bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison between two types of improved motion‐sensitized driven‐equilibrium (iMSDE) for intracranial black‐blood imaging at 3.0 tesla
Authors: Obara Makoto , Kuroda Kagayaki , Wang Jinnan , Honda Masatoshi , Yoneyama Masami , Imai Yutaka , Van Cauteren Marc 
Published: November 2013

PurposeTo investigate the image quality impact of a new implementation of the improved motion‐sensitized driven‐equilibrium (iMSDE) pulse scheme in the human brain at 3.0 Tesla.Materials and MethodsTwo iMSDE preparation schemes were compared; (a) iMSDE‐1: two refocusing pulses and two pairs of bipolar gradients and (b) iMSDE‐2: adding extra bipolar gradients in front of the iMSDE‐1 preparation. Computer simulation was used to evaluate the difference of eddy currents effect between these two approaches. Five healthy volunteers were then scanned with both sequences in the intracranial region and signal changes associated with iMSDE‐1 and iMSDE‐2 were assessed and compared quantitatively and qualitatively.ResultsSimulation results demonstrated that eddy currents are better compensated in iMSDE‐2 than in the iMSDE‐1 design. In vivo comparison showed that the iMSDE‐2 sequence significantly reduced the tissue signal loss at all locations compared with iMSDE‐1 (5.0% versus 23% in average, P < 0.0002 at paired t‐test). The signal in iMSDE‐1 showed greater spatial inhomogeneity than that of iMSDE‐2.ConclusionOur results show that iMSDE‐2 demonstrated smaller loss in signal and less spatial variation compared with iMSDE‐1, we conjecture due to the improved eddy current compensation. J. Magn. Reson. Imaging 2014;40:824–831. © 2013 Wiley Periodicals, Inc.
Longitudinal anatomical and metabolic MRI characterization of orthotopic xenograft prostate tumors in nude mice
Authors: Mallett Christiane L. , Lim Heeseung , Thind Kundan , Chen Yuhua , Ribot Emeline J. , Martinez Francisco , Scholl Timothy J. , Foster Paula J. 
Published: November 2013

PurposeTo assess anatomic and functional magnetic resonance imaging (MRI) for monitoring of tumor volume and metabolism of orthotopic xenograft prostate cancer tumors.Materials and MethodsHuman‐derived PC‐3M cells were implanted into the prostate in 22 nude mice. Tumor volume and MRI appearance were monitored for up to 29 days. Histology was performed to detect metastases. Hyperpolarized [1‐13C]pyruvate MRI was used to measure tumor metabolism on day 22.ResultsTumors were visible by MRI 9 days after tumor cell implantation. Tumor volume increased to 720 ± 190 mm3 on day 29 of imaging. Metastasis was seen in the iliac lymph nodes at all timepoints, and in more distant lymph nodes at later timepoints, but was not detectable by MRI. Regions with low pyruvate uptake corresponded to regions with necrosis and had a higher lactate/pyruvate ratio (0.98 ± 0.4 vs. 1.6 ± 1.1).ConclusionMRI using the balanced steady‐state free precession (bSSFP) sequence can be used to monitor tumor growth in orthotopic PC‐3M tumors as early as 9 days post‐injection. Hyperpolarized pyruvate MRI has potential to assess tumor metabolism and necrosis. J. Magn. Reson. Imaging 2014;40:848–856. © 2013 Wiley Periodicals, Inc.
Air temperature distribution over Mongolia using dynamical downscaling and statistical correction
Authors: Gerelchuluun Bayasgalan , Ahn Joong‐Bae 
Published: November 2013

