bluuebunny/crossref_metadata_2025_split huggingface dataset:
Potential predictability sources of the 2012 U.S. drought in observations and a regional model ensemble
Authors: PaiMazumder Debasish , Done James M. 
Published: September 2016

AbstractThe 2012 drought was the most severe and extensive summertime U.S. drought in half a century with substantial economic loss and impacts on food security and commodity prices. A unique aspect of the 2012 drought was its rapid onset and intensification over the Southern Rockies, extending to the Great Plains during late spring and early summer, and the absence of known precursor large‐scale patterns. Drought prediction therefore remains a major challenge. This study evaluates relationships among snow, soil moisture, and precipitation to identify sources of potential predictability of the 2012 summer drought using observations and a Weather Research and Forecasting model multiphysics ensemble experiment. Although underestimated in intensity, the drought signal is robust to the way atmospheric physical processes are represented in the model. For the Southern Rockies, soil moisture exhibits stronger persistence than precipitation in observations and the ensemble experiment. Correlations between winter/spring snowmelt and concurrent and following season soil moisture, and between soil moisture and concurrent and following season precipitation, in both observations and the model ensemble, suggest potential predictability beyond 1 and 2 month lead‐time reside in the land surface conditions for apparent flash droughts such as the 2012 drought.
Behavior of dissolved radiocesium in river water in a forested watershed in Fukushima Prefecture
Authors: Tsuji H. , Nishikiori T. , Yasutaka T. , Watanabe M. , Ito S. , Hayashi S. 
Published: September 2016

AbstractDissolved radiocesium concentrations in river water in a high‐dose‐rate forest watershed in Fukushima Prefecture were investigated under base flow and storm flow conditions. Under base flow conditions, dissolved 137Cs concentrations in water (Bq/L) were relatively high in summer, and these levels were higher than particulate 137Cs concentrations (Bq/L). Under storm flow, particulate 137Cs concentration became dominant as the suspended solid concentration increased. Throughout the monitoring period, dissolved 137Cs concentrations in water (Bq/L) were higher under storm flow than base flow conditions and were positively correlated with runoff intensity. Factors influencing changes in dissolved 137Cs concentrations were investigated by measuring the 137Cs concentration of suspended solid (Bq/kg) and dissolved 137Cs of unsaturated soil water, throughfall, and rainfall, together with other main solute concentrations. The 137Cs concentration per unit weight of suspended solids in river water was not strongly correlated with runoff intensity. Additionally, dissolved 137Cs concentrations of soil water, groundwater, and rainfall were not detected, while higher dissolved 137Cs concentrations were detected in throughfall than river water. K+ concentrations were higher under storm flow than base flow, and dissolved organic carbon increased toward the peak flow rate. These findings suggested that one main factor influencing generation of dissolved 137Cs in the river water was leaching from organic material in flooded areas. However, further investigation is needed to clarify the dominant source of dissolved 137Cs in river water.
Large‐eddy simulation of subtropical cloud‐topped boundary layers: 1. A forcing framework with closed surface energy balance
Authors: Tan Zhihong , Schneider Tapio , Teixeira João , Pressel Kyle G. 
Published: September 2016

AbstractLarge‐eddy simulation (LES) of clouds has the potential to resolve a central question in climate dynamics, namely, how subtropical marine boundary layer (MBL) clouds respond to global warming. However, large‐scale processes need to be prescribed or represented parameterically in the limited‐area LES domains. It is important that the representation of large‐scale processes satisfies constraints such as a closed energy balance in a manner that is realizable under climate change. For example, LES with fixed sea surface temperatures usually do not close the surface energy balance, potentially leading to spurious surface fluxes and cloud responses to climate change. Here a framework of forcing LES of subtropical MBL clouds is presented that enforces a closed surface energy balance by coupling atmospheric LES to an ocean mixed layer with a sea surface temperature (SST) that depends on radiative fluxes and sensible and latent heat fluxes at the surface. A variety of subtropical MBL cloud regimes (stratocumulus, cumulus, and stratocumulus over cumulus) are simulated successfully within this framework. However, unlike in conventional frameworks with fixed SST, feedbacks between cloud cover and SST arise, which can lead to sudden transitions between cloud regimes (e.g., stratocumulus to cumulus) as forcing parameters are varied. The simulations validate this framework for studies of MBL clouds and establish its usefulness for studies of how the clouds respond to climate change.
Moisture‐radiative cooling instability
Authors: Beucler Tom , Cronin Timothy W. 
Published: September 2016

