bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and Validation of Eco-Friendly Liquid Chromatographic and Spectrophotometric Methods for Simultaneous Determination of Coformulated Drugs: Phenylephrine Hydrochloride and Prednisolone Acetate
Authors: Mostafa Nadia M , Elsayed Ghada M , Hassan Nagiba Y , El Mously Dina A 
Published: July 2017

Abstract
Five simple, sensitive, and eco-friendly LC and UV spectrophotometric methods have been developed for the simultaneous determination of phenylephrine hydrochloride (PHE) and prednisolone acetate (PRD) in their combined dosage form. The first method was reversed-phase (RP) LC using methanol–water–heptane-1-sulfonic acid sodium salt (75 + 25 + 0.1, v/v/w) as a mobile phase. Separation was achieved using an XSelect HSS reversed-phase C18 analytical column (250 × 4.6 mm, 5µm). The flow rate was 1.0 mL/min and UV detection was done at 230 nm. Quantification was achieved over the concentration ranges of 5–50 µg/mL for PHE and 2–90 µg/mL for PRD. Four spectrophotometric methods were proposed, namely dual wavelength, first derivative of ratio spectra, ratio difference, and mean-centering of ratio spectra. Linearity was observed in the concentration ranges of 10–120 and 5–35 µg/mL for PHE and PRD, respectively, for the spectrophotometric methods. Green solvents were used in the proposed methods because they play a vital role in the analytical methods’ influence on the environment. The suggested methods were validated regarding linearity, accuracy, and precision according to the International Conference on Harmonization guidelines, with satisfactory results. These methods could be used as harmless substitutes for routine analysis of the mentioned drugs, with no interference from excipients.
Les pêches maritimes : un terrain d’expérimentation de la géoprospective
Authors: Tissière Laurie , Mahévas Stéphanie , Michel Charlotte , Trouillet Brice 
Published: July 2017

La prospective construit des scénarios d’évolution – pour la planification ou pour la protection de l’environnement – dans le but de susciter la discussion et la mise en perspective des visions d’avenir. Cette démarche orientée vers le futur rencontre un tournant spatial avec l’émergence de la géoprospective qui, en spatialisant les conjectures, permet de mettre en évidence des dynamiques géographiques et d’intégrer les enjeux spatiaux dans le débat. Une application participative de géoprospective aux pêches maritimes présente un double intérêt. Le premier est scientifique : il s’agit de contribuer aux corpus méthodologique et épistémologique de la géoprospective. En effet, la proposition de méthode permet de discuter la fonction des modèles, d’une part, et le rôle des chercheurs et des acteurs, d’autre part. Le second intérêt d’une géoprospective des pêches maritimes est opérationnel : l’amélioration de la connaissance collective sur les dynamiques et les enjeux sociospatiaux des pêches est de nature à faciliter le dialogue entre parties prenantes. À terme, ce dialogue peut être prolongé sous la forme d’une stratégie de gestion coconstruite.
La evolución del género ‘Homo’: Nuevas incógnitas y perspectivas
Authors: Agustí Jordí 
Published: July 2017

En este trabajo se pasa revista a las principales cuestiones que afectan a la evolución del género Homo, como es el caso de su origen, el problema de la variabilidad en Homo erectus y el impacto de la paleogenómica. Todavía no se ha llegado a un consenso sobre el candidato australopitecino que dio lugar a los primeros representantes asignables a Homo. Esta discusión afecta incluso al propio reconocimiento de las especies H. habilis y H. rudolfensis. Por lo que respecta a la cuestión de la variabilidad de los primeros paleodemes asignados a Homo, los hallazgos realizados en el yacimiento georgiano de Dmanisi han puesto en cuestión algunos de los criterios utilizados hasta ahora para distinguir entre especies como H. erectus o H. ergaster. Finalmente, la irrupción de la paleogenómica ha puesto en evidencia que el flujo genético entre antiguas poblaciones de homininos fue mayor de lo esperado.
Preparation of axial-type wire-structure crystalline silicon solar cells
Authors: Shirayanagi Yusuke , Yashiki Yasutoshi , Kato Shinya , Konagai Makoto 
Published: July 2017

