bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gold(I)‐Catalyzed Desymmetrization of 1,4‐Dienes by an Enantioselective Tandem Alkoxylation/Claisen Rearrangement
Authors: Wu Hongmiao , Zi Weiwei , Li Guigen , Lu Hongjian , Toste F. Dean 
Published: June 2015

AbstractAn enantioselective alkoxylation/Claisen rearrangement reaction was achieved by a strategic desymmetrization of 1,4‐dienes under the catalysis of (S)‐DTBM‐Segphos(AuCl)2/AgBF4. This reaction system was highly selective for the formation of 3,3‐rearrangement products, providing cycloheptenes with various substitutions in good yield and good to excellent enantioselectivity. This transformation was further extended to bicyclic ring substrates, providing the opportunity to easily assemble 5,6‐ and 6,7‐fused ring systems.
Genetic variation affects congenital heart defect susceptibility in offspring exposed to maternal tobacco use
Authors: Tang Xinyu , Hobbs Charlotte A. , Cleves Mario A. , Erickson Stephen W. , MacLeod Stewart L. , Malik Sadia ,   the National Birth Defects Prevention Study
Published: June 2015

BackgroundCongenital heart defects (CHDs) are among the most prevalent and serious birth defects, occurring in 8 to 10 of every 1000 live births in the United States. Epidemiologic studies have reported an association between CHDs and maternal smoking, but it remains unknown how genes impact the susceptibility of offspring to CHDs in the presence of maternal tobacco use.MethodsUsing data from 403 case‐ and 219 control‐parental triads enrolled in the National Birth Defects Prevention Study between 1998 and 2008, we investigated the association between CHDs and maternal and infant genetic variants involved in the tobacco metabolism and DNA repair pathways among mothers who smoked prenatally.ResultsThe maternal genotypes of single nucleotide polymorphisms in the excision repair cross‐complementation group 1 (ERCC1), poly (ADP‐ribose) polymerase 2 (PARP2), and ERCC5 genes were identified to be significantly associated with the occurrence of CHDs in the presence of maternal tobacco use. Our analysis also revealed a moderate association between the infant genotypes of polymorphisms in the O‐sialoglycoprotein endopeptidase (OSGEP) gene and increased risk of CHDs among mothers who smoked.ConclusionOur study provides evidence that maternal and infant polymorphisms within the ERCC1, PARP2, ERCC5, and OSGEP genes are associated with CHD risk in the presence of maternal tobacco use. These results may provide insight into the susceptibility of having a pregnancy affected by CHDs among women who smoke. Birth Defects Research (Part A) 103:834–842, 2015. © 2015 Wiley Periodicals, Inc.
A novelin situgas stripping‐pervaporation process integrated with acetone‐butanol‐ethanol fermentation for hyper n‐butanol production
Authors: Xue Chuang , Liu Fangfang , Xu Mengmeng , Zhao Jingbo , Chen Lijie , Ren Jiangang , Bai Fengwu , Yang Shang‐Tian 
Published: June 2015

ABSTRACTButanol is considered as an advanced biofuel, the development of which is restricted by the intensive energy consumption of product recovery. A novel two‐stage gas stripping‐pervaporation process integrated with acetone‐butanol‐ethanol (ABE) fermentation was developed for butanol recovery, with gas stripping as the first‐stage and pervaporation as the second‐stage using the carbon nanotubes (CNTs) filled polydimethylsiloxane (PDMS) mixed matrix membrane (MMM). Compared to batch fermentation without butanol recovery, more ABE (27.5 g/L acetone, 75.5 g/L butanol, 7.0 g/L ethanol vs. 7.9 g/L acetone, 16.2 g/L butanol, 1.4 g/L ethanol) were produced in the fed‐batch fermentation, with a higher butanol productivity (0.34 g/L · h vs. 0.30 g/L · h) due to reduced butanol inhibition by butanol recovery. The first‐stage gas stripping produced a condensate containing 155.6 g/L butanol (199.9 g/L ABE), which after phase separation formed an organic phase containing 610.8 g/L butanol (656.1 g/L ABE) and an aqueous phase containing 85.6 g/L butanol (129.7 g/L ABE). Fed with the aqueous phase of the condensate from first‐stage gas stripping, the second‐stage pervaporation using the CNTs‐PDMS MMM produced a condensate containing 441.7 g/L butanol (593.2 g/L ABE), which after mixing with the organic phase from gas stripping gave a highly concentrated product containing 521.3 g/L butanol (622.9 g/L ABE). The outstanding performance of CNTs‐PDMS MMM can be attributed to the hydrophobic CNTs giving an alternative route for mass transport through the inner tubes or along the smooth surface of CNTs. This gas stripping‐pervaporation process with less contaminated risk is thus effective in increasing butanol production and reducing energy consumption. Biotechnol. Bioeng. 2016;113: 120–129. © 2015 Wiley Periodicals, Inc.
Light‐field‐characterization in a continuous hydrogen‐producing photobioreactor by optical simulation and computational fluid dynamics
Authors: Krujatz Felix , Illing Rico , Krautwer Tobias , Liao Jing , Helbig Karsten , Goy Katharina , Opitz Jörg , Cuniberti Gianaurelio , Bley Thomas , Weber Jost 
Published: June 2015

