bluuebunny/crossref_metadata_2025 huggingface dataset:
THE ASSOCIATION BETWEEN PHYSICIAN SUPPLY AND THE MIX OF GENERALIST AND SPECIALIST SERVICES USED
Authors: McLeod Logan
Published: October 2014

Variations in physician supply, and the impact on a patient's use of physicians, remains a concern. This article asks how the supply of physicians is associated with both the number of visits and the dollar value of services received from general practitioners and specialists. Ontario respondents in the Canadian Community Health Survey 2000/2001 are linked to their Ontario Health Insurance Program claims for 3 years (1999–2002). A geographic weighting method is employed to account for physician supply in surrounding jurisdictions. The results are consistent with the conclusion patients substitute one physician type for another when physician supply is constrained.(JELI10,I12,C29,C39,C52)
The imbalance of nature: revisiting a Darwinian framework for invasion biology
Authors: Fridley Jason D. , Sax Dov F.
Published: October 2014

Aim

A major implication of natural selection is that species from different parts of the world will vary in their efficiency in converting resources into offspring for a given type of environment. This insight, articulated by Darwin, is usually overlooked in more recent studies of invasion biology that are often based on the more modern Eltonian perspective of imbalanced ecosystems. We formulate a renewed Darwinian framework for invasion biology, the evolutionary imbalance hypothesis (EIH), based only on the action of natural selection in historically isolated populations operating within a global network of repeated environments. This framework predicts that successful invaders are more likely to come from biotic regions of high genetic potential (with independent lineages of large population size), experiencing a given environment for many generations and under strong competition from other lineages.

Location

Global.

Methods

We test the predictive power of this framework by examining disparities in recent species exchanges between global biotic regions, including patterns of plant invasions across temperate regions and exchanges of aquatic fauna as a result of modern canal building.

Results

Our framework successfully predicts global invasion patterns using phylogenetic diversity of the world's biotic regions as a proxy that reflects their genetic potential, historical stability and competitive intensity, in line with the Darwinian expectation. Floristic regions of higher phylogenetic diversity are more likely to be source areas of invasive plants, and regions of lower phylogenetic diversity are more likely to be invaded. Similar patterns are evident for formerly isolated marine or freshwater assemblages that have been connected via canals.

Main conclusions

We advocate an approach to understanding modern species invasions that recognizes the potential significance of both the original Darwinian explanation and the more modern view that emphasizes novel ecological or evolutionary mechanisms arising in the introduced range. Moreover, if biological invasions are a natural outcome of Darwinian evolution in an increasingly connected world, then invasive species should continue to displace native species and drive widespread shifts in the functioning of ecosystems.
Tax Competition, Investment Irreversibility and the Provision of Public Goods
Authors: Moretto Michele , Vergalli Sergio , Panteghini Paolo M.
Published: October 2014

This article studies the effects of tax competition on the provision of public goods under business risk and partial irreversibility of investment. As will be shown, the provision of public goods changes over time and also depends on the business cycle. In particular, under source-based taxation, in the short term, public goods can be optimally provided during a downturn. The converse is true during a recovery: in this case, they are underprovided. In the long term, however, tax competition does not affect capital accumulation. This means that the provision of public goods is unaffected by taxation.
Itemised Deductions: A Device to Reduce Tax Evasion
Authors: Piolatto Amedeo
Published: October 2014

With direct incentives and sanctions being the most common instruments to fight tax evasion, the theoretical literature has tended to overlook indirect schemes, such as itemised deductions, in which one agent’s behaviour affects the likelihood that others will declare their revenue. Itemised deductions provide an incentive for consumers to declare their purchases. This induces a partial shift in the demand from the black market to the legal one, for consumers need a transaction receipt to enjoy the tax deduction. I show that it is possible to increase tax proceeds by choosing a suitable level of itemised deduction, and this, for any level of taxation. Indeed, the cost for the tax authority on the consumers’ side is more than compensated for by the extra proceeds generated on the sellers’ side.
New quantitative aPTT waveform analysis and its application in laboratory management of haemophilia A patients
Authors: Milos M. , Coen Herak D. , Zupancic‐Salek S. , Zadro R.
Published: October 2014

Diagnosis of haemophilia A is usually made by the measurement of factor VIII (FVIII) activity that allows categorization of the disease severity. However, tests that assess global haemostasis may better reflect clinical features and give additional clinically relevant information. The aim of this study was to develop a new quantitative activated partial thromboplastin time (aPTT) waveform analysis and compare it with FVIII activities to find out whether waveform parameters are superior determinants of clinical phenotype. A total of 81 haemophilia A patients divided into two groups (37 severe, 44 non‐severe) were included in the study. The control group comprised 101 healthy male volunteers. Quantitative aPTT waveform analysis was performed with Actin FS on BCS (Siemens Healthcare Diagnostics, Marburg, Germany) using three parameters (DELTA, RATIO‐1, RATIO‐2) obtained from a single aPTT measurement with two evaluation modes. FVIII activities were measured by one‐stage clotting and two‐stage chromogenic assay. Statistically significant difference (P < 0.001) between control group and all haemophilia A patients, as well as between severe and non‐severe haemophilia A patients was obtained for all quantitative waveform parameters. Our study revealed parameter DELTA as the best waveform parameter, showing significant correlation with FVIII activities and clinical parameters, and excellent performance for distinguishing between severe and non‐severe haemophilia A patients (ROC analysis: sensitivity 97.3%, specificity 93.2%). The results obtained by new quantitative aPTT waveform analysis were superior to those obtained by standard laboratory methods. The simplicity and cost‐benefit of the method make this approach a reasonable and promising tool for assessing coagulation in haemophilia A patients.
Safety and efficacy of turoctocog alfa (NovoEight®) during surgery in patients with haemophilia A: results from the multinational guardian™ clinical trials
Authors: Santagostino E. , Lentz S. R. , Misgav M. , Brand B. , Chowdary P. , Savic A. , Kilinc Y. , Amit Y. , Amendola A. , Solimeno L. P. , Saugstrup T. , Matytsina I.
Published: October 2014

