bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biophysical and enzymatic properties of the simian and prototype foamy virus reverse transcriptases
Authors: Hartl Maximilian J , Mayr Florian , Rethwilm Axel , Wöhrl Birgitta M 
Published: January 2010

Abstract

Background
The foamy virus Pol protein is translated independently from Gag using a separate mRNA. Thus, in contrast to orthoretroviruses no Gag-Pol precursor protein is synthesized. Only the integrase domain is cleaved off from Pol resulting in a mature reverse transcriptase harboring the protease domain at the N-terminus (PR-RT). Although the homology between the PR-RTs from simian foamy virus from macaques (SFVmac) and the prototype foamy virus (PFV), probably originating from chimpanzee, exceeds 90%, several differences in the biophysical and biochemical properties of the two enzymes have been reported (i.e. SFVmac develops resistance to the nucleoside inhibitor azidothymidine (AZT) whereas PFV remains AZT sensitive even if the resistance mutations from SFVmac PR-RT are introduced into the PFV PR-RT gene). Moreover, contradictory data on the monomer/dimer status of the foamy virus protease have been published.

Results
We set out to purify and directly compare the monomer/dimer status and the enzymatic behavior of the two wild type PR-RT enzymes from SFVmac and PFV in order to get a better understanding of the protein and enzyme functions. We determined kinetic parameters for the two enzymes, and we show that PFV PR-RT is also a monomeric protein.

Conclusions
Our data show that the PR-RTs from SFV and PFV are monomeric proteins with similar biochemical and biophysical properties that are in some aspects comparable with MLV RT, but differ from those of HIV-1 RT. These differences might be due to the different conditions the viruses are confronted with in dividing and non-dividing cells.
A proinsulin74-90-derived protease-resistant, altered peptide ligand increases TGF-β1 secretion in PBMC from patients with type 1 diabetes mellitus
Authors: van Aalst Denise , Kalbacher Hubert , Palesch David , Zou Fang , Spyrantis Andreas , Rosinger Silke , Boehm Bernhard O , Burster Timo 
Published: January 2010

Abstract
Proinsulin-based protease-resistant altered peptide ligands modulate proinsulin-reactive T cells to secret the anti-inflammatory cytokine TGF-β1.
Proinsulin is a major diabetes-associated autoantigen. APL have been shown to manipulate the immune response of T cells. Here, we generated a lysosomal protease-resistant proinsulin74–90-derived APL using a CS-directed amino acid modification approach. These prAPL activated TGF-β1 secretion in proinsulin-reactive T cells from PBMC of patients with T1D. We provide evidence that proinsulin-derived prAPL modulate the cytokine signature of proinsulin-reactive T cells at a micromolar range by increasing anti-inflammatory cytokines, including TGF-β1. Thus, the use of prAPL is a promising tool to mitigate autoaggressive T cells.
Acute antipsychotic-induced akathisia revisited
Authors: Poyurovsky Michael 
Published: January 2010

SummaryAkathisia remains one of the most prevalent and distressful
antipsychotic-induced adverse events. Effective and well-tolerated treatment
is a major unmet need in akathisia that merits a search for new remedies.
Accumulating evidence indicates that agents with marked serotonin-2A
receptor antagonism may represent a new class of potential anti-akathisia
treatment.
Religion, spirituality and mental health
Authors: Dein Simon , Cook Christopher C. H. , Powell Andrew , Eagger Sarah 
Published: January 2010

SummaryResearch demonstrates important associations between religiosity and well-being; spirituality and religious faith are important coping mechanisms for managing stressful life events. Despite this, there is a religiosity gap between mental health clinicians and their patients. The former are less likely to be religious, and recent correspondence in the Psychiatric Bulletin suggests that some at least do not consider it appropriate to encourage discussion of any spiritual or religious concerns with patients. However, it is difficult to see how failure to discuss such matters can be consistent with the objective of gaining a full understanding of the patient's condition and their self-understanding, or attracting their full and active engagement with services.
Chewing variation in lepidosaurs and primates
Authors: Ross C. F. , Baden A. L. , Georgi J. , Herrel A. , Metzger K. A. , Reed D. A. , Schaerlaeken V. , Wolff M. S. 
Published: January 2010

