bluuebunny/crossref_metadata_2025 huggingface dataset:
Análisis del Uso del Bioetanol como Medida de Mitigación y su Impacto en el Sector Hídrico: Estudio en una Región Cañera en México
Authors: Navarro Inés Josefina Gonzalez , Jiménez Blanca Elena , Haro María Eugenia , Aponte Nidya
Published: July 2014

O uso de biocombustíveis nos transportes é uma medida de mitigação para reduzir as emissões de gases do efeito estufa; entretanto, pode ter efeitos ambientais negativos. Esta pesquisa analisa os impactos atual e futuro da produção de etanol a partir da cana-de-açúcar nos recursos hídricos do México. Estimou-se a pegada hídrica, a disponibilidade e a demanda de água em uma região canavieira do país com base no balanço hídrico e nas condições climáticas locais. Os resultados mostraram que a pegada de água histórica (1980-2007) da cana-de-açúcar foi de 104,9 m3/t, considerando o uso de irrigação por sulco. No entanto, na região estudada são utilizados três sistemas de irrigação (por sulco, aspersão e gotejamento), razão pela qual a pegada de água varia entre 58,7 e 73,4 m3/t, o que indica uma economia de 20% (33 mm3) de água. A disponibilidade de água na região foi estimada em 255 Mm3/ano, com um índice de estresse de 60%, indicando um elevado grau de pressão sobre os recursos hídricos. Para cenários futuros de mudança climática, estimou-se um aumento de 3% na pegada de água; no entanto, o balanço hídrico mostrou que este aumento relativamente pequeno terá um impacto significativo na demanda de água. O México tem uma disponibilidade 18 vezes menor do que a do Brasil e quase sete vezes menor do que a dos EUA, de modo que a alternativa de produzir etanol requer o estudo de cada uma das regiões canavieiras para avaliar suas vantagens e desvantagens.
Eletricidade para o bombeamento de água subterrânea: limitações e oportunidades para respostas adaptativas às mudanças climáticas
Authors: Scott Christopher A.
Published: July 2014

Globalmente, o uso de água subterrânea tem se intensificado para suprir as demandas de irrigação, abastecimento urbano, industrialização e, em alguns casos, geração de energia elétrica. Em resposta à variabilidade hidroclimática, a água superficial vem sendo substituída por água subterrânea, o que deve ser visto como um recurso estratégico para a adaptação climática. Nesse sentido, o abastecimento de eletricidade para o bombeamento de água seria uma ferramenta política de adaptação. O presente trabalho examina a influência do abastecimento e dos preços da eletricidade sobre a irrigação com água subterrânea e as emissões resultantes, referindo-se mais especificamente ao caso do México – uma “tempestade perfeita” na relação entre clima, água e energia. O abastecimento de energia no período da noite, com tarifas abaixo das taxas já subsidiadas para o uso agrícola de água subterrânea, levou os produtores mexicanos a intensificarem o bombeamento, revertendo os efeitos de avanços importantes no condizente à conservação de água e eletricidade. O bombeamento indiscriminado de água subterrânea, incluindo exportação de água virtual na produção agrícola, ameaça a sustentabilidade dos aquíferos a longo prazo, bem como dos usos não agrícolas da água e das interações entre rios e aquíferos que mantêm os ecossistemas ribeirinhos. Estima-se que as emissões resultantes da extração de água subterrânea para uso agrícola no México represente 3,6% das emissões nacionais totais e sejam equivalentes às emissões para o transporte dessa mesma produção agrícola ao mercado. O artigo conclui com uma avaliação das tendências em energia, água e clima, combinadas com políticas futuras para tratar desses desafios.
Social criticism in late Byzantium voiced under the veil of biblical teachings: The example of Alexios Makrembolites
Authors: Gašić Dejan
Published: July 2014

The paper strives to highlight the interpretation of text 'A Dialogue Between the Rich and the Poor' written by Alexios Makrembolites, and hence the contribution of source texts to the understanding of Byzantine reality and literature in the fourteenth century. Although he is vaguely defined by his life epopee, his modest biography and inspiring words enabled Makrembolites to point out that the hardships of late Byzantium - civil war and social injustice - had been inflicted upon him, with the corollary of his own literary consciousness being shaped by the noxious effects of these predicaments. Even though the 14th-century Byzantine literature abounds in social themes, the distinctiveness of a Dialogue Between the Rich and the Poor is to be found in its bitter tone against social inequality and biased sympathy for the poorer fellow citizens to whom the author himself belonged. The dynamic historical course and segregation of Romaioi were viewed, in his case, through the lens of wise teachings derived from the Bible, wherewith the latent criticism of the state system became veiled in votive messages. Given the period and conditions under which he wrote, such a 'historical drama' can only be understood as a historiosophical interpretation of events. As such, it could only stem from the Holy Scripture. In this way Makrembolites emphasises a handful of didactic biblical moments and 'canons of conduct' the rich should adhere to, so that the kingdom could survive on the foundations of charity and philanthropy.
Proactive Measures Stem Tide of Water Loss
Authors: Hanley Kipp
Published: July 2014

The Prince William County (Va.) Service Authority continually strives to optimize revenue, reduce costs, and improve environmental stewardship. Minimizing water loss is an important part of that effort.
What is A Network? (And Who is Andrew Lang?)
Authors: Hensley Nathan K.
Published: July 2014

