bluuebunny/crossref_metadata_2025 huggingface dataset:
Cancer or No Cancer: The Influence of Trait Anxiety and Diagnosis on Quality of Life With Breast Cancer and Benign Disease: A Prospective, Longitudinal Study
Authors: Keyzer‐Dekker Claudia M. G. , de Vries Jolanda , Mertens Marlies C. , Roukema Jan A. , van der Steeg Alida F. W.
Published: May 2013

Background

High trait anxiety (HTA) causes an impaired quality of life (QOL) and fatigue in women with breast cancer (BC) and benign breast disease (BBD). We examined whether the lowered QOL was determined solely by the personality characteristic HTA or by the combination of personality and diagnosis.

Methods

In a prospective longitudinal study, women with BC (n = 152), BBD (n = 205), or gallstone disease (GD) before laparoscopic cholecystectomy (n = 128) were included. Questionnaires concerning trait anxiety (baseline), fatigue, and QOL were completed at baseline and at 6 months. Multivariate linear regression analysis was performed to analyze the predictors for QOL at 6 months.

Results

At 6 months QOL scores were increased in the GD group, especially in women without HTA. For women without HTA, in the BBD group the scores for fatigue and physical QOL had improved at 6 months, whereas in the BC group physical QOL and fatigue was impaired. Women with HTA scored unfavorably on fatigue and QOL. HTA was the most important factor influencing QOL.

Conclusions

The course of QOL and fatigue during follow‐up were significantly different for each diagnosis. Particularly HTA had a negative impact on QOL and fatigue. Especially the combination HTA and BC caused impaired QOL and fatigue. We recommend identifying women with BC and HTA and offer them a tailor‐made follow‐up protocol.
Imaging neonatal spontaneous pneumomediastinum using ultrasound
Authors: Jung Ah Young , Yang Ik , Go Hee Sun , Shin Su-Mi , Yoon Hye-Kyung , Woo Ji Young , Hong Hye-Suk , Kim Han Myun
Published: May 2013

Purpose

To evaluate the feasibility of ultrasound in detecting spontaneous pneumomediastinum in the neonatal intensive care unit (NICU) and illustrate the ultrasound features.

Methods

Among neonates with abnormal mediastinal radiolucency suspected on chest radiography, those referred for ultrasound examination within 2 days were included. Anterior mediastinal ultrasound was performed using a linear transducer (5–12 MHz) to determine the presence and location of abnormal air in the mediastinum. Clinical data for the neonates were also reviewed.

Results

On ultrasound, pneumomediastinum appeared as thick linear/curvilinear echogenic lines, some with posterior shadowing located between the anterior chest wall and thymus, in lateral margins of the thymus, between the thymus and the great vessels, and in the middle of the thymic parenchyma.

Conclusions

Using ultrasound, pneumomediastinum was easily visualized, and localization of the abnormal air accumulation was possible. Ultrasound may be used as a radiation-free supplementary imaging modality for neonates with abnormal mediastinal air.
Stability of Dye Dispersions in the Presence of Some Eco‐Friendly Dispersing Agents
Authors: Gharanjig H. , Gharanjig K. , Tafaghodi Sina
Published: May 2013

The stability of dye dispersions in the presence of ethoxylated sorbitan lauryl and oleyl esters were reported and compared with dye dispersions containing a conventional dispersing agent, i.e. naphthalene sulfonic acid methylene‐bis sodium salt (NSAB). The optimum operating conditions obtained using a central composite design and stability of dye dispersions were evaluated by a turbidimetry method. Results showed that the dose of surfactants and the temperature of operation were important factors in preparing stable dye dispersions. Also, the best conditions for preparing dye dispersions were as follows: dose of surfactant 0.05 g, temperature 25 °C and time 5 min. In addition to, findings indicated that both of the used surfactants had better performance in dispersing the dyes in water. However, ethoxylated sorbitan oleate had better efficiency relative to other used dispersing agents. The performance of both sorbitan esters were compared with NSAB. The results indicated that they can create stable dye dispersions in aqueous media and have approximately the same effectiveness with NSAB. In this series, although oleate ester had a better performance than the laurate, the difference in performance of using dispersing agents was not significant. This finding was confirmed by the results of the particle size analysis of dye dispersions.
Balance model for equatorial long waves
Authors: Chan Ian H. , Shepherd Theodore G.
Published: May 2013

