bluuebunny/crossref_metadata_2025 huggingface dataset:
Downscaling de variables climáticas a partir del reanálisis NCEP/NCAR en el sudoeste de la provincia de Buenos Aires (Argentina)
Authors: Ferrelli Federico , Bustos María Luján , Piccolo María Cintia , Huamantinco Cisneros María Andrea , Perillo Gerardo Miguel Eduardo
Published: February 2017

El objetivo de este estudio fue proponer una manera sencilla de utilizar la información del Reanalysis (NCEP/NCAR) para estimar la temperatura del aire, la humedad relativa y las precipitaciones en aquellas regiones con escasez de registros in situ. El área de estudio correspondió al sudoeste de la provincia de Buenos Aires, Argentina. Se aplicaron técnicas estadísticas sobre la información de nueve estaciones meteorológicas y datos estimados con el Reanalysis. En períodos cortos (10 años), el mejor ajuste se presentó para la temperatura del aire, específicamente en otoño y primavera, mientras que la humedad relativa y la precipitación manifestaron algunas diferencias. Por otro lado, en períodos largos (30 años) los datos estimados fueron útiles para realizar un estudio climático ya que se presentó una alta correlación entre los datos in situ y los del Reanalysis.
Testing the Effort Models' tightrope hypothesis in simultaneous interpreting - A contribution
Authors: Gile Daniel
Published: February 2017

In a sample of 10 professionals interpreting the same source speech in the simultaneous mode, errors and omissions (e/o’s) were found to affect different source-speech seg-ments, and a large proportion among them were only made by a small proportion of the subjects. In a repeat performance, there were some new e/o’s in the second version when the same interpreters had interpreted the same segments correctly in the first version. These findings strengthen the Effort Models’ “tightrope hypothesis” that many e/o’s are due not to the intrinsic difficulty of the corresponding source-speech segments, but to the interpreters working close to processing capacity saturation, which makes them vulnerable to even small variations in the available processing capacity for each interpreting component.
The never changing metaphors - introduction to thematic section
Authors: Grevy Carlo
Published: February 2017

No abstract.
Metaphors, Visual Blends and the Ideology of Information Technology
Authors: Rohrer Tim
Published: February 2017

In this article I argue from linguistic and visual evidence that the information highway metaphor is having tremendous ideological effects in shaping U.S. politics over technology. I apply Lakoff and Johnson’s theory of conceptual metaphor to the linguistic and visual evidence, but then argue that Fauconnier and Turner’s theory of conceptual blending is useful to explain the visual and linguistic evidence in its full complexity. I conclude by summarizing the ways in which current ideological uses of conceptual metaphors and conceptual blends are assimilating the older innovative software design metaphors for operating systems.
Uticaj starosti nosilja lakog linijskog hibrida kokoši na osobine kvaliteta jaja
Authors: Pandurević Tatjana , Mitrović Sreten , Đekić Vera , Ristanović Bojana
Published: February 2017

U cilju utvrđivanja osobina kvaliteta konzumnih jaja lakog linijskog hibrida Lohmann Brown sprovedena su istraživanja na živinarskoj farmi privatnog gazdinstva «Rakić komerc» doo, Batković, Bijeljina, Republika Srpska (BiH). U toku produkcije jaja posebna pažnja je obraćena na četiri glavne proizvodne faze, i to: 20. nedelja – SN20 (početak nosivosti), 28. nedelja - SN28 („pik“ maksimum), 48. nedelja – SN48 (sredina) i 72. nedelja starosti nosilja – SN72 (kraj proizvodnog ciklusa). U navedenim periodima, metodom slučajnog uzorka uzet je odgovarajući broj nosilja, odnosno jaja za istraživanja, analizu i statističku obradu utvrđenih podataka za ispitivane parametre. Pored mase, utvrđene su pojedine osobine kvaliteta jaja: masa jaja (g), dužina jajeta (mm), širina jajeta (mm), indeks oblika jajeta (%), boja ljuske (poen), čistoća ljuske (poen) i boja žumanca (1-15 Roshe, pri starosnom dobu nosilja (SN20-72). Rezultati istraživanja pokazuju da razlike u prosječnoj masi jaja porijeklom od različite starosti nosilja su bile statistički signifikantne (P < 0,001). Analizirano komercijalno jato nosilja u proizvodnji konzumnih jaja, posmatrano u cjelini, ostvarilo je zadovoljavajuće rezultate kada su u pitanju parametri kvaliteta.
Značaj silaže strnih žita u ishrani goveda
Authors: Radivojević Mihailo , Stojić Petar , Miletić Aleksandar , М. Urošević Milivoje , Drobnjak Darko
Published: February 2017

Intenzivno mlečno govedarstvo, opravdano se karakteriše kao industrijska proizvodnja. Na Balkanu, u velikoj meri temelji se na brojnim saznanjima iz zemalja intenzivnog stočarstva, kako u oblasti selekcije tako i ishrane. Kao i u SAD najproduktivnija rasa je holštajn, a najznačajnija hraniva su kukuruzna silaža i seno, odnosno senaža, lucerke. Ipak, svedoci smo klimatskih promena koje ne pogoduju lucerki a još manje kukuruzu, naročito u uslovima suvog ratrenja. Sve je teže realizovati proizvodnju dovoljnih količina kvalitetne silaže kukuruza. Pored toga, energetska kriza koja će u decenijama pred nama biti još drastičnija, daje kukuruzu i dodatni značaj, kao dragocenoj sirovini za dobijanje etanola. To nameće potrebu iznalaženja drugih biljnih kultura pogodnih za proizvodnju kvalitetne silaže. Upravo zato, istraživanje mogućnosti upotrebe silaža strnih žita u ishrani preživara, sve više dobija na značaju, a cilj ovog rada je pregled značajnijih iskustava i rezultata istraživanja u toj oblasti. Rad je metodološki zasnovan na prikupljanju i analizi podataka iz literature.
Genetic diversity and differentiation in reef-buildingMilleporaspecies, as revealed by cross-species amplification of fifteen novel microsatellite loci
Authors: Dubé Caroline E. , Planes Serge , Zhou Yuxiang , Berteaux-Lecellier Véronique , Boissin Emilie
Published: February 2017

