bluuebunny/crossref_metadata_2025_split huggingface dataset:
New ionic liquid increase the catalytic efficiency of recombinant Escherichia coli cells‐mediated asymmetric reduction
Authors: Li Jun , Fan Miaoliang , Zhang Rongjin , Tian Zheyu , Zeng Jing , Song Yinan , Du Wenting 
Published: July 2018

ABSTRACTBackgroundIonic liquids (ILs) have advantages in terms of flexible structure and composition for the whole cell mediated biocatalytic reaction. However, the lack of design strategy for ILs has hampered the development of biocatalysis in non‐aqueous medium. In the present study, to establish an efficient reaction system to obtain vital chiral compounds, a novel IL was designed by combining the superior characteristics of quaternary ammonium‐ and dialkyl‐based cationic surfactant IL to enhance the recombinant Escherichia coli cells‐catalyzed bioreduction efficiency.Results[HOEtN1,1,1][BF4] was synthesized and showed excellent characteristics of low toxicity to the biocatalyst, reduced toxicity of substrate to the microbial cells and moderate increase of cell membrane permeability. In the [HOEtN1,1,1][BF4]‐ containing reaction system, some valuable factors involved in the biocatalytic reduction of ethyl 4‐chloro‐3‐oxobutanoate to ethyl (S)‐4‐chloro‐3‐hydroxybutanoate were found to be: 2.5% (w/v) [HOEtN1,1,1][BF4], 20% (v/v) isopropanol, 3 M COBE, pH 7.0, 30 °C, reacted for 16 h. A yield of 96.7% was obtained under the optimum conditions with above 99% enantiomeric excess value, and the proposed bioprocess was also successfully scaled up to a 5 L fermentor with a yield of 90.7%.ConclusionThe developed IL [HOEtN1,1,1][BF4] is a promising solvent for enhancing the efficiency of model bioreduction. It was also evaluated for broadening its application to the biosynthesis of (R)‐[3,5‐bis(trifluoromethyl)phenyl] ethanol catalyzed by recombinant Escherichia coli, with remarkable success. © 2018 Society of Chemical Industry
T‐Hg2+‐T‐based satellite structured surface enhanced Raman scattering sensor for Hg2+ detection
Authors: Sun Zhenli , Du Jingjing , He Kebin , Jing Chuanyong 
Published: July 2018

AbstractMercury ion (Hg2+) exposure is a threat to human health. We report a plasmonic core‐satellite Fe3O4@SiO2‐Au (FA) hetero nanostructure for Hg2+ detection using surface enhanced Raman scattering based on the T‐Hg2+‐T strategy. The FA nanostructure was functionalized by a DNA aptamer, which was designed with Cy5 at the 5′ end, and used as a Raman reporter to specifically bind to Hg2+ ions. In the presence of Hg2+, DNA formed a hairpin structure, bringing Cy5 close to the FA hotspots region, thus generating an enhanced Raman signal. The T‐Hg2+‐T complex formed the basis for the determination of trace Hg2+ with a detection limit lower than 5 × 10−9 M, and the influence of other metal ions was found to be negligible. With high selectivity, sensitivity, and recyclability, this FA‐DNA surface enhanced Raman scattering platform is a promising tool for field monitoring of Hg2+ ions.
Temperature‐dependent absorption lines observation in Raman spectra of SmFe3 (BO3)4 ferroborate
Authors: Moshkina Evgeniya , Gudim Irina , Temerov Vladislav , Krylov Alexander 
Published: July 2018

AbstractThe paper demonstrates possibilities of observation and thermal dependency study of the absorption lines as a co‐product of Raman spectroscopy study in SmFe3 (BO3)4 ferroborate. Raman spectra of the ferroborate were studied in a wide temperature range (T = 10÷300 K). Temperature‐dependent absorption lines sensitive to the magnetic phase transition have been observed in Raman spectra at two spectral ranges.
An optimized 4‐day diet meal plan for ‘Lunar Palace 1’
Authors: Fu Yuming , Guo Rong , Liu Hong 
Published: July 2018

