bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scale dependence of the variance anisotropy near the proton gyroradius scale: Additional evidence for kinetic Alfvén waves in the solar wind at 1 AU
Authors: Podesta John J. , TenBarge Jason M. 
Published: August 2012

The kinetic Alfvén wave (KAW) has the property that for βp ∼ 1 the ratio (δB∥)2/(δB⊥)2 approaches zero in the small wave number limit k⊥ρp ≪ 1 and increases monotonically to values of order unity when k⊥ρp ∼ 1, where ρp is the thermal proton gyroradius. In this study, the wave number dependence of the ratio (δB∥)2/(δB⊥)2 is used to investigate the existence of KAWs in the solar wind near the proton gyroradius scale k⊥ρp = 1. To facilitate comparisons between theory and observations, solar wind measurements of (δB∥)2/(δB⊥)2 are restricted to times when the local mean magnetic field B0 is nearly perpendicular to the local flow velocity of the solar wind V. The quantity (δB∥)2 is the average magnetic power in the B0 direction and (δB⊥)2 is the average magnetic power in the V × B0 direction. The analysis of 20 high speed streams in the ecliptic plane near 1 AU from 2007 through 2011 consistently yield quantitatively similar results which all show a steady increase in the ratio (δB∥)2/(δB⊥)2 in the neighborhood of k⊥ρp= 1 that is in reasonable agreement with the theory of KAWs derived from the Vlasov‐Maxwell dispersion relation. These results are interpreted as evidence for the existence of an axisymmetric spectrum of KAWs in the fast solar wind at wave numbers neark⊥ρp = 1 where the energy spectrum of solar wind fluctuations steepens and kinetic physics becomes important.
Guiding and focusing of a nanosecond infrared laser within transient hollow plasma femtosecond filament channels
Authors: Wen Sy-Bor , Chen Chien-Fen , Mao Xianglei , Russo Richard E 
Published: August 2012

Abstract
Long distance guidance and focusing of infrared (IR) nanosecond-pulsed laser light in a hollow plasma channel formed with femtosecond pulsed laser plasma filaments is examined with numerical experiments. Numerical models show that a thick hollow plasma channel can provide low loss long distance (>100 m) guidance of the IR nanosecond-pulsed laser beam. The effectiveness of guidance is determined by the electron number density, thickness of the plasma filament shell and the size of the inner radius of the hollow plasma channel. The hollow plasma channel can be thought of as an open-space optical fibre. The required thickness of the plasma channel with specified electron number density and the inner radius can be estimated with modal analysis, similar to that used for optical fibres. In addition, with a small tapering angle in the hollow plasma channel, the guided light can be moderately focused during long distance propagation. Owing to the rapid decay of electron number density of a plasma channel in free space, the delay time between the generation of the plasma channel and the guided light along with the duration of the guided light are better to be maintained within a few nanoseconds.
Characteristics of plume plasma and its effects on ablation depth during ultrashort laser ablation of copper in air
Authors: Hu Wenqian , Shin Yung C , King Galen 
Published: August 2012

Abstract
The characteristics of plume plasma induced by ultrashort laser ablation of copper in air are studied experimentally and theoretically in this paper. The plasma front evolutions are captured using a high-speed intensified charge-coupled device camera, while the plasma temperature and electron number density evolutions are obtained from the plasma emission spectra measured by a high-precision spectrometer. For the theoretical study, a hybrid simulation model is proposed to combine an atomistic model for the early stage and a hydrodynamic model for the later stage. The simulation model is validated against the measurement results and shown to be capable of predicting plasma properties for a broader range of fluence, without being constrained by the signal strength as in the measurements. Both experimental and theoretical results show that the nonlinear relationship between plasma properties and laser fluence directly relates to the relationship between ablation depth and laser fluence. Therefore, the measurable and predictable plasma properties reveal the underlying ablation mechanism that has been studied primarily by theory.
Direct growth of TiO2 nanotubes on transparent substrates and their resistive switching characteristics
Authors: Chu Dewei , Younis Adnan , Li Sean 
Published: August 2012