Quantifying the genetic diversity in natural populations is crucial to address ecological and evolutionary questions. Despite recent advances in whole-genome sequencing, microsatellite markers have remained one of the most powerful tools for a myriad of population genetic approaches. Here, we used the 454 sequencing technique to develop microsatellite loci in the fire coralMillepora platyphylla, an important reef-builder of Indo-Pacific reefs.We tested the cross-species amplification of these loci in five other species of the genusMilleporaand analysed its success in correlation with the genetic distances between species using mitochondrial 16S sequences. We succeeded in discovering fifteen microsatellite loci in our target speciesM. platyphylla,among which twelve were polymorphic with 2–13 alleles and a mean observed heterozygosity of 0.411. Cross-species amplification in the five otherMilleporaspecies revealed a high probability of amplification success (71%) and polymorphism (59%) of the loci. Our results show no evidence of decreased heterozygosity with increasing genetic distance. However, only one locus enabled measures of genetic diversity in the Caribbean speciesM. complanatadue to high proportions of null alleles for most of the microsatellites. This result indicates that our novel markers may only be useful for the Indo-Pacific species ofMillepora.Measures of genetic diversity revealed significant linkage disequilibrium, moderate levels of observed heterozygosity (0.323–0.496) and heterozygote deficiencies for the Indo-Pacific species. The accessibility to new polymorphic microsatellite markers for hydrozoanMilleporaspecies creates new opportunities for future research on processes driving the complexity of their colonisation success on many Indo-Pacific reefs.
Eotaria citrica, sp. nov., a new stem otariid from the “Topanga” formation of Southern California
Authors: Velez-Juarbe Jorge
Published: February 2017

A new taxon of stem otariid,Eotaria citricasp. nov., is described from the upper Burdigalian to lower Langhian “Topanga” formation of Orange County, California. The new species is described from mandibular and dental remains that show a unique combination of plesiomorphic and derived characters. Specifically, it is characterized by having trenchant and prominent paraconid cusps in p3–m1, lingual cingula of p2–4 with faint crenulations, premolars and molars with vestigial metaconid, bilobed root of m2 and a genial tuberosity located under p3. Furthermore, additional material of the contemporaneousEotaria cryptais described, providing new information on the morphology of this taxon. Both species ofEotariarepresent the earliest stem otariids, reinforcing the hypothesis that the group originated in the north Eastern Pacific Region. At present, the “Topanga” Fm. pinniped fauna includesEotaria citrica,Eotaria crypta, the desmatophocidAllodesmussp., the odobenidsNeotheriumsp.,Pelagiarctossp. and includes the oldest records of crown pinnipeds in California. Overall this pinniped fauna is similar to the nearly contemporaneous Sharktooth Hill bonebed. However, unambiguous records ofEotariaare still missing from Sharktooth Hill. This absence may be due to taphonomic or paleoenvironmental factors. The new “Topanga” record presented here was integrated into an overview of the late Oligocene through early Pleistocene pinniped faunas of Southern California. The results show an overall increase in body size over time until the Pleistocene. Furthermore, desmatophocids were the largest pinnipeds during the middle Miocene, but were extinct by the beginning of the late Miocene. Odobenids diversified and became the dominant pinnipeds in late Miocene through Pleistocene assemblages, usually approaching or exceeding 3 m in body length, while otariids remained as the smallest taxa. This pattern contrasts with modern assemblages, in which the phocidMirounga angustirostrisis the largest pinniped taxon in the region, odobenids are extinct and medium and small size ranges are occupied by otariids or other phocids.
Conformational dynamics of the rotary subunit F in the A3B3DF complex of Methanosarcina mazei Gö1 A‐ATP synthase monitored by single‐molecule FRET
Authors: Singh Dhirendra , Sielaff Hendrik , Börsch Michael , Grüber Gerhard
Published: February 2017

In archaea the A1AO ATP synthase uses a transmembrane electrochemical potential to generate ATP, while the soluble A1 domain (subunits A3B3DF) alone can hydrolyse ATP. The three nucleotide‐binding AB pairs form a barrel‐like structure with a central orifice that hosts the rotating central stalk subunits DF. ATP binding, hydrolysis and product release cause a conformational change inside the A:B‐interface, which enforces the rotation of subunits DF. Recently, we reported that subunit F is a stimulator of ATPase activity. Here, we investigated the nucleotide‐dependent conformational changes of subunit F relative to subunit D during ATP hydrolysis in the A3B3DF complex of the Methanosarcina mazei Gö1 A‐ATP synthase using single‐molecule Förster resonance energy transfer. We found two conformations for subunit F during ATP hydrolysis.
Aerosol‐driven increase in Arctic sea ice over the middle of the twentieth century
Authors: Gagné Marie‐Ève , Fyfe John C. , Gillett Nathan P. , Polyakov Igor V. , Flato Gregory M.
Published: February 2017