Recombinant factor VIII (rFVIII) products provide a safe and efficacious replacement therapy for prevention and treatment of bleeding episodes in patients with haemophilia A. The present investigations from the multinational, open‐label guardian™ clinical trials assessed the haemostatic response of turoctocog alfa (NovoEight®), a rFVIII product, in patients with severe haemophilia A (FVIII ≤ 1%) undergoing surgery. All patients had a minimum of 50 exposure days to any FVIII product prior to surgery and no history of inhibitors. A total of 41 procedures (13 orthopaedic, 19 dental and 9 general) were performed in 33 patients aged 4–59 years. Of the 41 procedures, 15 were major surgeries in 13 patients and 26 were minor surgeries in 21 patients. The success rate for haemostatic response was 100% (success was defined as ‘excellent’ or ‘good’ haemostatic outcome). Turoctocog alfa consumption on the day of surgery ranged from 27 to 153 IU kg−1. The mean daily dose declined over time, while retaining adequate FVIII coverage as measured by trough levels. Overall, no safety issues were identified. No thrombotic events were observed and none of the patients developed FVIII inhibitors. In conclusion, the present results show that turoctocog alfa was effective in controlling blood loss by obtaining a sufficient haemostatic response in patients with severe haemophilia A undergoing surgery.
Pharmacokinetics of plasma‐derived vs. recombinant FVIII concentrates: a comparative study
Authors: Morfini M. , Marchesini E. , Paladino E. , Santoro C. , Zanon E. , Iorio A.
Published: October 2014

Only very few pharmacokinetic (PK) studies comparing plasma derived FVIII (pd‐FVIII) against recombinant FVIII (rFVIII) concentrates are available. The studies have been generally conducted to demonstrate the bioequivalence of a new product with an old one. The switch from a plasma‐derived FVIII (pd‐FVIII) to a rFVIII concentrate is a good moment to enrol the patients in a comparative PK study. To achieve information on the PK characteristics of two different classes of FVIII concentrates, according to two different designs: a 10 FVIII concentration/time point design and a reduced 4‐point design. A single dose PK comparing pd‐ and rFVIII concentrates has been performed in four Haemophilia Centres of Italy. Seventeen haemophilia A patients underwent two subsequent single dose PK studies at the moment of switching. Two‐compartment‐ and Non‐compartment‐analysis did not show significant differences between the outcomes of PK of pd‐FVIII and rFVIII, due to inter‐patient variability. In vivo recovery (IVR) of rFVIII was slightly higher than that of pd‐FVIII and rFVIII/pd‐FVIII AUC ratio was 1.37 in 11/17 patients. The difference is only due to the initial distribution phase because after the first 10 h from the end of the infusion, the two decay curves are overlapping. The elimination half‐life of the concentrates was very similar even though a complete bioequivalence was not demonstrated because of a higher AUC of rFVIII concentrates, limited to the distribution phase. The higher Cmax and IVR of rFVIII may be due to the presence of heterodimers activated forms of the recombinant molecules.
IS COMPARATIVE HISTORY POSSIBLE?
Authors: LEVINE PHILIPPA
Published: October 2014

In recent years the trend toward comparative histories, frequently read in terms of transnational studies, has produced some remarkably exciting work. The prospect of the comparative is gaining broader appeal, a development we should applaud but at the same time begin to examine in a critical fashion. This essay lays out some of the problems involved in comparative work and suggests ways in which we might profitably utilize these potential snares in productive ways.

Comparative history has the potential to operate as a “bridge‐builder,” encouraging inventive thinking that moves scholars beyond the familiar terrain of their training. In this respect, it encourages original and innovative ways of approaching historical work. But there are lessons to be learned and problems to be faced in managing a complex scholarly enterprise of this kind. Comparative work runs the risk of reproducing and consolidating older models of universalist history that assume universal standards. It further runs the risk of assuming rather than historicizing the idea of the nation as a fixed point of historical reference rather than seeing the nation itself as a site for historical scrutiny. In this paper, my goal is to lay out these problems alongside the palpable rewards of comparative work, and then to suggest how we might turn such problems to our advantage.
WHAT IS A SCHOLARLY PERSONA? TEN THESES ON VIRTUES, SKILLS, AND DESIRES
Authors: PAUL HERMAN
Published: October 2014

