bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dimerization of Phenylalanine: An Approach to Thiazoles and Oxazoles Involved S/O‐Insertion
Authors: Cheng Yan , Xiang Jia‐Chen , Wang Zi‐Xuan , Ma Jin‐Tian , Wang Miao , Tang Bo‐Cheng , Wu Yan‐Dong , Zhu Yan‐Ping , Wu An‐Xin 
Published: November 2017

AbstractWe herein describe the development of a dimerization procedure for amino acids to prepare 2,5‐disubstituted thiazoles and oxazoles in the presence of Na2S⋅9H2O and H2O, respectively. These approaches enabled the direct formation of five‐membered ring systems bearing two different heteroatoms from two amino acid units. Mechanically, decarboxylation, deamination, S/O insertion, cyclization and gradient oxidation processes were involved in the oligomer formation.magnified image
Electrocatalysts for Hydrogen Evolution in Alkaline Electrolytes: Mechanisms, Challenges, and Prospective Solutions
Authors: Mahmood Nasir , Yao Yunduo , Zhang Jing‐Wen , Pan Lun , Zhang Xiangwen , Zou Ji‐Jun 
Published: November 2017

AbstractHydrogen evolution reaction (HER) in alkaline medium is currently a point of focus for sustainable development of hydrogen as an alternative clean fuel for various energy systems, but suffers from sluggish reaction kinetics due to additional water dissociation step. So, the state‐of‐the‐art catalysts performing well in acidic media lose considerable catalytic performance in alkaline media. This review summarizes the recent developments to overcome the kinetics issues of alkaline HER, synthesis of materials with modified morphologies, and electronic structures to tune the active sites and their applications as efficient catalysts for HER. It first explains the fundamentals and electrochemistry of HER and then outlines the requirements for an efficient and stable catalyst in alkaline medium. The challenges with alkaline HER and limitation with the electrocatalysts along with prospective solutions are then highlighted. It further describes the synthesis methods of advanced nanostructures based on carbon, noble, and inexpensive metals and their heterogeneous structures. These heterogeneous structures provide some ideal systems for analyzing the role of structure and synergy on alkaline HER catalysis. At the end, it provides the concluding remarks and future perspectives that can be helpful for tuning the catalysts active‐sites with improved electrochemical efficiencies in future.
Recent Progress in Single‐Crystalline Perovskite Research Including Crystal Preparation, Property Evaluation, and Applications
Authors: Liu Yucheng , Yang Zhou , Liu Shengzhong (Frank) 
Published: November 2017

AbstractOrganic–inorganic lead halide perovskites are promising optoelectronic materials resulting from their significant light absorption properties and unique long carrier dynamics, such as a long carrier lifetime, carrier diffusion length, and high carrier mobility. These advantageous properties have allowed for the utilization of lead halide perovskite materials in solar cells, LEDs, photodetectors, lasers, etc. To further explore their potential, intrinsic properties should be thoroughly investigated. Single crystals with few defects are the best candidates to disclose a variety of interesting and important properties of these materials, ultimately, showing the increased importance of single‐crystalline perovskite research. In this review, recent progress on the crystallization, investigation, and primary device applications of single‐crystalline perovskites are summarized and analyzed. Further improvements in device design and preparation are also discussed.
Safety and efficacy of early start of iron chelation therapy with deferiprone in young children newly diagnosed with transfusion‐dependent thalassemia: A randomized controlled trial
Authors: Elalfy Mohsen Saleh , Adly Amira , Awad Hanem , Tarif Salam Mohamed , Berdoukas Vasilios , Tricta Fernando 
Published: November 2017