Abstract
The fabrication of an axial-type microwire-structure silicon (Si-MW) solar cell has been studied, and it is compared with the radial-type Si-MW solar cell. In this study, a number of microwires were formed on a p-type Si wafer and an n-layer were fabricated on the top region of microwires to form p–n junctions. After that, Si-MWs were filled with an Al1−

x
O
x
film, deposited by thermal atomic layer deposition, and silica particles, respectively. Then, the Al1−

x
O
x
film and silica particles on the n-layer were removed by chemical mechanical polishing to form an electrical contact with the electrode. As a result, we obtained a conversion efficiency of 8.2% from the axial-type Si-MW solar cell. In addition, compared with a radial-type Si-MW solar cell, a higher quantum efficiency was obtained in the short-wavelength region (300–600 nm) for the axial-type Si-MW solar cell.
Dehydration‐induced instabilities at intermediate depths in subduction zones
Authors: Brantut Nicolas , Stefanou Ioannis , Sulem Jean 
Published: July 2017

AbstractWe formulate a model for coupled deformation and dehydration of antigorite, based on a porosity‐dependent yield criterion and including shear‐enhanced compaction. A pore pressure and compaction instability can develop when the net volume change associated with the reaction is negative, i.e., at intermediate depth in subduction zones. The instability criterion is derived in terms of the dependence of the yield criterion on porosity: if that dependence is strong, instabilities are more likely to occur. We also find that the instability is associated with strain localization, over characteristic length scales determined by the hydraulic diffusivity, the elasto‐plastic parameters of the rock, and the reaction rate. Typical lower bounds for the localization length are of the order of 10 to 100 for antigorite dehydration and deformation at 3 GPa. The fluid pressure and deformation instability is expected to induce stress buildup in the surrounding rocks forming the subducted slab, which provides a mechanism for the nucleation and propagation of intermediate‐depth earthquakes.
Changes in water properties and flow regime on the continental shelf off the Adélie/George VLand coast, East Antarctica, after glacier tongue calving
Authors: Aoki S. , Kobayashi R. , Rintoul S. R. , Tamura T. , Kusahara K. 
Published: July 2017

AbstractOceanic changes before and after the relocation of iceberg B9B and calving of the Mertz Glacier Tongue (MGT) in February 2010 are examined on the continental shelf off the Adélie Land/George V Land coast, East Antarctica. Summer hydrographic observations, including stable oxygen isotope ratio (δ18O), in 2001/2008 and 2011/2015 and results of a numerical model are used. Along the western flank of the MGT, temperature decreased between 2001 and 2015 for most of the water column in the Adélie Depression. δ18O generally decreased, especially at the MGT draft depths on the northern side. West of the MGT, temperature, salinity, and δ18O decreased in the intermediate layer. East of the MGT, in contrast, temperature increased between 2001 and 2011 at intermediate depths, salinity increased in the intermediate and deep layers, and δ18O slightly decreased in the deep layer but did not change much around 300 dbar. The numerical experiment exhibits a change in ocean circulation, revealing an increase in modified Circumpolar Deep Water (mCDW) inflow in the east and a decrease in the west. The contrasting changes in mCDW intrusion are consistent between the observations and numerical model, and are indicative of the effect of removal of the ice barriers. The contrast is overlain by overall decreases in salinity and δ18O, which suggests an increase in the continental meltwater fraction of 5–20% and might reveal a wide‐ranging influence from West Antarctica. The oxygen isotope ratio is, hence, effective in monitoring the increase in continental melt over the Antarctic shelf.
Does vapor pressure deficit drive the seasonality of δ13C of the net land‐atmosphere CO2exchange across the United States?
Authors: Raczka B. , Biraud S. C. , Ehleringer J. R. , Lai C.‐T. , Miller J. B. , Pataki D. E. , Saleska S. R. , Torn M. S. , Vaughn B. H. , Wehr R. , Bowling D. R. 
Published: July 2017

