bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phylogenomics of Snakes
Authors: Streicher Jeffrey W , Ruane Sara 
Published: February 2018

AbstractReduced representation genome sequencing has ushered in new methods for understanding how life evolved on earth. These methods utilise genetic data in the form of dozens, hundreds or even thousands of loci to estimate phylogenetic relationships. This approach, often termed phylogenomic analysis, has the potential to resolve controversial evolutionary relationships, particularly among ancient, rapid radiations. Among vertebrates, phylogenomic analyses are increasingly applied to an iconic group of reptiles, snakes. Phylogenomic analyses of snakes have begun to shed light on long‐standing questions including relationships among snake families, their origin among squamate reptiles and putative causes of speciation within recent radiations. In addition, these methods may even be used to obtain genetic data from archival museum specimens. This emerging approach for understanding snake evolution will be improved by whole genome sequencing initiatives that include a diverse group of snake species.Key ConceptsSnakes are important study systems for human physiology and medicine.Snakes are important predators in ecosystems/important to maintaining ecosystem health.Robust phylogenetic hypotheses are necessary to understand snake evolution.Genome‐wide data offer unprecedented opportunities to resolve snake phylogeny and the tree of life.Phylogenomic analyses of snakes will aid biologists and medical researchers worldwide.
Vitamin
E
Authors: Azzi Angelo 
Published: February 2018

Abstract

Vitamin E or RRR‐α‐tocopherol, as all vitamins, is indispensable for human life. Insufficient vitamin E availability results in a neurological condition, ‘ataxia with vitamin E deficiency’ (AVED), and vitamin E administration prevents the progression of the disease. Vitamin E is available especially in nuts, vegetable oils and greens. The reference daily intake for healthy adults is 15 mg and the maximum dose is 1000 mg daily. Many ailments, from cancer to atherosclerosis and neurodegenerative diseases, had been proposed to be prevented or cured by vitamin E; however, recent studies have shown that only low‐grade chronic inflammation, nonalcoholic steatohepatitis (NASH), nonalcoholic fatty liver disease (NAFLD) and immune response may benefit from vitamin E. The mechanism of action of this vitamin is still an object of debate, scientists being either in favour of an antioxidant mechanism or of an action of vitamin E on signal transduction and gene expression modulation.

Key Concepts

Low intake of vitamin E results in ataxia with vitamin E deficiency (AVED).

Administration of α‐tocopherol protects against the progression of AVED.

Vitamin E does not prevent or cure cancer, cardiovascular and neurodegenerative diseases.

Low‐grade inflammation and nonalcoholic fatty liver disease (NASH, NAFLD) are diminished by vitamin E.

Vitamin E improves the immune response, especially in the elderly.

A better knowledge of the mechanism of action of vitamin E would be useful to better use its potentials, established its correct dosage and the possible relation between genetic background of humans taking vitamin E and their response to this vitamin.
Fungal Ribotoxins
Authors: García‐Ortega Lucía , Palacios‐Ortega Juan , Martínez‐del‐Pozo Álvaro 
Published: February 2018

Abstract

Fungal ribotoxins constitute a family of extracellular ribonucleases with exquisite specificity against rRNA (ribonucleic acid). They induce apoptotic death of cells after inhibiting protein translation. Ribosomes become functionally incompetent because ribotoxins cleave one single phosphodiester bond, located at a unique and universally conserved loop, needed for elongation factors function. As secreted proteins, ribotoxins need to cross the membrane of their target cells in order to exert their catalytic activity, and they do it without receptor mediation. Using lipid model systems, it has been shown that they are able to enter cells with membranes enriched in acidic phospholipids. Both membrane‐interacting and ribosomal‐recognition activities are characterised by distinct structural features. Even though the natural function of ribotoxins is not known yet, their production by entomopathogenic fungi has suggested their insecticidal role. After decades of detailed study, the biotechnological potential of ribotoxins in pest control and as antitumour agents is becoming evident.

Key Concepts

Ribotoxins are extremely specific ribonucleases targeted against ribosomes.