AbstractRadiative‐convective equilibrium (RCE)—the statistical equilibrium state of the atmosphere where convection and radiation interact in the absence of lateral transport—is widely used as a basic‐state model of the tropical atmosphere. The possibility that RCE may be unstable to development of large‐scale circulation has been raised by recent modeling, theoretical, and observational studies, and could have profound consequences for our understanding of tropical meteorology and climate. Here, we study the interaction between moisture and radiative cooling as a contributor to instability of RCE. We focus on whether the total atmospheric radiative cooling decreases with column water vapor; this condition, which we call moisture‐radiative cooling instability (MRCI), provides the potential for unstable growth of moist or dry perturbations. Analytic solutions to the gray‐gas radiative transfer equations show that MRCI is satisfied when the total column optical depth—linked to column water vapor—exceeds a critical threshold. Both the threshold and the growth rate of the instability depend strongly on the shape of the water vapor perturbation. Calculations with a realistic radiative transfer model confirm the existence of MRCI for typical tropical values of column water vapor, but show even stronger dependence on the vertical structure of water vapor perturbation. Finally, we analyze the sensitivity of atmospheric radiative cooling to variability in column water vapor in observed tropical soundings. We find that clear‐sky MRCI is satisfied across a range of locations and seasons in the real tropical atmosphere, with a partial growth rate of ∼1 month.
Does Working Memory Mediate the Link Between Dispositional Optimism and Depressive Symptoms?
Authors: Alloway Tracy Packiam , Horton John C. 
Published: September 2016

SummaryThe aim of this study was to explore the interplay between working memory (WM), dispositional optimism, and depressive symptoms in participants across a wide age band (16–79 years) in a nonclinical sample using a computer‐based interface. We administered tests of visuospatial WM (processing and recall), dispositional optimism (optimism and pessimism), and self‐reported depression. There were two main findings: 1) both optimism and pessimism were independent predictors of a self‐rated depression score; 2) WM recall scores predicted both optimism and pessimism. The findings suggest the following pattern: according to the negativity bias, a pessimistic outlook presents as a strong stimulus for attentional allocation, which results in depression. However, a strong WM can counter this pattern, as individuals can allocate attention to the weaker stimulus, which is an optimistic outlook. Copyright © 2016 John Wiley & Sons, Ltd.
Synthesis of Biaryls via Ligand‐Free Suzuki–Miyaura Cross‐Coupling Reactions: A Review of Homogeneous and Heterogeneous Catalytic Developments
Authors: Hussain Ibrar , Capricho Jaworski , Yawer Mirza A. 
Published: September 2016

AbstractThis review describes the recent developments in the field of Suzuki–Miyaura cross‐coupling reaction, in particular with regard to ligand‐free catalysis. The catalysts outlined here allow convenient and green synthetic pathways specifically for the construction of C–C bonds. They enable the synthesis of biaryls by the coupling arylboronic acids with aryl halides. The literature reporting ligand‐free synthesis of biaryls from 2010 to May 2015 has been reviewed.magnified image
Cutaneous B‐cell lymphomas: 2016 update on diagnosis, risk‐stratification, and management
Authors: Wilcox Ryan A. 
Published: September 2016

Disease overviewApproximately one‐fourth of cutaneous lymphomas are B‐cell derived and are generally classified into three distinct subgroups: primary cutaneous follicle center lymphoma (PCFCL), primary cutaneous marginal zone lymphoma (PCMZL), and primary cutaneous diffuse large B‐cell lymphoma, leg type (PCDLBCL, LT).DiagnosisDiagnosis and disease classification is based on histologic review and immunohistochemical staining of an appropriate skin biopsy. Pathologic review and an appropriate staging evaluation are necessary to distinguish primary cutaneous B‐cell lymphomas from systemic B‐cell lymphomas with secondary skin involvement.Risk‐stratificationDisease histology remains the most important prognostic determinant. Both PCFCL and PCMZL are indolent lymphomas that infrequently disseminate to extracutaneous sites and are associated with 5‐year survival rates that exceed 95%. In contrast, PCDLBCL, LT is an aggressive lymphoma with an inferior prognosis.Risk‐adapted therapyPCFCL and PCMZL patients with solitary or relatively few skin lesions may be affectively managed with local radiation therapy. While single‐agent rituximab may be employed for patients with more widespread skin involvement, multiagent chemotherapy is rarely appropriate. In contrast, management of patients with PCDLBCL, LT is comparable to the management of patients with systemic DLBCL. Am. J. Hematol. 91:1052–1055, 2016. © 2016 Wiley Periodicals, Inc.
Synthese cyclischer Polymere durch Ringschluss‐Strategien
Authors: Josse Thomas , De Winter Julien , Gerbaux Pascal , Coulembier Olivier 
Published: September 2016