ABSTRACTExternally illuminated photobioreactors (PBRs) are widely used in studies on the use of phototrophic microorganisms as sources of bioenergy and other photobiotechnology research. In this work, straightforward simulation techniques were used to describe effects of varying fluid flow conditions in a continuous hydrogen‐producing PBR on the rate of photofermentative hydrogen production (rH2) by Rhodobacter sphaeroides DSM 158. A ZEMAX optical ray tracing simulation was performed to quantify the illumination intensity reaching the interior of the cylindrical PBR vessel. 24.2% of the emitted energy was lost through optical effects, or did not reach the PBR surface. In a dense culture of continuously producing bacteria during chemostatic cultivation, the illumination intensity became completely attenuated within the first centimeter of the PBR radius as described by an empirical three‐parametric model implemented in Mathcad. The bacterial movement in chemostatic steady‐state conditions was influenced by varying the fluid Reynolds number. The “Computational Fluid Dynamics” and “Particle Tracing” tools of COMSOL Multiphysics were used to visualize the fluid flow pattern and cellular trajectories through well‐illuminated zones near the PBR periphery and dark zones in the center of the PBR. A moderate turbulence (Reynolds number = 12,600) and fluctuating illumination of 1.5 Hz were found to yield the highest continuous rH2 by R. sphaeroides DSM 158 (170.5 mL L−1 h−1) in this study. Biotechnol. Bioeng. 2015;112: 2439–2449. © 2015 Wiley Periodicals, Inc.
Multivariate analysis of PRISMA optimized TLC image for predicting antioxidant activity and identification of contributing compounds from Pereskia bleo
Authors: Sharif K. M. , Rahman M. M. , Azmir J. , Khatib A. , Sabina E. , Shamsudin S. H. , Zaidul I. S. M. 
Published: June 2015

AbstractMultivariate analysis of thin‐layer chromatography (TLC) images was modeled to predict antioxidant activity of Pereskia bleo leaves and to identify the contributing compounds of the activity. TLC was developed in optimized mobile phase using the ‘PRISMA’ optimization method and the image was then converted to wavelet signals and imported for multivariate analysis. An orthogonal partial least square (OPLS) model was developed consisting of a wavelet‐converted TLC image and 2,2‐diphynyl‐picrylhydrazyl free radical scavenging activity of 24 different preparations of P. bleo as the x‐ and y‐variables, respectively. The quality of the constructed OPLS model (1 + 1 + 0) with one predictive and one orthogonal component was evaluated by internal and external validity tests. The validated model was then used to identify the contributing spot from the TLC plate that was then analyzed by GC‐MS after trimethylsilyl derivatization. Glycerol and amine compounds were mainly found to contribute to the antioxidant activity of the sample. An alternative method to predict the antioxidant activity of a new sample of P. bleo leaves has been developed. Copyright © 2015 John Wiley & Sons, Ltd.
Palladium Nanoparticles Supported on Sulfonic Acid Functionalized Silica as Trifunctional Heterogeneous Catalysts for Heck and Suzuki Reactions
Authors: Oger Nicolas , Le Grognec Erwan , Felpin François‐Xavier 
Published: June 2015

AbstractThe arylation of acrylates and boronic acids with anilines, through in situ generated aryl diazonium salts, was successfully achieved by using trifunctional heterogeneous catalysts bearing Brønsted acid and metal active sites. The trifunctional materials were prepared by adsorption of palladium nanoparticles, generated by reduction of a solution of Pd(OAc)2 onto a commercially available sulfonic acid functionalized silica. These new trifunctional catalysts act as a 1) proton donor for the diazotization step, 2) counterion for the diazonium salt, and 3) Pd source for the coupling step. This unprecedented strategy, features mild and safe conditions as hazardous aryl diazonium salts are generated in situ and only produces environmentally friendly byproducts such as tBuOH, H2O, and N2.
Highly Stereoselective [4+2] and [3+2] Spiroannulations of 2‐(2‐Oxoindolin‐3‐ylidene)acetic Esters Catalyzed by Bifunctional Thioureas
Authors: Monari Magda , Montroni Elisa , Nitti Andrea , Lombardo Marco , Trombini Claudio , Quintavalla Arianna 
Published: June 2015

