bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three‐Stage Inter‐Orthorhombic Evolution and High Thermoelectric Performance in Ag‐Doped Nanolaminar SnSe Polycrystals
Authors: Zhang Lijuan , Wang Jianli , Sun Qiao , Qin Peng , Cheng Zhenxiang , Ge Zhenhua , Li Zhen , Dou Shixue 
Published: June 2017

AbstractThe ultrahigh thermoelectric performance of SnSe‐based single crystals has attracted considerable interest in their polycrystalline counterparts. However, the temperature‐dependent structural transition in SnSe‐based thermoelectric materials and its relationship with their thermoelectric performance are not fully investigated and understood. In this work, nanolaminar SnSe polycrystals are prepared and characterized in situ using neutron and synchrotron powder diffraction measurements at various temperatures. Rietveld refinement results indicate that there is a complete inter‐orthorhombic evolution from Pnma to Cmcm by a series of layer slips and stretches along the a‐ and b‐axes over a 200 K temperature range. This phase transition leads to drastic enhancement of the carrier concentration and phonon scattering above 600 K. Moreover, the unique nanolaminar structure effectively enhances the carrier mobility of SnSe. Their grain and layer boundaries further improve the phonon scattering. These favorable factors result in a high ZT of 1.0 at 773 K for pristine SnSe polycrystals. The thermoelectric performances of polycrystalline SnSe are further improved by p‐type and n‐type dopants (i.e., doped with Ag and SnCl2, respectively), and new records of ZT are achieved in Ag0.015Sn0.985Se (ZT of 1.3 at 773 K) and SnSe0.985Cl0.015 (ZT of 1.1 at 773 K) polycrystals.
Cesium Doped NiOx as an Efficient Hole Extraction Layer for Inverted Planar Perovskite Solar Cells
Authors: Chen Wei , Liu Fang‐Zhou , Feng Xi‐Yuan , Djurišić Aleksandra B. , Chan Wai Kin , He Zhu‐Bing 
Published: June 2017

AbstractOrganic–inorganic hybrid perovskite solar cells have resulted in tremendous interest in developing next generation photovoltaics due to high record efficiency exceeding 22%. For inverted structure perovskite solar cells, the hole extraction layers play a significant role in achieving efficient and stable perovskite solar cell by modifying charge extraction, interfacial recombination losses, and band alignment. Here, cesium doped NiOx is selected as a hole extraction layer to study the impact of Cs dopant on the optoelectronic properties of NiOx and the photovoltaic performance. Cs doped NiOx films are prepared by a simple solution‐based method. Both doped and undoped NiOx films are smooth and highly transparent, while the Cs doped NiOx exhibits better electron conductivity and higher work function. Therefore, Cs doping results in a significant improvement in the performance of NiOx‐based inverted planar perovskite solar cells. The best efficiency of Cs doped NiOx devices is 19.35%, and those devices show high stability as well. The improved efficiency in devices with Cs:NiOx is attributed to a significant improvement in the hole extraction and better band alignment compared to undoped NiOx. This work reveals that Cs doped NiOx is very promising hole extraction material for high and stable inverted perovskite solar cells.
Carbon, nitrogen and oxygen isotope fractionation during food cooking: Implications for the interpretation of the fossil human record
Authors: Royer Aurélien , Daux Valérie , Fourel François , Lécuyer Christophe 
Published: June 2017