AbstractDie Synthese cyclischer Makromoleküle war – vor allem bedingt durch die schwierige Verknüpfung der Kettenenden – schon immer eine anspruchsvolle Aufgabe in den Polymerwissenschaften. Beginnend mit den wegweisenden Arbeiten von Jacobson und Stockmayer wurden die Herstellungsmethoden für cyclische Polymere in den vergangenen zwanzig Jahren dank der Einführung kontrollierter Polymerisationsmechanismen und effizienter Kupplungsreaktionen in die organischen Chemie erheblich verbessert. Dieser Aufsatz bietet einen kritischen aktuellen Überblick und veranschaulicht die beträchtlichen Leistungen in den letzten Jahren, mit denen die Verfügbarkeit von Makrocyclen für Untersuchungen in Industrie und Forschung durch Ringschlussmethoden verbessert wurde. Einen Schwerpunkt bilden dabei die Herstellungsmethoden für Monocyclen, aus denen normalerweise wiederum kompliziertere Strukturen erhalten werden.
Asymmetrische Organokatalyse: α,β‐ungesättigte Acylammoniumsalze erweisen sich als immer nützlicher
Authors: Vellalath Sreekumar , Romo Daniel 
Published: September 2016

AbstractWährend Acylammoniumsalze gut untersucht sind, fanden chirale α,β‐ungesättigte Acylammoniumsalze deutlich weniger Beachtung. Zwar sind diese Intermediate geeignete Synthone, die ausgehend von gängigen ungesättigten Säuren und Säurechloriden leicht zugänglich sind und drei reaktive Zentren aufweisen, doch ist ihre Anwendung in der organischen Synthese wegen des Fehlens geeigneter chiraler Lewis‐Basen für ihre Herstellung eingeschränkt. In den vergangenen Jahren wurden neue Einsatzmöglichkeiten für chirale ungesättigte Acylammoniumsalzen entwickelt und somit die einzigartige Reaktivität dieser Intermediate aufgezeigt, was zur Entwicklung eines breitgefächerten Spektrums an katalytischen asymmetrischen Reaktionen, darunter auch Organokaskadenprozesse, führte. Dieser Kurzaufsatz beleuchtet das aktuelle und wachsende Interesse an diesen Intermediaten, das eine weitere Erforschung ihres ungenutzten Potenzials zur asymmetrischen Organokaskaden‐Katalyse auslösen könnte. Ein kursorischer Vergleich wird zu verwandten ungesättigten Iminium‐ und Acylazolium‐Intermediaten gezogen.
Triphenylboran‐katalysierte chemoselektive Reduktion von tertiären Amiden zu Aminen
Authors: Mukherjee Debabrata , Shirase Satoru , Mashima Kazushi , Okuda Jun 
Published: September 2016

AbstractTriphenylboran (BPh3) katalysierte die Reduktion tertiärer Amide mit Hydrosilanen zu Aminen unter milden Bedingungen in Gegenwart von Ketonen, Estern und Iminen bei hoher Chemoselektivität. N,N‐Dimethylacrylamid wurde unter Bildung des α‐Silylamids reduziert. Erste Studien zeigen, dass sich die Hydrosilylierung mit dem Katalysator BPh3 mechanistisch gegenüber der Hydrosilylierung mit dem stärker elektrophilen B(C6F5)3 unterscheidet.
A Convenient Late‐Stage Fluorination of Pyridylic C−H Bonds with N‐Fluorobenzenesulfonimide
Authors: Meanwell Michael , Nodwell Matthew B. , Martin Rainer E. , Britton Robert 
Published: September 2016