What is the problem that “epistemic virtues” seek to solve? This article argues that virtues, epistemic and otherwise, are the key characteristics of “scholarly personae,” that is, of ideal‐typical models of what it takes to be a scholar. Different scholarly personae are characterized by different constellations of virtues and skills or, more precisely, by different constellations of commitments to goods (epistemic, moral, political, and so forth), the pursuit of which requires the exercise of certain virtues and skills. Expanding Hayden White's notion of “historiographical styles” so as to encompass not only historians' writings, but also their nontextual “doings,” the article argues that different styles of “being a historian”—a meticulous archival researcher, an inspired feminist scholar, or an outstanding undergraduate teacher—can be analyzed productively in terms of virtues and skills. Finally, the article claims that virtues and skills, in turn, are rooted in desires, which are shaped by the examples of others as well as by promises of reward. This makes the scholarly persona not merely a useful concept for distinguishing among different types of historians, but also a critical tool for analyzing why certain models of “being a historian” gain in popularity, whereas others become “old‐fashioned.”
PHILOSOPHY IN TRANSITION: JOHN DEWEY'S “LOST” MANUSCRIPT
Authors: GRIGORIEV SERGE
Published: October 2014

The intention of this essay is to offer a reading of John Dewey's recently found manuscript (considered lost for decades), Unmodern Philosophy and Modern Philosophy, as a kind of philosophical history leading up to the formulation of the key problems to be addressed by the general framework of Dewey's cultural naturalism. I argue, first, that cultural naturalism has direct implications for the way that we think about history, and that Dewey's recently recovered manuscript reflects this in its conception of the purpose and mode of historical reconstruction. Second, the essay presents a synoptic overview of the historically emergent thought‐conditions structuring, according to Dewey's narrative, the possibilities of the philosophical discourse of modernity. In conclusion, I argue that cultural naturalism allows us to move beyond these problems by a radical revision of the terms in which we construe the idea of “persons.” Specifically, instead of thinking about persons in terms of embodied minds, we should start thinking about them as participants in histories, carving their individual paths through the world of events, with their existence being essentially both temporal and social. I also suggest that this view of persons allows us to outline a promising account of the notion of human freedom, couched in terms of historical social agency.
Fluorescence in situ hybridization on human metaphase chromosomes detected by near‐field scanning optical microscopy
Authors: MOERS M. H. P. , KALLE W. H. J. , RUITER A. G. T. , WIEGANT J. C. A. G. , RAAP A. K. , GREVE J. , DE GROOTH B. G. , VAN HULST N. F.
Published: October 2014

Fluorescence in situ hybridization on human metaphase chromosomes is detected by near‐field scanning optical microscopy. This combination of cytochemical and scanning probe techniques enables the localization and identification of several fluorescently labelled genomic DNA fragments on a single chromosome with an unprecedented resolution. Three nucleic acid probes are used: pUC1. 77. p1–79 and the plasmid probe α‐spectrin. The hybridization signals are very well resolved in the near‐field fluorescence images, while the exact location of the probes can be correlated accurately with the chromosome topography as afforded by the shear force image.
Effects of Early Adolescent Alcohol Use on Mid‐Adolescent School Performance and Connection: A Longitudinal Study of Students in Victoria, Australia and Washington State, United States
Authors: Hemphill Sheryl A. , Heerde Jessica A. , Scholes‐Balog Kirsty E. , Herrenkohl Todd I. , Toumbourou John W. , Catalano Richard F.
Published: October 2014

BACKGROUND

This article examines the effect of early adolescent alcohol use on mid‐adolescent school suspension, truancy, commitment, and academic failure in Washington State, United States, and Victoria, Australia. Also of interest was whether associations remain after statistically controlling for other factors known to predict school outcomes.

METHODS

State‐representative student samples were surveyed in 2002 (grade 7; N = 1858) and followed up annually to 2004 (grade 9) in both sites. Students completed a modified version of the Communities That Care survey to report alcohol use, school outcomes, and risk and protective factors. Response rates were above 74% and retention rates exceeded 98% in both places.

RESULTS

Controlling for grade 7 risk factors, grade 7 current alcohol use, and heavy episodic drinking were associated with grade 8 school suspension. Grade 7 current and frequent alcohol use and heavy episodic drinking were linked to grade 9 truancy. In fully adjusted analyses, associations between early alcohol use and academic failure and low school commitment did not remain.

CONCLUSIONS

Although alcohol use is one factor influencing school performance and connection, there are other risk factors that need to be targeted to improve school outcomes.
Promoting Teacher Adoption of Physical Activity Breaks in the Classroom: Findings of the Central Texas CATCH Middle School Project
Authors: Delk Joanne , Springer Andrew E. , Kelder Steven H. , Grayless Megan
Published: October 2014

BACKGROUND

Research suggests that physical activity breaks (ABs) during class increase students' physical activity levels and provide an academic benefit. This study evaluates a 3‐year intervention aimed at encouraging teacher AB use.

METHODS

Thirty central Texas middle schools were assigned to 1 of 3 conditions: training‐only (Basic), training plus facilitator support (Basic Plus), and training/facilitator support and a social marketing campaign (Basic Plus SM). Teachers completed surveys at end of years 2 (N = 1039) and 3 (N = 831) to assess exposure to program, self‐efficacy, and frequency of AB use.