This essay traces the strikingly prolific career of Andrew Lang and places that career in the context of the shifting late-Victorian literary field, which Lang served importantly to shape. The essay introduces Lang’s milieu and re-orients readers to a literary personality who, while known, is only rarely studied in his own right—a detail of reception history the essay explains with recourse to the relational sociology of Pierre Bourdieu and Bruno Latour. Restoring Lang’s “network effect” through historical analysis helps raise a number of conceptual questions, each of which is pursued in the essays of this special issue: such questions include the nature of textual interpretation, the changing outlines of disciplines, the philosophy of historical method, and conceptions of authorship and collaboration in the modern cultural marketplace. Placing Lang back in his proper spot at the center of the late-Victorian networks he helped convene (1) helps historicize our understanding of the modern “field of cultural production” (Bourdieu’s term) in an expanded, protodisciplinary sense and (2) discloses new genealogies of literary and theoretical history. These new genealogies in turn cast altered light on the methodological presuppositions we draw upon to evaluate Lang and his network here. “Theoretical historicism” is the term used to describe approaches that trace such feedback loops between the historical object analyzed and the modern method used to analyze them.
“Romantic Realism/Victorian Romance”: An Introduction to Four Provocations
Authors: Freedgood Elaine , McLane Maureen N.
Published: July 2014

Might we, Romanticists and Victorianists, be or become one people? This cluster of essays, by Ian Duncan, Mary Favret, Catherine Robson, and Herbert Tucker, addresses longstanding and emergent cruxes in our collective scholarship, including questions of periodization, mediality, trans/nationality, genre, and mode. “Romance” and “realism” provide two provoking terms for thought. An introduction, by Elaine Freedgood and N. Maureen McLane, lays out axes of categorization, questions for pedagogy and the profession as well as intellectual and disciplinary genealogies. Duncan notes the insufficiency of such terms as “long nineteenth century” and proposes Walter Scott as one figure who teaches us how to think period as well as realism and romance; Favret addresses the romantic lecture and its current resonance in the age of MOOCs; Robson explores the nature of Victorian reading, and directions for Victorianist readings; Tucker meditates on the status of desire and marriage plots—Romantic and Victorian “conjugalities.”
Identification des rôles que s’attribuent les enseignants associés jumelés à des stagiaires en enseignement de l’éducation physique qui ont développé leur sentiment d’efficacité personnelle à la suite d’un stage
Authors: Monfette Olivia , Grenier Johanne
Published: July 2014

Le stage est un moment déterminant dans le développement du sentiment d’efficacité personnelle (SEP) des stagiaires et l’enseignant associé (EA) peut y jouer un rôle important. Cet article présente l’identification des rôles que s’attribuent sept EA qui ont accueilli des stagiaires dont le SEP s’est développé ou maintenu à la suite du stage. L’analyse des propos recueillis lors d’entretiens semi-dirigés permet de constater que les EA considèrent quatre dimensions primordiales soit : offrir des occasions d’autodéveloppement, échanger des idées, établir de bonnes relations avec les stagiaires et transmettre leur savoir. Les EA semblent avoir utilisés les expériences actives de maîtrise, les expériences vicariantes et la persuasion verbale comme méthodes d’accompagnement auprès de leurs stagiaires.
Research From the Global South: The important role of context in international research activities
Authors: Bryant Katie
Published: July 2014

Researchers from various disciplines have become interested in the supposedly extreme differences in rates of research between academics situated in the Global North and South, specifically those on the African continent. Yet, having worked as a researcher and a writing coach in the context of one university in the southern African region for the past three years, I cannot identify with many of the explanations given for these differences in rates. So, by reflecting on two instances emerging from my own experiences as a researcher in this particular context, this Note from the Field discusses the important and critical role context needs to have in making sense of this phenomenon.
Redox signaling via the molecular chaperone BiP protects cells against endoplasmic reticulum-derived oxidative stress
Authors: Wang Jie , Pareja Kristeen A , Kaiser Chris A , Sevier Carolyn S
Published: July 2014

Oxidative protein folding in the endoplasmic reticulum (ER) has emerged as a potentially significant source of cellular reactive oxygen species (ROS). Recent studies suggest that levels of ROS generated as a byproduct of oxidative folding rival those produced by mitochondrial respiration. Mechanisms that protect cells against oxidant accumulation within the ER have begun to be elucidated yet many questions still remain regarding how cells prevent oxidant-induced damage from ER folding events. Here we report a new role for a central well-characterized player in ER homeostasis as a direct sensor of ER redox imbalance. Specifically we show that a conserved cysteine in the lumenal chaperone BiP is susceptible to oxidation by peroxide, and we demonstrate that oxidation of this conserved cysteine disrupts BiP's ATPase cycle. We propose that alteration of BiP activity upon oxidation helps cells cope with disruption to oxidative folding within the ER during oxidative stress.
Quantitative analysis of mammalian GIRK2 channel regulation by G proteins, the signaling lipid PIP2 and Na+ in a reconstituted system
Authors: Wang Weiwei , Whorton Matthew R , MacKinnon Roderick
Published: July 2014

GIRK channels control spike frequency in atrial pacemaker cells and inhibitory potentials in neurons. By directly responding to G proteins, PIP2 and Na+, GIRK is under the control of multiple signaling pathways. In this study, the mammalian GIRK2 channel has been purified and reconstituted in planar lipid membranes and effects of Gα, Gβγ, PIP2 and Na+ analyzed. Gβγ and PIP2 must be present simultaneously to activate GIRK2. Na+ is not essential but modulates the effect of Gβγ and PIP2 over physiological concentrations. Gαi1(GTPγS) has no effect, whereas Gαi1(GDP) closes the channel through removal of Gβγ. In the presence of Gβγ, GIRK2 opens as a function of PIP2 mole fraction with Hill coefficient 2.5 and an affinity that poises GIRK2 to respond to natural variations of PIP2 concentration. The dual requirement for Gβγ and PIP2 can help to explain why GIRK2 is activated by Gi/o, but not Gq coupled GPCRs.
Mapping Europe's Seismic Hazard
Authors: Giardini Domenico , Wössner Jochen , Danciu Laurentiu
Published: July 2014

