bluuebunny/crossref_metadata_2025 huggingface dataset:
Infection dynamics of two renal myxozoans in hatchery reared fry and juvenile Atlantic cod Gadus morhua L.
Authors: HOLZER A. S. , STEWART S. , TILDESLEY A. , WOOTTEN R. , SOMMERVILLE C.
Published: May 2010

In order to study the infection dynamics of 2 renal myxozoans, Zschokkella hildae Auerbach, 1910 and Gadimyxa atlanticaKøie, Karlsbakk and Nylund, 2007 in cultured Atlantic cod, Gadus morhua L. aged 3–19 months, a specific single-round PCR assay and a double-label in situ hybridization protocol were developed. The results demonstrated that the 2 myxozoans show spatial separation of their development with regard to spore formation inside the renal tubules versus the collecting ducts and ureters, as well as temporal separation with Z. hildae proliferating and developing spores only once the G. atlantica infection decreases, despite the presence of both myxozoans in the smallest fry studied. These results strongly suggest within-host competition of the 2 myxozoans with potential suppression of Z. hildae by G. atlantica until G. morhua acquires immunity against G. atlantica. The quantification of the G. atlantica infection inside the renal tubules before and after a 29-day experimental growth performance study using fry from hatcheries with differing filtration systems showed that the intensity of infection with G. atlantica seems to be controlled if prolonged exposure to the myxozoan transmission stages takes place from hatching onwards. Surprisingly, growth rates in the trial were inversely affected suggesting that G. atlantica does not negatively influence cod fry growth performance.
Parasitism underground: determinants of helminth infections in two species of subterranean rodents (Octodontidae)
Authors: ROSSIN M. A. , MALIZIA A. I. , TIMI J. T. , POULIN R.
Published: May 2010

Patterns of infection among hosts in a population are often driven by intrinsic host features such as age or sex, as well as by positive or negative interactions between parasite species. We investigated helminth parasitism in 2 South American rodent species,Ctenomys australisandC. talarum(Octodontidae), to determine whether the unusual solitary and subterranean nature of these hosts would impact their patterns of infection. We applied generalized linear models to infection data on a total of 7 helminth species (1 inC. australisand 6 inC. talarum). Host age and season of capture influenced infection levels in some of the helminth species, but none were influenced by host body condition. InC. talarum, 4 pairs of helminth species showed significant associations, either asymmetrical or symmetrical, and with 3 of the 4 being positive; strong inter-specific facilitation appears likely in 1 case. Also, we found that female hosts, especially non-pregnant ones, harboured heavier infections of 2 nematode species than male hosts. This is in sharp contrast to the general male-bias reported for most studies of nematodes in wild mammals, and we develop explanations for these results based on the unusual ecology of these subterranean rodents.
Isolation of Trypanosoma caninum in domestic dogs in Rio de Janeiro, Brazil
Authors: DE S. PINTO A. G. , SCHUBACH T. M. P. , FIGUEIREDO F. B. , BAPTISTA C. , FAGUNDES A. , DA S. BARROS J. H. , DE PAULA C. C. , TOMA H. K. , MADEIRA M. F.
Published: May 2010

The domestic dog's involvement with different members of the Trypanosomatidae family has been the focus of several studies due to this animal's close proximity to man. Recently this animal has been infected by a new Trypanosoma species (T. caninum), described in Rio de Janeiro and 19 similar isolates were later obtained. The objective of this study was to identify these isolates. All samples were isolated from intact skin cultures and analysed morphologically, by biochemical isoenzyme electrophoresis assays and by several molecular PCR assays. Additionally, anti-Leishmania sp. antibodies were assessed using the indirect Immunofluorescence Antibody Test (IFAT) in all animals. The methodologies employed to identify the isolates, including partial nucleotide sequences of 18S rRNA gene, indicated patterns identical to T. caninum and patterns different from the other species, including T. cruzi and T. rangeli samples. A phylogenetic tree constructed with the partial 18S ribosomal sequence shows that T. caninum is clustered with T. pestanai. Ten (52·6%) animals presented anti-Leishmania sp. antibodies with titres varying from 1:40 to 1:320. Thus, the hypothesis that this protozoan has disseminated among the dogs in Rio de Janeiro must be considered. The importance of a correct diagnosis in those animals and the possible consequences in the areas where visceral leishmaniasis is found are discussed here.
Aggregation patterns of macroendoparasites in phylogenetically related fish hosts
Authors: MARQUES J. F. , SANTOS M. J. , CABRAL H. N.
Published: May 2010

Macroparasites are generally aggregated within their hosts with infection and aggregation levels resulting from a continuous arms race between maintaining high mating probability and host mortality low for which host and environmentally related factors contribute to some extent. Here, infection and aggregation patterns of the macroendoparasites infecting the flatfish Citharus linguatula, Arnoglossus laterna, Lepidorhombus boscii, Scophthalmus rhombus and Platichthys flesus in 3 areas along the Portuguese coast were analysed. Of the 21 macroendoparasite species found only 1 infected all hosts and most were host or area exclusive. For each host-parasite system, values of the indices varied between areas and macroendoparasites were not always aggregated; in fact, some macroendoparasites were generally uniformly distributed, which can be related to specific density-dependent regulation mechanisms. No general pattern was found for infection or aggregation levels of the 3 species infecting more than 2 hosts along the Portuguese coast, i.e. Lecithochirium rufoviride, Nybelinia lingualis and Anisakis simplex s.l., suggesting that regulation mechanisms are not species specific but are locally determined, with host ecology playing a significant role.
Consequences of microhabitat selection for reproductive success in the parasitic copepodNeobrachiella spinicephala(Lernaeopodidae)
Authors: TIMI J. T. , LANFRANCHI A. L. , POULIN R.
Published: May 2010