AbstractA new Michael–Michael cascade reaction between 2‐(2‐oxoindolin‐3‐ylidene)acetic esters 1 and nitroenoates 2, catalyzed by bifunctional thioureas, is investigated. The combination of the two Michael reactions results in a novel and facile [4+2] or [3+2] spiroannulation process, which is characterized by the following features: 1) two carbon–carbon bonds and four stereocenters, including a quaternary spiro carbon, are formed under mild conditions; 2) an unprecedented and stereochemically defined substitution pattern on the spirocarbocyclic unit is obtained; 3) the double‐bond configuration of the donor–acceptor nitroenoate 2 determines the absolute configuration of the spiro center, whereas the remaining stereocenters are formed under control of the catalyst. The effect on the final stereochemical outcome of structural variations of each starting material, catalyst, and experimental conditions is analyzed in detail. In particular, the use of specifically designed chiral nitroenoates enables diverse polyfunctional spirocyclohexane derivatives containing six consecutive stereogenic centers to be constructed. To our knowledge, this is the first asymmetric organocatalytic strategy enabling both five‐ and six‐membered β‐nitro spirocarbocyclic oxindoles.
A Modular Synthesis of Modified Phosphoanhydrides
Authors: Hofer Alexandre , Cremosnik Gregor S. , Müller André C. , Giambruno Roberto , Trefzer Claudia , Superti‐Furga Giulio , Bennett Keiryn L. , Jessen Henning J. 
Published: June 2015

AbstractPhosphoanhydrides (P‐anhydrides) are ubiquitously occurring modifications in nature. Nucleotides and their conjugates, for example, are among the most important building blocks and signaling molecules in cell biology. To study and manipulate their biological functions, a diverse range of analogues have been developed. Phosphate‐modified analogues have been successfully applied to study proteins that depend on these abundant cellular building blocks, but very often both the preparation and purification of these molecules are challenging. This study discloses a general access to P‐anhydrides, including different nucleotide probes, that greatly facilitates their preparation and isolation. The convenient and scalable synthesis of, for example, 18O labeled nucleoside triphosphates holds promise for future applications in phosphoproteomics.
Engineering Homochiral Metal–Organic Frameworks by Spatially Separating 1D Chiral Metal–Peptide Ladders: Tuning the Pore Size for Enantioselective Adsorption
Authors: Stylianou Kyriakos C. , Gómez Laura , Imaz Inhar , Verdugo‐Escamilla Cristóbal , Ribas Xavi , Maspoch Daniel 
Published: June 2015

AbstractThe reaction of the chiral dipeptide glycyl‐L(S)‐glutamate with CoII ions produces chiral ladders that can be used as rigid 1D building units. Spatial separation of these building units with linkers of different lengths allows the engineering of homochiral porous MOFs with enhanced pore sizes, pore volumes, and surface areas. This strategy enables the synthesis of a family of isoreticular MOFs, in which the pore size dictates the enantioselective adsorption of chiral molecules (in terms of their size and enantiomeric excess).
When do MNCs fail to learn from prior failure experience?
Authors: Hong Sungjin J. 
Published: June 2015

AbstractDo multinational corporations (MNCs) learn from their prior failures in international joint ventures (IJVs)? When does decision makers’ cognitive inability hinder MNCs from learning through their prior failure experiences? In the context of IJV survival in subsequent IJV entries, this study compares predictions made from two distinct theoretical perspectives, both of which belong to the behavioural school in strategy literature. According to the performance feedback perspective, MNCs may effectively learn from their prior failure experiences gained in familiar decision‐making contexts. On the other hand, according to the cognitive bias perspective, MNCs may not be able to effectively learn from their prior failure experiences if they inaccurately interpret the causes of their prior failures. The results provide partial support for the notion that MNC decision makers may not be able to effectively learn from their prior failures because of their cognitive biases. Copyright © 2015 ASAC. Published by John Wiley & Sons, Ltd.
Design and validation of conditional ligands for HLA‐B*08:01, HLA‐B*15:01, HLA‐B*35:01, and HLA‐B*44:05
Authors: Frøsig Thomas Mørch , Yap Jiawei , Seremet Tina , Lyngaa Rikke , Svane Inge Marie , Thor Straten Per , Heemskerk Mirjam H. M. , Grotenbreg Gijsbert M. , Hadrup Sine Reker 
Published: June 2015

