bluuebunny/crossref_metadata_2025_split huggingface dataset:
Copper‐Catalyzed Defluorinative Thioannulation of Trifluoropropynes for the Synthesis of 1,2‐Dithiole‐3‐thiones
Authors: Wei Feng , Shen Xiao‐Qin , Zhang Xiao‐Hong , Zhang Xing‐Guo 
Published: August 2018

AbstractA simple and practical strategy for the preparation of 1,2‐dithiole‐3‐thionesviacopper‐catalyzed defluorinative thioannulation of trifluoropropynes has been developed using elemental sulfur as the sole sulfur source. This reaction displays a wide substrate scope and high functional group tolerance to afford the corresponding S‐heterocycles in moderate to good yields and features efficient construction of multiple C−S bonds through C−F bond cleavage of CF3groups.magnified image
Selective Hydroarylation of 1,3‐Diynes Using a Dimeric Manganese Catalyst: Modular Synthesis of Z‐Enynes
Authors: Yan Zhongfei , Yuan Xiang‐Ai , Zhao Yue , Zhu Chengjian , Xie Jin 
Published: August 2018

AbstractThe transition‐metal‐catalyzed selective hydroarylation of unsymmetrical alkynes represents the state‐of‐art in organic chemistry, and still mainly relies on the use of precious late‐transition‐metal catalysts. Reported herein is an unprecedented MnI‐catalyzed hydroarylation of unsymmetrical 1,3‐diyne alcohols with commercially available arylboronic acids with predictive selectivity. This method addresses the challenges in regio‐, stereo‐, and chemoselectivity. It offers a general, convenient and practical strategy for the modular synthesis of multisubstituted Z‐configurated conjugated enynes. This protocol is distinguished by its operational simplicity, complete selectivity, excellent functional‐group compatibility, and gram‐scale potential. A dimeric MnI species, Mn2(CO)8Br2, was proven to be a much more efficient catalyst precursor than Mn(CO)5Br.
High‐Capacity Upconversion Wavelength and Lifetime Binary Encoding for Multiplexed Biodetection
Authors: Zhou Lei , Fan Yong , Wang Rui , Li Xiaomin , Fan Lingling , Zhang Fan 
Published: August 2018

AbstractOptical multiplexing plays an important role in fields ranging from advanced biological assays to security. However, conventional codes based on fluorescent color and intensity are limited to spectral overlap and background interference. Herein, we present a new multiplexing concept by manipulating the luminescence emission color and decay lifetimes of upconversion nanoparticles (τλ‐UCNPs) separately for the first time through designing the core/multi‐shell structure and controlled energy relay method. This new color/lifetime binary strategy exhibits exponentially scalable encoding capacity (>105), three orders of magnitudes higher than that of conventional color/intensity way. The strategy enables the multiplexed detection of human papilloma virus (HPV) subtypes in patient samples and robust anti‐counterfeiting. This work opens new opportunities for optical multiplexing with luminescent materials.
Regioselektive metall‐ und reagenzfreie Arylierung von Benzothiophenen durch dehydrierende Elektrosynthese
Authors: Lips Sebastian , Schollmeyer Dieter , Franke Robert , Waldvogel Siegfried R. 
Published: August 2018

AbstractEine neue Strategie für die Synthese von Biarylverbindungen, die aus einer Benzothiophen‐ und einer Phenoleinheit bestehen, wird berichtet. Diese Heterobiaryle sind für pharmazeutische, biologische und leistungsfähige optoelektronische Anwendungen von großem Interesse. Durch ein metall‐ und reagenzfreies, elektrosynthetisches und hochwirksames Verfahren werden 2‐ oder 3‐(Hydroxyphenyl)benzo[b]thiophene regioselektiv gewonnen. Die beschriebene einstufige Synthese ist einfach durchzuführen, skalierbar und inhärent sicher. Die Produkte werden in hohen Ausbeuten bis zu 88 % und hervorragender Selektivität isoliert. Das Verfahren zeichnet sich zudem durch ein breites Eduktspektrum aus und toleriert eine Vielzahl von funktionellen Gruppen.
Hydrogenation of CO2‐Derived Carbonates and Polycarbonates to Methanol and Diols by Metal–Ligand Cooperative Manganese Catalysis
Authors: Zubar Viktoriia , Lebedev Yury , Azofra Luis Miguel , Cavallo Luigi , El‐Sepelgy Osama , Rueping Magnus 
Published: August 2018