Narrow site specificity in parasites is assumed to be associated with fitness benefits, such as higher reproductive success, although this is never quantified. We linked the body mass and combined mass of egg sacs of female copepods,Neobrachiella spinicephala, parasitic on the sandperch,Pinguipes brasilianus, to attachment sites on the host. Adult females attach permanently either on the lips, the margins of the operculum, or the base of pectoral or pelvic fins. In addition to influences of sampling site, season and host body length, our analyses revealed important fitness effects. First, attachment site significantly influenced copepod body mass; independent of other factors, copepods at the base of fins were 32% larger than those on the lips or operculum. Second, the mass of egg sacs was almost always greater if the copepod was attached at the base of fins rather than to the lip or operculum. Thus, a female weighing 6 mg would, on average, produce 40% larger egg sacs if attached to the base of fins. However, copepods were much more likely to attach at the base of fins on small fish, and on either the lip or the operculum on large fish. We propose that constraints varying with fish size account for the shift from optimal to suboptimal attachment sites as a function of increasing host size. By measuring differences in fitness components between attachment sites, our approach allows hypothesis testing regarding microhabitat selection.
Mechanisms of vaccine adjuvanticity at mucosal surfaces
Authors: Foss Dennis L. , Murtaugh Michael P.
Published: May 2010

The vast majority of pathogens invade via mucosal surfaces, including those of the intestine. Vaccination directly on these surfaces may induce local protective immunity and prevent infection and disease. Although vaccine delivery to the gut mucosa is fraught with obstacles, immunization can be enhanced using adjuvants with properties specific to intestinal immunity. In this review, we present three general mechanisms of vaccine adjuvant function as originally described by Freund, and we discuss these principles with respect to intestinal adjuvants in general and to the prototypical mucosal adjuvant, cholera toxin. The key property of intestinal adjuvants is to induce an immunogenic context for the presentation of the vaccine antigen. The success of oral vaccine adjuvants is determined by their ability to induce a controlled inflammatory response in the gut-associated lymphoid tissues, characterized by the expression of various costimulatory molecules and cytokines. An understanding of the specific molecular mechanisms of adjuvanticity in the gut will allow the rational development of safe and effective oral vaccines.
Vaccines against the avian enteropathogensEimeria,CryptosporidiumandSalmonella
Authors: Lillehoj Erik P. , Yun Cheol H. , Lillehoj Hyun S.
Published: May 2010

The worldwide poultry industry provides a substantial proportion of the nutritional requirement of the human population. To keep pace with the increasing demand for the high-quality, low-cost protein source that poultry provides, intensive rearing practices have been developed within the past few decades. For example, chickens are housed routinely in crowded environments under adverse conditions, and genetic strains have been selected for rapid growth, high protein-to-fat content and superior egg-laying characteristics. A major negative consequence of these practices has been an increase in the incidence of diseases. Enteric diseases in particular have emerged as a major problem threatening the future viability of the poultry industry. A variety of methods have been used to combat avian diseases in the commercial setting, including improved farm management practices, the use of antibiotic drugs, the selection of disease-resistant strains of chickens, and the manipulation of the chicken’s immune system. In the latter category, the development of vaccines against the major avian diseases has become a priority in the poultry industry. This review will highlight recent progress in vaccine development against three major avian enteric pathogens:Eimeria,CryptosporidiumandSalmonella.
Swine vesicular disease virus. Pathology of the disease and molecular characteristics of the virion
Authors: Escribano-Romero Estela , Jiménez-Clavero Miguel Angel , Ley Victoria
Published: May 2010

Swine vesicular disease is a highly contagious disease of pigs that is caused by an enterovirus of the family Picornaviridae. The virus is a relatively recent derivative of the human coxsackievirus B5, with which it has high molecular and antigenic homology. The disease is not severe, and affected animals usually show moderate general weakening and slight weight loss that is recovered in few days, as well as vesicular lesions in the mucosa of the mouth and nose and in the interdigital spaces of the feet. However, the similarity of these lesions to those caused by foot-and-mouth disease virus has led to the inclusion of this virus in list A of the Office International des Epizooties. The disease has been eradicated in the European Union except in Italy, where it is considered endemic in the south. Nevertheless, as occasional outbreaks still appear and must be eliminated rapidly, European countries are on the alert and farms are monitored routinely for the presence of the virus. This circumstance has led to a considerable effort to study the pathology of the disease and the molecular biology and antigenicity of the virus, and to the development of optimized methods for the diagnosis of the infection.
Military Psychology in Switzerland
Authors: Annen Hubert , Seiler Stefan , Jonas Klaus
Published: May 2010

