cssi/SciSciGPT-SciSciNet huggingface dataset:
Models for phase transitions with continuous constant energy surfaces

We have studied models of phase transitions of a type introduced by Brasovskii. These models involve an infinite number of degenerate order parameters, each associated with a finite nonzero wave vector. Brasovskii discussed the case of a spherical constant-energy surface in reciprocal space. We extend the Brasovskii model to different spatial dimensions $d$ and to different continuous constant-energy surfaces of dimension $m$. The ring model, the model discussed in most detail, has a continuous constant-energy surface described by a two-dimensional circle embedded in a $d$ dimensional space. The order of the phase transition to the nonuniform state is shown to depend on the number of independent directions orthogonal to the constant-energy surface in reciprocal space. When there are more than four directions perpendicular to the constant-energy surface ($dg5$ for the ring model), fluctuations are unimportant and the transition is continuous with mean-field exponents. However, when there are less than four directions ($dl5$ for the ring model), the phase transition to a nonuniform state is shown to be first order, rather than second order, as predicted by mean-field theory. We also present the analogous results for the more general models.
Endovascular Abdominal Aortic Aneurysm Repair

Although endovascular surgery for aortic aneurysms can be traced to the 19th century, open surgery has dominated during the past 50 years. Indeed, open repair of aneurysms has been one of the most successful developments in vascular surgery. Despite improvements in mortality rates, open repair remains a major operation often undertaken in patients with significant comorbidities. Starting from basic research dating back several decades, the 1990s were noted for very active clinical development of endovascular abdominal aortic repair in an attempt to provide an alternative to open repair, especially for high-risk patients. Early successes with decreased intensive care unit and hospital stays were tempered by technical issues and the “endoleak,” the term given to an incomplete exclusion of the aneurysm from the circulation. This potential for rupture, despite treatment, was cause for concern. The need for long-term surveillance and secondary procedures, if not conversion to open repair, further compounded th...
Successful endoscopic management of gastrojejunal anastomotic strictures after Roux-en-Y gastric bypass

Background Roux-en-Y gastric bypass is the most frequently performed bariatric surgery for morbid obesity. Gastrojejunal anastomotic strictures are a relatively frequent postoperative complication. Objective To evaluate the clinical outcomes and therapeutic response to through-the-scope balloon dilation performed to treat anastomotic strictures after Roux-en-Y gastric bypass surgery. Design Single-center, retrospective study. Setting Academic medical center. Patients Between 1997 and 2005, 801 patients with morbid obesity underwent Roux-en-Y gastric bypass surgery at our institution. Main Outcome Measurements The development of an anastomotic stricture after Roux-en-Y gastric bypass surgery. The response to through-the-scope balloon dilation after diagnosis. Results Forty-three of 801 patients (5.4%) developed an anastomotic stricture (26 of 294 open surgeries [8.8%]; 17 of 507 laparoscopic surgeries [3.4%]; P Limitations Single-center, retrospective study. Conclusions Endoscopic balloon dilation is a safe and effective method for the management of gastrojejunostomy strictures after Roux-en-Y gastric bypass. Dilation to at least 15 mm is safe and decreases the need for further endoscopic dilation.
Statistical relationships between the distributions of groundfish and crabs in the eastern Bering Sea and processed returns from a single-beam echosounder

McConnaughey, R. A., and Syrjala, S. E. 2009. Statistical relationships between the distributions of groundfish and crabs in the eastern Bering Sea and processed returns from a single-beam echosounder. - ICES Journal of Marine Science, 66: 1425-1432.Groundfish and benthic invertebrates are not randomly distributed over the continental shelf of the eastern Bering Sea (EBS). Annual trawl surveys reveal distributional patterns that vary according to species, and substantial interannual variation in these patterns suggests some degree of environmental control. Quantitative habitat models are developed to explain the distribution and abundance of species in the EBS. Simple models based on readily available data (temperature and depth) are somewhat informative, but offer limited practical value. Earlier research in the EBS indicated that surficial sediments affect the distribution and abundance of groundfish. However, traditional sampling with grabs and cores is impractical over large areas, and an efficient sampling strategy is needed. Echosounders allow surveys of large areas, but it is unknown if they measure the relevant properties of sediments. Seabed echoes from a calibrated, single-beam echosounder were recorded over 17 000 km of trackline covering the EBS shelf. Generalized additive models were used to fit acoustic and other variables to abundance data for ten species. The final models explained 28-77% of the variability in abundances, including a marginal contribution of 2-13% by the acoustic predictors.
Machines for lattice gauge theory

Abstract The most promising approach to the solution of the theory of strong interactions is large scale numerical simulation using the techniques of lattice gauge theory. At the present time, computing requirements for convincing calculations of the properties of hadrons exceed the capabilities of even the most powerful commercial supercomputers. This has led to the development of massively parallel computers dedicated to lattice gauge theory. This paper will discuss the computing requirements behind these machines, and general features of the components and architectures of the half dozen major projects now in existence.
Nucleation and Growth of Aerosol in Chemically Reacting Systems: A Theoretical Study of the Near-Collision-Controlled Regime