RESULTS

At end of year 3, teachers in facilitator‐supported conditions reported increased exposure, self‐efficacy, and use compared to Basic condition. Only 43.2% of teachers in the Basic condition reported receiving training in ABs compared to 84.2% and 90.6% in the Basic Plus and Basic Plus SM conditions, respectively. Additionally, a greater percentage of teachers in the facilitator‐support conditions reported conducting ABs weekly (Basic = 23.3%, Basic Plus = 34.4%, Basic Plus SM = 38.7%, at year 3; p < .001).

CONCLUSIONS

Despite perceived barriers, including fear that ABs will detract from instructional time, the intervention was successful in having a core group of teachers implement them weekly. More research is needed to increase the percentage of teachers implementing ABs regularly.
Physical Activity Breaks and Facilities in US Secondary Schools
Authors: Hood Nancy E. , Colabianchi Natalie , Terry‐McElrath Yvonne M. , O'Malley Patrick M. , Johnston Lloyd D.
Published: October 2014

BACKGROUND

Research on physical activity breaks and facilities (indoor and outdoor) in secondary schools is relatively limited.

METHODS

School administrators and students in nationally representative samples of 8th (middle school) and 10th/12th grade (high school) students were surveyed annually from 2008‐2009 to 2011‐2012. School administrators reported information about physical activity breaks and facilities. Students self‐reported height, weight, and physical activity.

RESULTS

The prevalence of physical activity breaks and indoor and outdoor facilities (dichotomized by median split) differed significantly by region of the country, school size, student race/ethnicity, and school socioeconomic status (SES). Breaks were associated with lower odds of overweight (adjusted odds ratio [AOR] = 0.91, 95% confidence interval [CI]: 0.83‐1.00) and obesity (AOR = 0.86, 95% CI: 0.75‐0.99) among middle school students. Among low‐SES middle school students and schools, higher indoor facilities were associated with lower rates of overweight and obesity. Among high school students, higher indoor and outdoor facilities were associated with 19‐42% higher odds of moderate‐to‐vigorous physical activity.

CONCLUSIONS

Physical activity breaks and school facilities may help to address high rates of overweight/obesity and low physical activity levels among secondary students, especially lower‐SES students. Students in all schools should have equal access to these resources.
Psychomotor vigilance performance predicted by Epworth Sleepiness Scale scores in an operational setting with the United States Navy
Authors: Shattuck Nita Lewis , Matsangas Panagiotis
Published: October 2014

It is critical in operational environments to identify individuals who are at higher risk of psychomotor performance impairments. This study assesses the utility of the Epworth Sleepiness Scale for predicting degraded psychomotor vigilance performance in an operational environment. Active duty crewmembers of a USA Navy destroyer (N = 69, age 21–54 years) completed the Epworth Sleepiness Scale at the beginning of the data collection period. Participants wore actigraphs and completed sleep diaries for 11 days. Psychomotor vigilance tests were administered throughout the data collection period using a 3‐min version of the psychomotor vigilance test on the actigraphs. Crewmembers with elevated scores on the Epworth Sleepiness Scale (i.e. Epworth Sleepiness Scale >10) had 60% slower reaction times on average, and experienced at least 60% more lapses and false starts compared with individuals with normal Epworth Sleepiness Scale scores (i.e. Epworth Sleepiness Scale ≤10). Epworth Sleepiness Scale scores were correlated with daily time in bed (P < 0.01), sleep (P < 0.05), mean reaction time (P < 0.001), response speed 1/reaction time (P < 0.05), slowest 10% of response speed (P < 0.001), lapses (P < 0.01), and the sum of lapses and false starts (P < 0.001). In this chronically sleep‐deprived population, elevated Epworth Sleepiness Scale scores identified that subset of the population who experienced degraded psychomotor vigilance performance. We theorize that Epworth Sleepiness Scale scores are an indication of personal sleep debt that varies depending on one's individual sleep requirement. In the absence of direct performance metrics, we also advocate that the Epworth Sleepiness Scale can be used to determine the prevalence of excessive sleepiness (and thereby assess the risk of performance decrements).
Label‐free visualization of acetaminophen‐induced liver injury by high‐speed stimulated Raman scattering spectral microscopy and multivariate image analysis
Authors: Satoh Shuya , Otsuka Yoichi , Ozeki Yasuyuki , Itoh Kazuyoshi , Hashiguchi Akinori , Yamazaki Ken , Hashimoto Hiroyuki , Sakamoto Michiie
Published: October 2014

We recently established a high‐speed, label‐free, spectral imaging method based on stimulated Raman scattering (SRS). This method enables examination of cellular features within relatively short periods, thus enabling new imaging applications in pathology. Previously, we reported on label‐free visualization of mouse tissue using SRS spectral microscopy combined with multivariate image analysis, but the feasibility of applying this approach to diseased tissues with diverse morphology and irregular chemical species has not been examined. We, therefore, assessed acetaminophen‐induced liver injury to evaluate the potential use of Raman spectral microscopy for visualizing histopathologic specimens. Acetaminophen‐overdosed mouse liver was prepared and the pathologic changes including centrilobular necrosis were confirmed. Multi‐colored images were reconstructed through principal component analysis (PCA) of a multi‐band SRS dataset, which provided rich information compared with a monochrome single‐band SRS dataset. A wide view of the multi‐colored principal component (PC) images showed the distribution of cellular constituents, which was similar to that observed by fat staining. In addition, different types of cells in liver parenchyma were also demonstrated. In conclusion, the combination of SRS spectral microscopy and PCA has the potential to reveal both the morphological and chemical features of specimens and therefore has potential utility in diagnostic pathology.
Oval Flow Mode Between Two Corotating Disks With Stationary Shroud
Authors: Hsu Ching Min , Chen Jia-Kun , Hsieh Min Kai , Huang Rong Fung
Published: October 2014

