bluuebunny/crossref_metadata_2025 huggingface dataset:
454 pyrosequencing-based characterization of the bacterial consortia in a well established nitrifying reactor
Authors: Ramirez-Vargas Rocio , Serrano-Silva Nancy , Navarro-Noya Yendi E. , Alcántara-Hernández Rocio J. , Luna-Guido Marco , Thalasso Frederic , Dendooven Luc
Published: September 2015

This present study aimed to characterize the bacterial community in a well-established nitrifying reactor by high-throughput sequencing of 16S rRNA amplicons. The laboratory-scale continuous stirred tank reactor has been supplied with ammonium (NH4+) as sole energy source for over 5 years, while no organic carbon has been added, assembling thus a unique planktonic community with a mean NH4+ removal rate of 86 ± 1.4 mg NH4+-N/(L d). Results showed a nitrifying community composed of bacteria belonging to Nitrosomonas (relative abundance 11.0%) as the sole ammonia oxidizers (AOB) and Nitrobacter (9.3%) as the sole nitrite oxidizers (NOB). The Alphaproteobacteria (42.3% including Nitrobacter) were the most abundant class within the Proteobacteria (62.8%) followed by the Gammaproteobacteria (9.4%). However, the Betaproteobacteria (excluding AOB) contributed only 0.08%, confirming that Alpha- and Gammaproteobacteria thrived in low-organic-load environments while heterotrophic Betaproteobacteria are not well adapted to these conditions. Bacteroidetes, known to metabolize extracellular polymeric substances produced by nitrifying bacteria and secondary metabolites of the decayed biomass, was the second most abundant phylum (30.8%). It was found that Nitrosomonas and Nitrobacter sustained a broad population of heterotrophs in the reactor dominated by Alpha- and Gammaproteobacteria and Bacteroidetes, in a 1:4 ratio of total nitrifiers to all heterotrophs.
Removal of Pb(II) by adsorption onto Chinese walnut shell activated carbon
Authors: Yi Zheng-ji , Yao Jun , Kuang Yun-fei , Chen Hui-lun , Wang Fei , Yuan Zhi-min
Published: September 2015

The excessive discharge of Pb(II) into the environment has increasingly aroused great concern. Adsorption is considered as the most effective method for heavy metal removal. Chinese walnut shell activated carbon (CWSAC) was used as an adsorbent for the removal of Pb(II) from aqueous solution. Batch experiments were conducted by varying contact time, temperature, pH, adsorbent dose and initial Pb(II) concentration. Adsorption equilibrium was established within 150 min. Although temperature effect was insignificant, the Pb(II) adsorption was strongly pH dependent and the maximum removal was observed at pH 5.5. The Pb(II) removal efficiency increased with increasing CWSAC dosage up to 2.0 g/L and reached a maximum of 94.12%. Langmuir and Freundlich adsorption isotherms were employed to fit the adsorption data. The results suggested that the equilibrium data could be well described by the Langmuir isotherm model, with a maximum adsorption capacity of 81.96 mg/g. Adsorption kinetics data were fitted by pseudo-first- and pseudo-second-order models. The result indicated that the pseudo-first-order model best describes the adsorption kinetic data. In summary, CWSAC could be a promising material for the removal of Pb(II) from wastewater.
The Influence of Climate Change on Atmospheric Deposition of Mercury in the Arctic—A Model Sensitivity Study
Authors: Hansen Kaj , Christensen Jesper , Brandt Jørgen
Published: September 2015

Mercury (Hg) is a global pollutant with adverse health effects on humans and wildlife. It is of special concern in the Arctic due to accumulation in the food web and exposure of the Arctic population through a rich marine diet. Climate change may alter the exposure of the Arctic population to Hg. We have investigated the effect of climate change on the atmospheric Hg transport to and deposition within the Arctic by making a sensitivity study of how the atmospheric chemistry-transport model Danish Eulerian Hemispheric Model (DEHM) reacts to climate change forcing. The total deposition of Hg to the Arctic is 18% lower in the 2090s compared to the 1990s under the applied Special Report on Emissions Scenarios (SRES-A1B) climate scenario. Asia is the major anthropogenic source area (25% of the deposition to the Arctic) followed by Europe (6%) and North America (5%), with the rest arising from the background concentration, and this is independent of the climate. DEHM predicts between a 6% increase (Status Quo scenario) and a 37% decrease (zero anthropogenic emissions scenario) in Hg deposition to the Arctic depending on the applied emission scenario, while the combined effect of future climate and emission changes results in up to 47% lower Hg deposition.
Spark Plasma Sintering of Commercial Zirconium Carbide Powders: Densification Behavior and Mechanical Properties
Authors: Wei Xialu , Back Christina , Izhvanov Oleg , Khasanov Oleg , Haines Christopher , Olevsky Eugene
Published: September 2015

Commercial zirconium carbide (ZrC) powder is consolidated by Spark Plasma Sintering (SPS). Processing temperatures range from 1650 to 2100 °C. Specimens with various density levels are obtained when performing single-die SPS at different temperatures. Besides the single-die tooling setup, a double-die tooling setup is employed to largely increase the actual applied pressure to achieve higher densification in a shorter processing time. In order to describe the densification mechanism of ZrC powder under SPS conditions, a power-law creep constitutive equation is utilized, whose coefficients are determined by the inverse regression of the obtained experimental data. The densification of the selected ZrC powder is shown to be likely associated with grain boundary sliding and dislocation glide controlled creep. Transverse rupture strength and microhardness of sintered specimens are measured to be up to 380 MPa and 24 GPa, respectively. Mechanical properties are correlated with specimens’ average grain size and relative density to elucidate the co-factor dependencies.
Using Multiple Tools to Analyze Resource Exchange in China
Authors: Li Nan , Zhang Tianzhu , Qi Jianchuan , Huang Yuanyi
Published: September 2015

