bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observation and modeling of gravity wave propagation through reflection and critical layers above Andes Lidar Observatory at Cerro Pachón, Chile
Authors: Cao Bing , Heale Christopher J. , Guo Yafang , Liu Alan Z. , Snively Jonathan B. 
Published: October 2016

AbstractA complex gravity wave event was observed from 04:30 to 08:10 UTC on 16 January 2015 by a narrow‐band sodium lidar and an all‐sky airglow imager located at Andes Lidar Observatory (ALO) in Cerro Pachón (30.25°S, 70.73°W), Chile. The gravity wave packet had a period of 18–35 min and a horizontal wavelength of about 40–50 km. Strong enhancements of the vertical wind perturbation, exceeding 10 m s−1, were found at ∼90 km and ∼103 km, consistent with nearly evanescent wave behavior near a reflection layer. A reduction in vertical wavelength was found as the phase speed approached the background wind speed near ∼93 km. A distinct three‐layered structure was observed in the lidar data due to refraction of the wave packet. A fully nonlinear model was used to simulate this event, which successfully reproduced the amplitudes and layered structure seen in observations. The model results provide dynamical insight, suggesting that a double reflection occurring at two separate heights caused the large vertical wind amplitudes, while the three‐layered structure in the temperature perturbation was a result of relatively stable regions at those altitudes. The event provides a clear perspective on the filtering processes to which short‐period, small‐scale gravity waves are subject in mesosphere and lower thermosphere.
An automated satellite cloud classification scheme using self‐organizing maps: Alternative ISCCP weather states
Authors: McDonald Adrian J. , Cassano John J. , Jolly Ben , Parsons Simon , Schuddeboom Alex 
Published: October 2016

AbstractThis study explores the application of the self‐organizing map (SOM) methodology to cloud classification. In particular, the SOM is applied to the joint frequency distribution of the cloud top pressure and optical depth from the International Satellite Cloud Climatology Project (ISCCP) D1 data set. We demonstrate that this scheme produces clusters which have geographical and seasonal patterns similar to those produced in previous studies using the k‐means clustering technique but potentially provides complementary information. For example, this study identifies a wider range of clusters representative of low cloud cover states with distinct geographic patterns. We also demonstrate that two rather similar clusters, which might be considered the same cloud regime in other classifications, are distinct based on the seasonal variation of their geographic distributions and their cloud radiative effect in the shortwave. Examination of the transitions between regimes at particular geographic positions between one day and the next also shows that the SOM produces an objective organization of the various cloud regimes that can aid in their interpretation. This is also supported by examination of the SOM's Sammon map and correlations between neighboring nodes geographic distributions. Ancillary ERA‐Interim reanalysis output also allows us to demonstrate that the clusters, identified based on the joint histograms, are related to an ordered continuum of vertical velocity profiles and two‐dimensional vertical velocity versus lower tropospheric stability histograms which have a clear structure within the SOM. The different nodes can also be separated by their longwave and shortwave cloud radiative effect at the top of the atmosphere.
Rhodium‐Catalyzed Regioselective Synthesis of Isoindolium Salts from 2‐Arylpyridines and Alkenes in Aqueous Medium under Oxygen
Authors: Upadhyay Nitinkumar Satyadev , Jayakumar Jayachandran , Cheng Chien‐Hong 
Published: October 2016

AbstractA highly regioselective synthesis of pyrido[2,1‐a]isoindolium salts from 2‐arylpyridines and two equivalents of electron‐deficient alkenes catalyzed by rhodium is demonstrated. The reaction was carried out in aqueous medium at 110 °C using inexpensive oxygen as oxidant. Reverse aza‐Michael addition of the isoindolium salt occurs when the salt was treated with base to give a β‐disubstituted alkene product. A reaction mechanism involving an ortho C–H olefination of 2‐arylpyridine by alkene, intramolecular aza‐Michael addition, deprotonation at the β‐carbon of the alkene fragment followed by another Michael addition to give the final product is proposed.magnified image
Effects of psychosocial work factors and psychological distress on self‐assessed work ability: A 7‐year follow‐up in a general working population
Authors: Leijon Ola , Balliu Natalja , Lundin Andreas , Vaez Marjan , Kjellberg Katarina , Hemmingsson Tomas 
Published: October 2016

