bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three dimensional simulations of Hall magnetohydrodynamics
Authors: Gómez Daniel O. 
Published: June 2011

AbstractTurbulent flows take place in a large variety of astrophysical objects, and often times are the source of dynamo generated magnetic fields. Much of the progress in our understanding of dynamo mechanisms, has been made within the theoretical framework of magnetohydrodynamics (MHD). However, for sufficiently diffuse media, the Hall effect eventually becomes non-negligible.We present results from simulations of the Hall-MHD equations. The simulations are performed with a pseudospectral code to achieve exponentially fast convergence. We study the role of the Hall effect in the dynamo efficiency for different values of the Hall parameter.
Shock refraction from classical gas to relativistic plasma environments
Authors: Keppens Rony , Delmont Peter , Meliani Zakaria 
Published: June 2011

AbstractThe interaction of (strong) shock waves with localized density changes is of particular relevance to laboratory as well as astrophysical research. Shock tubes have been intensively studied in the lab for decades and much has been learned about shocks impinging on sudden density contrasts. In astrophysics, modern observations vividly demonstrate how (even relativistic) winds or jets show complex refraction patterns as they encounter denser interstellar material.In this contribution, we highlight recent insights into shock refraction patterns, starting from classical up to relativistic hydro and extended to magnetohydrodynamic scenarios. Combining analytical predictions for shock refraction patterns exploiting Riemann solver methodologies, we confront numerical, analytical and (historic) laboratory insights. Using parallel, grid-adaptive simulations, we demonstrate the fate of Richtmyer-Meshkov instabilities when going from gaseous to magnetized plasma scenarios. The simulations invoke idealized configurations closely resembling lab analogues, while extending them to relativistic flow regimes.
Formation of electron clouds during particle acceleration in a 3D current sheet
Authors: Zharkova Valentina V. , Siversky Taras 
Published: June 2011

AbstractAcceleration of protons and electrons in a reconnecting current sheet (RCS) is investigated with the test particle and particle-in-cell (PIC) approaches in the 3D magnetic configuration including the guiding field. PIC simulations confirm a spatial separation of electrons and protons towards the midplane and reveal that this separation occur as long as protons are getting accelerated. During this time electrons are ejected into their semispace of the current sheet moving away from the midplane to distances up to a factor of 103 – 104 of the RCS thickness and returning back to the RCS. This process of electron circulation around the current sheet midplane creates a cloud of high energy electrons around the current sheet which exists as long as protons are accelerated. Only after protons gain sufficient energy to break from the magnetic field of the RCS, they are ejected to the opposite semispace dragging accelerated electrons with them. These clouds can be the reason of hard X-ray emission in coronal sources observed by RHESSI.
Magnetic helicity fluxes in αΩ dynamos
Authors: Candelaresi Simon , Brandenburg Axel 
Published: June 2011

AbstractIn turbulent dynamos the production of large-scale magnetic fields is accompanied by a separation of magnetic helicity in scale. The large- and small-scale parts increase in magnitude. The small-scale part can eventually work against the dynamo and quench it, especially at high magnetic Reynolds numbers. A one-dimensional mean-field model of a dynamo is presented where diffusive magnetic helicity fluxes within the domain are important. It turns out that this effect helps to alleviate the quenching. Here we show that internal magnetic helicity fluxes, even within one hemisphere, can be important for alleviating catastrophic quenching.
Current-Driven Kink Instability in Relativistic Jets
Authors: Mizuno Yosuke , Hardee Philip E. , Lyubarsky Yuri , Nishikawa Ken-Ici 
Published: June 2011

AbstractWe have investigated the development of current-driven (CD) kink instability in relativistic jets via 3D RMHD simulations. In this investigation a static force-free equilibrium helical magnetic field configuration is considered in order to study the influence of the initial configuration on the linear and nonlinear evolution of the instability. We found that the initial configuration is strongly distorted but not disrupted by the CD kink instability. The linear growth and nonlinear evolution of the CD kink instability depends moderately on the radial density profile and strongly on the magnetic pitch profile. Kink amplitude growth in the nonlinear regime for decreasing magnetic pitch leads to a slender helically twisted column wrapped by magnetic field. On the other hand, kink amplitude growth in the nonlinear regime nearly ceases for increasing magnetic pitch.
iTherapy: The Revolution of Mobile Devices Within the Field of Speech Therapy
Authors: Fernandes Barbara 
Published: June 2011