Abstract
In this work, TiO2 nanotubes were directly grown by one-step electrochemical deposition process, in the absence of any templates or metal Ti substrates. The Au/TiO2 nanotube/fluorine-doped tin oxide glass capacitor exhibits stable bipolar resistive switching behaviour. The resistive switching behaviour may be related to the oxygen vacancies, giving rise to the formation of straight and extensible conducting filaments along the wall of each vertically aligned TiO2 nanotube. Superior stability in resistive switching characteristics was also observed, indicating that TiO2 nanotubes are one of the potential materials for next-generation nonvolatile memory applications.
Lyα DOMINANCE OF THE CLASSICAL T TAURI FAR-ULTRAVIOLET RADIATION FIELD
Authors: Schindhelm Rebecca N. , France Kevin , Herczeg Gregory J. , Bergin Edwin , Yang Hao , Brown Alexander , Brown Joanna M. , Linsky Jeffrey L. , Valenti Jeff 
Published: August 2012

ABSTRACT
Far-ultraviolet (FUV) radiation plays an important role in determining chemical abundances in protoplanetary disks. H i Lyman α (Lyα) is suspected to be the dominant component of the FUV emission from Classical T Tauri Stars (CTTSs), but is difficult to measure directly due to circumstellar and interstellar H i absorption. To better characterize the intrinsic Lyα radiation, we present FUV spectra of 14 CTTSs taken with the Hubble Space Telescope Cosmic Origins Spectrograph and Space Telescope Imaging Spectrograph instruments. H2 fluorescence, commonly seen in the spectra of CTTSs, is excited by Lyα photons, providing an indirect measure of the Lyα flux incident upon the warm disk surface. We use observed H2 progression fluxes to reconstruct the CTTS Lyα profiles. The Lyα flux correlates with total measured FUV flux, in agreement with an accretion-related source of FUV emission. With a geometry-independent analysis, we confirm that in accreting T Tauri systems Lyα radiation dominates the FUV flux (∼1150 Å –1700 Å). In the systems surveyed this one line comprises 70%–90% of the total FUV flux.
IgGs containing light chains of the λ- and κ- type and of all subclasses (IgG1–IgG4) from the sera of patients with systemic lupus erythematosus hydrolyze myelin basic protein
Authors: Bezuglova Anna M. , Konenkova Ludmila P. , Buneva Valentina N. , Nevinsky Georgy A. 
Published: August 2012

AbstractHuman myelin basic protein (hMBP)-hydrolyzing activity was recently shown to be an intrinsic property of antibodies from systemic lupus erythematosus (SLE) patients. Here, we present the first evidence demonstrating a significant diversity of different fractions of polyclonal IgGs (pIgGs) from SLE patients in their affinity for hMBP and in the ability of pIgGs to hydrolyze hMBP at different optimal pH values (5.3–9.5); the pH profiles of IgG1, IgG2, IgG3 and IgG4 were unique. IgGs containing the λ-type of light chains demonstrated higher relative activities (RAs) in the hydrolysis of hMBP and its oligopeptides (OPs) than κ-IgGs. IgGs of all four subclasses were catalytically active; their RAs in the hydrolysis of hMBP increased in the following order: IgG4 &lt; IgG2 &lt; IgG3 &lt; IgG1. Metal-dependent proteolytic activity of λ-IgG, IgG1, IgG2 and IgG3 was higher than their serine protease-like activity, while these activities of κ-IgG were comparable. Phenylmethylsulfonylfluoride had almost no effect on the activity of IgG4, while EDTA significantly suppressed its activity. The RAs of λ-IgG in the hydrolysis of four OPs corresponding to different cleavage sites of hMBP were remarkably higher than those for κ-IgGs. IgG1–IgG4 demonstrated different RAs and patterns of hydrolysis of these four OPs. Although combination of Ca2+ plus Mg2+ was the best in the activation of IgG1 and IgG2, IgG3 and IgG4 demonstrated the highest activity in the presence of Ca2+ plus Co2+. The ratio of the RAs of λ-IgG, κ-IgG and IgG1–IgG4 preparations in all analyzed cases was individual for each preparation.
Two Novel RING-Type Ubiquitin Ligases, RGLG3 and RGLG4, Are Essential for Jasmonate-Mediated Responses in Arabidopsis
Authors: Zhang Xu , Wu Qian , Ren Jiao , Qian Wanqiang , He Shanping , Huang Kuowei , Yu XiangChun , Gao Yin , Huang Ping , An Chengcai 
Published: August 2012

