bluuebunny/crossref_metadata_2025 huggingface dataset:
Dielectric spectroscopy for probing the relaxation and charge transport in polypyrrole nanofibers
Authors: Banerjee Somik , Kumar A.
Published: June 2011

Conductivity relaxation and charge transport mechanisms in polypyrrole (PPy) nanofibers synthesized using a micellar polymerization technique with varying surfactant concentration has been investigated by dielectric relaxation spectroscopy. TEM micrographs depict that the increasing surfactant concentration leads to the reduction of the nanofiber diameter. X-ray diffraction studies show that domain length in the PPy nanofibers decreases with decreasing fiber diameter whereas the strain caused due to dislocations and point defects increases. The permittivity spectra reveal that the relaxation mechanism in PPy nanofibers are dominated by hopping of trapped charges. Two relaxation peaks in the impedance spectra are attributed to the two-phase structure in the PPy nanofibers; the lower frequency peak is ascribed to the phase of oxidized repeat units and the higher frequency peak to the reduced repeat units of PPy nanofibers. The occurrence of relaxation peaks at different frequencies in the impedance and modulus spectra indicates a non-Debye relaxation with a wide distribution of relaxation times. The ac conductivity has been interpreted as a power law of frequency. The decrease of the parameter s with increasing temperature indicates that correlated barrier hopping is the dominant charge transport mechanism. Existence of polarons as major charge carriers has been confirmed by the low values of polaron binding energy.
Defect levels of semi-insulating CdMnTe:In crystals
Authors: Kim K. H. , Bolotinikov A. E. , Camarda G. S. , Hossain A. , Gul R. , Yang G. , Cui Y. , Prochazka J. , Franc J. , Hong J. , James R. B.
Published: June 2011

Using photoluminescence (PL) and current deep-level transient spectroscopy (I-DLTS), we investigated the electronic defects of indium-doped detector-grade CdMnTe:In (CMT:In) crystals grown by the vertical Bridgman method. We similarly analyzed CdZnTe:In (CZT:In) and undoped CdMnTe (CMT) crystals grown under the amount of same level of excess Te and/or indium doping level to detail the fundamental properties of the electronic defect structure more readily. Extended defects, existing in all the samples, were revealed by synchrotron white beam x-ray diffraction topography and scanning electron microscopy. The electronic structure of CMT is very similar to that of CZT, with shallow traps, A-centers, Cd vacancies, deep levels, and Te antisites. The 1.1-eV deep level, revealed by PL in earlier studies of CZT and CdTe, were attributed to dislocation-induced defects. In our I-DLTS measurements, the 1.1-eV traps showed different activation energies with applied bias voltage and an exponential dependence on the trap-filling time, which are typical characteristics of dislocation-induced defects. We propose a new defect-trap model for indium-doped CMT crystals.
Blast wave and contraction in Au(111) thin film induced by femtosecond laser pulses. A time resolved x-ray diffraction study.
Authors: Chen Jie , Chen Wei-Kan , Rentzepis Peter M.
Published: June 2011

We utilize 100 fs optical pulses as a means of heating 150 nm thick single Au (111) crystals, below the melting point and monitor the subsequent structural evolution with subpicosecond time resolution using 0.6 ps, 8.04 KeV x-ray pulses. By monitoring the energy and time dependent modulation of the width and shift of the x-ray diffraction rocking curve, we have obtained information on electron-phonon coupling, photon-lattice interaction, and time resolved kinetics of the crystal disorder. The data show that during the first couple picoseconds after optical excitation, the formation of a “blast force” and lattice contraction, followed by a pressure wave formed 10-20 ps later. Both the blast and pressure wave propagate through the crystal with sonic velocities. These time resolved x-ray diffraction data provide a detail description of the processes induced by ultrafast laser pulses impinging on very thin metallic crystals.
Type-II core/shell nanoparticle induced photorefractivity
Authors: Li Xiangping , Van Embden Joel , Evans Richard A. , Gu Min
Published: June 2011

We demonstrate engineering the photocharge generation efficiency of nanoparticles on the nanometer scale by using a type-II band-gap structure. Compared to bare CdSe cores, the dispersion of type-II core/shell nanoparticles in photorefractive polymer led to an average 100% increase in photocurrents. An improvement to the refractive-index construction time, and a near 100% enhancement to the two beam coupling net-gain coefficients and four-wave mixing internal diffraction efficiencies have been achieved at moderate biases.
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