AbstractIron overload is inevitable in patients who are transfusion dependent. In young children with transfusion‐dependent thalassemia (TDT), current practice is to delay the start of iron chelation therapy due to concerns over toxicities, which have been observed when deferoxamine was started too early. However, doing so may increase the risk of iron accumulation that will be manifested as toxicities later in life. This study investigated whether deferiprone, a chelator with a lower affinity for iron than deferoxamine, could postpone transfusional iron overload while maintaining a good safety profile. Recently diagnosed TDT infants (N = 64 their age ranged from 10 to 18 (median 12) months, 54.7% males; receiving ≤6 transfusions; serum ferittin (SF) >400 to < 1000 ng/mL were randomized to “early start deferiprone” (.ES‐DFP) at a low dose (50 mg/kg/day) or to “delay chelation” (DC), and remained in the study until their serum ferritin (SF) level reached ≥1000 μg/L. 61 patients continued the study Levels of transferrin saturation (TSAT) and labile plasma iron (LPI) were measured as well. By approximately 6 months postrandomization, 100% of the subjects in DC group had achieved SF > 1000 µg/L and TSAT > 70% compared with none in the ES‐DFP group. LPI level > 0.6 µM was observed in 97% vs. 40% of the DS and ES groups, respectively, (P < 0.001). The time to reach SF > 1000 µg/L was delayed by 6 months in the ES‐DFP group (P < 0.001) without escalating DFP dose. No unexpected, serious, or severe adverse events were seen in the ES‐DFP group.
A key role for Rac and Pak signaling in neutrophil extracellular traps (NETs) formation defines a new potential therapeutic target
Authors: Gavillet Mathilde , Martinod Kimberly , Renella Raffaele , Wagner Denisa D. , Williams David A. 
Published: November 2017

AbstractNET formation in mice (NETosis) is supported by reactive oxygen species (ROS) production by NADPH oxidase and histone hypercitrullination by peptidylarginine deiminase 4 (PAD4). Rac1 and Rac2, expressed in polymorphonuclear neutrophils (PMNs), regulate the cytoskeleton, cell shape, adhesion, and migration and are also essential components of the NADPH oxidase complex. We aimed to explore the role of the Rac signaling pathway including the upstream guanosine exchange factor (GEF) activator, Vav, and a downstream effector, the p21‐activated kinase, Pak, on NETosis in PMNs using a previously described flow‐cytometry‐based assay. Rac2‐/‐ PMNs showed reduced levels of citrullinated histone H3 (H3Cit)‐positive cells and defective NETosis. Rac1Δ/Δ; Rac2‐/‐ PMNs demonstrated a further reduction in PMA‐induced H3Cit levels and a more profound impairment of NETosis than deletion of Rac2 alone, suggesting an overlapping role of these two highly related proteins. Genetic knockouts of Vav1, or Vav2, did not impair H3Cit response to phorbol myristate ester (PMA) or NETosis. Combined, Vav1 and Vav3 deletions decreased H3Cit response and caused a modest but significant impairment of NETosis. Pharmacologic inhibition of Pak by two inhibitors with distinct mechanisms of action, led to reduced H3Cit levels after PMA stimulation, as well as significant inhibition of NETosis. We validated the importance of Pak using Pak2Δ/Δ PMNs, which demonstrated significantly impaired histone H3 citrullination and NETosis. These data confirm and more comprehensively define the key role of the Rac signaling pathway in PMN NETosis. The Rac signaling cascade may represent a valuable target for inhibition of NETosis and related pathological processes.
Self‐reported musculoskeletal disorder pain: The role of job hazards and work‐life interaction
Authors: Weale Victoria P. , Wells Yvonne , Oakman Jodi 
Published: November 2017

BackgroundPrevious research identified an association between work‐family conflict and musculoskeletal pain. This study explores how the work‐life interface might affect pain experienced by residential aged care staff.MethodsA cross‐sectional survey of 426 employees in residential aged care was analyzed to assess the impacts of workplace hazards, work‐family conflict, and work‐life balance on self‐reported musculoskeletal pain.ResultsWork‐family conflict acts as a mediator of the relationships between workplace hazards and the total number of body regions at which musculoskeletal pain was experienced. Work‐life balance only acts as a mediator for particular hazards and only if work‐family conflict is not taken into account.ConclusionsAddressing work‐life interaction, and in particular work‐family conflict, warrants further investigation as a legitimate means through which musculoskeletal disorder risk can be reduced. Policies and practices to improve work‐life interaction and reduce work‐family conflict should be considered as integral components of musculoskeletal disorder risk management strategies.
Integrated Transmission Electron and Single‐Molecule Fluorescence Microscopy Correlates Reactivity with Ultrastructure in a Single Catalyst Particle
Authors: Hendriks Frank C. , Mohammadian Sajjad , Ristanović Zoran , Kalirai Sam , Meirer Florian , Vogt Eelco T. C. , Bruijnincx Pieter C. A. , Gerritsen Hans C. , Weckhuysen Bert M. 
Published: November 2017