Updated observational data sets without climatological infilling show that there was an increase in sea ice concentration in the eastern Arctic between 1950 and 1975, contrary to earlier climatology infilled observational data sets that show weak interannual variations during that time period. We here present climate model simulations showing that this observed sea ice concentration increase was primarily a consequence of cooling induced by increasing anthropogenic aerosols and natural forcing. Indeed, sulphur dioxide emissions, which lead to the formation of sulphate aerosols, peaked around 1980 causing a sharp increase in the burden of sulphate between the 1950s and 1970s; but since 1980, the burden has dropped. Our climate model simulations show that the cooling contribution of aerosols offset the warming effect of increasing greenhouse gases over the midtwentieth century resulting in the expansion of the Arctic sea ice cover. These results challenge the perception that Arctic sea ice extent was unperturbed by human influence until the 1970s, suggesting instead that it exhibited earlier forced multidecadal variations, with implications for our understanding of impacts and adaptation in human and natural Arctic systems.
Use and misuse of large‐density asymptotics in the reaction‐infiltration instability
Authors: Ladd Anthony J. C. , Szymczak Piotr
Published: February 2017

Analyzing the dissolution of rocks and other porous materials is simplified by the large disparity between mineral and reactant concentrations. In essence, the porosity remains frozen on the time scale of the reactant transport, which can then be treated as a quasi‐stationary process. This conceptual idea can be derived mathematically using asymptotic methods, which show that the length scales in the system are, to a first approximation, independent of the ratio of reactant and mineral concentrations. Nevertheless, in a growing number of papers on dissolutional instabilities, the reactant‐mineral concentration ratio has been incorrectly linked to the thickness of the dissolution front. In this paper we critically review the application of asymptotic methods to the reaction‐infiltration instability. In particular, we discuss the limited validity of the thin‐front or “Stefan” limit, where the interface between dissolved and undissolved mineral is sharp.
Effect of volcanic dykes on coastal groundwater flow and saltwater intrusion: A field‐scale multiphysics approach and parameter evaluation
Authors: Comte J.‐C. , Wilson C. , Ofterdinger U. , González‐Quirós A.
Published: February 2017

Volcanic dykes are common discrete heterogeneities in aquifers; however, there is a lack of field examples of, and methodologies for, comprehensive in situ characterization of their properties with respect to groundwater flow and solute transport. We have applied an integrated multiphysics approach to quantify the effect of dolerite dykes on saltwater intrusion in a coastal sandstone aquifer. The approach involved ground geophysical imaging (passive magnetics and electrical resistivity tomography), well hydraulic testing, and tidal propagation analysis, which provided constraints on the geometry of the dyke network, the subsurface saltwater distribution, and the sandstone hydrodynamic properties and connectivity. A three‐dimensional variable‐density groundwater model coupled with a resistivity model was further calibrated using groundwater and geophysical observations. A good agreement of model simulations with tide‐induced head fluctuations, geophysically derived pore water salinities, and measured apparent resistivities was obtained when dykes' hydraulic conductivity, storativity, and effective porosity are respectively about 3, 1, and 1 orders of magnitude lower than the host aquifer. The presence of the dykes results in barrier‐like alterations of groundwater flow and saltwater intrusion. Preferential flow paths occur parallel to observed dyke orientations. Freshwater inflows from upland recharge areas concentrate on the land‐facing side of the dykes and saltwater penetration is higher on their sea‐facing side. This has major implications for managing groundwater resources in dyke‐intruded aquifers, including in coastal and island regions and provides wider insights on preferential pathways of groundwater flow and transport in highly heterogeneous aquifer systems.
CO2‐vegetation feedbacks and other climate changes implicated in reducing base flow
Authors: Trancoso Ralph , Larsen Joshua R. , McVicar Tim R. , Phinn Stuart R. , McAlpine Clive A.
Published: February 2017

Changes in the hydrological cycle have a significant impact in water limited environments. Globally, some of these regions are experiencing declining precipitation yet are simultaneously becoming greener, partly due to vegetation feedbacks associated with increasing atmospheric CO2 concentrations. Reduced precipitation together with increasing rates of actual evapotranspiration diminishes streamflow, especially base flow, a critical freshwater dry‐season resource. Here we assess recent changes in base flow in Australia from 1981–2013 and 1950–2013 and separate the contribution of precipitation, potential evapotranspiration, and other factors on base flow trends. Our findings reveal that these other factors influencing the base flow trends are best explained by an increase in photosynthetic activity. These results provide the first robust observational evidence that increasing atmospheric CO2 and its associated vegetation feedbacks are reducing base flow in addition to other climatic impacts. These findings have broad implications for water resource management, especially in the world's water limited regions.
Laser Powder Bed Fusion – Materials Issues and Optimized Processing Parameters for Tool steels, AlSiMg‐ and CuCrZr‐Alloys
Authors: Buchmayr Bruno , Panzl Gerhard , Walzl Alexander , Wallis Christopher
Published: February 2017

Laser Powder Bed Fusion (L‐PBF) is the main technology for additive manufacturing of metallic components and is primarily used for rapid prototyping and tooling in cases with very complex geometry or lightweight design and small quantities. There are manifold influencing parameters, which need to be optimized in order to build components with suitable properties. The paper deals with three distinct application fields, like the development of new tool steel grades for injection molds, light weight design using aluminum alloys with optimized post‐weld heat treatment as well as production of copper alloys without porosity. The most sensitive process parameters are displayed and the multi‐layered components are characterized using light and high‐resolution microscopy as well as mechanical testing.
Intermetallic β‐Solidifying γ‐TiAl Based Alloys − From Fundamental Research to Application
Authors: Mayer Svea , Erdely Petra , Fischer Franz Dieter , Holec David , Kastenhuber Michael , Klein Thomas , Clemens Helmut
Published: February 2017