Populations 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.
Relaxation of low-temperature magnetoresistance and magnetization of polycrystalline (La0.5Eu0.5)0.7Pb0.3MnO3
Authors: Shaykhutdinov K A , Balaev D A , Semenov S V , Popkov S I , Dubrovskiy A A , Sapronova N V , Volkov N V
Published: June 2011

Hysteresis and relaxation of magnetoresistance and magnetization of substituted (La0.5Eu0.5)0.7Pb0.3MnO3 lanthanum manganite in a low-temperature region (<40 K) are investigated. It is shown that at these temperature features of the magnetoresistive effect are determined mainly by spin-dependent tunnelling of carriers via insulating grain boundaries. As was demonstrated previously, the grain boundaries may be antiferromagnetically ordered. Therefore, relaxation of magnetization and resistance is determined by the processes of relative orientation of the magnetic moments of ferromagnetic domains neighbouring the antiferromagnetic boundary of ferromagnetic domains under the action of temperature fluctuations. It is shown that relaxation follows the logarithmic law within the time interval t ∼ 102–3×103 s. A comparison between time evolutions of the magnetic moment and resistance shows that magnetoresistance and magnetization are related as δR = δM

n
, where n = 2.5. The obtained value n is close to the characteristic value n = 2 for tunnel magnetoresistance of granular ferromagnetic metal/insulator systems.
From conjugacy classes in the Weyl group to unipotent classes
Authors: Lusztig G.
Published: June 2011

LetGGbe a connected reductive algebraic group over an algebraic closed field. We define a (surjective) map from the set of conjugacy classes in the Weyl group to the set of unipotent classes inGG.
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.
Social environment determines degree of chemical signalling
Authors: Steiger Sandra , Haberer Wolf , Müller Josef K.
Published: June 2011

Few studies have attempted to distinguish between cues and signals in the context of chemical communication. A number of chemical substances have been shown to vary with physiological state, such as stage of oestrus cycle, fertility, dominance status or nutritional condition, but little is known about whether this variation is incidental or adaptive. Here, we provide evidence of a substance whose emission varies with breeding state, but is not merely an incidental by-product of physiological state, but rather, an evolved signal. Breeding females of the facultative biparental burying beetle,
Nicrophorus vespilloides
, release methyl geranate, a substance that helps males to identify breeding status and to distinguish between their female partners and non-breeding intruders. We demonstrate that females respond flexibly to their social environment and emit high amounts of methyl geranate only in the presence of a male partner, i.e. a receiver. In contrast, cuticular hydrocarbons, which also have been shown to change with breeding status, are not modulated and do not differ between single and paired breeding females. Receiver-dependent chemical signalling is expected to evolve when costs are involved in the production or transmission of the signal; such signal modulation might be more common than previously thought.
Presidential politics: The controversial election of 1945
Authors: Collins Peter
Published: June 2011

A change of leadership is an opportunity for an organization to review its values and objectives and, perhaps, set a new course for itself. As World War II was drawing to a close in 1945, the Royal Society was faced with such an opportunity, having to select not only a new President in succession to Henry Dale but also two new Officers. Many within and beyond the Society were keenly interested in the outcome. Almost 20% of the Fellowship, spurred on by Percy Andrade, signed a petition setting out for the benefit of Council where the Society should be heading and the attributes that the incoming President would need to lead it there. The petitioners' vision proved somewhat controversial, but more controversial was their action in seeking to influence Council directly rather than leaving things to take their normal discreet course. In the end they won the argument but lost the battle. The episode is revealing of the Society's values and culture at the time.
Generalized methods and solvers for noise removal from piecewise constant signals. II. New methods
Authors: Little Max A. , Jones Nick S.
Published: June 2011

