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We searched for shocked carbon chain chemistry (SCCC) sources with C3S abundances surpassing those of HC5N toward the dark cloud L1251, using the Effelsberg telescope at the K band (18–26 GHz). L1251-1 and L1251-3 are identified as the most promising SCCC sources. The two sources harbor young stellar objects. We conducted mapping observations toward L1251-A, the western tail of L1251, at λ ∼ 3 mm with the Purple Mountain Observatory 13.7 m and the Nobeyama Radio Observatory 45 m telescopes in lines of C2H, N2H+, CS, HCO+, SO, HC3N, and C18O as well as in CO 3–2 using the James Clerk Maxwell Telescope (JCMT). The spectral data were combined with archival data including Spitzer and Herschel continuum maps for further analysis. Filamentary substructures labeled as F1–F6 were extracted in L1251, with F1 being associated with L1251-A hosting L1251-1. The peak positions of dense gas traced by HCO+ are misaligned relative to those of the dust clumps. Episodic outflows are common in this region. The twisted morphology of F1 and velocity distribution along L1251-A may originate from stellar feedback. SCCC in L1251-1 may have been caused by outflow activities originated from the infrared source IRS1. The signposts of ongoing SCCC and the broadened line widths of C3S and C4H in L1251-1 as well as the distribution of HC3N are also related to outflow activities in this region. L1251-1 (IRS1) together with the previously identified SCCC source IRS3 demonstrate that L1251-A is an excellent region to study SCCC. [ABSTRACT FROM AUTHOR]

We investigate the photoluminescence (PL) behavior of the porous silicon nanowire (PSiNW) arrays synthesized via metal-assisted electroless etching method on the n-Si (100) substrate. Two PL bands with different origins dependent on the post-chemical treatments were detected. The red emission band, the peak position of which is insensitive to temperature and excitation source, is considered to originate from the excitons localized at the interface between the Si nanostructure and the oxide layer. An anomalous blue shift of the near-infrared PL band was observed when the temperature increased from 80 to 290 K. The maximum intensity appears around 160 K and the emission energy is strongly dependent on the excitation energy and power. The triplet-singlet state transition is introduced to explain the PL behavior for this emission band. The absorption spectra are also induced to confirm the PL origins. [ABSTRACT FROM AUTHOR]

Variable temperature photoluminescence (PL) measurement of a thermal-annealed 6 nm GaInNAs/GaAs quantum well (QW) is carried out to understand its low-temperature carrier dynamic characteristics. It is found that the effect of carrier localization, which remained after a thermal anneal, is due possibly to a center characterized by a transition with activation energy of 13.7 meV below the e1 state. This result is deduced from fitting the integrated PL intensity versus the temperature data with a single-activation-energy model. A comparable value of 11 meV was also obtained between the low-energy (main localized state) and high-energy (e1 state) Gaussian functions used to fit the low-temperature PL spectrum. The localization effect in the thermal-annealed GaInNAs/GaAs QW is further confirmed by time-resolved PL measurements at 17 K, which showed emission-energy-dependent PL decay time characteristic for the low-energy regime (below 1.045 eV) and nearly constant decay time of about 0.14 ns at the high-energy regime, which corresponds to the e1-hh1 transition lifetime. The main localization center could form carrier traps that reduce the e1-hh1 PL transition efficiency. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Xanthomonas albilineans is the causal agent of leaf scald, a disease that can cause considerable damage to sugarcane industries. This study analysed the phylogenetic relationship of 14 samples of X. albilineans from China and 13 reference strains retrieved from the GenBank database by multilocus sequence analysis (MLSA). To reach this goal, five housekeeping genes of X. albilineans were amplified from diseased leaves and sequenced: gyrB, abc, rpoD, atpD and glnA. Based on the concatenated sequence of these genes (4473 nt), the 14 samples of X. albilineans from China had 99.9–100% sequence identity with one another and with five strains of the pathogen from the French West Indies and the USA (Florida). The 27 samples or strains of X. albilineans were distributed in two distinct clades in the MLSA‐based phylogenetic tree. Clade 1 was formed by four strains of the pathogen from Fiji, Papua New Guinea and the USA. All the other strains from worldwide locations, including the 14 samples from China, were grouped in clade 2. This latter clade included all strains of the pathogen that were associated with outbreaks of leaf scald that have occurred over the last two decades, especially in the Caribbean islands and the USA. The very low diversity of X. albilineans in four Chinese provinces suggests recent spread of a single strain (from genetic group PFGE‐B) of the leaf scald pathogen within China. [ABSTRACT FROM AUTHOR]

