bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facebook Discussion Groups Provide a Robust Worldwide Platform for Free Pathology Education
Authors: Gonzalez Raul S. , Amer Sadiq M. , Yahia Nejib Ben , Costa Felipe D'Almeida , Noatay Manu , Qiao Jian-Hua , Rosado Flavia G. , Rosen Yale , Sedassari Bruno Tavares , Yantiss Rhonda K. , Gardner Jerad M. 
Published: October 2016

Context.—Facebook (Menlo Park, California) is one of many online sites that provide potential educational tools for pathologists. We have each founded Facebook groups dedicated to anatomic pathology, in which members can share cases, ask questions, and contribute to discussions.Objectives.—To report our experiences in founding and maintaining these Facebook groups and to characterize the contributed content.Design.—We circulated a survey among the group founders, then compiled and analyzed the responses.Results.—The groups varied in membership and in the quality of member contribution. Most posts were of pathology cases, although other topics (such as research articles) were also shared. All groups remained active and received posts from users all over the world, although all groups had many noncontributing members and received unwanted messages (which were screened and removed). Most founders were glad they had founded the groups because they provided an opportunity to both teach and learn.Conclusions.—Each analyzed Facebook group had a different character, and some downsides exist, but the groups all provided a no-cost way for pathologists and others across the world to interact online with many colleagues.
Interdecadal Trichodesmium variability in cold North Atlantic waters
Authors: Rivero‐Calle Sara , Del Castillo Carlos E. , Gnanadesikan Anand , Dezfuli Amin , Zaitchik Benjamin , Johns David G. 
Published: October 2016

AbstractStudies of the nitrogen cycle in the ocean generally assume that the distribution of the marine diazotroph, Trichodesmium, is restricted to warm, tropical, and subtropical oligotrophic waters. Here we show evidence that Trichodesmium are widely distributed in the North Atlantic. We report an approximately fivefold increase during the 1980s and 1990s in Trichodesmium presence near the British Isles with respect to the average over the last 50 years. A potential explanation is an increase in the Saharan dust source starting in the 1980s, coupled with changes in North Atlantic winds that opened a pathway for dust transport. Results from a coarse‐resolution model in which winds vary but iron deposition is climatologically fixed suggest frequent nitrogen limitation in the region and reversals of the Portugal current, but it does not simulate the observed changes in Trichodesmium. Our results suggest that Trichodesmium may be capable of growth at temperatures below 20°C and challenge assumptions about their latitudinal distribution. Therefore, we need to reevaluate assumptions about the temperature limitations of Trichodesmium and the dinitrogen (N2) fixation capabilities of extratropical strains, which may have important implications for the global nitrogen budget.
Vertical modeling of the nitrogen cycle in the eastern tropical South Pacific oxygen deficient zone using high‐resolution concentration and isotope measurements
Authors: Peters Brian D. , Babbin Andrew R. , Lettmann Karsten A. , Mordy Calvin W. , Ulloa Osvaldo , Ward Bess B. , Casciotti Karen L. 
Published: October 2016

AbstractMarine oxygen deficient zones (ODZs) have long been identified as sites of fixed nitrogen (N) loss. However, the mechanisms and rates of N loss have been debated, and traditional methods for measuring these rates are labor‐intensive and may miss hot spots in spatially and temporally variable environments. Here we estimate rates of heterotrophic nitrate reduction, heterotrophic nitrite reduction (denitrification), nitrite oxidation, and anaerobic ammonium oxidation (anammox) at a coastal site in the eastern tropical South Pacific (ETSP) ODZ based on high‐resolution concentration and natural abundance stable isotope measurements of nitrate (NO3−) and nitrite (NO2−). These measurements were used to estimate process rates using a two‐step inverse modeling approach. The modeled rates were sensitive to assumed isotope effects for NO3− reduction and NO2− oxidation. Nevertheless, we addressed two questions surrounding the fates of NO2− in the ODZ: (1) Is NO2− being primarily reduced to N2 or oxidized to NO3− in the ODZ? and (2) what are the contributions of anammox and denitrification to NO2− removal? Depth‐integrated rates from the model suggest that 72–88% of the NO2− produced in the ODZ was oxidized back to NO3−, while 12–28% of NO2− was reduced to N2. Furthermore, our model suggested that 36–74% of NO2− loss was due to anammox, with the remainder due to denitrification. These model results generally agreed with previously measured rates, though with a large range of uncertainty, and they provide a long‐term integrated view that compliments incubation experiments to obtain a broader picture of N cycling in ODZs.
Multidecadal wind‐driven shifts in northwest Pacific temperature, salinity, O2, and PO4
Authors: Kwon Eun Young , Kim Young Ho , Park Young‐Gyu , Park Young‐Hyang , Dunne John , Chang Kyung‐Il 
Published: October 2016

