cssi/SciSciGPT-SciSciNet huggingface dataset:
Mg2+ and the permeability of heart mitochondria to monovalent cations.

Abstract EDTA activates respiration-dependent ion accumulation and osmotic swelling in beef heart mitochondria and alters the monovalent cation selectivity of the reaction from K+ = Li+ > Na+ to Li+ > Na+ > K+. The chelator does not penetrate the matrix of the mitochondrion at neutral pH and the small amount of Mg2+ which it removes appears to be located outside of and on the outer surface of the inner membrane. Mitochondrial Mg2+ can be reduced from 30 to 2–4 nmol/mg protein by EDTA under conditions which permit the chelator to enter the matrix (pH 8 and swelling of the matrix). Mitochondrial Mg2+ also can be reduced to these low values in the absence of EDTA by addition of the divalent ionophore A23187. Respiration-dependent cation uptake is activated by EDTA in the A23187-treated mitochondria. EDTA is not bound to the membrane and does not penetrate the matrix under these conditions and it appears that removal of 1 nmol of Mg2+/mg (or less) by the chelator is responsible for an increase in transmembrane, electrophoretic permeability to monovalent cations and the change in the selectivity pattern. EDTA treatment and the level of endogenous mitochondrial Mg2+ have little effect on the Na + H + exchange reaction of the membrane. The studies suggest that specific pathways for electrophoretic penetration of monovalent cations are present in the inner membrane of the mitochondrion and that Mg2+ bound by a limited number of high-affinity sites in or near these pathways can control monovalent cation permeability.
Genotypic Detection of Antibiotic Resistance in "Escherichia Coli.": A Classroom Exercise.

Bacterial antibiotic resistance remains a problem of clinical importance. Current microbiological methods fordetermining antibiotic resistance are based on culturing bacteria, and may require up to 48 hours to complete. Molecular methods are increasingly being developed to speed the identification of antibiotic resistance and to determine its mechanism. This paper describes a fast and robust method of determining whether and how a particular strain of E.coliis resistant to the antibiotic ampicillin, using the Polymerase Chain Reaction. This exercise is designed to help students learn about modern methods for determining antibiotic resistance.
Pressure drop and liquid holdup in high pressure trickle-bed reactors

The vast majority of commercial trickle-bed reactors, fixed bed of catalyst particles contacted by cocurrent downflow of gas and liquid, operate at high pressure. In this study Holubet al.'s (1992, 1993) phenomenological model has been extended to describe the effect of high pressure (i.e. increased gas density) on pressure drop and liquid holdup in the trickle flow regime. This model, based on annular two-phase flow in a slit, ties pressure drop and liquid holdup but was previously verified only at atmospheric pressure. The advantage of this model is that the Ergun constantsE1 andE2, required by the model, are determined from single phase (gas) flow through the packing of interest and no two-phase flow data is needed. Experiments were conducted at high pressure over a range of gas and liquid velocities and different bed characteristics. The developed phenomenological analysis, describing the effect of high pressure and gas flow rate in terms of five limiting cases, matches well the experimental observations. The high pressure data collected in this study was used as a basis for comparing the prediction for pressure drop and liquid holdup of the model and of the available high pressure correlations. Holubet al.'s (1992) model matches experimental observations better than available correlations. It also predicts all trends in pressure drop and holdup correctly for all changes in operating variables such as pressure, liquid and gas superficial mass velocity and with physical properties of the gas and liquid.
The effects of negotiation and arbitration cost salience on bargainer behavior: The role of the arbitrator and constituency on negotiator judgment

Abstract Recent literature reports a reliance on third-party intervention procedures in contract negotiation. This study suggests that the relative evaluation of the costs related to arbitration (such as the uncertainty and expense of arbitration), and the costs related to negotiation (such as loss of face or perceived incompetency) provide a partial explanation for the increasing frequency of the negotiator's use of arbitration procedures rather than reaching a negotiated settlement. The relative salience of negotiation-related costs (high and low) and the relative salience of arbitration-related costs (high and low) were manipulated in a 2 × 2 design, involving 147 subjects negotiating a five-issue contract. The results were consistent with the hypothesized relationships. Implications of the results of this study for improving the understanding of and control over negotiator behavior are discussed.
Effect of substrate surface roughening and cold spray coating on the fatigue life of AA2024 specimens

Abstract The effects of cold spray coating and substrate surface preparation on crack initiation under cyclic loading have been studied on Al2024 alloy specimens. Commercially pure (CP) aluminum feedstock powder has been deposited on Al2024-T351 samples using a cold-spray coating technique known as high velocity particle consolidation. Substrate specimens were prepared by surface grit blasting or shot peening prior to coating. The fatigue behavior of both coated and uncoated specimens was then tested under rotating bend conditions at two stress levels, 180 MPa and 210 MPa. Scanning electron microscopy was used to analyze failure surfaces and identify failure mechanisms. The results indicate that the fatigue strength was significantly improved on average, up to 50% at 180 MPa and up to 38% at 210 MPa, by the deposition of the cold-sprayed CP-Al coatings. Coated specimens first prepared by glass bead grit blasting experienced the largest average increase in fatigue life over bare specimens. The results display a strong dependency of the fatigue strength on the surface preparation and cold spray parameters.
Interaction between furosemide-induced renal vasodilation and the prostaglandin system.