Intermetallic titanium aluminides based on the ordered γ‐TiAl phase have gained increasing interest as innovative high‐temperature light‐weight structural materials. They have found application in aerospace and automotive industries and are still subject of worldwide research and development activities. Their attractive properties perfectly match the engine manufacturers’ demands. This review, bridges the gap from the development of the TNM alloy through structural characterization with sophisticated in and ex situ methods, engineering properties, manufacturing, and processing technologies to all aspects of application. Because one thing is clear, the material still has great potential.
Advanced Structural Materials by Bioinspiration
Authors: Libonati Flavia , Buehler Markus J.
Published: February 2017

In the quest of increasing safety and efficiency in structural applications, learning from natural materials can be a promising approach. Nature has evolved for billions of years to develop elaborate strategies, achieving optimal material solutions. A brief review of exemplar natural materials is provided here, with a focus on their multiscale structures. The design motifs, common to biological structural materials, are summarized, with a highlight on the structure‐property relationship. A review of recent advancement in the manufacturing of bio‐inspired composites is given, followed by recent and successful case studies. Finally, a critical discussion, highlighting the limitations of the current techniques, and prospecting the future challenges for the design of novel materials for engineering applications.
In Silico Design of Optimal Dissolution Kinetics of Fe‐Doped ZnO Nanoparticles Results in Cancer‐Specific Toxicity in a Preclinical Rodent Model
Authors: Manshian Bella B. , Pokhrel Suman , Himmelreich Uwe , Tämm Kaido , Sikk Lauri , Fernández Alberto , Rallo Robert , Tamm Tarmo , Mädler Lutz , Soenen Stefaan J.
Published: February 2017

Cancer cells have unique but widely varying characteristics that have proven them difficult to be treated by classical therapeutics and calls for novel and selective treatment options. Nanomaterials (NMs) have been shown to display biological effects as a function of their chemical composition, and the extent and exact nature of these effects can vary between different biological environments. Here, ZnO NMs are doped with increasing levels of Fe, which allows to finely tune their dissolution rate resulting in significant differences in their biological behavior on cancer or normal cells. Based on in silico analysis, 2% Fe‐doped ZnO NMs are found to be optimal to cause selective cancer cell death, which is confirmed in both cultured cells and syngeneic tumor models, where they also reduce metastasis formation. These results show that upon tuning NM chemical composition, NMs can be designed as a targeted selective anticancer therapy.
Biomineralization: From Material Tactics to Biological Strategy
Authors: Yao Shasha , Jin Biao , Liu Zhaoming , Shao Changyu , Zhao Ruibo , Wang Xiaoyu , Tang Ruikang
Published: February 2017

Biomineralization is an important tactic by which biological organisms produce hierarchically structured minerals with marvellous functions. Biomineralization studies typically focus on the mediation function of organic matrices on inorganic minerals, which helps scientists to design and synthesize bioinspired functional materials. However, the presence of inorganic minerals may also alter the native behaviours of organic matrices and even biological organisms. This progress report discusses the latest achievements relating to biomineralization mechanisms, the manufacturing of biomimetic materials and relevant applications in biological and biomedical fields. In particular, biomineralized vaccines and algae with improved thermostability and photosynthesis, respectively, demonstrate that biomineralization is a strategy for organism evolution via the rational design of organism‐material complexes. The successful modification of biological systems using materials is based on the regulatory effect of inorganic materials on organic organisms, which is another aspect of biomineralization control. Unlike previous studies, this study integrates materials and biological science to achieve a more comprehensive view of the mechanisms and applications of biomineralization.
Ultrabroadband MoS2 Photodetector with Spectral Response from 445 to 2717 nm
Authors: Xie Ying , Zhang Bo , Wang Shuxian , Wang Dong , Wang Aizhu , Wang Zeyan , Yu Haohai , Zhang Huaijin , Chen Yanxue , Zhao Mingwen , Huang Baibiao , Mei Liangmo , Wang Jiyang
Published: February 2017

Photodetectors with excellent detecting properties over a broad spectral range have advantages for the application in many optoelectronic devices. Introducing imperfections to the atomic lattices in semiconductors is a significant way for tuning the bandgap and achieving broadband response, but the imperfection may renovate their intrinsic properties far from the desire. Here, by controlling the deviation from the perfection of the atomic lattice, ultrabroadband multilayer MoS2 photodetectors are originally designed and realized with the detection range over 2000 nm from 445 nm (blue) to 2717 nm (mid‐infrared). Associated with the narrow but nonzero bandgap and large photoresponsivity, the optimized deviation from the perfection of MoS2 samples is theoretically found and experimentally achieved aiming at the ultrabroadband photoresponse. By the photodetection characterization, the responsivity and detectivity of the present photodetectors are investigated in the wavelength range from 445 to 2717 nm with the maximum values of 50.7 mA W−1 and 1.55 × 109 Jones, respectively, which represent the most broadband MoS2 photodetectors. Based on the easy manipulation, low cost, large scale, and broadband photoresponse, this present detector has significant potential for the applications in optoelectronics and electronics in the future.
Chelation‐Assisted Palladium‐Catalyzed γ‐Arylation of Aliphatic Carboxylic Acid Derivatives
Authors: Dey Aniruddha , Pimparkar Sandeep , Deb Arghya , Guin Srimanta , Maiti Debabrata
Published: February 2017

A palladium(II)‐catalyzed protocol for the highly regioselective remote γ‐C–H arylation of aliphatic carboxylic acid has been disclosed. The 8‐aminoquinoline moiety as an intramolecular bidentate chelator was found to be suitable for this γ‐C–H arylation. Various aryl iodides successfully produced the regioselectively mono‐arylated products with negligible diarylation. Functional group tolerance and easy‐to‐handle reaction conditions make this method attractive.