AbstractThe North Pacific gyre boundaries are characterized by stark contrasts in physical and biogeochemical properties. Meridional movement of gyre boundaries, influenced by climate change, can therefore exert a large influence not only on marine ecosystems but also on climate. We examine the evidence for wind‐driven southward shifts in subsurface temperature, salinity, PO4, and O2 within the northwest Pacific from the 1950s to the 2000s. Gyre boundary shifts can explain 30–60% of temperature and salinity trends zonally averaged in the northwest Pacific and observed PO4 and O2 trends along the 137°E and 144°E meridians. The close tie between the wind‐driven shifts in gyre boundaries and the tracer distributions is further supported by results from an eddy‐resolving (0.1° × 0.1°) Geophysical Fluid Dynamics Laboratory climate model, suggesting that the physical and biogeochemical properties averaged within the northwest Pacific gyre boundaries closely follow the latitude changes of the zero Sverdrup stream function with lags of 0 to 3 years. The gyre shift effect on tracer distribution is poorly represented in a coarse resolution (1° × 1°) model due partly to poor representations of fronts and eddies. This study suggests that future changes in northwest Pacific PO4 and O2 content may depend not only on ocean temperature and stratification but also on the ocean gyre response to winds.
An effective approach to evaluate GCM simulated diurnal variation of clouds
Authors: Chen Guoxing , Wang Wei‐Chyung 
Published: October 2016

AbstractCloud radiative effects strongly depend on diurnal variations of insolation and cloud radiative properties. In general circulation models (GCMs), even when the daily‐mean cloud properties agree with observations, errors in cloud diurnal cycle can still significantly impact the shortwave radiation and induce model biases. However, this aspect is overlooked in GCM evaluation and intercomparison programs (e.g., Coupled Model Intercomparison Project Phase 5 (CMIP5)), which mainly consider the daily‐mean cloud fraction. This study presents a simple approach of using a diagnostic parameter, the “effective‐daytime cloud fraction” which accounts for the concurrent variation of clouds and insolation, to reveal GCM biases in cloud diurnal variations. The usefulness of the approach is illustrated by the significant biases of cloud diurnal cycle in the Modern‐Era Retrospective analysis for Research and Applications (MERRA) reanalysis when compared with that in the International Satellite Cloud Climatology Project (ISCCP) data. It is thus suggested that the parameter be included as one of the GCM diagnostics for evaluating cloud diurnal cycle in model intercomparisons.
Homogeneity of a global multisatellite soil moisture climate data record
Authors: Su Chun‐Hsu , Ryu Dongryeol , Dorigo Wouter , Zwieback Simon , Gruber Alexander , Albergel Clement , Reichle Rolf H. , Wagner Wolfgang 
Published: October 2016

AbstractClimate Data Records (CDR) that blend multiple satellite products are invaluable for climate studies, trend analysis and risk assessments. Knowledge of any inhomogeneities in the CDR is therefore critical for making correct inferences. This work proposes a methodology to identify the spatiotemporal extent of the inhomogeneities in a 36 year, global multisatellite soil moisture CDR as the result of changing observing systems. Inhomogeneities are detected at up to 24% of the tested pixels with spatial extent varying with satellite changeover times. Nevertheless, the contiguous periods without inhomogeneities at changeover times are generally longer than 10 years. Although the inhomogeneities have measurable impact on the derived trends, these trends are similar to those observed in ground data and land surface reanalysis, with an average error less than 0.003 m3 m−3 y−1. These results strengthen the basis of using the product for long‐term studies and demonstrate the necessity of homogeneity testing of multisatellite CDRs in general.
Direct space‐based observations of anthropogenic CO2 emission areas from OCO‐2
Authors: Hakkarainen J. , Ialongo I. , Tamminen J. 
Published: October 2016