Abstract The effect of intravenous furosemide, 5 mg/kg, on renal hemodynamics as it relates to the prostaglandin cascade was examined in dogs. In 11 dogs the vasculature to the kidney was isolated and a femoral to renal arterial and a renal to femoral venous shunt was performed. With the use of a protein-free salt solution to perfuse the kidney for 3 minutes, the renal cortex was enriched with tritiated arachidonic acid. After blood perfusion to the kidney was re-established, the renal effluent radioactivity was followed before and after furosemide administration. Furosemide produced two types of response. In six dogs there was renal vasodilation, diuresis, and a three and one-half fold increase in renal venous radioactivity. In five dogs that were in renal failure, furosemide administration caused no change in renal blood flow, no diuresis and no increase in renal venous effluent radioactivity. On thin-layer chromatography most of the released radioactivity by the kidney after furosemide administration traveled as arachidonic acid. In a separate seven dogs, we measured the total unesterified arachidonic acid concentration in the plasma before and after furosemide by the use of gas chromatographyflame ionization. Even though in these dogs furosemide caused a significant increase in renal blood flow and diuresis, renal venous plasma levels of arachidonic acid were unaltered. Our data suggest that furosemide causes a release of arachidonic acid from the kidney from a small pool of fast turnover lipid stores and that the stimulus for arachidonic acid release after furosemide depends on an intrarenal mechanism whereby the diuresis is coupled to the increase in renal blood flow.
Fabrication of ultra high aspect ratio silica nanocone arrays by multiple shrinking mask etching

We propose and experimentally demonstrate a novel method to fabricate subwavelength silica nanocone arrays with high aspect ratio (∼7) for multifunctional surfaces having anti-reflective, self-cleaning, and anti-fogging properties.
Characterization of microstructure and mechanical behavior of sputter deposited Ti-containing amorphous carbon coatings

Abstract We report on the characterization of microstructure and mechanical properties of sputter deposited Ti-containing amorphous carbon (Ti-aC) coatings as a function of Ti composition. Ti-aC coatings have been deposited by unbalanced magnetron sputter deposition, in an industrial-scale four-target coating deposition system. The composition and microstructure of the Ti-aC coatings have been characterized in detail by combining the techniques of Rutherford backscattering spectrometry (RBS) and hydrogen elastic recoil detection (ERD), transmission electron microscopy (TEM), X-ray absorption near edge structure (XANES) spectroscopy and extended X-ray absorption fine structure (EXAFS) spectroscopy. At Ti compositions 8 at.%, XANES and EXAFS data indicate that the average Ti atomic bonding environment in Ti-aC coatings resembles that in cubic B1-TiC, consistent with TEM observation of precipitation of TiC nanocrystallites in the a-C matrix. Beyond the Ti dissolution limit, the Ti-aC coatings are nanocomposites with nanocrystalline TiC clusters embedded in an a-C matrix. A large scale, quasi one-dimensional composition modulation in the Ti-aC coatings was observed due to the particular coating deposition geometry. Elastic stiffness and hardness of the Ti-aC coatings were measured by instrumented nanoindentation and found to vary systematically as a function of Ti composition. Unlubricated friction coefficient of Ti-aC coatings against WC–Co balls was found to increase as the Ti composition increases. As Ti composition increases, the overall mechanical behavior of the Ti-aC coatings becomes more TiC-like.
Lewis acid enhancement of the ionic conductivity of simple salts

The interaction of the strong Lewis acids, aluminum chloride or niobium pentaflouride, with several different lithium salts produces materials that exhibit substantial ionic conductivity. This result is attributed to significant charge delocalization in the Lewis acid complex with the anion and the formation of complex non-crystalline materials.
The Nature of Work-Hardening

Two kinds of work-hardening are discussed, interaction-hardening and source-hardening. Interaction-hardening arises because a large stress must be applied to move a dislocation through a material which already contains a large number of dislocations. This paper is mainly concerned with source-hardening which occurs because the sources of easy glide become inactive. Additional glide occurs by the use of sources which act at a higher stress level. Source-hardening is the most important kind of hardening at small strains since then the dislocation density is small.The experimental stress-strain curves obtained by Rosi and Mathewson on pure aluminum crystals can be calculated theoretically as follows: At very low temperatures one assumes that one has a distribution of "free lengths" of dislocations. The Frank-Read mechanism for the production of dislocations is used. It is also assumed in accordance with electron microscope data that generation ceases after about 500 dislocation loops have been produced. Source-hardening therefore occurs as the sources of greatest "free length" are gradually used. At finite temperatures the following modifications are introduced: The total stress is the sum of the applied stress and the stress resulting from thermal fluctuations. In addition, Brown's electron microscope data indicates that a given source produces much more glide at high temperature than at low temperature. The present theory does not predict an equation of state and does check Rosi and Mathewson's data on this topic.Suggestions are made to explain the reason for the increased glide per source with increased temperature and to understand the way in which a source becomes inactive as a result of vacancy production.Numerous experiments are suggested.The major accomplishment of the paper is that it is able to show that the lamella structure found in the electron microscope pictures can be related to the mechanical properties of the metal single crystals.
Lp estimates of solutions of some partial differential equations