With the rapid development of globalization, the function of international physical resource exchange is becoming increasingly important in economic growth through resource optimization. However, most existing ecological economy studies use physical trade balance (PTB) directly or use physical imports and exports individually to analyze national material metabolization. Neither the individual analysis of physical imports and exports nor the direct analysis of PTB is capable of portraying the comprehensive contributions of a certain product to total physical trade. This study introduced an indicator, i.e., the physical contribution to the trade balance (PCB), which evolved from the traditional index of contribution to the trade balance (CB). In addition, trade balance (TB), PTB, CB, and PCB were systematically related and combined. An analysis was conducted using the four tools to obtain overall trade trends in China. This study discovered that both physical trade value and quantity exhibited different characteristics when China joined the World Trade Organization in 2002 and experienced the global economic crisis in 2009. Finally, the advantages of a supporting policy decision by applying multiple analytical tools to physical trade were discussed.
Robust bifunctional aluminium–salen catalysts for the preparation of cyclic carbonates from carbon dioxide and epoxides
Authors: Rulev Yuri A , Gugkaeva Zalina , Maleev Victor I , North Michael , Belokon Yuri N
Published: September 2015

Two new one-component aluminium-based catalysts for the reaction between epoxides and carbon dioxide have been prepared. The catalysts are composed of aluminium–salen chloride complexes with trialkylammonium groups directly attached to the aromatic rings of the salen ligand. With terminal epoxides, the catalysts induced the formation of cyclic carbonates under mild reaction conditions (25–35 °C; 1–10 bar carbon dioxide pressure). However, with cyclohexene oxide under the same reaction conditions, the same catalysts induced the formation of polycarbonate. The catalysts could be recovered from the reaction mixture and reused.
Les formes différenciées d’usages de produits psychoactifs au travail : les cas des bars-restaurants et des chantiers du bâtiment
Authors: Ngo Nguene Marie Rosaire
Published: September 2015

Cet article rend compte des formes différenciées d’usages d’alcool, de cocaïne et de cannabis des salariés des bars-restaurants et chantiers du bâtiment en s’appuyant sur des matériaux d’enquêtes essentiellement qualitatifs, recueillis dans le cadre d’un travail de thèse en cours 1 . Les consommations de produits psychoactifs dans ces organisations suivent des logiques collectives et individuelles qu’il convient d’expliquer. Pour cela, nos analyses prendront conjointement en compte les conditions de travail proprement dites (travail de nuit dans le secteur bar-restauration, pénibilité physique dans les chantiers du bâtiment, par exemple) ; les dynamiques sociales et culturelles des usages de substances psychoactives, leurs propriétés physiques et chimiques ; les caractéristiques sociales des salariés, examinés à travers leurs trajectoires personnelles et professionnelles, en prenant en compte les effets d’âge et de génération.
Mythe et histoire dans l’exegèse médiévalede la genèse
Authors: Dahan Gilbert
Published: September 2015

Les exégètes médiévaux ont-ils une attitude particulière à l’égard des récits de la Bible que nous faisons aujourd’hui entrer dans la catégorie du « mythe » ? On voudrait répondre à cette question à partir de l’étude des généalogies des chapitres 4 et 5 de la Genèse dans les commentaires composés entre le xii e et le xiv e siècles en Occident. Celles du chapitre 4 (v. 17-22) sont considérées comme un mythe sur les origines de la culture – la vie pastorale, le travail des métaux, la musique, le tissage –, celles du chapitre 5 posent des problèmes divers, notamment du fait de la longueur de la vie des personnages nommés. Il semble que les commentateurs du Moyen Âge soient moins sensibles à la dimension « historique » de ces textes qu’aux enseignements que nous pouvons en tirer sur les fondements de la conduite humaine. L’analyse qu’ils font des structures de ces textes (utilisant notamment la valeur symbolique attachée aux nombres et mettant en relief les différences d’agencement) et les applications tropologiques qu’ils en tirent, puisznt dans l’Écriture sainte les enseignements d’une Parole adressée en permanence à l’homme, permettent de constater que les procédures qu’ils mettent en œuvre sont proches de celles d’une certaine analyse des mythes aujourd’hui.
Análisis comparativo del consumo energético de un sistema de calentamiento por inducción a alta frecuencia para aplicaciones de procesado de materiales
Authors: Taştan Mehmet , Gökozan Hayrettin , Taşkin Sezai , Çavdar Uğur
Published: September 2015

En este estudio se comparan los consumos energéticos al procesar Ti-6Al-4V por inducción a 900 kHz. Se ha analizado la potencia total consumida y la energía consumida por muestra. Los experimentos se han realizado en un sistema de inducción de ultra alta frecuencia a 900 kHz, 2,8 kW. Se han considerado dos casos, en el primero se ha calentado Ti-6Al-4V a 900 °C por el método clásico usado en la industria y enfriado en agua; posteriormente las muestras se han calentado a 600, 650 y 700 °C y enfriadas al aire para relajar tensiones. En los tres casos se midió el consumo energético. En el segundo caso, cinco muestras diferentes fueron tratadas a temperaturas entre 660 y 1120 °C, midiendo el consumo energético en todos los casos. Asimismo se analizó el efecto del incremento de temperatura en el consumo energético, observándose que al calentar los materiales de base titanio usados en este trabajo con inducción de alta frecuencia, el consumo energético aumenta al aumentar la temperatura, siendo la velocidad de incremento del consumo energético mayor que la velocidad de incremento de la temperatura.
Micromechanical Properties of Biocompatible Materials for Bone Tissue Engineering Produced by Direct 3D Printing
Authors: Koudelka Petr , Doktor Tomáš , Kytyr Daniel , Fenclova Nela , Sepitka Josef , Lukes Jaroslav
Published: September 2015