Ribotoxins are produced by fungi, some of them entomopathogens.

They show a high degree of structural conservation, including the local arrangement of the active site residues.

Cleavage of a single rRNA phosphodiester bond leads to cell death by inhibiting translation.

Ribotoxins are cyclising RNases because they follow a general acid–base mechanism with production of a 2′,3′‐cyclic intermediate.

Ribotoxins must first enter their target cells to exert their lethal action.

Cell entrance is possible in cells with membranes enriched in acidic phospholipids and altered permeability.

Ribotoxins are optimal candidates to be employed as pest control agents and in antitumour immunotoxins.
A Self‐Powered Sensor Mimicking Slow‐ and Fast‐Adapting Cutaneous Mechanoreceptors
Authors: Chun Kyoung‐Yong , Son Young Jun , Jeon Eun‐Seok , Lee Sehan , Han Chang‐Soo 
Published: February 2018

AbstractHighly efficient human skin systems transmit fast adaptive (FA) and slow adaptive (SA) pulses selectively or consolidatively to the brain for a variety of external stimuli. The integrated analysis of these signals determines how humans perceive external physical stimuli. Here, a self‐powered mechanoreceptor sensor based on an artificial ion‐channel system combined with a piezoelectric film is presented, which can simultaneously implement FA and SA pulses like human skin. This device detects stimuli with high sensitivity and broad frequency band without external power. For the feasibility study, various stimuli are measured or detected. Vital signs such as the heart rate and ballistocardiogram can be measured simultaneously in real time. Also, a variety of stimuli such as the mechanical stress, surface roughness, and contact by a moving object can be distinguished and detected. This opens new scientific fields to realize the somatic cutaneous sensor of the real skin. Moreover, this new sensing scheme inspired by natural sensing structures is able to mimic the five senses of living creatures.
A High‐Performance Optical Memory Array Based on Inhomogeneity of Organic Semiconductors
Authors: Pei Ke , Ren Xiaochen , Zhou Zhiwen , Zhang Zhichao , Ji Xudong , Chan Paddy Kwok Leung 
Published: February 2018

AbstractOrganic optical memory devices keep attracting intensive interests for diverse optoelectronic applications including optical sensors and memories. Here, flexible nonvolatile optical memory devices are developed based on the bis[1]benzothieno[2,3‐d;2′,3′‐d′]naphtho[2,3‐b;6,7‐b′]dithiophene (BBTNDT) organic field‐effect transistors with charge trapping centers induced by the inhomogeneity (nanosprouts) of the organic thin film. The devices exhibit average mobility as high as 7.7 cm2 V−1 s−1, photoresponsivity of 433 A W−1, and long retention time for more than 6 h with a current ratio larger than 106. Compared with the standard floating gate memory transistors, the BBTNDT devices can reduce the fabrication complexity, cost, and time. Based on the reasonable performance of the single device on a rigid substrate, the optical memory transistor is further scaled up to a 16 × 16 active matrix array on a flexible substrate with operating voltage less than 3 V, and it is used to map out 2D optical images. The findings reveal the potentials of utilizing [1]benzothieno[3,2‐b][1]benzothiophene (BTBT) derivatives as organic semiconductors for high‐performance optical memory transistors with a facile structure. A detailed study on the charge trapping mechanism in the derivatives of BTBT materials is also provided, which is closely related to the nanosprouts formed inside the organic active layer.
Superhierarchical Cobalt‐Embedded Nitrogen‐Doped Porous Carbon Nanosheets as Two‐in‐One Hosts for High‐Performance Lithium–Sulfur Batteries
Authors: Liu Shaohong , Li Jia , Yan Xue , Su Quanfei , Lu Yuheng , Qiu Jieshan , Wang Zhiyu , Lin Xidong , Huang Junlong , Liu Ruliang , Zheng Bingna , Chen Luyi , Fu Ruowen , Wu Dingcai 
Published: February 2018