The iPhone®, iPod touch® and the iPad® are becoming widely used as therapy tools. This article will introduce the devices' basic features that can be used by speech-language pathologists (SLPs) to support service delivery in schools, report the results of a survey addressing current use and implementation of the devices in the school setting, introduce basic concepts behind applications for speech and language therapy, and guide SLPs when choosing accessories for the devices that will be used for therapy. The iDevices have made the use of technology within the field of speech pathology affordable, convenient, and user-friendly, key features for the adoption of any new tool.
(Note: iPhone®, iPod touch® and iPad® are registered trademarks of Apple Inc.)
Atlantic Salmon at Risk: Apparent Rapid Declines in Effective Population Size in Southern European Populations
Authors: Horreo J. L. , Machado‐Schiaffino G. , Griffiths A. M. , Bright D. , Stevens J. R. , Garcia‐Vazquez E. 
Published: June 2011

AbstractPopulations of southern European Atlantic salmon Salmo salar are subjected to exploitation by sportfishing and exhibit evidence of dramatic catch reduction for the same fishing effort over recent history. We employed nine microsatellite loci as markers to estimate effective population sizes of Atlantic salmon in five rivers of northern Spain for comparison with 1990s data describing the same populations; marked declines in effective population sizes over the last decade were detected, and a reduced census size is proposed to be one of the probable causes. These estimates highlight the endangered status of the Atlantic salmon populations in northern Spain. A reduction in fishing effort and an increase in protective measures are recommended for the conservation of these fragile populations at the southernmost edge of the species’ natural distribution.
Physical processes in EUV sources for microlithography
Authors: Banine V Y , Koshelev K N , Swinkels G H P M 
Published: June 2011

The source is an integral part of an extreme ultraviolet lithography (EUVL) tool. Such a source, as well as the EUVL tool, has to fulfil very high demands both technical and cost oriented. The EUVL tool operates at a wavelength of 13.5 nm, which requires the following new developments.The light production mechanism changes from conventional lamps and lasers to relatively high-temperature emitting plasmas.The light transport, mainly refractive for deep ultraviolet (DUV), should be reflective for EUV.The source specifications as derived from the customer requirements on wafer throughput mean that the output EUV source power has to be hundreds of watts. This in its turn means that tens to hundreds of kilowatts of dissipated power has to be managed in a relatively small volume.In order to keep lithography costs as low as possible, the lifetime of the components should be as long as possible and at least of the order of thousands of hours. This poses a challenge for the sources, namely how to design and manufacture components robust enough to withstand the intense environment of high heat dissipation, flows of several keV ions as well as the atomic and particular debris within the source vessel.As with all lithography tools, the imaging requirements demand a narrow illumination bandwidth. Absorption of materials at EUV wavelengths is extreme with extinguishing lengths of the order of tens of nanometres, so the balance between high transmission and spectral purity requires careful engineering.All together, EUV lithography sources present technological challenges in various fields of physics such as plasma, optics and material science.These challenges are being tackled by the source manufacturers and investigated extensively in the research facilities around the world.An overview of the published results on the topic as well as the analyses of the physical processes behind the proposed solutions will be presented in this paper.
Biphasic Activation of Extracellular Signal-regulated Kinase in Anterior Cingulate Cortex Distinctly Regulates the Development of Pain-related Anxiety and Mechanical Hypersensitivity in Rats after Incision
Authors: Dai Ru-Ping , Li Chang-Qi , Zhang Jian-Wei , Li Fang , Shi Xu-Dan , Zhang Jian-Yi , Zhou Xin-Fu 
Published: June 2011

Background
A recent study has demonstrated that surgical incision induces an anxiety-like behavior but its relationship with incision-evoked mechanical hypersensitivity remains elusive. Extracellular signal-regulated kinase (ERK) activity in the anterior cingulate cortex (ACC) is important for the affective pain. The current study aims to explore ERK1/2 activity in the ACC and its role in the development of anxiety and mechanical hypersensitivity after incision.