Geophysical fluid models often support both fast and slow motions. As the dynamics are often dominated by the slow motions, it is desirable to filter out the fast motions by constructing balance models. An example is the quasi-geostrophic (QG) model, which is used widely in meteorology and oceanography for theoretical studies, in addition to practical applications such as model initialization and data assimilation. Although the QG model works quite well in the mid-latitudes, its usefulness diminishes as one approaches the equator. Thus far, attempts to derive similar balance models for the tropics have not been entirely successful as the models generally filter out Kelvin waves, which contribute significantly to tropical low-frequency variability. There is much theoretical interest in the dynamics of planetary-scale Kelvin waves, especially for atmospheric and oceanic data assimilation where observations are generally only of the mass field and thus do not constrain the wind field without some kind of diagnostic balance relation. As a result, estimates of Kelvin wave amplitudes can be poor. Our goal is to find a balance model that includes Kelvin waves for planetary-scale motions. Using asymptotic methods, we derive a balance model for the weakly nonlinear equatorial shallow-water equations. Specifically we adopt the ‘slaving’ method proposed by Warn et al. (Q. J. R. Meteorol. Soc., vol. 121, 1995, pp. 723–739), which avoids secular terms in the expansion and thus can in principle be carried out to any order. Different from previous approaches, our expansion is based on a long-wave scaling and the slow dynamics is described using the height field instead of potential vorticity. The leading-order model is equivalent to the truncated long-wave model considered previously (e.g. Heckley & Gill, Q. J. R. Meteorol. Soc., vol. 110, 1984, pp. 203–217), which retains Kelvin waves in addition to equatorial Rossby waves. Our method allows for the derivation of higher-order models which significantly improve the representation of Rossby waves in the isotropic limit. In addition, the ‘slaving’ method is applicable even when the weakly nonlinear assumption is relaxed, and the resulting nonlinear model encompasses the weakly nonlinear model. We also demonstrate that the method can be applied to more realistic stratified models, such as the Boussinesq model.
Pattern prediction by linear analysis of turbulent flow with drag reduction by wall oscillation
Authors: Blesbois Olivier , Chernyshenko Sergei I. , Touber Emile , Leschziner Michael A.
Published: May 2013

A turbulent flow past a transverse-oscillating wall is considered. The oscillation parameters correspond to the regime where drag reduction is observed. Streak spacing and streak angle obtained from the generalized optimal perturbation approach are compared with results from direct numerical simulations. Other flow features of the generalized optimal perturbation are compared with conditionally-averaged data extracted from numerical simulations. The generalized optimal perturbation at a given instant in time is found to consist of an infinitely long structure at a certain angle to the main flow direction. This angle varies slowly with time for half a period, and then suddenly jumps to a different value, changing both sign and magnitude. The angle variation is shown to be slow, because there is a short time interval in the oscillation period when a small perturbation of a certain angle grows strongly and then remains dominant for almost the entire half-period. The transient growth mechanism of the generalized optimal perturbation is found to be a combination of the Orr mechanism due to the cross-flow shear, acting at the initial stage, followed by the lift-up mechanism of the velocity component directed along the structure by the wall-normal motion also oriented in the same direction.
Pressure losses in grooved channels
Authors: Mohammadi A. , Floryan J. M.
Published: May 2013

The effects of small-amplitude, two-dimensional grooves on pressure losses in a laminar channel flow have been analysed. Grooves with an arbitrary shape and an arbitrary orientation with respect to the flow direction have been considered. It has been demonstrated that losses can be expressed as a superposition of two parts, one associated with change in the mean positions of the walls and one induced by flow modulations associated with the geometry of the grooves. The former effect can be determined analytically, while the latter has to be determined numerically and can be captured with an acceptable accuracy using reduced-order geometry models. Projection of the wall shape onto a Fourier space has been used to generate such a model. It has been found that in most cases replacement of the actual wall geometry with the leading mode of the relevant Fourier expansion permits determination of pressure losses with an error of less than 10 %. Detailed results are given for sinusoidal grooves for the range of parameters of practical interest. These results describe the performance of arbitrary grooves with the accuracy set by the properties of the reduced-order geometry model and are exact for sinusoidal grooves. The results show a strong dependence of the pressure losses on the groove orientation. Longitudinal grooves produce the smallest drag, and oblique grooves with an inclination angle of ${\sim }42\textdegree $ exhibit the largest flow turning potential. Detailed analyses of the extreme cases, i.e. transverse and longitudinal grooves, have been carried out. For transverse grooves with small wavenumbers, the dominant part of the drag is produced by shear, while the pressure form drag and the pressure interaction drag provide minor contributions. For the same grooves with large wavenumbers, the stream lifts up above the grooves due to their blocking effect, resulting in a change in the mechanics of drag formation: the contributions of shear decrease while the contributions of the pressure interaction drag increase, leading to an overall drag increase. In the case of longitudinal grooves, drag is produced by shear, and its rearrangement results in a drag decrease for long-wavelength grooves in spite of an increase of the wetted surface area. An increase of the wavenumber leads to the fluid being squeezed from the troughs and the stream being forced to lift up above the grooves. The shear is nearly eliminated from a large fraction of the wall but the overall drag increases due to reduction of the effective channel opening. It is shown that properly structured grooves are able to eliminate wall shear from the majority of the wetted surface area regardless of the groove orientation, thus exhibiting the potential for the creation of drag-reducing surfaces. Such surfaces can become practicable if a method for elimination of the undesired pressure and shear peaks through proper groove shaping can be found.
Schooling Transitions Within the Lifespan of People With an Intellectual Disability: Perceptions and Recommendations of Ageing Mothers
Authors: Strnadová Iva , Evans David
Published: May 2013

In this paper the authors examine the perceptions of mothers about the schooling transitions, including transitions to postschool options, made by their adult child with an intellectual disability (ID). Twenty mothers of an adult child with an ID living in New South Wales, Australia, and the Czech Republic, aged 48 years or older, were recruited to participate in this study. Mothers were interviewed following a semistructured protocol. The audiotaped interviews were transcribed verbatim, and analysed using a constant comparison analytic approach.

