bluuebunny/crossref_metadata_2025 huggingface dataset:
Intracrystalline nucleation during the post‐garnet transformation under large overpressure conditions in deep subducting slabs
Authors: Nishi Masayuki , Irifune Tetsuo , Ohfuji Hiroaki , Tange Yoshinori
Published: November 2012

The mechanism of the post‐garnet transformation in natural single‐crystalline pyropic garnet has been examined under large overpressure conditions of ∼31–43 GPa using the multianvil apparatus with sintered diamond anvils. Intracrystalline nucleation was found to be dominant above 35–38 GPa, while only grain‐boundary nucleation is responsible at lower pressures. In addition, natural pyropic garnet transformed to a single phase of perovskite without decomposing to multiple phases above 38 GPa. Both intracrystalline nucleation and polymorphic growth of the post‐garnet transformation under large overpressure conditions would strongly enhance the transformation kinetics. Consequently, the post‐garnet transformation may pwroceed rapidly in the subducting slab at depths near ∼950 km, which would cause substantial rheological weakening of the subducting slab. The metastable post‐garnet transformation may also cause the seismic discontinuities at a depth of 900–1080 km depth, which is indeed observed beneath some subduction zones.
WITHDRAWN: Compositional Effects in Titan's Thermospheric Gravity Waves
Authors: Cui J. , Lian Y. , Müller‐Wodarg I. C. F.
Published: November 2012

In Titan's upper atmosphere, the density profiles of several constituents (N2, CH4, H2 and 29N2) as measured by the Cassini Ion Neutral Mass Spectrometer (INMS) show periodical structures which we interpret as internal gravity waves. Compositional effects are frequently seen in the data, in which the wave structures in different constituents show different amplitudes and phase angles. We use a simple linearized wave perturbation theory to explain the observations, emphasizing their role as a useful diagnostic of the basic wave parameters. For the T39 flyby, the data‐model comparison constrains typical wavelength to be ~ 350 km, typical wave period to be ~ 64 min, and the direction of wave energy propagation to be primarily vertical. Our calculations also illustrate that wave‐induced diffusion is important for CH4 and H2.
Interaction between volcanic plumes and wind during the 2010 Eyjafjallajökull eruption, Iceland
Authors: Woodhouse M. J. , Hogg A. J. , Phillips J. C. , Sparks R. S. J.
Published: November 2012

Estimates of volcanic source mass flux, currently deduced from observations of plume height, are crucial for ash dispersion models for aviation and population hazard. This study addresses the role of the atmospheric wind in determining the height at which volcanic plumes spread in the atmosphere and the relationship between source mass flux and plume height in a wind field. We present a predictive model of volcanic plumes that describes the bending over of the plume trajectory in a crosswind and show that model predictions are in accord with a dataset of historic eruptions if the profile of atmospheric wind shear is described. The wind restricts the rise height of volcanic plumes such that obtaining equivalent rise heights for a plume in a windy environment would require an order of magnitude increase in the source mass flux over a plume in a quiescent environment. Our model calculations are used to calibrate a semi‐empirical relationship between the plume height and the source mass flux that explicitly includes the atmospheric wind speed. We demonstrate that the model can account for the variations in plume height observed during the first explosive phase of the 2010 Eyjafjallajökull eruption using independently measured wind speeds and show that changes in the observed plume height are better explained by changing meteorology than abrupt changes in the source mass flux. This study shows that unless the wind is properly accounted for, estimates of the source mass flux during an explosive eruption are likely to be very significant underpredictions of the volcanic source conditions.
Physical characteristics and dynamics of the coastal Latex09 Eddy derived from in situ data and numerical modeling
Authors: Kersalé M. , Petrenko A. A. , Doglioli A. M. , Dekeyser I. , Nencioli F.
Published: November 2012

We investigate the dynamics of a coastal anticyclonic eddy in the western part of the Gulf of Lion (GoL) in the northwestern Mediterranean Sea during the Latex campaign in the summer 2009 (Latex09). The sampling strategy combines sea surface temperature satellite imagery, hull‐mounted acoustic Doppler current profiler data, conductivity‐temperature‐depth casts, and drifter trajectories. Our measurements reveal an anticyclonic eddy (Latex09 eddy) with a diameter of ~23 km and maximum depth of 31 m, centered at 3°34′E, 42°33′N. We use a high resolution, three‐dimensional, primitive equation numerical model to investigate its generation process and evolution. The model is able to reproduce the observed eddy, in particular its size and position. The model results suggest that the Latex09 eddy is induced by a large anticyclonic circulation in the northwestern part of the GoL, pushed and squeezed toward the coast by a meander of the Northern Current. This represents a new generation mechanism that has not been reported before. The post generation dynamics of the eddy is also captured by the model. The collision of the Latex09 eddy with Cape Creus results in a transient structure, which is depicted by the trajectories of two Lagrangian drifters during Latex09. The transient structure and its advection lead to a transfer of mass and vorticity from the GoL to the Catalan shelf, indicating the importance of mesoscale structures in modulating such exchanges in the region.
Remote sensing of salinity from satellite‐derived CDOM in the Changjiang River dominated East China Sea
Authors: Bai Yan , Pan Delu , Cai Wei‐Jun , He Xianqiang , Wang Difeng , Tao Bangyi , Zhu Qiankun
Published: November 2012