Methods
Anxiety-like behavior was measured by elevated plus maze experiment and open field test after hind paw incision. ERK1/2 phosphorylation was determined by immunohistochemistry and Western blot. Cannulae were implanted into the bilateral ACC for the intra-ACC injection of ERK inhibitors PD98059 and U0126. Brushing (innocuous stimulus) was used to investigate its effect on ERK activation under the incision-evoked painful condition.

Results
The anxiety-like behavior induced by the hind paw incision persisted longer than mechanical hypersensitivity. One hind paw incision resulted in a biphasic ERK activation in bilateral ACC. Inhibiting ERK activation in the early phase attenuated pain-related anxiety and mechanical hypersensitivity whereas inhibiting ERK activation in the late phase only reduced the anxiety-like behavior. During the time interval between two phases of ERK activation, brushing the incised skin dramatically increased ERK phosphorylation in the ACC.

Conclusions
These data suggest that in the early phase of postoperative pain, pain-related anxiety and mechanical hypersensitivity are tightly linked and regulated by the ERK activation in the ACC. However, in the late phase of postoperative pain, ERK activation in the ACC is only required for the expression of pain-related anxiety but not mechanical hypersensitivity.
WEREWOLF, a Regulator of Root Hair Pattern Formation, Controls Flowering Time through the Regulation ofFTmRNA Stability
Authors: Seo Eunjoo , Yu Jihyeon , Ryu Kook Hui , Lee Myeong Min , Lee Ilha 
Published: June 2011

AbstractA key floral activator, FT, integrates stimuli from long-day, vernalization, and autonomous pathways and triggers flowering by directly regulating floral meristem identity genes in Arabidopsis (Arabidopsis thaliana). Since a small amount of FT transcript is sufficient for flowering, the FT level is strictly regulated by diverse genes. In this study, we show that WEREWOLF (WER), a MYB transcription factor regulating root hair pattern, is another regulator of FT. The mutant wer flowers late in long days but normal in short days and shows a weak sensitivity to vernalization, which indicates that WER controls flowering time through the photoperiod pathway. The expression and double mutant analyses showed that WER modulates FT transcript level independent of CONSTANS and FLOWERING LOCUS C. The histological analysis of WER shows that it is expressed in the epidermis of leaves, where FT is not expressed. Consistently, WER regulates not the transcription but the stability of FT mRNA. Our results reveal a novel regulatory mechanism of FT that is non cell autonomous.
Immune adaptive microenvironment profiles in intracerebral and intrasplenic lymphomas share common characteristics
Authors: Donnou S , Galand C , Daussy C , Crozet L , Fridman W H , Sautès-Fridman C , Fisson S 
Published: June 2011

Summary
A large body of evidence indicates that the immune microenvironment controls tumour development. Primary central nervous system lymphomas (PCNSL) are aggressive tumours growing in the central nervous system (CNS). To evaluate the role and characteristics of this immune-privileged site in anti-tumour defences, we compared the cellular and molecular immune microenvironments of growing murine lymphoma B cells injected into the brain or the spleen. In the brain, immune cells, including dendritic cells and T lymphocytes with a large proportion of CD4+forkhead box P3 (FoxP3+) regulatory T cells, rapidly infiltrated the tumour microenvironment. These populations also increased in number in the spleen. The T cell cytokine profiles in tumour-bearing mice were similar in the two sites, with predominant T helper type 1 (Th1)/Th17 polarization after polyclonal stimulation, although some interleukin (IL)-4 could also be found. We demonstrated that these T cells have anti-tumour activity in the CNS, although less than in the spleen: nude mice that received lymphoma cells intracerebrally died significantly earlier than immunocompetent animals. These results demonstrate that the brain is able to recruit all the major actors to mount a specific anti-tumour immune response against lymphoma.
5‐Oxoprolinase deficiency: report of the first human OPLAH mutation
Authors: Almaghlouth IA , Mohamed JY , Al‐Amoudi M , Al‐Ahaidib L , Al‐Odaib A , Alkuraya FS 
Published: June 2011