A theoretical treatment of the formation and growth of aerosols in systems where condensable molecules are generated at a constant rate is presented. Previous investigations of this type have focused either on collision-controlled (coagulation-limited) nucleation or on condensation /evaporation-controlled nucleation. In the latter case, classical nucleation theory has typically been used to determine particle formation rates, and coagulation of subcritical clusters is neglected. The present theory accounts for both coagulation and condensation / evaporation processes, and serves to bridge the gap between the two limiting cases. The aerosol population balance equations are cast in a nondimensional form and are solved numerically for the time-dependent size spectrum. A key aspect of this work is the identification of dimensionless parameters that have a significant influence on aerosol formation. The most important of these parameters is the evaporation parameter, E = , where N s is the saturation concentra...
Kinetic Tuning of Myosin via a Flexible Loop Adjacent to the Nucleotide Binding Pocket

A surface loop (25/50-kDa loop) near the nucleotide pocket of myosin has been proposed to be an important element in determining the rate of ADP release from myosin, and as a consequence, the rate of actin-myosin filament sliding (Spudich, J. A. (1991) Nature 372, 515–518). To test this hypothesis, loops derived from different myosin II isoforms that display a range of actin filament sliding velocities were inserted into a smooth muscle myosin backbone. Chimeric myosins were produced by baculovirus/Sf9 cell expression. Although the nature of this loop affected the rate of ADP release (up to 9-fold), in vitro motility (2.7-fold), and the V maxof actin-activated ATPase activity (up to 2-fold), the properties of each chimera did not correlate with the relative speed of the myosin from which the loop was derived. Rather, the rate of ADP release was a function of loop size/flexibility with the larger loops giving faster rates of ADP release. The rate of actin filament translocation was altered by the rate of ADP release, but was not solely determined by it. Through a combination of solute quenching and transient fluorescence measurements, it is concluded that, as the loop gets smaller, access to the nucleotide pocket is more restricted, ATP binding becomes less favored, and ADP binding becomes more favored. In addition, the rate of ATP hydrolysis is slowed.
Yield optimization in wafer scale circuits with hierarchical redundancies

Abstract For wafer scale integration, the concept of redundancy is important to yield enhancement and circuit repairability. In designing today's complex VLSI circuits, structured hierarchical design methodology in which a chip is partitioned into different levels of building blocks is generally preferred. The question naturally arises: Can hierarchy of redundancies be used to advantage? To maximize the circuit yield, we are therefore concerned with the size of the block at each level and the distribution of redundancies among blocks. This paper analyses the relationship between yield and the redundancy distribution for a two-level chip architecture with a given over-all redundancy overhead factor.
Reporting of Internal Control Weaknesses and Debt Rating Changes

This article examines the effect of corporate reporting of internal control weaknesses on debt rating changes. Bond rating agencies utilize (among other factors) financial statement information to assess a firm’s liquidity and long term solvency as important inputs in determining corporate debt rating. Reporting of internal control weaknesses increases the reliability and transparency risk of the financial statement information, which may lead rating agencies to revise corporate default risk. Our results indicate that reporting of internal control weaknesses is significantly associated with debt ratings after controlling for other firm specific factors. Specifically, these findings suggest that reporting of internal control weaknesses can result in downgrades of the firm’s outstanding debt.
A broader view of the job-shop scheduling problem

We define a job-shop scheduling problem with three dynamic decisions: assigning due-dates to exogenously arriving jobs, releasing jobs from a backlog to the shop floor, and sequencing jobs at each of two workstations in the shop. The job-shop is modeled as a multiclass queueing network and the objective is to minimize both the work-in-process WIP inventory on the shop floor and the due-date lead time due-date minus arrival date of jobs, subject to an upper bound constraint on the proportion of tardy jobs. A general two-step approach to this problem is proposed: 1 release and sequence jobs in order to minimize the WIP inventory subject to completing jobs at a specified rate, and 2 given the policies in 1, set due-dates that will attempt to minimize the due-date lead time, subject to the job tardiness constraint. A simulation study shows that this approach easily outperforms other combinations of traditional due-date setting, job release, and priority sequencing policies for two cases moderately loaded and heavily loaded of a particular shop. As a result of the study, three scheduling principles are proposed that can significantly improve the performance of a two-station job-shop; in particular, better due-date performance can be achieved by ignoring due-dates on the shop floor. Although we have only considered a two-station shop, the approach and scheduling principles presented here might also be useful for larger shops.
Inside the virtual casino: a prospective longitudinal study of actual Internet casino gambling.

