bluuebunny/crossref_metadata_2025_split huggingface dataset:
Velocity dependence of shear‐induced permeability associated with frictional behavior in fault zones of the Nankai subduction zone
Authors: Tanikawa Wataru , Mukoyoshi Hideki , Tadai Osamu , Hirose Takehiro , Tsutsumi Akito , Lin Weiren 
Published: March 2012

We measured frictional properties and permeability of core materials from the megasplay fault zone (site C0004) and the frontal thrust (site C0007) in the shallow part of the Nankai subduction zone. Permeability was measured before and after 7.9 m slip displacement at high (1.05 m/s) and low velocities (0.013 m/s) under normal stresses of 1.5 MPa using the rotary‐shear apparatus, from which we estimated the shear‐induced permeability change in an experimental fault gouge prepared from core material. Gouge permeability (10−18 m2) decreased after sliding for wet gouge and increased for dry gouge. The high‐velocity friction test under wet conditions yielded a smaller reduction in permeability than the low‐velocity test, whereas the opposite trend was observed in dry conditions. We attribute the differences in permeability to the effects of thermal/mechanical pore pressurization upon shear‐induced compaction. Symmetric boudin structures may represent evidence of hydrofracturing induced by pore fluid pressurization. The large friction coefficient of the megasplay fault material in the slow and wet friction tests is explained by homogeneous shear deformation and higher permeability that promotes faster shear‐induced compaction. The similarity in post‐shear permeability for the gouges from the both faults may account for the similar friction coefficients in high‐velocity friction, assuming that the pore fluid pressurization process controls high‐velocity frictional behavior. This velocity dependence on friction suggests that a large dynamic stress drop is expected for the megasplay fault, implying that large slip displacement followed by a giant tsunami is plausible when a rupture from depth propagates to the megasplay fault.
Upper‐mantle earthquakes beneath the Arafura Sea and south Aru Trough: Implications for continental rheology
Authors: Sloan R. A. , Jackson J. A. 
Published: March 2012

The extent and controls of long‐term elastic strength and seismicity in the upper continental lithospheric mantle (UCLM) are controversial topics in continental tectonics. One key issue is the scarcity of UCLM earthquakes, even where the UCLM is likely to be colder than 600°C. The rarity of these earthquakes could be because the UCLM generally relatively hydrous causing it to deform aseismically even when colder than 600°C, unless it is deforming at exceptionally high strain rates. Alternatively, the UCLM could be relatively anhydrous, and potentially seismogenic at temperatures below 600°C; in which case the rarity of UCLM earthquakes may be because areas where the UCLM is colder than 600°C have such a thick seismogenic layer, and such a cool mantle root, that they deform exceptionally slowly. The identification and study of UCLM earthquakes allows us to distinguish between these possibilities. Here we show that two earthquakes occurred in the UCLM beneath the epicontinental Arafura Sea. Both earthquakes occurred where the UCLM is probably cooler than 600°C and one of these earthquakes lies ∼25 km below the Moho in an region where there is no evidence of unusually high strain rates. There at least, it is probable that the UCLM is relatively anhydrous, and seismogenic at temperatures below 600°C. We also find evidence that regions where the UCLM is colder than 600°C also have a seismogenic lower crust. This results in a single, extremely strong layer comprising the entire crust and the UCLM down to the 600°C isotherm.
‘Candidatus Thermochlorobacter aerophilum:’ an aerobic chlorophotoheterotrophic member of the phylum Chlorobi defined by metagenomics and metatranscriptomics
Authors: Liu Zhenfeng , Klatt Christian G , Ludwig Marcus , Rusch Douglas B , Jensen Sheila I , Kühl Michael , Ward David M , Bryant Donald A 
Published: March 2012