Defining highly variable freshwater plume area from space is important for characterizing the dynamics of biogeochemical properties and understanding the effects of climate change and human activities on plume‐related processes. The absorption coefficient of colored dissolved organic matter (aCDOM) from satellite ocean color data can be used to estimate the salinity and thus the plume area in coastal oceans if a robust conservative salinity and aCDOM relationship and an accurate satellite aCDOM algorithm can be established. In this paper, tight relationships between surface water salinity and in situ aCDOM were found during several cruises covering all seasons and the full salinity range in the East China Sea. Thus, a salinity inversion model from aCDOM was developed and validated with an independent data set, in which 73.6% of the data were within the absolute salinity error of ±1 and 87.1% were within ±1.5. Factors influencing the conservative behavior of colored dissolved organic matter are analyzed, with a particular focus on the effect of the phytoplankton‐induced autochthonous colored dissolved organic matter. In addition, several satellite aCDOM algorithms were compared and validated with our in situ data. Monthly satellite‐derived salinity images were mapped in August from 2008 to 2010 and showed the significant interannual variability in the plume coverage. This study demonstrated that the salinity derived from satellite‐derived aCDOM can provide a reliable and good synoptic view of the plume area, and help with biogeochemical studies, in particular, those properties related to the interannual variability of plume coverage, although the development of a localized satellite algorithm of aCDOM is still desirable.
Global transients in ultraviolet and red‐infrared ranges from data of Universitetsky‐Tatiana‐2 satellite
Authors: Garipov G. K. , Khrenov B. A. , Klimov P. A. , Klimenko V. V. , Mareev E. A. , Martines O. , Mendoza E. , Morozenko V. S. , Panasyuk M. I. , Park I. H. , Ponce E. , Rivera L. , Salazar H. , Tulupov V. I. , Vedenkin N. N. , Yashin I. V.
Published: November 2012

Light detectors sensitive to wavelength ranges 240–400 nm and beyond 610 nm (which we refer to, for simplicity, as the UV and Red bands) on board Universitetsky‐Tatiana‐2 satellite have detected transient flashes in the atmosphere of duration 1–128 ms. Measured ratio of the number of Red photons to the number of UV photons indicates that source of transient radiation is at high atmosphere altitude (>50 km). Distribution of events with various photon numbers Qa in the atmosphere found to be different for “luminous” events Qa = 1023 – 1026 (with exponent of differential distribution –2.2) and for “faint” events Qa = 1021 – 1023 (with exponent − 0.97). Luminous event parameters (atmosphere altitude, energy released to radiation, and temporal profiles) are similar to observed elsewhere parameters of transient luminous events (TLE) of elves, sprites, halo, and gigantic blue jets types. Global map of luminous events demonstrates concentration to equatorial zones (latitudes 30°N to 30°S) above continents. Faint events (with number of photons Qa = 1020 – 5⋅ 1021) are distributed more uniformly over latitudes and longitudes. Phenomenon of series of transients registered every minute along satellite orbit (from 3 to 16 transients in one series) was observed. Most TLE‐type events belonged to series. Single transients are in average fainter than serial ones. Some transients belonging to series occurs far away of thunderstorm regions. Origin of faint single transients is not clear; several hypothetical models of their production are discussed.
Comparison of TRMM precipitation radar and microwave imager rainfall retrievals in tropical cyclone inner cores and rainbands
Authors: Zagrodnik Joseph P. , Jiang Haiyan
Published: November 2012

Tropical Rainfall Measuring Mission (TRMM) rainfall retrieval algorithms are evaluated in tropical cyclone (TC) inner cores (IC), inner bands (IB), and outer rainbands (OB). In total, 1329 IC, 2149 IB, and 4627 OB storm regions are analyzed using data from a 12‐year TRMM Tropical Cyclone Precipitation Feature (TCPF) database containing 1013 TCs viewed from December 1997 to December 2009. Attention is focused on the difference between the Precipitation Radar (PR) 2A25 and the TRMM Microwave Imager (TMI) 2A12 rainfall algorithms. The PR 2A25 produces larger mean rain rates than the TMI 2A12 in inner cores and inner bands, with the greatest difference occurring in hurricanes. This discrepancy is caused mostly by the TMI 2A12 significantly underestimating regions of moderate to heavy rain >15 mm hour−1 or when the PR reflectivity is greater than 30 dBZ. The TMI 2A12 rain rates are most closely related to the percentage coverage of 85 GHz polarization‐corrected brightness temperature (PCT) <225 K in the IC and 85 GHz PCT <250 K in the IB and OB. These convective parameters are good predictors of the mean TMI 2A12 rain rate, but significant ice scattering is not always present in areas of heavy rain that are often widespread in TC inner regions. As a result, the TMI 2A12 algorithm may poorly measure the rain rate, particularly in the inner core of hurricanes.
Comparison of a photochemical model with observations of mesospheric hydroxyl and ozone
Authors: Siskind David E. , Stevens Michael H. , Englert Christoph R. , Mlynczak M. G.
Published: November 2012