Background: Participation in Internet gambling is growing rapidly, as is concern about its possible effects on the public's health. This article reports the results of the first prospective longitudinal study of actual Internet casino gambling behaviour. Methods: Data include 2 years of recorded Internet betting activity by a cohort of gamblers who subscribed to an Internet gambling service during February 2005. We examined computer records of each transaction and transformed them into measures of gambling involvement. The sample included 4222 gamblers who played casino games. Results: The median betting behaviour was to play casino games once every 2 weeks during a period of 9 months. Subscribers placed a median of 49 bets of €4 each playing day. Subscribers lost a median of 5.5% of total monies wagered. We determined a group of heavily involved bettors whose activity exceeded that of 95% of the sample; these players bet every fifth day during 17.5 months. On each playing day, these most involved bettors placed a median of 188 bets of €25. Their median percent of wagers lost, 2.5%, was smaller than that lost by the total sample. Conclusion: Our findings suggest that Internet casino betting behaviour results in modest costs for most players, while some, roughly 5%, have larger losses. The findings also show the need to consider time spent as a marker of disordered gambling. These findings provide the evidence to steer public health debates away from speculation and toward the creation of empirically-based strategies to protect the public health.
Ovarian development in mice requires the GATA4-FOG2 transcription complex.

We have demonstrated previously that mammalian sexual differentiation requires both the GATA4 and FOG2 transcriptional regulators to assemble the functioning testis. Here we have determined that the sexual development of female mice is profoundly affected by the loss of GATA4-FOG2 interaction. We have also identified the Dkk1 gene, which encodes a secreted inhibitor of canonical β-catenin signaling, as a target of GATA4-FOG2 repression in the developing ovary. The tissue-specific ablation of theβ -catenin gene in the gonads disrupts female development. In Gata4ki/ki; Dkk1-/- or Fog2-/-; Dkk1-/- embryos, the normal ovarian gene expression pattern is partially restored. Control of ovarian development by the GATA4-FOG2 complex presents a novel insight into the cross-talk between transcriptional regulation and extracellular signaling that occurs in ovarian development.
Isoniazid-induced elevation of CSF GABA levels and effects on chorea in huntington's disease

A randomized, double-blind, crossover, placebo-controlled clinical trial of oral isoniazid was undertaken in eight men with known Huntington's disease. Six completed the trial. Overall chorea scores indicated some amelioration, but clinical improvement was noticed in only two patients and was mild. Side effects included anorexia and elevation of liver enzyme levels. Cerebrospinal fluid (CSF) and plasma gamma-aminobutyric acid (GABA) concentrations were measured simultaneously. Mean CSF GABA increased threefold following treatment with isoniazid (414 +/- 52 SEM pmol/ml) compared to placebo (120 +/- 11 pmol/ml). No significant changes occurred in plasma GABA levels between the placebo and drug treatment phases. Reversal of central GABA deficiency appears not to correct extrapyramidal symptoms in Huntington's disease.
Supplemental data on line shifts and line profiles studies in an inductively coupled argon plasma

Abstract Line profiles of 10 Ar I lines emitted from an ICP ( T = 6800 K) are carefully evaluated with the Los Alamos Fourier Transform Spectrometer. In contrast to a previous paper, which reported measurements of 6p-4s, 5p-4s, and 4p-4s transitions (all 4s ground state), this Note deals with shifts for the transitions with 4p ground states. The shifts in line positions are on the order of 1 cm −1 . These shifts are accompanied by line profiles which have large contributions of pressure broadening. Previous work on a -parameters of elements in the analytical zone are on the order of 0.3–0.6 [1]. This note reports a-parameters as great as 39.03. Our HCL emission source could not be used as a standard because it lacked the excitation energy needed to adequately populate the higher energy levels. This results in a poor SNR for these lines. Argon I data reported by L i and H umphery [4] have been used for the unshifted values. It is the author's belief that with a large data set of experimentally determined line shifts from the ICP at a given set of operating conditions, a correlation between the magnitude of the line shift and the quantum numbers can be obtained for Ar.
Local structure analysis of Ca in Ba1-xCaxTiO3 ceramics

Ba1-xCaxTiO3 (x=0.05) (BCTO) ceramics has larger spontaneous polarization, and a little higher Curie temperature Tc than BaTiO3 (BTO). It is considered that these dielectric characteristics are caused by Ca doped to A-site in BTO. We have studied the atomic position of Ca in BCTO by First-Principles calculations and Extended X-ray Absorption Fine Structure (EXAFS) analyses. In the First-Principles calculations, geometry optimizations were done assuming that Ca is located at A-site in BTO under a constrain symmetry. The obtained result suggested that the Ca in BCTO (x=0.125) located at A-site is off about 0.30 A from the Ba equilibrium position along [001] direction. We have performed the Ca K-edge and Ba L3-edge EXAFS experiments, using synchrotron radiation, to obtain the information of local displacement of the Ca in BCTO (x=0.05). Analyses of radial structure functions showed that the Ca in BCTO (x=0.05) had a larger Debye-Waller factor than Ba in the same specimen. The interatomic distance of Ca-O (2.68 A) was shorter than that of the Ba-O (2.89 A) in BCTO (x=0.05). The offcenter position of Ca predicted by the First-Principles calculations was confirmed by EXAFS technique.
Pelvic anatomy on preoperative magnetic resonance imaging can predict early continence after robot-assisted radical prostatectomy.