AbstractThe first base‐metal‐catalysed hydrogenation of CO2‐derived carbonates to alcohols is presented. The reaction proceeds under mild conditions in the presence of a well‐defined manganese complex with a loading as low as 0.25 mol %. The non‐precious‐metal homogenous catalytic system provides an indirect route for the conversion of CO2 into methanol with the co‐production of value‐added (vicinal) diols in yields of up to 99 %. Experimental and computational studies indicate a metal–ligand cooperative catalysis mechanism.
Spirofused and Annulated 1,2,4‐Trioxepane‐, 1,2,4‐Trioxocane‐, and 1,2,4‐Trioxonane‐Cyclohexadienones: Cyclic Peroxides with Unusual Ring Conformation Dynamics
Authors: Eske Angelika , Ecker Sabrina , Fendinger Carolina , Goldfuss Bernd , Jonen Matthis , Lefarth Jens , Neudörfl Jörg‐M. , Spilles Matthias , Griesbeck Axel G. 
Published: August 2018

AbstractC3‐ or C4‐hydroxyalkylated phenols are highly reactive towards peroxidation with oxone, which results in the formation of tertiary C3 hydroperoxides. This reaction can also be performed with photochemically generated singlet oxygen. However, other characteristic singlet oxygen reactions do not proceed with caroate. The initially formed hydroperoxides cyclize in the presence of a Lewis acid catalyst based on boron, indium, or iron to give spiroannulated peroxides. These exhibit restricted ring inversion whereas larger nine‐membered‐ring peroxides are thermally less stable and show higher ring flexibility (according to NMR analysis).
Modular Redesign of a Cationic Lytic Peptide To Promote the Endosomal Escape of Biomacromolecules
Authors: Azuma Yusuke , Imai Haruka , Kawaguchi Yoshimasa , Nakase Ikuhiko , Kimura Hiroshi , Futaki Shiroh 
Published: August 2018

AbstractEndocytosis is an important route for the intracellular delivery of biomacromolecules, wherein their inefficient endosomal escape into the cytosol remains a major barrier. Based on the understanding that endosomal membranes are negatively charged, we focused on the potential of cationic lytic peptides for developing endosomolysis agents to release such entrapped molecules. As such, a venom peptide, Mastoparan X, was employed and redesigned to serve as a delivery tool. Appending a tri‐glutamate unit to the N‐terminus attenuates the cytotoxicity of Mastoparan X by about 40 fold, while introduction of a NiII‐dipicolylamine complex enhances cellular uptake of the peptide by about 17 fold. Using the optimized peptide, various fluorescently labeled macromolecules were successfully delivered to the cytosol, enabling live‐cell imaging of acetylated histones.
Plant RuBisCo: An Underutilized Protein for Food Applications
Authors: Di Stefano Elisa , Agyei Dominic , Njoku Emmanuel N. , Udenigwe Chibuike C. 
Published: August 2018

AbstractMalnutrition is a public health concern and chronic protein malnutrition is prevalent in early childhood in many developing countries. Plant proteins are good candidates for meeting the growing protein needs. RuBisCo (ribulose‐1,5‐bisphosphate carboxylase/oxygenase) is a photosynthetic enzyme that exists in 4 forms (I, II, III, and IV), with form I being characteristic of higher plants. Form I RuBisCo represents 50% of leaf proteins, and is, therefore, important as a source of protein for nutrition and as a functional ingredient, although the laborious extraction process for plant proteins can limit their use in food products. Column chromatography is the most effective RuBisCo purification step for laboratory research, while ultrafiltration has shown prospects for large‐scale applications. RuBisCo has excellent solubility in alkaline pH and at low denaturation temperatures. Thus, RuBisCo can form brittle gels at low concentrations, which can influence the chemosensory properties of products containing the proteins. Foaming of RuBisCo occurs around its isoelectric point, while emulsifying capacity proportionally increases with pH. Heating prior to emulsification increased the strength and stability of emulsion formed with RuBisCo. The protein is also attractive due to its high nutritional values and in vitro digestibility. Furthermore, RuBisCo is a competitive source of bioactive peptides with opioid‐like, memory‐enhancing, appetite‐stimulating, antioxidative, and antihypertensive properties, demonstrating the wide range of food applications where RuBisCo can be utilized.
Double layer aligned‐graphene nanosheets/styrene‐butadiene rubber composites: Tribological and mechanical properties
Authors: Wang Fei , Mao Jian 
Published: August 2018