Bone implants in form of artificial scaffolds manufactured from poly-lactic acid (PLA) represent an attractive alternative to traditional surgical treatments of defective bones (i.e. autografts and allografts). In this work factors influencing biocompatibility and primary stability of implants manufactured from PLA using direct 3D printing were assessed using nanoindentation. For this reason bulk sample of the PLA material and a printed object were subjected to nanomechanical measurement. Quasi-static nanoindentation was employed to identify elastic modulus and hardness distribution on surface and within volume of the samples. Moreover mechanical properties along scanning direction and interlayer characteristics were also assessed. Gradients in mechanical properties have been identified within volume of the material, within the printing layers and at contact between individual layers.
Local Mechanical Properties of Cu-Co Alloys with Coherent Co Precipitates
Authors: Buršík Jiří , Buršíková Vilma , Svoboda Milan
Published: September 2015

In this work the influence of the thermal treatment on the local mechanical properties of model diluted Cu-Co alloys with Co content of 4 at.% is investigated. The samples underwent annealing at 1273 K followed by water quenching. The further thermal treatment at 1073 K of the oversaturated solid solution generated a fine distribution of Co-rich precipitates. Parameters of microstructure were evaluated by means of analytical electron microscopy. The nanoscale mechanical properties of precipitates, areas adjacent to the precipitates and precipitate-free zones were studied using large area grid indentation tests. Moreover, the modulus mapping capability was applied to obtain quantitative maps of the storage and loss stiffness and modulus.
Barrage Lock Concrete Porosity Evaluation Using X-Ray Microtomography
Authors: Bywalski Czesław , Rajczakowska Magdalena , Sadowski Łukasz
Published: September 2015

This paper deals with the use of X-ray microtomography in evaluating the porosity of barrage lock concrete. The main parts of the lock were built in the years 1914-1917. Its high and low heads were founded on 2.70 m thick concrete slabs. Samples for laboratory tests were taken by core drilling at half of the slab thickness. The compressive strength of the concrete was determined and the porosity of the concrete was evaluated using X-ray microtomography. The compressive strength values ranged from 17.3 to 37.3 MPa. The porosity examination results are compared with the destructively determined concrete compressive strength values.
Liver histopathological changes in Clarias gariepinus exposed to ethanol extract of Adenium obesum stem bark
Authors: Abalaka S. , Fatihu M. , Ibrahim N. , Ambali S.
Published: September 2015

Introduction: Histopathological effects of ethanol extract of Adenium obesum stem bark on the liver of Clariasgariepinus was investigated over a 96-h exposure period as an effective organic piscicide. Materials and Methods: An acute static toxicity bioassay was performed after a preliminary concentration range finding test was conducted. Results: Exposed fish showed adaptation behavioural changes with those of respiratory distress and abnormal nervous signs of toxicity, which was concentration-dependent. Mortality was recorded in some of the exposed fish while a median lethal concentration of 7.15 mgL-1 was established for the extract in the exposed fish. Non-significant (p>0.05) changes were recorded in serum aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase activities of the exposed ish. Moderate liver damage was observed in the exposed fish based on the degree of tissue change (DTC) grading where significant (p<0.05) differences were observed between the DTC of the exposed groups and the control. Conclusion: Ethanol extract of A. obesum stem bark was toxic to the exposed fish with evidence of hepatotoxicity and therefore, can be used to eradicate the hardy C.gariepinus from aquatic environments.
Fog composition at Baengnyeong Island in the Eastern Yellow Sea: detecting markers of aqueous atmospheric oxidations
Authors: Boris A. J. , Lee T. , Park T. , Choi J. , Seo S. , Collett J. L.
Published: September 2015

Abstract. Samples of fog water were collected at Baengnyeong Island (BYI) in the Yellow Sea during the summer of 2014. The most abundant chemical species in the fog water were NH4+ (mean of 2220 μM), NO3− (1260 μM), SO4−2 (730 μM), and Na+ (551 μM), with substantial contributions from other ions consistent with marine and biomass burning influence on some dates. The pH of the samples ranged between 3.48 and 5.00, with a mean of 3.94, intermediate within pH values of fog/cloud water reported previously in Southeast Asia. Back trajectories (72 h) showed that high relative humidity (> 80 %) was encountered upwind of the sampling site by all but one of the sampled air masses, and that the fog composition at BYI can be impacted by several different source regions, including the Sea of Japan, Northeastern China, and the East China Sea. Sulfur in the collected fog was highly oxidized: low S(IV) concentrations were measured (mean of 2.36 μM) in contrast to SO4−2 and in contrast to fog/cloud S(IV) concentrations from pollutant source regions; organosulfate species were also observed and were most likely formed through aging of mainly biogenic volatile organic compounds. Low molecular mass organic acids were major contributors to total organic carbon (TOC; 36–69 %), comprising a fraction of TOC at the upper end of that seen in fogs and clouds in other polluted environments. Large contributions were observed from not only acetic and formic acids, but also oxalic, succinic, maleic, and other organic acids that can be produced in aqueous atmospheric organic processing (AAOP) reactions. These samples of East Asian fog water containing highly oxidized components represent fog downwind of pollutant sources and can provide new insight into the fate of regional emissions. In particular, these samples demonstrate the result of extensive photochemical aging during multiday transport, including oxidation within wet aerosols and fogs.
Simulation of the Indian summer monsoon onset-phase rainfall using a regional model
Authors: Srinivas C. V. , Hari Prasad D. , Bhaskar Rao D. V. , Baskaran R. , Venkatraman B.
Published: September 2015