BackgroundToinvestigate the effects of psychosocial work factors (PWF) and psychological distress (PD) on self‐assessed work ability.MethodsThis follow‐up study included 7,810 individuals (55%women) with good work ability at baseline. PWFandPD (measured by GHQ‐12) were assessed at baseline and work ability at 7‐year follow‐up. Effects of PWF and PD on work ability were analyzed by logistic regression, odds ratios (OR) with 95% CI, and by mediation analysisusing 4‐way decomposition.ResultsLow support was associated with poor work ability for both women and men (OR 1.78 and 1.89). For men, also low skill discretion was associated with poor work ability (OR 2.07). For both women and men, PD was associated with poor work ability (OR 3.41 and 1.84). PD did not act as an intermediate variablein the association between PWF and work ability.ConclusionStrategies for sustainable work ability should focus on both working conditions and health factors. Am. J. Ind. Med. 60:121–130, 2017. © 2016 Wiley Periodicals, Inc.
Role of Fibulin 3 in Aging‐Related Joint Changes and Osteoarthritis Pathogenesis in Human and Mouse Knee Cartilage
Authors: Hasegawa Akihiko , Yonezawa Tomo , Taniguchi Noboru , Otabe Koji , Akasaki Yukio , Matsukawa Tetsuya , Saito Masahiko , Neo Masashi , Marmorstein Lihua Y. , Lotz Martin K. 
Published: October 2016

ObjectiveThe EFEMP1 gene encoding fibulin 3 is specifically expressed in the superficial zone (SZ) of articular cartilage. The aims of this study were to examine the expression patterns of fibulin 3 in the knee joints during aging and during osteoarthritis (OA) and to determine the role of fibulin 3 in the pathogenesis of OA.MethodsImmunohistochemical analysis was performed on normal and OA knee cartilage samples from humans and mice. Experimental OA was induced in wild‐type and fibulin 3−/− mice, and the severity of OA was evaluated by histologic scoring. To examine fibulin 3 function, human chondrocyte monolayer cultures were transfected with small interfering RNA (siRNA), followed by quantitative polymerase chain reaction and Western blot analyses. Human bone marrow–derived mesenchymal stem cells (BM‐MSCs) were transduced with an EFEMP1 lentivirus and analyzed for markers of chondrogenesis.ResultsFibulin 3 was specifically expressed in the SZ of normal knee joint cartilage from humans and mice, and the expression levels declined with aging. Both aging‐related OA and experimental OA were significantly more severe in fibulin 3−/− mice compared with wild‐type mice. Fibulin 3 expression was high in undifferentiated human BM‐MSCs and decreased during chondrogenesis. Suppression of fibulin 3 by siRNA significantly increased the expression of SOX9, type II collagen, and aggrecan in human articular chondrocytes, while overexpression of fibulin 3 inhibited chondrogenesis in BM‐MSCs.ConclusionFibulin 3 is specifically expressed in the SZ of articular cartilage and its expression is reduced in aging and OA. Fibulin 3 regulates differentiation of adult progenitor cells, and its aging‐related decline is an early event in the pathogenesis of OA. Preventing aging‐associated loss of fibulin 3 or restoring it to normal levels in SZ chondrocytes has the potential to delay or prevent the onset of OA.
Synthesis of Functional Bis(pentafluoroethyl)silanes (C2F5)2SiX2, with X=H, F, Cl, Br, OPh, and O2CCF3
Authors: Schwarze Nico , Kurscheid Boris , Steinhauer Simon , Neumann Beate , Stammler Hans‐Georg , Ignat'ev Nikolai , Hoge Berthold 
Published: October 2016

AbstractAs recently shown, the introduction of pentafluoroethyl functionalities into silicon compounds is of general interest due to an enhanced Lewis acidity of the resulting species. By this means, the synthesis of previously inaccessible hypervalent silicon derivatives is enabled. While an easy access to tris(pentafluoroethyl)silanes has already been published, synthetic strategies for the selective preparation of bis derivatives are yet unknown. In this contribution, a convenient protocol for the synthesis of functional bis(pentafluoroethyl)silicon compounds is presented. These compounds represent precursors for the synthesis of pentafluoroethylated polysiloxanes. Furthermore, they prove to be resistant to oxonium cations, which is a key feature for the preparation of stable pentafluoroethylsilic acids. Treatment of dichlorodiphenoxysilane with in situ generated pentafluoroethyl lithium leads to the corresponding bis(pentafluoroethyl)silane in high yields. (C2F5)2Si(OPh)2 serves as a starting material for further functionalized bis(pentafluoroethyl)silanes. These silanes have been isolated and their reactivity towards N bases studied. The pronounced Lewis acidity of the obtained compounds has been documented by the formation of octahedral adducts with nitrogen donors such as 1,10‐phenanthroline and acetonitrile.
Two Independent Orthogonal Stereomutations at a Single Asymmetric Center: A Narcissistic Couple
Authors: Gillick‐Healy Malachi W. , Jennings Elizabeth V. , Müller‐Bunz Helge , Ortin Yannick , Nikitin Kirill , Gilheany Declan G. 
Published: October 2016