Abstract The author is concerned with the long time asymptotic behaviors of the global weak solutions of some nonlinear evolution equations. First of all, he derives some uniform L1 and L∞ upper bounds for the solutions, under some mild conditions. Then, by applying the well-known Fourier splitting method and the L1 estimates, he asserts the L2 decay estimates of the solutions. The rates of decay are sharp in the sense that the integral of the initial data over R is nonzero.
A new finite formulation for computational fluid dynamics: VII. The Stokes problem with various well-posed boundary conditions: symmetric formulations that converge for all velocity/pressure spaces

Abstract Symmetric finite element formulations are proposed for the primitive-variables form of the Stokes equations and shown to be convergent for any combination of pressure and velocity interpolations. Various boundary conditions, such as pressure, are accommodated.
L'avenir des relations entre les États-Unis et la Russie

Les politiques migratoires europeennes harmonisees utilisent le developpement local dans les pays de depart comme une alternative a la migration et cherchent a motiver les retours encadres des migrants, dans une perspective utilitariste du travail importe. Les migrants sont par definition des acteurs du developpement local, par les transferts d’epargne et les investissements de retour. Ces retours sont mis en œuvre par une circulation transnationale routinisee, qui structure un champ de mobilite post-migratoire. Mais ces pratiques supposent, plutot que des reglementations restrictives entravant la mobilite et des incitations au retour, l’acces aise a des titres de sejour de longue duree dans le pays d’immigration. Les mobilites sont multiformes et essentielles pour la croissance des deux pays, mais ne peuvent se passer de la liberte de circulation.
RESPONSES TO NOREPINEPHRINE OF NORMAL AND ISCHEMIC CANINE PURKINJE FIBERS ARE CONSISTENT WITH ACTIVATION OF DIFFERENT ALPHA 1-RECEPTOR SUBTYPES

INTRODUCTION Previously we found that WB4101 (WB) 10(-7) M competitively blocks three alpha 1-adrenergic receptor-effector responses: the increase in normal automaticity occurring in Purkinje fibers (PF) at high membrane potentials; the increase in abnormal automaticity occurring in PF at depolarized membrane potentials; and the prolongation of PF action potential duration. These observations are consistent with two different hypotheses: (1) WB blocks a single alpha 1-receptor subtype, which subserves different effector pathways; and (2) WB blocks different receptor subtypes, each of which subserves an independent pathway. The aim of this study was to test both hypotheses. METHODS AND RESULTS We used standard microelectrode techniques to study the concentration-dependent actions of three alpha 1-adrenoreceptor blockers (WB [alpha 1A > or = alpha 1D], 5-methylurapidil [5-MU] [alpha 1A > > alpha 1D], and UK52,046 [nonselective]) or norepinephrine (NE) effects in normal PF and in PF depolarized with a simulated ischemic solution ([K+]o = 10 mM; pO2 < 20 mmHg; pH 6.8; maximum diastolic potential -60 +/- 1 mV). In normally polarized PF, concentration-dependent actions of all blockers on both the positive chronotropic response and the prolongation of action potential duration completely coincide. In contrast, the response to NE of abnormal automaticity in "ischemic" PF differs from normals: there is a high sensitivity to WB and 5-MU and no response to UK52,046. CONCLUSIONS (1) A single receptor subtype appears responsible for both the alpha 1-induced prolongation of repolarization and the positive chronotropic effect in normal PF. (2) Two different receptor subtypes may be responsible for the alpha 1-induced effects on automaticity in normal and ischemic fibers. It is likely that the latter one is alpha 1A, and that consideration of antiarrhythmic therapy with alpha 1-adrenergic blockers should focus on this subtype as a potential target.
Aggregation of nanoscale iron oxyhydroxides and corresponding effects on metal uptake, retention, and speciation: I. Ionic-strength and pH