AbstractBACKGROUNDBioregenerative life support systems (BLSS) provide self‐sufficient food ingredients to support long‐term manned missions. It is crucial to transform raw food ingredients that are regenerated in situ in BLSS into nutritional and delectable meals for spacecraft crews. It is in our interest to develop a dietary menu with Chinese characteristics that comprises biomass produced in situ with BLSS regenerated ingredients.RESULTSHere we report an optimized Chinese 4‐day diet meal plan for ‘Lunar Palace 1’ that is nutritionally balanced and highly acceptable. The 2900 cal diet menu not only meets the requirements of a balanced diet for crews but also exceeds the recommended levels for most nutrients. Specifically, daily fresh food consumption in our meal plan is 1267 g day−1, of which 78% is provided by crops and insects regenerated in situ in the BLSS. The meal plan is highly favored by Chinese crews, with acceptability as high as 7.8–8.2 on a 9‐point hedonic scale. We further confirmed that our meal plan satisfies crews' basic nutritional needs through a 105‐day closed habitation experiment.CONCLUSIONIn brief, the findings provide new insights for dietary meal plan design in future long‐term manned missions. © 2018 Society of Chemical Industry
Achieving low‐carbon cattle ranching in the Amazon: ‘Pasture sudden death’ as a window of opportunity
Authors: Silva Marraiane A. , Lima Mendelson , Silva Junior Carlos A. , Costa Gerlane M. , Peres Carlos A. 
Published: July 2018

AbstractLivestock farming is the key sector that can most contribute to low‐carbon agriculture in the Amazon, the region of Brazil that stands most to gain from land‐use intensification and most to lose from further primary habitat loss. Cattle pastures affected by the ‘sudden death’ syndrome, which has decimated exotic grass pastures across seven Amazonian states, have forced cattle ranchers to begin renewing their grazing lands. Vast areas of pasture die‐off create an opportunity to catalyse livestock intensification through public policies. More productive livestock husbandry results in avoided deforestation, mitigation of methane emissions from enteric digestion, and the release of vast previously deforested areas to either more intensive agriculture or forest restoration. This, however, comes with a cautionary note as the much debated promising paradigm of agricultural intensification remains largely untested as a land‐sparing strategy across the humid tropics. Well‐designed government subsidies will, therefore, be required to ensure that thousands of landowners can take advantage of this opportunity with minimal environmental side effects.
Recent evolution of an ice‐cored moraine at the Gentianes Pass, Valais Alps, Switzerland
Authors: Ravanel Ludovic , Duvillard Pierre‐Allain , Jaboyedoff Michel , Lambiel Christophe 
Published: July 2018

AbstractLateral moraines located in permafrost environments often preserve large amounts of both glacier and periglacial ice. To understand how ice‐cored moraines located in high alpine environments evolve in a context of both glacier retreat and permafrost degradation, we performed 11 terrestrial laser‐scanning measurement campaigns between 2007 and 2014 on a highly anthropogenic overprinted moraine prone to instability. Resulting comparison of the subsequent 3D models allowed to qualitatively and quantitatively analyze the morphological evolution of the moraine. The comparisons indicate a very high geomorphic activity of the moraine including large areas affected by downslope movements of blocks and 10 landslides with a volume between 24 ± 1 and 1,138 ± 47 m3. Data also indicated a very strong ice melt with a loss of ice thickness locally reaching 17.7 m at the foot of the moraine. These results, compared with resistivity and thermal measurements of the ground, suggest the combined role of ice loss at the foot of the moraine and the permafrost activity/warming in triggering these processes.
Influence of Acrylic Polymers Stereoregularity on Interface Interactions in Model Thin Film Systems
Authors: Marzec Mateusz M. , Awsiuk Kamil , Daąbczyński Paweł , Rysz Jakub , Budkowski Andrzej , Bernasik Andrzej 
Published: July 2018

AbstractThe origin and formation of the dipole moment at the interface of metal electrode and thin organic film is crucial for the fabrication of high‐performance organic electronic devices. In this work, model polymer multilayer systems are studied in which interfaces are modified heterogeneously with thiol‐based self‐assembled monolayers (SAM). Due to the presence of polar terminal group (‐COOH) in SAM and polar pendant groups (‐COOH, ‐C(O)OCH3) within studied polymers, it is pointed out that the resultant interface energetics differ from the expected ones as one would expect from the chemical character of the self‐assembled molecules used to tune junction properties. This is discussed in terms of inter‐association and depolarization effects between polymer and thiol modified substrate. The presented model systems may serve as an interaction reference for SAMs and semiconducting polymers containing similar moieties, utilized for the fabrication of organic electronic devices.
The Role of Selectively Located Commercial Graphene Nanoplatelets in the Electrical Properties, Morphology, and Stability of EVA/LLDPE Blends
Authors: Kurusu Rafael S. , Helal Emna , Moghimian Nima , David Eric , Demarquette Nicole 
Published: July 2018