Abstract Background and Purpose: Postoperative incontinence is multifactorial after radical prostatectomy. Using endorectal coil MRI, we examined features of the male urethra and accompanying muscular sphincter to predict continence after robot-assisted radical prostatectomy (RARP). Patients and Methods: 80 patients underwent preoperative 1.5 Tesla endorectal coil MRI. Urethral length was measured in the coronal plane. All patients underwent RARP. Questionnaires were completed by patients at monthly intervals. The primary end point was time to continence defined as necessitating 0 to 1 pad per day (PPD). Statistical analysis was performed using Cox regression models to create both univariate and multivariate survival models. Results: Mean age was 59.7 (standard deviation [SD] 7.1); 98% had bilateral nerve sparing. Mean urethral length was 17.1 mm (SD 4.5 mm). Mean prostate size was 34.7 g (SD 17.8). By 3 months, 60 patients achieved 1 PPD (mean 8.1 weeks, SD 9.4) and 34 patients achieved 0 PPD (mean 10.5 ...
Cross Talk Reduction by Photonic Crystal Cavities

Using a square lattice to reduce the cross talk between two photonic crystal structures composed of silicon pillars in air and air holes in silicon shows a reduction of -90.60 dB and -30 dB, respectively.
Asymmetric Okazaki piece synthesis during replication of simian virus 40 DNA in vivo

Abstract We have pulse-labeled simian virus 40 (SV40)-infected monkey cells with 3 H-thymidine ( 3 H-dThd) and have hybridized the viral Okazaki pieces (rapidly labeled short DNA chains found during DNA replication, We also measured the size of the Okazaki pieces using gel electrophoresis under denaturing conditons after releasing the pieces from the filter-bound DNA strands. The size distribution of the Okazaki piece DNA from each strand was the same (∼ 145 nucleotides, weight average; 200–250 nucleotides, maximum size), indicating that the hybridization asymmetry resulted from a difference in the number rather than the size of the pieces in each strand. The simplest interpretation of our results is that SV40 DNA is synthesized semidiscontinuously: the strand with 3′ → 5′ orientation away from the origin is synthesized in short Okazaki pieces which are subsequently joined together, while the strand with 5′ → 3′ orientation away from the origin is synthesized continuously. Some models of two-strand discontinuous synthesis, however, cannot be ruled out.
Health profiles in 5836 long-term cancer survivors.

Increasingly, prolonged survival follows the diagnosis of cancer. Cancer therapies result in complex and lasting health effects that create unique health-care needs for the survivors but are poorly understood (especially in survivors of adult cancers). Cancer survivors were asked to respond to a mailed health survey and provide medical and social information pertaining to their cancer experience. Information about demographics and perceived disease-related medical problems was analyzed. We analyzed the response of 5,836 survivors of adult cancers. Two-thirds of the responses came from women, and the response rate was 51% in both sexes. The mean interval since cancer diagnosis was 18.0 ± 8.5 years. Younger survivors and men were more likely to report that cancer had affected their health. The health effect most commonly reported by survivors was arthritis/osteoporosis (26% of respondents). Survivors of Hodgkin's disease prominently reported thyroid and lung problems (33.8% of responders with the diagnosis). Prior diagnosis of lymphoma was associated with frequent mention of memory loss (14.7%). The passage of time decreased some perceived effects (memory loss) but increased others (arthritis/osteoporosis, cataracts). Compared with the general population, the incidence of several age- and gender-adjusted health conditions in cancer survivors is different. This group of cancer survivors reported generally good health but outlined multiple lasting medical problems. The health survey described represents 1 approach to the development of comprehensive information about the health needs of cancer survivors. © 2003 Wiley-Liss, Inc.
Preference for insulin delivery systems among current insulin users and nonusers

Abstract Background: It is not known whether preferences for the vial and syringe (VS) or the insulin injection pen device (IIPD) differ between current insulin users and nonusers. Additional benefits in treatment might be realized if preference were considered when discussing insulin use with patients initiating or changing insulin treatment. Objective: The objective of this study was to examine respondent preferences for the VS and the IIPD between current insulin users and nonusers. Methods: US residents with type 1 or 2 diabetes mellitus who responded to a year-2001 mail survey completed a 19-item self-administered questionnaire designed to assess respondents' expectations of attributes related to the VS and IIPD. Items were analyzed on a 5-point Likert-type scale with higher scores indicating greater agreement that attributes met expectations. Composite scores for ease of use, activity interference, and social acceptability were used to further examine differences between insulin users and nonusers regarding their preferences for the VS or IIPD. Observed differences in preferences were evaluated statistically using the chisquare test, paired Student t test, and regression analysis. Results: Questionnaires were received from 302 respondents, producing an adjusted response rate of 20.8%. Respondents ranged in age from 18 to 83 years (mean [SD], 52.4 [13.2] years), with 62% reporting annual income above US $25,000. Of the 242 usable responses, 99 respondents were insulin users and 143 were not. Statistical evaluation using analysis of variance revealed significant regression coefficients ( P ≤ 0.001) for both insulin users and nonusers for each of the 3 dimensions (ease of use, activity interference, and social acceptability with respect to preference). Conclusions: Based on this survey analysis, overall preference for the IIPD appeared to be higher compared with the VS among both insulin users and nonusers. Social acceptability was the strongest predictor of preference for the IIPD. For current insulin users, social acceptability and ease of use were significant predictors of preference for the VS. For insulin nonusers, these results suggested that patient discussions about VS should emphasize activity interference and ease of use.
Before and after the inclusion of intervention events: an evaluation of alternative forecasting methods for tourist flows.