AbstractLithium–sulfur (Li–S) batteries, based on the redox reaction between elemental sulfur and lithium metal, have attracted great interest because of their inherently high theoretical energy density. However, the severe polysulfide shuttle effect and sluggish reaction kinetics in sulfur cathodes, as well as dendrite growth in lithium‐metal anodes are great obstacles for their practical application. Herein, a two‐in‐one approach with superhierarchical cobalt‐embedded nitrogen‐doped porous carbon nanosheets (Co/N‐PCNSs) as stable hosts for both elemental sulfur and metallic lithium to improve their performance simultaneously is reported. Experimental and theoretical results reveal that stable Co nanoparticles, elaborately encapsulated by N‐doped graphitic carbon, can work synergistically with N heteroatoms to reserve the soluble polysulfides and promote the redox reaction kinetics of sulfur cathodes. Moreover, the high‐surface‐area pore structure and the Co‐enhanced lithiophilic N heteroatoms in Co/N‐PCNSs can regulate metallic lithium plating and successfully suppress lithium dendrite growth in the anodes. As a result, a full lithium–sulfur cell constructed with Co/N‐PCNSs as two‐in‐one hosts demonstrates excellent capacity retention with stable Coulombic efficiency.
Geometrically Mediated Topographic Steering of Neurite Behaviors and Network Formation
Authors: Kuddannaya Shreyas , Tong Chong Swee , Fan Yantao , Zhang Yilei 
Published: February 2018

AbstractThe relationship between different mechanoregulatory factors and mechanisms by which neuronal development is regulated by diverse biophysical cues in the immediate vicinity of neural cells remains sparsely understood. Considering the extreme physical complexity of neuronal niches, it is imperative to look beyond the chemical cues for a holistic understanding in these lines. Here the role of geometrically diverse physical microcues is studied in morphologically regulating neurite branching, direction, growth, and network formation in nascent primary cortical neurons on a simple cytocompatible interface. The results indicate distinct differences in neurite branching, microgap sensing, and path‐finding tendencies in response to the underlying angled/curved cues on the micropatterned interface. While the microtraps along curved cues promote higher branching, the highly angled cues promote relatively lower branching with higher neurite lengths. In this study specific morphological changes induced by these cues on the collective conformity, branching, and mean length of neurites in both isolated neurons and neurons in networks are investigated. Finally, a model is proposed to study mechanoregulation of isolated neurons and neuronal networks in response to diverse physical cues. Overall, this platform aims to propel efficient morphological modulation for the study of neurodevelopmental anomalies or physical guidance inspired repair strategies.
Handedness in gestural and manipulative actions in male hunter‐gatherer Aka pygmies from Central African Republic
Authors: Robira Benjamin , Pouydebat Emmanuelle , San‐Galli Aurore , Meulman Ellen J. M. , Aubaile Françoise , Breuer Thomas , Masi Shelly 
Published: February 2018

AbstractObjectivesAll human populations display a right‐biased handedness. Nonetheless, if studies on western populations are plenty, investigations of traditional populations living at subsistence levels are rare. Yet, understanding the geographical variation of phenotypes of handedness is crucial for testing evolutionary hypotheses. We aimed to provide a preliminary investigation of factors affecting handedness in 25 Aka pygmies from Central African Republic when spontaneously gesturing or manipulating food/tools (Nactions = 593).Materials and methodsWe recorded spontaneous behaviors and characterized individuals' hand preference using GLMM with descriptive variables as target position, task complexity (unimanual/bimanual), task nature (food/tool manipulation, gesture), and task physical/cognitive constraints (precision or power for manipulative actions and informative content for gestures).ResultsIndividuals were lateralized to the right (93%,N = 15) when manipulating food/tools but not when gesturing. Hand preference was affected by target position but not by task complexity. While nonexplicitly informative gestures were more biased to the right compared to explicitly informative ones, no differences were found within food/tool manipulation (power or precision vs. none).DiscussionAlthough we do not intend to assume generalizable results due to our reduced sample, our observations provide additional information on handedness in a contemporary traditional society. Especially, the study mainly evidenced considerable cultural effects in gestures while also supporting theories considering active tool manipulation as one of the overriding factor in human handedness evolution.
Gold Nanoclusters for Targeting Methicillin‐Resistant Staphylococcus aureus In Vivo
Authors: Xie Yangzhouyun , Liu Yong , Yang Junchuan , Liu Yuan , Hu Fupin , Zhu Kui , Jiang Xingyu 
Published: February 2018