Abstract. This study examines the ability of the Advanced Research WRF (ARW) regional model to simulate Indian summer monsoon (ISM) rainfall climatology in different climate zones during the monsoon onset phase in the decade 2000–2009. The initial and boundary conditions for ARW are provided from the NCEP/NCAR Reanalysis Project (NNRP) global reanalysis. Seasonal onset-phase rainfall is compared with corresponding values from 0.25° IMD (India Meteorological Department) rainfall and NNRP precipitation data over seven climate zones (perhumid, humid, dry/moist, subhumid, dry/moist, semiarid and arid) of India to see whether dynamical downscaling using a regional model yields advantages over just using large-scale model predictions. Results show that the model could simulate the onset phase in terms of progression and distribution of rainfall in most zones (except over the northeast) with good correlations and low error metrics. The observed mean onset dates and their variability over different zones are well reproduced by the regional model over most climate zones. It has been found that the ARW performed similarly to the reanalysis in most zones and improves the onset time by 1 to 3 days in zones 4 and 7, in which the NNRP shows a delayed onset compared to the actual IMD onset times. The variations in the onset-phase rainfall during the below-normal onset (June negative) and above-normal onset (June positive) phases are well simulated. The slight underestimation of onset-phase rainfall in the northeast zone could be due to failure in resolving the wide extent of topographic variations and the associated multiscale interactions in that zone. Spatial comparisons showed improvement of pentad rainfall in both space and quantity in ARW simulations over NNRP data, as evident from a wider eastward distribution of pentad rainfall over the Western Ghats, central and eastern India, as in IMD observations. While NNRP under-represented the high pentad rainfall over northeast, east and west coast areas, the ARW captured these regional features showing improvement upon NNRP reanalysis, which may be due to the high resolution (30 km) employed. The onset-phase rainfall characteristics during the contrasting ISM of 2003 and 2009 are well simulated in terms of the variations in the strength of low-level jet (LLJ) and outgoing long-wave radiation (OLR).
Stable isotope and calcareous nannofossil assemblage records for the Cicogna section: toward a detailed template of late Paleocene and early Eocene global carbon cycle and nannoplankton evolution
Authors: Agnini C. , Spofforth D. J. A. , Dickens G. R. , Rio D. , Pälike H. , Backman J. , Muttoni G. , Dallanave E.
Published: September 2015

Abstract. We present records of stable carbon and oxygen isotopes, CaCO3 content, and changes in calcareous nannofossil assemblages across an 81 m thick section of upper Paleocene-lower Eocene marine sedimentary rocks now exposed along Cicogna Stream in northeast Italy. The studied stratigraphic section represents sediment accumulation in a bathyal hemipelagic setting from approximately 57.5 to 52.2 Ma, a multi-million-year time interval characterized by perturbations in the global carbon cycle and changes in calcareous nannofossil assemblages. The bulk carbonate δ13C profile for the Cicogna section, once placed on a common time scale, resembles that at several other locations across the world, and includes both a long-term drop in δ13C, and multiple short-term carbon isotope excursions (CIEs). This precise correlation of widely separated δ13C records in marine sequences results from temporal changes in the carbon composition of the exogenic carbon cycle. However, diagenesis has likely modified the δ13C record at Cicogna, an interpretation supported by variations in bulk carbonate δ18O, which do not conform to expectations for a primary signal. The record of CaCO3 content reflects a combination of carbonate dilution and dissolution, as also inferred at other sites. Our detailed documentation and statistical analysis of calcareous nannofossil assemblages show major differences before, during and after the Paleocene Eocene Thermal Maximum. Other CIEs in our lower Paleogene section do not exhibit such a distinctive change; instead, these events are sometimes characterized by variations restricted to a limited number of taxa and transient shifts in the relative abundance of primary assemblage components. Both long-lasting and short-lived modifications to calcareous nannofossil assemblages preferentially affected nannoliths or holococcoliths such as Discoaster, Fasciculithus, Rhomboaster/Tribrachiatus, Spenolithus and Zygrhablithus, which underwent distinct variations in abundance as well as permanent evolutionary changes in terms of appearances and disappearances. By contrast, placoliths such as Coccolithus and Toweius, which represent the main component of the assemblages, were characterized by a gradual decline in abundance over time. Comparisons of detailed nannofossil assemblage records at the Cicogna section and at ODP Site 1262 support the idea that variations in relative and absolute abundance, even some minor ones, were globally synchronous. An obvious link is through climate forcing and carbon cycling, although precise linkages to changes in δ13C records and oceanographic change will need additional work.
Conductas agresivas y de Bullying desde la perspectiva de actividad física, lugar de residencia y género en adolescentes de Granada
Authors: Zurita Ortega Félix , Vilches Aznar José Mª , Padial Ruz Rosario , Perez Cortes Antonio J. , Martínez Martínez Asunción
Published: September 2015