Almaghlouth IA, Mohamed JY, Al‐Amoudi M, Al‐Ahaidib L, Al‐Odaib A, Alkuraya FS. 5‐Oxoprolinase deficiency: report of the first human OPLAH mutation.Gamma‐glutamyl cycle is a six‐enzyme cycle that represents the primary pathway for glutathione synthesis and degradation. 5‐Oxoprolinase deficiency is an extremely rare disorder of the gamma‐glutamyl cycle with only eight patients reported to date. Debate continues as to whether this is a benign biochemical defect because of the heterogeneity of the clinical presentation which ranges from normal to significant neurological involvement. Here, we report the first molecularly characterized patients with 5‐oxoprolinase deficiency due to a mutation in OPLAH (which encodes 5‐oxoprolinase). The largely benign clinical course of the patients described herein despite persistent 5‐oxoprolinuria highlights the importance of establishing a molecular diagnosis in the few cases with abnormal neurological outcome to exclude potentially overlapping biochemical defects and to explore potential genotype/phenotype correlation.
Multivariate analyses of salt stress and metabolite sensing in auto‐ and heterotroph Chenopodium cell suspensions
Authors: Wongchai C. , Chaidee A. , Pfeiffer W. 
Published: June 2011

AbstractGlobal warming increases plant salt stress via evaporation after irrigation, but how plant cells sense salt stress remains unknown. Here, we searched for correlation‐based targets of salt stress sensing in Chenopodium rubrum cell suspension cultures. We proposed a linkage between the sensing of salt stress and the sensing of distinct metabolites. Consequently, we analysed various extracellular pH signals in autotroph and heterotroph cell suspensions. Our search included signals after 52 treatments: salt and osmotic stress, ion channel inhibitors (amiloride, quinidine), salt‐sensing modulators (proline), amino acids, carboxylic acids and regulators (salicylic acid, 2,4‐dichlorphenoxyacetic acid). Multivariate analyses revealed hirarchical clusters of signals and five principal components of extracellular proton flux. The principal component correlated with salt stress was an antagonism of γ‐aminobutyric and salicylic acid, confirming involvement of acid‐sensing ion channels (ASICs) in salt stress sensing. Proline, short non‐substituted mono‐carboxylic acids (C2–C6), lactic acid and amiloride characterised the four uncorrelated principal components of proton flux. The proline‐associated principal component included an antagonism of 2,4‐dichlorphenoxyacetic acid and a set of amino acids (hydrophobic, polar, acidic, basic). The five principal components captured 100% of variance of extracellular proton flux. Thus, a bias‐free, functional high‐throughput screening was established to extract new clusters of response elements and potential signalling pathways, and to serve as a core for quantitative meta‐analysis in plant biology. The eigenvectors reorient research, associating proline with development instead of salt stress, and the proof of existence of multiple components of proton flux can help to resolve controversy about the acid growth theory.
Culex molestus Forskal (Diptera: Culicidae) in Australia: colonisation, stenogamy, autogeny, oviposition and larval development
Authors: Kassim Nur Faeza A , Webb Cameron E , Russell Richard C 
Published: June 2011

AbstractThe Culex pipiens subgroup of mosquitoes contains some of the most important vector species internationally. In Australia, there are four species currently present that belong to that subgroup, with Culex molestus one species that is closely associated with urban environments, and concern has been raised as to the potential role this species may play in the transmission of exotic and endemic Flaviviruses. An understanding of the biology and ecology of this species is crucial for the establishment of laboratory colonies and further experimentation. Using field‐collected adult mosquitoes, a laboratory colony of Cx. molestus was established and sustained for 10 generations. The species was strongly stenogamous and, across all generations, over 95% of females laid autogenous egg rafts with a mean egg raft size of 54.2 ± 17.7 eggs. The females did not display a preference for highly organic oviposition water and readily laid eggs in clean water. While colony maintenance could be sustained on autogenous egg rafts alone, the species readily fed on rodents and post‐blood feeding egg rafts were significantly larger than autogenous egg rafts. Larval development was the shortest, 12.9 ± 0.4 days, at a mean temperature of 24.6 ± 0.6°C and the longest was 29.4 ± 0.7 days at 12.1 ± 3.2°C. Adults emerging from larvae raised at 12.1 ± 3.2°C maintained the ability to lay autogenous egg rafts. Results indicate that Cx. molestus can be readily colonised and large numbers of mosquitoes can be reared for biological, ecological and vector competence experiments.
Survival over winter and spring emergence of Lucilia cuprina (Diptera: Calliphoridae) in south‐eastern Australia
Authors: De Cat Sandra , Larsen John W A , Anderson Norman 
Published: June 2011