ABSTRACTWe enhanced tribological and mechanical properties of styrene‐butadiene rubber (SBR) by designing double layer aligned‐graphene nanosheets (aligned‐GNSs)/SBR composites with one‐step emulsion polymerization preparation method. The composites consisted of two layers, one is the SBR layer and the other is aligned‐GNSs/SBR layer, in which the graphene nanosheets (GNSs) regularly aligned. The resulted composites exhibited mega increase of tribological property as well as mechanical property. With the increase of GNSs contents from 0.5 to 5 wt %, both the friction coefficient and volume wear rate steadily declined, and the mechanics dramatically increased. Such as 59% decrease of friction coefficient and 1778% increase of the initial tensile modulus when the addition of GNSs is 5 wt %. The above results are mainly due to the well aligned‐GNSs in SBR, which can take full advantage of the unique properties of GNSs two‐dimensional materials. The detailed mechanisms of improving tribological and mechanical properties were discussed in the study. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 46939.
Die‐offs of the endangered pearl mussel Margaritifera margaritifera during an extreme drought
Authors: Sousa Ronaldo , Ferreira André , Carvalho Francisco , Lopes‐Lima Manuel , Varandas Simone , Teixeira Amílcar 
Published: August 2018

Abstract

Droughts may be responsible for important ecological impacts in freshwater ecosystems, including the death of rare species.
This study assessed the mortality of the endangered pearl mussel Margaritifera margaritifera (Linnaeus, 1758) in the Mente, Rabaçal and Tuela rivers (north west of the Iberian Peninsula) during the extreme summer drought of 2017.
Mortality occurred as a result of the low river flow, which led to mussel stranding near the banks and consumption (by predation or scavenging) by wild boar Sus scrofa (Linnaeus, 1758).
Mortality differed across sites. The shell lengths of live mussels (measured before the drought) and dead mussels significantly differed in the Rabaçal River, but not in the Mente and Tuela rivers.
Extreme droughts are predicted to increase in number and intensity in the future, and possible impacts on rare species such as M. margaritifera should be carefully monitored. Several M. margaritifera populations in Iberia (and elsewhere) may now be at increased risk, and measures should be implemented in order to mitigate the impacts of future extreme droughts.
The effect of regional sea surface temperature rise on fisheries along the Portuguese Iberian Atlantic coast
Authors: Leitão Francisco , Maharaj Ravi R. , Vieira Vasco M.N.C.S. , Teodósio Alexandra , Cheung William W.L. 
Published: August 2018

Abstract

The environmental effects of climate change are expected to impact fisheries, and related economies, and represent a significant challenge for the development of government policy. The impact of ocean warming on fisheries yields is of particular concern.
The effect of sea surface temperature (SST) on fisheries in three distinct biogeographic areas (north‐western, NW; south‐western, SW; and south, S) and different fleet sectors (trawl, seine, and multi‐gear) of the Portuguese coast was examined.
The mean temperature of the catch (MTC) was applied to the official landings statistics to assess the effect of global warming on the exploited marine communities. MTC increased from 16.9, 16.7, and 17.4°C in 1989 to 17.9, 18.1, and 18.3°C in 2009, whereas the linear rate of MTC increase was 0.54, 0.49, and 0.70°C per decade in the NW, SW, and S regions, respectively.
The increase of warmer species in fisheries landings is regional‐specific. The percentage increases in landings of warmer water species increased significantly from north to south: 5.1, 6.7, and 18% per decade in the NW, SW, and S, respectively.
The results confirmed that ocean warming has affected the composition of fisheries landings (of warmer and colder species) in the three regions of the Portuguese coast. The results highlight the importance and urgency of considering the temperature‐induced shift in species distribution in fisheries management.
The Alliance for Freshwater Life: A global call to unite efforts for freshwater biodiversity science and conservation
Authors: Darwall William , Bremerich Vanessa , De Wever Aaike , Dell Anthony I. , Freyhof Jörg , Gessner Mark O. , Grossart Hans‐Peter , Harrison Ian , Irvine Ken , Jähnig Sonja C. , Jeschke Jonathan M. , Lee Jessica J. , Lu Cai , Lewandowska Aleksandra M. , Monaghan Michael T. , Nejstgaard Jens C. , Patricio Harmony , Schmidt‐Kloiber Astrid , Stuart Simon N. , Thieme Michele , Tockner Klement , Turak Eren , Weyl Olaf 
Published: August 2018

