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Hydrothermal vents are a well-known source of energy that powers chemosynthesis in the deep sea. Recent work suggests that microbial chemosynthesis is also surprisingly pervasive throughout the dark oceans, serving as a significant CO2 sink even at sites far removed from vents. Ammonia and sulfur have been identified as potential electron donors for this chemosynthesis, but they do not fully account for measured rates of dark primary production in the pelagic water column. Here we use metagenomic and metatranscriptomic analyses to show that deep-sea populations of the SUP05 group of uncultured sulfur-oxidizing Gammaproteobacteria, which are abundant in widespread and diverse marine environments, contain and highly express genes encoding group 1 Ni, Fe hydrogenase enzymes for H2 oxidation. Reconstruction of near-complete genomes of two cooccurring SUP05 populations in hydrothermal plumes and deep waters of the Gulf of California enabled detailed population-specific metatranscriptomic analyses, revealing dynamic patterns of gene content and transcript abundance. SUP05 transcripts for genes involved in H2 and sulfur oxidation are most abundant in hydrothermal plumes where these electron donors are enriched. In contrast, a second hydrogenase has more abundant transcripts in background deep-sea samples. Coupled with results from a bioenergetic model that suggest that H2 oxidation can contribute significantly to the SUP05 energy budget, these findings reveal the potential importance of H2 as a key energy source in the deep ocean. This study also highlights the genomic plasticity of SUP05, which enables this widely distributed group to optimize its energy metabolism (electron donor and acceptor) to local geochemical conditions. [ABSTRACT FROM AUTHOR]

A few months before its "official" discovery in September 1932 by Anderson at Cal Tech in Pasadena, the positron was almost simultaneously observed by no less than two additional research teams: one at Cavendish Laboratory in Cambridge, England, and one at Institut du Radium in Paris, France. In this paper, we examine this curious case of multiple independent observations by studying the primary literature. This study identifies the motivations that led these researchers to independently design the experiments suitable for the detection of this novel particle and shows that none of these teams were looking for a positive electron. [ABSTRACT FROM AUTHOR]

In the autumn of 1986, the first electron beam ion trap, EBIT, was put into service as a light source for the spectroscopy of highly charged ions. On the occasion of the twentieth anniversary of EBIT, we review its early uses for spectroscopy, from the first measurements of X-rays from L-shell xenon ions in 1986 to its conversion to SuperEBIT in 1992 and rebirth as EBIT-I in 2001. Together with their sibling, EBIT-II, these machines have been used at Livermore to perform a multitude of seminal studies of the physics of highly charged ions.PACS Nos.: 01.65.+g, 32.30.–r, 32.30,Rj, 39.10.+j [ABSTRACT FROM AUTHOR]

Redox status of shallow groundwaters (1-3 m depths) at Owens Dry Lake was studied to help guide mitigation efforts for attenuating dust generation from the dry lakebed. Redox conditions were characterized by Eh, oxidative capacity (OXC), and terminal electron accepting processes (TEAP5) as well as examining the energetics of TEAPs. Groundwater chemistry related to redox status was determined by major solute concentrations, dissolved gases (02, H2, CH4), aqueous redox species (NO3-, Mn2&plus;, Fe2&plus;/ Fe3&plus; S042-/HS-, DOC), and major redox sensitive components in the solid phase (extractable Fe/Mn). All of these measures of redox status indicate that sulfate reduction is the major process regulating redox conditions in most shallow groundwaters of Owens Dry Lake. Dissolved sulfate concentrations were regulated primarily by evaporation resulting in increasing concentrations as water migrates from the shoreline (<1 mM) to the center (up to 417 mM) of the dry lakebed. Eh values were generally in the range of -240 to -170 mV. The oxidative capacity demonstrates the dominant contribution of sulfate to OXC. The dominance of sulfate restricts further reclox development, such as methanogenesis. Dissolved H2 concentrations ranged from 0.5 to 7.8 nM. According to the empirically defined H2 ranges, sulfate reduction was the most predominant TEAP. Moreover, thermodynamic calculations of TEAPs for H2 utilization support favorable energetics for both sulfate reduction and methanogenesis. The calculated available energy yield for sulfate reduction in the shallow groundwater of Owens Dry Lake was higher than other systems due to the high sulfate concentration. [ABSTRACT FROM AUTHOR]

The article reports on the emergence of excitonic transistor, a new interconnect technology which uses excitons as signal carriers. It notes that excitons can be engineered in traditional semiconductors by confining the electron and hole in the quantum well. Meanwhile, it says that the team at University of California in San Diego (UCSD) and University of California in Santa Barbara (UCSB) have revealed the advantages of the excitons such as its tiny size and its directly modulated current.

The article highlights a study on bottomonium (B) ground state. It explores the founding of bottomunium ground state based on the study conducted by PEPII electron-position collider at Stanford Linear Accelerator Center and continued by BaBar collaboration. BaBar collaboration, which operated the so-called B-factory's detector, decided it would be useful to run the collider at several collision energies below the threshold for making B pairs. Details on the result of the study are discussed.

The article focuses on the research conducted in 2007 by theoretical physicists from California and experimental physicists in Germany which predicted that semiconductor sandwiches with thin layers of mercury telluride in the middle will exhibit quantum spin Hall effect (QSHE). The author inferred that QSHE is an unusual behavior of electrons when placed in an electric or magnetic field. The author averred that performing QSHE at room temperature could lead to the development of new low-power spintronic computing devices that manipulate electrons by both charge and spin.