The experiences and issues faced by mothers at differing transitions of their adult child with an ID will be discussed, including issues of school selection, lifelong planning, and engaging with professionals. Common and unique themes within and between each country will be drawn, along with a comparison of findings from recent research reporting on transition experiences of mothers with young children with ID. The concluding discussion will focus on lessons learned about lifelong transition experiences, and pose future directions for enhancing the quality of transitions for persons with special needs and their families.
DRY MATTER ACCUMULATION AND PARTITIONING IN VARIOUS FRACTIONS OF COTTON BOLLS
Authors: TANG FEIYU , XIAO WENJUN
Published: May 2013

The distribution of dry matter among the fractions of cotton boll (the bur, the fibre and the seed) may have significant impact on fibre biomass per boll, and consequently on lint yield. Little is known on how cotton boll allocates available photosynthetic assimilates to its components. A two-year field study was conducted to ascertain the difference in boll dry matter production and partitioning among three cotton genotypes differing in boll size and lint percentage. The dynamics of dry matter production in all fractions of cotton boll against boll age followed a logistic pattern. The final dry weights of all components were largely due to the duration of dry matter exponential accumulation, and less correlated with the maximal rate of exponential accumulation. Partitioning biomass to the bur differed significantly among these genotypes at 10 days post-anthesis (DPA). The genotypic difference in partitioning biomass to the fibre was originally observed at 24 DPA in 2009, while in 2010, this was observed at 17 DPA. The genotypic difference emerged rather late for the seed ratio compared with the fibre ratio and the bur ratio, which was first observed at 45 DPA in 2009 and at 31 DPA in 2010. These results indicate that management practices may need to be applied to cotton plants prior to 31 DPA to ensure optimal boll size and partitioning. Large boll genotype MM-2 consistently maintained higher seed ratio and lower fibre ratio than two other genotypes (2870 and AX) due to more developing ovules in its boll. These differences contributed to significant difference in lint percentage and less difference in fibre mass per boll between MM-2 and 2870 and AX.
THE GOVERNMENT OF FANTE IN THE SEVENTEENTH CENTURY
Authors: LAW ROBIN
Published: May 2013

This article reconsiders the political organization of Fante, a leading state of the Gold Coast, during the seventeenth century, mainly on the basis of contemporary European records. It questions the conventional depiction of Fante as lacking any effective central authority, showing that the Brafo (head of state) in fact exercised significant power. However, there were recurrent conflicts, both between the Brafo and other chiefs in the capital, and between the capital and the provinces. These tensions are situated within the context of growing European trade in gold and slaves, and endemic local warfare, which generated new resources that upset the existing balance of power.
Constructing the (m)other: A-prefixing, stance, and the lessons of motherhood
Authors: Burkette Allison
Published: May 2013

The present study examines two unprompted versions of the same story, related by a mother and daughter in separate sociolinguistic interviews. Following a quantitative intraspeaker comparison of their use of grammatical features associated with Appalachian English within the entirety of their interviews, this study undertakes a close reading of the narratives (along with additional passages from the daughter) to demonstrate the manner in which the two women construct their identities as “mother” and as “other” through conversational narrative and the use of local dialect features. Specifically, this article addresses the use of regional grammatical variables to enact speaker stances toward mothering, focusing on two women's independent recollections of a single incident and how these narratives dialogically construct the (m)other. (Language variation, Appalachian English, stancetaking, motherhood)*
Quantum structure and human thought
Authors: Aerts Diederik , Broekaert Jan , Gabora Liane , Sozzo Sandro
Published: May 2013

We support the authors' claims, except that we point out that also quantum structure different from quantum probability abundantly plays a role in human cognition. We put forward several elements to illustrate our point, mentioning entanglement, contextuality, interference, and emergence as effects, and states, observables, complex numbers, and Fock space as specific mathematical structures.
Can quantum probability help analyze the behavior of functional brain networks?
Authors: Banerjee Arpan , Horwitz Barry
Published: May 2013

Pothos & Busemeyer (P&B) argue how key concepts of quantum probability, for example, order/context, interference, superposition, and entanglement, can be used in cognitive modeling. Here, we suggest that these concepts can be extended to analyze neurophysiological measurements of cognitive tasks in humans, especially in functional neuroimaging investigations of large-scale brain networks.
Quantum probability and comparative cognition
Authors: Grace Randolph C. , Kemp Simon
Published: May 2013

Evolution would favor organisms that can make recurrent decisions in accordance with classical probability (CP) theory, because such choices would be optimal in the long run. This is illustrated by the base-rate fallacy and probability matching, where nonhumans choose optimally but humans do not. Quantum probability (QP) theory may be able to account for these species differences in terms of orthogonal versus nonorthogonal representations.
The cognitive economy: The probabilistic turn in psychology and human cognition
Authors: Kusev Petko , van Schaik Paul
Published: May 2013