Abstract

Global pressures on freshwater ecosystems are high and rising. Viewed primarily as a resource for humans, current practices of water use have led to catastrophic declines in freshwater species and the degradation of freshwater ecosystems, including their genetic and functional diversity. Approximately three‐quarters of the world's inland wetlands have been lost, one‐third of the 28 000 freshwater species assessed for the International Union for Conservation of Nature (IUCN) Red List are threatened with extinction, and freshwater vertebrate populations are undergoing declines that are more rapid than those of terrestrial and marine species. This global loss continues unchecked, despite the importance of freshwater ecosystems as a source of clean water, food, livelihoods, recreation, and inspiration.
The causes of these declines include hydrological alterations, habitat degradation and loss, overexploitation, invasive species, pollution, and the multiple impacts of climate change. Although there are policy initiatives that aim to protect freshwater life, these are rarely implemented with sufficient conviction and enforcement. Policies that focus on the development and management of fresh waters as a resource for people almost universally neglect the biodiversity that they contain.
Here we introduce the Alliance for Freshwater Life, a global initiative, uniting specialists in research, data synthesis, conservation, education and outreach, and policymaking. This expert network aims to provide the critical mass required for the effective representation of freshwater biodiversity at policy meetings, to develop solutions balancing the needs of development and conservation, and to better convey the important role freshwater ecosystems play in human well‐being. Through this united effort we hope to reverse this tide of loss and decline in freshwater biodiversity. We introduce several short‐ and medium‐term actions as examples for making positive change, and invite individuals, organizations, authorities, and governments to join the Alliance for Freshwater Life.
Discovery of the Romanesque church of the Abbey of our lady of Bec (Le Bec‐Hellouin, Normandy, France) by means of geophysical methods
Authors: Fauchard Cyrille , Saley Abdoulaziz Djibrila , Camerlynck Christian , Fargier Yannick , Antoine Raphael , Thérain Paul‐Franck 
Published: August 2018

AbstractA geophysical survey was carried out in 2015 for the development of the patrimonial site of the Abbey of Our Lady of Bec (also called the Bec Abbey), located in Le Bec‐Héllouin, Normandy, France. This survey aimed at optimizing the future accessibility programme by preserving the historical heritage of the Bec Abbey, taking into account potential underground remains. The ground penetrating radar (GPR), the electrical resistivity imaging (ERI) and the magnetic method (MM) were used to prospect the shallow surface. The GPR imaging shows longitudinal and curvated structures, drawing the classical and simplified plan of a Romanesque church basement of the eleventh century. This is the most important discovery of this survey, since the existence of this church was historically known but has remained unlocated till this geophysical survey. The ERI measurements confirm and locally complete most of the GPR results. Despite the very magnetic‐noisy environment, the MM investigation is the only method detecting a longitudinal structure that can be the foundation of an ancient wall between the Saint Nicolas' tower and the church nave of the thirteenth century. Finally, authorities recently allowed in July 2017 the publication of excavations performed by archaeologists. Most of the geophysical anomalies have helped to target the archaeological investigation and the results provide a detailled interpretation in terms of depth and nature of remnants. Archaeological investigation then offers an important historical outcome of the various stages of construction and destruction of the Bec Abbey.
An approximate Bayesian significance test for genomic evaluations
Authors: Wittenburg Dörte , Liebscher Volkmar 
Published: August 2018

AbstractGenomic information can be used to study the genetic architecture of some trait. Not only the size of the genetic effect captured by molecular markers and their position on the genome but also the mode of inheritance, which might be additive or dominant, and the presence of interactions are interesting parameters. When searching for interacting loci, estimating the effect size and determining the significant marker pairs increases the computational burden in terms of speed and memory allocation dramatically. This study revisits a rapid Bayesian approach (fastbayes). As a novel contribution, a measure of evidence is derived to select markers with effect significantly different from zero. It is based on the credibility of the highest posterior density interval next to zero in a marginalized manner. This methodology is applied to simulated data resembling a dairy cattle population in order to verify the sensitivity of testing for a given range of type‐I error levels. A real data application complements this study. Sensitivity and specificity of fastbayes were similar to a variational Bayesian method, and a further reduction of computing time could be achieved. More than 50% of the simulated causative variants were identified. The most complex model containing different kinds of genetic effects and their pairwise interactions yielded the best outcome over a range of type‐I error levels. The validation study showed that fastbayes is a dual‐purpose tool for genomic inferences – it is applicable to predict future outcome of not‐yet phenotyped individuals with high precision as well as to estimate and test single‐marker effects. Furthermore, it allows the estimation of billions of interaction effects.
Spectroscopic investigations of nanosized Cr3+ doped Sc2−xInx(WO4)3: A new promising laser material
Authors: Yordanova A. , Iordanova R. , Koseva I. , Nikolov V. , Kukeva R. 
Published: August 2018