From the rift that cuts through the heart of Iceland to the complex tectonic convergence that causes frequent and often deadly earthquakes in Italy, Greece, and Turkey to the volcanic tremors that rattle the Mediterranean, seismic activity is a prevalent and often life‐threatening reality across Europe. Any attempt to mitigate the seismic risk faced by society requires an accurate estimate of the seismic hazard.
Reducing Rockfall Risk in Yosemite National Park
Authors: Stock Greg M. , Collins Brian D.
Published: July 2014

Yosemite National Park preserves some of the world's most spectacular geological scenery, including icons such as Half Dome and El Capitan. The glacially sculpted granite walls of Yosemite Valley attract 4 million visitors a year, but rockfalls from these cliffs pose substantial hazards (Figure 1).
Nuclear Waste Disposal: A Cautionary Tale for Shale Gas Development
Authors: Alley William M. , Cherry John A. , Parker Beth L. , Ryan M. Cathryn
Published: July 2014

Nuclear energy and shale gas development each began with the promise of cheap, abundant energy and prospects for national energy independence. Nuclear energy was touted as “too cheap to meter,” and shale gas promised jobs and other economic benefits during a recession.
Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Citation for Paul A. Ginoux
Authors: Webster Peter J.
Published: July 2014

The Atmospheric Sciences section of AGU awards one of the five Ascent Awards to Dr. Paul A. Ginoux of the Geophysical Fluid Dynamics Laboratory (GFDL) at the National Oceanic and Atmospheric Administration for outstanding world‐leading research on dust aerosols using observations and models that has contributed to a comprehensive scientific understanding of atmospheric aerosols.”
Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Citation for Mark Z. Jacobson
Authors: Webster Peter J.
Published: July 2014

The Atmospheric Sciences section of AGU awards one of the five Ascent Awards to Professor Mark Z. Jacobson of the Department of Civil and Environmental Engineering at Stanford University for his dominating role in the development of models to identify the role of black carbon in climate change.
Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Response
Authors: Nizkorodov Sergey
Published: July 2014

I am truly honored to accept the Ascent Award from the Atmospheric Sciences section of AGU. The amazingly dynamic and intellectually stimulating atmospheric sciences community always makes my annual trips to the AGU Fall Meeting a real treat. I feel really fortunate to be a member of this vibrant community.
Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Citation for Ping Yang
Authors: Webster Peter J.
Published: July 2014

The Atmospheric Sciences section of AGU awards one of the five Ascent Awards to Professor Ping Yang of the Department of Atmospheric Sciences at Texas A&M University for significant contributions to atmospheric scattering, radiative transfer, and remote sensing.
Large channels perforate underside of Antarctica's Fimbul Ice Shelf
Authors: Schultz Colin
Published: July 2014

In November 2010 Langley et al. used ground‐penetrating radar to capture high‐resolution measurements of the internal structure of the Fimbul Ice Shelf, a roughly 200 by 100 kilometer sheet of ice that floats off the coast of eastern Antarctica. They found that the ice shelf appears to be decaying from below. At the glacier‐ocean boundary, the ice is perforated by a network of channels, grooves cut into the ice that are as wide as the glacier is thick.
Stream and groundwater interactions affect streambed water fluxes
Authors: Schultz Colin
Published: July 2014

Just beneath the sediment surface of a streambed is the hyporheic zone, where stream water and groundwater mix. The hyporheic zone is a hot spot for chemical and biological processes. How water moves into and out of the hyporheic zone is an important factor controlling the biogeochemistry and biology of the stream ecosystem.
Synthetic greenhouse gases to decline if Montreal Protocol amended
Authors: Wendel JoAnna
Published: July 2014

The Montreal Protocol, an international treaty designed to reduce the release into the atmosphere of ozone‐depleting gases such as hydrochlorofluorocarbons and chlorofluorocarbons, has been successful since its implementation in the late 1980s. However, related greenhouse gases, such as hydrofluorocarbons (HFCs), have increased in concentration in the atmosphere since then. HFCs, along with other synthetic greenhouse gases (SGHGs), account for a radiative forcing almost 20% as large as that due to the increase in carbon dioxide (CO2) since the preindustrial era.
Evolution of stress and fault patterns in oblique rift systems: 3‐D numerical lithospheric‐scale experiments from rift to breakup
Authors: Brune Sascha
Published: July 2014

Rifting involves complex normal faulting that is controlled by extension direction, reactivation of prerift structures, sedimentation, and dyke dynamics. The relative impact of these factors on the observed fault pattern, however, is difficult to deduce from field‐based studies alone. This study provides insight in crustal stress patterns and fault orientations by employing a laterally homogeneous, 3‐D rift setup with constant extension velocity. The presented numerical forward experiments cover the whole spectrum of oblique extension. They are conducted using an elastoviscoplastic finite element model and involve crustal and mantle layers accounting for self‐consistent necking of the lithosphere. Despite recent advances, 3‐D numerical experiments still require relatively coarse resolution so that individual faults are poorly resolved. This issue is addressed by applying a post processing method that identifies the stress regime and preferred fault azimuth at each surface element. The simple model setup results in a surprising variety of fault orientations that are solely caused by the three‐dimensionality of oblique rift systems. Depending on rift obliquity, these orientations can be grouped in terms of rift‐parallel, extension‐orthogonal, and intermediate normal fault directions as well as strike‐slip faults. While results compare well with analog rift models of low to moderate obliquity, new insight is gained in advanced rift stages and highly oblique settings. Individual fault populations are activated in a characteristic multiphase evolution driven by lateral density variations of the evolving rift system. In natural rift systems, this pattern might be modified by additional heterogeneities, surface processes, and dyke dynamics.
Effect of Nano‐Porosity on High Gain Permeable Metal‐Base Transistors
Authors: Yu Hyeonggeun , Kim Jong H. , Chen Wenchao , Kim Doyoung , Guo Jing , So Franky
Published: July 2014

