bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methylation of the N‐terminal histidine protects a lytic polysaccharide monooxygenase from auto‐oxidative inactivation
Authors: Petrović Dejan M. , Bissaro Bastien , Chylenski Piotr , Skaugen Morten , Sørlie Morten , Jensen Marianne S. , Aachmann Finn L. , Courtade Gaston , Várnai Anikó , Eijsink Vincent G.H. 
Published: July 2018

AbstractThe catalytically crucial N‐terminal histidine (His1) of fungal lytic polysaccharide monooxygenases (LPMOs) is post‐translationally modified to carry a methylation. The functional role of this methylation remains unknown. We have carried out an in‐depth functional comparison of two variants of a family AA9 LPMO from Thermoascus aurantiacus (TaLPMO9A), one with, and one without the methylation on His1. Various activity assays showed that the two enzyme variants are identical in terms of substrate preferences, cleavage specificities and the ability to activate molecular oxygen. During the course of this work, new functional features of TaLPMO9A were discovered, in particular the ability to cleave xyloglucan, and these features were identical for both variants. Using a variety of techniques, we further found that methylation has minimal effects on the pKa of His1, the affinity for copper and the redox potential of bound copper. The two LPMOs did, however, show clear differences in their resistance against oxidative damage. Studies with added hydrogen peroxide confirmed recent claims that low concentrations of H2O2 boost LPMO activity, whereas excess H2O2 leads to LPMO inactivation. The methylated variant of TaLPMO9A, produced in Aspergillus oryzae, was more resistant to excess H2O2 and showed better process performance when using conditions that promote generation of reactive‐oxygen species. LPMOs need to protect themselves from reactive oxygen species generated in their active sites and this study shows that methylation of the fully conserved N‐terminal histidine provides such protection.
New application of direct analysis in real time high‐resolution mass spectrometry for the untargeted analysis of fresh and aged secondary organic aerosols generated from monoterpenes
Authors: Schramm Sébastien , Zannoni Nora , Gros Valérie , Tillmann Ralf , Kiendler‐Scharr Astrid , Sarda‐Estève Roland , Bridoux Maxime 
Published: July 2018

RationaleSecondary organic aerosols (SOAs) represent a significant portion of total atmospheric aerosols. They are generated by the oxidation of volatile organic compounds (VOCs), and particularly biogenic VOCs (BVOCs). The analysis of such samples is usually performed by targeted methods that often require time‐consuming preparation steps that can induce loss of compounds and/or sample contaminations.MethodsRecently, untargeted methods using high‐resolution mass spectrometry (HRMS) have been successfully employed for a broad characterization of chemicals in SOAs. Herein we propose a new application of the direct analysis in real time (DART) ionization method combined with HRMS to quickly detect several hundred chemicals in SOAs collected on a quartz filter without sample preparation or separation techniques.ResultsThe reproducibility of measurements was good, with several hundred elemental compositions common to three different replicates. The relative standard deviations of the intensities of the chemical families ranged from 6% to 35%, with sufficient sensitivity to allow the unambiguous detection of 4 ng/mm2 of pinic acid. The presence of oligomers and specific tracers was highlighted by MSn (n ≤ 4) experiments, an achievement that is difficult to attain with other ultrahigh‐resolution mass spectrometers. Contributions of this untargeted DART‐HRMS method were illustrated by the analysis of fresh and aged SOAs from different gaseous precursors such as limonene, a β‐pinene/limonene mixture or scots pines emissions.ConclusionsThe results show that it is possible to use DART‐HRMS for the identification of tracers of specific aging reactions, or for the identification of aerosols from specific biogenic precursors.
Enzymatic biodegradation of high molecular weight polymers in the sediment–water interface in the coastal river estuary
Authors: Perliński P. , Mudryk Z. J. 
Published: July 2018

AbstractThe level of activity of eight extracellular hydrolytic enzymes responsible for biodegradation of high molecular weight polymers in the water–sediment interface in the coastal river estuary was determined. The ranking order of the mean enzyme activity rates in the sediment–water interface was as follows: lipase > aminopeptidase > phosphatase > β‐glucosidase > α‐glucosidase > xylanase > chitinase > cellulase. The activity of the studied enzymes differed between various parts of the estuary. Each enzyme had its characteristic horizontal activity profile. Extracellular enzymatic activities were strongly influenced by the season. As a rule, tested enzymes showed their maximum hydrolytic activity during the vegetation period.
Ka and Q band propagation experiments in Toulouse using ASTRA 3B and ALPHASAT satellites
Authors: Boulanger Xavier , Castanet Laurent 
Published: July 2018