AbstractThe energy barriers in our recently discovered Walden‐type inversion of chlorophosphonium salts are similar to those for Cope rearrangements of caged cyclic hydrocarbons. Therefore, we have designed a molecular system that integrates the two processes, thereby producing the first embodiment of a chemical species that can undergo two entirely different and independent stereomutation mechanisms at the same nominal asymmetric center. Thus, the energy barrier to the rearrangement of 9‐phenyl‐9‐phosphabarbaralane oxide, which is easily prepared by a new high‐yielding synthesis, was found to be roughly 11 kcal mol−1. This value is in contrast to the parent barbaralane (7.3 kcal mol−1) but in good agreement with our computational results for the rearrangement barriers. Crucially, in the corresponding chlorophosphonium derivative, two stereomutations occur simultaneously: a fast Cope rearrangement (barrier ≈12 kcal mol−1) and a slow Walden‐type inversion of the phosphorus center (barrier ≈21 kcal mol−1). The computational model also revealed a relationship between the Cope rearrangement barrier and the bridgehead distance. The phenomenon of two independent and geometrically orthogonal stereomutations at a single asymmetric center provided important general insights into reaction pathway bifurcation, microscopic reversibility, and dynamic stereochemistry. This first example of coexisting alternative mechanisms that involve covalent bonds may encourage the design of new types of dynamic molecular structures.
Coinage Metal Complexes of Bis‐Alkynyl‐Functionalized N‐Heterocyclic Carbenes: Reactivity, Photophysical Properties, and Quantum Chemical Investigations
Authors: Kiefer Claude , Bestgen Sebastian , Gamer Michael T. , Kühn Michael , Lebedkin Sergei , Weigend Florian , Kappes Manfred M. , Roesky Peter W. 
Published: October 2016

AbstractBis‐phenylpropynyl‐functionalized imidazolium salts and their corresponding gold and copper N‐heterocyclic carbene (NHC) complexes were prepared in order to investigate their potential application for the synthesis of heterometallic coinage metal compounds. By transmetalation reactions with different precious metal sources, including copper and silver phenylacetylides [MCCPh]n (M=Cu, Ag), polynuclear compounds were obtained, which were further investigated for their photoluminescence properties. Additionally, one gold NHC complex was post‐functionalized by autocatalytic hydration of the alkynyl side chains. Time‐dependent DFT investigations of singlet electronic excitations in representative complexes revealed excited states of diverse character, as determined by the specific complex structure and metallophilic interactions.
N‐Methyl‐Benzothiazolium Salts as Carbon Lewis Acids for Si−H σ‐Bond Activation and Catalytic (De)hydrosilylation
Authors: Fasano Valerio , Radcliffe James E. , Curless Liam D. , Ingleson Michael J. 
Published: October 2016

AbstractN−Me‐Benzothiazolium salts are introduced as a new family of Lewis acids able to activate Si−H σ bonds. These carbon‐centred Lewis acids were demonstrated to have comparable Lewis acidity towards hydride as found for the triarylboranes widely used in Si−H σ‐bond activation. However, they display low Lewis acidity towards hard Lewis bases such as Et3PO and H2O in contrast to triarylboranes. The N−Me‐benzothiazolium salts are effective catalysts for a range of hydrosilylation and dehydrosilylation reactions. Judicious selection of the C2 aryl substituent in these cations enables tuning of the steric and electronic environment around the electrophilic centre to generate more active catalysts. Finally, related benzoxazolium and benzimidazolium salts were found also to be active for Si−H bond activation and as catalysts for the hydrosilylation of imines.
A Controlled Route to a Luminescent 3 d10–5 d10 Sulfido Cluster Containing Unique AuCu2(μ3‐S) Motifs
Authors: Polgar Alexander M. , Khadka Chhatra B. , Azizpoor Fard Mahmood , Nikkel Brian , O'Donnell Terrence , Neumann Tobias , Lahring Kiana , Thompson Kyle , Cadogan Carolyn , Weigend Florian , Corrigan John F. 
Published: October 2016