As one type of vertical thin‐film transistors, permeable metal‐base transistors (PMBTs) with a permeable metal film embedded between two semiconductor layers have been proposed for high gain current amplifier. In principle, compared with conventional bipolar transistors, PMBTs should have a higher speed and are easier to fabricate compatible with flexible and printed electronics. However, functional PMBTs are not realized due to low current gains (<50) and lack of output current saturation. In this paper, making use of the nano‐textured surface of an organic semiconductor, we are able to fabricate devices with permeable metal base films having a pore size of about 20 nm and achieve current gains up to 476 with output current saturation. Correlations between the nano‐scale porosity and the charge transmission/amplification behaviors in the device are explained with characterization of the metal base porosity. From our device simulation results, the small pore size is essential to achieve current saturation in the device due to the potential‐pinning effect in the small pore regions. Finally, using a similar strategy, we also demonstrate a high gain (=260) solution‐processed metal oxide‐based PMBTs with output current saturation.
Performance and Stability Enhancement of Dye‐Sensitized and Perovskite Solar Cells by Al Doping of TiO2
Authors: Pathak Sandeep K. , Abate A. , Ruckdeschel P. , Roose B. , Gödel Karl C. , Vaynzof Yana , Santhala Aditya , Watanabe Shun‐Ichiro , Hollman Derek J. , Noel Nakita , Sepe Alessandro , Wiesner Ullrich , Friend Richard , Snaith Henry J. , Steiner Ullrich
Published: July 2014

Reversible photo‐induced performance deterioration is observed in mesoporous TiO2‐containing devices in an inert environment. This phenomenon is correlated with the activation of deep trap sites due to astoichiometry of the metal oxide. Interestingly, in air, these defects can be passivated by oxygen adsorption. These results show that the doping of TiO2 with aluminium has a striking impact upon the density of sub‐gap states and enhances the conductivity by orders of magnitude. Dye‐sensitized and perovskite solar cells employing Al‐doped TiO2 have increased device efficiencies and significantly enhanced operational device stability in inert atmospheres. This performance and stability enhancement is attributed to the substitutional incorporation of Al in the anatase lattice, “permanently” passivating electronic trap sites in the bulk and at the surface of the TiO2.
Upward Trend in Catalytic Efficiency of Rare‐Earth Triflate Catalysts in Friedel–Crafts Aromatic Sulfonylation Reactions
Authors: Nguyen Vo Thu An , Duus Fritz , Le Thach Ngoc
Published: July 2014

A series of 14 lanthanide (Ln) triflates were investigated as sustainable catalysts for aromatic sulfonylation reactions under microwave irradiation. The catalytic efficiency of the early triflates La(OTf)3–Eu(OTf)3 is good for long irradiation times. For the later lanthanides, yields reaching over 90 % were achieved for short irradiation periods. This was the case especially for Tm(OTf)3, Yb(OTf)3, and Lu(OTf)3, of which Yb(OTf)3 was the most efficient. The upward trend in catalytic efficiency therefore correlates with the lanthanide sequence in the periodic table. The results can be explained by the decrease in the radii of the Ln3+ ions, and the hydrolysis and water‐exchanges rate within the series. The results are in agreement with the first principal property value (t1) calculated by principal component analysis (PCA) published previously. A large drop in sulfonylation yield was obtained with Gd(OTf)3, which matched the “gadolinium break”; the well‐known discontinuity in lanthanide properties.
Coordination‐Driven In Situ Self‐Assembly Strategy for the Preparation of Metal–Organic Framework Hybrid Membranes
Authors: Zhang Rong , Ji Shulan , Wang Naixin , Wang Lin , Zhang Guojun , Li Jian‐Rong
Published: July 2014

Metal–organic frameworks (MOFs) have emerged as porous solids of a superior type for the fabrication of membranes. However, it is still challenging to prepare a uniformly dispersed robust MOF hybrid membrane. Herein, we propose a simple and powerful strategy, namely, coordination‐driven in situ self‐assembly, for the fabrication of MOF hybrid membranes. On the basis of the coordination interactions between metal ions and ligands and/or the functional groups of the organic polymer, this method was confirmed to be feasible for the production of a stable membrane with greatly improved MOF‐particle dispersion in and compatibility with the polymer, thus providing outstanding separation ability. As an experimental proof of concept, a high‐quality ZIF‐8/PSS membrane was fabricated that showed excellent performance in the nanofiltration and separation of dyes from water.
Synthesis of a Dimeric Magnesium(I) Compound by an MgI/MgII Redox Reaction
Authors: Stasch Andreas
Published: July 2014

The synthesis of dimeric magnesium(I) compounds of the general type RMgMgR (R=monoanionic substituent) is still a challenging synthetic task and limited to few examples with sterically demanding ligands with delocalized CN‐frameworks that all have been accessed by Na or K metal reduction of magnesium(II) halide precursors. Here we report on the synthesis of a novel diiminophosphinato magnesium(I) compound that has been synthesized by a facile redox reaction using a known magnesium(I) complex. The synthetic strategy may be applicable to other ligand systems and can help expand the class of low oxidation state magnesium complexes even if reductions with Na or K are unsuccessful. The new dimeric magnesium(I) complex has been structurally characterized and undergoes a CC coupling reaction with tert‐butylisocyanate.
Unprecedented Role of Hydronaphthoquinone Tautomers in Biosynthesis
Authors: Husain Syed Masood , Schätzle Michael A. , Lüdeke Steffen , Müller Michael
Published: July 2014