We present a comparison of a photochemical model with mesospheric hydroxyl (OH) data from the Spatial Heterodyne Imager for Mesospheric Radicals (SHIMMER) and mesospheric ozone (O3) data from the Sounding of the Atmosphere with Broadband Emission Radiometry (SABER). Although SHIMMER and SABER do not measure the atmosphere coincidently, by sampling the photochemical model at the appropriate local time of each measurement, an effective concurrent test of mesospheric odd oxygen and odd hydrogen theory can be achieved. Consistent with previous, more limited analyses of SHIMMER data, we find no evidence of a systematic model overprediction of mesospheric OH. However, at 80 km, the standard chemical scheme shows a model deficit in the morning  hours and a dramatic model excess in the late afternoon. Using a higher rate coefficient for the H + O2 + M → HO2 + M reaction ameliorates this problem. Such a higher rate is consistent with the only reported laboratory measurements at the low temperatures appropriate to the mesosphere. Regarding the SABER ozone, the model significantly underpredicts the data. Some of this could be explained by a previously reported, systematic high bias to the SABER ozone, and comparisons of our model with Microwave Limb Sounder data support that suggestion. Nonetheless, a persistent model ozone deficit remains. Since the model agreement with SHIMMER OH is generally very good, this model ozone deficit is unlikely to be due to a mischaracterization of mesospheric HOx.
Intercomparison of bias‐correction methods for monthly temperature and precipitation simulated by multiple climate models
Authors: Watanabe Satoshi , Kanae Shinjiro , Seto Shinta , Yeh Pat J.‐F. , Hirabayashi Yukiko , Oki Taikan
Published: November 2012

Bias‐correction methods applied to monthly temperature and precipitation data simulated by multiple General Circulation Models (GCMs) are evaluated in this study. Although various methods have been proposed recently, an intercomparison among them using multiple GCM simulations has seldom been reported. Moreover, no previous methods have addressed the issue how to adequately deal with the changes of the statistics of bias‐corrected variables from the historical to future simulations. In this study, a new method which conserves the changes of mean and standard deviation of the uncorrected model simulation data is proposed, and then five previous bias‐correction methods as well as the proposed new method are intercompared by applying them to monthly temperature and precipitation data simulated from 12 GCMs in the Coupled Model Intercomparison Project (CMIP3) archives. Parameters of each method are calibrated by using 1948–1972 observed data and validated in the 1974–1998 period. These methods are then applied to the GCM future simulations (2073–2097) and the bias‐corrected data are intercompared. For the historical simulations, negligible difference can be found between observed and bias‐corrected data. However, the differences in future simulations are large dependent on the characteristics of each method. The new method successfully conserves the changes in the mean, standard deviation and the coefficient of variation before and after bias‐correction. The differences of bias‐corrected data among methods are discussed according to their respective characteristics. Importantly, this study classifies available correction methods into two distinct categories, and articulates important features for each of them.
Variability of the surface radiation budget over the United States from 1996 through 2011 from high‐quality measurements
Authors: Augustine John A. , Dutton Ellsworth G.
Published: November 2012

Sixteen years of high‐quality surface radiation budget (SRB) measurements over seven U.S. stations are summarized. The network average total surface net radiation increases by +8.2 Wm−2 per decade from 1996 to 2011. A significant upward trend in downwelling shortwave (SW‐down) of +6.6 Wm−2 per decade dominates the total surface net radiation signal. This SW brightening is attributed to a decrease in cloud coverage, and aerosols have only a minor effect. Increasing downwelling longwave (LW‐down) of +1.5 Wm−2 per decade and decreasing upwelling LW (LW‐up) of −0.9 Wm−2 per decade produce a +2.3 Wm−2 per decade increase in surface net‐LW, which dwarfs the expected contribution to LW‐down from the 30 ppm increase of CO2 during the analysis period. The dramatic surface net radiation excess should have stimulated surface energy fluxes, but, oddly, the temperature trend is flat, and specific humidity decreases. The enigmatic nature of LW‐down, temperature, and moisture may be a chaotic result of their large interannual variations. Interannual variation of the El Niño/Southern Oscillation (ENSO) ONI index is shown to be moderately correlated with temperature, moisture, and LW‐down. Thus, circulations associated with ENSO events may be responsible for manipulating (e.g., by advection or convection) the excess surface energy available from the SRB increase. It is clear that continued monitoring is necessary to separate the SRB's response to long‐term climate processes from natural variability and that collocated surface energy flux measurements at the SRB stations would be beneficial.
Bankfull hydraulic geometry of submarine channels created by turbidity currents: Relations between bankfull channel characteristics and formative flow discharge
Authors: Konsoer Kory , Zinger Jessica , Parker Gary
Published: November 2012

Detailed bathymetric surveys of the seafloor have enabled the identification and analysis of submarine channels worldwide. Previous authors have remarked on the morphologic similarity of submarine channels and rivers, and have identified a number of similarities and differences in processes of flow and sedimentation. In this study, we compare the width, depth, and slope of 177 submarine channel cross‐sections to that of 231 river cross‐sections. The results indicate that submarine channels have cross‐sectional dimensions that can exceed the dimensions of the largest rivers on earth by an order of magnitude. For rivers and submarine channels with similar width or depth, the slope of submarine channels can be up to two orders of magnitude greater than the slope of rivers. An analysis of trends in driving force vs. channel size suggests that a reasonable estimate of the volumetric sediment concentration of channelized turbidity currents lies in the range C = 0.2% to 0.6%. Bankfull turbidity current velocities are estimated using this range in concentration. Friction coefficients are based on values identified for large rivers and a modified Chezy equation. These velocities are then used in a classic hydraulic geometry analysis of the submarine channels, which shows that submarine channels and rivers follow similar power law trends in width, depth, and velocity as functions of bankfull discharge.
Evolution of drainage system morphology at a land‐terminating Greenlandic outlet glacier
Authors: Cowton Tom , Nienow Peter , Sole Andrew , Wadham Jemma , Lis Greg , Bartholomew Ian , Mair Doug , Chandler Dave
Published: November 2012