Removing noise from signals which are piecewise constant (PWC) is a challenging signal processing problem that arises in many practical scientific and engineering contexts. In the first paper (part I) of this series of two, we presented background theory building on results from the image processing community to show that the majority of these algorithms, and more proposed in the wider literature, are each associated with a special case of a generalized functional, that, when minimized, solves the PWC denoising problem. It shows how the minimizer can be obtained by a range of computational solver algorithms. In this second paper (part II), using this understanding developed in part I, we introduce several novel PWC denoising methods, which, for example, combine the global behaviour of mean shift clustering with the local smoothing of total variation diffusion, and show example solver algorithms for these new methods. Comparisons between these methods are performed on synthetic and real signals, revealing that our new methods have a useful role to play. Finally, overlaps between the generalized methods of these two papers and others such as wavelet shrinkage, hidden Markov models, and piecewise smooth filtering are touched on.
Fixed and dilutable benefits: female choice for good genes or fertility
Authors: Tazzyman Samuel J. , Seymour Robert M. , Pomiankowski Andrew
Published: June 2011

Benefits accruing to females who exercise mate choice have been defined to be either ‘direct’ or ‘indirect’. We suggest an alternative distinction: benefits can be considered ‘fixed’, meaning they are on average equal to all females mating with the same male (e.g. good genes' benefits) or ‘dilutable’, meaning they are shared between females mating with the same male, so that the more mates a male has, the lower the average benefit to each (e.g. fertility benefits or many forms of direct benefit). Using a simple model, we show that this distinction has a major effect on the form of female preference. We predict that mating skew will be far greater in species where the benefits are fixed when compared with those where the benefits are dilutable.
Cambrian stalked echinoderms show unexpected plasticity of arm construction
Authors: Zamora S. , Smith A. B.
Published: June 2011

Feeding arms carrying coelomic extensions of the theca are thought to be unique to crinoids among stemmed echinoderms. However, a new two-armed echinoderm from the earliest Middle Cambrian of Spain displays a highly unexpected morphology. X-ray microtomographic analysis of its arms shows they are polyplated in their proximal part with a dorsal series of uniserial elements enclosing a large coelomic lumen. Distally, the arm transforms into the more standard biserial structure of a blastozoan brachiole. Phylogenetic analysis demonstrates that this taxon lies basal to rhombiferans as sister-group to pleurocystitid and glyptocystitid blastozoans, drawing those clades deep into the Cambrian. We demonstrate that Cambrian echinoderms show surprising variability in the way their appendages are constructed, and that the appendages of at least some blastozoans arose as direct outgrowths of the body in much the same way as the arms of crinoids.
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

A 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

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

Global 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

The 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

Overwintering 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

In 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

How 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

Spatial 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.
A perceptual discrimination task abnormally facilitates reflexive saccades in Parkinson’s disease
Authors: van Stockum Saskia , MacAskill Michael R. , Myall Daniel , Anderson Tim J.
Published: June 2011

Numerous studies have shown that Parkinson’s disease (PD) affects the ability to generate voluntary saccades and the ability to suppress reflexive saccades. The effects of PD on the generation of reflexive saccades, however, are not clear. Some studies report impairments, but there are also reports of abnormal facilitation or hyper‐reflexivity of the saccade system in PD. Meanwhile, it has been reported that the concurrent performance of a perceptual discrimination task facilitates saccade initiation and reduces saccade latencies in healthy subjects [A. Montagnini & L. Chelazzi (2005)Vis. Res., 45, 3391–3401; L. Trottier & J. Pratt (2005)Vis. Res., 45, 1349–1354]. To investigate the circumstances under which the saccade system may appear hyper‐reflexive in PD, we compared reflexive saccades with and without a concurrent perceptual discrimination task in 20 PD patients and 20 controls. Without the discrimination task, the PD group produced reflexive saccades at normal latencies. The discrimination task reduced saccade latencies more in the PD group than in the control group, resulting in abnormally short mean reflexive saccade latencies in the PD group. The discrimination task increased saccade gain in both groups, but saccades in the PD group remained hypometric as compared with saccades in the control group. We conclude that the attentional demands of this paradigm revealed a hypersensitivity to visual inputs in the PD group.
Minimum Income Standards in Israel: A Recent History in Economic and Humanistic Discourses
Authors: Monnickendam Menachem
Published: June 2011

Recent years have seen a growing interest in the creation of Minimum Income Standards (MIS). The impetus for this is the belief that governments that do not employ MIS to set income support can ultimately be persuaded to do so. Even as scholars recognize the many hurdles in the way of an MIS's acceptance, they nonetheless hope, and seem to expect, that the hurdles can be overcome and the political will be created to adopt empirical MIS that would allow a decent standard of living. This article, a case study analyzing the setting of income support levels in Israel over more than seven decades, questions this assumption. The analyses, anchored in Veit‐Wilson's notion of discourses, show that the absence of governmental MIS in Israel has not been incidental, but the outcome of repeated conscious decisions, anchored in the primacy of the asocial economistic discourse. This discourse, it shows, served as a strong disincentive to the adoption of governmental MIS, which would have required the government to justify its choice to set income support below that which was needed for a minimum standard of living.
Social Exclusion and Poverty: Translating Social Capital into Accessible Resources
Authors: Boon Bronwyn , Farnsworth John
Published: June 2011