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Reduced SnO2 Porous Nanowires with a High Density of Grain Boundaries as Catalysts for Efficient Electrochemical CO2‐into‐HCOOH Conversion
Authors: Kumar Bijandra , Atla Veerendra , Brian J. Patrick , Kumari Sudesh , Nguyen Tu Quang , Sunkara Mahendra , Spurgeon Joshua M.
Published: February 2017

Electrochemical conversion of CO2 into energy‐dense liquids, such as formic acid, is desirable as a hydrogen carrier and a chemical feedstock. SnOx is one of the few catalysts that reduce CO2 into formic acid with high selectivity but at high overpotential and low current density. We show that an electrochemically reduced SnO2 porous nanowire catalyst (Sn‐pNWs) with a high density of grain boundaries (GBs) exhibits an energy conversion efficiency of CO2‐into‐HCOOH higher than analogous catalysts. HCOOH formation begins at lower overpotential (350 mV) and reaches a steady Faradaic efficiency of ca. 80 % at only −0.8 V vs. RHE. A comparison with commercial SnO2 nanoparticles confirms that the improved CO2 reduction performance of Sn‐pNWs is due to the density of GBs within the porous structure, which introduce new catalytically active sites. Produced with a scalable plasma synthesis technology, the catalysts have potential for application in the CO2 conversion industry.
Spectroscopic Observation of a Hydrogenated CO Dimer Intermediate During CO Reduction on Cu(100) Electrodes
Authors: Pérez‐Gallent Elena , Figueiredo Marta C. , Calle‐Vallejo Federico , Koper Marc T. M.
Published: February 2017

Carbon dioxide and carbon monoxide can be electrochemically reduced to useful products such as ethylene and ethanol on copper electrocatalysts. The process is yet to be optimized and the exact mechanism and the corresponding reaction intermediates are under debate or unknown. In particular, it has been hypothesized that the C−C bond formation proceeds via CO dimerization and further hydrogenation. Although computational support for this hypothesis exists, direct experimental evidence has been elusive. In this work, we detect a hydrogenated dimer intermediate (OCCOH) using Fourier transform infrared spectroscopy at low overpotentials in LiOH solutions. Density functional theory calculations support our assignment of the observed vibrational bands. The formation of this intermediate is structure sensitive, as it is observed only during CO reduction on Cu(100) and not on Cu(111), in agreement with previous experimental and computational observations.
Asymmetric Total Syntheses of Kopsia Indole Alkaloids
Authors: Leng Lingying , Zhou Xiaohan , Liao Qi , Wang Falu , Song Hao , Zhang Dan , Liu Xiao‐Yu , Qin Yong
Published: February 2017

The asymmetric total syntheses of a group of structurally complex Kopsia alkaloids, (−)‐kopsine, (−)‐isokopsine, (+)‐methyl chanofruticosinate, (−)‐fruticosine, and (−)‐kopsanone, has been achieved. The key strategies for the construction of the molecular complexity in the targets included an asymmetric Tsuji–Trost rearrangement to set the first quaternary carbon center at C20, an intramolecular cyclopropanation by diazo decomposition to install the second and third quaternary carbon centers at C2 and C7, respectively, and a SmI2‐promoted acyloin condensation to assemble the isokopsine core. A radical decarboxylation of an isokopsine‐type intermediate results in a thermodynamic partial rearrangement to give N‐decarbomethoxyisokopsine and N‐decarbomethoxykopsine, two key intermediates for the syntheses of Kopsia alkaloids with different subtype core structures.
Hydroxy‐Directed Ruthenium‐Catalyzed Alkene/Alkyne Coupling: Increased Scope, Stereochemical Implications, and Mechanistic Rationale
Authors: Rummelt Stephan M. , Cheng Gui‐Juan , Gupta Puneet , Thiel Walter , Fürstner Alois
Published: February 2017

The recognition of the dual binding mode of propargyl and allyl alcohols to [Cp*Ru] fragments fostered the development of a highly regioselective intermolecular Alder‐ene‐type reaction of alkynes with 1,2‐disubstituted alkenes. The increased substrate scope opens new perspectives in stereochemical terms. As the loaded catalyst is chiral‐at‐metal, stereochemical information is efficiently relayed from the propargylic site to the emerging C−C bond. This interpretation is based on the X‐ray structure of the first Cp*Ru complex carrying an intact enyne ligand, and provides valuable insights into bonding and activation of the substrates. Computational data draw a clear picture of the principles governing regio‐ and stereocontrol.
Enhanced wide‐range monotonic piezoresistivity, reliability of Ketjenblack/deproteinized natural rubber nanocomposite, and its biomedical application
Authors: Madhanagopal Jagannathan , Singh Om Prakash , Sornambikai Sundaram , Omar Abdul Hafidz , Sathasivam Kathiresan V. , Fatihhi S. J. , Abdul Kadir Mohammed Rafiq
Published: February 2017