According to the foundations of economic theory, agents have stable and coherent “global” preferences that guide their choices among alternatives. However, people are constrained by information-processing and memory limitations and hence have a propensity to avoid cognitive load. We propose that this in turn will encourage them to respond to “local” preferences and goals influenced by context and memory representations.
Quantum models of cognition as Orwellian newspeak
Authors: Lee Michael D. , Vanpaemel Wolf
Published: May 2013

Faced with probabilistic relationships between causes and effects, quantum theory assumes that deterministic causes do not exist, and that only incomplete probabilistic expressions of knowledge are possible. As in its application to physics, this fundamental epistemological stance severely limits the ability of quantum theory to provide insight and understanding in human cognition.
Processes models, environmental analyses, and cognitive architectures: Quo vadis quantum probability theory?
Authors: Marewski Julian N. , Hoffrage Ulrich
Published: May 2013

A lot of research in cognition and decision making suffers from a lack of formalism. The quantum probability program could help to improve this situation, but we wonder whether it would provide even more added value if its presumed focus on outcome models were complemented by process models that are, ideally, informed by ecological analyses and integrated into cognitive architectures.
Realistic neurons can compute the operations needed by quantum probability theory and other vector symbolic architectures
Authors: Stewart Terrence C. , Eliasmith Chris
Published: May 2013

Quantum probability (QP) theory can be seen as a type of vector symbolic architecture (VSA): mental states are vectors storing structured information and manipulated using algebraic operations. Furthermore, the operations needed by QP match those in other VSAs. This allows existing biologically realistic neural models to be adapted to provide a mechanistic explanation of the cognitive phenomena described in the target article by Pothos & Busemeyer (P&B).
Why quantum probability does not explain the conjunction fallacy
Authors: Tentori Katya , Crupi Vincenzo
Published: May 2013

We agree with Pothos & Busemeyer (P&B) that formal tools can be fruitfully employed to model human judgment under uncertainty, including well-known departures from principles of classical probability. However, existing findings either contradict P&B's quantum probability approach or support it to a limited extent. The conjunction fallacy serves as a key illustration of both kinds of problems.
Physics envy: Trying to fit a square peg into a round hole
Authors: Shanteau James , Weiss David J.
Published: May 2013

Pothos & Busemeyer (P&B) argue that classical probability (CP) fails to describe human decision processes accurately and should be supplanted by quantum probability. We accept the premise, but reject P&B's conclusion. CP is a prescriptive framework that has inspired a great deal of valuable research. Also, because CP is used across the sciences, it is a cornerstone of interdisciplinary collaboration.
The Inadequate Life: Rural Industrial Pollution and Lay Epidemiology in China
Authors: Lora-Wainwright Anna
Published: May 2013

Based on fieldwork in a heavily industrialized Yunnan village, this article examines how villagers understand and respond to pollution-related health risks. Building on Robert Weller's (2006) concept of environmental consciousness, it shows that Baocun villagers have developed an acute environmental health consciousness. However, despite earlier instances of collective activism, they no longer act as a community to oppose the harm to their bodies caused by pollution. The article investigates the role of uncertainty surrounding illness causation in deterring action. It argues that uncertainty about pollution's effects on health is reinforced by the social, political and economic contexts and developments in the past few decades. As a result, villagers engage in a form of “lay epidemiology” to make sense of the effects of pollution on their health, but not in a “popular epidemiology” consisting of collective action against presumed health damages. The article concludes with some thoughts on how locals act within and despite uncertainty.
Industrial Pollution and Environmental Health in Rural China: Risk, Uncertainty and Individualization
Authors: Tilt Bryan
Published: May 2013

After more than three decades of extremely rapid industrial growth, China faces an environmental public health crisis. In this article, I examine pollution in the rural industrial sector and its implications for community health. Drawing on recent ethnographic research in an industrial township in rural Sichuan, including interviews with government officials, environmental regulators, industrial workers and local residents, I explore how community members understand the linkages between air and water pollution from nearby factories and their health and well-being. The article has two main goals. The first is to examine the various ways in which uncertainty about pollution sources, about the severity of pollution levels and about the links between pollution and human health shapes villagers' experiences of pollution on a day-to-day basis. The second goal is to examine the rising trend of “individualization” taking place in China today and explore how this process is related to people's experiences of toxic exposure. I consider the implications of this trend for how social scientists should approach the study of environmental illness in contemporary China.
Maximal Empty Boxes Amidst Random Points
Authors: DUMITRESCU ADRIAN , JIANG MINGHUI
Published: May 2013

We show that the expected number of maximal empty axis-parallel boxes amidst n random points in the unit hypercube [0,1]d in $\mathbb{R}^d$ is (1 ± o(1)) $\frac{(2d-2)!}{(d-1)!}$n lnd−1n, if d is fixed. This estimate is relevant to analysis of the performance of exact algorithms for computing the largest empty axis-parallel box amidst n given points in an axis-parallel box R, especially the algorithms that proceed by examining all maximal empty boxes. Our method for bounding the expected number of maximal empty boxes also shows that the expected number of maximal empty orthants determined by n random points in $\mathbb{R}^d$ is (1 ± o(1)) lnd−1n, if d is fixed. This estimate is related to the expected number of maximal (or minimal) points amidst random points, and has application to algorithms for coloured orthogonal range counting.
Biodiversity-based development in Small Island Developing States
Authors: Teelucksingh Sonja , Nunes Paulo A.L.D. , Perrings Charles
Published: May 2013