Abstract
An uncultured member of the phylum Chlorobi, provisionally named ‘Candidatus Thermochlorobacter aerophilum’, occurs in the microbial mats of alkaline siliceous hot springs at the Yellowstone National Park. ‘Ca. T. aerophilum’ was investigated through metagenomic and metatranscriptomic approaches. ‘Ca. T. aerophilum’ is a member of a novel, family-level lineage of Chlorobi, a chlorophototroph that synthesizes type-1 reaction centers and chlorosomes similar to cultivated relatives among the green sulfur bacteria, but is otherwise very different physiologically. ‘Ca. T. aerophilum’ is proposed to be an aerobic photoheterotroph that cannot oxidize sulfur compounds, cannot fix N2, and does not fix CO2 autotrophically. Metagenomic analyses suggest that ‘Ca. T. aerophilum’ depends on other mat organisms for fixed carbon and nitrogen, several amino acids, and other important nutrients. The failure to detect bchU suggests that ‘Ca. T. aerophilum’ synthesizes bacteriochlorophyll (BChl) d, and thus it occupies a different ecological niche than other chlorosome-containing chlorophototrophs in the mat. Transcription profiling throughout a diel cycle revealed distinctive gene expression patterns. Although ‘Ca. T. aerophilum’ probably photoassimilates organic carbon sources and synthesizes most of its cell materials during the day, it mainly transcribes genes for BChl synthesis during late afternoon and early morning, and it synthesizes and assembles its photosynthetic apparatus during the night.
Spatial and temporal dynamics of the microbial community in the Hanford unconfined aquifer
Authors: Lin Xueju , McKinley James , Resch Charles T , Kaluzny Rachael , Lauber Christian L , Fredrickson James , Knight Rob , Konopka Allan 
Published: March 2012

Abstract
Pyrosequencing analysis of 16S rRNA genes was used to study temporal dynamics of groundwater bacteria and archaea over 10 months within three well clusters separated by ∼30 m and located 250 m from the Columbia River on the Hanford Site, WA. Each cluster contained three wells screened at different depths ranging from 10 to 17 m that differed in hydraulic conductivities. Representative samples were selected for analyses of prokaryotic 16S and eukaryotic 18S rRNA gene copy numbers. Temporal changes in community composition occurred in all nine wells over the 10-month sampling period. However, there were particularly strong effects near the top of the water table when the seasonal rise in the Columbia River caused river water intrusion at the top of the aquifer. The occurrence and disappearance of some microbial assemblages (such as Actinobacteria ACK-M1) were correlated with river water intrusion. This seasonal impact on microbial community structure was greater in the shallow saturated zone than deeper zone in the aquifer. Spatial and temporal patterns for several 16S rRNA gene operational taxonomic units associated with particular physiological functions (for example, methane oxidizers and metal reducers) suggests dynamic changes in fluxes of electron donors and acceptors over an annual cycle. In addition, temporal dynamics in eukaryotic 18S rRNA gene copies and the dominance of protozoa in 18S clone libraries suggest that bacterial community dynamics could be affected not only by the physical and chemical environment but also by top-down biological control.
Global dimming and brightening - evidence and agricultural implications.
Authors: Wild M. , Roesch A. , Ammann C. 
Published: March 2012

Abstract
There is growing observational evidence that the level of sunlight received at the Earth's surface is not stable over the years but undergoes substantial decadal changes. These changes, known popularly as global dimming and brightening, are related to anthropogenic air pollution, as well as changes for cloudiness. Here, we summarize the evidence and discuss the implications of these variations in biospheric growth in general and agricultural applications in particular. Emphasis is placed on implications for forest canopies, grassland and agricultural crop production. Yet not only the total amount of sunlight that the biosphere receives is important but also the relative portion of the direct and diffuse light. Increasing air pollution and cloudiness can alter this partitioning towards a higher relative portion of diffuse light, in addition to a reduction in the total amount of sunlight. This diffuse light can enhance photosynthesis, particularly in tall and dense vegetation canopies, as it is distributed more effectively within the canopy compared with direct solar radiation, which is only accessible to the outermost (sunlit) layers. Here, we conclude that the growth of tall canopies such as forests or crop fields may be favoured under global dimming conditions owing to the enhanced diffuse light, despite the overall reduction in the total amount of sunlight. On the other hand, under the same dimming conditions, the yield of grassland, with its shallow open canopy, may be reduced, as it has little benefit from the enhanced diffuse fraction, while suffering from a loss in the total amount of sunlight for photosynthesis. Variations in solar radiation therefore may have largely varying effects on agricultural production depending on the structure of the crop canopy.
Estimation of Tag Shedding and Reporting Rates for Lake Erie Jaw-Tagged Walleyes
Authors: Vandergoot Christopher S. , Brenden Travis O. , Thomas Michael V. , Einhouse Donald W. , Cook H. Andrew , Turner Mark W. 
Published: March 2012