The influence of meltwater on the dynamics and geomorphic impact of the Greenland Ice Sheet is strongly controlled by the morphology of the ice sheet's drainage system. However, this system and its evolution through the melt season remain poorly understood. Here we present the results of an intensive programme of dye tracing experiments undertaken along the lower 14 km of a land‐terminating Greenlandic outlet glacier over a period of four months during the 2010 melt season. These data are interpreted in conjunction with observations of proglacial discharge, englacial water storage, surface melt rates and ice velocity to produce a detailed picture of the changing hydrology of the glacier. Following the onset of melt in the spring, inputs to the drainage system regularly exceed outputs, causing the englacial water level to rise to the ice sheet surface. During this time there is a rapid transition from distributed to channelized drainage in those parts of the drainage system closed by ice deformation over winter. As the melt season progresses, channel efficiency increases and englacial storage and ice velocity decrease. High‐velocity events continue to be observed following the channelization of the drainage system however, indicating that hydrological forcing of ice velocity occurs despite the existence of channels during periods when meltwater inputs exceed the capacity of the subglacial drainage system.
Root niche separation can explain avoidance of seasonal drought stress and vulnerability of overstory trees to extended drought in a mature Amazonian forest
Authors: Ivanov Valeriy Y. , Hutyra Lucy R. , Wofsy Steven C. , Munger J. William , Saleska Scott R. , de Oliveira Raimundo C. , de Camargo Plínio B.
Published: November 2012

Large areas of Amazonian evergreen forest experience seasonal droughts extending for three or more months, yet show maximum rates of photosynthesis and evapotranspiration during dry intervals. This apparent resilience is belied by disproportionate mortality of the large trees in manipulations that reduce wet season rainfall, occurring after 2–3 years of treatment. The goal of this study is to characterize the mechanisms that produce these contrasting ecosystem responses. A mechanistic model is developed based on the ecohydrological framework of TIN (Triangulated Irregular Network)‐based Real Time Integrated Basin Simulator + Vegetation Generator for Interactive Evolution (tRIBS+VEGGIE). The model is used to test the roles of deep roots and soil capillary flux to provide water to the forest during the dry season. Also examined is the importance of “root niche separation,” in which roots of overstory trees extend to depth, where during the dry season they use water stored from wet season precipitation, while roots of understory trees are concentrated in shallow layers that access dry season precipitation directly. Observational data from the Tapajós National Forest, Brazil, were used as meteorological forcing and provided comprehensive observational constraints on the model. Results strongly suggest that deep roots with root niche separation adaptations explain both the observed resilience during seasonal drought and the vulnerability of canopy‐dominant trees to extended deficits of wet season rainfall. These mechanisms appear to provide an adaptive strategy that enhances productivity of the largest trees in the face of their disproportionate heat loads and water demand in the dry season. A sensitivity analysis exploring how wet season rainfall affects the stability of the rainforest system is presented.
Estimation of macrodispersion in 2‐D highly heterogeneous porous media using the Eulerian‐Lagrangian localized adjoint method
Authors: Ramasomanana Fanilo , Younes Anis , Ackerer Philippe
Published: November 2012

Key Points

Validation of first and higher order stochastic theories

Effects of local dispersion on macrodispersion

Required travel distance to reach Fickian regime
Monocyte‐derived macrophages do not explain susceptibility to pulmonary non‐tuberculous mycobacterial disease
Authors: de Jong Emma , Lim Andrew , Waterer Grant , Price Patricia
Published: November 2012

Pulmonary infections with non‐tuberculous mycobacteria (NTM) affect a subset of older individuals (mostly women) with no known immunological defects. As NTMs are intracellular pathogens, it is important to establish whether NTM disease is associated with defective production of Th1 cytokines or poor responses by host macrophage/monocytes. We have shown that patients display vigorous production of interferon gamma (IFNγ) when CD4 T cells are stimulated with mycobacterial antigens. This implicated the macrophage response to IFNγ. Blood monocytes are poorly representative of lung macrophages, so monocyte‐derived macrophages (MDMs) were created and then stimulated with lipomannan (a Toll‐like receptor (TLR)2 agonist), lipopolysaccharide (LPS; a TLR4 agonist) or recombinant human IFNγ. MDMs from NTM patients, their offspring and healthy donors expressed similar amounts of IFNγR1, and cellular responses to IFNγ were similar, so there is no evidence of a genetic defect in this pathway. MDMs from NTM patients produced less interleukin‐6 in response to LPS (P<0.01) than cells from controls, but other cytokine responses were normal. This warrants further study.
Early Brain Injury Alters the Blood–Brain Barrier Phenotype in Parallel with β-Amyloid and Cognitive Changes in Adulthood
Authors: Pop Viorela , Sorensen Dane W , Kamper Joel E , Ajao David O , Murphy M Paul , Head Elizabeth , Hartman Richard E , Badaut Jérôme
Published: November 2012