The characteristic flow behavior, time-averaged velocity distributions, phase-resolved ensemble-averaged velocity profiles, and turbulence properties of the flow in the interdisk midplane between shrouded two corotating disks at the interdisk spacing to disk radius aspect ratio 0.2 and rotation Reynolds number 3.01 × 105 were experimentally studied by flow visualization method and particle image velocimetry (PIV). An oval core flow structure rotating at a frequency 60% of the disks rotating frequency was observed. Based on the analysis of relative velocities, the flow in the region outside the oval core flow structure consisted of two large vortex rings, which move circumferentially with the rotation motion of the oval flow core. Four characteristic flow regions—solid-body-rotation-like region, buffer region, vortex region, and shroud-influenced region—were identified in the flow field. The solid-body-rotation-like region, which was featured by its linear distribution of circumferential velocity and negligibly small radial velocity, was located within the inscribing radius of the oval flow core. The vortex region was located outside the circumscribing radius of the oval flow core. The buffer region existed between the solid-body-rotation-like region and the vortex region. In the buffer region, there existed a “node” point that the propagating circumferential velocity waves diminished. The circumferential random fluctuation intensity presented minimum values at the node point and high values in the solid-body-rotation-like region and shroud-influenced region due to the shear effect induced by the wall.
Simulation of Phase Transition During Cryosurgical Treatment of a Tumor Tissue Loaded With Nanoparticles Using Meshfree Approach
Authors: Singh Sonam , Bhargava R.
Published: October 2014

In medical world, the minimally invasive freezing therapy or cryosurgery is an efficacious treatment for complete and controlled eradication of tumor cells. Many difficulties are encountered in cryosurgery process such as inappropriate freezing may not completely destroy the target tumor tissue and excessive freezing may harm the surrounding healthy tissues due to release of high amount of cold from the freezing probe. In present study, the target tumor tissue is loaded with nanoparticles in order to improve the freezing capacity of probe and to regulate the orientation and size of ice-ball formed during cryosurgery. In this process, phase transformation occurs in the undesired tumor tissues. For simulation of phase transition in bio heat transfer equation, the fixed-domain, heat capacity method is used to take into account the latent heat of phase change. In this study, a meshfree numerical technique known as element free Galerkin method (EFGM) is employed to simulate the phase transition and temperature field for a biological tissue subjected to nanocryosurgery. The latest nanofluid model which includes the effects of particles size, concentration, and the interfacial layer at the particle/liquid interface is utilized and their impact on freezing process is investigated in detail.
Airgap Statistics for a Tension Leg Platform
Authors: Gaidai Oleg , Naess Arvid , Stansberg Carl Trygve
Published: October 2014

The paper discusses a method for estimating extreme value statistics of the airgap for floating offshore platforms subjected to random seas. It is an adaptation of a recently developed method, which is based on the mean upcrossing rate (MUR) function for univariate time series combined with an optimization procedure that allows prediction at extreme response levels by extrapolation. Extensive model tests were performed in a large wave basin for a tension leg platform (TLP) operating in the Norwegian Sea. Among several critical parameters, the airgap was measured at a number of locations under the platform deck. The wave in deck impact is a critical safety issue with respect to the deck damage and occurrence of extreme tether tensions. The authors have utilized experimental data to look at critical airgaps under the deck in random waves. Conclusions are drawn about extreme airgap statistics, and consequently about the wave impact probability in severe seas.
Simulation of Stress Corrosion Cracking in In-Core Monitor Housing of Nuclear Power Plant
Authors: Shintaku Yuichi , Iwamatsu Fuminori , Suga Kazuhiro , Wada Yoshitaka , Kikuchi Masanori
Published: October 2014

In the in-core monitor (ICM) housing of a reactor pressure vessel (RPV), residual stress has been widely reported to cause stress corrosion cracking (SCC) damage in the weld heat-affected zone. For this reason, it is important to evaluate the crack growth conservatively, and with high confidence to demonstrate fitness for service. This paper presents crack growth simulations in an ICM housing, which is welded at two different angles to the RPV. One weld angle is at the bottom of the RPV, and the welding area of the ICM housing is axisymmetric. The other angle is at the curved position of the RPV, and the weld area of the ICM housing is asymmetric. In these weld areas, crack growth behavior is estimated by superposed-finite element method (S-FEM), which allows generation of a global finite model and a detailed local mesh representing the crack independently. In the axisymmetric weld area, axial, slant and circumferential surface cracks are assumed at two locations where the residual stress fields are different from each other: one is isotropic and the other is circumferential. It is shown that crack growth behaviors are different under different residual stress fields. The results of S-FEM are compared with those of the influence function method (IFM), which assumes that an elliptical crack shape exists in a plate. It is shown that the IFM result is conservative compared to that of S-FEM. Next, an axial surface crack is assumed at the uphill, downhill, and midhill asymmetric weld areas. The midhill crack growth behavior is different from the uphill and downhill behaviors. Finally, two surface cracks are simulated in the asymmetric weld area and two initial crack arrangements are assumed. These results show the differences of the crack interaction and the crack growth process.
A Transonic Mixed Flow Compressor for an Extreme Duty
Authors: Hazby Hamid , Casey Michael , Numakura Ryusuke , Tamaki Hideaki
Published: October 2014