Abstract
Since 1990, walleyes Sander vitreus in Lake Erie have been tagged annually with jaw tags to better understand the population dynamics and ecological characteristics of individual spawning populations. Although the data collected from this tagging program have been used for a variety of management purposes (e.g., estimating migration patterns, stock intermixing, and mortality rates), there has been only cursory examination of the shedding and reporting rates associated with the program. We used double tagging and high-reward tagging experiments to estimate tag shedding and reporting rates for jaw-tagged walleyes in Lake Erie. Double tagging of walleyes with jaw and passive integrated transponder (PIT) tags suggested that the tagging method and tagging agency contributed to the observed variability in both immediate (within 21 d of tagging) retention and chronic jaw tag shedding rates. Agency-specific model-averaged estimates of immediate tag retention ranged from 95% to 99%. For chronic shedding, model-averaged instantaneous rates (annual) ranged from 0.07 to 0.28. Jaw tag reporting rates, estimated via releases of high-reward tags in 1990 and 2000, varied among tagging years, tagging basins, and commercial and recreational fisheries. In general, tag reporting rates were higher for the recreational fishery (range, 33–55%) than for the commercial fishery (10–17%), and the reporting rates for both fisheries and tagging basins were found to have declined between 1990 and 2000. Uncertainty in the tag reporting rates was greater for the recreational fishery than for the commercial fishery. Our findings will benefit management of the economically important Lake Erie walleye fisheries by providing managers with robust tag shedding and reporting rate estimates, providing more reliable estimates of important dynamic rates (e.g., fishing and natural mortality) by correcting the long-term jaw tagging data set for these previously unaccounted for biases.
Received September 13, 2011; accepted November 30, 2011
Graphene formed on SiC under various environments: comparison of Si-face and C-face
Authors: Srivastava N , He Guowei , Luxmi  , Mende P C , Feenstra R M , Sun Yugang 
Published: March 2012

Abstract
The morphology of graphene on SiC {0 0 0 1} surfaces formed in various environments including ultra-high vacuum, 1 atm of argon and 10−6–10−4 Torr of disilane is studied by atomic force microscopy, low-energy electron microscopy and Raman spectroscopy. The graphene is formed by heating the surface to 1100–1600 °C, which causes preferential sublimation of the Si atoms. The argon atmosphere or the background of disilane decreases the sublimation rate so that a higher graphitization temperature is required, thus improving the morphology of the films. For the (0 0 0 1) surface, large areas of monolayer-thick graphene are formed in this way, with the size of these areas depending on the miscut of the sample. Results on the

surface are more complex. This surface graphitizes at a lower temperature than for the (0 0 0 1) surface and consequently the growth is more three-dimensional. In an atmosphere of argon the morphology becomes even worse, with the surface displaying markedly inhomogeneous nucleation, an effect attributed to unintentional oxidation of the surface during graphitization. Use of a disilane environment for the

surface is found to produce improved morphology, with relatively large areas of monolayer-thick graphene.
The structure of graphene grown on the SiC

surface
Authors: Hicks J , Shepperd K , Wang F , Conrad E H 
Published: March 2012

Abstract
Graphene grown on the SiC

surface is unique. Unlike graphene grown on the (0 0 0 1) surface, graphene grown on the

surface has higher electron mobilities and an unusual non-Bernal stacking. Its different electronic properties are associated with its stacking and the graphene–SiC interface. In this paper we discuss what is known about the structure of this material. In particular we will discuss the ordering in this material and how it is related to the interface structure. We update new ideas about the interface and stacking and contrast it with works from other groups. New evidence for how Si is removed from the interface is also given that provides some insight into the growth process and shows that graphene nucleation is not confined to screw dislocations. This has important implications for the viability of patterned graphene growth.
Structure and stability of the interface between graphene and 6H-SiC(0 0 0 −1) (3 × 3): an STM and ab initio study
Authors: Hiebel F , Magaud L , Mallet P , Veuillen J-Y 
Published: March 2012