This article investigates the intervention impacts on tourist flows and evaluates the accuracy of various forecasting techniques to predict travel demand before and after the inclusion of intervention events. The forecasting methods used in this study include (1) Naive 1, (2) Naive 2, (3) Holt-Winter's model, (4) Seasonal Autoregressive Integrated Moving Average (SARIMA) model, and (5) Artificial Neural Networks (ANN). The Holt Winter's and Naive models are included for comparison purposes to ensure that minimum performance standards are being met. Data on air transport passengers including international arrivals and domestic air transport flows of the US (from January 1990 to June 2003) were obtained from the US Bureau of Transportation Statistics. This study focuses firstly on the importance for forecasting accuracy of allowing for intervention events in the modeling process. SARIMA models are therefore estimated both with and without intervention effects (the September 11th events). These models are used to generate forecasts for 2002 and the first part of 2003, and forecast accuracy is assessed using mean absolute percentage error and root mean square percentage error. The second focus of the study is to examine the impacts on tourism demand of the major crises that occurred during the period 2001–2003.
Subtleties of Self

“I’m so selfish!” sobs a patient who has been struggling to come to terms with rage about her father’s early sexual imposition and her parents’ lack of attunement to her distress. Each visitation of these issues is followed by devastating guilt and self-deprecation. The rage at her father turns into alarming attacks on her self. In so doing, my patient is using several unconscious defenses—chiefly identification with the aggressors, her parents, who frequently accused her of being selfish when she spoke of her feelings or needs. Also evident are reaction formation against and introjection of her rage. These are ego operations, served by cerebral functions, which help her contain her rage before someone gets hurt. But someone is in fact getting hurt—her self—and the outcome of such mental operations is sometimes selfmurder, otherwise known as suicide.
Nano-Gold Particles on Cerium Oxide for Catalytic Combustion of Formaldehyde

Nanometer-sized gold particles supported on Cerium Oxide (CeO2) were prepared by the method of deposition-precipitation. These catalysts exhibited good activity for the combustion of formaldehyde and the factors affected the activity of the catalyst were observed. The results showed that CeO2 powder prepared by Ce (NO3)3.6H2O and citric acid were small and gold can disperse on CeO2 easily. 1.83wt% Au/CeO2 exhibited the highest activity when velocity of 0.37% formaldehyde was 0.5L/min and corresponding contact time between gas and catalyst was 2h. Formaldehyde removal ratio after treating was up to 80% at 80°C and complete burn-off of formaldehyde was achieved at 120°C. The XRD and TEM results indicated that nanogold particles (≤20nm) were dispersed on cerium oxide homogeneously.
Improvement on thermoelectric properties of multilayered Si1−xGex/Si by ion beam bombardment

Abstract We made n-type nano-scale thin film thermoelectric (TE) devices that consist of multiple periodic layers of Si 1− x Ge x /Si. The period is about 10 nm. The structure was modified by 5 MeV Si ion bombardment that formed a nano-scale cluster structure. In addition to the effect of confinement of the phonon transmission, formation of nanoclusters by the ionization energy of incident MeV Si ions further increases the scattering of phonons, increasing the chance of inelastic interaction of phonons, resulting in more annihilation of phonons. This limits phonon mean free path. Phonons are absorbed and dissipated along the layers rather than in the direction perpendicular to the layer interfaces, therefore cross plane thermal conductivity is reduced. The increase of the density of electronic states due to the formation of nanocluster minibands increases the cross plane Seebeck coefficient and increases the cross plane electric conductivity of the film. Eventually, the thermoelectric figure of merit of the TE film increases.
The energetics of web-building in spiders

Abstract 1. 1. The cost of web-building and the standard metabolism of a sheet web-building wolf spider, Sosippus janus Brady, were measured at 25°C. 2. 2. The cost of activity is about 18% of the total cost of the web, the remainder being web silk cost. 3. 3. The cost of activity in sheet web-building was compared with a literature value for an orb-weaver and found to be similar. An average value is proposed as useful in estimating the cost of activity for other species of web-building spiders, given the weight of the web.
Chromosome 13q12 encoded Rho GTPase activating protein suppresses growth of breast carcinoma cells, and yeast two-hybrid screen shows its interaction with several proteins.