Small Island Developing States (SIDS) are quite diverse in terms of various development metrics, but are uniformly vulnerable both to macroeconomic shocks and to changes in the biodiversity that supports fisheries and tourism. This special section assembles a set of papers that analyze international demand for the natural resources associated with the two sectors, and the factors that lie behind changes in their supply. Since each stresses the resource base, albeit in different ways, we argue that limits on tourist pressure will be as important as limits on allowable fish catches in the future. We identify the challenge for SIDS as the need to implement an integrated, sustainable resource management strategy that allows biological resources to be allocated to their highest valued uses, while respecting the interests of those with prior rights to those resources.
Antidepressant-induced differential ubiquitination of β-arrestins 1 and 2 in mononuclear leucocytes of patients with depression
Authors: Golan Moran , Schreiber Gabriel , Avissar Sofia
Published: May 2013

β-Arrestins 1 and 2, cytosolic proteins known to mediate receptor desensitization, endocytosis and G protein-independent signalling, are post-translationally modified by ubiquitination regulating their ability to serve as adaptors and scaffolds. β-Arrestins were suggested to play a role in the pathophysiology of depression and in antidepressant mechanism of action. To determine whether a depressive episode or antidepressant treatment induce significant selective differences in β-arrestin 1 and 2 levels or their ubiquitination patterns in leucocytes of patients with depression, 46 outpatients diagnosed with a depressive episode were examined before and after 4-wk antidepressant treatment compared with age- and gender-matched control subjects. β-Arrestin levels were measured by immunoblotting using anti-arrestin antibodies. Ubiquitination of β-arrestins was measured using anti-ubiquitin antibodies followed by an immunoprecipitation step and immunoblotting using anti-arrestin antibodies. Antidepressants induced selective alterations in leucocyte β-arrestin 1 and 2 levels and ubiquitination. The levels of β-arrestin 1 and 2 and their ubiquitinated forms in leucocytes of yet untreated patients with depression were significantly decreased in a symptom severity correlated manner compared to control subjects. Antidepressants normalized β-arrestin 1 and 2 levels and uncovered novel differences between the two isoforms: (a) while antidepressants normalized ubiquitination of β-arrestin 1, ubiquination of β-arrestin 2 was unaffected; (b) while under antidepressants ubiquitination extent of β-arrestin 1 positively correlated with its level, an inverse picture of negative correlation was found between ubiquitination extent of β-arrestin 2 and its level. We conclude that antidepressants may serve as a tool to detect functional differences between the two β-arrestin isoforms and that through these differential effects antidepressants can induce specific alterations in alternative cellular signalling.
MULTIPLE GROUP THREAT AND MALLEABLE WHITE ATTITUDES TOWARDS ACADEMIC MERIT
Authors: Samson Frank L.
Published: May 2013

As the White populace in the United States moves toward numerical minority status by 2042, how might Whites respond to impending threat of losing their dominant group position? In particular, how will Whites react at selective, elite universities, where Asians are increasingly prominent and other non-Whites are maintaining or capturing a larger share of enrollments? Drawing on group position theory, I test White commitment to meritocracy as a public policy, using a survey-based experiment (599 California adult residents) to examine the importance grade point average should have in public university admissions. Whites decrease the importance that grade point average should have when Asian group threat is primed. However, White Californians increase the importance that grade point average should have when thinking about group threat from either Blacks or Blacks and Asians simultaneously. Ethnoracial outgroup threat shifts White support for meritocracy in different directions.
Attributions of Competence Mediate the Behaviors of Caregivers and Older Adults
Authors: Bustillos Antonio , Fernández Ballesteros Rocío
Published: May 2013

This study tests whether age stereotypes held by professional caregivers and health professionals have an effect on the behaviors of these professionals and the competence of older adults. A repeated-measures design was implemented in the State of Colima (Mexico). The first phase recorded aging stereotypes; the second phase observed the functioning of caregivers and older adults. Analyses revealed that stereotypical beliefs about competence mediated the relationships between the behaviors of caregivers and the older adults. Given that aging stereotypes held by caregivers negatively affect the competence behaviors of older persons, if we want to promote competence and active aging in senior citizens it would seem important to promote change in the stereotypical beliefs of their caregivers.
Calfacilitin is a calcium channel modulator essential for initiation of neural plate development
Authors: Papanayotou Costis , De Almeida Irene , Liao Ping , Oliveira Nidia M. M. , Lu Song-Qing , Kougioumtzidou Eleni , Zhu Lei , Shaw Alex , Sheng Guojun , Streit Andrea , Yu Dejie , Wah Soong Tuck , Stern Claudio D.
Published: May 2013