AbstractObjectivesStable isotope data provide insight into the reconstruction of ancient human diet. However, cooking may alter the original stable isotope compositions of food due to losses and modifications of biochemical and water components.MethodsTo address this issue, carbon, nitrogen and oxygen isotope ratios were measured on meat aliquots sampled from various animals such as pork, beef, duck and chicken, and also from the flesh of fishes such as salmon, European seabass, European pilchard, sole, gilt‐head bream, and tuna. For each specimen, three pieces were cooked according to the three most commonly‐known cooking practices: boiling, frying and roasting on a barbecue.ResultsOur data show that cooking produced isotopic shifts up to 1.8‰, 3.5‰, and 5.2‰ for δ13C, δ15N, and δ18O values, respectively. Such variations between raw and cooked food are much greater than previously estimated in the literature; they are more sensitive to the type of food rather than to the cooking process itself, except in the case of boiling.ConclusionsReconstructions of paleodietary may thus suffer slight bias in cases of populations with undiversified diets that are restrained toward a specific raw or cooked product, or using a specific cooking mode. In cases of oxygen isotope compositions from skeletal remains (bones, teeth), they not only constitute a valuable proxy for reconstructing past climatic conditions, but they could also be used to improve our knowledge of past human diet.
Efficient Synthesis of Polycyclic γ‐Lactams by Catalytic Carbonylation of Ene‐Imines via Nickelacycle Intermediates
Authors: Hoshimoto Yoichi , Ashida Keita , Sasaoka Yukari , Kumar Ravindra , Kamikawa Ken , Verdaguer Xavier , Riera Antoni , Ohashi Masato , Ogoshi Sensuke 
Published: June 2017

AbstractThe nickel(0)‐catalyzed carbonylative cycloaddition of 1,5‐ and 1,6‐ene‐imines with carbon monoxide (CO) is reported. Key to this reaction is the efficient regeneration of the catalytically active nickel(0) species from nickel carbonyl complexes such as [Ni(CO)3L]. A variety of tri‐ and tetracyclic γ‐lactams were thus prepared in excellent yields with 100 % atom efficiency. Preliminary results on asymmetric derivatives promise potential in the synthesis of enantioenriched polycyclic γ‐lactams.
Alkine als alternativer Einstieg in elektrophile und nukleophile Übergangsmetall‐katalysierte Allylierungen
Authors: Haydl Alexander M. , Breit Bernhard , Liang Tao , Krische Michael J. 
Published: June 2017

AbstractEine Reihe von Übergangsmetall‐Katalysatoren ist in der Lage, terminale und interne Alkine intermediär in entsprechende Allylmetall‐Verbindungen zu überführen, die ihrerseits elektrophile oder nukleophile Reaktivitäten aufweisen können. Während klassische Methoden zur Herstellung von Allylmetall‐Spezies oftmals von der Bildung stöchiometrischer Mengen an Nebenprodukten begleitet sind, ermöglicht der Einsatz von Alkinen als Allylmetall‐Vorstufen vollständig atomökonomische katalytische Prozesse, die außerdem mit hohen Enantioselektivitäten ablaufen.
Carbon–Halogen Bond Activation by Selenium‐Based Chalcogen Bonding
Authors: Wonner Patrick , Vogel Lukas , Düser Maximilian , Gomes Luís , Kniep Florian , Mallick Bert , Werz Daniel B. , Huber Stefan M. 
Published: June 2017

AbstractChalcogen bonding is a little explored noncovalent interaction similar to halogen bonding. This manuscript describes the first application of selenium‐based chalcogen bond donors as Lewis acids in organic synthesis. To this end, the solvolysis of benzhydryl bromide served as a halide abstraction benchmark reaction. Chalcogen bond donors based on a bis(benzimidazolium) core provided rate accelerations relative to the background reactivity by a factor of 20–30. Several comparative experiments provide clear indications that the observed activation is due to chalcogen bonding. The performance of the chalcogen bond donors is superior to that of a related brominated halogen bond donor.
Polydiacetylene/Anti‐HBs Complexes for Visible and Fluorescent Detection of Hepatitis B Surface Antigen on a Nitrocellulose Membrane
Authors: Roh Jinkyu , Lee Su Yeon , Park Sangho , Ahn Dong June 
Published: June 2017