AbstractThe first examples of gold(I) trimethylsilylchalcogenolate complexes were synthesized and their reactivity showcased in the preparation of a novel gold–copper–sulfur cluster [Au4Cu4S4(dppm)2] (dppm=bis(diphenylphosphino)methane). The unprecedented structural chemistry of this compound gives rise to interesting optoelectronic properties, including long‐lived orange luminescence in the solid state. Through time‐dependent density functional theory calculations, this emission is shown to originate from ligand‐to‐metal charge transfer facilitated by Au⋅⋅⋅Cu metallophilic bonding.
Removal of Cr (VI) from aqueous solutions by titanate nanomaterials synthesized via hydrothermal method
Authors: Fan Gongduan , Lin Rujing , Su Zhaoyue , Lin Xiuyong , Xu Renxing , Chen Wei 
Published: October 2016

AbstractTitanate nanomaterials (TNs) were synthesized via a simple hydrothermal method. The physical‐chemical properties of the as‐prepared TNs, such as morphology, structure, surface area, and chemical composition, were characterized by XRD, SEM, and BET. The absorption capability and adsorptive mechanism of Cr (VI) in aqueous solutions were tested in the static system. The results showed that the TNs prepared with reaction time of 24 h were in pure monoclinic phase which aggregated mutually to form a unique layered structure. TNs were considered excellent adsorbents to Cr (VI). When pH = 1, the adsorption capacity was up to 83.91 mg/g. The adsorption kinetics of Cr (VI) followed the pseudo‐first order model. The equilibrium adsorption time of TNs was 80 min. The Langmuir isotherm model fitted the equilibrium data best. The adsorption of Cr (VI) onto TNs was an exothermic process, and the adsorption process was mainly composed of electrostatic attraction. The structure of TNs basically remained unchanged after adsorption.
Initiation of and adherence to tamoxifen and aromatase inhibitor therapy among elderly women with ductal carcinoma in situ
Authors: Zhao Hui , Hei Nainan , Wu Yiling , Chan Winston , Lei Xiudong , Cameron Carrie , Chang Shine , Chavez‐MacGregor Mariana , Giordano Sharon H. 
Published: October 2016

BACKGROUNDThe National Surgical Adjuvant Breast and Bowel Project B35 and International Breast Cancer Intervention Studies II Ductal Carcinoma In Situ trials showed similar treatment effects of anastrozole and tamoxifen in reducing cancer recurrence risk among ductal carcinoma in situ (DCIS) patients. Studies have shown low levels of hormone therapy drug initiation for DCIS patients, but the current body of literature lacks information on the 5‐year adherence rates for these drugs from population‐based studies.METHODSThis study evaluated the initiation and 5‐year adherence levels for women aged 66 to 85 years who had been diagnosed with estrogen receptor (ER)–positive DCIS between 2007 and 2011 according to the Surveillance, Epidemiology, and End Results and Texas Cancer Registry databases linked to Medicare claims. Chi‐square tests, trend tests, and logistic regression were used to identify factors associated with treatment initiation.RESULTSThere were 2871 women with ER‐positive DCIS, and approximately 45% began treatment with tamoxifen or aromatase inhibitors (AIs) within 1 year of their DCIS diagnosis. The median age was 73 years for the users and 75 years for the nonusers. Women aged 66 to 70 years who underwent lumpectomy and radiation therapy were significantly more likely to initiate hormone therapy. The initiation of therapy was also significantly associated with patients' geographic location, education, marital status, diagnosis year, and race/ethnicity. Among users, adherence decreased from 67% in the first year to 30% in the fifth year.CONCLUSIONSInitiation and adherence levels for tamoxifen or AIs among older women with ER‐positive DCIS are low. Future studies should develop methods to ensure that informed discussions take place between health care providers and patients regarding hormonal therapy for cancer prevention. Cancer 2017;123:940–47. © 2016 American Cancer Society.
A practical construction for large universe hierarchical attribute‐based encryption
Authors: Li Cong , Fang Yuejian , Zhang Xing , Jin Cancan , Shen Qingni , Wu Zhonghai 
Published: October 2016