ABSTRACTIn this study, dynamical downscaling was performed using the Weather Research and Forecast (WRF) model to attain fine‐resolution gridded meteorological information capable of reflecting Mongolia's complex topographical effect. Mongolia's sparse station network, with an average inter‐station distance 107 km, is incapable of representing the spatial distribution of climate variables, such as temperature, over the country's complex topography. In order to reproduce fine‐scale air temperature in Mongolia, the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis II data with 6‐h intervals from 1981 to 2010 were used as the initial and boundary conditions of the WRF model. A one‐way nesting system was applied for two nested domains with horizontal grid spaces of 60 and 20 km. For correction of the systematic biases induced by dynamical downscaling, a statistical correction method was used for the downscaled results simulated by the WRF model. The bias was divided into two parts: the mean and the perturbation. The former was corrected by using a weighting function and a temperature inversion, and the latter by using the self‐organizing maps method. In the former correction, the temperature inversion, characterized by an inverted lapse rate, in which temperature increases with increasing height in the lower atmosphere, was considered only when the temperature inversion occurred. According to our result, the domain‐averaged Root Mean Square Difference of the model‐simulated annual mean temperature was decreased from 3.7 °C to 2.1 °C after the statistical and temperature inversion corrections. On the basis of our study, we suggested that the area‐averaged, fine‐resolution, annual mean temperature of Mongolia was 1.1 °C (station mean temperature 0.5 °C). Our correction method improves not only spatial patterns with fine resolution but also the time‐varying temperature variance over Mongolia.
Atmospheric modulations of the ratio of UVB to broadband solar radiation: effect of ozone, water vapour, and aerosols at Qena, Egypt
Authors: Adam M. El‐Nouby 
Published: November 2013

ABSTRACTThis study is an attempt to assess atmospheric modulations of the radiometric ratio of ultraviolet‐B (UVB) to broadband solar radiation (G). It examines the role of the atmosphere as a filter, absorbing and scattering portions of the solar spectrum, shielding the biosphere from damaging doses of UVB. The diurnal variability of UVB/G at the Earth's surface has been evaluated by analysing 10‐year hourly measurements of UVB and G on a horizontal surface at Qena, Egypt. The results show that, throughout the whole period, the values of hourly UVB/G varied from 0.03 to 0.73%, with an average value of 0.27%. This average represents only 17% of the corresponding value outside the atmosphere (1.56%). Moreover, the study quantifies the impact of ozone, water vapour, and aerosols on UVB/G under cloudless conditions. An analysis of the relationship between this ratio and the slant total ozone column (Z) was also carried out. It showed that the ratio decreased with increasing Z. For Z = 537 DU, the average UVB/G was almost 53.47% lower than that at low Z (277 DU). The influence of precipitable water (W) on UVB/G was determined under limited change in Z (<8.72%) and almost constant turbidity level (Ångström turbidity coefficient, β, of 0.19). The values of UVB/G increased with increasing W. For an average W = 1.13 cm, the average UVB/G was approximately 3.93% lower than at high W (2.82 cm). Moreover, the study illustrated the effect of aerosols on UVB/G when their influence on this ratio is greater than the impact of other atmospheric factors such as ozone and water vapour. It can be concluded that the ratio of the change in UVB/G to the change in β varies from 0.16 to 0.59%, with an average value of 0.33%.
Optimisation of the critical medium components for better growth of Picochlorum sp. and the role of stressful environments for higher lipid production
Authors: Dahmen Ines , Chtourou Haifa , Jebali Ahlem , Daassi Dhouha , Karray Fatma , Hassairi Ilem , Sayadi Sami , Abdelkafi Slim , Dhouib Abdelhafidh 
Published: November 2013

AbstractBACKGROUNDCoastal countries that suffer from a scarcity of water, such as Tunisia, have to cultivate marine microalgae on non‐arable land in order to produce feedstock and overcome their demands of nutrition and energy. In this framework, a green microalga, CTM 20019, was isolated, identified as Picochlorum sp. and tested for its lipid production.RESULTSThe dry weight of Picochlorum sp. is composed of 163 g kg−1 lipids, 225 g kg−1 total sugars, 440 g kg−1 proteins and 112 g kg−1 ash rich in potassium, calcium, iron, magnesium and zinc. Gas chromatography–mass spectrometry analysis showed that the main fatty acids were palmitic acid (29%), linolenic acid (26.5%), linoleic acid (23.5%), hexadecatrienoic acid (11%) and hexadecadienoic acid (8.5%). As it is known that culture conditions greatly influence the composition of microalgae, the experiments were designed to optimise the composition of the medium in order to increase Picochlorum sp. growth from OD680nm = 0.53 to OD680nm = 2.2 and lipid accumulation from 163 g kg−1 to 190 g kg−1. The highest lipid contents of 570 and 585 g kg−1 were achieved under phosphate starvation and sodium carbonate supplementation, respectively. Under these conditions, the fatty acid profile is dominated by mono‐unsaturated and polyunsaturated acids, and is therefore suitable for aqua‐culture feeding. However, under high salinity, growth and lipid synthesis are inhibited, and the fatty acids are saturate, and the product is therefore suitable for biodiesel.CONCLUSIONThis high lipid content rich in essential fatty acids, omega‐6 and omega‐3, endorses this wild strain of Picochlorum sp. as a promising feedstock for aqua‐culture and human nutrition or for the production of biodiesel. © 2013 Society of Chemical Industry
Laser Cutting of Carbon Fibres
Authors: Bliedtner Jens , Remdt Sebastian , Müller Hartmut , Petrich Andreas 
Published: November 2013