Clinical studies suggest that traumatic brain injury (TBI) hastens cognitive decline and development of neuropathology resembling brain aging. Blood–brain barrier (BBB) disruption following TBI may contribute to the aging process by deregulating substance exchange between the brain and blood. We evaluated the effect of juvenile TBI (jTBI) on these processes by examining long-term alterations of BBB proteins, β-amyloid (Aβ) neuropathology, and cognitive changes. A controlled cortical impact was delivered to the parietal cortex of male rats at postnatal day 17, with behavioral studies and brain tissue evaluation at 60 days post-injury (dpi). Immunoglobulin G extravasation was unchanged, and jTBI animals had higher levels of tight-junction protein claudin 5 versus shams, suggesting the absence of BBB disruption. However, decreased P-glycoprotein (P-gp) on cortical blood vessels indicates modifications of BBB properties. In parallel, we observed higher levels of endogenous rodent Aβ in several brain regions of the jTBI group versus shams. In addition at 60 dpi, jTBI animals displayed systematic search strategies rather than relying on spatial memory during the water maze. Together, these alterations to the BBB phenotype after jTBI may contribute to the accumulation of toxic products, which in turn may induce cognitive differences and ultimately accelerate brain aging.
Glibenclamide Enhances Neurogenesis and Improves Long-Term Functional Recovery after Transient Focal Cerebral Ischemia
Authors: Ortega Francisco J , Jolkkonen Jukka , Mahy Nicole , Rodríguez Manuel J
Published: November 2012

Glibenclamide is neuroprotective against cerebral ischemia in rats. We studied whether glibenclamide enhances long-term brain repair and improves behavioral recovery after stroke. Adult male Wistar rats were subjected to transient middle cerebral artery occlusion (MCAO) for 90 minutes. A low dose of glibenclamide (total 0.6 μg) was administered intravenously 6, 12, and 24 hours after reperfusion. We assessed behavioral outcome during a 30-day follow-up and animals were perfused for histological evaluation. In vitro specific binding of glibenclamide to microglia increased after pro-inflammatory stimuli. In vivo glibenclamide was associated with increased migration of doublecortin-positive cells in the striatum toward the ischemic lesion 72 hours after MCAO, and reactive microglia expressed sulfonylurea receptor 1 (SUR1) and Kir6.2 in the medial striatum. One month after MCAO, glibenclamide was also associated with increased number of NeuN-positive and 5-bromo-2-deoxyuridine-positive neurons in the cortex and hippocampus, and enhanced angiogenesis in the hippocampus. Consequently, glibenclamide-treated MCAO rats showed improved performance in the limb-placing test on postoperative days 22 to 29, and in the cylinder and water-maze test on postoperative day 29. Therefore, acute blockade of SUR1 by glibenclamide enhanced long-term brain repair in MCAO rats, which was associated with improved behavioral outcome.
Higher Coated-Platelet Levels are Associated with Stroke Recurrence following Nonlacunar Brain Infarction
Authors: Prodan Calin I , Stoner Julie A , Cowan Linda D , Dale George L
Published: November 2012

Coated-platelets are procoagulant platelets observed upon dual-agonist stimulation with collagen and thrombin. Coated-platelet levels are elevated in patients with nonlacunar (large-vessel) ischemic stroke and decreased in patients with spontaneous intracerebral hemorrhage as compared with controls. The purpose of this study was to investigate a possible relationship between coated-platelet levels and stroke recurrence in patients with nonlacunar ischemic stroke. We assayed coated-platelet levels in 190 consecutive patients with nonlacunar stroke who were followed for up to 12 months; 20 subjects experienced recurrent stroke. Subjects were categorized into tertiles of coated-platelet levels. The distributions of time-to-recurrent stroke were estimated for each tertile using cumulative incidence curves and compared statistically using a log-rank test. The cumulative incidence of recurrent stroke at 12 months differed among the coated-platelet tertiles: 2% for the first tertile (lowest coated-platelet levels), 18% for the second tertile, and 17% for the third tertile (overall log-rank test, P = 0.019). These data suggest that higher levels of coated-platelets, measured shortly after a nonlacunar stroke, are associated with an increased incidence of stroke recurrence. This observation offers an additional tool for identifying patients at highest risk for stroke recurrence following a nonlacunar (large-vessel) infarct.
Predicting Nonlinear Changes in Bone Mineral Density Over Time Using a Multiscale Systems Pharmacology Model
Authors: Peterson MC , Riggs MM
Published: November 2012

A mathematical model component that extends an existing physiologically based multiscale systems pharmacology model (MSPM) of calcium and bone homeostasis was developed, enabling prediction of nonlinear changes in lumbar spine bone mineral density (LSBMD). Data for denosumab, a monoclonal antibody osteoporosis treatment, dosed at several levels and regimens, was used for fitting the BMD component. Bone marker and LSBMD data extracted from the literature described on/off‐treatment effects of denosumab over 48 months [Miller, P.D. et al. Effect of denosumab on bone density and turnover in postmenopausal women with low bone mass after long‐term continued, discontinued, and restarting of therapy: a randomized blinded phase 2 clinical trial. Bone 43, 222–229 (2008)]. An indirect model linking bone markers to LSBMD was embedded in the existing MSPM, reasonably predicting nonlinear increases in LSBMD during treatment (24 months); LSBMD declines following discontinuation and increases upon treatment reinstitution. This study demonstrates the utility of MSPM extension to describe a phenomena of interest not originally in a model, and the ability of this updated MSPM to predict nonlinear longitudinal changes in the clinically relevant endpoint, LSBMD, with denosumab treatment.