Quinones and hydroquinones are among the most common cellular cofactors, redox mediators, and natural products. Here, we report on the reduction of 2‐hydroxynaphthoquinones to the stable 1,4‐diketo tautomeric form of hydronaphthoquinones and their further reduction by fungal tetrahydroxynaphthalene reductase. The very high diastereomeric and enantiomeric excess, together with the high yield of cis‐3,4‐dihydroxy‐1‐tetralone, exclude an intermediary hydronaphthoquinone. Labeling experiments with NADPH and NADPD corroborated the formation of an unexpected 1,4‐diketo tautomeric form of 2‐hydroxyhydronaphthoquinone as a stable intermediate. Similar 1,4‐diketo tautomers of hydronaphthoquinones were established as products of the NADPH‐dependent enzymatic reduction of other 1,4‐naphthoquinones, and as substrates for different members of the superfamily of short‐chain dehydrogenases. We propose an essential role of hydroquinone diketo tautomers in biosynthesis and detoxification processes.
Understanding a Host–Guest Model System through 129Xe NMR Spectroscopic Experiments and Theoretical Studies
Authors: Dubost Emmanuelle , Dognon Jean‐Pierre , Rousseau Bernard , Milanole Gaëlle , Dugave Christophe , Boulard Yves , Léonce Estelle , Boutin Céline , Berthault Patrick
Published: July 2014

Gaining an understanding of the nature of host–guest interactions in supramolecular complexes involving heavy atoms is a difficult task. Described herein is a robust simulation method applied to complexes between xenon and members of a cryptophane family. The calculated chemical shift of xenon caged in a H2O2 probe, as modeled by quantum chemistry with complementary‐orbital, topological, and energy‐decomposition analyses, is in excellent agreement with that observed in hyperpolarized 129Xe NMR spectra. This approach can be extended to other van der Waals complexes involving heavy atoms.
An “All‐Green” Catalytic Cycle of Aqueous Photoionization
Authors: Goez Martin , Kerzig Christoph , Naumann Robert
Published: July 2014

Hydrated electrons are highly aggressive species that can force chemical transformations of otherwise unreactive molecules such as the reductive detoxification of halogenated organic compounds. We present the first example of the sustainable production of hydrated electrons through a homogeneous catalytic cycle driven entirely by green light (532 nm, coinciding with the maximum of the terrestrial solar spectrum). The catalyst is a metal complex serving as a “container” for a radical anion. This active center is generated from a ligand through quenching by a sacrificial electron donor, is shielded by the complex such that it stores the energy of the photon for much longer than a free radical anion could, and is finally ionized by another photon to regenerate the ligand and recover the starting complex quantitatively. The sacrificial donor can be a bioavailable reagent such as ascorbic acid.
Integrating Perovskite Solar Cells into a Flexible Fiber
Authors: Qiu Longbin , Deng Jue , Lu Xin , Yang Zhibin , Peng Huisheng
Published: July 2014

Perovskite solar cells have triggered a rapid development of new photovoltaic devices because of high energy conversion efficiencies and their all‐solid‐state structures. To this end, they are particularly useful for various wearable and portable electronic devices. Perovskite solar cells with a flexible fiber structure were now prepared for the first time by continuously winding an aligned multiwalled carbon nanotube sheet electrode onto a fiber electrode; photoactive perovskite materials were incorporated in between them through a solution process. The fiber‐shaped perovskite solar cell exhibits an energy conversion efficiency of 3.3 %, which remained stable on bending. The perovskite solar cell fibers may be woven into electronic textiles for large‐scale application by well‐developed textile technologies.
Degradation behavior of ionic‐covalent entanglement hydrogels
Authors: De Silva D. Awanthi , Martens Penny J. , Gilmore Kerry J. , in het Panhuis Marc
Published: July 2014

Ionic‐covalent entanglement (ICE) hydrogels are a recently introduced new type of robust materials for potential future application in the fields of tissue engineering and soft robotics. Here the degradation behavior of gellan gum/polyacrylamide ICE hydrogels immersed in PBS or enzyme solutions is presented. It is demonstrated that ICE gels immersed in enzymes became stiffer, whereas under cyclic testing their mechanical responses stabilize after 10 loading/unloading cycles whether immersed in PBS or enzyme solutions. The leachates of the ICE hydrogels were found to be non‐cytotoxic for the growth of L929 and PC12 cells. These findings will be of benefit to the future development of tissue engineering applications based on these gel materials. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 41216.
Collective Synthesis of 4‐Hydroxy‐2‐pyridone Alkaloids and Their Antiproliferation Activities
Authors: Ding Feiqing , Leow Min Li , Ma Jimei , William Ronny , Liao Hongze , Liu Xue‐Wei
Published: July 2014

A collective synthesis of 4‐hydroxy‐2‐pyridone alkaloids—specifically, pretenellin B, prebassianin B, farinosone A, militarione D, pyridovericin, and torrubiellone C—has been achieved. Key steps include using a strategic convergent method to synthesize the densely substituted pyridone key intermediate by Suzuki–Miyaura cross‐coupling reaction, a divergent synthesis approach of target molecules by aldol condensation of pyridone intermediate with homologous aldehydes, and an iterative synthesis of homologous aldehydes with all‐trans‐polyene backbones. Interestingly, among the six tumor cell lines investigated, torrubiellone C was found to induce potent and apoptotic inhibitory activities on Jurkat T cells with IC50 values of 7.05 μM. Hence, this approach could potentially contribute to the synthesis of bioactive small‐molecule libraries as well as drug discovery.
Reactions of Cycloaliphatic Thioketones and Their Oxo Analogues with Lithiated Methoxyallene: A New Approach to Vinylthiiranes
Authors: Jasiński Marcin , Mlostoń Grzegorz , Stolarski Michał , Costa Wilhelmine , Domínguez Moises , Reissig Hans‐Ulrich
Published: July 2014