AbstractCarbon and glass fibre fabrics are mostly cut using mechanic cutting tools. The disadvantage, however, is that these tools wear out fast. The contact‐free cutting by means of a laser beam provides a good alternative. In the conventional laser cutting the fibre ends do not stick together which means the cutting edge is not sealed and so the coherence within the fabric structure can no longer be guaranteed. Thus a further automated processing of the fabric cut‐outs is only possible to a limited extent. This article introduces a procedure by which a sealing of the cutting edges can be achieved during the cutting process.
Directed Multiobjective Optimization Based on the Weighted Hypervolume Indicator
Authors: Brockhoff Dimo , Bader Johannes , Thiele Lothar , Zitzler Eckart 
Published: November 2013

ABSTRACTRecently, there has been a large interest in set‐based evolutionary algorithms for multi objective optimization. They are based on the definition of indicators that characterize the quality of the current population while being compliant with the concept of Pareto‐optimality. It has been shown that the hypervolume indicator, which measures the dominated volume in the objective space, enables the design of efficient search algorithms and, at the same time, opens up opportunities to express user preferences in the search by means of weight functions. The present paper contains the necessary theoretical foundations and corresponding algorithms to (i) select appropriate weight functions, to (ii) transform user preferences into weight functions and to (iii) efficiently evaluate the weighted hypervolume indicator through Monte Carlo sampling. The algorithm W‐HypE, which implements the previous concepts, is introduced, and the effectiveness of the search, directed towards the user's preferred solutions, is shown using an extensive set of experiments including the necessary statistical performance assessment. Copyright © 2013 John Wiley & Sons, Ltd.
Indicator‐based Selection in Evolutionary Multiobjective Optimization Algorithms Based On the Desirability Index
Authors: Trautmann Heike , Wagner Tobias , Biermann Dirk , Weihs Claus 
Published: November 2013

ABSTRACTIn multiobjective optimization, the identification of practically relevant solutions on the Pareto‐optimal front is an important research topic. Desirability functions (DFs) allow the preferences of the decision maker to be specified in an intuitive way. Recently, it has been shown for continuous optimization problems that an a priori transformation of the objectives by means of DFs can be used to focus the search of a hypervolume‐based evolutionary algorithm on the desired part of the front. In many‐objective optimization, however, the computational complexity of the hypervolume can become a crucial part. Thus, an alternative to this approach will be presented in this paper. The new algorithm operates in the untransformed objective space, but the desirability index (DI), that is, a DF‐based scalarization, will be used as the second‐level selection criterion in the non‐dominated sorting. The diversity and uniform distribution of the resulting approximation are ensured by the use of an external archive. In the experiments, different preferences are specified as DFs, and their effects are investigated. It is shown that trade‐off solutions are generated in the desired regions of the Pareto‐optimal front and with a density adaptive to the DI. The efficiency of the approach with respect to increasing objective space dimension is also analysed using scalable test functions. The convergence speed is superior to other set‐based and preference‐based evolutionary multiobjective algorithms while the approach is of low computational complexity due to cheap DI evaluations. Copyright © 2013 John Wiley & Sons, Ltd.
A Thin‐layer Chromatography Autographic Method for the Detection of Inhibitors of the Salmonella PhoP–PhoQ Regulatory System
Authors: Salazar Mario O. , Viarengo Gaston , Sciara Mariela I. , Kieffer Pablo M. , Garcia Vescovi Eleonora , Furlan Ricardo L. E. 
Published: November 2013