AbstractWidespread multidrug resistance caused by the abuse of antibiotics calls for novel strategies and materials. Gold nanoclusters (AuNCs) are scarcely explored for combating multidrug‐resistant (MDR) bacteria in vivo. We herein synthesized a novel class of AuNCs, namely quaternary ammonium (QA) capped AuNCs (QA‐AuNCs) as potent antibiotics selectively targeting MDR Gram‐positive bacteria, including methicillin‐resistant Staphylococcus aureus (MRSA) and vancomycin‐resistant Enterococci (VRE), in vivo. QA‐AuNCs kill bacteria through a combined physicochemical mechanism, and show excellent therapeutic effects in both a skin infection model and a bacteremia model induced by MRSA. In addition, owing to their intense fluorescence, QA‐AuNCs can be used for the discrimination of live/dead bacteria and bacteria counting, suggesting their potential for clinical theranostics.
Halogen Bond Catalyzed Bromocarbocyclization
Authors: Chan Yuk‐Cheung , Yeung Ying‐Yeung 
Published: February 2018

AbstractA halogen bond catalyzed bromo‐carbocyclization of N‐cinnamyl sulfonamides and O‐cinnamyl phenyl ethers has been developed. N‐methyl 4‐iodopyridinium triflate is used as the halogen‐bonding organocatalyst and the reaction is highly chemoselective. This report represents the first proof‐of‐concept for halogen‐bonding organocatalyst‐promoted electrophilic halogenation. Mechanistic study suggests the autocatalytic nature of this reaction.
Direct Palladium‐Catalyzed β‐Arylation of Lactams
Authors: Chen Ming , Liu Feipeng , Dong Guangbin 
Published: February 2018

AbstractA direct and catalytic method is reported here for β‐arylation of N‐protected lactams with simple aryl iodides. The transformation is enabled by merging soft enolization of lactams, palladium‐catalyzed desaturation, Ar−X bond activation, and aryl conjugate addition. The reaction is operated under mild reaction conditions, is scalable, and is chemoselective. Application of this method to concise syntheses of pharmaceutically relevant compounds is demonstrated.
Layered Nano‐TiO2 Based Treatments for the Maintenance of Natural Stones in Historical Architecture
Authors: Gherardi Francesca , Goidanich Sara , Dal Santo Vladimiro , Toniolo Lucia 
Published: February 2018

AbstractLayered treatments of natural stones based on dispersions of experimental nano‐TiO2 and commercial TEOS showing photocatalytic and self‐cleaning properties were set up and tested. To enhance nano‐TiO2 efficacy, a surface pre‐treatment with tetraethyl orthosilicate was proposed to avoid the penetration of NPs into the crystalline porous substrates and to improve their adhesion to the stone. Two treatment applications (wet‐on‐wet and wet‐on‐dry) were compared, showing different results. A strong interaction Si−O−Ti was the key factor for the successful treatment, leaving the band gap and relevant properties of nano‐TiO2 unaltered. The layered treatments were tested on a porous calcarenite (Noto stone) and a very compact marble (Carrara marble). The combined SiO2‐nano‐TiO2 treatments can find application in suitable cases where a surface consolidation is needed, ensuring a depolluting and self‐cleaning durable activity.
Probing Substrate Diffusion in Interstitial MOF Chemistry with Kinetic Isotope Effects
Authors: Wang Chen‐Hao , Das Anuvab , Gao Wen‐Yang , Powers David C. 
Published: February 2018

