bluuebunny/crossref_metadata_2025_split huggingface dataset:
CMIP5 earth system models with biogeochemistry: An assessment for the southwest Pacific Ocean
Authors: Rickard Graham J. , Behrens Erik , Chiswell Stephen M. 
Published: October 2016

AbstractAn assessment is made of the ability of CMIP5 models to represent the seasonal biogeochemical cycles over the late twentieth century in the southwest Pacific Ocean. In particular, sea surface temperature (SST), surface chlorophyll a, nitrate, phosphate, silicate, and the depth of the seasonal thermocline, are examined to quantify the physical‐biogeochemical capabilities of each model; the result is a “ranking” estimate enabling model ensemble generation. The better/less ranked ensembles we refer to as inner/outer, respectively. The ensembles then allow less well‐observed variables such as iron and vertically integrated primary production to be assessed. The assessment establishes model output confidence limits for setting bounds on future model scenario ecosystem change projections. By the end of the twenty first century under Representative Concentration Pathways (RCP) RCP4.5 and/or RCP8.5, our best estimates suggest that there will be average domain wide increases in SST and surface iron, but average decreases in surface chlorophyll a, nitrate, and phosphate, accompanied by relatively large decreases in the depth of the seasonal thermocline (all changes realized by both ensembles). On the other hand, for surface silicate the inner ensemble suggests general declines, and vice versa for the outer ensemble. For integrated primary production, the ensembles predict declines in subtropical water, but elsewhere generally less significant changes.
Physicochemical characteristics of black carbon aerosol and its radiative impact in a polluted urban area of China
Authors: Wang Qiyuan , Huang Ru‐Jin , Zhao Zhuzi , Cao Junji , Ni Haiyan , Tie Xuexi , Zhao Shuyu , Su Xiaoli , Han Yongming , Shen Zhenxing , Wang Yichen , Zhang Ningning , Zhou Yaqing , Corbin Joel C. 
Published: October 2016

AbstractBlack carbon (BC) aerosol plays an important role in the Earth's radiative balance. An intensive measurement campaign was conducted at Xi'an, China, from December 2012 to January 2013 to investigate the sources and physicochemical characteristics of refractory BC (rBC) and its direct radiative forcing at the surface. The overall average rBC concentration for the campaign was 8.0 ± 7.1 µg m−3. Source apportionment based on positive matrix factorization showed that traffic was the dominant rBC source (46.0%), followed by coal burning (33.9%) and biomass burning (20.1%). The rBC mass size distributions were monomodal and lognormal with larger mass median diameters for coal burning source (215 nm) compared with the traffic source (189 nm). Coal burning rBC was more strongly associated with sulfate than traffic rBC, suggesting a higher cloud condensation nuclei activity. The slope of a robust linear regression between rBC and carbon monoxide (CO) for all samples was 5.9 µg m−3 ppm−1, and the slope for the coal burning source (4.5 µg m−3 ppm−1) was larger than that for the traffic source (2.7 µg m−3 ppm−1). The net rBC emission during winter of 2009 was estimated to be 4.5 Gg based on the relationship between rBC and CO. A Tropospheric Ultraviolet and Visible radiation model showed that the average daytime value for the clear‐sky direct radiative forcing due to rBC from 23 December 2012 to 31 January 2013 was −47.7 ± 28.9 W m−2, which amounted to an average of 45.7% of the total surface atmospheric aerosol forcing.
Modulations of aerosol impacts on cloud microphysics induced by the warm Kuroshio Current under the East Asian winter monsoon
Authors: Koike M. , Asano N. , Nakamura H. , Sakai S. , Nagao T. M. , Nakajima T. Y. 
Published: October 2016