Abstract We have characterized the cDNA for a Rho GTPase activating protein (GAP) mapping to chromosome 13q12. The cDNA was characterized by determining the complete sequence of a 4.8 kb cDNA clone that represents the 5′ untranslated region (UTR), the translated region, and the 3′ UTR. The protein has a sterile α-motif (SAM), a distinct GAP domain, and a conserved START (StAR related lipid transfer) domain. The cDNA has 5 instability motifs (ATTTA) in the 3′ UTR and one motif in the translated region between GAP and START domains. The RhoGAP transcript is truncated in some breast carcinoma cell lines and it has low expression in other breast cancer cell lines as compared to a normal breast cell line. We have previously observed the absence of RhoGAP transcript in a breast tumor specimen. A GST-fusion of the RhoGAP was tested for its specificity on RhoA, Cdc42, and Rac1. The protein was most active for RhoA. Transfection of RhoGAP into MCF7 cells significantly inhibited cell growth. The introduction of the RhoGAP construct into MDAMB231 cells that had previously been transfected with a p21 construct did not affect cell proliferation, indicating the involvement of p21 in Rho-mediated proliferation of cancer cells. NIH3T3 cells overexpressing RhoGAP showed considerable inhibition of stress fiber formation. Several cDNAs were identified as RhoGAP interactors by using the yeast two-hybrid assay system. These cDNAs correspond to SWI/SNF, α-tubulin, HMG CoA reductase, and TAX1 binding protein (TAX1BP1). The interaction with HMG CoA reductase may partially explain the growth inhibition of breast carcinoma cells by statin class of cholesterol lowering drugs. The biological significance of the interacting proteins is discussed in the context of their involvement in tumorigenesis. Our results indicate that loss of RhoGAP or its altered activity suppresses the growth of breast tumor cells. The presence of various motifs in RhoGAP and its interaction with several other proteins suggest that the protein may regulate Rho signaling in multiple ways and possibly function in a Rho-independent manner.
A TCP model incorporating setup uncertainty and tumor cell density variation in microscopic extension to guide treatment planning

Purpose: Tumorcontrol probability (TCP) models have been proposed to evaluate and guide treatment planning. However, they are usually based on the dose volume histograms (DVHs) of the planning target volume (PTV) and may not properly reflect the substantial variation in tumor burden from the gross tumor volume (GTV) to the microscopic extension (ME) and to the margin of PTV. In this study, the authors propose a TCP model that can account for the effects of setup uncertainties and tumor cell density decay in the ME region. Methods: The proposed TCP model is based on the total surviving clonogenic tumor cells (CTCs) after irradiation of a known dose distribution to a region with a CTC distribution. The CTC density was considered to be homogeneous within the GTV, while decreasing exponentially in the ME region. The effect of random setup uncertainty was modeled by convolving the dose distribution with a Gaussian probability density function, represented by a standard deviation, σ . The effect of systematic setup uncertainty was modeled by summing each calculated TCP for all potential offsets in a Gaussian probability, represented by Σ . The model was then applied to simplified cases to demonstrate the concept. TCP dose responses were calculated for various GTV volumes, DVH shapes, CTC density decay coefficients, probabilities of lymph node metastasis, and random and systematic errors. The slopes of the dose falloff to cover the CTC density decay in the ME region and the margins to compensate setup errors were also analyzed in generalized cases. Results: The sigmoid TCP dose response curve shifted to the right substantially for a larger GTV, while modestly for cold spots in DVH. A dose distribution with a uniform dose within the GTV, and a linear dose falloff in the ME region, tended to cause a minimal TCP deterioration if a proper dose falloff slope was used. When the dose falloff slope was less steep than a critical slope represented by k T , the D 50 , which is the prescription dose at TCP = 50 % , and Γ 50 , which is the TCP slope at TCP = 50 % , varied little with different dose falloff slopes. However, both D 50 and Γ 50 deteriorated fast when the slopes were steeper than k T . The random setup error tended to shift the TCP curve to the right, while the systematic error tended to compress the curve downward. For combined random and systematic errors, we demonstrated that based on the model, a margin of ( 0.75 σ ) 2 + ( 1.15 Σ ) 2 added to the GTV was found to cause a TCP change corresponding to 2% drop at TCP = 90 % , or 0.5 Gy shift in D 50 . Conclusions: This study conceptually demonstrated that a TCP model incorporating the effects of tumor cell density variation and setup uncertainty may be used to guide radiation treatment planning.
Improved materials for blood-contacting applications: blends of sulphonated and non-sulphonated polyurethanes

Propyl sulphonate groups were grafted on to the urethane nitrogens of Pellethane 2363-80A at three levels: 1.2, 14, and 50%. Blends with an effective level of 1.2 and 14% were made by blending the 14 and 50% sulphonated polyurethanes with the unsubstituted material. Tensile testing was performed on the materials in both their dry and hydrated state. The blend materials exhibited a small improvement in tensile strength over their bulk analogues. Dynamic contact angle and X-ray photoelectron spectroscopy (XPS) showed an enrichment of sulphonate groups at the surface of the blend materials compared to bulk samples of the same overall composition. Canineex vivo shunt experiments revealed fewer platelets adherent and less platelet spreading on the blend materials than on the bulk materials with the same level of sulphonation. This suggests that sulphonated polyurethanes can be developed that have improved blood compatibility while maintaining good physical properties in an aqueous environment.
Clinical Indications Associated With Primary Cesarean Birth

Cesarean birth is the most common surgical procedure in the United States and is associated with increased morbidity and mortality when compared to vaginal birth. Of the more than 4 million births a year, one in three is now a cesarean. A better understanding of the clinical indications contributing to the current prevalence in primary cesarean rates can inform prevention strategies. This column takes a second look at two recent studies in which researchers evaluated the clinical indications associated with primary cesarean birth rates.
Investigation of Fluid Flow Out of a Microcavity Using μ PIV

