non-destructive technique that allows the visualization of the microstructure of biological tissues. The aim of this study was to determine if OCT could be used to identify geometric properties of tendons such as crimp pattern. Freshly harvested tendon tissue was imaged with OCT during the application of incremental axial strain. Loads were simultaneously recorded during imaging. Results revealed that birefringent banding perpendicular to the collagen fiber axis could be visualized and measured. This crimp banding disappeared at a very low strain. Birefringent banding parallel to the collagen fiber axis was also seen and it was observed that the number of parallel bands increased as strain increased. Stress-strain data was calculated and found to lie within the expected range. These results indicate that OCT may prove to be a useful tool for the non-destructive analysis of tissue microstructure.
Is the UK preparing for “war”? Military metaphors, personal carbon allowances, and consumption rationing in historical perspective

Metaphors are essential devices for fostering collective understanding and forging political commitment across diverse constituencies. Due to the ineffectualness of prevailing linguistic representations of climate change, discursive entrepreneurs have begun to invoke over the last few years new imagery that frames the challenge as tantamount to a protracted state of armed hostility. This process of rhetorical militarization has been most prominent in the UK and it is subsequently creating opportunities for policy makers to propose greenhouse gas-reduction strategies that are reminiscent of wartime austerity programs. A particular approach that has attracted considerable interest is consumer regulation involving the imposition of annual quotas on personal carbon emissions. This idea is best understood as a variant of the comprehensive civilian rationing programs that were deployed during and after World War II. Because any eventual scheme to reduce greenhouse gas production at the individual level will require consummate public legitimacy, this historical experience can serve as a useful reference point for the design of contemporary interventions. To this end, the discussion highlights the methods that the British government used to sustain compliance with the war and postwar consumption control regimes. Of special interest is the role that black market trading and other illicit forms of commerce played during these periods. The conclusion reflects on the status of consumerism in contemporary lifestyles, considers the risks of political interference with consumer prerogatives, and draws some insights from this earlier experience with rationing
Up-expression of NapA and other oxidative stress proteins is a compensatory response to loss of major Helicobacter pylori stress resistance factors

Twenty-six Helicobacter pylori targeted mutant strains with deficiencies in oxidative stress combating proteins, including 12 double mutant strains were analyzed via physiological and proteomic approaches to distinguish the major expression changes caused by the mutations. Mutations were introduced into both a MtzS and a MtzR strain background. Most of the mutations caused increased growth sensitivity of the strains to oxygen, and they all exhibited clear compensatory up-expression of oxidative stress resistance proteins enabling survival of the bacterium. The most frequent up-expressed oxidative stress resistance factor (observed in 16 of the mutants) was the iron-sequestering protein NapA, linking iron sequestration with oxidative stress resistance. The up-expression of individual proteins in mutants ranged from 2 to 10 fold that of the wild type strain, even when incubated in a low O2 environment. For example, a considerably higher level of catalase expression (4 fold of that in the wild-type strain) w...
Infrared Dichroism and Surface Conformational Dynamics of Adsorbed Poly(dimethylsiloxane)

We examined polymer conformations at a strongly adsorbing solid surface and their evolution with elapsed time during the adsorption process. Poly(dimethylsiloxane) (PDMS: Mw = 118 000; Mw/Mn = 1.1...
Growth of AgGaSe2 for infrared applications

Abstract High quality crystals of AgGaSe2 suitable for IR applications have been grown successfully utilizing the Bridgman technique. Boule sizes were typically 13 mm diameter by 6 cm long, but due to polycrystallinity and cracking, only half the boule was of high optical quality. The slow growth rates required for optical quality, and compositional variations along the boule, prompted phase equilibrium studies in the Ag-Ga-Se ternary system. DTA, microstructural analysis and electron microprobe studies established that whilst the compound melts congruently at the stoichiometric composition, the system is extremely sensitive to deficiencies in Se. Both macroscopic second phase regions and micron-size IR scattering centers have been observed in materials grown from Se-deficient melts.
Fullerene Grafted Photoacid Generator(PAG) Bound Polymer Resists

Two polymeric fullerene derivatives and corresponding fullerene grafted, PAG bound polymer resists (HS-EM-HM/Fulle-PAG) based on hydroxystyrene (HS), 2-ethyl-2-adamantyl methacrylate (EM), 3-hydroxy-1-admantyl methacrylate (HM) were prepared and characterized. The preliminary lithographic performance of these polymers were conducted with a contact printer, e-beam, and structure-function relationships were also studied. The results demonstrated that the thermostability and glass transition temperatures increased, but sensitivity and resolution decreased. Further investigations about microstructure modification, composition effect, exposure conditions on the lithographic properties will be carried out.
Carbon dynamics subsequent to establishment of switchgrass