AbstractPyridine features prominently in pharmaceuticals and drug leads, and methods to selectively manipulate pyridine basicity or metabolic stability are highly sought after. A robust, metal‐free direct fluorination of unactivated pyridylic C−H bonds was developed. This convenient reaction shows high functional‐group tolerance and offers complimentary selectivity to existing C−H fluorination strategies. Importantly, this late‐stage pyridylic C−H fluorination provides opportunities to rationally modulate the basicity, lipophilicity, and metabolic stability of alkylpyridine drugs.
Biomimetic Nanofluidic Diode Composed of Dual Amphoteric Channels Maintains Rectification Direction over a Wide pH Range
Authors: Sui Xin , Zhang Zhen , Zhang Zhenyu , Wang Zhiwei , Li Chao , Yuan Hao , Gao Longcheng , Wen Liping , Fan Xia , Yang Lijun , Zhang Xinru , Jiang Lei 
Published: September 2016

AbstractpH‐gated ion channels in cell membranes play important roles in the cell's physiological activities. Many artificial nanochannels have been fabricated to mimic the natural phenomenon of pH‐gated ion transport. However, these nanochannels show pH sensitivity only within certain pH ranges. Wide‐range pH sensitivity has not yet been achieved. Herein, for the first time, we provide a versatile strategy to increase the pH‐sensitive range by using dual amphoteric nanochannels. In particular, amphoteric polymeric nanochannels with carboxyl groups derived from a block copolymer (BCP) precursor and nanochannels with hydroxyl groups made from anodic alumina oxide (AAO) were used. Due to a synergistic effect, the hybrid nanochannels exhibit nanofluidic diode properties with single rectification direction over a wide pH range. The novel strategy presented here is a scalable, low‐cost, and robust alternative for the construction of large‐area membranes for nanofluidic applications, such as the separation of biomolecules.
Ultra‐Fast Degradation of Chemical Warfare Agents Using MOF–Nanofiber Kebabs
Authors: Zhao Junjie , Lee Dennis T. , Yaga Robert W. , Hall Morgan G. , Barton Heather F. , Woodward Ian R. , Oldham Christopher J. , Walls Howard J. , Peterson Gregory W. , Parsons Gregory N. 
Published: September 2016

AbstractThe threat associated with chemical warfare agents (CWAs) motivates the development of new materials to provide enhanced protection with a reduced burden. Metal–organic frame‐works (MOFs) have recently been shown as highly effective catalysts for detoxifying CWAs, but challenges still remain for integrating MOFs into functional filter media and/or protective garments. Herein, we report a series of MOF–nanofiber kebab structures for fast degradation of CWAs. We found TiO2 coatings deposited via atomic layer deposition (ALD) onto polyamide‐6 nanofibers enable the formation of conformal Zr‐based MOF thin films including UiO‐66, UiO‐66‐NH2, and UiO‐67. Cross‐sectional TEM images show that these MOF crystals nucleate and grow directly on and around the nanofibers, with strong attachment to the substrates. These MOF‐functionalized nanofibers exhibit excellent reactivity for detoxifying CWAs. The half‐lives of a CWA simulant compound and nerve agent soman (GD) are as short as 7.3 min and 2.3 min, respectively. These results therefore provide the earliest report of MOF–nanofiber textile composites capable of ultra‐fast degradation of CWAs.
Poly(iminoborane): Eine schwer fassbare Klasse von anorganischen Hauptgruppenpolymeren?
Authors: Ayhan Ozan , Eckert Thomas , Plamper Felix A. , Helten Holger 
Published: September 2016

AbstractDer hohe Stellenwert anorganischer Hauptgruppenpolymere spiegelt sich wohl am deutlichsten in der wirtschaftlichen Bedeutung von Polysiloxanen (Siliconen) wider. Bororganische Materialien wie π‐konjugierte Organoboranpolymere oder BN‐dotierte polycyclische aromatische Kohlenwasserstoffe erregen derzeit große Aufmerksamkeit. Daher ist es verwunderlich, dass Poly(iminoborane) (PIBs), [BRNR′]n, die Stammverbindungen ungesättigter B‐N‐Polymere, die formal mit Polyacetylen isoelektronisch sind, bis heute noch nicht eindeutig charakterisiert worden waren. Hier stellen wir die Synthese und umfassende Charakterisierung eines linearen Oligo(iminoborans) vor, das aus einer Kette von durchschnittlich 12–14 BN‐Einheiten besteht. Durch unseren Syntheseansatz werden unerwünschte Nebenreaktionen, in denen Borazine gebildet werden, effektiv unterbunden. Unterstützende DFT‐ und TD‐DFT‐Rechnungen verschaffen einen tieferen Einblick in die Mikrostruktur und die elektronische Struktur des Oligomers.
Cyclic Polymers by Ring‐Closure Strategies
Authors: Josse Thomas , De Winter Julien , Gerbaux Pascal , Coulembier Olivier 
Published: September 2016