AbstractWe designed conditional ligands restricted to HLA‐B*08:01, −B*35:01, and −B*44:05 and proved the use of a conditional ligand previously designed for HLA‐B*15:02 together with HLA‐B*15:01. Furthermore, we compared the detection capabilities of specific HLA‐B*15:01‐restricted T cells using the HLA‐B*15:01 and HLA‐B*15:02 major histocompatibility complex (MHC) multimers and found remarkable differences in the staining patterns detected by flow cytometry. These new conditional ligands greatly add to the application of MHC‐based technologies in the analyses of T‐cell recognition as they represent frequently expressed HLA‐B molecules. This expansion of conditional ligands is important to allow T‐cell detection over a wide range of HLA restrictions, and provide comprehensive understanding of the T‐cell recognition in a given context. © 2015 International Society for Advancement of Cytometry
Hybrid mesh generation using advancing reduction technique
Authors: Zhang Yaoxin , Jia Yafei 
Published: June 2015

SummaryThis paper presents an application of the advancing reduction technique for 2D hybrid mesh generation (triangles + quadrilaterals). Based on an initial rectangle mesh (RM) covering the whole domain, the advancing reduction technique coarsens the base RM in a marching way from the boundary to the interior of the domain so that different zones of sub‐RMs with different edge lengths are recognized. These sub‐RMs are connected to each other with the so‐called transition layers which consist of the transition triangles and quadrilaterals. As demonstrated by examples, the proposed method is simple, efficient, and easy to implement. Copyright © 2015 John Wiley & Sons, Ltd.
Shortened directional coupler using slow wave structure of periodically loaded capacitance and inductance
Authors: Zhong Cuilin , Yu Fengqi , Sun Yuanpeng , Nie Wei , Wang Maoyan 
Published: June 2015

AbstractThis paper proposes an analytically based approach for the design of a length‐reduced directional coupler. This method of reduction is realizing the directional coupler's impedance transformers by using slow wave structures. These slow wave structures are designed by transmission lines periodically loading both shunt capacitances and series inductances. Loaded capacitance is realized by stub shunt capacitance on the top layer; at the same time, loaded inductance is realized by electromagnetic band gap structure on ground. Increasing parallel capacitance and series inductance can reduce the phase velocity of the propagating waves and hence engender higher electric lengths using smaller physical lengths. A directional coupler is designed using this slow wave structure, and the performance of coupling is analyzed with the generalized coupled‐mode theory. The design methodology is validated with the design of a length‐reduced directional coupler at 0.7 GHz. An approximate length reduction of 54% is achieved with this technique compared with the conventional directional coupler. The electromagnetic simulation and experimental results validate the proposed approach. Copyright © 2015 John Wiley & Sons, Ltd.
Observations‐based analysis of the summer temperature extremes in Moscow
Authors: Zyulyaeva Yulia A. , Zveryaev Igor I. , Koltermann Klaus Peter 
Published: June 2015

ABSTRACTInterannual variability and long‐term changes of summer temperature extremes and hot spells in Moscow during 1949–2012 are investigated using air temperature station data, the National Centres for Environmental Prediction/the National Centre for Atmospheric Research (NCEP/NCAR) reanalysis and the Climatic Research Unit (CRU) data sets. Significant interdecadal changes in different characteristics of the temperature extremes are revealed. It is shown that summertime warming detected in the Moscow region in recent decades is not solely due to an increase in the number of hot days, but also due to a decrease in the number of cold days. Statistically significant positive (negative) trends in the number of anomalously hot (cold) days since the mid 1970s are detected. Respective trend values are 5%/decade–1 for the positive trends and −6%/decade–1 for the negative trends. We find that in 1981–2012 the number of summer seasons with extremely hot days has doubled with respect to earlier period (1949–1980). However, we do not find statistically significant trend‐like changes in the duration of the hot events in Moscow. A chronology of temperature extremes in Moscow has been constructed. This can be used as a diagnostic tool allowing the detection of extremes. Typical regional sea level pressure patterns associated with air temperature extremes in Moscow are defined and briefly described.
Using regional climate models to simulate extreme rainfall events in the Western Cape, South Africa
Authors: Abiodun Babatunde J. , Abba Omar Sabina , Lennard Chris , Jack Chris 
Published: June 2015