En este trabajo de investigación se tiene como objetivo analizar y establecer los índices de Victimización, Bullying y Conducta Violenta y su posible relación con el género, residencia habitual y práctica de A.F de adolescentes de 13 a 17 años de Granada (España). La participación de un total de 2.273 adolescentes permitió el registro y evaluación de las variables Victimización (escala de Victimización en la Escuela), Conducta Violenta (medida con la escala de Conducta Violenta en la Escuela), Bullying, género, lugar de residencia y práctica de Actividad Física. Los resultados mostraron que los adolescentes en más de la mitad de los casos indicaron que sin ser agresores sí que fueron testigos de casos de Bullying, también se detectó que los niveles de Agresividad (Manifiesta y Relacional) eran similares, mientras que la Victimización de tipo Verbal era la más usual. Asimismo los jóvenes residentes fuera del contexto familiar eran más acosadores y habían sufrido más acoso y tenían mayores índices de agresividad y victimización. La práctica de Actividad Física era más asidua en varones, y estos se caracterizaban por tener mayor agresividad manifiesta y un índice superior de victimización física, encontrándose más acosadores entre los varones y siendo estos más testigos de hechos violentos, mientras las chicas lo sufrían más y a la vez percibían menos situaciones de Bullying. Como principal recomendación indicamos la necesidad de estudiar con mayor profundidad a la población deportivamente activa para intentar dilucidar la casuística de estos resultados.
Ectopic Intrathoracic Hepatic Tissue and Accessory Lung Lobe Aplasia in a Dog
Authors: Lande Rachel , Dvorak Laura , Gardiner David W. , Bahr Anne
Published: September 2015

A 6 yr old male Yorkshire terrier was presented for an ~6 yr history of progressive cough and dyspnea. Thoracic radiographs revealed a 6 cm diameter mass within the right caudal thorax. Thoracic ultrasound identified an intrathoracic mass ultrasonographically consistent with liver tissue and a chronic diaphragmatic hernia was suspected. Exploratory laparotomy was performed, but no evidence of a diaphragmatic hernia was identified. Thoracic exploration identified abnormal lung parenchyma. The accessory lung lobe was removed using a stapling devise near its base. The consolidated mass had the gross appearance of liver and was histologically identified as ectopic hepatic tissue. Ectopic hepatic tissue, unlike ectopic splenic and pancreatic tissue, is rare and generally has a subdiaphragmatic distribution. This solitary case report demonstrates that ectopic intrathoracic hepatic tissue should be considered a differential diagnosis for a caudal mediastinal mass.
Ontological Assumptions in Techno-Anthropological Explorations of Online Dialogue through Information Systems
Authors: Otrel-Cass Kathrin , Andrule Kristine ,   Philosophy Documentation Center
Published: September 2015

With the widespread infusion of online technology there has been an increase in various studies investigating the practices in online communities including also philosophical perspectives. What those debates have in common is that they call for more critical thinking about the theory of online communication. Drawing on Techno-Anthropological research perspectives, our interest is placed on exploring and identifying human interactions and technology in intersectional spaces. This article explores information systems that allow for interchanges of different users. We discuss ontological assumptions that focus on understanding the kind of dialogue that can be captured between different expert groups when they utilize information systems. We present the notion of ‘dialogic’ by Mikhail Bakhtin and contextualize it through an analysis of online dialogue. Dialogic or ‘conversation and inquiry’ is discussed as being mediated through human relationships. Acknowledging the existence of at least two voices the underlying differences between dialogue partners are highlighted.
Estimation of Water Quality Parameters With Data‐Driven Model
Authors: Sattari Mohammad Taghi , Joudi Ali Rezazadeh , Kusiak Andrew
Published: September 2015

Electrical conductivity and total dissolved solids are considered important parameters in determining quality of drinking and agricultural water because they directly represent total salt concentration in the water. Increases in these parameter values indicate a reduction in water quality. In this study, estimation of the two parameters in the Lighvan Chay River located in Eastern Azerbaijan, Iran, is studied using the k‐nearest neighbors algorithm and support vector regression. Different sets of chemical parameters (i.e., phosphorus, chlorine, calcium, magnesium, sodium, sodium adsorption ratio, sulfate, bicarbonate) were considered as inputs while the total dissolved solids and electrical conductivity were the outputs. Three statistics—coefficient of determination (R2), root mean square error, and mean absolute error—were used to verify accuracy of these models. Comparison of the results showed that both algorithms accurately estimated the total dissolved solids and electrical conductivity, but the support vector regression model is recommended because of better performance.
Network Features and Processes as Determinants of Organizational Interaction during Extreme Events
Authors: Siciliano Michael D. , Wukich Clayton
Published: September 2015

Despite the widely acknowledged importance of collaboration among participants in governance networks, a limited number of studies have attempted to statistically model the processes by which those networks form. In this article, we explore a range of network features and processes and measure their influence on network formation. We examine the case of Hurricane Katrina and employ exponential random graph models to identify the drivers of network formation in extreme events. We find that both the attributes of individual organizations and endogenous network processes affect organizational collaboration. Understanding these factors is important because the structure of the response network influences information flow, resource exchange, and performance.
Observations of the summer breakup of an Arctic sea ice cover
Authors: Arntsen Alexandra E. , Song Arnold J. , Perovich Donald K. , Richter‐Menge Jacqueline A.
Published: September 2015