Abstract
Jasmonates (JAs) regulate various stress responses and development processes in plants, and the JA pathway is tightly controlled. In this study, we report the functional characterization of two novel RING-type ubiquitin ligases, RING DOMAIN LIGASE3 (RGLG3) and RGLG4, in modulating JA signaling. Both RGLG3 and RGLG4 possessed ubiquitin ligase activities and were widely distributed in Arabidopsis (Arabidopsis thaliana) tissues. Altered expression of RGLG3 and RGLG4 affected methyl JA-inhibited root growth and JA-inductive gene expression, which could be suppressed by the coronatine insensitive1 (coi1) mutant. rglg3 rglg4 also attenuated the inhibitory effect of JA-isoleucine-mimicking coronatine on root elongation, and consistently, rglg3 rglg4 was resistant to the coronatine-secreting pathogen Pseudomonas syringae pv tomato DC3000, suggesting that RGLG3 and RGLG4 acted in response to the coronatine and promoted JA-mediated pathogen susceptibility. In addition, rglg3 rglg4 repressed wound-stunted plant growth, wound-stimulated expression of JA-responsive genes, and wound-induced JA biosynthesis, indicating their roles in JA-dependent wound response. Furthermore, both RGLG3 and RGLG4 responded to methyl JA, P. syringae pv tomato DC3000, and wounding in a COI1-dependent manner. Taken together, these results indicate that the ubiquitin ligases RGLG3 and RGLG4 are essential upstream modulators of JA signaling in response to various stimuli.
Overexpression of enhancer of zeste homolog 2 and MUC1 may be related to malignant behaviour in intraductal papillary neoplasm of the bile duct
Authors: Sasaki Motoko , Matsubara Takashi , Yoneda Norihide , Nomoto Kazuhiro , Tsuneyama Koichi , Sato Yasunori , Nakanuma Yasuni 
Published: August 2012

Aims:  Intraductal papillary neoplasm of the bile duct (IPNB) usually has a favourable prognosis, but occasionally is associated with invasive carcinoma. Overexpression of the polycomb group protein enhancer of zeste homolog 2 (EZH2) is involved in the progression of malignant tumours. In this study, we examined the significance of EZH2 expression in IPNB and its association with clinicopathological features and the expression of p16INK4a, p53 and mucin core proteins.Methods and results:  We examined immunohistochemically the expression of EZH2, p16INK4a, MUC mucin core proteins and p53 in 15 patients with IPNB without invasion, including the cystic variant [male/female ratio (M/F) = 9/6], and in 19 with IPNB associated with invasive carcinoma (M/F = 13/6). The expression levels of EZH2, p53 and MUC1 were significantly lower (P < 0.01), and of MUC6 were significantly higher (P < 0.05), in IPNB without invasion than in IPNB with invasion. Expression of EZH2 was significantly correlated with expression of MUC1 (P < 0.01) and inversely correlated with expression of MUC6 (P < 0.05). In cholangiocarcinoma cells (HuCTT‐1 and TFK‐1), knockdown of EZH2 and MUC1 by small interfering RNA decreased invasion and proliferation, whereas knockdown of MUC6 increased invasion.Conclusions:  Overexpression of EZH2 may be associated with malignant behaviour in IPNB in parallel with up‐regulated MUC1 expression and down‐regulated MUC6 expression.
Neuronally expressed Ras‐family GTPase Di‐Ras modulates synaptic activity in Caenorhabditis elegans
Authors: Tada Minoru , Gengyo‐Ando Keiko , Kobayashi Tetsuo , Fukuyama Masamitsu , Mitani Shohei , Kontani Kenji , Katada Toshiaki 
Published: August 2012

Ras‐family GTPases regulate a wide variety of cellular functions including cell growth and differentiation. Di‐Ras, which belongs to a distinct subfamily of Ras‐family GTPases, is expressed predominantly in brain, but the role of Di‐Ras in nervous systems remains totally unknown. Here, we report that the Caenorhabditis elegans Di‐Ras homologue drn‐1 is expressed specifically in neuronal cells and involved in synaptic function at neuromuscular junctions. Loss of function of drn‐1 conferred resistance to the acetylcholinesterase inhibitor aldicarb and partially suppressed the aldicarb‐hypersensitive phenotypes of heterotrimeric G‐protein mutants, in which acetylcholine release is up‐regulated. drn‐1 mutants displayed no apparent defects in the axonal distribution of the membrane‐bound second messenger diacylglycerol (DAG), which is a key stimulator of acetylcholine release. Finally, we have identified EPAC‐1, a C. elegans Epac homologue, as a binding partner for DRN‐1. Deletion mutants of epac‐1 displayed an aldicarb‐resistant phenotype as drn‐1 mutants. Genetic analysis of drn‐1 and epac‐1 showed that they acted in the same pathway to control acetylcholine release. Furthermore, DRN‐1 and EPAC‐1 were co‐immunoprecipitated. These findings suggest that DRN‐1 may function cooperatively with EPAC‐1 to modulate synaptic activity in C. elegans.
The effect of ensiling and fractionation on the suitability for combustion of three common grassland species at sequential harvest dates
Authors: McEniry J. , Finnan J. , King C. , O'Kiely P. 
Published: August 2012