AbstractOverwintering of larvae of the Australian sheep blowfly, Lucilia cuprina (Wiedemann), was studied over 2 years in south‐eastern Australia. There was a biphasic pattern of emergence of flies from larvae entering the ground during April. Some larvae deposited in April developed immediately and emerged in late autumn, whereas others entered a state of arrested development and resumed development the following spring. Overwintering mortality was generally high, but varied between years and between replicate cohorts deposited at the same time. Overwintering larvae resumed development in early to mid‐September, coinciding with an increase in soil temperatures of 1.5°C over a 4‐day period and soil temperatures remaining above 11°C for at least 7 consecutive days. Spring emergence of the first generation of flies after winter was synchronous from larvae deposited at different times. The first flies were detected on 2 October and 26 September in consecutive years and emergence continued for up to 50 days. Free‐ranging flies were first caught in traps on 17 and 7 October in consecutive years, and numbers showed a large peak in late November and a smaller one in early March. No flies were caught from May to September. More detailed studies on the immature stages of L. cuprina, such as the conditions that induce and terminate arrested development of post‐feeding larvae, and those that determine the survival of larvae and pupae in the soil, are needed. This knowledge could be used to refine control programs based on the treatment of sheep with long‐acting insecticide in September or October (‘early season treatment’), which aims to prevent propagation of fly numbers from the first generation of flies and thus reduce the prevalence of fly‐strike on sheep farms.
Path prediction of I + III mixed mode fatigue crack propagation
Authors: LI H. F. , QIAN C. F. 
Published: June 2011

ABSTRACTIn this paper, compact tension specimens with tilted cracks under monotonic fatigue loading were tested to investigate I + III mixed mode fatigue crack propagation in the material of No. 45 steel with the emphasis on the propagation rate expression and the path prediction. It is found that during the mode transformation process, the crack propagation rate is still controlled by the mode I stress intensity factor; and Paris equation also holds for the relationship between and ΔKI. Crack propagation path can be predicted only when both the crack mode transformation rate and propagation rate are available.
The role of the cerebellum in saccadic adaptation as a window into neural mechanisms of motor learning
Authors: Prsa Mario , Thier Peter 
Published: June 2011

AbstractHow does the nervous system guide the muscular periphery during the acquisition of a new motor skill? This is a fundamental question for researchers trying to understand the neural basis of motor learning. Recent advances in studying a valuable example of short‐term motor learning, namely the adaptation of saccadic eye movements, have revealed neuronal processes in the cerebellum that underlie the unfolding of the learned behavior. In this review, we describe the latest findings from electrophysiology studies of saccadic adaptation and how they can generalize to more elaborate examples of cerebellum‐dependent adaptation of movements. We focus our discussion on the plastic changes that are observed in the firing properties of Purkinje cells during the acquisition of the wanted motor response and describe how the altered activity of these neurons modifies the dynamics of the cerebellar microcircuitry. We finally demonstrate how such task‐related modifications in the cerebellum are appropriate to fine‐tune extracerebellar pre‐motor structures and induce the learned behavior.
Control from below: the role of a midbrain network in spatial attention
Authors: Knudsen Eric I. 
Published: June 2011

AbstractSpatial attention enables the brain to analyse and evaluate information selectively from a specific location in space, a capacity essential for any animal to behave adaptively in a complex world. We usually think of spatial attention as being controlled by a frontoparietal network in the forebrain. However, emerging evidence shows that a midbrain network also plays a critical role in controlling spatial attention. Moreover, the highly differentiated, retinotopic organization of the midbrain network, especially in birds, makes it amenable to detailed analysis with modern techniques that can elucidate circuit, cellular and synaptic mechanisms of attention. The following review discusses the role of the midbrain network in controlling attention, the neural circuits that support this role and current knowledge about the computations performed by these circuits.