AbstractAnthropogenic CO2 emissions from fossil fuel combustion have large impacts on climate. In order to monitor the increasing CO2 concentrations in the atmosphere, accurate spaceborne observations—as available from the Orbiting Carbon Observatory‐2 (OCO‐2)—are needed. This work provides the first direct observation of anthropogenic CO2 from OCO‐2 over the main pollution regions: eastern USA, central Europe, and East Asia. This is achieved by deseasonalizing and detrending OCO‐2 CO2 observations to derive CO2 anomalies. Several small isolated emission areas (such as large cities) are detectable from the anomaly maps. The spatial distribution of the CO2 anomaly matches the features observed in the maps of the Ozone Monitoring Instrument NO2 tropospheric columns, used as an indicator of atmospheric pollution. The results of a cluster analysis confirm the spatial correlation between CO2 and NO2 data over areas with different amounts of pollution. We found positive correlation between CO2 anomalies and emission inventories. The results demonstrate the power of spaceborne data for monitoring anthropogenic CO2 emissions.
Correlating laser‐generated melts with impact‐generated melts: An integrated thermodynamic‐petrologic approach
Authors: Hamann Christopher , Luther Robert , Ebert Matthias , Hecht Lutz , Deutsch Alex , Wünnemann Kai , Schäffer Sebastian , Osterholz Jens , Lexow Bernd 
Published: October 2016

AbstractPlanetary collisions in the solar system typically induce melting and vaporization of the impactor and a certain volume of the target. To study the dynamics of quasi‐instantaneous melting and subsequent quenching under postshock P‐T conditions of impact melting, we used continuous‐wave laser irradiation to melt and vaporize sandstone, iron meteorite, and basalt. Using high‐speed imaging, temperature measurements, and petrologic investigations of the irradiation targets, we show that laser‐generated melts exhibit typical characteristics of impact melts (particularly ballistic ejecta). We then calculate the entropy gains of the laser‐generated melts and compare them with the entropy gains associated with the thermodynamic states produced in hypervelocity impacts at various velocities. In conclusion, our experiments extend currently attainable postshock temperatures in impact experiments to ranges commensurate with impacts in the velocity range of 4–20 km s–1 and allow to study timescales and magnitudes of petrogenetic processes in impact melts.
The tectonic development and erosion of the Knox Subglacial Sedimentary Basin, East Antarctica
Authors: Maritati A. , Aitken A. R. A. , Young D. A. , Roberts J. L. , Blankenship D. D. , Siegert M. J. 
Published: October 2016

AbstractSedimentary basins beneath the East Antarctic Ice Sheet (EAIS) have immense potential to inform models of the tectonic evolution of East Antarctica and its ice‐sheet. However, even basic characteristics such as thickness and extent are often unknown. Using airborne geophysical data, we resolve the tectonic architecture of the Knox Subglacial Sedimentary Basin in western Wilkes Land. In addition, we apply an erosion restoration model to reconstruct the original basin geometry for which we resolve geometry typical of a transtensional pull‐apart basin. The tectonic architecture strongly indicates formation as a consequence of the rifting of India from East Gondwana from ca. 160‐130 Ma, and we suggest a spatial link with the western Mentelle Basin offshore Western Australia. The erosion restoration model shows that erosion is confined within the rift margins, suggesting that rift structure has strongly influenced the evolution of the Denman and Scott ice streams.
Saturn's quasiperiodic magnetohydrodynamic waves
Authors: Yates J. N. , Southwood D. J. , Dougherty M. K. , Sulaiman A. H. , Masters A. , Cowley S. W. H. , Kivelson M. G. , Chen C. H. K. , Provan G. , Mitchell D. G. , Hospodarsky G. B. , Achilleos N. , Sorba A. M. , Coates A. J. 
Published: October 2016

AbstractQuasiperiodic ∼1 h fluctuations have been recently reported by numerous instruments on board the Cassini spacecraft. The interpretation of the sources of these fluctuations has remained elusive to date. Here we provide an explanation for the origin of these fluctuations using magnetometer observations. We find that magnetic field fluctuations at high northern latitudes are Alfvénic, with small amplitudes (∼0.4nT), and are concentrated in wave packets similar to those observed in Kleindienst et al. (2009). The wave packets recur periodically at the northern magnetic oscillation period. We use a magnetospheric box model to provide an interpretation of the wave periods. Our model results suggest that the observed magnetic fluctuations are second harmonic Alfvén waves standing between the northern and southern ionospheres in Saturn's outer magnetosphere.
A possible precursor of the South China Sea summer monsoon onset: Effect of the South Asian High
Authors: Liu Boqi , Zhu Congwen 
Published: October 2016