Abstract The capacity of nanosized particles to adsorb and sequester dissolved metals can be significantly impacted by the mechanism and extent of aggregation the particles have undergone, which in turn can affect the long-term fate and transport of potentially toxic metals in natural aqueous systems. Suspensions of monodisperse nanoscale iron oxyhydroxides were synthesized and subjected to increased pH (pH 8.0, 10.0) or ionic strength (0.1, 1.0 M NaNO 3 ) conditions to induce various states of aggregation prior to conducting macroscopic adsorption/desorption experiments with dissolved Cu(II) or Zn(II). The metal adsorption and retention capacities of the nanoparticle aggregates were compared to one another and to non-aggregated control nanoparticles, while the mode(s) of metal sorption to the nanoparticle surfaces were characterized by extended X-ray absorption fine structure (EXAFS) spectroscopy analysis. With increasing aggregation by both pH and ionic strength, the proportion of introduced zinc adsorbed to the iron oxyhydroxide nanoparticles progressively decreased from 45% on the monodispersed control particles to as low as 16% on the aggregates, while the proportion of introduced zinc retained upon desorption (obtained by lowering the suspension pH) increased from 7% on the control particles to as much as 17% on the aggregated particles. Copper exhibited a subtler trend of only slightly declining uptake (from 43% to 36%) and retention (from 35% to 30%) with increasing aggregation state. EXAFS analysis was consistent with the macroscopic results, showing relatively little change in Cu speciation between samples analyzed before and after the desorption step but significant increases in Zn–Fe interatomic distances and coordination numbers after desorption. This suggests the presence of both strongly- and weakly-bound zinc ions; the latter are likely affiliated with less stable, more distorted surface sorption sites and are thus more readily desorbed, resulting in the retention of zinc that is bound to more stable, less-distorted sorption sites. For both metals, inner-sphere bidentate sorption appears to dominate the sorption process to the nanoparticle aggregates, with potential structural incorporation into the aggregates themselves.
Grain Growth in Nickel Ferrites

A discussion of continuous and discontinuous grain growth in nickel ferrites is presented. Experimental evidence indicates that the presence of polyphase material is favored by excess nickel oxide and that discontinuous grain growth can be accounted for by excess iron oxide. Quantitative measurements of isothermal grain-growth rates in stoichiometric nickel ferrite yielded an energy of activation of 90 kcal. per mole for the process.
The Logic of Inhibitory Connectivity in the Neocortex

Although inhibition plays a major role in the function of the mammalian neocortex, the circuit connectivity of GABAergic interneurons has remained poorly understood. The authors review recent studies of the connections made to and from interneurons, highlighting the overarching principle of a high density of unspecific connections in inhibitory connectivity. Whereas specificity remains in the subcellular targeting of excitatory neurons by interneurons, the general strategy appears to be for interneurons to provide a global “blanket of inhibition” to nearby neurons. In the review, the authors highlight the fact that the function of interneurons, which remains elusive, will be informed by understanding the structure of their connectivity as well as the dynamics of inhibitory synaptic connections. In a last section, the authors describe briefly the link between dense inhibitory networks and different interneuron functions described in the neocortex.
A Portable Telerehabilitation System for Remote Evaluations of Impaired Elbows in Neurological Disorders

A portable teleassessment system was designed for remote evaluation of elbow impairments in patients with neurological disorders. A master device and a slave device were used to drive a mannequin arm and the patient's arm, respectively. The elbow flexion angle and torque were measured at both the master and slave devices, and sent to each other for teleoperation. To evaluate spasticity/contracture of the patient's elbow remotely, the clinician asked the patient to relax the elbow, moved the mannequin arm at a selected velocity, and haptically felt the resistance from the patient's elbow. In other tasks, the patient moved his/her elbow voluntarily and the clinician observed the corresponding mannequin arm movement and determined the active range of motion (ROM). The clinician could also remotely resist the patient's movement and evaluate the muscle strength. To minimize the effect of network latency, two different teleoperation schemes were used depending on the speed of the tasks. For slow movement tasks, real-time teleoperations were performed using control architectures that considered causality of the tasks, with performance similar to that during an in-person examination. For tasks involving fast movements, a teach-and-replay teleoperation scheme was used which provided the examiner with transparent and stable haptic feeling. Overall, the teleassessment system allowed the clinician to remotely evaluate the impaired elbow of stroke survivors, including assessment of the passive ROM, active ROM, muscle strength, velocity-dependent spasticity, and catch angle.
Rhabdomyolysis After Correction of Hyponatremia in Psychogenic Polydipsia Possibly Complicated by Ziprasidone

OBJECTIVE:To report a case of rhabdomyolysis related to correction of hyponatremia secondary to psychogenic polydipsia, possibly complicated by the use of ziprasidone.CASE SUMMARY:A 50-year-old white man treated for 3 weeks with ziprasidone 40 mg twice daily for chronic paranoid schizophrenia was admitted to the intensive care unit after a witnessed generalized seizure. Marked hypotonic hyponatremia was present secondary to psychogenic polydipsia. After correction of hyponatremia with intravenous NaCl 0.9%, he developed a substantial elevation in the creatine kinase level without any evidence of muscle trauma, stiffness, or swelling or any signs of neuroleptic malignant syndrome. Renal failure or compartment syndrome did not complicate the clinical picture.DISCUSSION:It is well known that severe hyponatremia can cause neurologic complications such as stupor, seizures, and even coma. Hyponatremia from water intoxication (n = 28) and its correction with intravenous fluids (n = 2) may cause non-neurologic co...
Solar wind travel time