Selection, assessment, motivation, stress, and leadership are the central research and application fields of military psychology. The Swiss Armed Forces have worked in these fields since the 1920s. However, military psychology has only been instituted in Switzerland officially since the mid-1990s. Psychologists and educators in the Psychological-Pedagogical Service of the Armed Forces give counseling and guidance to soldiers and cadre alike, while in the recruitment centers psychologically trained personnel maintain a high quality in psychological testing. Military psychological research is conducted mainly at the Swiss Military Academy at ETH Zurich (MILAK/ETHZ). The articles in this Special Issue are connected directly to the pertinent research in the fields of selection, training, and education of cadre in the Swiss Armed Forces.
Officer Selection for the Swiss Armed Forces
Authors: Melchers Klaus G. , Annen Hubert
Published: May 2010

The present study (N = 844) examined the predictive validity and fairness of the assessment center (AC) and the general mental ability (GMA) test used to select officers for the Swiss Armed Forces. We found that both selection methods predicted candidates’ academic and military performance at the end of their officer training. Furthermore, the AC had incremental validity beyond GMA, meaning that it cannot be replaced by the GMA test. Concerning the fairness of the selection methods, no significant performance differences were found between candidates from the different Swiss language regions. With one exception, no evidence for differential prediction was found, and for the single exception, the selection procedure used was not the source of the differential prediction. Thus, the AC and the GMA test were generally equally predictive for candidates from the German-speaking region as well as from the two other language regions of Switzerland. Taken together, the present study attests to the good predictive validity and fairness of the methods used to select officers.
Appreciation at Work in the Swiss Armed Forces
Authors: Stocker Désirée , Jacobshagen Nicola , Semmer Norbert K. , Annen Hubert
Published: May 2010

This study explores the impact of appreciation at work among military professionals. Based on the concept of “Stress-as-Offense-to-Self” ( Semmer, Jacobshagen, Meier, & Elfering, 2007 ), appreciation is a possible resource due to boosts to self-esteem. We measured appreciation at work with a scale differentiating several forms and sources of appreciation. Data were gathered by an online survey of 228 male career officers and career noncommissioned officers of the Swiss Armed Forces. Appreciation at work correlated positively with job satisfaction and negatively with feelings of resentment. Moreover, appreciation at work explained incremental variance over and above job control, social support, and interactional justice. These results underline its distinction from other resource variables. Legal employment conditions of the military professionals include working hours in accordance with ongoing requirements without upper limits established. Moderator analysis showed that appreciation buffered the effect of long working hours on job satisfaction. Furthermore, appreciation mediated the effect of illegitimate tasks on job satisfaction as well as on feelings of resentment. Overall, these findings imply that it is worth building an organisational culture based on appreciation at work. Implications for research and military training are discussed.
Characterization of the biological effects of a novel protein kinase D inhibitor in endothelial cells
Authors: Evans Ian M. , Bagherzadeh Azadeh , Charles Mark , Raynham Tony , Ireson Chris , Boakes Alexandra , Kelland Lloyd , Zachary Ian C.
Published: May 2010

VEGF (vascular endothelial growth factor) plays an essential role in angiogenesis during development and in disease largely mediated by signalling events initiated by binding of VEGF to its receptor, VEGFR2 (VEGF receptor 2)/KDR (kinase insert domain receptor). Recent studies indicate that VEGF activates PKD (protein kinase D) in endothelial cells to regulate a variety of cellular functions, including signalling events, proliferation, migration and angiogenesis. To better understand the role of PKD in VEGF-mediated endothelial function, we characterized the effects of a novel pyrazine benzamide PKD inhibitor CRT5 in HUVECs (human umbilical vein endothelial cells). The activity of the isoforms PKD1 and PKD2 were blocked by this inhibitor as indicated by reduced phosphorylation, at Ser916 and Ser876 respectively, after VEGF stimulation. The VEGF-induced phosphorylation of three PKD substrates, histone deacetylase 5, CREB (cAMP-response-element-binding protein) and HSP27 (heat-shock protein 27) at Ser82, was also inhibited by CRT5. In contrast, CRT6, an inactive analogue of CRT5, had no effect on PKD or HSP27 Ser82 phosphorylation. Furthermore, phosphorylation of HSP27 at Ser78, which occurs solely via the p38 MAPK (mitogen-activated protein kinase) pathway, was also unaffected by CRT5. In vitro kinase assays show that CRT5 did not significantly inhibit several PKC isoforms expressed in endothelial cells. CRT5 also decreased VEGF-induced endothelial migration, proliferation and tubulogenesis, similar to effects seen when the cells were transfected with PKD siRNA (small interfering RNA). CRT5, a novel specific PKD inhibitor, will greatly facilitate the study of the role of PKD signalling mechanisms in angiogenesis.
An investigation of electromigration induced void nucleation time statistics in short copper interconnects
Authors: Dwyer V. M.
Published: May 2010

The stress evolution model (SEM) of Korhonenet al., is used to calculate the void nucleation time in a large number of short interconnects (lengths up to 50 μm). Finite element calculations show that the effect of the nonlinearity in the SEM model is small, and that a mesh size of the order of the grain size is quite adequate to give accurate simulation results. Via failure is the only mode considered in the current calculations, however the gain in simulation time over other solution methods means that more complex situations, possibly including void dynamics, may be modeled in future in this way. Using normal mass-lumping methods the analysis is isomorphic to the voltage development on a random RC chain, so standard methods from very large scale integrated static timing analysis may be used to obtain dominant time constants at each mesh point. This allows the distribution of nucleation times to be obtained as a function of the distributions of line parameters. Under the assumption of a lognormal grain size distribution and a normal distribution of diffusion activation energies, the nucleation time distribution is shown to be close to lognormal.
Neutron scattering study of internal void structure in RDX
Authors: Stoltz Chad A. , Mason Brian P. , Hooper Joe
Published: May 2010