Admantanethione smoothly reacted with lithiated methoxyallene at low temperatures yielding the expected allenyl‐substituted thiolate, which upon aqueous work‐up underwent spontaneous 1,3‐cyclization to afford a hitherto unknown methoxy‐substituted vinylthiirane derivative. The analogous reaction with adamantanone led to the corresponding allenyl alcohol that can be isolated and—depending on the conditions applied—either be converted into the corresponding vinyloxirane or into the 2,5‐dihydrofuran derivative. Sterically more crowded thioketones were also combined with lithiated methoxyallene, but in these cases competitive 1,5‐cyclization leading to isomeric dihydrothiophene derivatives was observed. DFT calculations of model intermediates and products show distinct energy differences of the sulfur and the corresponding oxygen compounds. Desulfurization of the adamantanethione‐derived vinylthiirane yielded a methoxy‐substituted 1,3‐diene that was studied in cycloadditions with electron‐deficient dienophiles. Whereas in the case of tetracyanoethylene the corresponding cyclobutane derivative was formed, the reaction with nitrosobenzene provided the expected 1,2‐oxazine derivative. By reductive cleavage of the NO bond this heterocycle was converted into an unsaturated amino alcohol bearing an adamantane moiety.
Outcomes after endovascular or open repair for degenerative descending thoracic aortic aneurysm using linked hospital data
Authors: von Allmen R S , Anjum A , Powell J T
Published: July 2014

Background

The population-based effectiveness of thoracic endovascular aortic repair (TEVAR) versus open surgery for descending thoracic aortic aneurysm remains in doubt.

Methods

Patients aged over 50 years, without a history of aortic dissection, undergoing repair of a thoracic aortic aneurysm between 2006 and 2011 were assessed using mortality-linked individual patient data from Hospital Episode Statistics (England). The principal outcomes were 30-day operative mortality, long-term survival (5 years) and aortic-related reinterventions. TEVAR and open repair were compared using crude and multivariable models that adjusted for age and sex.

Results

Overall, 759 patients underwent thoracic aortic aneurysm repair, mainly for intact aneurysms (618, 81·4 per cent). Median ages of TEVAR and open cohorts were 73 and 71 years respectively (P < 0·001), with more men undergoing TEVAR (P = 0·004). For intact aneurysms, the operative mortality rate was similar for TEVAR and open repair (6·5 versus 7·6 per cent; odds ratio 0·79, 95 per cent confidence interval (c.i.) 0·41 to 1·49), but the 5-year survival rate was significantly worse after TEVAR (54·2 versus 65·6 per cent; adjusted hazard ratio 1·45, 95 per cent c.i. 1·08 to 1·94). After 5 years, aortic-related mortality was similar in the two groups, but cardiopulmonary mortality was higher after TEVAR. TEVAR was associated with more aortic-related reinterventions (23·1 versus 14·3 per cent; adjusted HR 1·70, 95 per cent c.i. 1·11 to 2·60). There were 141 procedures for ruptured thoracic aneurysm (97 TEVAR, 44 open), with TEVAR showing no significant advantage in terms of operative mortality.

Conclusion

In England, operative mortality for degenerative descending thoracic aneurysm was similar after either TEVAR or open repair. Patients who had TEVAR appeared to have a higher reintervention rate and worse long-term survival, possibly owing to cardiopulmonary morbidity and other selection bias.
Factors influencing aversion to specific electrodiagnostic studies
Authors: Jerath Nivedita U. , Strader Scott B. , Reddy Chandan G. , Swenson Andrea , Kimura Jun , Aul Edward
Published: July 2014

Objective

To compare the degree of discomfort caused by nerve conduction studies (NCS) versus needle electromyography (EMG), and to determine what factors predict aversion to one test or the other.

Methods

Two hundred patients underwent both EMG and NCS, and were asked to indicate which test was more uncomfortable. Responses were then correlated with demographic information, testing characteristics, and medical histories to identify any notable associations.

Results

Of the 200 patients, 58.5% (117) of the patients found the NCS more uncomfortable than EMG. Sixty‐one percent (11/18) of the younger patients (18–29 years old) found EMG more uncomfortable (P = 0.08), whereas 68% (40/59) of the older patients (age greater than 60 years old) found NCS more uncomfortable (P = 0.05). Sixty‐seven percent (14/21) of the patients whose BMI was less than 22 kg/m2 rated EMG as more uncomfortable (P = 0.01). Sixty‐nine percent (27/39) of the patients whose BMI was greater than or equal to 38 found the NCS more uncomfortable (P = 0.02). A positive correlation existed between NCS discomfort and number of nerves tested. 67% (35/52) of the patients with polyneuropathy found NCS more uncomfortable.