AbstractThe immunochromatographic assay (ICA) using a nitrocellulose (NC) membrane offers several advantages. This technique is a rapid and straightforward method in contrast to other immunoassays. Polydiacetylene (PDA) vesicles have unique optical properties, displaying red color and red fluorescence at the same time. In this system, red‐phase PDA vesicles are used as a fluorescent dye as well as a surface for immobilized hepatitis B surface antibody (HBsAb). PDA has a remarkable stability compared with other fluorescent dyes. In this study, the most suitable PDA/HBsAb complexes are introduced for detecting hepatitis B surface antigen (HBsAg). Then, the PDA/HBsAb complexes affixed antibody is attached to NC membrane, which has two lines to confirm detection of HBsAg. The main advantage of this system is that the detection of HBsAg can be observed in both visible and fluorescent images due to the optical properties of polydiacetylene. Detection of HBsAg is observed up to 0.1 ng mL−1 by fluorescent analysis and confirmed by red line on the NC membrane up to 1 ng mL−1 (HBsAg) using the naked eye. Consequently, these results show that PDA/HBsAb complexes were successfully applied to ICA for the diagnosis of hepatitis B.
Mutation of Conserved Residues Increases in Vitro Activity of the Formylglycine‐Generating Enzyme
Authors: Knop Matthias , Lemnaru Roxana , Seebeck Florian P. 
Published: June 2017

AbstractThe formylglycine‐generating enzyme (FGE) recognizes proteins with a specific cysteine‐containing six‐amino‐acid motif and converts this cysteine residue into formylglycine. The resulting aldehyde function provides a unique handle for selective protein labeling. We have identified two mutations in FGE from Thermomonospora curvata that increase this catalytic efficiency more than 40‐fold. The resulting activity and stability, as well as its ease of recombinant production, make this FGE variant a practical reagent for in vitro protein engineering.
Emulation of Bubble‐Induced Turbulence Using Randomly Moving Particles in a Grid Structure
Authors: Haase Katharina , Kück Ulf D. , Thöming Jörg , Kähler Christian J. 
Published: June 2017

AbstractAn approach to generate turbulence with systematically controllable properties and statistically comparable to real bubble‐induced turbulence is evaluated. Particles are arranged in a flexible regular grid and can move freely in the directions perpendicular to the flow direction. The flow induced by different grid configurations is characterized by particle image velocimetry and electrodiffusion measurement. With these techniques, spatially resolved velocity fields and time‐resolved energy spectra are achieved. Homogeneous turbulence with the intensity comparable to regular bubble flow is obtained downstream from the particle grid. The energy spectra of these emulated turbulent flows agree with the energy spectra of real bubble‐induced turbulence. The proposed concept of turbulence generation is suitable for detailed scientific investigations of bubbles in turbulent flows using sophisticated optical measurement techniques.
Development of a Model for Water Scrubbing‐Based Biogas Upgrading and Biomethane Compression
Authors: Ghaib Karim 
Published: June 2017

AbstractBiomethane is an easily storable, renewable energy source that is applicable to the sectors electricity, heat, and transport. It is mostly obtained from biogas by different upgrading technologies. At present, the most common technology is water scrubbing because of its reliability and simplicity. A methodology for designing as well as for evaluating and optimizing water scrubbing plants including biomethane compression is introduced. To demonstrate possible applications of this methodology, a zero‐emission water scrubbing process characterized by under‐pressure regeneration of washing water is modeled and investigated by a sensitivity analysis.
Analysis of Magnetic Anisotropy and the Role of Magnetic Dilution in Triggering Single‐Molecule Magnet (SMM) Behavior in a Family of CoIIYIII Dinuclear Complexes with Easy‐Plane Anisotropy
Authors: Palacios María A. , Nehrkorn Joscha , Suturina Elizaveta A. , Ruiz Eliseo , Gómez‐Coca Silvia , Holldack Karsten , Schnegg Alexander , Krzystek Jurek , Moreno José M. , Colacio Enrique 
Published: June 2017