AbstractIn climatology, the South China Sea (SCS) summer monsoon (SCSSM) generally onsets in Pentad 28 (16–20 May). The eastward extension of the South Asian High into the SCS in Pentad 27 is a possible precursor to the SCSSM onset. In the upper troposphere, the South Asian High (SAH) warms the air by inducing the positive potential vorticity advection, which strengthens precipitation over the southern SCS. When local convection becomes strong enough to decrease the vertical temperature gradient in Pentads 28–29, the upper level warming center overlies the subcloud warm region over the SCS to satisfy the requirement of the angular momentum conservation. A cross‐equatorial flow then forms, together with strong vertical easterly wind shear and deep monsoon convection over the SCS, marking the full establishment of the SCSSM. The abrupt change in the SAH in May could therefore be an early indicator of the onset of the SCSSM.
Alfvén wings in the lunar wake: The role of pressure gradients
Authors: Zhang H. , Khurana K. K. , Kivelson M. G. , Fatemi S. , Holmström M. , Angelopoulos V. , Jia Y. D. , Wan W. X. , Liu L. B. , Chen Y. D. , Le H. J. , Shi Q. Q. , Liu W. L. 
Published: October 2016

AbstractStrongly conducting or magnetized obstacles in a flowing plasma generate structures called Alfvén wings, which mediate momentum transfer between the obstacle and the plasma. Nonconducting obstacles such as airless planetary bodies can generate such structures, which, however, have so far been seen only in sub‐Alfvénic regime. A novel statistical analysis of simultaneous measurements made by two ARTEMIS satellites, one in the solar wind upstream of the Moon and one in the downstream wake, and comparison of the data with results of a three‐dimensional hybrid model of the interaction reveal that the perturbed plasma downstream of the Moon generates Alfvén wings in super‐Alfvénic solar wind. In the wake region, magnetic field lines bulge toward the Moon and the plasma flows are significantly perturbed. We use the simulation to show that some of the observed bends of the field result from field‐aligned currents. The perturbations in the wake thus arise from a combination of compressional and Alfvénic perturbations. Because of the super‐Alfvénic background flow of the solar wind, the two Alfvén wings fold back to form a small intersection angle. The currents that form the Alfvén wing in the wake are driven by both plasma flow deceleration and a gradient of plasma pressure, positive down the wake from the region just downstream of the Moon. Such Alfvén wing structures, caused by pressure gradients in the wake and the resulting plasma slowdown, should exist downstream of any nonconducting body in a super‐Alfvénic plasma flow.
Prediction and predictability of land and atmosphere initialized CCSM4 climate forecasts over North America
Authors: Infanti Johnna M. , Kirtman Ben P. 
Published: October 2016

AbstractSubseasonal‐to‐seasonal prediction is influenced by slowly varying surface fields such as sea surface temperature (SST) and soil moisture. Fully coupled hindcasts were recently completed in the Community Climate System Model version 4.0 (CCSM4) as part of the North American Multi‐Model Ensemble project. Using similar land and atmosphere initialization strategies, but with prescribed climatological SSTs, we attempt to determine the isolated impact of combined observed atmosphere and land initialization and of observed atmosphere initialization on monthly precipitation and 2 m temperature prediction‐estimated skill (i.e., skill assessed without SST variability) and predictability on monthly time scales. CCSM4 has been cited as having low land‐atmosphere coupling, and while combined land and atmosphere initialization significantly increases the estimated skill of precipitation and temperature in the first month after initialization (lead 0), land initialization influence is weak, consistent with low land‐atmosphere coupling in CCSM4. In contrast, atmosphere initialization is a stronger contributor to prediction skill and predictability. We find stronger influence of land and atmosphere initialization on precipitation in CCSM4 versus results from CCSM3. Predictability results show that there is potential skill to be gained for both precipitation and temperature should model errors, atmosphere or land initial state errors, and/or land‐atmosphere coupling improve.
Impacts of surface heterogeneity on dry planetary boundary layers in an urban‐rural setting
Authors: Zhu Xiaoliang , Ni Guangheng , Cong Zhentao , Sun Ting , Li Dan 
Published: October 2016