SummaryFrom January 2008 to March 2011, ONERA operated in Toulouse, France, a beacon receiver able to collect the 19.7‐GHz beacon signal of the HotBird 6 satellite. In March 2011, the radio frequency chain was modified to be able to receive the 20.2‐GHz ASTRA 3B beacon to benefit from a higher Equivalent Isotropically Radiated Power of the satellite. Since June 2015, a second beacon receiver has been installed and is able to record the 39.4‐GHz beacon signal of the Alphasat satellite. The objective of this paper is to present the results of the first 2 years of measurements (June 2015 to May 2017) of the Q‐band Alphasat propagation experiment in Toulouse, as well as concurrent measurements collected at Ka‐band with ASTRA 3B. First of all, the propagation experiments are briefly described. Second, the results of the statistical analysis are highlighted. Finally, a deep analysis of the performances of the 2 frequency scaling prediction methods recommended in ITU‐R P.618‐13 is performed.
Reaching energy autonomy in a medium‐sized city – three scenarios to model possible future energy developments in the residential building sector
Authors: Dobler Claudia , Pfeifer Dominik , Streicher Wolfgang 
Published: July 2018

AbstractA city energy model was developed to demonstrate possible future trajectories for the residential building sector up until 2050 for the city of Innsbruck in Austria, a medium‐sized city in the Austrian Alps. It examines final and delivered energy, respectively, from a demand side perspective. Three different scenarios are defined to illustrate the range of future developments in the residential building sector (scenario analysis). The base scenario 1 represents a continuation of recent trends (business‐as‐usual). The middle course scenario 2 is characterized by stricter thermal standards for the building envelope and a beginning of withdrawal from fossil fuels from 2031. The target scenario 3 objective is specified as a 50% reduction in delivered energy and a complete transition to renewable energies by 2050. Scenario 3 differs from scenario 2 primarily in the aspect of an earlier implementation date for certain measures, for example, the beginning of the withdrawal from fossil fuels is scheduled for 2021.
Corrosion Protection of Carbon Steel in Circulating Cooling Water by Open‐chain Carboxyethyltin and Transition Metal Co‐functionalized Tungstogermanates
Authors: Sang Xiaojing , Wang Zhixin , Li Jiansheng , Wang Haidan , Su Fang , Liu Zhaobin , Zhang Lancui , Zhu Zaiming 
Published: July 2018

AbstractOpen‐chain carboxyethyltin and transition metal (TM) co‐decorated double armed type polyoxometalates (POMs) [C(NH2)3]10H2[(TM)2(SnCH2CH2COO)2(B‐α‐GeW9O34)2]•nH2O (abbreviated as GeW9‐TM‐SnR‐COO, TM=Mn, Cu, Zn) were firstly applied as corrosion inhibitors for carbon steel in circulating cooling water, and the corrosion inhibition abilities of them and their parent POMs Na12[(TM)4(H2O)2(GeW9O34)2]•nH2O (abbreviated as GeW9‐TM, TM=Mn, Cu, Zn) were evaluated by gravimetric method and electrochemical impedance spectroscopy. The morphology, composition and element oxidation state of metallic surface film were characterized by scanning electron microscopy/energy dispersive X‐ray spectroscopy (SEM/EDX) and X‐ray photoelectron spectroscopy (XPS) technologies. Compared with GeW9‐TM, GeW9‐TM‐SnR‐COO organic‐inorganic hybrids improved corrosion resistance of carbon steel. Additionally, GeW9‐TM‐SnR‐COO showed good synergistic effect with polyhydric alcohol phosphate ester (PAPE) and sulfonate copolymer (AMPS), and the maximum inhibition efficiency is up to 97% for GeW9‐Zn‐SnR‐COO+PAPE+AMPS composite.
Synthesis of Functionalized Phenathridine‐6‐carbonitriles via Copper‐catalyzed Annulation of Vinyl Azides and NaN3 in the Presence of PhI(OAc)2
Authors: Zhou Bingwei , Zheng Limeng , Xu Zheng , Jin Hongwei , Wu Qingan , Li Ting , Liu Yunkui 
Published: July 2018