AbstractGraphene nanoplatelets (GN) produced on a large scale by mechanochemical exfoliation of graphite are incorporated in a co‐continuous ethylene‐vinyl acetate/linear low‐density polyethylene (EVA/LLDPE) blend. Two different processing routes are chosen to selectively place GN in the EVA phase or force its migration to the EVA/LLDPE interface. The results show a drastic decrease in the electrical percolation threshold when the blends are compared to the respective single‐polymer composites. Even with the presence of agglomerates, GN particles are able to migrate to the blend interface and stabilize the morphology and hence the electrical properties. Annealing the insulating samples at processing temperatures causes a drastic increase in conductivity due to continued GN migration and blend morphology coarsening. Semi‐conductive samples, in which a more robust GN network is already established during processing, present no change in morphology but a slight increase in conductivity during annealing. The mechanical performance of the materials is also evaluated and some of the blends with GN present similar elongation at break as pure EVA, but with increased tensile modulus and tensile strength. The electrical performance at different working temperatures shows that the EVA/LLDPE/GN composites are good candidates to act as a semi‐conductive screen material in power cables or as anti‐static materials in electronic devices.
An 17O NMR study of diamagnetic and paramagnetic lanthanide‐tris(oxydiacetate) complexes in aqueous solution
Authors: Fusaro Luca 
Published: July 2018

Abstract17O‐enriched complexes between oxydiacetate ligand and several diamagnetic and paramagnetic lanthanide(III) metal ions (Ln) were investigated by solution‐state 17O NMR spectroscopy. The bound‐state signals of chelating (Oin) and nonchelating (Oout) oxygen atoms of the carboxylate groups were observed for all the samples investigated. The data indicate that the 17O line width is dominated by contributions from both quadrupole relaxation and chemical exchange in the case of Pr and Nd complexes. Dissection of the chemical shift induced by metal ions on Oin into Fermi contact and pseudocontact contributions was performed , and the hyperfine coupling constant (A/ℏ) was estimated. No evidence of structural changes within the series was detected.
Recursive integral method with Cayley transformation
Authors: Huang R. , Sun J. , Yang C. 
Published: July 2018

SummaryThe recently developed RIM (recursive integral method) finds eigenvalues in a region of the complex plane. It computes an indicator to test if the region contains eigenvalues using an approximate spectral projection. If the indicator shows that the region contains eigenvalues, it is subdivided into smaller regions, which are then recursively tested and subdivided until any eigenvalues are isolated to a specified precision. We propose an enhancement to RIM that uses Cayley transformations and Arnoldi's method to greatly decrease the number of factorizations required to solve the linear systems that arise from a discretized contour integral to compute the indicator, which substantially reduces the computational cost. We demonstrate the efficacy of our method with numerical examples and compare with the implicitly restarted Arnoldi method, as implemented in eigs in MATLAB.
Improved mechanical properties of poly (vinyl alcohol) films with glycerol plasticizer by uniaxial drawing
Authors: Tian Huafeng , Yuan Li , Zhou Dan , Niu Junyi , Cong Hengjiang , Xiang Aimin 
Published: July 2018

In this work, the uniaxial stretching poly (vinyl alcohol) (PVA) films with glycerol as plasticizer were prepared to explore the influence of drawing temperature and drawing ratio. The structure and property were investigated with scanning electron microscope, wide‐angle X‐ray diffraction, X‐ray diffraction, differential scanning calorimetry, mechanical tests, etc. With the increase of stretching temperature, the melting and crystallization temperatures increased. The tensile strength and Young modulus of glycerol/PVA films increased first and then decreased; when the temperature was 80°C, the tensile strength and Young modulus reached to maximum values of 197.2 and 470 MPa, respectively. In addition, with the increase of draw ratio, the orientation degree of the PVA molecular chains increased, indicating the improved regularity of molecular chains. When the PVA films were stretched to 4 times, the tensile strength and Young modulus of the films reached 162 and 143 MPa, respectively, which were 4 and 1.3 times compared with those of unoriented films. These environmentally friendly PVA films with excellent mechanical properties would find wide applications in the industry such as packaging, coating, etc.
Effect of European Medicines Agency's restrictions on trimetazidine utilization in Portugal
Authors: Pinto Daniel , Silva Ana , Heleno Bruno , Rodrigues David Silvério , Santos Isabel , Caetano Pedro A. 
Published: July 2018