Calcium fluxes have been implicated in the specification of the vertebrate embryonic nervous system for some time, but how these fluxes are regulated and how they relate to the rest of the neural induction cascade is unknown. Here we describe Calfacilitin, a transmembrane calcium channel facilitator that increases calcium flux by generating a larger window current and slowing inactivation of the L-type CaV1.2 channel. Calfacilitin binds to this channel and is co-expressed with it in the embryo. Regulation of intracellular calcium by Calfacilitin is required for expression of the neural plate specifiers Geminin and Sox2 and for neural plate formation. Loss-of-function of Calfacilitin can be rescued by ionomycin, which increases intracellular calcium. Our results elucidate the role of calcium fluxes in early neural development and uncover a new factor in the modulation of calcium signalling.
Schritt für Schritt – Intraossäre Punktion
Authors: Bornemann Philipp , Reu Hans-Peter
Published: May 2013

Lässt sich ein peripher venöser Zugang nicht legen,herrschen erschwerte Bedingungen oder besteht die Gefahr einesZeitverlusts, stellt die intraossäre Punktion eine gute Alternativedar. Sie ist eine Notfallmaßnahme, die mit etwas Übung und bei derrichtigen Indikation rasch und problemlos einen sicheren Zugangzum Gefäßsystem des Patienten schaff t.
Dynamics and rheology of concentrated, finite-Reynolds-number suspensions in a homogeneous shear flow
Authors: Yeo Kyongmin , Maxey Martin R.
Published: May 2013

We present the lubrication-corrected force-coupling method for the simulation of concentrated suspensions under finite inertia. Suspension dynamics are investigated as a function of the particle-scale Reynolds number \documentclass[12pt]{minimal}\begin{document}$Re_{\dot{\gamma }}$\end{document}Reγ̇ and the bulk volume fraction ϕ in a homogeneous linear shear flow, in which \documentclass[12pt]{minimal}\begin{document}$Re_{\dot{\gamma }}$\end{document}Reγ̇ is defined from the density ρf and dynamic viscosity μ of the fluid, particle radius a, and the shear rate \documentclass[12pt]{minimal}\begin{document}$\dot{\gamma }$\end{document}γ̇ as \documentclass[12pt]{minimal}\begin{document}$Re_{\dot{\gamma }}= \rho _f \dot{\gamma } a^2 / \mu$\end{document}Reγ̇=ρfγ̇a2/μ. It is shown that the velocity fluctuations in the velocity-gradient and vorticity directions decrease at larger \documentclass[12pt]{minimal}\begin{document}$Re_{\dot{\gamma }}$\end{document}Reγ̇. However, the particle self-diffusivity is found to be an increasing function of \documentclass[12pt]{minimal}\begin{document}$Re_{\dot{\gamma }}$\end{document}Reγ̇ as the motion of the suspended particles develops a longer auto-correlation under finite fluid inertia. It is shown that finite-inertia suspension flows are shear-thickening and the particle stresses become highly intermittent as \documentclass[12pt]{minimal}\begin{document}$Re_{\dot{\gamma }}$\end{document}Reγ̇ increases. To study the detailed changes in the suspension microstructure and rheology, we introduce a particle-stress-weighted pair-distribution function. The stress-weighted pair-distribution function clearly shows that the increase of the effective viscosity at high \documentclass[12pt]{minimal}\begin{document}$Re_{\dot{\gamma }}$\end{document}Reγ̇ is mostly related to the strong normal lubrication interaction in the compressive principal axis of the shear flow.
Conformational isomerisms and nano-aggregation in substituted alkylammonium nitrates ionic liquids: An x-ray and computational study of 2-methoxyethylammonium nitrate
Authors: Campetella Marco , Gontrani Lorenzo , Bodo Enrico , Ceccacci Francesca , Marincola Flaminia Cesare , Caminiti Ruggero
Published: May 2013

In this study, we discuss, using molecular dynamics simulations and energy-dispersive x-ray diffraction data, how a conformational isomerism can dramatically alter the nanosegregation phenomena that take place in a prototypical ionic liquid. The diffraction patterns of liquid 2-methoxyethylammonium nitrate are compared with the results from molecular dynamics simulations. The simulations conditions and force field parameters have been varied producing different charge models and different populations of conformers of the cation. We show that, while the short range structure is relatively unchanged in the models, the long range aggregation phenomena deemed responsible for the appearance of low Q peaks in the X-ray patterns strongly depend on the choice of the charge model. In the title compound, the best agreement with the experiment, where no low Q peaks appear, occurs if the point charges are calculated using the gauche conformation of the cation, which is characterized by an intramolecular hydrogen bond between ammonium and ether groups.
On trajectory-based nonadiabatic dynamics: Bohmian dynamics versus trajectory surface hopping
Authors: Curchod Basile F. E. , Tavernelli Ivano
Published: May 2013