AbstractA convenient and efficient protocol for the synthesis of phenanthridine‐6‐carbonitriles has been successfully developed involving a copper(II)‐catalyzed tandem annulation of vinyl azides and NaN3 in the presence of PhI(OAc)2. A variety of functionalized phenanthridine‐6‐carbonitriles were synthesized in moderate to good yields under mild reaction conditions. Mechanistic study revealed that a radical pathway might be involved in this annulation reaction.
An Immobilized Enzyme Reactor for Spatiotemporal Control over Reaction Products
Authors: Grant Jennifer , Modica Justin A. , Roll Juliet , Perkovich Paul , Mrksich Milan 
Published: July 2018

AbstractThis paper describes a microfluidic chip wherein the position and order of two immobilized enzymes affects the type and quantity of reaction products in the flowing fluid. Assembly of the chip is based on a self‐assembled monolayer presenting two orthogonal covalent capture ligands that immobilize their respective fusion enzyme. A thiol‐tagged substrate is flowed over a region presenting the first enzyme—which generates a product that is efficiently transferred to the second enzyme—and the second enzyme's product binds to an adjacent thiol capture site on the chip. The amount of the three possible reaction products is quantified directly on the chip using self‐assembled monolayers for matrix‐assisted laser desorption/ionization mass spectrometry, revealing that the same microsystem can be spatiotemporally arranged to produce different products depending on the device design. This work allows for optimizing multistep biochemical transformations in favor of a desired product using a facile reaction and analytical format.
Effective Suppression of Lithium Dendrite Growth Using a Flexible Single‐Ion Conducting Polymer Electrolyte
Authors: Deng Kuirong , Qin Jiaxiang , Wang Shuanjin , Ren Shan , Han Dongmei , Xiao Min , Meng Yuezhong 
Published: July 2018

AbstractA novel single‐ion conducting polymer electrolyte (SIPE) membrane with high lithium‐ion transference number, good mechanical strength, and excellent ionic conductivity is designed and synthesized by facile coupling of lithium bis(allylmalonato) borate (LiBAMB), pentaerythritol tetrakis (2‐mercaptoacetate) (PETMP) and 3,6‐dioxa‐1,8‐octanedithiol (DODT) in an electrospun poly(vinylidienefluoride) (PVDF) supporting membrane via a one‐step photoinitiated in situ thiol–ene click reaction. The structure‐optimized LiBAMB‐PETMP‐DODT (LPD)@PVDF SIPE shows an outstanding ionic conductivity of 1.32 × 10−3 S cm−1 at 25 °C, together with a high lithium‐ion transference number of 0.92 and wide electrochemical window up to 6.0 V. The SIPE exhibits high tensile strength of 7.2 MPa and elongation at break of 269%. Due to these superior performances, the SIPE can suppress lithium dendrite growth, which is confirmed by galvanostatic Li plating/stripping cycling test and analysis of morphology of Li metal electrode surface after cycling test. Li|LPD@PVDF|Li symmetric cell maintains an extremely stable and low overpotential without short circuiting over the 1050 h cycle. The Li|LPD@PVDF|LiFePO4 cell shows excellent rate capacity and outstanding cycle performance compared to cells based on a conventional liquid electrolyte (LE) with Celgard separator. The facile approach of the SIPE provides an effective and promising electrolyte for safe, long‐life, and high‐rate lithium metal batteries.
Wood Derived Composites for High Sensitivity and Wide Linear‐Range Pressure Sensing
Authors: Huang Yan , Chen Yun , Fan Xiangyu , Luo Ningqi , Zhou Shuang , Chen Shih‐Chi , Zhao Ni , Wong Ching Ping 
Published: July 2018