A useful rule of thumb in solar terrestrial studies is that the solar wind travels 4 Earth radii (RE) per minute. Long-term studies of solar wind velocity [e.g., Luhmann et al., 1993; 1994] show that the median velocity is about 420 km/s, corresponding to 3.96 RE min−1. The quartiles are about 370 km/s and 495 km/s, corresponding to 3.48 Re min−1 and 4.66 Re min-1 respectively. This number helps estimate the delays expected when observing a discontinuity at a solar wind monitor; one example is ISEE-3 when it was at the forward libration point (about 60 min). It is also helpful for estimating how much time passes before the dayside magnetosphere is compressed as denser solar wind flows by (about 2.5 min).
The Role of Rossby Wave Breaking in Shaping the Equilibrium Atmospheric Circulation Response to North Atlantic Boundary Forcing

Abstract The role of Rossby wave breaking (RWB) is explored in the transient response of an atmospheric general circulation model to boundary forcing by sea ice anomalies related to the North Atlantic Oscillation (NAO). When the NCAR Community Climate Model, version 3, was forced by an exaggerated sea ice extent anomaly corresponding to one arising from a positive NAO, a localized baroclinic response developed and evolved into a larger-scale equivalent barotropic pattern resembling the negative polarity of the NAO. The initial baroclinic response shifted the phase speeds of the dominant eddies away from a critical value equal to the background zonal flow speed, resulting in significant changes in the spatial distribution of RWB. The forcing of the background zonal flow by the changes in RWB accounts for 88% of the temporal pattern of the response and 80% of the spatial pattern of the zonally averaged response. Although results here focus on one experiment, this “RWB critical line mechanism” appears to be ...
Memory Optimized Re-gridding for Non-uniform Fast Fourier Transform on FPGAs

The Discrete Fourier Transform (DFT) can be viewed as the Fourier Transform of a periodic and regularly sampled signal. The Non-Uniform Discrete Fourier Transform (NuDFT) is a generalization of the DFT for data that may not be regularly sampled in spatial or temporal dimensions. This flexibility allows for benefits in situation where sensor placement cannot be guaranteed to be regular or where prior knowledge of the informational content could allow for better sampling patterns than a regular one. NuDFT is used in applications such as Synthetic Aperture Radar (SAR), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI). Direct calculation of NDFT is time consuming and, in general, Non-uniform Fast Fourier Transform (NuFFT) is used. The key of computing NuFFT is to interpolate the non-uniformly sampled data onto a uniform grid and then use the Fast Fourier Transform. The interpolation process, called re-gridding or data-translation, is known to be the most time consuming (over 90% of the overall computation time of NuFFT) [1]. FPGA have been shown in prior work to be a power efficient way to perform this re-gridding as in [1]. We propose a novel memory-efficient FPGA based technique based on grouping the source points together in on-chip memory and hence reducing the number of memory accesses. The proposed architecture exhibits high performance for the re-gridding process. A speed-up of over 7.5 X was achieved when compared with existing FPGA-based technique for a target grid of size 256 atimes; 256. The basic procedure for re-gridding is based on updating all the target points within a specified distance of the source point using an interpolation kernel function. In this paper, we refer to this specified distance as interpolation threshold and its value is expressed in terms of the number of target points. Our proposed architecture is based on dividing the 2- Dimensional (2D) uniform target grid T into smaller 2D sub-grid. These sub-grids are called tiles. Corresponding to each tile, a block memory based FIFO is used. The idea is to group the source points that affect a tile into the FIFO corresponding to the tile. FIFOs are read one at a time and the tile corresponding to the FIFO being read is fetched from the external memory into the device. Performance of the proposed architecture is evaluated by simulating and computing the number of clock cycles required. Using a clock frequency of 50 MHz, which is chosen to be less then the achieved maximum frequency of 60.16 MHz, computation time for the translation process is calculated. Based on this computed time, throughput is calculated in terms of frames per second (fps).
The complex relationship between depressive symptoms and functional limitations in community-dwelling older adults: the impact of subthreshold depression

BackgroundDepressive symptoms above screening thresholds have been shown to predict functional decline in older adults. Less is known about the impact of subthreshold depression, and whether more symptoms confer significantly greater risk compared to fewer symptoms.MethodUsing data from the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE) collected over 10 years, we used repeated-measures mixed models to predict functional change by depression status at the prior (index) in-person interview. Depressive symptoms were measured using a modified version of the Center for Epidemiologic Studies Depression Scale (CES-D). Subthreshold depression was operationalized as 6–8 symptoms and CES-D-defined depression as 9–20 symptoms in the previous week. Three domains of functional status were assessed at the subsequent in-person interview: limitations in basic activities of daily living (ADL), instrumental ADL (IADL) and mobility.ResultsControlling for race, sex, age, education, marital status, cognitive status, health status, self-perceived health, perceived social support and functional status at the index interview, having ⩾6 depressive symptoms predicted an increase of 0.12 IADL limitations 3–4 years later (p=0.03). The incremental effect of CES-D-defined depression (⩾9 symptoms compared to 6–8 symptoms) was not significant, suggesting that the effect of more symptomatic depression did not add to that of subthreshold depression. CES-D score modeled as a continuous variable predicted functional change for all domains, but the relationship was not linear, supporting a possible threshold effect.ConclusionsThe relationship between depressive symptoms and functional change is complex, not necessarily linear, and may vary by tasks assessed.
Haematological values of the multimammate mouse Praomys (Mastomys) Natalensis