AbstractIn our previous aircraft observations, the possible influence of high sea surface temperature (SST) along the Kuroshio Current on aerosol‐cloud interactions over the western North Pacific was revealed. The cloud droplet number concentration (Nc) was found to increase with decreasing near‐surface static stability (NSS), which was evaluated locally as the difference between the SST and surface air temperature (SAT). To explore the spatial and temporal extent to which this warm SST influence can be operative, the present study analyzed Nc values estimated from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite measurements. The comparison of the local Nc values between the high and low SST − SAT days revealed a marked increase in Nc (up to a factor of 1.8) along the Kuroshio Current in the southern East China Sea, where particularly high SST − SAT values (up to 8 K) were observed in winter under monsoonal cold air outflows from the Asian Continent. This cold airflow destabilizes the atmospheric boundary layer, which leads to enhanced updraft velocities within the well‐developed mixed layer and thus greater Nc. The monsoonal northwesterlies also bring a large amount of anthropogenic aerosols from the Asian continent that increase Nc in the first place. These results suggest that the same modulations of cloud microphysics can occur over other warm western boundary currents, including the Gulf Stream, under polluted cool continental airflows. Possibilities of influencing the cloud liquid water path are also discussed.
Isotopic ordering in atmospheric O2 as a tracer of ozone photochemistry and the tropical atmosphere
Authors: Yeung Laurence Y. , Murray Lee T. , Ash Jeanine L. , Young Edward D. , Boering Kristie A. , Atlas Elliot L. , Schauffler Sue M. , Lueb Richard A. , Langenfelds Ray L. , Krummel Paul. B. , Steele L. Paul , Eastham Sebastian D. 
Published: October 2016

AbstractThe distribution of isotopes within O2 molecules can be rapidly altered when they react with atomic oxygen. This mechanism is globally important: while other contributions to the global budget of O2 impart isotopic signatures, the O(3P) + O2 reaction resets all such signatures in the atmosphere on subdecadal timescales. Consequently, the isotopic distribution within O2 is determined by O3 photochemistry and the circulation patterns that control where that photochemistry occurs. The variability of isotopic ordering in O2 has not been established, however. We present new measurements of 18O18O in air (reported as Δ36 values) from the surface to 33 km altitude. They confirm the basic features of the clumped‐isotope budget of O2: Stratospheric air has higher Δ36 values than tropospheric air (i.e., more 18O18O), reflecting colder temperatures and fast photochemical cycling of O3. Lower Δ36 values in the troposphere arise from photochemistry at warmer temperatures balanced by the influx of high‐Δ36 air from the stratosphere. These observations agree with predictions derived from the GEOS‐Chem chemical transport model, which provides additional insight. We find a link between tropical circulation patterns and regions where Δ36 values are reset in the troposphere. The dynamics of these regions influences lapse rates, vertical and horizontal patterns of O2 reordering, and thus the isotopic distribution toward which O2 is driven in the troposphere. Temporal variations in Δ36 values at the surface should therefore reflect changes in tropospheric temperatures, photochemistry, and circulation. Our results suggest that the tropospheric O3 burden has remained within a ±10% range since 1978.
Contribution of soil moisture variability to summer precipitation in the Northern Hemisphere
Authors: Yang Kai , Wang Chenghai , Bao Hongyan 
Published: October 2016

AbstractThe variability and impacts of spring soil moisture (SSM) over the Northern Hemisphere (NH) in the recent 30 years are investigated. The results show that there are two maximum regions of interannual variability of SSM, which are located in the central region of North America (Region 1), and Europe and West Asia (Region 2). These two regions are crucial areas of land‐atmosphere interaction; SSM in these two regions is closely connected with subsequent summer precipitation in NH. Four simulation experiments show that compared to the oceanic effect, the SSM has a positive contribution to summer precipitation over northern Europe, central Asia, and the southern region of North America but a negative contribution to the central region of North America, Arabia, and India, which accounts for 5%–10% of the summer precipitation based on the regional average. The SSM has significant impacts on subsequent summer precipitation in the midlatitudes, while the oceanic impact is dominant over tropical continents. The regions with remarkable variability of SSM are the areas where the coupling between SSM and summer precipitation is relatively strong. The anomalous SSM over NH primarily influences the general circulation through diabatic heating anomalies and changes the low‐level moisture condition, leading to the anomalies of summer precipitation.
A decision tree algorithm for investigation of model biases related to dynamical cores and physical parameterizations
Authors: Soner Yorgun M. , Rood Richard B. 
Published: October 2016