The Arctic sea ice cover evolves dramatically through the summer melt season. Floe size distribution (FSD) is a critical parameter used to examine this change as the ice cover transitions from large rectilinear plates in spring to an ensemble of discrete rounded floes by midsummer. The FSD at a given time impacts the dynamic and thermodynamic behavior of the ice cover. Focusing on the seasonal marginal ice zone in the Beaufort and Chukchi Seas from May to September 2014, we present qualitative and quantitative results derived from National Technical Means high‐resolution imagery and supported by ice mass balance buoy data. Results indicate that as melt accelerates, floe breaking pattern, and therefore FSD, is heavily influenced by the distribution of melt ponds. Discrete element model results using morphological conditions derived from analyzed satellite imagery confirmed that breaking occurs along ponds and perpendicular to applied stress.
Unraveling the missing link of ENSO control over the Indian monsoon rainfall
Authors: Dwivedi Suneet , Goswami B. N. , Kucharski Fred
Published: September 2015

Using long daily rainfall (113 years) data, clear evidence of modulation of the statistics of subseasonal active and break spells of the Indian summer monsoon rainfall (ISMR) by the El Niño–Southern Oscillation (ENSO) is unraveled. We show that during the El Niño (La Nina) years, the frequency of longer break (active) spells and shorter active (break) spells increases substantially, while the frequency of shorter breaks (active) and longer active (break) spells decreases compared to ENSO neutral years. It is shown that the large‐scale teleconnection through which ENSO weakens (strengthens) the ISMR through shortening (lengthening) of the length of rainy season (LRS) also creates a background for modulation of the statistics of subseasonal spells leading to a further reduction (increase) in the ISMR during El Niño (La Niña) years. Our findings indicate that the “statistics of subseasonal spells” is predictable, brightening the prospect of seasonal prediction of the ISMR.
Quantifying contributions of model processes to the surface temperature bias in FGOALS‐g2
Authors: Liu Bo , Zhou Tianjun , Lu Jianhua
Published: September 2015

To quantify the annual mean surface temperature bias due to various processes in Flexible Global Ocean‐Atmosphere‐Land‐System model, Grid point version 2 (FGOALS‐g2), the climate feedback‐response analysis method (CFRAM) is used to isolate contributions from both radiative and nonradiative processes in the model by comparing the model simulation with ERA‐Interim reanalysis. The observed surface temperature bias is decomposed into seven partial temperature biases associated with surface albedo, water vapor, cloud, both surface sensible and latent heat fluxes, land/ocean heat transport processes, and atmospheric transport processes. The global mean cold bias (−1.39 K) is mostly attributed to surface albedo and land/ocean heat transport processes while surface latent heat fluxes tend to weaken this bias. Cloud‐induced bias is dominated by shortwave cloud radiative effect (SWCRE) over low‐latitudes and longwave cloud radiative effect (LWCRE) over high latitudes. The mixed layer depth (MLD) bias is consistent with the bias due to ocean heat transport over North Pacific, North Atlantic, and the Southern Ocean. On global scale, contributions of radiative processes and nonradiative processes to the total observed cold bias are comparable, but tend to compensate each other over most regions except for the northern high latitudes. We suggest that the improvements in tropical clouds in the model may significantly decrease the global temperature bias through the interaction between clouds and circulation.
Global sensitivity of parabolic equation radar wave propagation simulation to sea state and atmospheric refractivity structure
Authors: Lentini N. E. , Hackett E. E.
Published: September 2015

Inadequate representation of the environment is a limitation for prediction of radar system performance as well as for validation of propagation codes. To improve understanding of how different environmental effects/parameters compete and compare, this study examines the sensitivity of radar wave propagation to a suite of environmental parameters for low grazing angle near‐surface radar systems at 3–15 GHz at horizontal and vertical polarizations. A global sensitivity analysis method is used, which accounts for parameter interactions, and propagation is modeled using the parabolic equation method. Environmental parameters examined include eight sea state parameters and eight parameters characterizing the vertical structure and character of range‐independent refractivity profiles. The relative importance of parameters varies more with frequency than polarization, and parameter interactions are found to be significant. Atmospheric mixed layer parameters are found to be the most sensitive, particularly the thickness of the mixed layer. The most significant ocean surface parameter is swell period, although sea directionality is important at 3 GHz and sea surface roughness and salinity are important at 9 and 15 GHz. Because of the spatial variability of sensitivity throughout the domain, regional analysis is performed to determine the most important parameters in different regions of the domain (1000 m in altitude and 60 km in range). These regional sensitivity results, along with those for the whole domain, provide guidance on prioritization of environmental characterization in numerical weather prediction and inversion studies (e.g., refractivity from clutter studies), which are two common methods currently used to address environmental effects on propagation.
Stability of an Amorphous TiCuNi Alloy Subjected to High‐Pressure Torsion at Different Temperatures
Authors: Gunderov Dmitry , Slesarenko Viacheslav , Lukyanov Alexander , Churakova Anna , Boltynjuk Evgeniy , Pushin Vladinir , Ubyivovk Evgeniy , Shelyakov Alexander , Valiev Ruslan
Published: September 2015