We present the first small and ultrasmall angle neutron scattering (SANS/USANS) measurements of the internal void morphology of the high explosive RDX on length scales from 10 Å to 20 μm. Measurements were taken on a range of RDX samples with similar densities and particle size distributions but which have significantly different sensitivities to shock initiation as measured by large-scale gap tests of the samples when formulated in standard polymer blends. Scattering measurements were performed using a contrast match technique to eliminate all features apart from internal void structures. The dominant feature in all samples is a surface fractal scattering that extends from ∼50 nm to above 20 μm, with no observable upper bound for the fractal correlation length. These features are interpreted in terms of scattering from rough surfaces of interior air-filled voids with fractal dimensionality between 2.4 and 2.9. The fractal pattern is proposed to arise from complex growth patterns on void surfaces as internal solvent diffuses out of the crystallites. No evidence of distinct nanometer-scale voids is observed in any of our RDX samples. The neutron scattering invariant calculated over the measured SANS and USANS range, a gauge of the volume fraction of voids smaller than 20 μm, tracks well with sensitivity testing of the materials.
Sputtering-induced Co formation in x-ray photoelectron spectroscopy of nanocrystalline Zn1-xCoxO spinodal enrichment models
Authors: White Michael A. , Lovejoy Tracy C. , Ochsenbein Stefan T. , Olmstead Marjorie A. , Gamelin Daniel R.
Published: May 2010

Nanoscale enrichments resulting from spinodal decomposition have been proposed to contribute to the interesting magnetic properties of diluted magnetic oxides such as cobalt-doped ZnO (Zn1-xCoxO), but little is known experimentally about the electronic structures or physical properties of such enrichments. Here, x-ray photoelectron spectroscopy (XPS) is used to examine wurtzite Zn1-xCoxO crystallites over the full composition range (0.0≤x≤1.0) that serve as models of the proposed spinodal decomposition nanostructures within Zn1-xCoxO bulk materials. With increasing x, the valence band edge shifts to smaller binding energies and the cobalt 2p peaks shift to greater binding energies, providing spectroscopic signatures that may allow identification of spinodal decomposition in bulk Zn1-xCoxO. Reduction of Co2+ to Co0 by argon ion (Ar+) sputtering was also found to become markedly more facile with increasing x, suggesting that locally-enriched Zn1-xCoxO is at greater risk of yielding false-positive Co0 XPS signals than uniformly dilute Zn1-xCoxO with the same overall composition.
Influence of band bending and polarization on the valence band offset measured by x-ray photoelectron spectroscopy
Authors: Xu Xiaoqing , Liu Xianglin , Guo Yan , Wang Jun , Song Huaping , Yang Shaoyan , Wei Hongyuan , Zhu Qinsheng , Wang Zhanguo
Published: May 2010

The influence of band bending and polarization on the valence band offset measured by x-ray photoelectron spectroscopy (XPS) is discussed, and a modification method based on a modified self-consistent calculation is proposed to eliminate the influence and thus increasing the precision of XPS. Considering the spontaneous polarization at the surfaces and interfaces and the different positions of Fermi levels at the surfaces, we compare the energy band structures of Al/Ga-polar AlN/GaN and N-polar GaN/AlN heterojunctions, and give corrections to the XPS-measured valence band offsets. Other AlN/GaN heterojunctions and the piezoelectric polarization are also introduced and discussed in this paper.
Temporal evolution of electron density and temperature in capillary discharge plasmas
Authors: Oh Seong Y. , Uhm Han S. , Kang Hoonsoo , Lee In W. , Suk Hyyong
Published: May 2010

Time-resolved spectroscopic measurements of a capillary discharge plasma of helium gas were carried out to obtain detailed information about dynamics of the discharge plasma column, where the fast plasma dynamics is determined by the electron density and temperature. Our measurements show that the electron density of the capillary plasma column increases sharply after gas breakdown and reaches its peak of the order of 1018 cm−3 within less than 100 ns, and then it decreases as time goes by. The result indicates that a peak electron density of 2.3×1018 cm−3 occurs about 65 ns after formation of the discharge current, which is ideal for laser wakefield acceleration experiments reported by Karsch et al. [New J. Phys. 9, 415 (2007)].
Solving the accelerator-condenser coupling problem in a nanosecond dynamic transmission electron microscope
Authors: Reed B. W. , LaGrange T. , Shuttlesworth R. M. , Gibson D. J. , Campbell G. H. , Browning N. D.
Published: May 2010

We describe a modification to a transmission electron microscope (TEM) that allows it to briefly (using a pulsed-laser-driven photocathode) operate at currents in excess of 10 mA while keeping the effects of condenser lens aberrations to a minimum. This modification allows real-space imaging of material microstructure with a resolution of order 10 nm over regions several μm across with an exposure time of 15 ns. This is more than six orders of magnitude faster than typical video-rate TEM imaging. The key is the addition of a weak magnetic lens to couple the large-diameter high-current beam exiting the accelerator into the acceptance aperture of a conventional TEM condenser lens system. We show that the performance of the system is essentially consistent with models derived from ray tracing and finite element simulations. The instrument can also be operated as a conventional TEM by using the electron gun in a thermionic mode. The modification enables very high electron current densities in μm-sized areas and could also be used in a nonpulsed system for high-throughput imaging and analytical TEM.
Thermal breakage and self-healing of a polymer chain under tensile stress
Authors: Ghosh A. , Dimitrov D. I. , Rostiashvili V. G. , Milchev A. , Vilgis T. A.
Published: May 2010