We investigate the energy relaxation of hot carriers in a CVD-grown graphene device with a top h-BN layer by driving the devices into the nonequilibrium regime. By using the magnetic field dependent conductance fluctuations of our graphene device as a self-thermometer, we can determine the effective carrier temperature Te at various driving currents I while keeping the lattice temperature TL fixed. Interestingly, it is found that Te is proportional to I, indicating little electron-phonon scattering in our device. Furthermore the average rate of energy loss per carrier Pe is proportional to (Te 2-TL 2), suggesting the heat diffusion rather than acoustic phonon processes in our system. The long energy relaxation times due to the weak electron-phonon coupling in CVD graphene capped with h-BN layer as well as in exfoliated multilayer graphene can find applications in hot carrier graphene-based devices. [ABSTRACT FROM AUTHOR]

The International Continental Scientific Drilling Program (ICDP) has long espoused studies of deep subsurface life, and has targeted fundamental questions regarding subsurface life, including the following: "(1) What is the extent and diversity of deep microbial life and what are the factors limiting it? (2) What are the types of metabolism/carbon/energy sources and the rates of subsurface activity? (3) How is deep microbial life adapted to subsurface conditions? (4) How do subsurface microbial communities affect energy resources? And (5) how does the deep biosphere interact with the geosphere and atmosphere?" (Horsfield et al., 2014) Many ICDP-sponsored drilling projects have included a deep-life component; however, to date, not one project has been driven by deep-life goals, in part because geomicrobiologists have been slow to initiate deep biospheredriven ICDP projects. Therefore, the Deep Carbon Observatory (DCO) recently partnered with the ICDP to sponsor a workshop with the specific aim of gathering potential proponents for deep-life-driven ICDP projects and ideas for candidate drilling sites. Twenty-two participants from nine countries proposed projects and sites that included compressional and extensional tectonic environments, evaporites, hydrocarbon-rich shales, flood basalts, Precambrian shield rocks, subglacial and subpermafrost environments, active volcano–tectonic systems, megafan deltas, and serpentinizing ultramafic environments. The criteria and requirements for successful ICDP applications were presented. Deep-life-specific technical requirements were discussed and it was concluded that, while these procedures require adequate planning, they are entirely compatible with the sampling needs of other disciplines. As a result of this workshop, one drilling workshop proposal on the Basin and Range Physiographic Province (BRPP) has been submitted to the ICDP, and several other drilling project proponents plan to submit proposals for ICDP-sponsored drilling workshops in 2016. [ABSTRACT FROM AUTHOR]

A new method of preparing iron oxyhydroxide was developed, in which nanoclusters were precipitated from heated aqueous Fe(NO3)3 solution through promotion by CuO. The products of this reaction were characterised. The composition of the products changed with the content of CuO added, but no copper ferrite or solid solution was identified. When the molar ratio of CuO to Fe(NO3)3 was limited to 1∶1, the products were nanoclusters consisting of very small Fe5O7(OH).4H2O ferrihydrite (FH) crystallites. The nanoclusters adsorbed a small amount of Fe(NO3)3, which decreased as the amount of CuO increased when the molar ratio of CuO to Fe(NO3)3 was less than 1∶1. When the molar ratio of the precursors exceeded 1∶1, the amount of Fe(NO3)3 adsorbed onto the FH nanoclusters decreased, and Cu2(OH)3NO3 was found in the precipitate. The experimental results were attributed to the hydrolysis of Fe(NO3)3 being enhanced by CuO acting as a hydrolyte. Saturation behaviour was observed for the addition of CuO. This is a new route to prepare oxide nanoclusters by enhanced hydrolysis. [ABSTRACT FROM AUTHOR]

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An in situ culturing device was incubated within a flowing borehole in a mafic sill at 1.474 km depth in Evander Au mine, South Africa. The device was designed to enrich methanogenic, Fe3 +-reducing and SO42 --reducing microorganisms using acetate, formate, methanol, Fe3 +-citrate and SO42 - enriched agar and sand cartridges. At the end of the 33 day incubation geochemical analyses detected elevated H2, acetate, CH4 and Fe concentrations and depleted SO42 - concentrations. 16S rDNA sequences and PLFA analyses revealed that the microbial community composition of the substrate-bearing cartridges were distinct from that of the original borehole water and the non-substrate-bearing control cartridge. 16S rDNA and dissimilatory sulfite reductase, dsrAB, gene sequences indicated the device successfully targeted SO42 - reducing bacteria (SRB), which were not detected in the original borehole water. 16S rDNA sequences also revealed a shift in the microbial community from one relying on H2 based methanogenesis to one suggestive of H2 based acetogenesis supporting aceticlastic methanogenesis and SO42 - reduction compatible with the subsurface lithoautotrophic hypothesis. [ABSTRACT FROM AUTHOR]