AbstractEstablishing structure–activity relationships in complex, hierarchically structured nanomaterials, such as fluid catalytic cracking (FCC) catalysts, requires characterization with complementary, correlated analysis techniques. An integrated setup has been developed to perform transmission electron microscopy (TEM) and single‐molecule fluorescence (SMF) microscopy on such nanostructured samples. Correlated structure–reactivity information was obtained for 100 nm thin, microtomed sections of a single FCC catalyst particle using this novel SMF‐TEM high‐resolution combination. High reactivity in a thiophene oligomerization probe reaction correlated well with TEM‐derived zeolite locations, while matrix components, such as clay and amorphous binder material, were found not to display activity. Differences in fluorescence intensity were also observed within and between distinct zeolite aggregate domains, indicating that not all zeolite domains are equally active.
Poröse Polyelektrolyte: Zusammenspiel zwischen Poren und Ladung für neue Funktionen
Authors: Zhang Weiyi , Zhao Qiang , Yuan Jiayin 
Published: November 2017

AbstractDas Gebiet poröser Polyelektrolyte hat im letzten Jahrzehnt eine rasante Entwicklung genommen. Das Interesse richtet sich zurzeit auf die Synthese dieser Materialien und ihre Anwendung in der Umwelt‐, Energie‐, Biomedizin‐ und Katalysetechnik. Für poröse Polyelektrolyte stehen verschiedene funktionelle organische Gruppen und Verarbeitungstechniken zur Auswahl, attraktiv macht diese Materialien jedoch vor allem das Zusammenspiel zwischen Ladung und Porenabmessungen in verschiedenen Längenbereichen, von einzelnen Polyelektrolytgerüsten bis hin zu ihren Nano‐/Mikroüberstrukturen. Dieser Aufsatz beschäftigt sich mit neuen Entwicklungen bei porösen Polyelektrolyten und schließt Membranen, Partikel, Gerüste, Pulver sowie Harze mit großer spezifischer Oberfläche sowie deren Derivate ein. Er konzentriert sich dabei auf das Zusammenspiel zwischen Oberflächenchemie, Coulomb‐Wechselwirkungen und Porenbeschränkung, was für die Chemie und Physik dieser Materialien bei Anwendungen auf den Gebieten der Energieumwandlung, Molekültrennung, Wasseraufbereitung, Sensortechnik/Aktuation, Katalyse, Gewebezüchtung und Nanomedizin relevant ist.
GOx@ZIF‐8(NiPd) Nanoflower: An Artificial Enzyme System for Tandem Catalysis
Authors: Wang Qingqing , Zhang Xueping , Huang Liang , Zhang Zhiquan , Dong Shaojun 
Published: November 2017

AbstractWe report a facile approach to prepare an artificial enzyme system for tandem catalysis. NiPd hollow nanoparticles and glucose oxidase (GOx) were simultaneously immobilized on the zeolitic imidazolate framework 8 (ZIF‐8) via a co‐precipitation method. The as‐prepared GOx@ZIF‐8(NiPd) nanoflower not only exhibited the peroxidase‐like activity of NiPd hollow nanoparticles but also maintained the enzymatic activity of GOx. A colorimetric sensor for rapid detection of glucose was realized through the GOx@ZIF‐8(NiPd) based multi‐enzyme system. Moreover, the GOx@ZIF‐8(NiPd) modified electrode showed good bioactivity of GOx and high electrocatalytic activity for the oxygen reduction reaction (ORR), which could also be used for electrochemical detection of glucose.
Porous Polyelectrolytes: The Interplay of Charge and Pores for New Functionalities
Authors: Zhang Weiyi , Zhao Qiang , Yuan Jiayin 
Published: November 2017

AbstractThe past decade has witnessed rapid advances in porous polyelectrolytes and there is tremendous interest in their synthesis as well as their applications in environmental, energy, biomedicine, and catalysis technologies. Research on porous polyelectrolytes is motivated by the flexible choice of functional organic groups and processing technologies as well as the synergy of the charge and pores spanning length scales from individual polyelectrolyte backbones to their nano‐/micro‐superstructures. This Review surveys recent progress in porous polyelectrolytes including membranes, particles, scaffolds, and high surface area powders/resins as well as their derivatives. The focus is the interplay between surface chemistry, Columbic interaction, and pore confinement that defines new chemistry and physics in such materials for applications in energy conversion, molecular separation, water purification, sensing/actuation, catalysis, tissue engineering, and nanomedicine.
Single and binary catalyst systems based on nickel and palladium in polymerization of ethylene
Authors: Kimiaghalam Mahsa , Isfahani Hossein Nasr , Zohuri Gholam Hossein , Keivanloo Ali 
Published: November 2017