AbstractNatural wood possesses a unique 3D microstructure containing hierarchical interconnected channels along its growth direction. This study reports a facile processing strategy to utilize such structure to fabricate carbon/silicone composite based flexible pressure sensors. The unique contribution of the multichannel structure on the sensor performance is analyzed by comparing the pressure response of the vertically cut and horizontally cut composite structures. The results show that the horizontally cut composite based sensors exhibit much higher sensitivity (10.74 kPa−1) and wider linear region (100 kPa, R2 = 99%), due to their rough surface and largely deformable microstructure. Besides, the sensors also show little hysteresis and good cycle stability. The overall outstanding sensing properties of the sensors allow for accurate continuous measurement of human pulse and respiration, benefiting the real‐time health signal monitoring and disease diagnoses.
A Dual Carbon‐Based Potassium Dual Ion Battery with Robust Comprehensive Performance
Authors: Zhu Jiaojiao , Li Yali , Yang Bingjun , Liu Lingyang , Li Junshuai , Yan Xingbin , He Deyan 
Published: July 2018

AbstractDual carbon‐based potassium dual ion batteries (K‐DCBs) have recently attracted ever‐increasing attention owing to the potential advantages of high performance‐to‐cost ratio, good safety, and environmental friendliness. However, the reported K‐DCBs still cannot simultaneously meet the requirements of high capacity, long cycling stability, and low cost, which are necessary for practical applications. In this study, a K‐DCB with good comprehensive performance including capacity, cycling stability, medium discharge voltage, and energy density is developed by introducing the optimal cathode and anode materials, i.e., KS6 and natural graphite, respectively. An initial capacity of ≈54.6 mAh g−1 and 92.5% capacity retention after 400 cycles can be delivered in a wide voltage window of 2.4–5.4 V at the current density of 100 mA g−1. A high medium discharge voltage around 4.2 V and an energy density up to 158.3 Wh kg−1 are meanwhile delivered by the K‐DCB. In addition, the working mechanism of the devices is understood in detail. It is believed that valuable contributions to the electrochemical performance improvement of the related devices toward practical applications can be provided by this study.
Rechargeable Magnesium Batteries using Conversion‐Type Cathodes: A Perspective and Minireview
Authors: Zhang Zhonghua , Dong Shamu , Cui Zili , Du Aobing , Li Guicun , Cui Guanglei 
Published: July 2018

AbstractRechargeable magnesium (Mg) batteries are one of the potential contenders to replace current Li‐ion batteries to power future electric vehicles with lower cost, higher safety, and extended mileage. To achieve this goal, both high‐voltage intercalation‐type cathodes and high‐capacity conversion‐type cathodes are considered. However, there are still no reports to compare rechargeable Mg batteries with the state‐of‐the art Li‐ion batteries in terms of their overall performance. Also, potential cathode materials to deliver higher energy density in rechargeable Mg batteries are rarely summarized. Here, the practically accessible energy characteristics of Mg‐based and Li‐ion chemistry are presented and compared using practical cell‐level modeling. Among the reported cathode materials, only sulfur, a typical conversion‐type cathode, is capable of delivering a higher energy density than current lithium‐ion batteries in terms of energy density. Since the electrochemical performance of the conversion‐type cathode is determined by the electrolyte at the current stage, the recent developments of Mg‐ion electrolytes, particularly those with non‐nucleophilic features, are reviewed. The recent advances are then summarized and the future challenges of high‐capacity conversion‐type cathodes for rechargeable Mg batteries are analyzed. The proposed guidelines provide new insights for developing high‐energy‐density Mg batteries.
Direct and simultaneous determination of methionine sulfoxide and pyroglutamic acid impurities in Compound Amino Acid Injection‐18 AA by ion‐pair reversed‐phase HPLC
Authors: Li Li , Qin Yaru , Ma Bingyuan , Cui Hongyan , Qiao Ping , Jiang He , Zhang Ming 
Published: July 2018

AbstractA direct and simultaneous determination of methionine sulfoxide and pyroglutamic acid impurities in Compound Amino Acid Injection‐18 AA by ion‐pair reversed‐phase high‐performance liquid chromatography with ultraviolet detection is described. The separation of both impurities in Compound Amino Acid Injection‐18 AA was accomplished with gradient elution consisting of acetonitrile and 10 mM diammonium hydrogen phosphate buffer (containing 15 mM sodium 1‐heptanesulfonate and obtaining pH 2.3 by addition of phosphoric acid). The limits of detection (μg/mL, S/N = 3:1) and quantification (μg/mL, S/N = 10:1) of methionine sulfoxide and pyroglutamic acid were 0.02 and 0.08, and 0.06 and 0.19, respectively. The linearity was in the range of 0.08–200.20 μg/mL for methionine sulfoxide and 0.19–201.20 μg/mL for pyroglutamic acid. The relatively simple method proved accurate (recovery 99.68–102.98% for methionine sulfoxide, 98.10–102.00% for pyroglutamic acid, n = 9) and precise (repeatability RSD = 1.06% for methionine sulfoxide, RSD = 0.60% for pyroglutamic acid, n = 6) in its application to commercial Compound Amino Acid Injection‐18 AA.
Targeting mitochondria with folic acid and vitamin B12ameliorates nicotine mediated islet cell dysfunction
Authors: Bhattacharjee Ankita , Prasad Shilpi Kumari , Banerjee Oly , Singh Siddhartha , Banerjee Arnab , Bose Ananya , Pal Swagata , Maji Bithin Kumar , Mukherjee Sandip 
Published: July 2018