This paper describes the design of a transonic mixed flow compressor stage for an extreme duty, with an extremely high flow coefficient (φ) of 0.25 and a high isentropic pressure rise coefficient (ψ) of 0.56. The impeller design makes use of modern aerodynamic practice from radial and transonic axial compressors, whereby the aerodynamic blade shape involved arbitrary surfaces on several spanwise sections. Some aspects of the aerodynamic optimization of the design were limited by mechanical considerations, but nevertheless the test data obtained on a prototype stage demonstrates that acceptable performance levels can be achieved at these extreme design conditions, although map width enhancement (MWE) devices were needed to obtain an acceptable operating range. The test data are compared with computational fluid dynamics (CFD) predictions to demonstrate the validity of the design methods used.
Particle Image Velocimetry Measurements in a Two-Pass 90 Degree Ribbed-Wall Parallelogram Channel
Authors: Liou Tong-Miin , Chang Shyy-Woei , Chan Shu-Po , Liu Yu-Shuai
Published: October 2014

A parallelogram channel has drawn very little or no attention in the open literature although it appears as a cross-sectional configuration of some gas turbine rotor blades. Particle image velocimetry (PIV) is presented of local flow structure in a two-pass 90 deg ribbed-wall parallelogram channel with a 180 deg sharp turn. The channel has a cross-sectional equal length, 45.5 mm, of adjacent sides and two pairs of opposite angles are 45 deg and 135 deg. The rib height to channel height ratio is 0.1. All the measurements were performed at a fixed Reynolds number, characterized by channel hydraulic diameter of 32.17 mm and cross-sectional bulk mean velocity, of 10,000 and a null rotating number. Results are discussed in terms of the distributions of streamwise and secondary-flow mean velocity vector, turbulent intensity, Reynolds stress, and turbulent kinetic energy of the cooling air. It is found that the flow is not periodically fully developed in pitchwise direction through the inline 90 deg ribbed straight inlet and outlet leg. Pitchwise variation of reattachment length is revealed, and comparison with reported values in square channels is made. Whether the 180 deg sharp turn induced separation bubble exists in the ribbed parallelogram channel is also documented. Moreover, the measured secondary flow results inside the turn are successively used to explain previous heat transfer trends.
Rotor Blade Heat Transfer of High Pressure Turbine Stage Under Inlet Hot-Streak and Swirl
Authors: Rahim A. , He L.
Published: October 2014

A key consideration in high pressure (HP) turbine designs is the heat load experienced by rotor blades. Impact of turbine inlet nonuniformity of combined temperature and velocity traverses, typical for a lean-burn combustor exit, has rarely been studied. For general turbine aerothermal designs, it is also of interest to understand how the behavior of lean-burn combustor traverses (with both hot-streak and swirl) might contrast with those for a rich-burn combustor (largely hot-streak only). In the present work, a computational study has been carried out on the aerothermal performance of a HP turbine stage under nonuniform temperature and velocity inlet profiles. The analyses are primarily conducted for two combined hot-streak and swirl inlets, with opposite swirl directions. In addition, comparisons are made against a hot-streak only case and a uniform inlet. The effects of three nozzle guide vane (NGV) shape configurations are investigated: straight, compound lean (CL) and reverse CL (RCL). The present results reveal a qualitative change in the roles played by heat transfer coefficient (HTC) and fluid driving (“adiabatic wall”) temperature, Taw. It has been shown that the blade heat load for a uniform inlet is dominated by HTC, whilst a hot-streak only case is largely influenced by Taw. However, in contrast to the hot-streak only case, a combined hot-streak and swirl case shows a role reversal with the HTC being a dominant factor. Additionally, it is seen that the swirling flow redistributes radially the hot fluid within the NGV passage considerably, leading to a much ‘flatter’ rotor inlet temperature profile compared to its hot-streak only counterpart. Furthermore, the rotor heat transfer characteristics for the combined traverses are shown to be strongly dependent on the NGV shaping and the inlet swirl direction, indicating a potential for further design space exploration. The present findings underline the need to clearly define relevant combustor exit temperature and velocity profiles when designing and optimizing NGVs for HP turbine aerothermal performance.
Second Law Analysis of Integrated Solar Combined Cycle Power Plants
Authors: Gülen S. Can
Published: October 2014