The haematological estimates on 55 multimammate mice, Praomys (Mastomys) natalensis, are recorded. The data are presented as means, standard deviations and ranges or confidence limits.
Enhancing polymer performance through graphene sheets

Graphene sheets were synthesized through intercalation and subsequent ultrasonic processing of graphite natural flakes. The resultant graphene has been characterized by X-ray diffraction, atomic force microscope and transmission electron microscope, and it was confirmed to be exfoliated into monolayer state. The exfoliated graphene was incorporated into epoxy resins and their mechanical performance was investigated. The critical stress fracture intensity factor, K1c, was calculated based on the three-point bending test, indicating that the toughness was increased by 41% with addition of 0.54 vol % exfoliated graphene in comparison with the neat resin. The tensile tests also suggested that the elastic modulus and tensile strength were increased by 25 and 10%, respectively. The fracture surface of modified epoxy resins was also examined by scanning electron microscope, and it showed typical features of ductile materials. This study provides a cost-effective way to reinforce polymers for engineering applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Initial experience with teriparatide in the United States

Teriparatide has been commercially available in the United States (US) for over 3 years. This summary spans the early experience with this therapy. As of December 31, 2005, over 235 000 patients had filled a prescription for teriparatide world-wide. Data collected from July to December 2004, from 15,000 retail pharmacies in the US, indicated that the mean age of patients was 67.5 years, and more recent data collected from January through October 2005 indicated that 90% of patients were female. According to market research conducted with prescribing physicians from February through March of 2005, it is estimated that over 80% of patients receiving prescriptions for teriparatide had already experienced one or more prior fractures. Since teriparatide is administered subcutaneously, it is important that patients receive training on the use of the teriparatide injection device (i.e., the pen device). Educational programs are available for those who have been prescribed teriparatide therapy. Patients may also contact a customer care program regarding a variety of topics, including pen device use. Based on patient feedback, design changes have been implemented in the pen device to facilitate optimal use. Updates have also been made to the prescribing information to reflect the post-marketing surveillance experience. Adverse experiences reported to date have been consistent with the current product label and with cumulative teriparatide clinical trial experience. As of December 31, 2005 no reports of pathology-confirmed osteosarcoma have been received for individuals who have been treated with teriparatide, either with the commercially available drug or in clinical trials. We are unaware of any reports of osteosarcoma in association with other preparations of teriparatide, or other peptides of parathyroid hormone, either in the setting of clinical trials or from marketed drug experience.
Tunable multi-wavelength SOA based linear cavity fiber laser source for optical communications applications

We propose and demonstrate a simple compact, inexpensive, SOA-based, multi-wavelength tunable (C- to L-band) fiber laser. A C-band design SOA is used, yet multi-wavelength operation either at the C or L-band region is accomplished by exploiting the gain compression phenomena of the SOA. We demonstrate that the wavelength tunability can be achieved either by inserting a variable attenuator inside the cavity of the laser or by changing the reflectivity of the mirrors. We exploit two different kinds of loop mirrors, a Sagnac and a Lyot-Sagnac loop mirror, which perform multiple functions. Stable multi-wavelength operation is achieved at room temperature without temperature compensation techniques, with measured power and the wavelength stability within &#60; ±0.5 dB and ±0.1 nm, respectively.
Self Beyond Ego: a New Perspective

The existential-transpersonal debate on development of self beyond ego has reached an apparent impasse. An approach that focuses more on attitude toward self than nature of self may allow the conversation to continue.
USE OF PRERIGOR BEEF FOR FROZEN GROUND BEEF PATTIES

- Differences in palatability, cooking characteristics, and storage effects were determined between conventionally processed ground beef patties and patties formulated immediately after slaughter (pre-rigor). Carcasses were split, the left sides processed immediately and the right sides processed after 48 hr aging. Freezer tunnel shrink, storage shrink, cooking loss, proximate analysis, pH, color, rancidity, and taste panel evaluations were made at 30-day intervals. Major differences include an elevated pH and decreased cooking loss for prerigor patties. Taste panels of > 100 consumers gave higher scores for prerigor patties on evaluations of tenderness, juiciness, and overall acceptability.
PHOTOELASTIC INVESTIGATION OF METAL-FORMING PROCESSES USING NEW SAPPHIRE DIES