AbstractIn a Green Biorefinery processing green biomass, one possible application for the press‐cake fraction is as biomass fuel for combustion. In an industrial setting, the preservation of herbage as silage and its subsequent fractionation into press‐juice and press‐cake fractions represent the two major process steps in the utilization of green biomass. This study investigated (i) the effects of ensiling and fractionation on the chemical composition of three common temperate grassland species harvested at different stages of maturity and (ii) the suitability of the herbage of these species for thermal combustion. The high contents of ash, N, Cl and K in perennial ryegrass, cocksfoot and red clover, at both pre‐ and post‐ensiling, make these materials less suitable for combustion in certain applications. The loss of soluble/fermentable organic matter during ensiling increased the relative proportions of fibre, ash and N in the herbage, but these changes were relatively minor. In contrast, the substantial reduction in the concentration of compounds such as ash, N, Cl and K during fractionation improved the suitability of the press‐cake fraction for combustion compared with the parent material. Press‐cake prepared from later‐harvested grass herbage with lower ash, S and N contents would be more suitable for combustion.
Novel mutations in calcium/calmodulin‐dependent protein kinase IV (CAMK4) gene in infertile men
Authors: Khattri A. , Reddy V. P. , Pandey R. K. , Sudhakar D. V. S. , Gupta N. J. , Chakravarty B. N. , Deenadayal M. , Singh L. , Thangaraj K. 
Published: August 2012

SummaryCalcium/calmodulin‐dependent protein kinase IV (CAMK4) is a multifunctional serine/threonine protein kinase, which plays an important role in the spermatogenesis by phosphorylating protamines. It has been shown to be involved in the regulation of human sperm motility. Moreover, the Camk4 knockout mice were infertile because of severely reduced sperm count and morphological abnormalities. As no study is available on the association of this gene with male infertility, we analysed all the exons of CAMK4 gene in ethnically matched 283 infertile and 268 fertile Indian men. We identified twenty nucleotide substitutions, of which twelve were novel. Of these novel variants, eight were exclusively detected in infertile men. Moreover, two infertile men‐specific mutations were non‐synonymous replacing amino acids at the highly conserved region. In silico analysis predicted both of these mutations as ‘deleterious’. In addition to nucleotide substitutions, we identified five novel insertion–deletion mutations; of these, g.150264_66delGCG was exclusively found in two oligoasthenoteratozoospermic men. In silico analysis of infertile men exclusive mutations predicted that they can alter/diminish the potential binding sites of splicing factors, which may affect the mRNA splicing and protein translation. Our study suggests that the mutations in CAMK4 may lead to abnormal semen parameters.
Does psychological well‐being mediate the association between experiences of acts of offensive behaviour and turnover among care workers? A longitudinal analysis
Authors: Clausen Thomas , Hogh Annie , Carneiro Isabella Gomes , Borg Vilhelm 
Published: August 2012