We consider the thermal breakage of a tethered polymer chain of discrete segments coupled by Morse potentials under constant tensile stress. The chain dynamics at the onset of fracture is studied analytically by Kramers–Langer multidimensional theory and by extensive molecular dynamics simulations in one dimension (1D) and three dimension (3D) space. Comparison with simulation data in one and three dimensions demonstrates that the Kramers–Langer theory provides good qualitative description of the process of bond scission as caused by a collective unstable mode. We derive distributions of the probability for scission over the successive bonds along the chain which reveal the influence of chain ends on rupture in good agreement with theory. The breakage time distribution of an individual bond is found to follow an exponential law as predicted by theory. Special attention is focused on the recombination (self-healing) of broken bonds. Theoretically derived expressions for the recombination time and distance distributions comply with MD observations and indicate that the energy barrier position crossing is not a good criterion for true rupture. It is shown that the fraction of self-healing bonds increases with rising temperature and friction.
Parabolic curves in Lie groups
Authors: Pauley Michael
Published: May 2010

To interpolate a sequence of points in Euclidean space, parabolic splines can be used. These are curves which are piecewise quadratic. To interpolate between points in a (semi-)Riemannian manifold, we could look for curves such that the second covariant derivative of the velocity is zero. We call such curves Jupp and Kent quadratics or JK-quadratics because they are a special case of the cubic curves advocated by Jupp and Kent. When the manifold is a Lie group with bi-invariant metric, we can relate JK-quadratics to null Lie quadratics which arise from another interpolation problem. We solve JK-quadratics in the Lie groups SO(3) and SO(1,2) and in the sphere and hyperbolic plane, by relating them to the differential equation for a quantum harmonic oscillator.
Expanded chain dimensions in polymer melts with nanoparticle fillers
Authors: Frischknecht Amalie L. , McGarrity Erin S. , Mackay Michael E.
Published: May 2010

We apply the self-consistent polymer reference interaction site model (SC/PRISM) to liquid state calculations of the chain dimensions in polymer melts with added nanoparticle fillers. The nanoparticles are assumed to be smaller than the polymer radius of gyration and are attracted to the polymer so that they are miscible. We find that the nanoparticles perturb the chain dimensions, causing an increase in the radius of gyration with increasing nanoparticle volume fractions, assuming reasonable interaction energies between the various components. The magnitude of the expansion is in qualitative agreement with recent neutron scattering results and suggests that the SC/PRISM approach is reasonable when dealing with these apparent nonlinear phenomena present in nanocomposites in the protein limit.
A symmetry-breaking electromechanical detector
Authors: Mahboob I. , Froitier C. , Yamaguchi H.
Published: May 2010

The dynamical double well potential underpinning the stable oscillation phases in an electromechanical parametric resonator is manipulated via a secondary field excitation applied at the natural frequency of the oscillator. This enables symmetry to be lifted in the dynamical potential well and results in the parametric resonator oscillating with a preferred phase. The ability to break symmetry in the dynamical double well potential permits the realization of a symmetry-breaking detector which can resolve resonance frequency (f0) shifts of δf0/f0∼10−7 in a single-shot measurement.
Instrumentation for the in situ control of carrier recombination characteristics during irradiation by protons
Authors: Gaubas E. , Uleckas A. , Vaitkus J. , Raisanen J. , Tikkanen P.
Published: May 2010

Instrument and methods for the remote and in situ control of carrier recombination parameters during irradiation by protons of energy in the range of 3–8 MeV are presented. Direct techniques for measurements and separation of carrier recombination and trapping/generation characteristics based on the analysis of microwave probed photoconductivity transients during exposure on protons of different energies and irradiations at different temperatures are described. Simultaneously, a spectroscopy of activation energy of dominant traps has been performed before and just after irradiation by temperature scans of variation in the recombination parameters.
Metal-insulator transition in ZnO nanopowder during thermal cycling by impedance spectroscopy
Authors: Nadeem M. , Farooq Amina , Shin T. J.
Published: May 2010

We have investigated the electrical response on the pellet of ZnO nanopowder by impedance spectroscopy. Different trends of impedance plane plots have been discussed due to the modulations of relaxation time with temperatures. Thermal cycling induces irreversible changes in the resistance of the material which has been explained by incorporating the role of extended defects like oxidation of Zn interstitials at surfaces and intrinsic/extrinsic grain boundaries. Metal-insulator transition has been reported and discussed in term of combined effects of Zn interstitials and oxygen vacancies. Irreversible increase in the values of dielectric constant have been conferred with thermal cycling’s.
Storing light in active optical waveguides with single-negative materials
Authors: Lu W. T. , Huang Y. J. , Casse B. D. F. , Banyal R. K. , Sridhar S.
Published: May 2010