Piezoresistive behavior of 6 to 9 wt % Ketjenblack‐reinforced deproteinized natural rubber (KB/DPNR) nanocomposite developed by two‐roll mill was studied under compressive pressure (0 to 12.54 MPa). The 6 wt % KB/DPNR exhibited monotonic piezoresistivity, the highest electrical resistance change (485%), remarkable reversibility and minimal hysteresis. Furthermore, a good sensitivity (S) = 1.1 MPa−1 for 0.25 to 2.49 MPa, high test–retest reliability (intraclass correlation co‐efficient, ICC = 0.99) under 0 to 2.49 MPa for three repetitions conducted at an interval of 24 h and excellent repeatability (standard deviation, SD = 4.8%) to a swing of 6.25 MPa for 50 cyclic compression were achieved. Homogeneous dispersion and high aspect ratio of KB and higher chemical linkage (due to double crosslinking agents) between KB and DPNR may be responsible for the enhanced piezoresistivity. For practical application, the KB/DPNR was interfaced with the microcontroller through a bridge rectifier via custom‐built Simulink and successfully monitored finger pressure in real time during bone movement on human. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44981.
Climbing Bloom's taxonomy pyramid: Lessons from a graduate histology course
Authors: Zaidi Nikki B. , Hwang Charles , Scott Sara , Stallard Stefanie , Purkiss Joel , Hortsch Michael
Published: February 2017

Bloom's taxonomy was adopted to create a subject‐specific scoring tool for histology multiple‐choice questions (MCQs). This Bloom's Taxonomy Histology Tool (BTHT) was used to analyze teacher‐ and student‐generated quiz and examination questions from a graduate level histology course. Multiple‐choice questions using histological images were generally assigned a higher BTHT level than simple text questions. The type of microscopy technique (light or electron microscopy) used for these image‐based questions did not result in any significant differences in their Bloom's taxonomy scores. The BTHT levels for teacher‐generated MCQs correlated positively with higher discrimination indices and inversely with the percent of students answering these questions correctly (difficulty index), suggesting that higher‐level Bloom's taxonomy questions differentiate well between higher‐ and lower‐performing students. When examining BTHT scores for MCQs that were written by students in a Multiple‐Choice Item Development Assignment (MCIDA) there was no significant correlation between these scores and the students' ability to answer teacher‐generated MCQs. This suggests that the ability to answer histology MCQs relies on a different skill set than the aptitude to construct higher‐level Bloom's taxonomy questions. However, students significantly improved their average BTHT scores from the midterm to the final MCIDA task, which indicates that practice, experience and feedback increased their MCQ writing proficiency. Anat Sci Educ 10: 456–464. © 2017 American Association of Anatomists.
Techno‐economic assessment of biogas to liquid fuels conversion technology via Fischer‐Tropsch synthesis
Authors: Okeke Ikenna J. , Mani Sudhagar
Published: February 2017

Biogas derived from anaerobic digestion of organic wastes, and lignocellulosic biomass can be used to produce drop‐in diesel fuel via Fischer‐Tropsch (FT) synthesis. In this study, we developed a process‐based simulation model for the biogas to liquid fuel (BgTL) plant to conduct mass and energy balances and to evaluate techno‐economic assessment of producing drop‐in FT fuels. The BgTL plant operations consisted of biogas cleaning, biomethane reforming, FT synthesis of syngas and hydrocracking and final distillation to produce drop‐in liquid fuels. The unconverted syngas and syncrude were utilized to generate steam and electricity to meet internal plant demand, while the excess power was sold to the grid. The base case BgTL plant (2 000 Nm3/h) produced about 4.6 million gallons per annum of total FT fuels which consisted of 62% diesel, 32% gasoline, 6% LPG with an overall biogas conversion of 54%. A discounted cash flow rate of return (DCFOROR) approach for the Nth plant was used to estimate the capital and operating costs with the minimum selling price for the FT drop‐in fuels of about $5.67/gal ($5.29/GGE). The increase in plant feed capacity to 20 000 Nm3/h decreased the minimum selling price to $2.06/gal ($1.92/GGE). The sensitivity analysis conducted on the base case plant demonstrated that the internal rate of return (IRR), FT conversion rate, plant operating hours, and biogas cost were the most sensitivity parameters to the minimum selling price. Overall, the BgTL technology is deemed to be economically feasible to meet US biofuels demand. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Undergraduate medical academic performance is improved by scientific training
Authors: Zhang Lili , Zhang Wei , Wu Chong , Liu Zhongming , Cai Yunfei , Cao Xingguo , He Yushan , Liu Guoxiang , Miao Hongming
Published: February 2017

The effect of scientific training on course learning in undergraduates is still controversial. In this study, we investigated the academic performance of undergraduate students with and without scientific training. The results show that scientific training improves students’ test scores in general medical courses, such as biochemistry and molecular biology, cell biology, physiology, and even English. We classified scientific training into four levels. We found that literature reading could significantly improve students’ test scores in general courses. Students who received scientific training carried out experiments more effectively and published articles performed better than their untrained counterparts in biochemistry and molecular biology examinations. The questionnaire survey demonstrated that the trained students were more confident of their course learning, and displayed more interest, motivation and capability in course learning. In summary, undergraduate academic performance is improved by scientific training. Our findings shed light on the novel strategies in the management of undergraduate education in the medical school. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(5):379–384, 2017.
Hippocampal AMPARs involve the central sensitization of rats with irritable bowel syndrome
Authors: Chen Aiqin , Chen Yu , Tang Ying , Bao Chengjia , Cui Zizhi , Xiao Meng , Lin Chun
Published: February 2017

Objective

The roles of hippocampal AMPARs were investigated in irritable bowel syndrome (IBS)‐like rats to clarify the central sensitization mechanisms.

Methods

IBS model was induced by neonatal maternal separation. The effects of AMPARs on visceral hypersensitivity were examined by the responses of abdominal muscle to colorectal distension after the bilateral intrahippocampal injections of CNQX (an AMPAR inhibitor). The expressions of hippocampal AMPARs (GluR1 and GluR2) were determined by Western blot.