AbstractNicotine, one of the well‐known highly toxic components of cigarette smoke, causes a number of adverse health effects and diseases. Our previous study has shown that nicotine induces reactive oxygen species (ROS) in islet cell and disrupts islet cell mitochondrial membrane potential (ΔΨm). However, supplementation with folic acid and vitamin B12were found effective against nicotine induced changes in pancreatic islet cells. But the toxicological effects and underlying mechanisms of nicotine‐induced mitochondrial dysfunction is still unknown. In this study, nicotine exposure decreases mitochondrial enzymes (pyruvate dehydrogenase, alpha‐ketoglutarate dehydrogenase, aconitase, malate dehydrogenase) activities by increasing cytosolic Ca2+level which may contribute to increased mitochondrial ROS production by raising its flow to mitochondria. This in turn produces malondialdehyde and nitric oxide (NO) with a concomitant decrease in the activities of antioxidative enzymes and glutathione levels leading to loss of ΔΨm. Simultaneously, nicotine induces pancreatic islet cell apoptosis by modulating ΔΨm via increased cytosolic Ca2+level, altered Bcl‐2, Bax, cytochrome c, caspase‐9, PARP expressions which were prevented by the supplementation of folic acid and vitamin B12. In conclusion, nicotine alters islet cell mitochondrial redox status, apoptotic machinery, and enzymes to cause disruption in the ΔΨm and supplementation of folic acid and vitamin B12possibly blunted all these mitochondrial alterations. Therefore, this study may help to determine the pathophysiology of nicotine‐mediated islet cell mitochondrial dysfunction.
Experiences of Women Who Have Had Carrier Testing for Duchenne Muscular Dystrophy and Becker Muscular Dystrophy During Adolescence
Authors: Fraser Harry G. , Redmond Rebecca Z. , Scotcher Diana F. 
Published: July 2018

AbstractDuchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are X‐linked recessive degenerative muscular conditions. Carrier testing is available to at‐risk females. Though carrier testing is often offered to adolescent females, it raises ethical issues related to autonomy. This study aimed to address the impact of DMD/BMD carrier testing during adolescence, to elucidate what motivates adolescents to seek testing, and to assess the carrier testing experience. Retrospective semi‐structured telephone interviews were conducted with 12 women out of 28 initially contacted. Data were coded using thematic analysis. For most (8/12) participants, discovering their carrier status during adolescence appeared to have helped alleviate uncertainty. The majority (9/12) of participants felt that they had made an autonomous decision and most (10/12) seemed to have adjusted well to their test result. Reproductive factors were framed as having been a key motivator prior to testing. However, following testing, participants’ views on prenatal diagnosis seemed more closely linked to their lived experience than to their test result. Just over half (7/12) the participants reported having not had the opportunity for genetic counseling prior to testing and after receiving their result, an issue that warrants further consideration.
The moderating effects of ethnicity on key predictors of trauma in child welfare involved adolescents
Authors: Washburn Micki , Carr L. Christian , Dettlaff Alan J. 
Published: July 2018

ABSTRACTKey predictors of trauma were examined using a multi‐group analysis of a nationally representative sample of 716 child welfare involved youth ages 11–17. Results indicate that co‐occurring clinical depression was associated with trauma across all racial/ethnic groups. Results also support that youth's ethnicity moderates the relationship between gender, history of sexual abuse and sexual orientation and the development of trauma. Contrary to prior research, trauma was not significantly associated with substance abuse or having experienced out of home placement for all ethnic groups. Implications for policy, practice with child welfare involved adolescents and future research in this area are discussed.