In this work, we present a complete derivation of the NonAdiabatic Bohmian DYnamics (NABDY) equations of motion. This approach naturally emerges from a transformation of the molecular time-dependent Schrödinger equation in the adiabatic representation of the electronic states. The numerical implementation of the method is discussed while simple nonadiabatic models are employed to address the accuracy of NABDY and to reveal its ability to capture nuclear quantum effects that are missed in trajectory surface hopping (TSH) due to the independent trajectory approximation. A careful comparison of the correlated, NABDY, and the uncorrelated, TSH, propagation is also given together with a description of the main approximations and assumptions underlying the “derivation” of a nonadiabatic molecular dynamics scheme based on classical trajectories.
Polarization rotation theory for field-induced-phase transitions in BaTiO3 single crystal
Authors: Zhang Hui
Published: May 2013

We have proposed the polarization rotation theory to understand the underlying physics of the large piezoelectric effect in ferroelectric crystals by referring to the coherent rotation model in ferromagnetism. When both the electric field energy and crystalline anisotropy energy are taken into account, the polarization in BaTiO3 crystal can be rotated toward the field direction. The numerical results are in agreement with the experimental observations and have indicated the highly anisotropic polarization rotations and the field-induced-phases with different symmetries in the crystal. This theory is helpful for understanding the polarization reversal and the electromechanical effect in ferroelectric materials.
Anisotropy induced crossover from weakly to strongly first order melting of two dimensional solids
Authors: Singh Rakesh S. , Santra Mantu , Bagchi Biman
Published: May 2013

Melting and freezing transitions in two dimensional (2D) systems are known to show highly unusual characteristics. Most of the earlier studies considered atomic systems: the melting of 2D molecular solids is still largely unexplored. In order to understand the role of anisotropy as well as multiple energy and length scales present in molecular systems, here we report computer simulation studies of melting of 2D molecular systems. We computed a limited portion of the solid-liquid phase diagram. We find that the interplay between the strength of isotropic and anisotropic interactions can give rise to rich phase diagram consisting of isotropic liquid and two crystalline phases—honeycomb and oblique. The nature of the transition depends on the relative strength of the anisotropic interaction and a strongly first order melting turns into a weakly first order transition on increasing the strength of the isotropic interaction. This crossover can be attributed to an increase in stiffness of the solid phase free energy minimum on increasing the strength of the anisotropic interaction. The defects involved in melting of molecular systems are quite different from those known for the atomic systems.
Characterization system for research on energy storage capacitors
Authors: Noriega J. R. , Iyore O. D. , Budime C. , Gnade B. , Vasselli J.
Published: May 2013

In this work a characterization system for high energy-density capacitors is described and demonstrated. Capacitors are being designed using thin-film technology in an attempt to achieve higher energy-density levels by operating the devices at a high voltage. These devices are fabricated from layers of 100 nm aluminum and a layer of polyvinylidene fluoride-hexafluoropropylene on a polyethylene naphthalate plastic substrate. The devices have been designed to store electrical charge at up to 200 V. Characterizations of these devices focus on the measurement of capacitance vs bias voltage and temperature, equivalent series resistance, and charge/discharge cycles. For the purpose of the characterization of these capacitors, an electronic charge/discharge interface was designed and tested.
Vibronic effects on the low-lying electronic excitations in CO2 induced by electron impact
Authors: Watanabe Noboru , Hirayama Tsukasa , Suzuki Daisuke , Takahashi Masahiko
Published: May 2013

We report an angle-resolved electron energy loss spectroscopy (EELS) study on the valence-shell electronic excitations of CO2. Experimentally, momentum-transfer-dependent generalized oscillator strengths (GOSs) or GOS profiles for low-lying electronic excitations have been derived from EELS spectra measured at incident electron energy of 3 keV. Theoretically, we have calculated GOS profiles using wave functions at the equation-of-motion coupled-cluster singles and doubles level. In the calculation, vibronic effects are taken into account by evaluating the electronic transition amplitudes along the individual normal coordinates. The calculation satisfactorily reproduces the experiment for the 1Πg and 1Δu transitions and reveals prominent roles of strong coupling between the associated mixed-Rydberg-valence and valence excited states through the bending vibration of CO2. Vibronic effects on GOS profiles have also been examined for the 1Σu+, 1Πu, and 21Πg transitions.
A steady-state high-temperature method for measuring thermal conductivity of refractory materials
Authors: Manzolaro M. , Corradetti S. , Andrighetto A. , Ferrari L.
Published: May 2013

A new methodology and an instrumental setup for the thermal conductivity estimation of isotropic bulk graphite and different carbides at high temperatures are presented. The method proposed in this work is based on the direct measurement of temperature and emissivity on the top surface of a sample disc of known dimensions. Temperatures measured under steady-state thermal equilibrium are then used to estimate the thermal conductivity of the sample by making use of the inverse parameter estimation technique. Thermal conductivity values obtained in this way are then compared to the material data sheets and values found in literature. The reported work has been developed within the Research and Development framework of the SPES (Selective Production of Exotic Species) project at INFN-LNL (Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali di Legnaro).
Variation of droplet acidity during evaporation
Authors: Malevanets Anatoly , Consta Styliani
Published: May 2013