AbstractPurposeFollowing safety concerns regarding trimetazidine, the European Medicines Agency (EMA) recommended restrictions on its use. Our objective was to determine the impact of regulatory actions on trimetazidine utilization in Portugal.MethodsRetrospective interrupted time‐series analysis of monthly ambulatory pharmacy reimbursement records for the Portuguese National Health Service between January 2006 and December 2015. Regulatory actions were identified by searching the EMA, Portuguese Medicines Authority, and European Commission's websites. Concurrent factors in the same period were also identified. The main outcome was the dispensing of trimetazidine‐containing products per month in Portugal.ResultsTwo interruption periods were defined in the series: May 2011, when EMA announced it would review trimetazidine safety, and June 2012 to January 2013, when EMA announced it had reached a final opinion recommending restrictions; the European Commission approved EMA's recommendation; the Portuguese Medicines Authority issued safety alerts, changed the summary of product characteristics, and approved a direct health‐care professional letter; and a regional bulletin was issued.Interruption 1 had no effect on trimetazidine use, but interruption 2 resulted in decreases in level and trend—from 8.3 million defined daily doses in 2010 to 2.8 million in 2015. After interruption 2, trimetazidine use tended towards a lower steady state.ConclusionsThere was a significant decrease in trimetazidine use in Portugal following a complex intervention that included safety alerts, changes to the summary of product characteristics, a direct health‐care professional letter, and a regional drug bulletin. No effect was seen when EMA announced its review of trimetazidine safety.
The Relative Risk of Achilles Tendon Injury in Patients Taking Quinolones
Authors: Jupiter Daniel C. , Fang Xiao , Ashmore Zachary , Shibuya Naohiro , Mehta Hemalkumar B. 
Published: July 2018

ObjectiveTo examine the association between quinolone use and Achilles tendon injury, comparing well‐matched cohorts of users of quinolone and nonquinolone antibiotics, and well‐matched cohorts of quinolone users and patients not using any nonquinolone antibiotics.Patients and MethodsThis retrospective cohort study used Clinformatics data from 2008–2014. Using the propensity score, we matched quinolone users with other antibiotic users and quinolone users with nonusers. The primary outcome was Achilles tendon injury within 6 months. Bivariate analyses determined risk factors for Achilles tendon injury, and conditional logistic regression assessed the impact of quinolone use on these injuries.ResultsA total of 716,522 fluoroquinolone users were matched with other antibiotic users, and 645,034 fluoroquinolone users were matched with nonusers. Rates of Achilles tendon injury were less than 0.5% in all groups. Quinolone use increased the risk of Achilles tendon injury compared with other antibiotic users (odds ratio [OR] 1.24, 95% confidence interval [CI] 1.17–1.31) and nonusers (OR 1.54, 95% CI 1.44–1.64). Interaction with age did not significantly impact the relationship between quinolone use and Achilles injury; however, older quinolone users had a slightly higher relative risk of injury than nonusers versus younger patients. Furthermore, the youngest group of patients had similarly elevated relative risk for injury with quinolone use as did the elderly.ConclusionAlthough quinolone use increases the risk of Achilles tendon injury, the absolute risk increase is minimal, especially when compared with similar morbidity patients taking other nonquinolone antibiotics. In relatively healthy populations, such as the one studied here, quinolone use may not make a clinically significant contribution to risk of Achilles tendon injury, at any age range, among those in need of such drugs.
Chitosan nanocomposite films incorporating cellulose nanocrystals and grape pomace extracts
Authors: Xu Yixiang , Willis Shakeyla , Jordan Krystle , Sismour Edward 
Published: July 2018

Chitosan nanocomposite films incorporating grape pomace extract (GPE), either Cabernet Franc (CF; a red variety) or Viognier (a white variety), and cellulose nanocrystal (CNC) were prepared using a solvent casting method. Mechanical properties, water vapour permeability, color and opacity, crystalline structure, thermal properties, total phenolic content, and antioxidant activity of the films were characterized. Incorporating CNC alone significantly (P < .05) increased tensile strength of the films and decreased their percent elongation at break and water vapour permeability. Grape pomace extract had an opposite effect on mechanical properties by decreasing tensile strength but increasing percent elongation at break. Film color was mainly influenced by the presence and type of GPE. Films containing CF extract exhibited the darkest appearance with increased reddish and bluish hues. Addition of CNC significantly increased film opacity and the alignment of chitosan chains, while the effect of GPE was not significant. Thermal analysis showed that chitosan and CNC were partially miscible and that the addition of CNC did not significantly change decomposition temperature of the films. Incorporation of GPE significantly (P < .05) increase total phenolic content and antioxidant activity. Films containing CF had higher DPPH• radical scavenging capacity than their counterparts with Viognier. Film incorporating both CNC and CF shows greater potential for food packaging application because of a combination of improved physical properties and high antioxidant activity.
Ion formation in droplet‐assisted ionization
Authors: Apsokardu Michael J. , Kerecman Devan E. , Johnston Murray V. 
Published: July 2018