CPT: Pharmacometrics & Systems Pharmacology (2012) 1, e14; doi:10.1038/psp.2012.15; advance online publication 14 November 2012
Assessment of Alcohol Use Patterns among Spanish-Speaking Patients
Authors: Lotfipour Shahram , Cisneros Victor , Anderson Craig L. , Roumani Samer , Hoonpongsimanont Wirachin , Weiss Jie , Chakravarthy Bharath , Dykzeul Brad , Vaca Federico
Published: November 2012

Objective: The objective of this study was to assess drinking patterns of Spanish-speaking patients using a bilingual computerized alcohol screening and brief intervention (CASI) tablet computer equipped with the Alcohol Use Disorders Identification Test (AUDIT). Methods: This retrospective study was conducted in a tertiary university hospital emergency department (ED) between 2006 and 2010. Data from 1816 Spanish-speaking ED patients were analyzed using descriptive statistics, the chi-square test for independence, and the Kruskal-Wallis rank sum test for comparisons using quantitative variables. Results: Overall, 15% of Spanish-speaking patients were at-risk drinkers, and 5% had an AUDIT score consistent with alcohol dependency (≥20). A higher percentage of Spanish-speaking males than females were at-risk drinkers or likely dependent. Spanish-speaking males exhibited higher frequency of drinking days per week and higher number of drinks per day compared with females. Among older patients, nondrinking behavior increased and at-risk drinkers decreased. The majority of males and females were ready to change their behavior after the CASI intervention; 61% and 69%, respectively, scored 8–10. Conclusions: This study indicated that CASI was an effective tool for detecting at-risk and likely dependent drinking behavior in Spanish-speaking ED patients. The majority of patients were ready to change their drinking behavior. More alcohol screening and brief intervention tools should be tested and become readily accessible for Spanish-speaking patients.
Magnetic characterization of thin Co50Fe50 films by magnetooptic Kerr effect
Authors: Kuschel T , Hamrle J , Pištora J , Saito K , Bosu S , Sakuraba Y , Takanashi K , Wollschläger J
Published: November 2012

Magnetic properties of thin Co50Fe50 films on MgO(0 0 1) prepared with different annealing temperatures between room temperature and 300 °C are studied by vectorial magnetometry based on the magnetooptic Kerr effect. Independent from the annealing, the Co50Fe50 films reveal some similar magnetic properties, e.g. no quadratic magnetooptic Kerr effect and a magnetic reversal process which is completely in-plane with magnetic easy axes in Co50Fe50〈1 1 0〉 directions. If the alignment of the external magnetic field is close to the magnetic hard axes, incoherent rotation of magnetic moments between saturation and remanence occurs instead of coherent rotation as for the other directions. If the magnitude of the magnetization is polar plotted with respect to the azimuthal magnetization angle, sequential switching of magnetic moments from one magnetic easy axis to another can be proved by the course of the magnetization. Here, a two-domain switching process can be distinguished from a four-domain switching process generated by the incoherent rotation between saturation and remanence. Furthermore, both the uniaxial magnetic anisotropy constants and the domain wall pinning energies are determined from the magnetic switching fields using the Stoner–Wohlfarth model while the cubic magnetic anisotropy constants are obtained from fitting the magnetization curves. The domain wall pinning energies obtained from these analyses decrease with increasing annealing temperature due to fewer defects in the film. The cubic magnetic anisotropy also decreases slightly which can be attributed to relaxation of the crystal lattice for increasing annealing temperature due to a small change of spin–orbit coupling. Compared with the cubic magnetic anisotropy the uniaxial magnetic anisotropy is very small. This may be attributed to the reduction of strain in the film caused by a buffer stack Cr/Au/Cr between the Co50Fe50 film and MgO(0 0 1).
Simulation analysis of triboplasma generation using the particle-in-cell/Monte Carlo collision (PIC/MCC) method
Authors: Nakayama Keiji , Tanaka Masaaki
Published: November 2012

Previously, a microplasma was discovered in the rear gap of a sliding contact. This plasma is called a ‘triboplasma’, the behaviour of which obeys the Paschen law in a gas discharge. The generation of the triboplasma has been explained to be generated by discharging of ambient air due to the intense electric field caused by tribocharging, based on the experimental findings.