ABSTRACTIntroductionThe PhoP–PhoQ system from Salmonella enterica serovar Typhimurium controls the expression of factors that are critical for the bacterial entry into host cells and the bacterial intramacrophage survival. Therefore it constitutes an interesting target to search for compounds that would control Salmonella virulence. Localisation of such compounds in complex matrixes could be facilitated by thin‐layer chromatography (TLC) bioautography.ObjectiveTo develop a TLC bioautography to detect inhibitors of the PhoP–PhoQ regulatory system in complex matrixes.MethodsThe TLC plates were covered by a staining solution containing agar, Luria‐Bertani medium, 5‐bromo‐4‐chloro‐3‐indolyl‐β‐D‐galactopyranoside (X‐gal), kanamycin and a S. typhimurium strain that harbours a reporter transcriptional lacZ‐fusion to an archetypal PhoP‐activated gene virK. After solidification, the plate was incubated at 37°C for 16 h.ResultsA bioautographic assay suitable for the localisation of inhibitors of the PhoP–PhoQ system activity in S. enterica serovar Typhimurium present in a complex matrix is described. The assay was used to analyse a series of hydrolysed extracts prepared by alkaline treatment of crude plant extracts. Bioassay‐guided analysis of the fractions by NMR spectroscopy and MS led to the identification of linolenic and linoleic acids as inhibitory input signals of the PhoP–PhoQ system.ConclusionA practical tool is introduced that facilitates detection of inhibitors of the Salmonella PhoP–PhoQ regulatory system. The assay convenience is illustrated with the identification of the first naturally occurring organic compounds that down‐regulate a PhoP–PhoQ regulatory system from a hydrolysed extract. Copyright © 2013 John Wiley & Sons, Ltd.
Erhellendes über den Dunkelstrom
Authors: Breitenstein Otwin 
Published: November 2013

AbstractSolarzellen aus kristallinen Silizium‐ Wafern sind heute das Arbeitspferd der Photovoltaik. 88 % aller weltweit produzierten Solarmodule enthalten solche Zellen, 57 % entfallen auf multikristalline Solarzellen. Diese sind günstiger als monokristalline Solarzellen herzustellen, haben aber einen 1 bis 2 % niedrigeren Wirkungsgrad. Bis vor kurzem waren die Ursachen noch nicht vollständig verstanden. Erst der Einsatz neuer bildgebender Analysemethoden wie Lock‐in‐Thermographie und Lumineszenz‐Abbildung führte zu einem tieferen Verständnis. Entscheidend für die Verluste sind Korngrenzen und andere Defekte, etwa Kratzer, sowie Verunreinigungen durch Fremdmetalle. Neue Herstellungsprozesse können diese Fehlerquellen verringern.
A simple colony‐formation assay in liquid medium, termed ‘tadpoling’, provides a sensitive measure of Saccharomyces cerevisiae culture viability
Authors: Welch Aaron Z. , Koshland Douglas E. 
Published: November 2013

AbstractHere we describe the first high‐throughput amenable method of quantifying Saccharomyces cerevisiae culture viability. Current high‐throughput methods of assessing yeast cell viability, such as flow cytometry and SGA analysis, do not measure the percentage viability of a culture but instead measure cell vitality or colony fitness, respectively. We developed a method, called tadpoling, to quantify the percentage viability of a yeast culture, with the ability to detect as few as one viable cell amongst ~108 dead cells. The most important feature of this assay is the exploitation of yeast colony formation in liquid medium. Utilizing a microtiter dish, we are able to observe a range of viability of 100% to 0.0001%. Comparison of tadpoling to the traditional plating method to measure yeast culture viability reveals that, for the majority of Saccharomyces species analyzed there is no significant difference between the two methods. In comparison to flow cytometry using propidium iodide, the high‐throughput method of measuring yeast culture viability, tadpoling is much more accurate at culture viabilities < 1%. Thus, we show that tadpoling provides an easy, inexpensive, space‐saving method, amenable to high‐throughput screens, for accurately measuring yeast cell viability. Copyright © 2013 John Wiley & Sons, Ltd.
RELATIVISM, KNOWLEDGE AND UNDERSTANDING
Authors: Carter J. Adam 
Published: November 2013