Sapphire dies (of single-crystal aluminum oxide) are used to obtain interfacial conditions along the contact surface of the die in a strip-drawing operation. Several solutions based on slip-line field analysis and upper-bound techniques are available for metal-forming problems. However, these solutions generally neglect elasticity and work-hardening and assume that friction is constant along the die-work interface. While these analyses are sufficient for estimating forming loads, they cannot predict residual stresses nor do they accurately define the local stresses and deformations. Furthermore, inadequate information on the frictional conditions at the die-work interface precludes quantitative predictions of the actual forming process. In earlier research on the drawing of tin-plated mild steel with transparent dies, interfacial velocities were measured experimentally.'V2 The velocities were then used as the prescribed boundary conditions in the finite-element analysis to provide complete information on the stresses and strains throughout the deformation zone of the strip. There were some experimental difficulties in obtaining accurate velocity profiles along the die-work .interface, especially at the entry and exit regions, due to small contact length. The photoelastic technique was applied to the study of drawing operations about 30 years ago. Since the dies in those studies were made of photoelastic materials such as epoxy resins and fused quartz, only low-strength, nonstrain-hardening materials such as lead could be d r a ~ n . 3 , ~ Thus, the earlier work was not representative of commercial materials processing. By contrast, synthetic sapphire (aluminum oxide, Al203) is hard enough to machine and form commercial materials. The use of transparent sapphire dies in experimental studies of drawing makes the observation of tribological features at the die-work interface possible during processing commercial materials such as steel, aluminum, and copper?
Child-, adolescent- and young adult-onset depressions: differential risk factors in development?

Do child-, adolescent-, and adult-onset depression have the same risk correlates and precursors (Kaufman et al., 2001)? The answer to this question is unclear. Neurobiological and treatment research has found that usually two, but not all three, of these depression onset-groups share common correlates (Kaufman et al., 2001), suggesting a complex picture of both shared and non-shared pathways to the onset of depression at different points in development. If developmental subtypes of depression differed in terms of risk, examining them separately for purposes of biosocial research, prevention, and intervention would be important, as has been shown by research on developmental subtypes of antisocial behaviors (for a review, see Moffitt et al., 2006).
Advances in Understanding the Complex Mechanisms of DNA Interstrand Cross-Link Repair

DNA interstrand cross-links (ICLs) are lesions caused by a variety of endogenous metabolites, environmental exposures, and cancer chemotherapeutic agents that have two reactive groups. The common feature of these diverse lesions is that two nucleotides on opposite strands are covalently joined. ICLs prevent the separation of two DNA strands and therefore essential cellular processes including DNA replication and transcription. ICLs are mainly detected in S phase when a replication fork stalls at an ICL. Damage signaling and repair of ICLs are promoted by the Fanconi anemia pathway and numerous posttranslational modifications of DNA repair and chromatin structural proteins. ICLs are also detected and repaired in nonreplicating cells, although the mechanism is less clear. A unique feature of ICL repair is that both strands of DNA must be incised to completely remove the lesion. This is accomplished in sequential steps to prevent creating multiple double-strand breaks. Unhooking of an ICL from one strand is followed by translesion synthesis to fill the gap and create an intact duplex DNA, harboring a remnant of the ICL. Removal of the lesion from the second strand is likely accomplished by nucleotide excision repair. Inadequate repair of ICLs is particularly detrimental to rapidly dividing cells, explaining the bone marrow failure characteristic of Fanconi anemia and why cross-linking agents are efficacious in cancer therapy. Herein, recent advances in our understanding of ICLs and the biological responses they trigger are discussed.
Newmeyer's cyclic view of the history of generative grammar

In this book (henceforth, GL), Newmeyer has collected ii of his articles (including two co-authored ones), two of them previously unpublished, on the history of generative grammar, supplemented by reprints of two sections of Newmeyer 1986. Part I 'General trends' begins with two lightweight but interesting papers, 'Bloomfield, Jakobson, Chomsky, and the roots of generative grammar' (I I-I6) and 'The structure of the field of linguistics and its consequences for women' (I 7-22). Next comes 'Has there been a "Chomskyan revolution " in linguistics?' (23-38), in which Newmeyer takes a more sophisticated view of the notion 'scientific revolution' than have many authors, dividing the question into three parts: (i) Is the content of generative grammar, especially in the form in which it first achieved prominence, in Chomsky's Syntactic structures, 'revolutionary', in the sense of making a major break from the tradition within which it originated? (ii) Has the effect of Chomskyan generative generative grammar been such as to change substantially the kinds of questions that linguists ask and the kinds of answers to which they give serious consideration? (iii) Has generative grammar achieved institutional power within linguistics? In giving prominence to (ii) rather than to Kuhn's criterion of 'the resultant uniformity of belief, within the scientific community, in the new " paradigm "' (29),1 Newmeyer follows Larry Laudan in holding that scientific
Comparison of ventilatory expired gas parameters used to predict hospitalization in patients with heart failure.

Abstract Background Several ventilatory expired gas measures obtained during exercise testing demonstrate prognostic value in the heart failure (HF) population. Comparison of prognostic efficacy between pertinent measures is sparse. Methods The ability of various expressions of peak oxygen consumption (VO 2 ), the relationship between minute ventilation (VE) and carbon dioxide production (VCO 2 ), and the partial pressure of end-tidal carbon dioxide (P ET CO 2 ) were assessed to determine which measure(s) best predicted cardiac-related hospitalization over a 1-year period in subjects diagnosed with HF. Results Univariate Cox regression analysis found that several expressions of peak VO 2 , VE-VCO 2 relationship, and P ET CO 2 were significant predictors of hospitalization. Multivariate Cox regression analysis revealed that the VE/VCO 2 slope significantly predicted hospitalization (χ 2 = 29.1, P 2 and P ET CO 2 did not provide additional predictive value. Conclusions The prognostic superiority of the VE/VCO 2 slope over peak VO 2 may be a result of the latter measure's partial dependence on subject effort and skeletal muscle function. (Am Heart J 2002;143:427-32.)
CT Angiography-Source Image Hypoattenuation Predicts Clinical Outcome in Posterior Circulation Strokes Treated With Intra-Arterial Therapy