SUMMARYMammals chew more rhythmically than lepidosaurs. The research presented here evaluated possible reasons for this difference in relation to differences between lepidosaurs and mammals in sensorimotor systems. Variance in the absolute and relative durations of the phases of the gape cycle was calculated from kinematic data from four species of primates and eight species of lepidosaurs. The primates exhibit less variance in the duration of the gape cycle than in the durations of the four phases making up the gape cycle. This suggests that increases in the durations of some gape cycle phases are accompanied by decreases in others. Similar effects are much less pronounced in the lepidosaurs. In addition, the primates show isometric changes in gape cycle phase durations, i.e. the relative durations of the phases of the gape cycle change little with increasing cycle time. In contrast, in the lepidosaurs variance in total gape cycle duration is associated with increases in the proportion of the cycle made up by the slow open phase. We hypothesize that in mammals the central nervous system includes a representation of the optimal chew cycle duration maintained using afferent feedback about the ongoing state of the chew cycle. The differences between lepidosaurs and primates do not lie in the nature of the sensory information collected and its feedback to the feeding system, but rather the processing of that information by the CNS and its use feed-forward for modulating jaw movements and gape cycle phase durations during chewing.
Distinct startle responses are associated with neuroanatomical differences in pufferfishes
Authors: Greenwood A. K. , Peichel C. L. , Zottoli S. J. 
Published: January 2010

SUMMARYDespite the key function of the Mauthner cells (M-cells) in initiating escape responses and thereby promoting survival, there are multiple examples of M-cell loss across the teleost phylogeny. Only a few studies have directly considered the behavioral consequences of naturally occurring M-cell variation across species. We chose to examine this issue in pufferfishes, as previous research suggested that there might be variability in M-cell anatomy in this group of fish. We characterized the M-cell anatomy and fast-start responses of two pufferfish species, Tetraodon nigroviridis and Diodon holocanthus. T. nigroviridis showed robust fast-starts to both tactile and acoustic startling stimuli. These fast-starts occurred with a latency typical of M-cell initiation in other fish, and retrograde labeling of spinal-projection neurons revealed that T. nigroviridis does have M-cells. By contrast, D. holocanthus only rarely exhibited fast-start-like behavior, and these responses were at a substantially longer latency and were much less extensive than those of T. nigroviridis. Using three complementary anatomical techniques we were unable to identify obvious M-cell candidates in D. holocanthus. These results provide a clear correlation between M-cell presence or absence and dramatic differences in fast-start behavior. The rich diversity within the pufferfish clade should allow future studies investigating the factors that contribute to this correlated anatomical and behavioral variation.
Making sense of electrical sense in crayfish
Authors: Patullo B. W. , Macmillan D. L. 
Published: January 2010

SUMMARY
The five sensory modalities of humans are also found in a wide range of invertebrates. Other vertebrates have evolved additional special senses, such as the magnetic sense, which are also found in some invertebrates. However, there remain a few sensory abilities that curiously appear to be found in either vertebrates or invertebrates, but not both. For example, electrosensitivity — the ability to detect electric fields in water — which should benefit vertebrates and invertebrates alike, is apparently only used by vertebrates. However, recent reports suggest that some invertebrates could have an electric sense. Here we examine that possibility further and demonstrate a behavioural threshold to low-level electrical fields in two freshwater invertebrates. The responses are not low enough for them to detect the Earth's magnetic field as some other electroreceptive species can do, but sufficiently low for them to use in navigation or prey and predator detection. This finding challenges the current view of the sensory world of aquatic invertebrates and has implications for the evolution of this ability.
Mounting of erratic histoincompatible responses in hermatypic corals: a multi-year interval comparison
Authors: Amar K.-O. , Rinkevich B. 
Published: January 2010