AbstractThe arguments for and against a truth-relativist semantics for propositional knowledge attributions (KTR) have been debated almost exclusively in the philosophy of language. But what implications would this semantic thesis have in epistemology? This question has been largely unexplored. The aim of this paper is to establish and critique several ramifications of KTR in mainstream epistemology. The first section of the paper develops, over a series of arguments, the claim that MacFarlane's (2005, 2010) core argument for KTR ultimately motivates (for better or worse) the extension of a truth-relativist semantics to a subset of understanding attributions – attributions ofunderstanding-why. I conclude by presenting some reasons to think thateven ifKTR were otherwise plausible, a truth-relativist semantics for understanding-why attributions is not. These claims, taken together, constitute a kind of epistemological argument against MacFarlane-style truth-relativism for knowledge attributions.
WHEN THE EXPERTS ARE UNCERTAIN: SCIENTIFIC KNOWLEDGE AND THE ETHICS OF DEMOCRATIC JUDGMENT
Authors: Lane Melissa 
Published: November 2013

AbstractCan ordinary citizens in a democracy evaluate the claims of scientific experts? While a definitive answer must be case by case, some scholars have offered sharply opposed general answers: a skeptical “no” (e.g. Scott Brewer) versus an optimistic “yes, no problem” (e.g. Elizabeth Anderson). The article addresses this basic conflict, arguing that a satisfactory answer requires a first-order engagement in judging the claims of experts which both skeptics and optimists rule out in taking the issue to be one of second-order assessments only. Having argued that such first-order judgments are necessary, it then considers how they are possible, outlining a range of practices and virtues that can inform their success and likelihood, and drawing throughout on ancient Greek insights as well as contemporary social psychology and sociology of knowledge. In conclusion the ethics of democratic judgment so developed is applied to the dramatic conviction of the members of an Italian scientific risk commission in L'Aquila.
Interaction of panel flutter with inviscid boundary layer instability in supersonic flow
Authors: Vedeneev Vasily 
Published: November 2013

AbstractWe investigate the stability of an elastic plate in supersonic gas flow. This problem has been studied in many papers regarding panel flutter, where uniform flow is usually considered. In this paper, we take the boundary layer on the plate into account and investigate its influence on plate stability. Three problem formulations are studied. First, we investigate the stability of travelling waves in an infinite-length plate. Second, the nature of the instability (absolute or convective instability) is examined. Finally, by using solutions of the first two problems, instability of a long finite-length plate is studied by using Kulikovskii’s global instability criterion. The following results are obtained. All the eigenmodes of a finite-length plate are split into two types, which we call subsonic and supersonic. The influence of the boundary layer on these eigenmodes can be of two kinds. First, for a generalized convex boundary layer profile (typical for accelerating flow), supersonic eigenmodes are stabilized by the boundary layer, whereas subsonic disturbances are destabilized. Second, for a profile with a generalized inflection point (typical for constant and decelerating flows), supersonic eigenmodes are destabilized in a thin boundary layer and stabilized in a thick layer; subsonic eigenmodes are damped. The correspondence between the influence of the boundary layer on panel flutter and the stability of the boundary layer over a rigid wall is established. Examples of stable boundary layer profiles of both types are given.
Steady analysis of transcritical flows in collapsible tubes with discontinuous mechanical properties: implications for arteries and veins
Authors: Siviglia A. , Toffolon M. 
Published: November 2013

AbstractWe study the conditions under which discontinuous mechanical properties of a collapsible tube can induce transcritical flows, i.e. the transition through the critical state where the speed index (analogous to the Mach or the Froude numbers for compressible and free surface flows, respectively) is one. Such a critical transition may strongly modify the flow properties, cause a significant reduction in the cross-sectional area of the tube, and limit the flow. General relationships are obtained for a short segment using a one-dimensional model under steady flow conditions. Marginal curves delimiting the transcritical regions are identified in terms of the speed index and the cross-sectional area ratio. Since there are many examples of such flows in physiology and medicine, we also analyse the specific case of prosthesis (graft or stent) implantation in blood vessels. We then compute transcritical conditions for the case of stiffness and reference area variations, considering a collapsible tube characterized by physiological parameters representative of both arteries and veins. The results suggest that variations in mechanical properties may induce transcritical flow in veins but is unrealistic in arteries.