AbstractAimTo investigate whether the psychological well‐being of care workers in the Danish eldercare services mediated the association between experiences of acts of offensive behaviour and actual turnover.BackgroundResearch suggests that experiences of acts of offensive behaviour are associated with risk of turnover. However, little is known about the longitudinal associations between experiences of different types of offensive behaviour (threats, violence, bullying, and unwanted sexual attention) and risk of actual turnover.DesignA prospective cohort study.MethodsThe study was conducted among employees in the eldercare services in Denmark. Employees aged 55 or more and non‐care staff were excluded from the study. Employees who were working in eldercare at baseline (2005) and no longer worked in eldercare at follow‐up (2006) were interviewed through questionnaires. Respondents to this questionnaire were coded as cases of turnover (N = 608) and were compared with employees who had not changed jobs during follow‐up (N = 4330). Data on experiences of acts of offensive behaviour and well‐being were measured at baseline. Data were analysed using logistic regression analysis.ResultsFrequent and occasional experiences of bullying and threats and occasional experiences of unwanted sexual attention at baseline entailed a significantly increased risk of turnover at follow‐up. Further analyses showed that psychological well‐being significantly reduced the risk of turnover and that well‐being partially mediated the association between bullying and turnover and fully mediated the association between threats, unwanted sexual attention, and turnover.ConclusionPrevention of threats, unwanted sexual attention and – especially – bullying may contribute towards improving well‐being and reducing turnover among eldercare staff.
Patterns and controlling factors of species diversity in the Arctic Ocean
Authors: Yasuhara Moriaki , Hunt Gene , van Dijken Gert , Arrigo Kevin R. , Cronin Thomas M. , Wollenburg Jutta E. 
Published: August 2012

AbstractAim  The Arctic Ocean is one of the last near‐pristine regions on Earth, and, although human activities are expected to impact on Arctic ecosystems, we know very little about baseline patterns of Arctic Ocean biodiversity. This paper aims to describe Arctic Ocean‐wide patterns of benthic biodiversity and to explore factors related to the large‐scale species diversity patterns.Location  Arctic Ocean.Methods  We used large ostracode and foraminiferal datasets to describe the biodiversity patterns and applied comprehensive ecological modelling to test the degree to which these patterns are potentially governed by environmental factors, such as temperature, productivity, seasonality, ice cover and others. To test environmental control of the observed diversity patterns, subsets of samples for which all environmental parameters were available were analysed with multiple regression and model averaging.Results  Well‐known negative latitudinal species diversity gradients (LSDGs) were found in metazoan Ostracoda, but the LSDGs were unimodal with an intermediate maximum with respect to latitude in protozoan foraminifera. Depth species diversity gradients were unimodal, with peaks in diversity shallower than those in other oceans. Our modelling results showed that several factors are significant predictors of diversity, but the significant predictors were different among shallow marine ostracodes, deep‐sea ostracodes and deep‐sea foraminifera.Main conclusions  On the basis of these Arctic Ocean‐wide comprehensive datasets, we document large‐scale diversity patterns with respect to latitude and depth. Our modelling results suggest that the underlying mechanisms causing these species diversity patterns are unexpectedly complex. The environmental parameters of temperature, surface productivity, seasonality of productivity, salinity and ice cover can all play a role in shaping large‐scale diversity patterns, but their relative importance may depend on the ecological preferences of taxa and the oceanographic context of regions. These results suggest that a multiplicity of variables appear to be related to community structure in this system.
Causes of tree line stability: stem growth, recruitment and mortality rates over 15 years at New Zealand Nothofagus tree lines
Authors: Harsch Melanie A. , Buxton Rowan , Duncan Richard P. , Hulme Philip E. , Wardle Peter , Wilmshurst Janet 
Published: August 2012

AbstractAimAbrupt tree lines are relatively rare world‐wide and are poorly understood. We studied demographic processes at abrupt tree lines to better understand the factors governing their dynamics.LocationFive Nothofagus‐dominated tree line sites across the South Island, New Zealand.MethodsAll Nothofagus stems at or above the tree line were tagged and their spatial locations and heights recorded on three occasions over 15 years at each site. We estimated rates of stem height growth, recruitment and mortality, and used these data to develop a demographic model to project stem numbers into the future.ResultsStem numbers had increased above the tree line at most sites over the last 15 years, but with little evidence of tree line advance. Growth, mortality and recruitment rates, modelled as a function of stem size, showed variation through time and among sites. Using a demographic model to project the numbers of stems above tree line 15 years into the future suggests that stem number will continue to increase, but that these tree lines are unlikely to advance at the rate predicted by recent climate warming. Across sites, variation in the rate of change in the number of stems above the tree line was most strongly related to variation in recruitment rates.Main conclusionsForest expansion at the abrupt Nothofagus tree line in New Zealand appears to be limited primarily by a lack of recruitment of new stems, which may be due to a paucity of suitable sheltered microsites for seedling establishment. Based on past demographic rates, our results suggest that these tree lines are relatively unresponsive to recent climate warming and are unlikely to show substantial upslope movement if past demographic trends continue.