The catalyst (N,N‐bis(2,6‐dibenzhydryl‐4‐ethoxyphenyl)butane‐2,3‐diimine)nickel dibromide, a late transition metal catalyst, was prepared and used in ethylene polymerization. The effects of reaction parameters such as polymerization temperature, co‐catalyst to catalyst molar ratio and monomer pressure on the polymerization were investigated. The α‐diimine nickel‐based catalyst was demonstrated to be thermally robust at a temperature as high as 90 °C. The highest activity of the catalyst (494 kg polyethylene (mol cat)−1 h−1) was obtained at [Al]/[Ni] = 600:1, temperature of 90 °C and pressure of 5 bar. In addition, the performance of a binary catalyst using nickel‐ and palladium‐based complexes was compared with that of the corresponding individual catalytic systems in ethylene polymerization. In a study of the catalyst systems, the average molecular weight and molecular weight distribution for the binary polymerization were between those for the individual catalytic polymerizations; however, the binary catalyst activity was lower than that of the two individual ones. The obtained polyethylenes had high molecular weights in the region of 105 g mol−1. Gel permeation chromatography analysis showed a narrow molecular weight distribution of 1.44 for the nickel‐based catalyst and 1.61 for the binary catalyst system. The branching density of the polyethylenes generated using the binary catalytic system (30 branches/1000 C) was lower than that generated using the nickel‐based catalyst (51/1000 C). X‐ray diffraction study of the polymer chains showed higher crystallinity with lower branching of the polymer obtained. Also Fourier transform infrared spectra confirmed that all obtained polymers were low‐density polyethylene.
Preparation and characterization of higher degree‐deacetylated chitosan‐coated magnetic adsorbent for the removal of chromium(VI) from its aqueous mixture
Authors: Ravi T. , Anuradha Jabasingh S. 
Published: November 2017

ABSTRACTChitosan (90% deacetylated) coated magnetic adsorbent prepared by coprecipitation method to remove Cr(VI) from its aqueous solution. The experimental studies depicts that the predominant option for removal of Chromium by adsorption from its aqueous phase using Magnetic‐Chitosan (MC). The subsequent physical, chemical, and magnetic properties of MC were characterized by X‐ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectrometer, vibrating sample magnetometer. The influence of batch process parameters such as contact time, initial concentration, pH, and coexisting anions were investigated. The Box‐Behnken experimental design in response surface methodology was performed to design the experiment optimal operating conditions. The maximum percentage reduction of Cr(VI) is 96.3 that was obtained by magnetic chitosan with the optimal operating conditions of 149.53 mg/L at pH of 5.32 at the contact time of 80 min and at the temperature of 303 K. The average diameter of the magnetic chitosan was calculated from X‐ray diffractometer analysis as 24.5 nm. The equilibrium adsorption isotherm models such as Langmuir and Freundlich and the adsorption kinetics such as pseudo first order, pseudo second order and intra‐particle diffusion kinetic model were analyzed. The experimental data's suited for the best fit with the Langmuir isotherm model and pseudo first order kinetic model. It also revealed that Cr(VI) adsorption on MC is intrinsically exothermic and spontaneous. The magnetic chitosan was also used to investigate for the removal of Cr(VI) from the real water sources such as surface, underground, and tannery wastewater. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45878.
Remendable polymers via reversible Diels–Alder cycloaddition of anthracene‐containing copolymers with fullerenes
Authors: Kötteritzsch Julia , Geitner Robert , Ahner Johannes , Abend Marcus , Zechel Stefan , Vitz Jürgen , Hoeppener Stephanie , Dietzek Benjamin , Schmitt Michael , Popp Jürgen , Schubert Ulrich S. , Hager Martin D. 
Published: November 2017