We show that a nonresonant planar waveguide consisting of conventional dielectric cladded with single-negative materials supports degenerate propagating modes for which the group velocity and total energy flow can be zero if the media are lossless. Absorptive losses will destroy the zero-group velocity condition for real frequency/complex wave vector modes. We show that by incorporating gain G into the core dielectric, there exists a critical gain value Gc at which we can recover the condition of zero group velocity, so that light pulses can be stopped and stored. This structure is simpler to achieve than double-negative metamaterials, has small footprint, and can be incorporated into ultracompact on-chip optoelectronics.
Pulse width narrowing due to dual ground state emission in quantum dot passively mode locked lasers
Authors: Mesaritakis Charis , Simos Christos , Simos Hercules , Mikroulis Spiros , Krestnikov Igor , Syvridis Dimitris
Published: May 2010

We present an experimental investigation of the emission properties of a multisection InGaAs quantum dot passively mode locked laser under dual waveband emission from the ground state (GS). A mode locking regime directly related to the GS splitting has been depicted. It is related to significant pulse width decrease with increasing injection current under dual peak emission from the GS, leading to generation of pulses with increased peak power with respect to the usual device operation.
Pretilt angle control and multidomain alignment of liquid crystals by using polyimide mixed with liquid crystalline prepolymer
Authors: Kim Ki-Han , Baek Jong-In , Cheong Byoung-Ho , Choi Hwan-Young , Shin Sung Tae , Kim Jae Chang , Yoon Tae-Hoon
Published: May 2010

We propose a method to control the pretilt angle of liquid crystals by employing a mixture of the vertical alignment polyimide and the liquid crystalline prepolymer (LCP). The pretilt angle between 10° and 90° can be controlled continuously by changing the mixing ratio of the LCP. Multidomains with different pretilt angles can be formed because the pretilt angle between 50° and 90° can be obtained by varying the UV exposure time region by region under a fixed mixing ratio. We confirmed experimentally that proposed alignment layers are thermally stable.
Thermophysical property-related comparison criteria for nanofluid heat transfer enhancement in turbulent flow
Authors: Yu W. , France D. M. , Timofeeva E. V. , Singh D. , Routbort J. L.
Published: May 2010

Heat transfer enhancement criteria for nanofluids over their base fluids are presented based on three separate considerations: Reynolds number, flow velocity, and pumping power. Analyses presented show that, among the three comparisons, the constant pumping power comparison is the most unambiguous; the constant flow velocity comparison can be quite reasonable under certain conditions but the constant Reynolds number comparison (the most commonly used in the engineering literature for nanofluids) distorts the physical situation, and therefore, should not be used.
Surface transfer hole doping of epitaxial graphene using MoO3 thin film
Authors: Chen Zhenyu , Santoso Iman , Wang Rui , Xie Lan Fei , Mao Hong Ying , Huang Han , Wang Yu Zhan , Gao Xing Yu , Chen Zhi Kuan , Ma Dongge , Wee Andrew Thye Shen , Chen Wei
Published: May 2010

Synchrotron-based in situ photoelectron spectroscopy investigations demonstrate effective surface transfer p-type doping of epitaxial graphene (EG) thermally grown on 4H–SiC(0001) via the deposition of MoO3 thin film on top. The large work function difference between EG and MoO3 facilitates electron transfer from EG to the MoO3 thin film. This leads to hole accumulation in the EG layer with an areal hole density of about 1.0×1013 cm−2, and places the Fermi level 0.38 eV below the graphene Dirac point.
Evaluated Kinetic Data for Combustion Modeling. Supplement I
Authors: Baulch D. L. , Cobos C. J. , Cox R. A. , Frank P. , Hayman G. , Just Th. , Kerr J. A. , Murrells T. , Pilling M. J. , Troe J. , Walker R. W. , Warnatz J.
Published: May 2010

This compilation updates and expands a previous evaluation of kinetic data on elementary, homogeneous, gas phase reactions of neutral species involved in combustion systems [J. Phys. Chem. Ref. Data 21, 411 (1992)]. The work has been carried out under the auspices of the European Community Energy Research and Development Program. Data sheets are presented for some 78 reactions and two tables in which preferred rate parameters are presented for reactions of ethyl, i-propyl, t-butyl, and allyl radicals are given. Each data sheet sets our relevant thermodynamic data, experimental kinetic data, references, and recommended rate parameters with their error limits. A table summarizing the recommended rate data is also given. The new reactions fall into two categories: first, to expand the previous compilation relating largely to the combustion in air of methane, ethane and aromatic compounds; and second, provide data for some of the key radicals involved in the combustion of higher alkanes.
Actor Networks, Modes of Production, and Waste Regimes: Reassembling the Macro-Social
Authors: Gille Zsuzsa
Published: May 2010

The author argues for the necessity of a macro-theoretical framework for a systematic understanding of the waste–society relationship—a synthesis of the Marxist mode of production concept and the posthumanist concept of actor networks, sociomaterial assemblages, or collectives. Based on empirical data on Hungary's socialist and capitalist waste history (1948 to the present), it is shown that macro dynamics are qualitatively different from micro ones and thus their analytical separation is retained. At the same time, it is demonstrated that the common fallacy of Marxist and posthumanist theories to conflate social scale with level of abstraction unduly demonized macro-level concepts. Finally it is shown that existing syntheses of Marxism and actor-network theory cannot but treat waste as a theoretical derivative of the concept of value, and thus elide waste's concrete materiality. The concept of waste regime is proposed to resolve these shortcomings.
A Governmental Contest: Regulating US Cinema during the Progressive Era
Authors: Olund Eric
Published: May 2010