Integrated solar combined cycle (ISCC) is an operationally simple, clean electric power generation system that is economically more attractive vis-à-vis stand-alone concentrating solar power (CSP) technology. The ISCC can be designed to achieve two primary goals: (1) replace natural gas combustion with solar thermal power at the same output rating to reduce fuel consumption and stack emissions and/or (2) replace supplementary (duct) firing in the heat recovery steam generator (HRSG) with “solar firing” to boost power generation on hot days. Optimal ISCC design requires a seamless integration of the solar thermal and fossil-thermal technologies to maximize the solar contribution to the overall system performance at the lowest possible size and cost. The current paper uses the exergy concept of the second law of thermodynamics to distill the quite complex optimization problem to its bare essentials. The goal is to provide the practitioners with physics-based, user-friendly guidelines to understand the key drivers and the interaction among them. Ultimately, such understanding is expected to help direct studies involving heavy use of time consuming system models in a focused manner and evaluate the results critically to arrive at feasible ISCC designs.
Evidence for direct molecular oxygen production in CO
2
photodissociation
Authors: Lu Zhou , Chang Yih Chung , Yin Qing-Zhu , Ng C. Y. , Jackson William M.
Published: October 2014

Illuminating oxygen out of carbon dioxide

It has long been known that high-energy ultraviolet light can split carbon dioxide into CO and O fragments. Lu
et al.
have now uncovered a parallel pathway that appears to yield C and O
2
instead (see the Perspective by Suits and Parker). By precisely measuring the energy and trajectory of the carbon fragment after CO
2
irradiation, O
2
formation could be inferred. The results introduce a potential mechanism for abiotic oxygen production in CO
2
-heavy atmospheres of other planets.

Science
, this issue p.
61
; see also p.
30
A neighborhood watch upholds local immune protection
Authors: Carbone Francis R. , Gebhardt Thomas
Published: October 2014

T cells that reside in peripheral tissue create conditions that enable local and broad responses to infection

[Also see Reports by
Iijima and Iwasaki
,

Schenkel
et al.

and

Ariotti
et al.

]
How large predators manage the cost of hunting
Authors: Laundré John W.
Published: October 2014

For pumas and cheetahs, seeking prey is more energetically costly than the subsequent chase

[Also see Reports by

Scantlebury
et al.

and

Williams
et al.

]
Rewriting the genome: Even DNA needs an editor
Authors: Perkel Jeffrey M.
Published: October 2014

Until relatively recently, the power of molecular biology was at once vast and limited. Researchers who wanted to knock out specific genes to see what they did mostly had to restrict such studies to mice, and specific strains at that. Now a new class of genome- and epigenome-editing tools is reshaping the landscape. From Arabidopsis to humans to zebrafish, researchers are finding that, generally speaking, when it comes to the genome, if they can dream it, they can build it.
Multicultural relationships: Working across cultures and countries
Authors: Tachibana Chris
Published: October 2014

Like travel writers and diplomats, scientists have tremendous opportunities for international interactions. Researchers can train abroad and attend conferences all over the world. The academic sabbatical is a chance to experience a foreign land while maintaining domestic roots. Hosting a guest scientist from another country can bring fresh perspectives to a research group. Cross-border professional relationships require cultivation, though. This feature offers advice from experienced scientists on the whys and hows of international collaborations.
The littlest patient
Authors: Couzin-Frankel Jennifer
Published: October 2014

Cutting-edge mouse models fuel hope for understanding and treating cancer.
Human Astroviruses
Authors: Bosch Albert , Pintó Rosa M. , Guix Susana
Published: October 2014

Human astroviruses (HAtVs) are positive-sense single-stranded RNA viruses that were discovered in 1975. Astroviruses infecting other species, particularly mammalian and avian, were identified and classified into the generaMamastrovirusandAvastrovirus. Through next-generation sequencing, many new astroviruses infecting different species, including humans, have been described, and theAstroviridaefamily shows a high diversity and zoonotic potential. Three divergent groups of HAstVs are recognized: the classic (MAstV 1), HAstV-MLB (MAstV 6), and HAstV-VA/HMO (MAstV 8andMAstV 9) groups. Classic HAstVs contain 8 serotypes and account for 2 to 9% of all acute nonbacterial gastroenteritis in children worldwide. Infections are usually self-limiting but can also spread systemically and cause severe infections in immunocompromised patients. The other groups have also been identified in children with gastroenteritis, but extraintestinal pathologies have been suggested for them as well. Classic HAstVs may be grown in cells, allowing the study of their cell cycle, which is similar to that of caliciviruses. The continuous emergence of new astroviruses with a potential zoonotic transmission highlights the need to gain insights on their biology in order to prevent future health threats. This review focuses on the basic virology, pathogenesis, host response, epidemiology, diagnostic assays, and prevention strategies for HAstVs.
Controlling Hospital-Acquired Infection: Focus on the Role of the Environment and New Technologies for Decontamination
Authors: Dancer Stephanie J.
Published: October 2014