AbstractAn object‐based evaluation method using a pattern recognition algorithm (i.e., classification trees) is applied to the simulated orographic precipitation for idealized experimental setups using the National Center of Atmospheric Research (NCAR) Community Atmosphere Model (CAM) with the finite volume (FV) and the Eulerian spectral transform dynamical cores with varying resolutions. Daily simulations were analyzed and three different types of precipitation features were identified by the classification tree algorithm. The statistical characteristics of these features (i.e., maximum value, mean value, and variance) were calculated to quantify the difference between the dynamical cores and changing resolutions. Even with the simple and smooth topography in the idealized setups, complexity in the precipitation fields simulated by the models develops quickly. The classification tree algorithm using objective thresholding successfully detected different types of precipitation features even as the complexity of the precipitation field increased. The results show that the complexity and the bias introduced in small‐scale phenomena due to the spectral transform method of CAM Eulerian spectral dynamical core is prominent, and is an important reason for its dissimilarity from the FV dynamical core. The resolvable scales, both in horizontal and vertical dimensions, have significant effect on the simulation of precipitation. The results of this study also suggest that an efficient and informative study about the biases produced by GCMs should involve daily (or even hourly) output (rather than monthly mean) analysis over local scales.
Chemo‐Catalyzed Pathways to Lactic Acid and Lactates
Authors: Shuklov I. A. , Dubrovina N. V. , Kühlein K. , Börner A. 
Published: October 2016

AbstractLactic acid is an important building block for the production of biodegradable polymers (PLLA, PDLA, etc.) as well as starting material for the pharmaceutical industry. The current production of this chiral compound is dominated by fermentation processes. However many catalytic reactions that could be used for manufacturing lactic acid were developed in the past three decades. High reaction rates and simple separation of products in comparison to fermentation characterize many of these processes. Excellent stereoselectivities up to 99% ee could be achieved. This review aims to give a critical overview of chemical processes applying catalysis as an alternative for the production of both enantiomerically pure and racemic lactic acid and lactates. The efficiency and economy of these processes are analyzed.magnified image
Why Does Disaster Recovery Work Influence Mental Health?: Pathways through Physical Health and Household Income
Authors: Lowe Sarah R. , Kwok Richard K. , Payne Julianne , Engel Lawrence S. , Galea Sandro , Sandler Dale P. 
Published: October 2016

AbstractDisaster recovery work increases risk for mental health problems, yet the mechanisms underlying this association are unclear. We explored links from recovery work to post‐traumatic stress (PTS), major depression (MD), and generalized anxiety disorder (GAD) symptoms through physical health symptoms and household income in the aftermath of the Deepwater Horizon oil spill. As part of the NIEHS GuLF STUDY, participants (N = 10,141) reported on cleanup work activities, spill‐related physical health symptoms, and household income at baseline, and mental health symptoms an average of 14.69 weeks (SD = 16.79) thereafter. Cleanup work participation was associated with higher physical health symptoms, which in turn were associated with higher PTS, MD, and GAD symptoms. Similar pattern of results were found in models including workers only and investigating the influence of longer work duration and higher work‐related oil exposure on mental health symptoms. In addition, longer worker duration and higher work‐related oil exposure were associated with higher household income, which in turn was associated with lower MD and GAD symptoms. These findings suggest that physical health symptoms contribute to workers’ risk for mental health symptoms, while higher household income, potentially from more extensive work, might mitigate risk.
Psychological Empowerment Among Urban Youth: Measurement Model and Associations with Youth Outcomes
Authors: Eisman Andria B. , Zimmerman Marc A. , Kruger Daniel , Reischl Thomas M. , Miller Alison L. , Franzen Susan P. , Morrel‐Samuels Susan 
Published: October 2016