This article investigates the dynamic multi‐dimensional processes through which the poor become excluded from social participation. Drawing on social capital literature, it traces how bridging and bonding capital do not always translate into expected levels of social participation. It does so by detailing research findings from low income focus groups undertaken in Dunedin, New Zealand. These describe the experiences of group members in attempting to manage connections around employment, their own broader social participation or the participation of their children. In each case, the study highlights the difficulties of translation they experienced: in particular, translating available bridging or bonding capital into useful social, cultural or economic resources which could mitigate their social exclusion or enable fuller social participation.
The application of prototype point processes for the summary and description of California wildfires
Authors: Nichols Kevin , Schoenberg Frederic Paik , Keeley Jon E. , Bray Andrew , Diez David
Published: June 2011

A method for summarizing repeated realizations of a space‐time marked point process, known as prototyping, is discussed and applied to catalogues of wildfires in California. Prototype summaries are constructed for varying time intervals using California wildfire data from 1990 to 2006. Previous work on prototypes for temporal and space‐time point processes is extended here to include methods for computing prototypes with marks and the incorporation of prototype summaries into hierarchical clustering algorithms, the latter of which is used to delineate fire seasons in California. Other results include summaries of patterns in the spatial‐temporal distribution of wildfires within each wildfire season.
Revolutionary Aesthetics? Kleist, 1968, and the New German Cinema
Authors: Allan Seán
Published: June 2011

This essay analyses the particular appeal of Kleist's work for the filmmakers of the New German Cinema movement in the Federal Republic during the late 1960s and early 1970s. Both Volker Schlöndorff'sKohlhaas – der Rebell(1968) and Hans‐Jürgen Syberberg'sSan Domingo(1970) invite the spectator to view the student movement and the political events of 1968 through the prism of Kleist'sMichael KohlhaasandDie Verlobung in St. Domingo. Although Schlöndorff's film attempts to launch a radical critique of Kohlhaas's individualistic quest, the reluctance to abandon an essentially conservative aesthetic is at odds with Schlöndorff's quasi‐Marxist reading of Kleist's novella. By contrast, theavant‐gardeaesthetic of Syberberg'sSan Domingorepresents an attempt to develop a visual correlate to the distinctive character of Kleist's prose fiction generally, and of his radical treatment of the San Domingan uprising in particular. WhileSan Domingoportrays the rise of such marginalised groups as the Rockers from Am Harras as a logical consequence of an increasing process of alienation from capitalist society, it also articulates a critique of left‐wing sentimentality in its portrayal of the central protagonist, Michael König.

Dieser Essay untersucht den besonderen Anreiz, den Kleists Werk für die westdeutschen Filmemacher des Neuen Deutschen Kinos der späten 60er und frühen 70er Jahre ausmacht. Sowohl Volker SchlöndorffsKohlhaas – der Rebell(1968) wie auch Hans‐Jürgen SyberbergsSan Domingo(1970) animieren den Zuschauer, jene Werke Kleists durch das Prisma der Studentenbewegung und der politischen Ereignisse von 1968 zu betrachten. Obwohl Schlöndorffs Film dazu intendiert, Kohlhaases rebellischen Alleingang vehement zu kritisieren, steht der grundsätzlich konservative Stil des Films in krassem Gegensatz zu Schlöndorffs quasi‐marxistischer Interpretation von Kleists Novelle. Hingegen unternimmt der avantgardistische Stil von SyberbergsSan Domingoden Versuch, ein visuelles Korrelat zum unverwechselbaren Charakter von Kleists Prosa‐Werken generell zu erstellen, gleichzeitig jedoch betont er die radikale Art und Weise, wie der San Dominikanische Aufstand bei Syberberg behandelt wird. WährendSan Domingoeinerseits den Aufstieg von Randgruppen wie etwa die Rocker von Am Harras als die logische Konsequenz angesichts einer wachsenden Entfremdung innerhalb eines kapitalistischen Systems aufzeigt, wird andererseits die Kritik gegenüber einer linkspolitischen Sentimentalität deutlich, wie sie z.B. durch den Hauptprotagonisten Michael König verkörpert wird.
Factors influencing unhealthy eating behaviour in US adolescents
Authors: Kinard Brian R. , Webster Cynthia
Published: June 2011