There is increasing interest in the role of cleaning for managing hospital-acquired infections (HAI). Pathogens such as vancomycin-resistant enterococci (VRE), methicillin-resistant
Staphylococcus aureus
(MRSA), multiresistant Gram-negative bacilli, norovirus, and
Clostridium difficile
persist in the health care environment for days. Both detergent- and disinfectant-based cleaning can help control these pathogens, although difficulties with measuring cleanliness have compromised the quality of published evidence. Traditional cleaning methods are notoriously inefficient for decontamination, and new approaches have been proposed, including disinfectants, steam, automated dispersal systems, and antimicrobial surfaces. These methods are difficult to evaluate for cost-effectiveness because environmental data are not usually modeled against patient outcome. Recent studies have reported the value of physically removing soil using detergent, compared with more expensive (and toxic) disinfectants. Simple cleaning methods should be evaluated against nonmanual disinfection using standardized sampling and surveillance. Given worldwide concern over escalating antimicrobial resistance, it is clear that more studies on health care decontamination are required. Cleaning schedules should be adapted to reflect clinical risk, location, type of site, and hand touch frequency and should be evaluated for cost versus benefit for both routine and outbreak situations. Forthcoming evidence on the role of antimicrobial surfaces could supplement infection prevention strategies for health care environments, including those targeting multidrug-resistant pathogens.
Clinical Microbiology Informatics
Authors: Rhoads Daniel D. , Sintchenko Vitali , Rauch Carol A. , Pantanowitz Liron
Published: October 2014

The clinical microbiology laboratory has responsibilities ranging from characterizing the causative agent in a patient's infection to helping detect global disease outbreaks. All of these processes are increasingly becoming partnered more intimately with informatics. Effective application of informatics tools can increase the accuracy, timeliness, and completeness of microbiology testing while decreasing the laboratory workload, which can lead to optimized laboratory workflow and decreased costs. Informatics is poised to be increasingly relevant in clinical microbiology, with the advent of total laboratory automation, complex instrument interfaces, electronic health records, clinical decision support tools, and the clinical implementation of microbial genome sequencing. This review discusses the diverse informatics aspects that are relevant to the clinical microbiology laboratory, including the following: the microbiology laboratory information system, decision support tools, expert systems, instrument interfaces, total laboratory automation, telemicrobiology, automated image analysis, nucleic acid sequence databases, electronic reporting of infectious agents to public health agencies, and disease outbreak surveillance. The breadth and utility of informatics tools used in clinical microbiology have made them indispensable to contemporary clinical and laboratory practice. Continued advances in technology and development of these informatics tools will further improve patient and public health care in the future.
Cryptococcus gattii Infections
Authors: Chen Sharon C.-A. , Meyer Wieland , Sorrell Tania C.
Published: October 2014

Understanding of the taxonomy and phylogeny ofCryptococcus gattiihas been advanced by modern molecular techniques.C. gattiiprobably diverged fromCryptococcus neoformansbetween 16 million and 160 million years ago, depending on the dating methods applied, and maintains diversity by recombining in nature. South America is the likely source of the virulentC. gattiiVGII molecular types that have emerged in North America.C. gattiishares major virulence determinants withC. neoformans, although genomic and transcriptomic studies revealed that despite similar genomes, the VGIIa and VGIIb subtypes employ very different transcriptional circuits and manifest differences in virulence phenotypes. Preliminary evidence suggests thatC. gattiiVGII causes severe lung disease and death without dissemination, whereasC. neoformansdisseminates readily to the central nervous system (CNS) and causes death from meningoencephalitis. Overall, currently available data indicate that theC. gattiiVGI, VGII, and VGIII molecular types more commonly affect nonimmunocompromised hosts, in contrast to VGIV. New, rapid, cheap diagnostic tests and imaging modalities are assisting early diagnosis and enabling better outcomes of cerebral cryptococcosis. Complications of CNS infection include increased intracranial pressure, severe neurological sequelae, and development of immune reconstitution syndrome, although the mortality rate is low.C. gattiiVGII isolates may exhibit higher fluconazole MICs than other genotypes. Optimal therapeutic regimens are yet to be determined; in most cases, initial therapy with amphotericin B and 5-flucytosine is recommended.
Efficient Diagnosis and Treatment Follow-Up of Human Brucellosis by a Novel Quantitative TaqMan Real-Time PCR Assay: a Human Clinical Survey
Authors: Sohrabi Majid , Mohabati Mobarez Ashraf , Khoramabadi Nima , Hosseini Doust Reza , Behmanesh Mehrdad
Published: October 2014

Rapid and effective diagnosis of brucellosis is a challenge for clinicians. Even when diagnosis is on time and therapy is initiated, meticulous follow-up appointments are crucial for ensuring the efficacy of the treatment. Due to shortcomings of serological methods, molecular diagnosis, especially real-time PCR, is becoming a main approach in laboratory diagnostics. Thus, the development of efficient procedures and standardization of the PCR tests will have a great impact on the precise detection and quantification of bacterial DNA loads, which is valuable for the medical management of brucellosis patients. We developed a new TaqMan real-time PCR directed tobcsp31, a shared gene of the brucellae. Thebcsp31gene fragment was cloned into pJET1.2. Recombinant pJET1.2-bcsp31was linearized by HindIII digestion, and the product was used for the preparation of a standard curve. A panel ofBrucellaspp. and non-Brucellapathogens was tested. No bacterial genomes other than those of the brucellae were detected. According to the results, specificity of the method was 100%. In a clinical assessment, the positive-control group comprised 37 patients with microbiologically confirmed brucellosis, and 25 healthy individuals served as the negative-control group. By the end of the treatment period, there was a significant decrease in the DNA load of the 37 brucellosis patients, which persisted for the 4 weeks of monitoring after treatment, suggesting that our proposed method is an efficient monitoring tool. Serum samples prior to any treatment were collected from the 25 serologically suspicious patients and assessed by our method; 72% of these patients tested positive for brucellosis.