AbstractThe seasonal pattern of the carbon isotope content (δ13C) of atmospheric CO2depends on local and nonlocal land‐atmosphere exchange and atmospheric transport. Previous studies suggested that the δ13C of the net land‐atmosphere CO2flux (δsource) varies seasonally as stomatal conductance of plants responds to vapor pressure deficit of air (VPD). We studied the variation ofδsourceat seven sites across the United States representing forests, grasslands, and an urban center. Using a two‐part mixing model, we calculated the seasonalδsourcefor each site after removing background influence and, when possible, removing δ13C variation of nonlocal sources. Compared to previous analyses, we found a reduced seasonal (March–September) variation inδsourceat the forest sites (0.5‰ variation). We did not find a consistent seasonal relationship between VPD andδsourceacross forest (or other) sites, providing evidence that stomatal response to VPD was not the cause of the global, coherent seasonal pattern inδsource. In contrast to the forest sites, grassland and urban sites had a larger seasonal variation inδsource(5‰) dominated by seasonal transitions in C3/C4grass productivity and in fossil fuel emissions, respectively. Our findings were sensitive to the location used to account for atmospheric background variation within the mixing model method that determinedδsource.Special consideration should be given to background location depending on whether the intent is to understand site level dynamics or regional scale impacts of land‐atmosphere exchange. The seasonal amplitude in δ13C of land‐atmosphere CO2exchange (δsource)varied across land cover types and was not driven by seasonal changes in vapor pressure deficit. The largest seasonal amplitudes ofδsourcewere at grassland and urban sites, driven by changes in C3/C4grass productivity and fossil fuel emissions, respectively. Mixing model approaches may incorrectly calculateδsourcewhen background atmospheric observations are remote and/or prone to anthropogenic influence.
t‐Darpp is an elongated monomer that binds calcium and is phosphorylated by cyclin‐dependent kinases 1 and 5
Authors: Momand Jamil , Magdziarz Patrycja , Feng You , Jiang Dianlu , Parga Elizabeth , Celis Arianna , Denny Erin , Wang Xiaoying , Phillips Martin L. , Monterroso Estuardo , Kane Susan E. , Zhou Feimeng 
Published: July 2017

t‐Darpp (truncated isoform of dopamine‐ and cAMP‐regulated phosphoprotein) is a protein encoded by the PPP1R1B gene and is expressed in breast, colon, esophageal, gastric, and prostate cancers, as well as in normal adult brain striatal cells. Overexpression of t‐Darpp in cultured cells leads to increased protein kinase A activity and increased phosphorylation of AKT (protein kinase B). In HER2+ breast cancer cells, t‐Darpp confers resistance to the chemotherapeutic agent trastuzumab. To shed light on t‐Darpp function, we studied its secondary structure, oligomerization status, metal‐binding properties, and phosphorylation by cyclin‐dependent kinases 1 and 5. t‐Darpp exhibits 12% alpha helix, 29% beta strand, 24% beta turn, and 35% random coil structures. It binds calcium, but not other metals commonly found in biological systems. The T39 site, critical for t‐Darpp activation of the AKT signaling pathway, is a substrate for phosphorylation by cyclin‐dependent kinase 1 and cyclin‐dependent kinase 5. Gel filtration chromatography, sedimentation equilibrium analysis, blue native gel electrophoresis, and glutaraldehyde‐mediated cross‐linking experiments demonstrate that the majority of t‐Darpp exists as a monomer, but forms low levels (< 3%) of hetero‐oligomers with its longer isoform Darpp‐32. t‐Darpp has a large Stokes radius of 4.4 nm relative to its mass of 19 kDa, indicating that it has an elongated structure.
Tunable Dimerization and Trimerization of β‐Alkynyl Ketones via Silver Catalysis for Accessing Spiro and Dispiro Compounds Containing 1H‐Isochromene
Authors: Wang Dan , Liu Shuai , Lan Xin‐Chan , Paniagua Armando , Hao Wen‐Juan , Li Guigen , Tu Shu‐Jiang , Jiang Bo 
Published: July 2017