Discusses a study on electrons in water clusters conducted by Daniel Neumark and colleagues from the University of California in Berkeley, California as of March 2005. Types of anionic-cluster isomers created by Neumark and colleagues; Problem concerning the behavior of electrons in modest-sized water clusters; Other studies probing into to the behavior of electrons in water clusters.

California-based Bloom Energy has announced the Bloom Electrons™ service, which gives customers the flexibility to purchase electricity provided by its solid oxide fuel cell powered Bloom Box without incurring any other costs. The company says that more than 20 MW worth of 24/7 electricity service (representing 200 of its 100 kW Bloom Boxes) has already been secured. [Copyright &y& Elsevier]

Neoclassical tearing modes (NTMs) are experimentally controlled with local electron cyclotron current drive (ECCD) and the island width decay during NTM stabilization is modelled using the so-called modified Rutherford equation (MRE). In this paper, a modelling of the MRE is carried out and simulations of the island width decay are compared with the experimentally observed ones in order to fit the two free machine-independent parameters present in the equation. A systematic study on a database of NTM stabilization discharges from ASDEX Upgrade and JT-60U is done for extrapolating the ECCD power requirements for ITER. The extrapolation to ITER of the NTM stabilization results from ASDEX Upgrade and JT-60U shows that 10 MW of ECCD power are enough to stabilize large NTMs. The 10 MW power estimate for ITER is based on the assumption that the free parameters in the MRE are machine independent. Indeed, this assumption is verified in this paper for ASDEX Upgrade and JT-60U. An interesting consequence of the relatively modest power requirement for ITER is that the installed 20 MW will suffice for simultaneous 2/1 and 3/2 NTM stabilization. [ABSTRACT FROM AUTHOR]

A shell-like polycrystalline grain (ca. 1 mm) of W-(Mo)-bearing Os-Ir alloy (11.4-18.6 wt% W; up to 1.5% Mo) is present in a very old collection (probably the 1890s) of tiny nuggets from Trinity Co., California. An extensive compositional series [(Os0.43-0.80Ir0.28-0.05) W0.12-0.18], and inverse Ir-Os correlation, are observed; the mean composition [Os0.676W0.153Ir0.124Fe0.021Mo0.015Ru0.011; Σatoms = 1], based on results of 50 electron-microprobe analyses, displays a ratio (Os + Ir):W of 5:1. The observed variations and element correlations suggest that (W + Mo) contents are controlled by Ir, and incorporated via the following substitution scheme: [(W + Mo) + Ir] ↔ Os. The X-ray diffraction data indicate that the W-rich alloy has a hexagonal close-packed structure, related to that of osmium and allargentum, with a = 2.7297(4) Å, c = 4.3377(6) Å, and V = 27.99(1) ų the c:a ratio is 1.59. The probable space-group is P63/mmc, and Z = 2; the calculated density is 21.86(1) g/cm³. The W-rich alloy is associated with an Os-Ru-Ir alloy rich in Fe (7.0-9.7 wt%), which exhibits atomic Fe ↔ [Os + Ru] and Ir ↔ [Os + Ru] mechanisms of substitution. We suggest that these W-(Mo)- and Fe-rich alloys formed by metasomatic alteration of a primary Os-Ir-Ru alloy, associated with mineralized ultramafic-mafic rocks of ophiolite afffinity. A fluid phase may well have remobilized and transported W, Mo, and Fe. The W-rich alloy likely crystallized from a reducing fluid under conditions of low fugacities of O2 and S2, thus promoting the observed siderophile behavior of W and Mo. These unusual W-(Mo)- and Fe-rich alloy grains were likely derived, as a placer material, from the Trinity ophiolite complex of northern California. [ABSTRACT FROM AUTHOR]

Lechtman, M. D. (University of Southern California, Los Angeles), J. W. Bartholomew, A. Phillips, and M. Russo. Rapid methods of staining bacterial spores at room temperature. J. Bacteriol. 89:848-854. 1965.-Spores of Bacillus subtilis var. niger were stained in 2 min at room temperature, after suitable pretreatment, with a dye reagent composed of 2% crystal violet in 1% phenol and 26% ethanol. Pretreatments included heat fixation to 260 C, mechanical rupture, and hydrolysis at room temperature in 44 n H(3)PO(4) for 5 min, 33.4 n H(3)PO(4) for 10 min, 12 n HCl for 5 sec, 6 n HCl for 2 min, 12 n HNO(3) for 5 sec, and 6 n HNO(3) for 60 sec. Acid hydrolysis at 60 C enabled the lowering of both acid concentration and time: 33.4 n H(3)PO(4) for 15 sec, 25.9 n H(3)PO(4) for 60 sec, 2 n HCl for 30 sec, 1 n HCl for 30 sec, 2 n HNO(3) for 15 sec, and 1 n HNO(3) for 30 sec. After acid treatment, 1 n NaOH was used as a neutralization agent. The cytological manifestations of these pretreatments, examined in an electron microscope after replication, showed definite degradation of spore coats, which probably explains the increase in dye permeability. The pretreatments were evaluated for use in a differential staining procedure for spores and vegetative cells. They were found to be too drastic in that they resulted in replacement of the primary dye by the 0.25% safranine counter stain in both vegetative cells and endospores. Less drastic pretreatments, such as 6 n HNO(3) for 10 sec at room temperature, gave good differential stains, but failed to stain some free spores. The staining techniques above were evaluated with six species of Bacillus and were found to apply to all.