ABSTRACTThis study evaluates the capability of regional climate models (RCMs) in simulating extreme rainfall events over Southern Africa, and in reproducing the characteristics of widespread extreme rainfall events (WERE) in the Western Cape (South Africa). We obtained simulation datasets of nine RCMs from the Co‐ordinated Regional Downscaling Experiment (CORDEX) and compared them with observation datasets from the Global Precipitation Climatology Project (GPCP) and Tropical Rainfall Measuring Mission (TRMM) as well as with the reanalysis dataset (ERAINT) that forced the simulations. A self‐organising map was used to classify the WEREs into 12 nodes. The contribution of each RCM to each node was compared with the contributions of GPCP, TRMM and ERAINT. Using ERAINT dataset, we analysed the synoptic‐scale atmospheric condition associated with each node.The results show that, in simulating the spatial distribution of the extreme rainfall event over Southern Africa, only four RCMs perform better than the forcing reanalysis (ERAINT) while two RCMs perform worse than the reanalysis. All the RCMs underestimate the threshold of extreme rainfall over Western Cape, poorly simulate the inter‐annual variability of the WEREs (r ≤ 0.3), but correctly reproduce the maximum frequency of the WEREs in Autumn (March–May). The WEREs in the Western Cape may be broadly grouped into four synoptic rainfall patterns. The first pattern links WEREs with tropical rainfall activities (tropical‐temperate troughs); the second pattern shows isolated WEREs; the third and fourth patterns link WEREs with rainfall activities in the mid‐latitudes (frontal systems) and over the Agulhas Current, respectively. While most RCMs overestimate the frequency of the first pattern, they all underestimate the frequency of the second pattern but simulate the frequencies of the third and fourth patterns well. The results of this study should help in improving the RCM simulations over Southern Africa and in downscaling impacts of climate change on extreme rainfall events over the region.
Reconstruction of Block Copolymer Micelles to Long‐Range Ordered Dense Nanopatterns Via Light‐Tunable Hydrogen‐Bonding Association
Authors: Guo Lei , Ding Yi , Han Jie , Xu Na , Lu Xinhua , Cai Yuanli 
Published: June 2015

Controlling the orientation and long‐range order of nanostructures is a key issue in the self‐assembly of block copolymer micelles. Herein, a versatile strategy is presented to transform one‐component oxime‐based block copolymer micelles into long‐range ordered dense nanopatterns. Photoisomerization provides a straightforward and versatile approach to convert the hydrogen‐bonding association from inward dimerization (E‐type oxime motifs, slightly desolvated in ethyl acetate) into outward interchain association (Z‐type ones, highly desolvated in ethyl acetate). This increases the glass transition temperature in bulk and converts swollen micelles into compact spherical micelles in solution. The reconstruction of these micelles on various substrates demonstrates that the phase transformation enables reconstruction of spherical micelles into mesoscopic sheets, nanorods, nanoworms, nanowires, networks, and eventually into long‐range ordered and densely packed textile‐like and lamellar nanopatterns on a macroscopic scale by adjusting E/Z‐oxime ratio and solvent‐evaporation rate.
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An Update on the Hereditary Spastic Paraplegias: New Genes and New Disease Models
Authors: Kumar Kishore R. , Blair Nicholas F. , Sue Carolyn M. 
Published: June 2015

AbstractAimsThe hereditary spastic paraplegias (HSPs) are a heterogeneous group of disorders characterized by spasticity in the lower limbs. We provide an overview of HSP with an emphasis on recent developments.MethodsA PubMed search using the term “hereditary spastic paraplegia” and “hereditary spastic paraparesis” was conducted for a period from January 2012 to January 2015. We discuss and critique the major studies in the field over this 36‐month period.ResultsA total of 346 publications were identified, of which 47 were selected for review. We provide an update of the common forms of HSP and include patient videos. We also discuss how next‐generation sequencing (NGS) has led to the accelerated discovery of new HSP genes, including B4GALNT1, DDHD1, C19orf12, GBA2, TECPR2, DDHD2, C12orf65, REEP2, and IBA57. Moreover, a single study alone identified 18 previously unknown putative HSP genes and created a model for the protein interactions of HSP, called the “HSPome.” Many of the newly reported genes cause rare, complicated, autosomal recessive forms of HSP. NGS also has important clinical applications by facilitating the molecular diagnosis of HSP. Furthermore, common genetic forms of HSP have been studied using new disease models, such as neurons derived from induced pluripotent stem cells. These models have been used to elucidate important disease mechanisms and have served as platforms to screen for candidate drug compounds.ConclusionThe field of HSP research has been progressing at a rapid pace. The challenge remains in translating these advances into new targeted disease therapies.