Conclusion

Nerve conduction studies are more uncomfortable than needle EMG in the majority of patients, and predictions regarding which test will be more uncomfortable for a given patient are possible.
Self‐Assembly of Fullerene‐Based Janus Particles in Solution: Effects of Molecular Architecture and Solvent
Authors: Lin Zhiwei , Lu Pengtao , Hsu Chih‐Hao , Yue Kan , Dong Xue‐Hui , Liu Hao , Guo Kai , Wesdemiotis Chrys , Zhang Wen‐Bin , Yu Xinfei , Cheng Stephen Z. D.
Published: July 2014

Two molecular Janus particles based on amphiphilic [60]fullerene (C60) derivatives were designed and synthesized by using the regioselective Bingel–Hirsh reaction and the click reaction. These particles contain carboxylic acid functional groups, a hydrophilic fullerene (AC60), and a hydrophobic C60 in different ratios and have distinct molecular architectures: 1:1 (AC60–C60) and 1:2 (AC60–2C60). These molecular Janus particles can self‐assemble in solution to form aggregates with various types of micellar morphology. Whereas vesicular morphology was observed for both AC60–C60 and AC60–2C60 in tetrahydrofuran, in a mixture of N,N‐dimethylformamide (DMF)/water, spherical micelles and cylindrical micelles were observed for AC60–C60 and AC60–2C60, respectively. A mechanism of formation was tentatively proposed based on the effects of molecular architecture and solvent polarity on self‐assembly.
Pd‐Catalysed Mono‐ and Dicarbonylation of Aryl Iodides: Insights into the Mechanism and the Selectivity
Authors: Fernández‐Alvarez Victor M. , de la Fuente Verónica , Godard Cyril , Castillón Sergio , Claver Carmen , Maseras Feliu , Carbó Jorge J.
Published: July 2014

The mechanism of the experimentally reported phosphine‐free palladium‐catalysed carbonylation of aryl iodides with amines in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) as base was investigated at the DFT level. Paths were identified for both di‐ and monocarbonylation, and the calculated selectivity for three different substrates was in agreement with experiment. In dicarbonylation yielding α‐ketoamides, formation of the second carbon–carbon bond occurs through reductive elimination in the Pd acyl amide intermediate after DBU‐assisted nucleophilic attack of an amine at a terminal CO ligand. This path yields the major product with iodobenzene and the almost exclusive product with p‐methoxyiodobenzene. Two different possible pathways yield the monocarbonylated amide product. In one of them, which affords the minor product for iodobenzene, base‐assisted nucleophilic attack of the amine takes place on a Pd‐bound acyl ligand. For substrates with electron‐withdrawing substituents, such as p‐cyanoiodobenzene, aryl migration to the CO ligand is disfavoured, and this allows base‐assisted amine attack at a terminal CO ligand early in the catalytic cycle. From the resulting Pd amide aryl complex, the subsequent reductive elimination occurs easily, and monocarbonylation becomes favoured.
Stabilization of a Two‐Coordinate Mononuclear Cobalt(0) Compound
Authors: Mondal Kartik Chandra , Roy Sudipta , De Susmita , Parameswaran Pattiyil , Dittrich Birger , Ehret Fabian , Kaim Wolfgang , Roesky Herbert W.
Published: July 2014

Compound (Me2‐cAAC:)2Co0 (2; Me2‐cAAC:=cyclic (alkyl) amino carbene; :C(CH2)(CMe2)2N‐2,6‐iPr2C6H3) was synthesized by the reduction of the precursor (Me2‐cAAC:)2CoICl (1) with KC8 in THF. The cyclic voltammogram of 1 exhibited one‐electron reduction, which suggests that synthesis of a bent 2‐metallaallene (2) from 1 should be possible. Compound 2 contains one cobalt atom in the formal oxidation state zero, which is stabilized by two Me2‐cAAC: ligands. Bond lengths from X‐ray diffraction are 1.871(2) and 1.877(2) Å with a C‐Co‐C bond angle of 170.12(8)°. The EPR spectrum of 2 exhibited a broad resonance attributed to the unique quasi‐linear structure, which favors near degeneracy and gives rise to very rapid relaxation conditions. The cAACCo bond in 2 can be considered as a typical Dewar–Chatt–Duncanson type of bonding, which in turn retains 2.5 electron pairs on the Co atom as nonbonding electrons.
Drebrin inhibits cofilin‐induced severing of F‐actin
Authors: Grintsevich Elena E. , Reisler Emil
Published: July 2014

Molecular cross‐talk between neuronal drebrin A and cofilin is believed to be a part of the activity‐dependent cytoskeleton‐modulating pathway in dendritic spines. Impairments in this pathway are implicated also in synaptic dysfunction in Alzheimer's disease, Down syndrome, epilepsy, and normal aging. However, up to now the molecular interplay between cofilin and drebrin has not been elucidated. TIRF microscopy and solution experiments revealed that full length drebrin A or its actin binding core (Drb1‐300) inhibits, but do not abolish cofilin‐induced severing of actin filaments. Cosedimentation experiments showed that F‐actin can be fully occupied with combination of these two proteins. The dependence of cofilin binding on fractional saturation of actin filaments with drebrin suggests direct competition between these two proteins for F‐actin binding. This implies that cofilin and drebrin can either overcome or reverse the allosteric changes in F‐actin induced by the competitor's binding. The ability of cofilin to displace drebrin from actin filaments is pH dependent and is facilitated at acidic pH (6.8). Pre‐steady state kinetic experiments reveal that both binding and dissociation of drebrin to/from actin filaments is faster than that reported for cooperative binding of cofilin. We found, that drebrin displacement by cofilin is greatly inhibited when actin severing is abolished, which might be linked to the cooperativity of drebrin binding to actin filaments. Our results contribute to molecular understanding of the competitive interactions of drebrin and cofilin with actin filaments. © 2014 Wiley Periodicals, Inc.
Effects of experimental sedimentation on the phenological dynamics and leaf traits of replanted mangroves at Gazi bay, Kenya
Authors: Okello Judith A. , Robert Elisabeth M. R. , Beeckman Hans , Kairo James G. , Dahdouh‐Guebas Farid , Koedam Nico
Published: July 2014

Sedimentation results in the creation of new mudflats for mangroves to colonize among other benefits. However, large sediment input in mangrove areas may be detrimental to these forests. The dynamics of phenological events of three mangrove tree species (Avicennia marina, Ceriops tagal, and Rhizophora mucronata) were evaluated under experimental sediment burial simulating sedimentation levels of 15, 30, and 45 cm.