AbstractUnderstanding the impacts of land use and land‐cover change such as urbanization is essential in many disciplines. This study investigates the impacts of urban‐rural contrasts in terms of momentum roughness length (z0) and aerodynamic surface temperature (TSK) on dry planetary boundary layers (PBLs) using large‐eddy simulations (LES) with the Weather Research and Forecasting (WRF) model. In addition, the impacts of small‐scale heterogeneities within urban areas are also examined. The original WRF‐LES is modified in order to use prescribed TSK as surface boundary conditions. Numerical simulations are then conducted to examine turbulence characteristics and mesoscale circulations resulting from large‐scale urban‐rural contrasts as well as small‐scale heterogeneities in urban areas. The results indicate that (1) the urban‐rural contrasts in z0 and TSK have significant but different impacts on surface heat fluxes, mesoscale circulations, and the wind and potential temperature profiles. Compared to the case where the whole domain is homogeneous, increases in z0 and/or TSK in urban areas in the center of domain induce stronger sensible heat fluxes, stronger urban circulations, and weaker inversions at the top of the PBL. (2) When the patch size that characterizes the urban heterogeneity scale is comparable to the size of the whole urban area, the simulated results are strongly dependent on both the heterogeneity scale and the specified surface temperature values. As the patch size decreases, the simulated results become more similar to those over a homogeneous urban surface.
Oceanic single‐layer warm clouds missed by the Cloud Profiling Radar as inferred from MODIS and CALIOP measurements
Authors: Liu Dongyang , Liu Qi , Qi Lin , Fu Yunfei 
Published: October 2016

AbstractAttributed to its unique advantage of cloud vertical resolving, Cloud Profiling Radar (CPR) measurements have been used as the primary component in synthetic cloud data for relevant studies. However, due to surface clutter and sensitivity limitation, considerable warm clouds over global oceans are missed by CPR, which causes severe sampling biases and problematic statistics of cloud properties. By using independent cloud mask data jointly from Moderate Resolution Imaging Spectroradiometer and Cloud‐Aerosol Lidar with Orthogonal Polarization measurements, this study gives an evaluation on these issues and focuses on single‐layer clouds. By excluding effects from CPR's spatial resolution, the CPR detection failures are found to be frequent over global oceans, with an overall miss rate at ~0.39. For each cloud type, altocumulus, stratus, stratocumulus, and cumulus, its miss rate decreases monotonically with height, and it is only at 2.5–3.0 km altitude that the miss rate is negligible for the ensemble of oceanic single‐layer warm clouds. The miss rates are different among cloud types, which are attributed to their distinct microphysical properties. Clouds with droplet effective radius below 12 µm or cloud optical depth below 4 are very likely to be missed by CPR, resulting the globally averaged overestimation of 10–24% and 24–36%, respectively. The miss rate has a strong negative correlation with cloud water path (CWP) and decreases below 0.1 only for CWP exceeding 200 g m−2. The resulting overestimation on globally averaged CWP is 36.6 g m−2 (44.3%). Throughout the globe, the biases are mostly positive and have notable regional variations. Especially in the typical oceans that have abundant warm clouds, the CWP is overestimated by 20%–80%.
Bile acids and their oxo derivatives: Potential inhibitors of carbonic anhydrase I and II, androgen receptor antagonists and CYP3A4 substrates
Authors: Trifunović Jovana , Borčić Vladan , Mikov Momir 
Published: October 2016

AbstractSome biological properties of bile acids and their oxo derivatives have not been sufficiently investigated, although the interest in bile acids as signaling molecules is rising. The aim of this work was to evaluate physico‐chemical parametar b (slope) that represents the lipophilicity of the examined molecules and to investigate interactions of bile acids with carbonic anhydrase I, II, androgen receptor and CYP450s. Thirteen candidates were investigated using normal‐phase thin‐layer chromatography in two solvent systems. Retention parameters were used in further quantitative structure–activity relationship analysis and docking studies to predict interactions and binding affinities of examined molecules with enzymes and receptors. Prediction of activity on androgen receptor showed that compounds 3α‐hydroxy‐12‐oxo‐5β‐cholanoic and 3α‐hydroxy‐7‐oxo‐5β‐cholanoic acid have stronger antiandrogen activity than natural bile acids. The inhibitory potential for carbonic anhydrase I and II was tested and it was concluded that molecules 3α‐hydroxy‐12‐oxo‐5β‐cholanoic, 3α‐hydroxy‐7‐oxo‐5β‐cholanoic, 3,7,12‐trioxo‐5β‐cholanoic acid and hyodeoxycholic acid show the best results. Substrate behavior for CYP3A4 was confirmed for all investigated compounds. Oxo derivatives of bile acids show stronger interactions with enzymes and receptors as classical bile acids and lower membranolytic activity compared with them. These significant observations could be valuable in consideration of oxo derivatives as building blocks in medicinal chemistry.