The amorphous melt‐spun (MS) Ti50Ni25Cu25 alloy is subjected to high‐pressure torsion (HPT) at temperatures of 20‐150 °C. The bright‐field (BF) TEM images of the alloy change as a result of HPT processing, the view of the bright‐field image depends on the temperature of HPT processing. HPT processing leads to a decrease in the energy of structural relaxation during heating up to 400 °C, in comparison with the initial MS ribbons. The temperature of crystallization of the MS Ti50Ni25Cu25 alloy decreases after HPT processing by 40–20 °C (depends on the temperature of HPT processing). In the MS Ti50Ni25Cu25 alloy, HPT processing and subsequent annealing produces noticeably finer grains than annealing at 450 °C of the initial MS alloy. Consequently, HPT processing alters the crystallization kinetics of the MS Ti50Ni25Cu25 alloy.
Tuning Hydrogel Mechanics Using the Hofmeister Effect
Authors: Jaspers Maarten , Rowan Alan E. , Kouwer Paul H. J.
Published: September 2015

The mechanical properties of hydrogels are commonly modified by changing the concentration of the molecular components. This approach, however, does not only change hydrogel mechanics, but also the microstructure, which in turn alters the macroscopic properties of the gel. Here, the Hofmeister effect is used to change the thermoresponsiveness of polyisocyanide hydrogels. In contrast to previous Hofmeister studies, the effect is used to change the phase transition temperatures and to tailor the mechanics of the thermoresponsive (semiflexible) polymer gels. It is demonstrated that the gel stiffness can be manipulated over more than two orders of magnitude by the addition of salts. Surprisingly, the microstructure of the gels does not change upon salt addition, demonstrating that the Hofmeister effect provides an excellent route to change the mechanical properties without distorting other influential parameters of the gel.
Vertically Aligned WS2 Nanosheets for Water Splitting
Authors: Yang Yang , Fei Huilong , Ruan Gedeng , Li Yilun , Tour James M.
Published: September 2015

Vertically aligned WS2 (VAWS2) nanosheet films are prepared using a lithium based anodization electrolyte to fabricate WO3 films followed by sulfurization. The VAWS2 synthesized here is self‐organized as a conformal structure to expose active edge sites for water splitting. These vertically aligned nanosheets are composed of exfoliated WS2 to provide abundant active edges for catalytic reactions. Hydrogen evolution activity of the VAWS2 is demonstrated to show high catalytic current, low onset overpotential and small Tafel slope. By certain measures, this VAWS2 nanosheet film outperforms some of the state‐of‐the‐art hydrogen evolution reaction (HER) catalysts, which opens up a new pathway to simply and scalably fabricate high‐performance water electrolysis catalysts.
3‐Naphthylindole Construction by Rhodium(II)‐Catalyzed Regioselective Direct Arylation of Indoles with 1‐Diazonaphthalen‐2‐(1H)‐ones
Authors: Baral Ek Raj , Lee Yong Rok , Kim Sung Hong
Published: September 2015

The regioselective direct 3‐arylation of indoles with 1‐diazonaphthalen‐2‐(1H)‐ones was developed by means of a rhodium(II) pivalate‐catalyzed cross‐coupling reaction. This procedure provided a variety of novel 3‐naphthylindoles in high yield. The direct coupling of benzofuran, pyrrole or furan with 1‐diazonaphthalen‐2‐(1H)‐ones afforded 2‐ or 3‐naphthyl substituted heterocycles.

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On‐Column Reaction Set‐Up for High‐Throughput Screenings and Mechanistic Investigations
Authors: Stockinger Skrollan , Troendlin Johannes , Rominger Frank , Trapp Oliver
Published: September 2015

A screening platform, which offers a high‐throughput approach as well as an easy investigation of kinetic isotope effects, applicable to a wide range of reactions is presented. To illustrate the high potential of this approach, the asymmetric transfer hydrogenation of methyl benzoylformate with copper(II) bis(oxazoline) and Hantzsch ester was examined. Accordingly, the enantioselectivities of the reaction performed on‐column in a microcapillary were comparable to standard reaction conditions, however, we were able achieve catalysis and analysis in a single step in less than 30 min. The throughput can be increased by simultaneous investigation of different substrates without increasing the overall analysis time. Use of di‐deuterated Hantzsch ester allowed us to investigate the kinetic isotope effect of the transfer hydrogenation reaction only requiring a minute amount of the deuterated transfer hydrogenation reagent. Hence we were able to get further insights into the mechanism of the asymmetric transfer hydrogenation using Hantzsch ester as hydrogen source. The here presented technique is broadly applicable to study isotope effects on a very small scale, which is a rapid and an inexpensive alternative compared to conventional experiments.

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Enantioselective Palladium‐Catalyzed Heck–Heck Cascade Reactions: Ready Access to the Tetracyclic Core of Lycorane Alkaloids
Authors: Coya Estibaliz , Sotomayor Nuria , Lete Esther
Published: September 2015

A rapid and efficient access to a wide variety of enantiomerically enriched C‐11b substituted lycorane analogues can be achieved via a catalytic asymmetric Heck–Heck 6‐exo/6‐endo cascade reaction in the presence of (R)‐BINAP.

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Brønsted Acid‐Promoted Cascade Alkylation/Cyclization of Pyrroles with N,N‐Dimethylaminomethyleneglutaconic Acid Dinitrile: A Concise Route to Cyclopenta[b]pyrroles
Authors: Wu Kaikai , Wu Ping , Chen Jiping , Sun Chenglin , Yu Zhengkun
Published: September 2015

A Brønsted acid (p‐TsOH⋅H2O) promoted alkylation/cyclization cascade reaction of pyrroles with N,N‐dimethylaminomethyleneglutaconic acid dinitrile was efficiently realized to afford functionalized cyclopenta[b]pyrroles with excellent diastereoselectivity. Deamination of the corresponding ammonium salts of the cyclopenta[b]pyrroles with methyl iodide led to dihydrocyclopenta[c]pyrroles. The cascade reaction pathway was confirmed by isolation and transformation of the reaction intermediate, i.e., the 2‐alkylated pyrrole.