Abstract
We examine in detail the structure and evolution upon annealing of the SiC(3 × 3) reconstruction which is known to be present at the interface between the SiC–C face substrate and the graphene layer for samples prepared in high vacuum. We use ab initio calculations to test the validity of proposed or classical structural models in comparison with scanning tunnelling microscopy (STM) images. We analyse the electronic structure of the bare surface and detect interface states which can pin the surface Fermi level. From a comparison of the signal coming from the bare and graphene-covered SiC(3 × 3) reconstruction we propose that the transparency of the graphene in high-bias STM images results from an enhancement of the local density of states of the interface plane by the graphene layer. We discuss the thermal stability of the SiC(3 × 3) surface, and show that it transforms more easily into the SiC(2 × 2)C reconstruction in the graphene-covered region than for the bare surface. This evolution generates both structural and electronic heterogeneities at the interface.
Effective theory of rotationally faulted multilayer graphene—the local limit
Authors: Kindermann M , First P N 
Published: March 2012

Abstract
Interlayer coupling in rotationally faulted graphene multilayers breaks the local sublattice-symmetry of the individual layers. Earlier we have presented a theory of this mechanism, which reduces to an effective Dirac model with space-dependent mass in an important limit. It thus makes a wealth of existing knowledge available for the study of rotationally faulted graphene multilayers. Agreement of this theory with a recent experiment in a strong magnetic field was demonstrated. Here we explore some of the predictions of this theory for the system in zero magnetic field at large interlayer bias, when it becomes local in space. We use that theory to illuminate the physics of localization and velocity renormalization in twisted graphene layers.
Model and simulations of the epitaxial growth of graphene on non-planar 6H–SiC surfaces
Authors: Ming Fan , Zangwill Andrew 
Published: March 2012

Abstract
We study step flow growth of epitaxial graphene on 6H–SiC using a one-dimensional kinetic Monte Carlo model. The model parameters are effective energy barriers for the nucleation and propagation of graphene at the SiC steps. When the model is applied to graphene growth on vicinal surfaces, a strip width distribution is used to characterize the surface morphology. Additional kinetic processes are included to study graphene growth on SiC nano-facets. Our main result is that the original nano-facet is fractured into several nano-facets during graphene growth. This phenomenon is characterized by the angle at which the fractured nano-facet is oriented with respect to the basal plane. The distribution of this angle across the surface is found to be related to the strip width distribution for vicinal surfaces. As the terrace propagation barrier decreases, the fracture angle distribution changes continuously from two-sided Gaussian to one-sided power law. Using this distribution, it will be possible to extract energy barriers from experiments and interpret the growth morphology quantitatively.
Toroidal velocity shear Kelvin–Helmholtz instabilities in strongly rotating tokamak plasmas
Authors: Chapman I.T. , Brown S. , Kemp R. , Walkden N.R. 
Published: March 2012

Abstract
Strong sheared toroidal flows are predicted to drive parallel velocity shear Kelvin–Helmholtz oscillations unstable in spherical tokamak plasmas. Numerical simulations that include rotation in the equilibrium suggest that future spherical tokamaks will have an upper limit in uni-directional injected neutral beam heating in order to keep the sheared toroidal rotation below the critical level for the onset of the global parallel velocity shear Kelvin–Helmholtz instability.
IDSA Clinical Practice Guideline for Acute Bacterial Rhinosinusitis in Children and Adults
Authors: Chow Anthony W. , Benninger Michael S. , Brook Itzhak , Brozek Jan L. , Goldstein Ellie J. C. , Hicks Lauri A. , Pankey George A. , Seleznick Mitchel , Volturo Gregory , Wald Ellen R. , File Thomas M. 
Published: March 2012

AbstractEvidence-based guidelines for the diagnosis and initial management of suspected acute bacterial rhinosinusitis in adults and children were prepared by a multidisciplinary expert panel of the Infectious Diseases Society of America comprising clinicians and investigators representing internal medicine, pediatrics, emergency medicine, otolaryngology, public health, epidemiology, and adult and pediatric infectious disease specialties. Recommendations for diagnosis, laboratory investigation, and empiric antimicrobial and adjunctive therapy were developed.
Interobserver Variability in the Interpretation of Colon Manometry Studies in Children
Authors: Sood Manu R. , Mousa Hayat , Tipnis Neel , Di Lorenzo Carlo , Werlin Steven , Fernandez Sergio , Liem Olivia , Simpson Pippa , Rudolph Colin 
Published: March 2012