AbstractMetal–organic frameworks (MOFs) have garnered substantial interest as platforms for site‐isolated catalysis. Efficient diffusion of small‐molecule substrates to interstitial lattice‐confined catalyst sites is critical to leveraging unique opportunities of these materials as catalysts. Understanding the rates of substrate diffusion in MOFs is challenging, and few in situ chemical tools are available to evaluate substrate diffusion during interstitial MOF chemistry. Herein, we demonstrate nitrogen atom transfer (NAT) from a lattice‐confined Ru2 nitride to toluene to generate benzylamine. We use the comparison of the intramolecular deuterium kinetic isotope effect (KIE), determined for amination of a partially deuterated substrate, with the intermolecular KIE, determined by competitive amination of a mixture of perdeuterated and undeuterated substrates, to establish the relative rates of substrate diffusion and interstitial chemistry. We anticipate that the developed KIE‐based experiments will contribute to the development of porous materials for group‐transfer catalysis.
Effects of peroxide and phenolic cure systems on characteristics of the filled ethylene–propylene–diene monomer rubber (EPDM)
Authors: Imanifar Marzieh , Ostad Movahed Saeed , Ahmadpour Ali 
Published: February 2018

ABSTRACTThe effects of three curing systems, peroxide, peroxide–phenolic combination, and phenolic on selected properties of cured carbon black‐filled ethylene–propylene–diene monomer rubber (EPDM) were investigated. The cured rubbers immersed in hot amine solution to evaluate their suitability for seal and gasket industry at elevated temperature and amine environments. These tests were essential for evaluating the durability of the gasket in a gas refinery. The Fourier transform infrared spectroscopy spectrums revealed that the phenolic crosslink was constructed between rubber macromolecules during the curing process. The changing curing system from peroxide to peroxide–phenolic and phenolic increased the glass transition temperature of the filled cured rubbers between 3 and 5 °C. There was not any significant difference between thermogravimetric analysis thermographs of the selected cured rubbers with various cure systems and the residues ranged between 45% and 47%. Unlike of peroxide curing system, a dual phase was observed from scanning electron microscopy micrographs for peroxide–phenolic and phenolic cure systems. The phenolic cure system was not beneficial for rubber curing although, it reduced scorch time of the curing process. For the most studied mechanical properties, phenolic cure system deteriorated mechanical properties for both, aged and unaged cured rubbers. Increasing the amount of diene monomer in EPDM structure was beneficial for phenolic rubber cure system. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46213.
Facile fabrication of polyaniline/polypyrrole copolymer nanofibers with a rough surface and their electrorheological activities
Authors: He Kai , Qin Cheng , Wen Qingkun , Wang Chengwei , Wang Baoxiang , Yu Shoushan , Hao Chuncheng , Chen Kezheng 
Published: February 2018

ABSTRACTHierarchical polyaniline/polypyrrole (PANI/PPy) copolymer nanofiber was prepared via a two‐step method and adopted as dispersing materials for electrorheological (ER) fluids. The first step was used to synthesize PANI nanofibers by a rapid mixing method. Subsequently, the PANI/PPy copolymer nanofibers with a rough surface were obtained using an in situ polymerization method continuously. The morphology of the resultant PANI/PPy copolymer nanofibers can be controlled by varying the amount of Py monomer in the secondary in situ polymerization method. The rough surface of PANI/PPy copolymer nanofibers were confirmed by scanning electron microscopy and transmission electron microscopy. The diameter of PANI/PPy nanofiber is within the range 100–200 nm. The obtained PANI/PPy copolymer particles all exhibit amorphous structure through X‐ray diffraction measurement. We also demonstrated that the hierarchical PANI/PPy copolymer nanofibers exhibited characteristic ER behaviors, which were investigated using a Haake rotational rheometer at various electric field strengths. The ER efficiency e for PANI‐1mLPPy and PANI‐2mLPPy ER fluids at shear rate 0.1 s−1 is 36.6 and 28.5 under electric field strength E = 3 kV/mm, respectively. Low leaking current density is observed even at high electric field strength and wide plateau region appeared, which show a strong ER activity for the PANI/PPy composite nanofibers. The results also indicate that the PANI/PPy composite particles have distinctly enhanced ER effect compared with the pure PANI and PPy particles under electric stimuli. The significantly improved ER property of PANI/PPy‐based ER fluid is ascribed to the enhanced interfacial polarization. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46289.