AbstractEmpowerment‐based strategies have become widely used method to address health inequities and promote social change. Few researchers, however, have tested theoretical models of empowerment, including multidimensional, higher‐order models. We test empirically a multidimensional, higher‐order model of psychological empowerment (PE), guided by Zimmerman's conceptual framework including three components of PE: intrapersonal, interactional, and behavioral. We also investigate if PE is associated with positive and negative outcomes among youth. The sample included 367 middle school youth aged 11–16 (M = 12.71; SD = 0.91); 60% female, 32% (n = 117) white youth, 46% (n = 170) African‐American youth, and 22% (n = 80) identifying as mixed race, Asian‐American, Latino, Native American, or other ethnic/racial group; schools reported 61–75% free/reduced lunch students. Our results indicated that each of the latent factors for the three PE components demonstrate a good fit with the data. Our results also indicated that these components loaded on to a higher‐order PE factor (X2 = 32.68; df: 22; p = .07; RMSEA: 0.04; 95% CI: .00, .06; CFI: 0.99). We found that the second‐order PE factor was negatively associated with aggressive behavior and positively associated with prosocial engagement. Our results suggest that empowerment‐focused programs would benefit from incorporating components addressing how youth think about themselves in relation to their social contexts (intrapersonal), understanding social and material resources needed to achieve specific goals (interactional), and actions taken to influence outcomes (behavioral). Our results also suggest that integrating the three components and promoting PE may help increase likelihood of positive behaviors (e.g., prosocial involvement); we did not find an association between PE and aggressive behavior. Implications and future directions for empowerment research are discussed.
A review of mortality associated with elongate mineral particle (EMP) exposure in occupational epidemiology studies of gold, talc, and taconite mining
Authors: Mandel Jeffrey H. , Alexander Bruce H. , Ramachandran Gurumurthy 
Published: October 2016

BackgroundMining of gold, taconite, and talc may involve exposure to elongate mineral particles (EMP). The involved EMPs are typically non‐asbestiform, include dimensions that regulatory definitions exclude, and have been less studied.MethodsA review of the literature was undertaken for this exposure and occupational epidemiological studies that occur in gold, talc, and taconite mining.ResultsQuantitative EMP exposure information in these industries is incomplete. However, there are consistent findings of pneumoconiosis in each of these types of mining. A recent case‐control study suggests a possible association between this exposure and mesothelioma. Lung cancer is inconsistently reported in these industries and is an unlikely outcome of non‐asbestiform EMP exposure. There is evidence of cardiovascular mortality excess across all of these types of mining.ConclusionsNon‐malignant respiratory disease and cardiovascular mortality have been consistently increased in these industries. Further investigation, including additional insights for the role of non‐asbestiform EMP, is warranted. Am. J. Ind. Med. 59:1047–1060, 2016. © 2016 Wiley Periodicals, Inc.
Do leprosy and tuberculosis generate a systemic inflammatory shift? Setting the ground for a new dialogue between experimental immunology and bioarchaeology
Authors: Crespo Fabian A. , Klaes Christopher K. , Switala Andrew E. , DeWitte Sharon N. 
Published: October 2016

AbstractIt is possible that during long lasting chronic infections such as tuberculosis (TB) and leprosy individuals who generate a stronger immune response will produce a chronic shift in the systemic levels of inflammatory proteins. Consequently, the systemic immunological shift could affect inflammatory responses against other persistent pathogens such as Porphyromonas gingivalis associated with periodontal disease (PD).ObjectiveTo determine if in vitro exposure to Mycobacterium tuberculosis or M. leprae lysates impacts subsequent immune responses to P. gingivalis; and to propose a new dialogue between experimental immunology and paleopathology.Material and methodsWe sequentially (2 days protocol) exposed peripheral blood mononuclear cells (PBMCs) from healthy donors to bacterial lysates either from M. tuberculosis, or M. leprae, or P. gingivalis. After collecting all supernatants, we measured the expression of immune proteins TNFα and IFNγ using an enzyme‐linked immunosorbent assay.ResultsEarly exposure (day 1) of PBMCs to M. leprae or M. tuberculosis lysates induces an inflammatory shift detected by the increase of TNFα and IFNγ when the same cells are subsequently (day 2) exposed to oral pathogen P. gingivalis.DiscussionBy extrapolating these results, we suggest that chronic infections, such as TB and leprosy, could generate a systemic immunological shift that can affect other inflammatory processes such the one present in PD. We propose that the presence and severity of PD should be explored as a proxy for inflammatory status or competence when reconstructing the health profile in past populations.
3D Structure Determination of an Unstable Transient Enzyme Intermediate by Paramagnetic NMR Spectroscopy
Authors: Chen Jia‐Liang , Wang Xiao , Yang Feng , Cao Chan , Otting Gottfried , Su Xun‐Cheng 
Published: October 2016