RationaleIn droplet‐assisted ionization (DAI), intact molecular ions are generated from molecules in aerosol droplets by passing the droplets through a temperature‐controlled capillary inlet. Ion formation is explored through the effects of analyte mass flow, droplet solvent composition, and capillary temperature on ion signal intensity.MethodsA Waters SYNAPT G2‐S is adapted for DAI by reconfiguring the inlet with a temperature‐controlled capillary. Droplets are generated by atomization of a solution containing analyte and then sampled through the inlet. If desired, solvent can be removed from the droplets prior to analysis by sending the aerosol through a series of diffusion dryers. Size distributions of the dried aerosols allow the mass flow of analyte into the inlet to be determined.ResultsAnalyte signal intensities are orders of magnitude higher from droplets containing a protic solvent (water) than an aprotic solvent (acetonitrile). The highest signal intensities for DAI are obtained with inlet temperatures above 500°C, though the optimum temperature is analyte dependent. At elevated temperatures, droplets are thought to undergo rapid solvent evaporation and bursting to produce ions. The lowest signal intensities are generally obtained in the 100–350°C range, where slow solvent evaporation is thought to inhibit ion formation. As the temperature decreases from 100°C down to 25°C, the signal intensity increases significantly. When 3‐nitrobenzonitrile, a common matrix for solid‐state matrix‐assisted ionization (MAI), is added to droplets consisting of 50/50 v/v water and acetonitrile, the matrix enhances ion formation to produce a signal intensity comparable to DAI in 100% water.ConclusionsThe results are consistent with other inlet ionization techniques, suggesting that similar ion formation mechanisms are operative. Optimized ion yields (the combined effects of ionization probability and ion transmission) for DAI are currently in the 10−5 to 10−6 range, which is sufficient for many aerosol applications.
Weaver: Hexapod robot for autonomous navigation on unstructured terrain
Authors: Bjelonic Marko , Kottege Navinda , Homberger Timon , Borges Paulo , Beckerle Philipp , Chli Margarita 
Published: July 2018

AbstractLegged robots are an efficient alternative for navigation in challenging terrain. In this paper we describe Weaver, a six‐legged robot that is designed to perform autonomous navigation in unstructured terrain. It uses stereo vision and proprioceptive sensing based terrain perception for adaptive control while using visual‐inertial odometry for autonomous waypoint‐based navigation. Terrain perception generates a minimal representation of the traversed environment in terms of roughness and step height. This reduces the complexity of the terrain model significantly, enabling the robot to feed back information about the environment into its controller. Furthermore, we combine exteroceptive and proprioceptive sensing to enhance the terrain perception capabilities, especially in situations in which the stereo camera is not able to generate an accurate representation of the environment. The adaptation approach described also exploits the unique properties of legged robots by adapting the virtual stiffness, stride frequency, and stride height. Weaver's unique leg design with five joints per leg improves locomotion on high gradient slopes, and this novel configuration is further analyzed. Using these approaches, we present an experimental evaluation of this fully self‐contained hexapod performing autonomous navigation on a multiterrain testbed and in outdoor terrain.
K3Bi2Cl5O2(SO4)2: A Novel Pentanary Chloride Oxide Sulfate
Authors: Lu Zhen‐Tao , Chi Yang , Xue Huai‐Guo , Guo Sheng‐Ping 
Published: July 2018

AbstractReported are the synthesis, crystal structure and electronic structure of K3Bi2Cl5O2(SO4)2, which is a novel pentanary chloride oxide sulfate containing three types of anions, Cl–, O2–, and (SO4)2– by using a solution method. It crystallizes in the triclinic space group P
, and the structure features layers built by (BiO5Cl3)8– anionic units and (SO4)2– tetrahedra with K+ ions insertion between layers as counter ions. The band gap of K3Bi2Cl5O2(SO4)2 was determined to be 3.62(2) eV and its electronic structure was also investigated to compare with the experimental results.