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Rhodium(III)‐Catalyzed Redox‐Neutral CH Annulation of Arylnitrones and Alkynes for the Synthesis of Indole Derivatives
Authors: Zhou Zhi , Liu Guixia , Chen Yan , Lu Xiyan
Published: September 2015

By using a nitrone as the oxidizing directing group, a mild, practical and efficient rhodium(III)‐catalyzed CH functionalization for the synthesis of indole derivatives has been developed. This reaction obviates the need for an external oxidant and shows good functional group tolerance. The employment of a sterically hindered Mes group on the carbon center of the nitrone is crucial to produce indoles in high yield.

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Synthesis, Characterization, and Optical Performance of a Novel Fluorescent Waterborne Polyurethane
Authors: Tian Saiqi , Zhang Peikun , Fan Haojun , Chen Yi , Yan Jun , Shi Bi
Published: September 2015

A fluorescent fluorescent waterborne polyurethane (FWPU) was synthesized by conjugating fluorescer, isodium 4,4′‐bis[4‐anilino‐6‐hydroxyethylamino‐6‐(2‐choloronilino‐1,3,5‐triazin‐2‐yl)amino]stilbene‐2,2′‐disulphonate (RSW), into polyurethane backbone as a chain extender. The expected structure of FWPU was confirmed by Fourier transform infrared, 1H nuclear magnetic resonance, and UV−vis spectrophotometer, and the effect of fluorescer content, temperature, as well as quencher on the fluorescence performances of FWPU was investigated in detail. Results reveal that covalently conjugation has unconspicuous effect on optical performance, and FWPU shows similar fluorescence intensity to fluorescer RSW except for a red shift of about 10 nm in maximum absorption wavelengths. Further study finds that there is a positive correlation between the concentration of fluorescer and the fluorescence intensity of FWPU; however, the opposite effect is obtained when the concentration exceeds 1 × 10−5 mol/L, which is attributed to the concentration self‐quenching. Although high temperature will decrease the intensity of fluorescence, the fluorescence components in FWPU shows high resistance to fluorescence quencher and thermal decomposition as a consequence of chemical combination with the polymer chain.
Immunophenotypic parameters and RBC alloimmunization in children with sickle cell disease on chronic transfusion
Authors: Nickel Robert S. , Horan John T. , Fasano Ross M. , Meyer Erin , Josephson Cassandra D. , Winkler Anne M. , Yee Marianne E.M. , Kean Leslie S. , Hendrickson Jeanne E.
Published: September 2015

Alloimmunization against red blood cell (RBC) antigens is a cause of morbidity and mortality in transfused patients with sickle cell disease (SCD). To investigate distinguishing characteristics of patients who develop RBC alloantibodies after transfusion (responders) versus those who do not (non‐responders), a cross‐sectional study of 90 children with SCD on chronic RBC transfusion therapy at a single institution was conducted in which 18 immune parameters (including T and B cell subsets) were tested via flow cytometry, and medical records were reviewed. RBC alloimmunization was present in 26/90 (29%) patients, with anti‐E, K, and C among the most commonly detected alloantibodies despite prophylactic matching for these antigens at the study institution. In addition, RBC autoantibodies had been detected in 18/26 (69%) of alloimmunized versus 7/64 (11%) of non‐alloimmunized patients (P < 0.0001). Alloimmunized patients were significantly older (median 13.0 years vs. 10.7 years, P = 0.010) and had more RBC unit exposures (median 148 U vs. 82 U, P = 0.020) than non‐alloimmunized patients. Sex, age at initiation of chronic transfusion, splenectomy, stroke, and transfusion outside of the study institution were not significantly associated with RBC alloimmunization. Alloimmunized patients had a significantly increased percentage of CD4+ T memory cells compared to non‐alloimmunized patients (57% vs. 49%, P = 0.0047), with no other significant differences in immune cell subsets or laboratory values detected between these groups. Additional research of RBC alloimmunization is needed to optimize transfusion therapy and to develop strategies to prevent alloimmunization. Am. J. Hematol. 90:1135–1141, 2015. © 2015 Wiley Periodicals, Inc.
Trends of occupational fatalities involving machines, United States, 1992–2010
Authors: Marsh Suzanne M. , Fosbroke David E.
Published: September 2015

Background

This paper describes trends of occupational machine‐related fatalities from 1992–2010. We examine temporal patterns by worker demographics, machine types (e.g., stationary, mobile), and industries.

Methods

We analyzed fatalities from Census of Fatal Occupational Injuries data provided by the Bureau of Labor Statistics to the National Institute for Occupational Safety and Health. We used injury source to identify machine‐related incidents and Poisson regression to assess trends over the 19‐year period.

Results

There was an average annual decrease of 2.8% in overall machine‐related fatality rates from 1992 through 2010. Mobile machine‐related fatality rates decreased an average of 2.6% annually and stationary machine‐related rates decreased an average of 3.5% annually. Groups that continued to be at high risk included older workers; self‐employed; and workers in agriculture/forestry/fishing, construction, and mining.

Conclusion

Addressing dangers posed by tractors, excavators, and other mobile machines needs to continue. High‐risk worker groups should receive targeted information on machine safety. Am. J. Ind. Med. 58:1160–1173, 2015. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.