While there was generally no shift in timing of phenological events with sedimentation, the three mangrove tree species each responded differently to the treatments.

Partially buried A. marina trees produced more leaves than the controls during the wet season and less during the dry season. Ceriops tagal on the other hand had higher leaf loss and low replacement rates in the partially buried trees during the first 6 months of the experiment but adapted with time, resulting in either equal or higher leaf emergence rates than the controls.

Rhizophora mucronata maintained leaf emergence and loss patterns as the unaffected controls but had a higher fecundity and productivity in the 15‐cm sedimentation level.

The results suggest that under incidences of large sedimentation events (which could be witnessed as a result of climate change impacts coupled with anthropogenic disturbances), mangrove trees may capitalize on “advantages” associated with terrestrial sediment brought into the biotope, thus maintaining the pattern of phenological events.
Mixed‐Donor Amido–Siloxo Actinide(IV) Halide and Alkyl Complexes with an Aryl Cipso Interaction
Authors: Hayes Cassandra E. , Gill Dayle E. , Brown Matthew L. , Leznoff Daniel B.
Published: July 2014

The synthesis and characterisation of a series of new actinide(IV) complexes supported by the mixed‐donor amido–amino–siloxo framework [RN(Li)SiMe2N(R)SiMe2OLi] ([RNNO]Li2; R = 2,4,6‐Me3Ph, 2,6‐iPr2Ph) are presented. The reaction of 1 equiv. of [RNNO]Li2 with ThCl4·2DME (DME = 1,2‐dimethoxyethane) in DME generated {Li·nDME}{[RNNO]2Th2Cl5} (1: R = 2,4,6‐Me3Ph, n = 2; 2: R = 2,6‐iPr2Ph, n = 3) in high yield, and the addition of [NNO]Li2 to UCl4 in tetrahydrofuran (THF) resulted in the formation of {[NNO]UCl3Li·THF}2 (3). The structures of 1–3 indicate that they retain LiCl as “ate” complexes. The addition of 2 equiv. of [NNO]Li2 to ThCl4·2DME and UCl4 gives the bis‐ligated complexes [NNO]2ThClLi (4) and [NNO]2U (5), respectively. In 1–5, the [RNNO]2– ligands all coordinate through the amido and siloxo donors as well as the ipso carbon atom of the phenyl group of the amido ligand but not through the central amino group. Complex 3 can be alkylated through the addition of 2 equiv. of LiCH2SiMe3 to give [NNO]U(CH2SiMe3)2 (6) or NaCp (Cp = cyclopentadienyl) to give [NNO]UCp2 (7); the latter has been structurally characterised.
Synthesis, Stability, and Photoreactivity of Diazirinyl‐SubstitutedN‐Heterocycles Based on Indole, Benzimidazole, and Imidazole
Authors: Raimer Björn , Wartmann Thomas , Jones Peter G. , Lindel Thomas
Published: July 2014

The synthesis, thermal stability, and photoreactivity of trifluoromethyl diazirines installed at the heterocyclic section ofN‐methylindole,N‐methylbenzimidazole, and atN‐methylimidazole were investigated.N‐Tosyl‐3‐diazirinylindole andN‐methyl‐2‐diazirinylbenzimidazole proved to be thermally stable, whereas the corresponding 2‐diazirinylindole was not. The least stable was 2‐diazirinylimidazole, which underwent rapid decomposition. Quenching with ethanol indicated that the corresponding carbene was formed. Decomposition is rationalized by exothermic coarctate ring‐opening of the carbene. Quantum mechanical calculations [B3LYP/6‐311G(2d,2p)] predict singlet ground states of all carbenes. Accordingly, Friedel–Crafts alkylation products were formed on irradiation (350 nm, Rayonet) of theN‐methylbenzimidazole‐based diazirine in the presence of phenol.
Electrochemical Deoxygenation of Aromatic Amides and Sulfoxides
Authors: Edinger Carolin , Waldvogel Siegfried R.
Published: July 2014

The electrochemical deoxygenation of a broad range of aromatic amides was achieved under mild conditions on lead cathodes. Under the optimized reaction conditions, acetal, thienyl, and ether moieties are tolerated. Furthermore, the reduction protocol can be applied to aromatic and aliphatic sulfoxides to obtain the corresponding sulfides. For both aromatic amides and sulfoxides, the deoxygenation reaction ensues without the use of expensive catalysts or hazardous reducing agents. Owing to the high selectivity of the process, simple extraction is sufficient to isolate the product from the substrate. The straightforward purification protocol, the coformation of water, and the use of electric current instead of reducing agents render our method environmentally friendly and economically beneficial.
Natural Gas Production: Debtor Fails in Attempt to Use Bankruptcy for Fracking Profits
Authors: Sabino Anthony Michael
Published: July 2014

Lately, we have, quite naturally, devoted a great deal of our writing to the paramount issue of fracking, as it resides on the cutting edge of the natural gas industry.
End‐Users: Apps Present Better Customer Communications for Utilities
Authors:   iFactor Consulting
Published: July 2014

Exposure to leading‐edge communication technology tends to create a sense that this technology is widely used, even normal. Communication technology is definitely becoming more common and has become nearly universal among some groups (at least in the United States). However, a deeper look at technology adoption rates reminds us that the situation is more complex than the averages indicate.