ABSTRACTPoly(lauryl methacrylate)s with anthracene moieties in the side chain were converted with C60‐fullerene and phenyl‐C61‐butyric acid methyl ester (PCBM), resulting in new remendable (self‐healing) polymeric materials. The utilization of differently substituted anthracene monomers enabled the tuning of the reactivity and the resulting mechanical properties. Copolymers with different contents of the anthracene moieties were synthesized and characterized using size exclusion chromatography, 1H nuclear magnetic resonance (NMR) spectroscopy as well as differential scanning calorimetry (DSC). 1H NMR spectroscopic studies were utilized in order to investigate the reversibility of the Diels–Alder reaction between copolymers with C60‐fullerene and PCBM, respectively, in solution. In order to investigate the conversion of the polymers with C60‐fullerene and PCBM in bulk, additionally, DSC, nanoindentation, rheology, atomic force microscopy (AFM), 3D microscopy, simultaneous thermal analysis (STA) and FT‐Raman investigations were performed. The fullerene‐containing copolymers could be healed in a temperature range of 40–80 °C. Consequently, a new generation of low temperature remendable polymers could be established. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45916.
Individual differences in EEG correlates of recognition memory due to DAT polymorphisms
Authors: Medrano Paolo , Nyhus Erika , Smolen Andrew , Curran Tim , Ross Robert S. 
Published: November 2017

AbstractIntroductionAlthough previous research suggests that genetic variation in dopaminergic genes may affect recognition memory, the role dopamine transporter expression may have on the behavioral and EEG correlates of recognition memory has not been well established.ObjectivesThe study aims to reveal how individual differences in dopaminergic functioning due to genetic variations in the dopamine transporter gene influences behavioral and EEG correlates of recognition memory.MethodsFifty‐eight participants performed an item recognition task. Participants were asked to retrieve 200 previously presented words while brain activity was recorded with EEG. Regions of interest were established in scalp locations associated with recognition memory. Mean ERP amplitudes and event‐related spectral perturbations when correctly remembering old items (hits) and recognizing new items (correct rejections) were compared as a function of dopamine transporter group.ResultsParticipants in the dopamine transporter group that codes for increased dopamine transporter expression (10/10 homozygotes) display slower reaction times compared to participants in the dopamine transporter group associated with the expression of fewer dopamine transporters (9R‐carriers). 10/10 homozygotes further displayed differences in ERP and oscillatory activity compared to 9R‐carriers. 10/10 homozygotes fail to display the left parietal old/new effect, an ERP signature of recognition memory associated with the amount of information retrieved. 10/10 homozygotes also displayed greater decreases of alpha and beta oscillatory activity during item memory retrieval compared to 9R‐carriers.ConclusionCompared to 9R‐carriers, 10/10 homozygotes display slower hit and correct rejection reaction times, an absence of the left parietal old/new effect, and greater decreases in alpha and beta oscillatory activity during recognition memory. These results suggest that dopamine transporter polymorphisms influence recognition memory.
Toenail mineral concentration and risk of esophageal squamous cell carcinoma, results from the Golestan Cohort Study
Authors: Hashemian Maryam , Murphy Gwen , Etemadi Arash , Poustchi Hossein , Brockman John D. , Kamangar Farin , Pourshams Akram , Khoshnia Masoud , Gharavi Abdolsamad , Dawsey Sanford M. , Brennan Paul. J. , Boffetta Paolo. , Hekmatdoost Azita , Malekzadeh Reza , Abnet Christian C. 
Published: November 2017

AbstractStudies conducted in China linked selenium deficiency to higher risk of esophageal squamous cell carcinoma (ESCC), but this has not been widely tested outside that selenium‐deficient region. The aim of this study was to investigate the association between selenium and other mineral concentrations in toenails and risk of ESCC in a region with high incidence rates. In this nested case–control study, we identified 222 cases of ESCC from the Golestan Cohort Study, Iran, which has followed up 50,045 participants since enrollment (2004–2008). We randomly selected one control for each case matched by age and sex, using incidence density sampling. We used toenail samples collected at baseline to measure the concentration of selenium, zinc, chromium, mercury, and scandium using instrumental neutron activation analysis. Multivariate adjusted logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals. Median nail selenium, zinc, chromium, and mercury levels were 1.01, 74.59, 0.77, and 0.018 μg/g in cases and 1.02, 75.71, 0.71, and 0.023 μg/g in controls, respectively. The adjusted odds ratios comparing each fourth quartile of mineral status versus the first quartile were as follows: selenium = 0.78 (95% CI, 0.41–1.49); zinc=0.80 (95% CI, 0.42–1.53); chromium = 0.91 (95% CI, 0.46–1.80); and mercury=0.61 (95% CI, 0.27–1.38), and all trend tests were non–significant. The nail selenium concentration in our controls reflects relatively high selenium status. No evidence of association between selenium or chromium concentrations in toenails and the risk of ESCC was detected in this population.