Abstract It is necessary to develop new, clean and renewable biofuels to mitigate the greenhouse effect and reduce dependence on nonrenewable fossil fuels. Switchgrass ( Panicum virgatum L.) has been chosen by the US Department of Energy as its model herbaceous energy crop in the Southeast due to high yields, low production costs, economic benefits, and little competition from existing enterprises. However, knowledge of its influence on soil carbon (C) dynamics is limited, as no systematic study of soil C dynamics in switchgrass culture has been conducted. Our objective was to determine C dynamics subsequent to switchgrass establishment and the impact of cultural practices (row spacing and harvest frequency) on C biogeochemical characteristics in a sandy loam soil (Typic Paleudult) and a clay loam soil (Typic Hapludult). Results indicated that soil C characteristics changed over time after switchgrass establishment. Carbon mineralization, microbial biomass C, C turnover, and % microbial biomass C in organic C was generally higher approximately 2 years after switchgrass planting than after its initial establishment in a sandy loam soil. Specifically, C mineralization increased by 112 and 254% at depths of 0–15 cm and 15-30 cm, respectively; microbial biomass C increased by 168% in the top 15 cm of soil; and C turnover increased by 116 and 255% at 0-15 cm and 15–30 cm, respectively. Microbial biomass comprised 0.76±0.09% and 0.75±0.19% of soil organic C in 0–15 cm and 15–30 cm depths, respectively, of sandy loam soil, while it made up 1.37±0.22% and 1.11±0.19% of soil organic C in the same soil depths in clay loam soil. Harvesting once resulted in more C turnover than harvesting twice in the sandy loam soil. Linear regression between soil C characteristics and switchgrass root weight, root C, and root nitrogen (N) returned to soil support the conclusion that soil C accumulation is positively related to root input. It appears that switchgrass establishment may have dual benefits as a source of renewable energy and as a means of improving soil quality. However, longer periods of study will be required to elucidate substantial gains in soil quality owing to switchgrass culture.
An analysis of the factors affecting the supply and demand for teacher quality

This paper analyzes the factors that have influenced the supply and demand for teacher quality in Arkansas' public schools. The paper relies on results from a basic skills test, given to all Arkansas public school teachers in 1985, to measure teacher quality. Relying on these data, a simultaneous equation model is constructed to disentangle the supply and demand forces that determined the level of teacher quality in a county. Price and income elasticities are also calculated and compared to elasticity estimates found in other studies.
Invited Review Article: Current State of Research on Biological Effects of Terahertz Radiation

Terahertz (THz) imaging and sensing technologies are increasingly being used in a host of medical, military, and security applications. For example, THz systems are now being tested at international airports for security screening purposes, at major medical centers for cancer and burn diagnosis, and at border patrol checkpoints for identification of concealed explosives, drugs, and weapons. Recent advances in THz applications have stimulated renewed interest regarding the biological effects associated with this frequency range. Biological effects studies are a valuable type of basic science research because they serve to enhance our fundamental understanding of the mechanisms that govern THz interactions with biological systems. Such studies are also important because they often times lay the foundation for the development of future applications. In addition, from a practical standpoint, THz biological effects research is also necessary for accurate health hazard evaluation, the development of empirically-based safety standards, and for the safe use of THz systems. Given the importance and timeliness of THz bioeffects data, the purpose of this review is twofold. First, to provide readers with a common reference, which contains the necessary background concepts in biophysics and THz technology, that are required to both conduct and evaluate THz biological research. Second, to provide a critical review of the scientific literature.
Partial purification and properties of nuclease 1 from barley malt

Abstract A sugar-unspecific nuclease has been purified 260-fold from barley malt diastase. The enzyme, a glycoprotein of 37 000 MW, is highly active on single-stranded polynucleotides at pH 5–6. The nuclease is inhibited by several adenine nucleotides, and it binds weakly to NADP-agarose and ATP-agarose.
Quantum Walks in Brain Microtubules—A Biomolecular Basis for Quantum Cognition?

Cognitive decisions are best described by quantum mathematics. Do quantum information devices operate in the brain? What would they look like? Fuss and Navarro () describe quantum lattice registers in which quantum superpositioned pathways interact (compute/integrate) as 'quantum walks' akin to Feynman's path integral in a lattice (e.g. the 'Feynman quantum chessboard'). Simultaneous alternate pathways eventually reduce (collapse), selecting one particular pathway in a cognitive decision, or choice. This paper describes how quantum walks in a Feynman chessboard are conceptually identical to 'topological qubits' in brain neuronal microtubules, as described in the Penrose-Hameroff 'Orch OR' theory of consciousness.
Preparation of macromolecular complexes for cryo-electron microscopy.