AbstractEnzyme catalysis relies on conformational plasticity, but structural information on transient intermediates is difficult to obtain. We show that the three‐dimensional (3D) structure of an unstable, low‐abundance enzymatic intermediate can be determined by nuclear magnetic resonance (NMR) spectroscopy. The approach is demonstrated for Staphylococcus aureus sortase A (SrtA), which is an established drug target and biotechnological reagent. SrtA is a transpeptidase that converts an amide bond of a substrate peptide into a thioester. By measuring pseudocontact shifts (PCSs) generated by a site‐specific cysteine‐reactive paramagnetic tag that does not react with the active‐site residue Cys184, a sufficient number of restraints were collected to determine the 3D structure of the unstable thioester intermediate of SrtA that is present only as a minor species under non‐equilibrium conditions. The 3D structure reveals structural changes that protect the thioester intermediate against hydrolysis.
Effect of weak base modification on ZSM‐5 catalyst for methanol to aromatics
Authors: Feng Wei , Gao Xiaofeng , Ding Chuanmin , Jia Yanming , Wang Junwen , Zhang Kan , Liu Ping 
Published: October 2016

The effect of weak base modification on the catalytic performance of ZSM‐5 catalyst for conversion of methanol to aromatics was investigated. The catalysts were characterized using X‐ray diffraction, X‐ray fluorescence, N2 adsorption–desorption, NH3 temperature‐programmed desorption, Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetry. The results showed that catalysts treated with weak base (NaHCO3, Na2CO3 and NH3⋅H2O) exhibited a pore structure with interconnected micropores and mesopores. The existence of mesopores was beneficial for improving the diffusion of reactants and products, and the coke deposition resistance capacity of treated catalysts was enhanced greatly. Meanwhile, compared to traditional ZSM‐5 zeolite, the ratio of Brønsted to Lewis (B/L) acid sites of ZSM‐5/NH3⋅H2O (B/L = 7.35) zeolite slightly increased but the amount of acid sites reduced, while those of ZSM‐5/NaHCO3 (B/L = 0.127) and ZSM‐5/Na2CO3 (B/L = 0.107) significantly reduced. Further, the catalyst treated with NH3⋅H2O solution was evaluated in the methanol to aromatics reaction and led to an enhanced aromatization reaction rate. The liquid hydrocarbons product distribution exhibited higher aromatic hydrocarbons yield (56.12%) and selectivity (40.28%) of benzene, toluene and xylene (BTX) with isoparaffin content reducing to 26.17%, which could be explained by appropriate B/L acid sites ratio, higher pore volumes and higher surface area.
Photodegradation of methyl orange dye by ZnO loaded onto carbon xerogels composites
Authors: Farag Hala K. , Aboelenin Reham M. M. , Fathy Nady A. 
Published: October 2016

AbstractThe present paper studies the photocatalytic behavior of pure zinc oxide (ZnO) and ZnO loaded onto carbon xerogel as a substrate. These samples were prepared by a sol‐gel process in presence of either an ionic liquid or an alcohol such as 1‐ethyl‐3‐methylimidazolium trifluoromethylsulfonate (A) or isopropanol solvent (B) to produce ZnO‐CX‐A and ZnO‐CX‐B photocatalysts, respectively. Transmission electron microscopy and X‐ray diffraction proved that ZnO particles were prepared as nanoflakes‐like with amorphous phase. Fourier transform infrared spectroscopy showed that ZnO‐CX‐A has a variety of surface functional groups that accelerated the photocatalytic activity of composite. The photocatalytic activity of the prepared photocatalysts was evaluated using methyl orange (MO) azo dye as a model organic compound under visible light source. As a result of the photodegradation experiments, the MO dye was completely degraded by the prepared ZnO‐CX photocatalyst composites in 120 min rather than that performed using ZnO and CX photocatalysts. However, a 98% of the MO dye solution was degraded within 90 min over ZnO‐CX‐A. The separation and reusability runs of ZnO‐CX‐A photocatalyst showed that the catalyst has high photodegradation efficiencies reaching up to 90% in the fourth run and afterward decreased to 60% in the fifth reuse. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.