AbstractNew silver‐catalyzed tunable dimerization and trimerization reactions of β‐alkynyl ketones have been established, enabling multiple C−C bond‐forming events to selectively access skeletally diverse spiroisochromenes with generally good yields. The silver‐enabled bicycloaddition of β‐alkynyl ketones with water offered hydroxylated spiroisochromenes. Without water, spiroisochromenes with a methylene moiety were obtained through catalytic 6‐endo‐dig oxo‐cyclization/[4+2] cycloaddition cascades by using pyridine as additive whereas employment of 1,1′‐binaphthyl‐2,2′‐diyl hydrogen phosphate (BiNPO4H) as a Brønsted acid catalyst rendered the unprecedented dispiro trimerization products through double C(sp3)–H functionalization.magnified image
Ruthenium‐Catalyzed Oxidative Formal Aza‐Diels–Alder Reaction: Enantioselective Synthesis of Benzo[a]quinolizine‐2‐ones
Authors: Yao Yuan , Zhu Hai‐Jie , Li Fang , Zhu Cheng‐Feng , Luo Yun‐Fei , Wu Xiang , Kantchev Eric Assen B. 
Published: July 2017

AbstractA method for the preparation of thermodynamic (4R,11bS)‐benzo[a]quinolizine‐2‐one derivatives in good enantio‐ and diastereoselectivity by a one‐pot oxidative formal aza‐Diels–Alder reaction of 1,2,3,4‐tetrahydroisoquinolines and α,β‐unsaturated ketones is described. The reaction proceeds via tandem ruthenium‐catalyzed amine dehydrogenation using tert‐butyl hydroperoxide (TBHP) as the oxidant and a chiral thiourea‐catalyzed formal aza‐[4+2] cycloaddition, providing a step‐economical strategy for the synthesis of these valuable heterocyclic products.magnified image
Biomimetische Synthese komplexer Flavonoide isoliert aus Daemonorops‐“Drachenblut”
Authors: Schmid Matthias , Trauner Dirk 
Published: July 2017

AbstractDragonbloodin A1 und A2 sind ein Paar komplexer Flavonoidtrimere, die aus der Palmenart Daemonorops draco isoliert wurden. Wir präsentieren hier eine kurze Synthese, die ihre relative Konfiguration sowie ihren natürlichen Ursprung aufklärt. Die Synthese zeichnet sich durch biomimetische Reaktionskaskaden aus, an denen sowohl ionische als auch radikalische Intermediate beteiligt sind. Außerdem wird die Beziehung zwischen Dracorhodin, den Dracoflavanen C sowie den Dragonbloodinen A1 und A2 behandelt.
Druckeffekte auf organische Reaktionen in Fluiden – eine neue theoretische Perspektive
Authors: Chen Bo , Hoffmann Roald , Cammi Roberto 
Published: July 2017