AbstractThe preparation of cyclic macromolecules has always represented a challenging task for polymer science, mainly because of difficulties in connecting chain extremities together. Initiated by the pioneering studies of Jacobson and Stockmayer, preparative pathways to cyclic polymers have been considerably improved within the last two decades thanks to the advent of both controlled polymerizations and efficient coupling reactions in organic chemistry. This Review aims to provide a critical up‐to‐date overview and illustrate the considerable efforts that have been made in the past few years to improve the availability of macrocycles for industrial and academic investigations through the use of the ring‐closure approach. Particular attention is paid to methods for the preparation of monocycles over more complex architectures, since the latter are usually derived from the former.
Sterically Congested 2,6‐Disubstituted Anilines from Direct C−N Bond Formation at an Iodine(III) Center
Authors: Lucchetti Nicola , Scalone Michelangelo , Fantasia Serena , Muñiz Kilian 
Published: September 2016

Abstract2,6‐Disubstituted anilines are readily prepared from the direct reaction between amides and diaryliodonium salts. As demonstrated for 24 different examples, the reaction is of unusually broad scope with respect to the sterically congested arene and the nitrogen source, occurs without the requirement for any additional promoter, and proceeds through a direct reductive elimination at the iodine(III) center. The efficiency of the coupling procedure is further demonstrated within the short synthesis of a chemerin binding inhibitor.
Homogenous Boron‐doping in Self‐sensitized Carbon Nitride for Enhanced Visible‐light Photocatalytic Activity
Authors: Gu Quan , Liu Jianni , Gao Ziwei , Xue Can 
Published: September 2016

AbstractWe report a solvothermal approach for the preparation of homogeneously B‐doped self‐sensitized carbon nitride (B‐SSCN) composed of a core of B‐doped carbon nitride microspheres and a covalently linked shell of s‐triazine oligomers. Compared to the undoped structure, the obtained B‐SSCN photocatalyst exhibits an enhanced visible‐light activity, excellent stability for photocatalytic hydrogen generation due to a reduced band‐gap, enhanced charge‐separation efficiency, and better surface reactivity of B‐SSCN. This work provides a new strategy to uniformly insert heteroatoms into the polymeric carbon nitride framework for the development of metal‐free photocatalysts towards efficient production of solar fuels.
Output Feedback Control of Surge and Rotating Stall in Axial Compressors
Authors: Sheng Hanlin , Huang Wei , Zhang Tianhong 
Published: September 2016

AbstractActive control has been widely studied to expand the stable operating range of axial flow compressors in aero‐engines.In this paper, a nonlinear active state feedback controller is proposed first based on bifurcation analysis results of MG model.Then by taking pressure ratio as output parameter, a state observer is designed to estimate the compressor's flow coefficient. An output feedback controller is thus established by combining the observer with the state feedback controller.Finally, digital simulation shows that the proposed output feedback controller not only eliminates the hysteresis loop associated with rotating stall and emergence of surge, but also extends the stable operating range of axial flow compressors effectively.Furthermore, being flexible in using pressure transducer and throttle valve as sensor and actuator respectively, which have been equipped in common engines, the proposed controller has good applicability.
Carbamodithioate‐based fluorescent chemosensor for Hg(II): a staged response approach and investigation into the sensing mechanism
Authors: Cheng Xiaohong , Zhong Zhicheng , Ye Tingting , Zhang Bingjie 
Published: September 2016

AbstractCarbamodithioate‐based compound C1 was designed and synthesized as a new fluorescent probe for Hg2+ ions. Upon the addition of Hg2+ ions, it displayed a rare staged response: the emission spectra of C1 first showed an apparent red‐shift, followed by a dramatic decrease. To investigate the sensing mechanism, control compounds C2 with the same phenanthroimidazole unit and C3 with the same carbamodithioate functionality were synthesized. On comparison, the first step sensing process was ascribed to decreasing photoinduced electron transfer on the coordination of Hg2+ with the lone pair electrons of the nitrogen atom on the phenanthroimidazole ring. The affinity of Hg2+ and the carbamodithioate unit with four sulfur atoms then induced changes in intramolecular charge transfer efficiency and the second step fluorescent response.