ABSTRACTObjectives:The aim of the present study was to evaluate the variability in interpretation of colon manometry (CM) in children.Methods:Fifty‐seven colon motility studies were independently reviewed by 5 observers. Each observer was required to report on the colonic motility during fasting, after administration of a meal, and after bisacodyl stimulation. They were also asked to comment whether CM study was normal or abnormal and whether in their opinion the postprandial recording provided clinically useful information.Results:The median (range) agreement regarding the presence of high‐amplitude propagating contractions (HAPC) was 83% (80%–92%). The interpretation of gastrocolonic response produced the most inconsistent results with median (range) agreemnet of 64% (53%–95%). The postprandial period was reported to be useful in only 3% to 24% of the studies. The median (range) agreement regarding the overall interpretation of the study being either normal or abnormal was 87% (83%–90%).Conclusions:The most easily recognizable contraction pattern during CM is the high‐amplitude propagating contractions. Visual interpretation of the gastrocolonic response produces the most inconsistent results and maximum variability. Abbreviated CM studies without the postprandial period or routine calculation of the motility index to evaluate gastrocolonic response can help make colon manometries more objective and reliable.
Next‐generation small RNA sequencing for microRNAs profiling in Apis mellifera: comparison between nurses and foragers
Authors: Liu F. , Peng W. , Li Z. , Li W. , Li L. , Pan J. , Zhang S. , Miao Y. , Chen S. , Su S. 
Published: March 2012

AbstractMicroRNAs (miRNAs) are endogenous small non‐coding RNAs regulating gene expression in animals and plants. To find some differentially expressed miRNAs that may be associated with age‐dependent behavioural changes in honey bees (Apis mellifera), we applied next‐generation high‐throughput sequencing technology to detect small RNAs in nurses and foragers. Our results showed that both nurses and foragers had a complicated small RNA population, and the length of small RNAs varied, 22 nucleotides being the predominant length. Combining deep sequencing and bioinformatic analysis, we discovered that nine known miRNAs were significantly different between nurses and foragers (P < 0.01; absolute value of fold‐change ≥1). Some of their target genes were related to neural function. Moreover, 67 novel miRNAs were identified in nurses and foragers. Ame‐miR‐31a and ame‐miR‐13b were further validated using quantitative reverse‐transcription PCR assays. The present study provides new information on the miRNA abundance of honey bees, and enhances our understanding of miRNA function in the regulation of honey bee development.
Strigolactone analogues induce suicidal seed germination of Striga spp. in soil
Authors: KGOSI R L , ZWANENBURG B , MWAKABOKO A S , MURDOCH A J 
Published: March 2012

Kgosi RL, Zwanenburg B, Mwakaboko AS & Murdoch AJ (2012). Strigolactone analogues induce suicidal seed germination of Striga spp. in soil. Weed Research52, 197–203.SummaryStriga hermonthica and Striga asiatica are obligate root parasites that cause serious problems in the production of staple cereal crops in Africa. Because of the high levels of infestation, there is an urgent need to control these weeds. A potentially useful control option is depletion of the soil seed bank by suicidal germination, which involves germination of the seeds in the absence of host plants. Suicidal germination is often mentioned in the literature, but not considered realistic, because of the alleged untimely decomposition of the stimulants in the soil, despite the fact that some encouraging results were reported around 1980. The alleged instability has prevented active research in this direction for the past 20–25 years. Five newly designed synthetic germination stimulants were investigated as candidates for suicidal germination. An important issue is the persistence of these stimulants in soil. Packets with Striga spp. seeds were put in pots with soil and then treated with aqueous solutions of the stimulants. All five compounds induced germination under these conditions, with percentages varying between 18% and 98% depending on stimulant and species. There were no noticeable signs of decomposition of the stimulants. The best performing stimulant is derived from 1‐tetralone. We conclude that synthetic strigolactones analogues have excellent prospects for use in combating parasitic weeds. Further testing will be needed to evaluate whether such prospects can be realised in the field.