AbstractDieser Aufsatz zeigt eine neue Perspektive für die Untersuchung chemischer Reaktionen in komprimierten flüssigen Medien auf. Wir beginnen, indem wir die wesentlichen Einsichten zusammenfassen, die in über 50 Jahren experimenteller Studien an organischen Reaktionen in Lösung unter Druck gewonnen wurden. Diese Arbeiten führten zu einer zuverlässigen Beurteilung der kritischen Rolle der Aktivierungs‐ (Δ≠V) und Reaktionsvolumen (ΔV) beim Verständnis von Druckeffekten auf Geschwindigkeiten und Gleichgewichte organischer Reaktionen. Eine kürzlich entwickelte Computermethode, die XP‐PCM‐Methode (XP‐PCM=extreme pressure polarizable continuum model), die quantenchemische Berechnungen von Reaktionswegen von Molekülen unter Druck vornehmen kann, wird eingeführt. Eine Fallstudie der Diels‐Alder‐Cycloaddition von Cyclopentadien mit Ethylen soll – in pädagogischem Detail – der Beschreibung der Methode dienen. Anschließend wenden wir die XP‐PCM‐Methode auf eine Auswahl anderer pericyclischer Reaktionen an, einschließlich der Diels‐Alder‐Cycloaddition von Butadien mit Ethylen, der elektrocyclischen Ringöffnung von Cyclobuten, dem elektrocyclischen Ringschluss von Z‐Hexatrien, der [1,5]‐H‐Verschiebung in Z‐Pentadien und der Cope‐Umlagerung. Diese Reaktionen dienen als Beispiele für einige der häufigsten Kombinationen von Δ≠V und ΔV. Interessante Phänomene, wie die Verschiebung eines Übergangszustands entlang der Reaktionskoordinate, ein Wechsel des geschwindigkeitsbestimmenden Schrittes und die mögliche Umwandlung eines Übergangszustands in ein stabiles Minimum, werden durch diese Berechnungen aufgedeckt. Ein Profil des Reaktionsvolumens, entsprechend der Änderung des Volumens des reagierenden Moleküls im Verlauf der Reaktion, erweist sich als nützlich.
Oxygenation of Simple Olefins through Selective Allylic C−C Bond Cleavage: A Direct Approach to Cinnamyl Aldehydes
Authors: Liu Jianzhong , Wen Xiaojin , Qin Chong , Li Xinyao , Luo Xiao , Sun Ao , Zhu Bencong , Song Song , Jiao Ning 
Published: July 2017

AbstractA novel metal‐free allylic C−C σ‐bond cleavage of simple olefins to give valuable cinnamyl aldehydes is reported. 1,2‐Aryl or alkyl migration through allylic C−C bond cleavage occurs in this transformation, which is assisted by an alkyl azide reagent. This method enables O‐atom incorporation into simple unfunctionalized olefins to construct cinnamyl aldehydes. The reaction features simple hydrocarbon substrates, metal‐free conditions, and high regio‐ and stereoselectivity.
Highly Selective and Efficient Ring Hydroxylation of Alkylbenzenes with Hydrogen Peroxide and an Osmium(VI) Nitrido Catalyst
Authors: Kwong Hoi‐Ki , Lo Po‐Kam , Yiu Shek‐Man , Hirao Hajime , Lau Kai‐Chung , Lau Tai‐Chu 
Published: July 2017

AbstractThe OsVI nitrido complex, OsVI(N)(quin)2(OTs) (1, quin=2‐quinaldinate, OTs=tosylate), is a highly selective and efficient catalyst for the ring hydroxylation of alkylbenzenes with H2O2 at room temperature. Oxidation of various alkylbenzenes occurs with ring/chain oxidation ratios ranging from 96.7/3.3 to 99.9/0.1, and total product yields from 93 % to 98 %. Moreover, turnover numbers up to 6360, 5670, and 3880 can be achieved for the oxidation of p‐xylene, ethylbenzene, and mesitylene, respectively. Density functional theory calculations suggest that the active intermediate is an OsVIII nitrido oxo species.
Ecofriendly modification of acetosolv lignin from oil palm biomass for improvement of PMMA thermo‐oxidative properties
Authors: de Oliveira Davi Rabelo , Nogueira Izabel de Menezes , Maia Francisco Jonas Nogueira , Rosa Morsyleide Freitas , Mazzetto Selma Elaine , Lomonaco Diego 
Published: July 2017