Background and Purpose— The aim of this study was to correlate CT angiography-source image (CTA-SI) parenchymal hypoattenuation with clinical outcome in patients with vertebrobasilar occlusion trea...
A versatile tool for student projects: an ASM programming language for the Lego mindstorm

Finding new and exciting senior design projects for undergraduate computer engineers can be challenging for both students and faculty advisors. The challenge is even more pronounced when attempting to construct interdisciplinary design projects to better meet ABET 2000 criteria and to better prepare graduating students for careers as engineers. We present an interdisciplinary, honors senior design project incorporating robotics control, algorithmic state machine design, reverse-engineering, assembly programming, and language, and basic compiler design. We believe this two-quarter project was extremely successful, and can be used as a model for similar design projects at other undergraduate institutions.
Sexual Risk Behavior 6 Months Post–High School: Associations with College Attendance, Living with a Parent, and Prior Risk Behavior

Abstract Purpose This study examined sexual risk behavior (SRB) among a community sample of youth in the fall after their senior year of high school. The primary goal was to examine associations between college and residential status and 3 measures of SRB: casual sex, inconsistent condom use, and high-risk sex. Method Data were from 834 participants in the Raising Healthy Children project who were surveyed annually during high school and in the fall of the post–high school year. Results Of the participants, 30% reported inconsistent condom use, 23% reported casual sex, and 11% reported high-risk sex in the fall after high school. Youth in college were less likely than noncollege youth to report SRB. The protective association between college attendance on one hand and casual sex and intermittent condom use on the other was fully explained by high school substance use, risky sex, and academic performance. The protective effect of college attendance on high-risk sex was partly explained by high school predictors. Living with parents at age 18–19 years was not related to SRB. Conclusions Results from this study indicate that the higher prevalence of SRB among noncollege youth is largely a continuation of patterns of higher risk behavior and lower academic performance during high school. College attendance was protective for the most high-risk sex measure. Findings suggest that human immunodeficiency virus and sexually transmitted infection prevention efforts are needed among young adults who are not attending college and among high school students who have earned poor grades, used drugs, or engaged in SRB.
Bone Socket Deficiency: Allografts and Augments

Acetabular bone deficiency in revision total hip arthroplasty is one of the most technically demanding and difficult procedures for an orthopedic surgeon. Acetabular reconstruction for Paprosky type IIB, type IIIA, and type IIIB used to require bulk allograft for reconstruction. We currently are using trabecular metal augments to obtain biological ingrowth and support for reconstructing these defects.
When Atoms Want.

Chemistry students and teachers often explain the chemical reactivity of atoms, molecules, and chemical substances in terms of purposes or needs (e.g., atoms want or need to gain, lose, or share electrons in order to become more stable). These teleological explanations seem to have pedagogical value as they help students understand and use abstract chemical models. They may, however, become a roadblock in developing mechanistic understandings of the structure and properties of chemical systems. I explore the explanatory preferences of college students with different levels of training in chemistry to determine the extent to which they prefer teleological explanations over causal explanations. Major results revealed a strong preference at all the targeted educational levels for explanations that invoke intentionality as a driver for chemical reactivity. I discuss the educational implications of these findings and invite chemistry educators to reflect on these issues.
The Women in Paul's Life:

Interest in the real lives of ancient women continues. This review essay considers three recent small books from Bruce Malina's new series “Paul's Social Networks: Brothers and Sisters in the Faith.”
Outcome After Relapse Among Children With Standard-Risk Acute Lymphoblastic Leukemia: Children's Oncology Group Study CCG-1952

Purpose The event-free survival (EFS) of children with standard-risk acute lymphoblastic leukemia (SR-ALL) is now more than 80%. However, prognosis after relapse continues to be poor. We examined postrelapse outcomes of children initially treated on the Children's Cancer Group CCG-1952 study. Patients and Methods We evaluated outcomes after bone marrow (BM) relapse and isolated extramedullary (EM) relapse for 347 patients with SR-ALL (WBC < 50,000/μL; age, 1 to 9 years). The prognostic significance of several factors for EFS after relapse (EFS2) was assessed by Cox regression analysis. Stem-cell transplant (SCT) was compared with chemotherapy as salvage treatment. Results The mean ± SE times to isolated central nervous system relapse, BM relapse, and isolated testicular relapse were 23 ± 1 months (range, 1 to 88 months), 36 ± 1 months (range, 2 to 79 months), and 40 ± 2 months (range, 16 to 64 months), respectively. The estimated percent ± SE 3-year EFS2 and overall survival rates after BM relapse were 37...