AbstractChromium(III) doped nanosized Sc2−xInx(WO4)3, (x = 0–2) solid solutions were prepared by the co‐precipitation/calcination method. The obtained powders were characterized using X‐ray diffraction (XRD), electron paramagnetic resonance (EPR), infrared (IR), absorption and luminescence spectra. X‐ray analysis showed that the compounds are pure solid solutions with orthorhombic symmetry at x values 0 and 0.5 and with monoclinic symmetry for x values 1.0, 1.5 and 2.0. The calculated crystallite size ranged from about 20 to 110 nm, except for Sc2(WO4)3 characterized by considerably larger sizes. IR spectra of the solid solutions contain the characteristic vibrations of the WO4 and MeO6, (Me = Sc, In) polyhedra, building the Sc2(WO4)3 and In2(WO4)3 structures. EPR analysis proved the presence of isolated Cr3+ ions in the crystal field with rhombic symmetry. The presence of Cr3+ in sites with weak and strong crystal field was revealed by absorption and luminescence spectra. This study demonstrates the effect of hosts crystal symmetry, particles size and doping concentration on the luminescence properties.
Optimization of extraction and analytical protocol for mass spectrometry‐based metabolomics analysis of hepatotoxicity
Authors: Yang Rui , Zhao Qi , Hu Dan‐Dan , Xiao Xue‐Rong , Li Fei 
Published: August 2018

AbstractDrug‐induced liver injury is a clinically leading side‐effect of drugs. In the present study, a liquid chromatography mass spectrometry‐based metabolomics protocol was optimized for extraction and analysis of endogenous metabolites from liver tissue during hepatotoxicity. Various extraction solutions, resuspension solutions, extraction folds and dissolution methods for the supernatant were compared using the number of extracted total ions, relative response and relative extraction efficiency of targeted metabolites from liver tissue. The polar and nonpolar endogenous metabolites associated with liver injury were analyzed by hydrophilic interaction chromatography and reversed‐phase liquid chromatography with UPLC–QTOFMS. The results indicated that extraction with 10‐fold 50% acetonitrile in water and the supernatant diluted (1:1) with 100% acetonitrile rather than resuspension was the optimal extraction protocol. Subsequently, the optimized method was able to examine the change in metabolites in mouse liver tissue resulting from treatment with a toxic natural product, toosendanin. Taken together, the optimized extraction and analytical protocol provides high reliability and reproducibility for polar and nonpolar metabolites in liver tissue and may be suitable for metabolomics analysis of liver injury induced by drugs or chemicals.
Coexpression of 5‐Aminolevulinic Acid Synthase Gene Facilitates Heterologous Production of Thermostable Cytochrome P450, CYP119, in Holo Form in Escherichia coli
Authors: Honda Yuki , Nanasawa Kii , Fujii Hiroshi 
Published: August 2018

AbstractCytochrome P450 enzymes are heme‐containing monooxygenases that exhibit potential as biocatalysts for practical applications. The Escherichia coli expression system is frequently used for biocatalyst production; however, heterologous production of hemeproteins in their holo form is difficult due to insufficient heme synthesis by the host. In this study, 5‐aminolevulinic acid synthase (ALAS) from Rhodobacter capsulatus is used to accelerate intracellular heme biosynthesis in E. coli; this demonstrates that coexpression of the ALAS gene (ALAS) improves the heterologous production of cytochrome P450, CYP119, from Sulfolobus acidocaldarius. Coexpression of ALAS increased the amount of heterologous CYP119 isolated and the ratio of its holo form. The ratio of holo‐CYP119 resulting from the coexpression of ALAS in E. coli was 99 %, whereas that from cells expressing CYP119 exclusively was 66 %. Coexpression of ALAS is a promising alternative for the efficient heterologous production of hemeproteins by using E. coli.