Gene transfer has been used to examine the role of putative neurotransmitters in the nucleus tractus solitarii (NTS). Most such studies used adenovirus vector-mediated gene transfer although adenovirus vector transfects both neuronal and non-neuronal cells. Successful transfection in the NTS has also been reported with lentivirus as the vector. Feline immunodeficiency virus (FIV), a lentivirus, may preferentially transfect neurons and could be a powerful tool to delineate physiological effects produced by altered synthesis of transmitters in neurons. However, it has not been studied in NTS. Therefore, we sought to determine whether FIV transfects rat NTS cells and to define the type of cell transfected. We found that injection of FIV encoding LacZ gene (FIVLacZ) into the NTS led to transfection of numerous NTS cells. Injection of FIVLacZ did not alter immunoreactivity (IR) for neuronal nitric oxide synthase, which we have shown resides in NTS neurons. A majority (91.7 ± 3.9%) of transfected cells contained IR for neuronal nuclear antigen, a neuronal marker; 2.1 ± 3.8% of transfected cells contained IR for glial fibrillary acidic protein, a glial marker. No transfected neurons or fibers were observed in the nodose ganglion, which sends afferents to the NTS. We conclude that FIV almost exclusively transfects neurons in the rat NTS from which it is not retrogradely transported. The cell-type specificity of FIV in the NTS may provide a molecular method to study local physiological functions mediated by potential neurotransmitters in the NTS. [ABSTRACT FROM AUTHOR]

CD4+CD25+bright T cells played a crucial role in the suppression of immune response. Recently, decreased levels of CD4+CD25+bright T cells in the peripheral blood of patients with systemic lupus erythematosus were reported, suggesting the potential role of CD4+CD25+bright T cells in human autoimmune diseases. Primary Sjögren's syndrome (pSS) is another common human systemic autoimmune disease. The present study aimed to investigate the levels of CD4+CD25+bright T cells in pSS and to correlate their levels with some biomarkers of inflammation and immune activation. Thirty-three patients with pSS and 35 age- and sex-matched normal individuals were enrolled in the study. The flowcytometric method was applied in the measurement of CD4+CD25+bright T cells. The results showed that patients with pSS had statistically lower levels of CD4+CD25+bright T cells than normal controls, expressed either as absolute cell numbers (mean ± SD: 47.07 ± 25.53 cells/mm³ versus 79.55 ± 34.56 cells/mm³, P < 0.001) or as percentages of peripheral blood mononuclear cells (mean ± SD: 2.79 ± 1.06% versus 3.84 ± 1.42%, P < 0.001) or as percentages of CD4+ T cells (mean ± SD: 7.85 ± 2.62% versus 11.68 ± 3.78%, P < 0.005). Moreover, there were statistically significant inverse correlations between the levels of CD4+CD25+bright T cells and some parameters of inflammation or immune activation including erythrocyte sedimentation rate, C-reactive protein, IgG and rheumatoid factors. The result suggested that CD4+CD25+bright T cells were likely to play anti-inflammatory and immunosuppressive roles in the pathogenesis of pSS. However, the exact functions of decreased circulating CD4+CD25+bright T cells in pSS need further elucidated. [ABSTRACT FROM AUTHOR]

The maternal manipulation hypothesis for the evolution of reptilian viviparity has been claimed to apply to any situation where gravid females are able to maintain body temperatures different from those available in external nests, but empirical data that support this hypothesis are very limited. Here, we tested this hypothesis using gravid females of a warm-climate lizard, Mabuya multifasciata, by subjecting them to five thermal regimes for the whole gestation period. We found gravid females selected lower body temperatures and thermoregulated more precisely than did nongravid females. Offspring produced in different treatments differed in head size, limb length and sprint speed, but not in overall body size or mass. Variation in morphological traits of offspring was induced primarily by extreme temperatures. Sprint speed of offspring was more likely affected by the mean but not by the variance of gestation temperatures. Gravid females maintained more stable body temperatures than did nongravid females not because these temperatures resulted in the optimization of offspring phenotypes but because the range of temperatures optimal for embryonic development was relatively narrow. Our data conform to the main predictions from the maternal manipulation hypothesis that females should adjust thermoregulation during pregnancy to provide optimal thermal conditions for developing embryos and that phenotypic traits forged by maternal thermoregulation should enhance offspring fitness. [ABSTRACT FROM AUTHOR]