SUMMARY
Studies on allorecognition in the phylum Cnidaria have disclosed complex arrays of effector mechanisms, specificity and competency to distinguish precisely between self and non-self attributes, and have revealed the existence of allogeneic maturity. Here we studied allo-responses between young Stylophora pistillata colonies by following 517 allogeneic interactions between naturally settled kin aggregates and by establishing 417 forced allogeneic and autogeneic assays made of solitarily settled spat that were cut into two similar size subclones, of which one had been challenged allogeneically. Fused assays were exposed to a second allorecognition challenge, made of three allogeneic types. Whereas about half of the kin allogeneic interactions led to tissue fusions and chimera formations, none of the 83 non-sibling pair combinations were histocompatible. In contrast to previous results we recorded rejections between siblings at the age of less than two months. More challenging, we documented cases of fusions between interacting siblings at ages older than one-year-old partners, all differing from a previous study made on the same coral population more than a decade ago. Similar erratic histoincompatible responses were recorded in other pocilloporid species. We suggest that these results reflect reduced genetic heterogeneity caused by chronic anthropogenic impacts on shallow water coral populations where planulae originating from the same mother colony or from different mother colonies that are genetically related share increasing parts of their genomes. Offspring born to related parents may also reveal an increase in genomic homozygosity, and altogether impose erratic alloimmunity.
Endovenous treatments for varicose veins – over-taking or over-rated?
Authors: Shepherd A C , Gohel M S , Hamish M , Lim C S , Davies A H 
Published: January 2010

Objectives A variety of endovenous therapies for the treatment of superficial venous incompetence are currently available. The aim of this study was to evaluate the prevalence of endovenous techniques used by consultant vascular surgeons in the United Kingdom. Methods An anonymous online survey of 16 multiple choice questions relating to the nature and provision of treatment for varicose veins was devised. Consultant members of the Vascular Society of Great Britain and Ireland were invited to participate by email. Results A total of 108/352 (31%) surgeons completed the survey. The majority offered surgery as the first-line treatment for primary great saphenous vein (GSV) and small saphenous vein (SSV) incompetence (69% and 74%, respectively). Endovenous procedures were offered as first-line treatment by 32/108 (29.6%) for GSV reflux, 36/51 (70.6%) surgeons performed these under local anaesthetic and 21/51 (41.2%) were performed as an outpatient procedure. The most important factor influencing treatment decisions was considered to be patient preference by 77/108 (71.3%) surgeons, although 48/61 (78.7%) respondents were restricted by primary care trusts with regard to endovenous treatments, and 33/108 (30.6%) offered different treatments to private patients. Conclusion Traditional surgery remains the most commonly offered treatment for patients with varicose veins. The provision of endovenous therapies varies greatly, and there are significant differences in local availability regarding these treatments.
Study on Organic Triplet Exciton Emission and Quenching
Processes by Low-temperature Photo- and Electroluminescence
Spectroscopy
Authors: Kaufmann Nils Asmus Kristian , Jessen Frank , Heuken M. , Boerner Herbert , Kalisch Holger , Jansen R. H. 
Published: January 2010

AbstractOrganic light emitting diodes (OLED) are efficient light sources based on
organic semiconductors. Unlike inorganic LEDs which are more or less point
sources, OLED are planar light sources with up to 1 m2 in area.
By using organic materials, they are cheap to produce and economical to use.
The determination of triplet exciton energy levels is of interest for the
development of efficient OLED, based on the fact that electrical excitation
usually creates three times as many triplets as singlets. Additionally, the
knowledge of these energy levels is crucial for the design and choice of
emitter matrix materials and exciton blocking layers. These values are
normally determined by photoluminescence (PL) measurements in solution for
materials which show intersystem crossing (ISC) between singlet and triplet
states. For some materials, the triplet levels cannot be measured this way
because some materials prohibit ISC. In this work, a method is presented
which allows the determination of the energy levels using low-temperature
electroluminescence (EL) spectroscopy. The dependence on ISC is avoided by
creating triplets directly with electrical excitation and this allows to
measure a large class of organic materials. A low-temperature EL spectrum is
presented for
N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD) in
a 3-phenyl-4-(1‘-naphthyl)-5-phenyl-1,2,4-triazole (TAZ) matrix (TPD/TAZ
1:3) at 77 K. Triplet emission is only observed at very low charge carrier
density (0.5 μA/mm2). Quenching processes are analyzed using
combined EL and PL measurements and unipolar devices. Two factors can be the
cause of the quenching: A strong quenching based on a low concentration of
electrically activated impurities could explain the dependency. The other
explanation points to a quenching based on electrons in the emitting layer.
This might be explained with triplet-polaron quenching (TPQ). TPQ is
proportional to the charge carrier density and contributes the dominant part
to the quenching at low current densities.
Effects of annealing on donor and acceptor concentrations in Ga-doped ZnO thin films
Authors: Look David C. , Ghosh Kartik , Leedy Kevin 
Published: January 2010