In this report, the mechanism of triboplasma generation is theoretically analysed using the particle-in-cell/Monte Carlo collision (PIC/MCC) simulation method for the triboplasma generated in the tribosystem, where a diamond pin slides against a sapphire disc in ambient air. Two-dimensional sideward density distributions of the electrons,

ions and

ions in the rear gap of the sliding contact are obtained theoretically by the PIC/MCC method. These calculated particle distributions coincided well with the triboplasma distributions experimentally observed. The previously proposed triboplasma generation due to gas discharging is verified theoretically using the PIC/MCC simulation method.
Interface properties of GaInP/Ge hetero-structure sub-cells of multi-junction solar cells
Authors: Gudovskikh A S , Zelentsov K S , Kalyuzhnyy N A , Evstropov V V , Lantratov V M , Mintairov S A
Published: November 2012

The interface properties of the GaInP/Ge hetero-structure solar cells were studied. It was found that an undesirable potential barrier for the majority carriers could occur at the n-GaInP/n-Ge hetero-interface during the growth of multi-junction solar cells. The potential barrier at the GaInP/Ge interface leads to S-shape behaviour of I–V curves at low temperatures, which was observed either for the single junctions or for the multi-junction solar cells containing the n-GaInP/n-Ge interface. The values of the effective barrier height and width as 0.12 ± 0.05 eV and 45–55 nm, respectively, were estimated by admittance spectroscopy and by C–V profiling measurements.
On the local extension of Killing vector-fields in Ricci flat manifolds
Authors: Ionescu Alexandru , Klainerman Sergiu
Published: November 2012

We revisit the extension problem for Killing vector-fields in smooth Ricci flat manifolds, and its relevance to the black hole rigidity problem. We prove both a stronger version of the main local extension result established earlier, as well as two types of results concerning non-extendibility. In particular, we show that one can find local, stationary, vacuum extensions of a Kerr solutionK(m,a)\mathcal {K}(m,a),0>a>m0>a>m, in a future neighborhood of any pointppof the past horizon lying outside both the bifurcation sphere and the axis of symmetry, which admit no extension of the Hawking vector-field ofK(m,a)\mathcal {K}(m,a). This result illustrates one of the major difficulties one faces in trying to extend Hawking’s rigidity result to the more realistic setting of smooth stationary solutions of the Einstein vacuum equations; unlike in the analytic situation, one cannot hope to construct an additional symmetry of stationary solutions (as in Hawking’s Rigidity Theorem) by relying only on local information.
Characterization of Waxy Rice Cakes (Mochi) with Rapid Hardening Quality by Instrumental and Sensory Methods
Authors: Sasaki Tomoko , Hayakawa Fumiyo , Suzuki Yasuhiro , Suzuki Keitaro , Okamoto Kazuyuki , Kohyama Kaoru
Published: November 2012

The textural properties of cooked waxy rice cakes made from four waxy rice varieties including the unique varieties Kantomochi 172 (K172) and BC3 with the property of rapid hardening were analyzed by instrumental and sensory methods. For the instrumental analysis, a compression test, adhesiveness test, and tensile test were conducted. The waxy rice cakes made from K172 and BC3 showed significantly higher compressive force and resistance to break under tensile load. Significant difference in amylopectin chain‐length distribution was observed between each variety, and this difference strongly reflected the hardness of waxy rice cakes. The peak area ratio of amylopectin branch chains with 6–12 degrees of polymerization negatively correlated with the compressive force required for 50 and 80% strain. Sensory evaluation showed that the waxy rice cakes made from these varieties had a significantly harder, less stretchable, less smooth surface, whereas the scores for adhesiveness and ease to cut off (hagire) were preferable to those for other rice varieties.
The 2009 Late Blight Pandemic in the Eastern United States – Causes and Results
Authors: Fry W. E. , McGrath M. T. , Seaman A. , Zitter T. A. , McLeod A. , Danies G. , Small I. M. , Myers K. , Everts K. , Gevens A. J. , Gugino B. K. , Johnson S. B. , Judelson H. , Ristaino J. , Roberts P. , Secor G. , Seebold K. , Snover-Clift K. , Wyenandt A. , Grünwald N. J. , Smart C. D.
Published: November 2012

The tomato late blight pandemic of 2009 made late blight into a household term in much of the eastern United States. Many home gardeners and many organic producers lost most if not all of their tomato crop, and their experiences were reported in the mainstream press. Some CSAs (Community Supported Agriculture) could not provide tomatoes to their members. In response, many questions emerged: How did it happen? What was unusual about this event compared to previous late blight epidemics? What is the current situation in 2012 and what can be done? It's easiest to answer these questions, and to understand the recent epidemics of late blight, if one knows a bit of the history of the disease and the biology of the causal agent, Phytophthora infestans.
Closed-loop control of zebrafish response using a bioinspired robotic-fish in a preference test
Authors: Kopman Vladislav , Laut Jeffrey , Polverino Giovanni , Porfiri Maurizio
Published: November 2012

In this paper, we study the response of zebrafish to a robotic-fish whose morphology and colour pattern are inspired by zebrafish. Experiments are conducted in a three-chambered instrumented water tank where a robotic-fish is juxtaposed with an empty compartment, and the preference of live subjects is scored as the mean time spent in the vicinity of the tank's two lateral sides. The tail-beating of the robotic-fish is controlled in real-time based on feedback from fish motion to explore a spectrum of closed-loop systems, including proportional and integral controllers. Closed-loop control systems are complemented by open-loop strategies, wherein the tail-beat of the robotic-fish is independent of the fish motion. The preference space and the locomotory patterns of fish for each experimental condition are analysed and compared to understand the influence of real-time closed-loop control on zebrafish response. The results of this study show that zebrafish respond differently to the pattern of tail-beating motion executed by the robotic-fish. Specifically, the preference and behaviour of zebrafish depend on whether the robotic-fish tail-beating frequency is controlled as a function of fish motion and how such closed-loop control is implemented.
Implications of spatially heterogeneous vaccination coverage for the risk of congenital rubella syndrome in South Africa
Authors: Metcalf C. J. E. , Cohen C. , Lessler J. , McAnerney J. M. , Ntshoe G. M. , Puren A. , Klepac P. , Tatem A. , Grenfell B. T. , Bjørnstad O. N.
Published: November 2012