Cinema was one of the hallmarks of early-20th-century urban life in the US, and it was quickly seen as symptomatic of a ‘crisis of governmentality’ faced by a rapidly changing society. Urban reformers debated how best to regulate it, but this was not only a debate over the unprecedented agency of the moving image itself. It was also a debate over how to understand the specific relations that constituted the ‘vulnerable and impressionable’ spectators who were the special concern of social reform and which underlay the more generic categories of population in reformist discourse. Also problematized was the precise relationship between spectators, the image, and the conditions of exhibition. While the problematization of cinema has largely been seen as a national phenomenon, in fact it had a geography that varied by scale and location and was constituted through local differences in population and governmental strategies.
Revealing differences in gene network inference algorithms on the network level by ensemble methods
Authors: Altay Gökmen , Emmert-Streib Frank
Published: May 2010

Motivation: The inference of regulatory networks from large-scale expression data holds great promise because of the potentially causal interpretation of these networks. However, due to the difficulty to establish reliable methods based on observational data there is so far only incomplete knowledge about possibilities and limitations of such inference methods in this context.

Results: In this article, we conduct a statistical analysis investigating differences and similarities of four network inference algorithms, ARACNE, CLR, MRNET and RN, with respect to local network-based measures. We employ ensemble methods allowing to assess the inferability down to the level of individual edges. Our analysis reveals the bias of these inference methods with respect to the inference of various network components and, hence, provides guidance in the interpretation of inferred regulatory networks from expression data. Further, as application we predict the total number of regulatory interactions in human B cells and hypothesize about the role of Myc and its targets regarding molecular information processing.

Contact:  v@bio-complexity.com

Supplementary information:  Supplementary data are available at Bioinformatics online.
Intermittent claudication as a predictor of outcome in patients with ischaemic systolic heart failure: analysis of the Controlled Rosuvastatin Multinational Trial in Heart Failure trial (CORONA)
Authors: Inglis Sally C. , McMurray John J.V. , Böhm Michael , Schaufelberger Maria , van Veldhuisen Dirk J. , Lindberg Magnus , Dunselman Peter , Hjalmarson Åke , Kjekshus John , Waagstein Finn , Wedel Hans , Wikstrand John ,   on behalf of the CORONA Study Group
Published: May 2010

Aims

To examine the relationship between baseline intermittent claudication and outcomes in patients enrolled in the Controlled Rosuvastatin Multinational Trial in Heart Failure trial (CORONA). Intermittent claudication is an independent predictor of worse outcome in coronary heart disease, but its prognostic importance in heart failure (HF) is unknown. Patients aged ≥60 years with NYHA class II‐IV, low ejection fraction HF of ischaemic aetiology were enrolled in CORONA. Rosuvastatin did not reduce the primary outcome or all‐cause mortality.

Methods and results

To determine whether intermittent claudication was an independent predictor of clinical outcomes, a three‐step multivariable model was built: (i) demographic/clinical variables, (ii) biochemical measures added, (iii) high‐sensitivity C‐reactive protein and N‐terminal pro B‐type natriuretic‐peptide added. Of the 5011 patients, 637 (12.7%) had intermittent claudication at baseline. Patients with intermittent claudication were more likely to be male (83 vs. 75%), be a current smoker (19 vs. 9%), and have diabetes mellitus (36 vs. 29%) relative to those without intermittent claudication. Over a median 33‐month follow‐up, 2168 patients died or were hospitalized for HF. Patients with intermittent claudication had an increased risk of death (any cause) (adjusted hazard ratio 1.36, 95% CI 1.19–1.56, P < 0.0001), death from worsening HF (1.35, 1.03–1.77, P = 0.028), sudden death (1.24, 1.00–1.54, P = 0.05), and risk of non‐fatal or fatal myocardial infarction (time to first event 1.67, 1.24–2.27, P < 0.001). In the full multivariable model, intermittent claudication remained an independent predictor of most outcomes evaluated.

Conclusion

Intermittent claudication is a relatively common symptom in ischaemic HF and an independent predictor of worse outcome.

Clinical Trial Registration Information: NCT00206310—http://clinicaltrials.gov/ct2/show/NCT00206310?term=corona&rank=2.
Impact of a climate regime shift on the migration of Japanese common squid (Todarodes pacificus) in the Sea of Japan
Authors: Kidokoro Hideaki , Goto Tsuneo , Nagasawa Toru , Nishida Hiroshi , Akamine Tatsuro , Sakurai Yasunori
Published: May 2010