AbstractTemperature-dependent Hall-effect measurements have been performed on three Ga-doped ZnO thin films of various thicknesses (65, 177, and 283 nm), grown by pulsed laser deposition at 400 °C and annealed at 400 °C for 10 min in Ar, N2, or forming-gas (5% H2 in Ar). The donor ND and acceptor NAconcentrations as a function of sample thickness and annealing conditions are determined by a new formalism that involves only ionized-impurity and boundary scattering. Before annealing, the samples are highly compensated, with ND = (2.8 ± 0.3) × 1020 cm-3 and NA = (2.6 ± 0.2) × 1020 cm-3. After annealing in Ar the samples are less compensated, with ND = (3.7 ± 0.1) × 1020 cm-3 and NA = (2.0 ± 0.1) × 1020 cm-3; furthermore, these quantities are nearly independent of thickness. However, after annealing in N2 and forming-gas, ND and NA are thickness dependent, partly due to depth-dependent diffusion of N2 and H, respectively.
Light beam induced current measurements on ZnO Schottky diodes and MESFETs
Authors: von Wenckstern Holger , Zhang Zhipeng P. , Lorenz Michael , Czekalla Christian , Frenzel Heiko , Lajn Alexander , Grundmann Marius 
Published: January 2010

AbstractThe homogeneity of the Schottky barrier potential of reactively sputtered PdOy/ZnO Schottky contacts has been investigated by light beam-induced current measurements on the micrometer scale. It is found that a metallic capping layer, acting as an equipotential surface, is not necessary for PdOy/ZnO Schottky contacts in contrast to AgxO/ZnO Schottky diodes. Further, we probed the generated photocurrent of a ZnO-based metal-semiconductor field-effect transistor for a closed and open channel, respectively. The photocurrent is, in general, one order of magnitude larger for closed channel conditions. The position of maximum photocurrent generation shifts towards the drain for higher source drain voltages for closed channel conditions, whereas it is nearly independent of the source drain potential for an open channel.
Studies of Ni and Co Doped Amorphous AlN for Magneto-optical Applications
Authors: Jadwisienczak Wojciech M. , Tanaka Hiroki , Kordesch Marty E. , Khan Aurangzeb , Kaya Savas , Vuppuluri Venkat 
Published: January 2010

AbstractMagneto-optical properties of Ni- and Co-doped amorphous AlN thin films were investigated as a function of post grown annealing temperature using magneto-optical Kerr effect (MOKE) spectroscopy. The x-ray diffraction spectra confirmed that the as-grown material is amorphous and retained its morphology after thermal treatment; however the sample morphology strongly depends on the concentration of incorporated transition metals. We observed with help of transmission electron microscopy and atomic force microscopy that the films surface containing TMs with concentrations larger than ∼10 at.% undergo morphological changes suggesting possible Ni and Co atom clustering. Significant enhancement of the polar Kerr rotation signal was observed for Ni- and Co-doped a-AlN materials annealed above 300 °C in nitrogen. The studied materials have shown strong magnetic isotropy in polar geometry whereas the MOKE measurements in longitudinal geometry did not show an explicit signal for the transition metals doped a-AlN studied.
Ion induced formation of Silicon nitride substrate and GaN overlayer growth at room temperature on Si (111) surface
Authors: Kumar Praveen , Kumar Mahesh , Gupta Govind , Mehta Bodh R. , Shivaprasad Sonanda M. 
Published: January 2010