Variation of acidity and associated chemical changes of macromolecules in evaporating droplets is of central importance in electrosprayed aerosols. We study changes in acidity during evolution of a droplet that is composed of solvent and a charge binding macromolecule. We analyze the acidity of the droplet using analytical theory and stochastic modeling. We derive a universal relation for the minimum pH of a droplet in the presence of a protein and the results are confirmed by the stochastic modeling of ubiquitin and lysozyme at varying values of pH. We establish that in acidic droplets, once the number of solvated charges reaches the macroion charge, the further droplet evaporation, counter-intuitively, reduces the number of charges on the macromolecule and increases the droplet pH.
Modeling of current characteristics of segmented Langmuir probe on DEMETER
Authors: Imtiaz Nadia , Marchand Richard , Lebreton Jean-Pierre
Published: May 2013

We model the current characteristics of the DEMETER Segmented Langmuir probe (SLP). The probe is used to measure electron density and temperature in the ionosphere at an altitude of approximately 700 km. It is also used to measure the plasma flow velocity in the satellite frame of reference. The probe is partitioned into seven collectors: six electrically insulated spherical segments and a guard electrode (the rest of the sphere and the small post). Comparisons are made between the predictions of the model and DEMETER measurements for actual ionospheric plasma conditions encountered along the satellite orbit. Segment characteristics are computed numerically with PTetra, a three-dimensional particle in cell simulation code. In PTetra, space is discretized with an unstructured tetrahedral mesh, thus, enabling a good representation of the probe geometry. The model also accounts for several physical effects of importance in the interaction of spacecraft with the space environment. These include satellite charging, photoelectron, and secondary electron emissions. The model is electrostatic, but it accounts for the presence of a uniform background magnetic field. PTetra simulation results show different characteristics for the different probe segments. The current collected by each segment depends on its orientation with respect to the ram direction, the plasma composition, the magnitude, and the orientation of the magnetic field. It is observed that the presence of light H+ ions leads to a significant increase in the ion current branch of the I-V curves of the negatively polarized SLP. The effect of the magnetic field is demonstrated by varying its magnitude and direction with respect to the reference magnetic field. It is found that the magnetic field appreciably affects the electron current branch of the I-V curves of certain segments on the SLP, whereas the ion current branch remains almost unaffected. PTetra simulations are validated by comparing the computed characteristics and their angular anisotropy with the DEMETER measurements, as simulation results are found to be in good agreement with the measurements.
Relativistic solutions for one- and two-dimensional space-charge limited current in coaxial diode
Authors: Yang Zhanfeng , Liu Guozhi , Shao Hao , Yan Teng , Zhang Yuchuan
Published: May 2013

This paper reports the two-dimensional physics and space-charge limited current (SLC) of coaxial diodes with a finite-length emitter. A full-voltage and one-dimensional approximate solution is first obtained by matching the non-relativistic solution to the super-relativistic solution. Including the effects of fields induced by the anode current and the beam itself yields the pinch-limited current in the coaxial diode. The SLC of a practically applied coaxial diode with a finite length emitter is obtained by a semi-analytical method. The solutions well agree with numerical solutions and particle-in-cell simulations.
Anisotropy of the silicon valence band induced by strain with various orientations
Authors: Inaoka Takeshi , Kinjyo Yūki , Yanagisawa Susumu , Tomori Kazuya
Published: May 2013

Using the first-principles-optimized k•p method and the first-principles density-functional theory in a cooperative manner, we investigate the anisotropy of the silicon valence band induced by uniaxial or biaxial strain with various orientations. Our analysis of the angle dependence of the hole effective mass m* shows that, for all the strain orientations considered, the m* value becomes strikingly small in the strain-parallel direction for uniaxial compression and in the strain-perpendicular direction for biaxial tensility. Our examination also clarifies the equivalence between the effect of uniaxial compression (tensility) and that of biaxial tensility (compression) in the plane perpendicular to the above uniaxial compression (tensility). This equivalence can be elucidated in terms of the ratio of the lattice constant along the uniaxial-strain direction to that in the biaxial-strain plane. We also recognize that the normal compression involved in biaxial tensility under the condition of no normal stress increases the valence-band splitting, and consequently extends the segment of the highest valence-band dispersion with a conspicuously reduced m* value to a lower energy region, so that this segment can accommodate most of the holes.
A maximum entropy thermodynamics of small systems
Authors: Dixit Purushottam D.
Published: May 2013

We present a maximum entropy approach to analyze the state space of a small system in contact with a large bath, e.g., a solvated macromolecular system. For the solute, the fluctuations around the mean values of observables are not negligible and the probability distribution P(r) of the state space depends on the intricate details of the interaction of the solute with the solvent. Here, we employ a superstatistical approach: P(r) is expressed as a marginal distribution summed over the variation in β, the inverse temperature of the solute. The joint distribution P(β, r) is estimated by maximizing its entropy. We also calculate the first order system-size corrections to the canonical ensemble description of the state space. We test the development on a simple harmonic oscillator interacting with two baths with very different chemical identities, viz., (a) Lennard-Jones particles and (b) water molecules. In both cases, our method captures the state space of the oscillator sufficiently well. Future directions and connections with traditional statistical mechanics are discussed.