This article presents the results of an experimental and corresponding analytical investigation of fluid flow out of a shallow microcavity (dimple) due to surface shear. An experimental test rig was designed, developed, and used to demonstrate shear-driven fluid flow out of a microcavity. The experimental test rig consists of a flat steel belt driven against a microcavity filled with a fluid. Microparticle image velocimetry (μ PIV) was employed to visualize the shear-driven cavity flow and generate the streamline contours of the flow field. Two different sets of experiments were conducted. The first set examines the important factors that affect the flow field, and these include the cavity depth-to-width ratio (aspect ratio) and the speed of the flat belt. The second set of experiments was designed to observe the important fluid flow phenomena including the extraction and stagnation of the fluid above and below a critical cavity depth. A model was also developed using the computational fluid dynamic softw...
Modeling of Star-shaped and Parallel-wire Carrier Distribution Systems

Abstract It is often desirable to represent carrier distribution systems by networks so that analysis can be made to predict the behavior of these systems. Modeling of two canonical carrier distribution systems, the star-shaped system and the parallel-wire system by networks was carried out in this paper. The representation is given in terms of lumped parameters when the lengths of the carrier lines are short and it is given in terms of lumped and distributed parameters when the lengths of the carrier lines are long.
Do physicians spend more time with non-English-speaking patients?

OBJECTIVE: To determine whether physicians at a general internal medicine clinic spend more time with non-Englishspeaking patients.
Education Policy Initiatives To Address The Nurse Shortage In The United States

Employment opportunities are expected to grow much faster for registered nurses (RNs) than for most other occupations. Yet a major shortage of nurses is projected by 2020. A nurse faculty shortage and financially strapped colleges and universities are limiting the ability of U.S. nursing schools to take advantage of historically high numbers of qualified applicants. Increased public subsidies are needed to provide greater access to nursing education, with a priority on baccalaureate and graduate nursing education, where job growth is expected to be the greatest.
Curriculum Specialist: Technician or Advocate?

(1979). Curriculum Specialist: Technician or Advocate? The Clearing House: A Journal of Educational Strategies, Issues and Ideas: Vol. 53, No. 4, pp. 175-176.
An investigation of the molecular basis for the synergistic interaction of tirapazamine and cisplatin.

Abstract Purpose: To determine if the observed tirapazamine (TPZ)–cisplatin synergistic cell kill was mediated at the cellular level by impairment of upregulation of key proteins involved in repair of DNA interstrand crosslinks. Cisplatin sensitivity has been shown to be dependent on the expression of the two DNA repair proteins ERCC1 and XPA. ERCC1 expression has also been shown to be upregulated by cisplatin exposure. Therefore, these studies were undertaken to determine if hypoxia-activated TPZ pretreatment inhibited the cells’ normal protective response to cisplatin via inhibiting the upregulation of ERCC1 and/or XPA expression. Methods and Materials: Two different cell lines, one cisplatin sensitive and one cisplatin resistant, were treated with TPZ, cisplatin, both drugs together (which results in additive cytotoxicity), or TPZ followed by cisplatin (which results in synergistic cytotoxicity). All cells were exposed to 1 h of hypoxia to bioactivate the TPZ. Expression of ERCC1 and XPA were evaluated at the mRNA and protein level at 24 or 48 h after drug exposure. Results: In the cisplatin-sensitive non–small-cell lung cancer cell line, ERCC1 expression at the mRNA or protein level was not significantly altered in any of the treatment groups. In the cisplatin-resistant ovarian cancer cell line, ERCC1 expression was upregulated by TPZ, but not by cisplatin alone. The change in protein expression was less pronounced than the change in mRNA level. XPA expression was not significantly changed from baseline in either cell line at the mRNA or protein level. Conclusion: In contrast to reports in the literature, this study did not demonstrate cisplatin inducing its own repair by upregulating the DNA crosslink repair proteins ERCC1 or XPA. Therefore, the TPZ–cisplatin synergism cannot be mediated through hypoxia-activated TPZ inhibiting this cellular protective response. TPZ alone, however, was able to alter repair protein expression, which may play a role in mediating its cytotoxicity.
Business Textbook Coverage of Aids in the Workplace: Results of a Survey

More than a decade after the first officially reported case in the United States, AIDS (Acquired Immune Deficiency Syndrome) now poses a major challenge for American organisations. Despite the plethora of coverage by the news media and an emerging literature in academic and practitioner journals, managers and business educators still lack clear and accurate information about the disease, the legal rights of its victims, and how organisations should deal with employees who have AIDS or who are infected with the HIV (AIDS causing) virus, but who remain asymptomatic.
Video pixel spectrometer for diagnostic imaging