Kidokoro, H., Goto, T., Nagasawa, T., Nishida, H., Akamine, T., and Sakurai, Y. 2010. Impact of a climate regime shift on the migration of Japanese common squid (Todarodes pacificus) in the Sea of Japan. – ICES Journal of Marine Science, 67: 1314–1322. Following a climate regime shift (RS) in 1989 in the northwest Pacific and Sea of Japan, the main spawning grounds of the Japanese common squid (Todarodes pacificus) shifted from inshore areas off Honshu Island to the Tsushima Strait, and the stock size increased. Migration patterns of T. pacificus occurred after the RS, based on tagging experiments conducted in July to September of 1984 and 1987–1991, are examined using monthly shifts in average latitude of recapture sites every 10 d. Before the RS, recaptures were in the central Sea of Japan and in inshore areas off Honshu Island, but after the RS, there were no recaptures inshore off Honshu Island. The average latitude of the recapture sites in September was about 36–37°N before the RS and north of 40°N (near the release sites) after the RS. It is likely that the location of the spawning grounds has changed.
TheArabidopsisNitrate Transporter NRT1.8 Functions in Nitrate Removal from the Xylem Sap and Mediates Cadmium Tolerance
Authors: Li Jian-Yong , Fu Yan-Lei , Pike Sharon M. , Bao Juan , Tian Wang , Zhang Yu , Chen Chun-Zhu , Zhang Yi , Li Hong-Mei , Huang Jing , Li Le-Gong , Schroeder Julian I. , Gassmann Walter , Gong Ji-Ming
Published: May 2010

Long-distance transport of nitrate requires xylem loading and unloading, a successive process that determines nitrate distribution and subsequent assimilation efficiency. Here, we report the functional characterization of NRT1.8, a member of the nitrate transporter (NRT1) family in Arabidopsis thaliana. NRT1.8 is upregulated by nitrate. Histochemical analysis using promoter-β-glucuronidase fusions, as well as in situ hybridization, showed that NRT1.8 is expressed predominantly in xylem parenchyma cells within the vasculature. Transient expression of the NRT1.8:enhanced green fluorescent protein fusion in onion epidermal cells and Arabidopsis protoplasts indicated that NRT1.8 is plasma membrane localized. Electrophysiological and nitrate uptake analyses using Xenopus  laevis oocytes showed that NRT1.8 mediates low-affinity nitrate uptake. Functional disruption of NRT1.8 significantly increased the nitrate concentration in xylem sap. These data together suggest that NRT1.8 functions to remove nitrate from xylem vessels. Interestingly, NRT1.8 was the only nitrate assimilatory pathway gene that was strongly upregulated by cadmium (Cd2+) stress in roots, and the nrt1.8-1 mutant showed a nitrate-dependent Cd2+-sensitive phenotype. Further analyses showed that Cd2+ stress increases the proportion of nitrate allocated to wild-type roots compared with the nrt1.8-1 mutant. These data suggest that NRT1.8-regulated nitrate distribution plays an important role in Cd2+ tolerance.
Identification of the 2-Hydroxyglutarate and Isovaleryl-CoA Dehydrogenases as Alternative Electron Donors Linking Lysine Catabolism to the Electron Transport Chain ofArabidopsisMitochondria
Authors: Araújo Wagner L. , Ishizaki Kimitsune , Nunes-Nesi Adriano , Larson Tony R. , Tohge Takayuki , Krahnert Ina , Witt Sandra , Obata Toshihiro , Schauer Nicolas , Graham Ian A. , Leaver Christopher J. , Fernie Alisdair R.
Published: May 2010

The process of dark-induced senescence in plants is relatively poorly understood, but a functional electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase (ETF/ETFQO) complex, which supports respiration during carbon starvation, has recently been identified. Here, we studied the responses of Arabidopsis thaliana mutants deficient in the expression of isovaleryl-CoA dehydrogenase and 2-hydroxyglutarate dehydrogenase to extended darkness and other environmental stresses. Evaluations of the mutant phenotypes following carbon starvation induced by extended darkness identify similarities to those exhibited by mutants of the ETF/ETFQO complex. Metabolic profiling and isotope tracer experimentation revealed that isovaleryl-CoA dehydrogenase is involved in degradation of the branched-chain amino acids, phytol, and Lys, while 2-hydroxyglutarate dehydrogenase is involved exclusively in Lys degradation. These results suggest that isovaleryl-CoA dehydrogenase is the more critical for alternative respiration and that a series of enzymes, including 2-hydroxyglutarate dehydrogenase, plays a role in Lys degradation. Both physiological and metabolic phenotypes of the isovaleryl-CoA dehydrogenase and 2-hydroxyglutarate dehydrogenase mutants were not as severe as those observed for mutants of the ETF/ETFQO complex, indicating some functional redundancy of the enzymes within the process. Our results aid in the elucidation of the pathway of plant Lys catabolism and demonstrate that both isovaleryl-CoA dehydrogenase and 2-hydroxyglutarate dehydrogenase act as electron donors to the ubiquinol pool via an ETF/ETFQO-mediated route.
Ulcerating stasis dermatitis of the forearm due to arteriovenous fistula: A case report and review of the published work
Authors: DEGUCHI Emi , IMAFUKU Shinichi , NAKAYAMA Juichiro
Published: May 2010

Stasis ulcers of the upper limbs are rare, and only 30 cases have been reported, all of which were due to rheological abnormalities. A 59‐year‐old woman sustained an injury to her right upper limb, resulting in incomplete transections of the brachial artery and the brachial vein. Emergent reconstruction of the brachial artery was performed. Raynaud’s phenomenon was observed postoperatively, followed by extreme edema, eczematization and the development of ulcers on the forearm. She was referred to our hospital for treatment. 3‐D computed tomography (CT) revealed end‐to‐end anastomosis of the brachial artery and the brachial vein. An additional brachial–radial artery bypass and closure of the anastomosis dramatically improved her skin symptoms. Vascular anomalies including surgery should be suspected when patients present with stasis dermatitis of the upper limbs.