Water residing within crustal fractures encountered during mining at depths greater than 500 meters in the Witwatersrand basin of South Africa represents a mixture of paleo-meteoric water and 2.0-23 Ga hydrothermal fluid. The hydrothermal fluid is highly saline, contains abiogenic CH4 and hydrocarbon, (occasionally N2, originally formed at ∼250-300°C and during cooling isotopically exchanged O and H with minerals and accrued H2,4He and other radiogenic gases. The paleo-meteoric water ranges in age from ∼10 Ka to >1.5 Ma, is of low salinity, falls along the global meteoric water line (GMWL) and is CO2 and atmospheric noble gas-rich. The hydrothermal fluid, which should he completely sterile, has probably been mixing with paleo-meteoric water for at least the past ∼100 Myr, a process which inoculates previously sterile environments at depths >2.0 to 2.5 km. Free energy flux calculations suggest that sulfate reduction is the dominant electron acceptor microbial process for the high salinity fracture water and that it is 107 times that normally required for cell maintenance in lab cultures. Flux calculations also indicate that the potential bioavailable chemical energy increases with salinity, but because the fluence of bioavailable C, N and P also increase with salinity, the environment remains energy-limited. The 4He concentrations and theoretical calculations indicate that the H2 that is sustaining the subsurface microbial communities (e.g. H2-utilizing SRB and methanogens) is produced by water radiolysis at a rate of ∼1 nMyr ¹. Microbial CH4 mixes with abiogenic CH4 to produce the observed isotopic signatures and indicates that the rate of methanogenesis diminishes with depth from ∼100 at <1 kmbls, to <0.01 nM yr ¹at >3 kmbls. Microbial Fe(III) reduction is limited due to the elevated pH. The δ13C of dissolved inorganic carbon is consistent with heterotrophy rather than autotrophy dominating the deeper, more saline environments. One potential source of the organic carbon may he microfilms present on the mineral surfaces. [ABSTRACT FROM AUTHOR]

Microbial communities within deep subsurface environments were analyzed by 16S rRNA gene cloning. Clone libraries from 27 borehole fluid, 7 mining-contaminated, and 5 rock samples were compared. Borehole fluids derived from deep fractures were populated by microbial communities with low diversity with an average of 11 and 5 bacterial and archaeal OTUs respectively. Low taxa richness was likely driven by limited biogeochemical reactions available for growth and not extreme parameters such as pH and temperature. Novel taxa of Firmicutes were discovered, commonly found in warm, slightly alkaline, anoxic fracture fluids. Highly divergent lineages of Archaea, unique to South African deep subsurface fracture fluids, are also described. Clone library clustering analyses based on LIBSHUFF phylogenetic relatedness revealed distinct groups of samples corresponding with sample source and geochemistry. [ABSTRACT FROM AUTHOR]

CD4+CD25+ T cells have been shown to play a regulatory or suppressive role in the immune response and are possibly relevant to the pathogenesis of autoimmune diseases. In the present study, we attempted to investigate the levels of CD4+CD25+ T cells in the peripheral blood (PB) and synovial fluid (SF) of patients with rheumatoid arthritis (RA) and the effects of CD4+CD25+ T cells on the in vitro cytokine production by stimulated SF mononuclear cells (SFMC). The results showed that RA patients had similar frequencies of CD4+CD25+ T cells in PB, expressed as a percentages of the lymphocyte population, as did healthy subjects (mean ± SD: 10.52 ± 5.87% versus 11.11 ± 4.58%., respectively). But in contrast to PB, the SF of RA patients contained significantly higher levels of CD4+CD25+ T cells (17.77 ± 7.92% versus 10.52 ± 5.87%, respectively. P < 0.001). When cocultured in vitro with SFMC, CD4+CD25+ T cells purified from either PB or SF were found to exert a considerable suppressive effect on the production of cytokines including TNF-α, IFN-γ and interleukin-10 (IL-10). The percentages of inhibition of each cytokines ranged from 41.8 to 98.4% (mean, 80.0%) for TNF-α, 42.8 to 98.9% (mean, 83.2%) for IFN-γ and 59.3 to 96.6% (mean, 80.0%) for IL-10. Because both pro-inflammatory and anti-inflammatory cytokines were suppressed by CD4+CD25+ T cells, whether CD4+CD25+ T cells might play a beneficial role in the suppression of sustained inflammation in rheumatoid synovium remains to be elucidated. [ABSTRACT FROM AUTHOR]

Ectopic pancreas is relatively uncommon and usually occurs in the stomach or duodenum. Retroperitoneal ectopic pancreas has not previously been documented. We report the case of a 48-year-old man with retroperitoneal ectopic pancreas that imitated bilateral adrenal tumours on ultrasound and MRI. Subsequent CT-guided biopsies confirmed an ectopic pancreas. The lesions remained stable during follow-up for 7 years. In retrospect, the similarity in signal intensities and enhancement pattern between the retroperitoneal masses and the pancreas may have been a clue to the diagnosis of this rare entity. [ABSTRACT FROM AUTHOR]