Results

The IBS‐like rats showed visceral hypersensitivity when compared with controls. Bilateral intrahippocampal injections of CNQX alleviated the visceral pain in IBS‐like rats. The maximal effect appeared at the time point of 30 min, and the duration lasted for 90 min after CNQX application, under 40 and 60 mmHg CRD. The expressions of hippocampal GluR2 significantly increased in IBS‐like rats when compared with controls (p < .05). However, the levels of hippocampal GluR1 had no significant differences in rats. Hippocampal LTP induced by HFS was significantly enhanced when compared with controls (p < .05). The expressions of GluR2 significantly increased in the control and IBS‐like rats after 60 min LTP of recordings (p < .05), but not GluR1.

Conclusion

Neonatal maternal separation enhances the expression of GluR2 and facilitates the LTP in the hippocampus, which could lead to the formation of visceral hypersensitivity when grown up.
Training youth to take drug‐prevention message back home
Authors: Knopf Alison
Published: February 2017

The first major conference for the substance use field since the presidential election took place last month in National Harbor, Maryland, where more than 3,000 community‐based prevention workers and young volunteers gathered for the annual leadership forum of CADCA (Community Anti‐Drug Coalitions of America). Starting with Prevention Day, sponsored by the Substance Abuse and Mental Health Services Administration, the conference had more than 75 workshops on topics ranging from marijuana legislation and tobacco cessation to the opioid epidemic and underage drinking.
Immigrant families across America facing ‘black cloud’ of stress and deportation
Authors: Knopf Alison
Published: February 2017

The American Academy of Pediatrics (AAP) has taken the lead on protecting immigrant children, as the Trump administration issued a series of executive orders shortly after taking office in January that included raids by Immigration and Customs Enforcement (ICE) police from the federal Department of Homeland Security. There were also children denied entry who were refugees, vetted with their families for years and already cleared to enter.
Cobalt‐Catalyzed Regioselective Borylation of Arenes: N‐Heterocyclic Silylene as an Electron Donor in the Metal‐Mediated Activation of C−H Bonds
Authors: Ren Hailong , Zhou Yu‐Peng , Bai Yunping , Cui Chunming , Driess Matthias
Published: February 2017

C−H Borylation of arenes has been a subject of great interest recently because of its atom‐economy and the wide applicability of borylated products in value‐added synthesis. A new bis(silylene)cobalt(II) complex bearing a bis(N‐heterocyclic silylene)‐pyridine pincer ligand (SiNSi) has been synthesized and structurally characterized. It enabled the regioselective catalytic C−H borylation of pyridines, furans, and fluorinated arenes. Notably, it exhibited complementary regioselectivity for the borylation of fluorinated arenes compared to previously known catalytic systems, demonstrating that N‐heterocyclic silylene donors have enormous potential in metal‐catalyzed catalytic applications.
Adiponitrile–Lithium Bis(trimethylsulfonyl)imide Solutions as Alkyl Carbonate‐free Electrolytes for Li4Ti5O12 (LTO)/LiNi1/3Co1/3Mn1/3O2 (NMC) Li‐Ion Batteries
Authors: Farhat Douaa , Ghamouss Fouad , Maibach Julia , Edström Kristina , Lemordant Daniel
Published: February 2017

Recently, dinitriles (NC(CH2)nCN) and especially adiponitrile (ADN, n=4) have attracted attention as safe electrolyte solvents owing to their chemical stability, high boiling points, high flash points, and low vapor pressure. The good solvation properties of ADN toward lithium salts and its high electrochemical stability (≈6 V vs. Li/Li+) make it suitable for safer Li‐ions cells without performance loss. In this study, ADN is used as a single electrolyte solvent with lithium bis(trimethylsulfonyl)imide (LiTFSI). This electrolyte allows the use of aluminium collectors as almost no corrosion occurs at voltages up to 4.2 V. The physicochemical properties of the ADN–LiTFSI electrolyte, such as salt dissolution, conductivity, and viscosity, were determined. The cycling performances of batteries using Li4Ti5O12 (LTO) as the anode and LiNi1/3Co1/3Mn1/3O2 (NMC) as the cathode were determined. The results indicate that LTO/NMC batteries exhibit excellent rate capabilities with a columbic efficiency close to 100 %. As an example, cells were able to reach a capacity of 165 mAh g−1 at 0.1 C and a capacity retention of more than 98 % after 200 cycles at 0.5 C. In addition, electrodes analyses by SEM, X‐ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy after cycling confirming minimal surface changes of the electrodes in the studied battery system.
Photoredox‐Catalyzed Isatin Reactions: Access to Dibenzo‐1,7‐Naphthyridine Carboxylate and Tryptanthrin
Authors: Sultan Shaista , Gupta Vivek , Shah Bhahwal Ali
Published: February 2017

A procedure for the synthesis of dibenzo‐1,7‐naphthyridine carboxylate by means of photoredox catalysis has been developed. The reaction features an umpolung reaction of the keto group at the C‐3 position and entrapment of the decarbonylation‐prone C‐2 position of isatin. Additionally, the method is employed to showcase the chemodivergent behavior of isatins in aprotic solvents leading to the synthesis of tryptanthrin derivatives through photoredox catalysis. The reaction is demonstrated to be scalable (up to gram scale) and straightforward in terms of set up.
Low leopard populations in protected areas of Maputaland: a consequence of poaching, habitat condition, abundance of prey, and a top predator
Authors: Ramesh Tharmalingam , Kalle Riddhika , Rosenlund Havard , Downs Colleen T.
Published: February 2017