AbstractThree new closely related CoIIYIII complexes of general formula [Co(μ‐L)(μ‐X)Y(NO3)2] (X−=NO3− 1, benzoate 2, or 9‐anthracenecarboxylato 3) have been prepared with the compartmental ligand N,N′,N′′‐trimethyl‐N,N′′‐bis(2‐hydroxy‐3‐methoxy‐5‐methylbenzyl)diethylenetriamine (H2L). In these complexes, CoII and YIII are triply bridged by two phenoxide groups belonging to the di‐deprotonated ligand (L2−) and one ancillary anion X−. The change of the ancillary bridging group connecting CoII and YIII ions induces small differences in the trigonally distorted CoN3O3 coordination sphere with a concomitant tuning of the magnetic anisotropy and intermolecular interactions. Direct current magnetic, high‐frequency and ‐field EPR (HFEPR), frequency domain Fourier transform THz electron paramagnetic resonance (FD‐FT THz‐EPR) measurements, and ab initio theoretical calculations demonstrate that CoII ions in compounds 1–3 have large and positive D values (≈50 cm−1), which decrease with increasing the distortion of the pseudo‐octahedral CoII coordination sphere. Dynamic ac magnetic susceptibility measurements indicate that compound 1 exhibits field‐induced single‐molecule magnet (SMM) behavior, whereas compounds 2 and 3 only display this behavior when they are magnetically diluted with diamagnetic ZnII (Zn/Co=10:1). In view of this, it is always advisable to use magnetically diluted complexes, in which intermolecular interactions and quantum tunneling of magnetism (QTM) would be at least partly suppressed, so that “hidden single‐ion magnet (SIM)” behavior could emerge. Field‐ and temperature‐dependence of the relaxation times indicate the prevalence of the Raman process in all these complexes above approximately 3 K.
Hydrogen‐Bond Strength of CC and GG Pairs Determined by Steric Repulsion: Electrostatics and Charge Transfer Overruled
Authors: van der Lubbe Stephanie C. C. , Fonseca Guerra Célia 
Published: June 2017

AbstractInvited for the cover of this issue are Stephanie C. C. van der Lubbe and Célia Fonseca Guerra at the Vrije Universiteit Amsterdam and at Leiden University. The image depicts the importance of steric repulsion in hydrogen bonds between two base pairs and has implications in understanding and predicting the hydrogen bonding mechanism. Read the full text of the article at 10.1002/chem.201701821.
A General Cp*CoIII‐Catalyzed Intramolecular C−H Activation Approach for the Efficient Total Syntheses of Aromathecin, Protoberberine, and Tylophora Alkaloids
Authors: Lerchen Andreas , Knecht Tobias , Koy Maximilian , Daniliuc Constantin G. , Glorius Frank 
Published: June 2017

AbstractHerein, we report a Cp*CoIII‐catalyzed C−H activation approach as the key step to create highly valuable isoquinolones and pyridones as building blocks that can readily be applied in the total syntheses of a variety of aromathecin, protoberberine, and tylophora alkaloids. This particular C−H activation/annulation reaction was achieved with several terminal as well as internal alkyne coupling partners delivering a broad scope with excellent functional group tolerance. The synthetic applicability of this protocol reported herein was demonstrated in the total syntheses of two Topo‐I‐Inhibitors and two 8‐oxyprotoberberine cores that can be further elaborated into the tetrahydroprotoberberine and the protoberberine alkaloid core. Moreover these building blocks were also transformed to six different tylophora alkaloids in expedient fashion.
A predictive analysis of the SP120 and 10D7G2 antibodies for human equilibrative nucleoside transporter 1 (hENT1) in pancreatic ductal adenocarcinoma treated with adjuvant gemcitabine
Authors: Kalloger Steve E , Riazy Maziar , Tessier‐Cloutier Basile , Karasinska Joanna M , Gao Dongxia , Peixoto Renata D , Samimi Setareh , Chow Christine , Wong Hui‐Li , Mackey John R , Renouf Daniel J , Schaeffer David F 
Published: June 2017