This protocol describes the preparation of frozen-hydrated single-particle specimens of macromolecular complexes. First, it describes how to create a grid surface coated with holey carbon by first inducing holes in a Formvar film to act as a template for the holey carbon that is stable under cryo-electron microscopy (cryo-EM) conditions and is sample-friendly. The protocol then describes the steps required to deposit the homogeneous sample on the grid and to plunge-freeze the grid into liquid ethane at the temperature of liquid nitrogen, so that it is suitable for cryo-EM visualization. It takes 4–5 h to make several hundred holey carbon grids and about 1 h to make the frozen-hydrated grids. The time required for sample purification varies from hours to days, depending on the sample and the specific procedure required. A companion protocol details how to collect cryo-EM data using an FEI Tecnai transmission electron microscope that can subsequently be processed to obtain a three-dimensional reconstruction of the macromolecular complex.
Athletic Participation in Severe Hemophilia: Bleeding and Joint Outcomes in Children on Prophylaxis

We sought to determine joint outcomes relative to im- pact level of athletic participation among school-aged children who had hemophilia and were taking prophylactic factor replacement, as well as to investigate prognostic factors for joint outcomes. METHODS: School-aged boys with severe hemophilia A or B at a single center were included in the study. Clinical data on baseline joint status, BMI, hemophilia treatment, bleeding episodes, joint assessments, ath- letic participation, and injuries were retrospectively reviewed. Data on athletic participation were supplemented, when incomplete in the medical record, via structured telephone interview. RESULTS: Among 37 children with severe hemophilia A or B receiving factor prophylaxis, 73% participated in high-impact activities, whereas 27% participated in exclusively low-impact activities. The frequency of joint hemorrhages and new injuries did not appreciably differ between high- and low-impact athletics. In most instances, children developed 1 bleed or injury per season. A new target joint developed in 1 (3%) child. Sixteen percent of children met established BMI criteria for over- weight, and 3% were obese. In logistic regression analyses with adjust- ment for prophylaxis frequency, level of athletic participation was not a significant prognostic factor for joint hemorrhage. CONCLUSIONS: In the setting of regular prophylaxis and adult coach- ing and supervision, significant bleeding complications were uncom- mon and level of impact of athletic participation was not a prognostic factor for joint outcomes. Athletic participation with appropriate su- pervision and precautions should be encouraged in children with he- mophilia receiving prophylaxis, given potential health benefits in an increasingly overweight pediatric population. Pediatrics 2009;124: 1266-1271
Data analysis and sample size issues in evaluations of community-based health promotion and disease prevention programs: A mixed-model analysis of variance approach

The growing interest in community-based approaches to health promotion and disease prevention (HP/DP) has been accompanied by a growing need to evaluate the effectiveness of such programs. Special issues that arise in these evaluation studies include (1) entire communities are assigned to intervention and control groups, (2) only a small number of communities can usually be studied, (3) the time course of changes in behavior and other outcomes is often of interest, and (4) surveys to measure such changes over time can be conducted with either repeated cross-sectional samples or with longitudinal samples. This paper shows how these issues can be addressed under a mixed-model analysis of variance approach. This approach serves to unify several ideas in the literature on evaluation of community studies, including use of time-series regression and the question of whether the individual or the community should be the unit of analysis. We also describe how the method can be used to estimate sample size requirements, statistical power, or minimum detectable program effect.
Method for least-squares analysis of gamma-ray scintillation spectra using a bent-crystal monochromator

Abstract A method is presented for determining gamma-ray relative intensities using features of the conventional least-squares analysis of a NaI pulse-height spectrum combined with the crystal-diffraction method. In studying the gamma rays from a radioactive source, a bent-crystal spectrometer is used as a gamma-ray monochromator to obtain monoenergetic gamma rays using a strong line source. The individual response functions of a NaI detector to these monoenergetic gamma rays are recorded in a multichannel analyzer. The NaI detector is then directly exposed to a second thin line source of the same source material, placed on the focal circle of the monochromator, and the composite pulse-height spectrum in the NaI detector of all gamma rays from the source is recorded. The relative intensities of the gamma rays are then determined by a least-squares adjustment of the appropriate linear combination of monochromatic response functions to obtain the best fit to the composite pulse-height spectrum. The relative intensities of gamma rays from 169 Tm following electron capture of 169 Yb obtained with this method show good agreement with those obtained using the crystal-diffraction method.
A Critical Analysis of Gender Mainstreaming

By definition, gender mainstreaming is the process by which a gendered perspective (male and female) is integrated into the fabric of our communities, institutions, and lives (United Nations 1997). We live in a society defined by our values of equality, social justice, and opportunity. In order for these values to permeate into our everyday lives, we must address issues of “separateness” that still seem to prevail in our institutions, particularly in our political science curricula. Di Stefano (1997, 204) presented gender as “a socially constructed and politically enforced notion of what it means to be male or female” and argues that this gendered lens is “political because it has the power to impose meaning and value to our activities and social relationships.” Mainstreaming is a transition from a male-defined curriculum to a more gender-balanced curriculum that better reflects the improved status of women in society.
The Pacification of Xinjiang: Uighur Protest and the Chinese State, 1988-2002

Efforts to repress dissent in Xinjiang are leading Uighurs to discover common grievances and interests.