Identifying the primary causes affecting population densities and distribution of flagship species are necessary in developing sustainable management strategies for large carnivore conservation. We modeled drivers of spatial density of the common leopard (Panthera pardus) using a spatially explicit capture–recapture—Bayesian approach to understand their population dynamics in the Maputaland Conservation Unit, South Africa. We camera‐trapped leopards in four protected areas (PAs) of varying sizes and disturbance levels covering 198 camera stations. Ours is the first study to explore the effects of poaching level, abundance of prey species (small, medium, and large), competitors (lion Panthera leo and spotted hyenas Crocuta crocuta), and habitat on the spatial distribution of common leopard density. Twenty‐six male and 41 female leopards were individually identified and estimated leopard density ranged from 1.6 ± 0.62/100 km2 (smallest PA—Ndumo) to 8.4 ± 1.03/100 km2 (largest PA—western shores). Although dry forest thickets and plantation habitats largely represented the western shores, the plantation areas had extremely low leopard density compared to native forest. We found that leopard density increased in areas when low poaching levels/no poaching was recorded in dry forest thickets and with high abundance of medium‐sized prey, but decreased with increasing abundance of lion. Because local leopard populations are vulnerable to extinction, particularly in smaller PAs, the long‐term sustainability of leopard populations depend on developing appropriate management strategies that consider a combination of multiple factors to maintain their optimal habitats.
Chemical and nutritive characteristics of tree nut oils available in the U.S. market
Authors: Gong Yi , Pegg Ronald B. , Carr Elizabeth C. , Parrish Daniel R. , Kellett Mary E. , Kerrihard Adrian L.
Published: February 2017

Tree nuts have become increasingly popular in the U.S. market due to their healthful fats and beneficial micronutrients and bioactives. The use of specialty tree nut oils has also been growing in popularity. As proper quality control measures are not currently in place, and published information on tree nut oils in the USDA National Nutrient Database for Standard Reference (SR28) is antiquated, an improved understanding of nut oil compositions could be of use to the industry and field. In this study, 20 commercially available brands of specialty tree nut oils, either imported or domestic, were analyzed to determine their contents of fatty acids, tocopherols (Ts), and phytosterols. While recent publications and the USDA Database confirm that γ‐T is the primary homolog endogenous to pecan oil, three of the four pecan oil samples tested were found to be most concentrated in α‐T. The T concentrations were also determined to be highly predictive of nut oil unsaturation (as summarized by calculated iodine values;  = 0.913), with the concentration of δ‐T presenting the greatest numeric weight to the model. The compositional information presented in this paper provides more in‐depth information on commercially available specialty tree nut oils.

Practical applications: The information reported provides a better understanding of important compositional factors within tree nut oils, which can be of benefit to those that either produce or utilize such oils. These understandings are important to nutritional considerations, and may also inform the optimizations of processing and storage techniques. This study also contributes to our understanding of the relationship between endogenous T concentrations and oil unsaturation, which may improve our knowledge of antioxidative properties of Ts.

Consumers are using tree nut oils in food preparations more frequently these days, partially due to the health benefits associated with these specialty oils. Limited research exists in nutritional databases about the lipid constituents – namely the fatty acids, phytosterols, and vitamin E contents – of these oils. This paper reports on the characterization of these constituents in raw and roasted tree nut oils available commercially.
Direct and Regioselective Introduction of Acetals into Imidazoles at the 2‐Position by an Iridium‐Catalyzed Reaction with Formates in the Presence of Hydrosilanes
Authors: Fukumoto Yoshiya , Iyori Yasuaki , Chatani Naoto
Published: February 2017

The iridium‐catalyzed reaction of imidazoles with formates in the presence of hydrosilanes as coreactants led to the production of 2‐[(alkoxy)(siloxy)methyl]imidazoles. Dimethyl acetylenedicarboxylate was the additive of choice for the reaction in terms of reaction efficiency. No reaction was observed in the absence of the hydrosilanes. Whereas substituents at the 1‐ and 5‐positions on the imidazole ring did not affect the reaction, substituents at the 4‐position greatly retarded the reaction. The regioselective reaction of 1‐methyl‐1,2,4‐triazole occurred at the carbon atom between the sp3 and sp2 nitrogen atoms of the ring but not between two sp2 nitrogen atoms. The products were converted into imidazole 2‐carbaldehydes by hydrolysis under acidic conditions.
(±)‐Peharmaline A: A Pair of Rare β‐Carboline–Vasicinone Hybrid Alkaloid Enantiomers from Peganum harmala
Authors: Wang Kai‐Bo , Li Sheng‐Ge , Huang Xue‐Yan , Li Da‐Hong , Li Zhan‐Lin , Hua Hui‐Ming
Published: February 2017

(±)‐Peharmaline A (1), a pair of rare β‐carboline–vasicinone hybrid alkaloid enantiomers with the hitherto unknown hybrid dimeric system, was isolated from the seeds of Peganum harmala L. Their structures, including absolute configurations, were determined by extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Plausible biogenetic pathways involving Mannich/Pictet–Spengler‐type and intermolecular Michael addition reactions are briefly discussed. Compound 1 exhibited significant cytotoxic activities against HL‐60, PC‐3, and SGC‐7901 cancer cell lines with median inhibitory concentration values of 9.2, 21.6, and 25.4 µm, respectively. However, two biosynthetically related precursors, harmaline and vasicinone, were inactive. This cytotoxic β‐carboline–vasicinone hybrid dimeric alkaloid may give some insight into the discovery of new lead compounds for cancer therapy.