AbstractExpression of human equilibrative nucleoside transporter 1 (hENT1) in pancreatic ductal adenocarcinoma (PDAC) has been postulated to be a marker of sensitivity to gemcitabine. However, heterogeneity in the studies attempting to quantify hENT1 expression in patients with PDAC treated with gemcitabine has yielded inconclusive results that impede the adoption of hENT1 expression as a predictive biomarker. Tissue microarrays consisting of PDAC specimens from 227 patients acquired between 1987 and 2013 annotated with treatment and outcome information were subjected to staining with two antibodies for hENT1 (10D7G2 and SP120) on a single automated platform and scored by two independent pathologists blinded to treatment and outcome. The resultant scores were subjected to individual predictive disease‐specific survival analysis and to unsupervised hierarchical clustering to generate a multi‐marker classification. Tumour cell staining prevalence using either SP120 or 10D7G2 was predictive of gemcitabine sensitivity (p = 0.02; p = 0.01). When combined, three groups emerged, classified as SP120Low_10D7G2Low, SP120Low_10D7G2High, and SP120High_10D7G2High, in which adjuvant gemcitabine conferred median survival differences of 0.2, 0.8, and 1.5 (p = 0.76, p = 0.06, p = 0.01) years, respectively. These results were largely replicated in multivariable analysis with the P value for the SP120Low_10D7G2High cluster achieving statistical significance (p = 0.03). These data suggest that either antibody for hENT1 can be used to predict gemcitabine sensitivity in resected PDAC. However, using both antibodies adds valuable information that enables the stratification of patients who can expect to have a good, intermediate, and poor response to adjuvant gemcitabine.
Cardiovascular adverse events in the drug‐development program of bupropion for smoking cessation: A systematic retrospective adjudication effort
Authors: Kittle Jessie , Lopes Renato D. , Huang Mingyan , Marquess Marsha L. , Wilson Matthew D. , Ascher John , Krishen Alok , Hasselblad Vic , Kolls Brad J. , Roe Matthew T. , McGuire Darren K. , Russell Stuart D. , Mahaffey Kenneth W. 
Published: June 2017

BackgroundIn 2011, the US Food and Drug Administration requested that GlaxoSmithKline perform retrospective adjudication of cardiovascular (CV) events reported in the bupropion drug‐development trials for smoking cessation.HypothesisRetrospective adjudication of clinical trial data will not increase the identification of adverse events.MethodsWe performed a comprehensive retrospective analysis of adverse events in 19 previously completed controlled US clinical trials of bupropion marketed for the treatment of smoking cessation, yielding 9479 subjects (5290 bupropion, 2927 placebo, 1018 active control [ACT], and 244 treated concurrently with bupropion and ACT). All adverse events were sent to the Duke Clinical Research Institute for adjudication by Clinical Events Classification (CEC) physician reviewers. The primary endpoint was a composite of major adverse CV events: CV death, nonfatal myocardial infarction (MI), and nonfatal stroke.ResultsOverall, 416 nonfatal CV events in 366 subjects, and 22 deaths, were identified and processed for adjudication. Of these, 7 nonfatal MIs (4 bupropion, 3 placebo, 0 ACT), 5 nonfatal strokes (1 bupropion, 3 placebo, 1 ACT), and 9 CV deaths (4 bupropion, 4 placebo, 1 ACT) were confirmed by the CEC Committee. The primary endpoint occurred in 3/4297 (0.07%) subjects in the bupropion group and in 4/2927 (0.14%) subjects in the placebo group (log‐rank P value: 0.613).Conclusions
CV events in bupropion clinical trials for smoking cessation were uncommon, with no observed increase among subjects assigned to bupropion vs placebo. However, this effort was limited by a paucity of quality data.
Disparities in abnormal mammogram follow‐up time for Asian women compared with non‐Hispanic white women and between Asian ethnic groups
Authors: Nguyen Kim H. , Pasick Rena J. , Stewart Susan L. , Kerlikowske Karla , Karliner Leah S. 
Published: June 2017