AbstractGaN and related nitride semiconductors have attracted great attention in view of their wide applications in photonics and high temperature & high power electronic devices. Among other issues, reduction of defect densities by forming these interfaces at lower temperature and on novel substrates has been the motivation for several researchers. In the present study ion-induced conversion of Si (111) surface into silicon nitride at room temperature is optimized and used as substrate for the growth of Ga films. These Ga films are again nitrided by optimal N+ ion bombardment. Experiments have been performed in-situ in an ultra high vacuum chamber equipped with a Ga source and X-ray photoelectron spectrometer (XPS) at base pressure of 2×10-10 torr. The energy dependence of the nitridation is carefully performed at constant flux. The results clearly demonstrate the Si-N bond formation after a energy of 2 keV and the formation of GaN layer after 800eV of ion bombardment on Si (111) 7×7 surface and Ga adsorbed silicon nitride surface, respectively. The FWHM and chemical shifts in the core-level spectra of Si(2p), Ga(2p) and N(1s) have been analyzed to probe the interface reactions. The results demonstrate a possible novel and low temperature approach towards the integration of III-nitride & silicon technologies, since silicon nitride bonds can act as barriers to dislocation propagation.
Growth temperature - phase stability relation in In1-xGaxN epilayers grown by high-pressure CVD
Authors: Durkaya Goksel , Alevli Mustafa , Buegler Max , Atalay Ramazan , Gamage Sampath , Kaiser Martin , Kirste Ronny , Hoffmann Axel , Jamil Muhammad , Ferguson Ian , Dietz Nikolaus 
Published: January 2010

AbstractThe influence of the growth temperature on the phase stability and composition of single-phase In1-xGaxN epilayers has been studied. The In1-xGaxN epilayers were grown by high-pressure Chemical Vapor Deposition with nominally composition of x = 0.6 at a reactor pressure of 15 bar at various growth temperatures. The layers were analyzed by x-ray diffraction, optical transmission spectroscopy, atomic force microscopy, and Raman spectroscopy. The results showed that a growth temperature of 925°C led to the best single phase InGaN layers with the smoothest surface and smallest grain areas
Lattice Parameter Variation in ScGaN Alloy Thin Films on MgO(001) Grown by RF Plasma Molecular Beam Epitaxy
Authors: Constantin Costel , Jeongihm Pak , Wang Kangkang , Chinchore Abhijit , Meng Shi , Smith Arthur R. 
Published: January 2010

AbstractWe present the structural and surface characterization of the alloy formation of scandium gallium nitride ScxGa1-xN(001)/MgO(001) grown by radio-frequency molecular beam epitaxy over the Sc range of x = 0-100%. In-plane diffraction measurements show a clear face-centered cubic surface structure with single-crystalline epitaxial type of growth mode for all x; a diffuse/distinct transition in the surface structure occurs at near x = 0.5. This is consistent with out-of-plane diffraction measurements which show a linear variation of perpendicular lattice constant for x = 0 to 0.5, after which the out-of-plane lattice parameter becomes approximately constant. The x = 0.5 transition is interpreted as being related to the cross-over from zinc-blende to rock-salt structure.
GaN Photonic-Crystal Surface-Emitting Laser
Authors: Yoshimoto Susumu , Matsubara Hideki , Sakai Kyosuke , Noda Susumu 
Published: January 2010

AbstractWe introduce the lasing principle and important characteristics of photonic-crystal surface-emitting laser (PC-SELs). Specifically, we demonstrate two-dimensional coherent lasing oscillation with GaN PC-SELs, using a unique crystal growth technique called “air hole retained overgrowth” (AROG). Above the threshold, we obtained a two-dimensionally distributed near-field pattern, and a distinctive far-field pattern with a divergence angle less than 1°. We also investigate a suitable sample structure for the reduction of the threshold current, where the PC structure is moved from an n-cladding layer to a p-cladding one. This is an important step towards the realization of novel light sources that can be integrated two dimensionally for a variety of new scientific and engineering applications in the blue to ultraviolet wavelengths.
Superlattices from Diamond
Authors: Watanabe Hideyuki , Shikata S. 
Published: January 2010

AbstractDiamond superlattices were fabricated by producing multilayer structures of isotopically pure carbon-12 (12C) and carbon-13 (13C), which confine electrons by a difference in band-gap energy. Secondary ion mass spectrometry (SIMS) measurements were employed to characterize the isotopic composition of the diamond superlattices. Layers between 2 nm and 350 nm in thickness can be designed and fabricated using a microwave plasma-assisted chemical vapor deposition technique.