ABSTRACTThe environmentally friendly esterification of acetosolv lignin (AL), obtained from pressed oil palm mesocarp fibers, is described, for the improvement of thermo‐oxidative properties of poly(methyl methacrylate) (PMMA) films. Acetylation of AL was performed in ecofriendly conditions using acetic anhydride in the absence of catalysts. Acetylated acetosolv lignin (AAL) was successfully obtained in only 12 min with a solvent‐free and catalyst‐free microwave‐assisted procedure. Lignins were characterized by Fourier transform infrared spectroscopy, size exclusion chromatography, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC), confirming the efficacy of the methodology employed. AL and AAL as fillers in different concentrations (1% and 5%) were added to PMMA films. The thermal and mechanical properties of the lignin‐incorporated films were analyzed by TGA, DSC, and dynamic mechanical analysis (DMA). The films incorporated with lignin and acetylated lignin presented initial degradation temperature (Tonset) and onset oxidative temperature (OOT) values higher than pure PMMA films, contributing thus to an enhancement of thermo‐oxidative stability of PMMA. The DMA analyses showed that incorporation of AL or AAL increased the storage modulus (E′) of PMMA films, but did not affect their glass‐transition temperatures (Tg). The results indicate the potential use of oil palm mesocarp lignin to enhance the thermo‐oxidative properties of PMMA without compromising its mechanical response. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45498.
Evaluation of CO2 adsorption capacity of electrospun carbon fibers with thermal and chemical activation
Authors: Kim Dong Woo , Jung Dong Won , Adelodun Adedeji A. , Jo Young Min 
Published: July 2017

ABSTRACTThe use of urea was investigated as an alternative to the poisonous and expensive NH3 gas, commonly used for amination of adsorbents. First, we fabricated activated carbon nanofibers (AnFs) by electrospinning of urea‐doped polyacrylonitrile solution (N‐AnF). By increasing the activation temperature, the average specific surface area (SBET) and micropore volume (Vmicro) of pristine nFs improved from 27.3 to 300 m2/g and 0.004 to 0.13 cm3/g, respectively. Upon urea doping, both properties were further enhanced to 542 m2/g and 0.22 cm3/g, respectively. However, with chemical investigation via X‐ray photoelectron spectroscopy, we observed that the urea‐doping incorporated more of less desired quaternary‐N, along with other more basic and desirable N‐functionalities (i.e., nitrile, pyridinic, pyrrolic N) tethered. Based on the eventual CO2 adsorption results, we realized that average pore diameter (davg) is a limiting factor with regard to CO2 adsorption by AnFs; the lower the davg, the better the adsorption. Further examination via adsorption isotherm model fitting showed that CO2 molecules were homogenously collected in a monolayer pattern. However, three‐parameter model Redlich–Peterson model best fits the experimental data, suggesting that the adsorption is concentration‐driven and that it tends toward Langmuir rather than Freundlich at elevated concentration of CO2. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45534.
A review on comparative mechanistic studies of antimicrobial peptides against archaea
Authors: Varnava Kyriakos G. , Ronimus Ron S. , Sarojini Vijayalekshmi 
Published: July 2017

AbstractArchaea was until recently considered as a third domain of life in addition to bacteria and eukarya but recent studies support the existence of only two superphyla (bacteria and archaea). The fundamental differences between archaeal, bacterial, and eukaryal cells are probably the main reasons for the comparatively lower susceptibility of archaeal strains to current antimicrobial agents. The possible emerging pathogenicity of archaea and the role of archaeal methanogens in methane emissions, a potent greenhouse gas, has led many researchers to examine the sensitivity patterns of archaea and make attempts to find agents that have significant anti‐archaeal activity. Even though antimicrobial peptides (AMPs) are well known with several published reviews concerning their mode of action against bacteria and eukarya, to our knowledge, to date no reviews are available that focus on the action of these peptides against archaea. Herein, we present a review on all the peptides that have been tested against archaea. In addition, in an attempt to shed more light on possible future work that needs to be performed we have included a brief overview of the chemical characteristics, spectrum of activity, and the known mechanism of action of each of these peptides against bacteria and/or fungi. We also discuss the nature of and key physiological differences between Archaea, Bacteria, and Eukarya that are relevant to the development of anti‐archaeal peptides. Despite our relatively limited knowledge about archaea, available data suggest that AMPs have an even broader spectrum of activity than currently recognized.