This research explores the simultaneous effects of key variables on unhealthy eating behaviour. Specifically, this study focuses on the relative effects of advertising, parental and peer influence, and self‐efficacy on the unhealthy eating behaviour of US adolescents. The results suggest that: (1) parental influence, peer influence and self‐efficacy significantly predict unhealthy eating behaviour; (2) self‐efficacy is the strongest predictor of unhealthy eating behaviour; and (3) advertising effects are largely neutralized by parental influence, peer influence and self‐efficacy.
Cytochrome P450 mediates dopamine formation in the brain in vivo
Authors: Bromek Ewa , Haduch Anna , Gołembiowska Krystyna , Daniel Władysława A.
Published: June 2011

J. Neurochem. (2011) 118, 806–815.

The cytochrome P450‐mediated synthesis of dopamine from tyramine has been shown in vitro. The aim of the present study was to demonstrate the ability of rat cytochrome P450 (CYP) 2D to synthesize dopamine from tyramine in the brain in vivo. We employed two experimental models using reserpinized rats with a blockade of the classical pathway of dopamine synthesis from tyrosine. Model A estimated dopamine production from endogenous tyramine in brain structures in vivo (ex vivo measurement of a tissue dopamine level), while Model B measured extracellular dopamine produced from exogenous tyramine (an in vivo microdialysis). In Model A, quinine (a CYP2D inhibitor) given intraperitoneally caused a significant decrease in dopamine level in the striatum and nucleus accumbens and tended to fall in the substantia nigra and frontal cortex. In Model B, an increase in extracellular dopamine level was observed after tyramine given intrastructurally (the striatum). After joint administration of tyramine and quinine, the amount of the dopamine formed was significantly lower compared to the group receiving tyramine only. The results of the two complementary experimental models indicate that the hydroxylation of tyramine to dopamine may take place in rat brain in vivo, and that CYP2D catalyzes this reaction.
Lateral epicondylalgia. A quantitative and qualitative analysis of interdisciplinary cooperation and treatment choice in the Swedish health care system
Authors: Nilsson Pia , Lindgren Eva‐Carin , Månsson Jörgen
Published: June 2011

Scand J Caring Sci; 2012; 26; 28–37

Lateral epicondylalgia. A quantitative and qualitative analysis of interdisciplinary cooperation and treatment choice in the Swedish health care system

Objective and aim:  Interdisciplinary cooperation is essential to develop a broad range of knowledge and skills. The aim of this study was to describe health care professionals’ treatment choices, their cooperation with other professionals and their perceptions of potential risks regarding treatments of acute lateral epicondylalgia (LE).

Design:  A quantitative descriptive study design with a summative approach to qualitative analysis.

Ethical issues:  The ethical committee was asked verbally for approval but, as this study was performed to develop an organised way to treat LE, it did not require approval. The four ethical aspects information, consent, confidentiality and the use of the study materials were all addressed.

Subjects:  All orthopaedic surgeons, general practitioners, physiotherapists and occupational therapists in a county.

Methods:  Questionnaire with 18 dichotomous, multiple‐response, multiple‐choice questions and three open‐ended questions were analysed using quantitative cross‐tab and qualitative content analysis with summative approach.

Results:  The most common treatment choices were Non Steroidal Anti Inflammatory Drugs (NSAID), corticosteroid injections, training programmes, braces and ergonomics. Advantages from interdisciplinary cooperation were higher rated than disadvantages. The qualitative findings dealt with perceptions of interdisciplinary cooperation and resulted in three categories; right level of care, increased quality of care and decreased quality of care. Almost half of the physicians felt potential risks associated with their treatment methods. The qualitative findings dealt with perceptions of the potential risks and resulted in two categories: side effects and inadequate treatment.

Study limitations:  The number of responses varied because some of the respondents did not answered all of the questions.