BACKGROUNDDelays in abnormal mammogram follow‐up contribute to poor outcomes. In the current study, the authors examined differences in abnormal screening mammogram follow‐up between non‐Hispanic white (NHW) and Asian women.METHODSThe authors used a prospective cohort of NHW and Asian women with a Breast Imaging, Reporting and Data System (BI‐RADS) abnormal result of category 0 or 3‐plus in the San Francisco Mammography Registry between 2000 and 2010. Kaplan‐Meier estimation for the median number of days to follow‐up with a diagnostic radiologic test was performed, and the authors compared the percentage of women with follow‐up at 30 days, 60 days, and 90 days and no follow‐up at 1 year for Asian women overall (and Asian ethnic groups) and NHW women. In addition, the authors assessed the relationship between race/ethnicity and time to follow‐up with adjusted Cox proportional hazards models.RESULTSAmong Asian women, Vietnamese and Filipina women had the longest, and Japanese women the shortest, median follow‐up (32 days, 28 days, and 19 days, respectively) compared with NHW women (15 days). The percentage of women receiving follow‐up at 30 days was lower for Asians versus NHWs (57% vs 77%; P<.0001), and these disparities persisted at 60 days and 90 days for all Asian ethnic groups except Japanese. Asian women had a reduced hazard of follow‐up compared with NHW women (adjusted hazard ratio, 0.70; 95% confidence interval, 0.69‐0.72). Asian women also had a higher rate of receiving no follow‐up compared with NHW women (15% vs 10%; P<.001); among Asian ethnic groups, Filipinas were found to have the highest percentage of women with no follow‐up (18.1%).CONCLUSIONSAsian women, particularly Filipina and Vietnamese women, were less likely than NHW women to receive timely follow‐up after an abnormal screening mammogram. Research should disaggregate Asian ethnicity to better understand and address barriers to effective cancer prevention. Cancer 2017;123:3468‐75. © 2017 American Cancer Society.
TiO2 Anatase Solutions for Electron Transporting Layers in Organic Photovoltaic Cells
Authors: El Kass Moustafa , Brohan Luc , Gautier Nicolas , Béchu Solène , David Céline , Lemaitre Noëlla , Berson Solenn , Richard‐Plouet Mireille 
Published: June 2017

AbstractReflux of a solution of [Ti8O12(H2O)24]Cl8⋅HCl⋅7 H2O as titanium precursor at 120 °C for 24 h leads to a transparent colloidal solution of nanosized crystallized anatase TiO2. The adjustment of the particle size and composition of the dispersant is monitored through the initial water content while controlling the conversion of propylene carbonate into propylene glycol during reflux. The solutions were processed as thin films to produce electron transporting layers in hybrid bulk heterojunction solar cells, by using a blend of P3HT:PCBM polymers as absorbers, in inverted architectures. The solutions obtained by reflux were demonstrated to produce suitable electron transporting layers.
Selection of a Single Isotope of Multiply Charged Xenon (AXez+, A=128–136, z=1–6) by Using a Bradbury–Nielsen Ion Gate
Authors: Kitashoji Akihiro , Yoshikawa Taiki , Fujihara Akimasa , Kamamori Takaaki , Nashima Shigeki , Yatsuhashi Tomoyuki 
Published: June 2017

AbstractThe inclusion of an ion gate in a tandem mass spectrometer allows a specific precursor ion to be selected, and the fragment ions are then used for structure analysis and to investigate chemical reactions. However, the performance of an ion gate has been judged simply by whether or not the target ion was selected. In this study, we designed, manufactured, constructed, and characterized a Bradbury–Nielsen ion gate (BNG). The actual ion selection ability, i.e. the gate function, of the BNG was measured for isotopes of Xez+ (z=1–6). The gate function of the BNG was 36.5±0.5 ns in width and 3–13 ns in rise and fall times. The BNG provides a simple way to select multiply charged molecular cations of small organic molecules as well as large molecules such as proteins and peptides.