There has been much evidence to suggest that diseased tissue is spectrally different from healthy tissue. Clinical endoscopy often results in fairly accurate diagnosis based on observed spectra (color), texture, and shapes of lesions. Conventional spectrometers lack the ability to coordinate adequate sampling of diseased verses healthy tissue to make a practical analytical tool. A video pixel spectrometer was developed which captures the spectra of a complete line of pixels within an image simultaneously. A color image of the suspicious tissue is continuously displayed which identifies a line through the image. This line represents the line of pixels which pass in to the spectrometer and is usually positioned to pass through the lesions. The spectrometer output spectrally disperses every pixel along the line simultaneously, resulting in the capture of the spectra of hundreds of pixels within the lesion and the surrounding tissue. The data can then be processed and correlated with shape and texture data for statistical classification of benign verses healthy tissue. This instrument was designed to couple to a variety of medical imaging instruments such as endoscopes, fundus cameras, macroscopic optics for dermatology, and microscopes.
Why does life speed up? The impact of cognitive aging

Abstract Why does life speed up as we age? Research on the impact of cognitive aging on personal memories is examined including declines in working memory, long-term memory, processing speed, processing resources and inhibition of unnecessary information. Attentional resources and distinctive processing decline. Life speeds up as we age because our strongest memories occur earlier in our lives. Events occurring in late adulthood simply do not undergo the same scrutiny of encoding, storage and retrieval as earlier life events. Research in this field informs both teachers and students as to the best ways to shape the adult learning experience.
Dynamic transmission electron microscopy of the [1,6-di(N-carbazolyl)-2,4-hexadiyue] diacetylene monomer-polymer phase transformation

Abstract The monomer-polymer transformation has been directly imaged in [1,6-di(N-carbazoly1-2-4-hexadiyne] diacetylene crystals by low-dose dynamic transmission electron microscopy. The crystallography of the phase transition has been studied by dynamic selected-area electron diffraction. The polymerizatibn was found to be quasihomogeneous, with the lattice parameters changing continuously through a series of crystalline intermediate states. The solid-state reaction was found to be analogous to a martensitic phase transition with three invariant planes: (001), (220), and (220). The transformation matrix Tmp relating the monomer and polymer crystal reciprocal lattices was determined. Diffraction streaks developed along directions normal to the (200) and (220) planes during the phase transformation. These streaks fade away at the end of the polymerization. The microstructural evolution during the polymerization reaction was also examined by dynamic dark-field and high-resolution electron microscopy.
Mechanisms and resistance in glucocorticoid control of inflammation

Glucocorticoids are the most effective anti-inflammatory therapy for many chronic inflammatory and immune diseases, such as asthma, but are relatively ineffective in other diseases such as chronic obstructive pulmonary disease (COPD). Glucocorticoids suppress inflammation by several mechanisms. Glucocorticoids suppress the multiple inflammatory genes that are activated in chronic inflammatory diseases, such as asthma, by reversing histone acetylation of activated inflammatory genes through binding of liganded glucocorticoid receptors (GR) to coactivator molecules and recruitment of histone deacetylase-2 (HDAC2) to the activated transcription complex. At higher concentrations of glucocorticoids GR homodimers interact with DNA recognition sites to activate transcription through increased histone acetylation of anti-inflammatory genes and transcription of several genes linked to glucocorticoid side effects. Decreased glucocorticoid responsiveness is found in patients with severe asthma and asthmatics who smoke, as well as in all patients with COPD and cystic fibrosis. Several molecular mechanisms of glucocorticoid resistance have now been identified. HDAC2 is markedly reduced in activity and expression as a result of oxidative/nitrative stress so that inflammation becomes resistant to the anti-inflammatory actions of glucocorticoids. Dissociated glucocorticoids have been developed to reduce side effects but so far it has been difficult to dissociate anti-inflammatory effects from adverse effects. In patients with glucocorticoid resistance alternative anti-inflammatory treatments are being investigated as well as drugs that may reverse the molecular mechanism of glucocorticoid resistance.
Initiation of lipid peroxidation by a peroxidase/hydrogen peroxide/halide system

A lactoperoxidase/H2O2/halide system caused the initiation of linoleate peroxidation as indicated by diene conjugation. Coupled lipid peroxidation was accelerated by iodide, chloride and bromide ions at pH 4.0 and 6.2. No peroxidation occurred in the presence of H2O2 or lactoperoxidase alone. The rate of linoleate peroxidation by lactoperoxidase in the presence of chloride depended on the concentration of H2O2. Linoleate peroxidation by the enzymatic system was inhibited by high concentration of H2O2 by methionine, tryptophan and BHT. Oxygen was absorbed during peroxidation and the major products were the 13-hydroperoxides. The mechanisms of the initiation of lipid peroxidation by a peroxidase/H2O2/halide system are discussed.
Oscillator strength of the CN violet system.

Abstract The electronic oscillator strength, f , for the CN violet system was determined by measuring the radiation from the shock layer about a hypervelocity projectile with a time-of-flight scanning spectrometer. The measured values at the Δ v = +1 and Δ v = -1 band sequences were f = 0·019±0·004 and f = 0·020±0·004, respectively, assuming a heat of dissociation Δ H 0 0 for CN of 8·2 eV. A parametric analysis of the radiation observed as a function of projectile velocity indicated that a Δ H 0 0 for CN of between 8·1 and 8·4 eV gave the best representation of the data.