Conclusion:  Interdisciplinary cooperation in the treatment of patients with acute LE benefits the patients by shortening the rehabilitation period and provides health care professionals the opportunity for an improved learning and exchanging experiences. These basic conditions must be met to improve health care quality.
Complete Epicardial Resynchronization Device Implantation in a Patient Who Underwent a Replacement of Mitral and Tricuspid Valve
Authors: RICCIARDI DANILO , ASMUNDIS CARLO DE , CZAPLA JENS , LA MEIR MARK , BRUGADA PEDRO , WELLENS FRANCIS
Published: June 2011

A 71‐year‐old woman with severe nonischemic dilated cardiomyopathy and low ejection fraction with severe mitral regurgitation and tricuspid regurgitation and pulmonary hypertension underwent multiple valve repairs and cardiac resynchronization therapy implantation with epicardial shock leads. (PACE 2013; 36:e56–e58)
Importance of optimal dosing ≥30 mg/kg/d during deferasirox treatment: 2.7‐yr follow‐up from the ESCALATOR study in patients with β‐thalassaemia
Authors: Taher Ali , Elalfy Mohsen S. , Al Zir Kusai , Daar Shahina , Al Jefri Abdullah , Habr Dany , Kriemler‐Krahn Ulrike , El‐Ali Ali , Roubert Bernard , El‐Beshlawy Amal
Published: June 2011

Following 1‐yr deferasirox therapy in the ESCALATOR study, 57% of previously chelated patients with β‐thalassaemia achieved treatment success (maintenance of or reduction in liver iron concentration (LIC) vs. baseline LIC). Seventy‐eight per cent had dose increases at median of 26 wk, suggesting that 1‐yr results may not have reflected full deferasirox efficacy. Extension data are presented here. Deferasirox starting dose was 20 mg/kg/d (increases to 30/40 mg/kg/d permitted in the core/extension, respectively). Efficacy was primarily assessed by absolute change in LIC and serum ferritin. Overall, 231 patients received deferasirox in the extension; 67.4% (P < 0.0001) achieved treatment success. By the end of the extension, 66.2% of patients were receiving doses ≥30 mg/kg/d. By the end of the 1‐yr extension, mean LIC had decreased by 6.6 ± 9.4 mg Fe/g dw (baseline 19.6 ± 9.2; P < 0.001) and median serum ferritin by 929 ng/mL (baseline 3356; P < 0.0001). There was a concomitant improvement in liver function markers (P < 0.0001). Fewer drug‐related adverse events were reported in extension than core study (23.8% vs. 44.3%). Doses ≥30 mg/kg/d were generally required because of high transfusional iron intake and high baseline serum ferritin levels, highlighting the importance of administering an adequate dose to achieve net negative iron balance.
The association of heavy and light chain variable domains in antibodies: implications for antigen specificity
Authors: Chailyan Anna , Marcatili Paolo , Tramontano Anna
Published: June 2011

The antigen‐binding site of immunoglobulins is formed by six regions, three from the light and three from the heavy chain variable domains, which, on association of the two chains, form the conventional antigen‐binding site of the antibody. The mode of interaction between the heavy and light chain variable domains affects the relative position of the antigen‐binding loops and therefore has an effect on the overall conformation of the binding site. In this article, we analyze the structure of the interface between the heavy and light chain variable domains and show that there are essentially two different modes for their interaction that can be identified by the presence of key amino acids in specific positions of the antibody sequences. We also show that the different packing modes are related to the type of recognized antigen.
Study of Human Dopamine Sulfotransferases Based on Gene Expression Programming
Authors: Si Hongzong , Zhao Jiangang , Cui Lianhua , Lian Ning , Feng Hanlin , Duan Yun‐Bo , Hu Zhide
Published: June 2011

A quantitative model is developed to predict the Km of 47 human dopamine sulfotransferases by gene expression programming. Each kind of compound is represented by several calculated structural descriptors of moment of inertia A, average electrophilic reactivity index for a C atom, relative number of triple bonds, RNCG relative negative charge, HA‐dependent HDSA‐1, and HBCA H‐bonding charged surface area. Eight fitness functions of the gene expression programming method are used to find the best nonlinear model. The best quantitative model with squared standard error and square of correlation coefficient are 0.096 and 0.91 for training data set, and 0.102 and 0.88 for test set, respectively. It is shown that the gene expression programming‐predicted results with fitness function are in good agreement with experimental ones.