Rubella is generally a mild childhood disease, but infection during early pregnancy may cause spontaneous abortion or congenital rubella syndrome (CRS), which may entail a variety of birth defects. Since vaccination at levels short of those necessary to achieve eradication may increase the average age of infection, and thus potentially the CRS burden, introduction of the vaccine has been limited to contexts where coverage is high. Recent work suggests that spatial heterogeneity in coverage should also be a focus of concern. Here, we use a detailed dataset from South Africa to explore the implications of heterogeneous vaccination for the burden of CRS, introducing realistic vaccination scenarios based on reported levels of measles vaccine coverage. Our results highlight the potential impact of country-wide reductions of incidence of rubella on the local CRS burdens in districts with small population sizes. However, simulations indicate that if rubella vaccination is introduced with coverage reflecting current estimates for measles coverage in South Africa, the burden of CRS is likely to be reduced overall over a 30 year time horizon by a factor of 3, despite the fact that this coverage is lower than the traditional 80 per cent rule of thumb for vaccine introduction, probably owing to a combination of relatively low birth and transmission rates. We conclude by discussing the likely impact of private-sector vaccination.
The workings of the maximum entropy principle in collective human behaviour
Authors: Hernando A. , Hernando R. , Plastino A. , Plastino A. R.
Published: November 2012

We present an exhaustive study of the rank-distribution of city-population and population-dynamics of the 50 Spanish provinces (more than 8000 municipalities) in a time-window of 15 years (1996–2010). We exhibit compelling evidence regarding how well the MaxEnt principle describes the equilibrium distributions. We show that the microscopic dynamics that governs population growth is the deciding factor that originates the observed macroscopic distributions. The connection between microscopic dynamics and macroscopic distributions is unravelled via MaxEnt.
Levels, Temporal-Spatial Variations, and Sources of Organochlorine Pesticides in Ambient Air of Lake Chaohu, China
Authors: Ouyang Hui-Ling , He Wei , Qin Ning , Kong Xiang-Zhen , Liu Wen-Xiu , He Qi-Shuang , Wang Qing-Mei , Jiang Yu-Jiao , Yang Chen , Yang Bin , Xu Fu-Liu
Published: November 2012

The residual levels of OCPs in the gas phase and particle phase in Lake Chaohu, China, were measured using GC-MS from March 2010 to February 2011. The temporal-spatial variations and sources of OCPs were also analyzed. Twenty types of OCPs were detected in the gas phase with a total concentration of484.8±550.4 pg/m3. Endosulfan, DDTs and chlordane were the primary OCPs in the gas phase. The mean concentration of OCPs in the gas phase was significantly higher in the summer than in the winter. Seventeen types of OCPs were detected in the particle phase with a total concentration of 18.3 ± 26.1 pg/m3. DDTs were major OCPs in the particle phase. The mean concentration of OCPs in the particle phase decreased at first and then increased during the period. The potential source of the HCHs in ambient air of Lake Chaohu might come from recent lindane usage. DDTs mainly came from historical dicofol usage, and an input of DDT was observed in the spring, which may result from the present use of marine paint that contains technical DDT. Endosulfan and chlordane in the air may be due to the present use of technical endosulfan and chlordane.
NaStEP: A Proteinase Inhibitor Essential to Self-Incompatibility and a Positive Regulator of HT-B Stability inNicotiana alataPollen Tubes
Authors: Jiménez-Durán Karina , McClure Bruce , García-Campusano Florencia , Rodríguez-Sotres Rogelio , Cisneros Jesús , Busot Grethel , Cruz-García Felipe
Published: November 2012

In Solanaceae, the self-incompatibility S-RNase and S-locus F-box interactions define self-pollen recognition and rejection in an S-specific manner. This interaction triggers a cascade of events involving other gene products unlinked to the S-locus that are crucial to the self-incompatibility response. To date, two essential pistil-modifier genes, 120K and High Top-Band (HT-B), have been identified in Nicotiana species. However, biochemistry and genetics indicate that additional modifier genes are required. We recently reported a Kunitz-type proteinase inhibitor, named NaStEP (for Nicotiana alata Stigma-Expressed Protein), that is highly expressed in the stigmas of self-incompatible Nicotiana species. Here, we report the proteinase inhibitor activity of NaStEP. NaStEP is taken up by both compatible and incompatible pollen tubes, but its suppression in Nicotiana spp. transgenic plants disrupts S-specific pollen rejection; therefore, NaStEP is a novel pistil-modifier gene. Furthermore, HT-B levels within the pollen tubes are reduced when NaStEP-suppressed pistils are pollinated with either compatible or incompatible pollen. In wild-type self-incompatible N. alata, in contrast, HT-B degradation occurs preferentially in compatible pollinations. Taken together, these data show that the presence of NaStEP is required for the stability of HT-B inside pollen tubes during the rejection response, but the underlying mechanism is currently unknown.