SummaryWe present a practical large universe hierarchical attribute‐based encryption (LU‐HABE) scheme, which supports monotone access structures. In our system, key generation centers (KGCs), any one in which is labeled by a unique identity, are organized as a hierarchical structure. Thus, all secret keys issued by the KGC contain 2 parts: the identity‐related one and the attribute‐related one. Once the data owner wants to encrypt his/her data, he/she needs to specify certain numbers of pairs according to his/her demand. The pair consists of an identity of a KGC and a policy of attributes managed by the corresponding KGC, eg, IDi and (Mi, ρi). If and only if an identity associated with user's secret key is equal to or is an ancestor of one of the identities appearing in ciphertext, and simultaneously a set of attributes belonging to the user satisfies the policy, the user can decrypt it successfully. Our scheme is proved to be selectively secure in the standard model under the modified “q‐type” assumption similar to the ones used in former works and is extended to support online/offline encryption. To show the efficiency of our construction, we implement our original scheme and the extended one in Charm. Analyses show that both of them are very practical.
Application of Nanocrystalline Graphite‐like Pyrolytic Carbon Film Electrode in the Electroanalytical Determination of Famotidine
Authors: Hadi Mojtaba , Ehsani Ali , Honarmand Ebrahim 
Published: October 2016

AbstractDirect electro‐oxidation of famotidine at different graphitic carbon‐based electrode materials was evaluated. These materials included conventional electrodes of edge‐plane pyrolytic graphite, basal‐plane pyrolytic graphite, carbon paste, and glassy carbon as well as nano‐structured carbon‐based materials such as pyrolytic carbon film, carbon nanotube, and nano‐graphene. Raman spectroscopy and scanning electron microscopy were employed to analyze their structural and morphological features. It was found that the pyrolytic carbon film electrode, after a simple and fast anodic activation, shows superior electroanalytical performance. The method was successfully applied for the electroanalytical determination of famotidine in tablet dosage forms and urine samples.
Benthic injury dose–response models for polychlorinated biphenyl–contaminated sediment using equilibrium partitioning
Authors: Finkelstein Kenneth , Beckvar Nancy , Dillon Tom 
Published: October 2016

Abstract

The study goal was to develop a sediment polychlorinated biphenyl (PCB) dose–response model based on benthic invertebrate effects to PCBs. The authors used an equilibrium partitioning (EqP) approach to generate predicted PCB sediment effect concentrations (largely Aroclor 1254) associated with a gradient of toxic effects in benthic organisms from effects observed in aquatic toxicity studies. The present study differs from all other EqP collective sediment investigations in that the authors examined a common dose–response gradient of effects for PCBs rather than a single, protective value. The authors reviewed the chronic aquatic toxicity literature to identify measured aqueous PCB concentrations and associated benthic invertebrate effects. The authors control-normalized the aquatic toxic effect data and expressed results from various studies as a common metric, percent injury. Then, they calculated organic carbon–normalized sediment PCB concentrations (mg/kg organic carbon) from the aqueous PCB toxicity data set using EqP theory based on the US Environmental Protection Agency's (EPIWEB 4.1) derivation of the water–organic carbon partition coefficient (KOC). Lastly, the authors constructed a nonlinear dose–response numerical model for these synoptic sediment PCB concentrations and biological effects: Y = 100/1 + 10([logEC50–logX] × [Hill slope]) (EC50 = median effective concentration). These models were used to generate “look-up” tables reporting percent injury in benthic biota for a range of Aroclor-specific sediment concentrations. For example, the model using the EPIWEB KOC estimate predicts mean benthic injury of 23.3%, 46.0%, 70.6%, 87.1%, and 95% for hypothetical sediment concentrations of 1 mg/kg, 2 mg/kg, 4 mg/kg, 8 mg/kg, and 16 mg/kg dry weight of Aroclor 1254, respectively (at 1% organic carbon). The authors recommend the model presented for screening but suggest, when possible, determining a site-specific KOC that, along with the tables and equations, allows users to create their own protective dose–response sediment concentration. Environ Toxicol Chem 2017;36:1311–1329. © 2016 SETAC