bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anchoring Nitrogen‐Doped TiO2 Nanocrystals on Nitrogen‐Doped 3D Graphene Frameworks for Enhanced Lithium Storage
Authors: Liu Xiao‐Wu , Yang Zhen‐Zhong , Pan Fu‐Sen , Gu Lin , Yu Yan 
Published: December 2016

AbstractAn advanced architecture design of nitrogen‐doped TiO2 anchored on nitrogen‐doped 3D graphene framework composites (denoted as N‐TiO2/N‐3D GFs) have been fabricated by a facile template process and further NH3 treatment. The 3D graphene framework allows the electrolyte to penetrate into the inverse opal structure, and possesses high electronic conductivity. The close contact between the N‐TiO2 and the graphene suppresses the growth and aggregation of TiO2 nanoparticles during heating process, leading to decreased Li+ diffusion length. The N‐doping in both TiO2 and the graphene matrix could improve the electronic conductivity on the TiO2 particle surface and between adjacent particles. As expected, when used as an anode for Li‐ion batteries (LIBs), the N‐TiO2/N‐3D GFs composite delivers an excellent reversible capacity of 165 mA h g−1 after 200 cycles at 100 mA g−1 and an outstanding rate capability of 114 mA h g−1 after 1000 cycles at 1 Ag−1. With rational design, this strategy could be extended to other electrode materials that may hold great promise for the development of high energy storage systems.
Reduction of [Cp*Sb]4with Subvalent Main‐Group Metal Reductants: Syntheses and Structures of [(L1Mg)4(Sb4)] and [(L2Ga)2(Sb4)] Containing Edge‐Missing Sb4Units
Authors: Ganesamoorthy Chelladurai , Krüger Julia , Wölper Christoph , Nizovtsev Anton S. , Schulz Stephan 
Published: December 2016

Abstract[Cp*Sb]4(Cp*=C5Me5) reacts with [L1Mg]2and L2Ga with formation of [(L1Mg)4(μ4,η1:2:2:2‐Sb4)] (L1=iPr2NC[N(2,6‐iPr2C6H3)]2,1) and [(L2Ga)2(μ,η2:2‐Sb4)] (L2=HC[C(Me)N(2,6‐iPr2C6H3)]2,2). The cleavage of the Sb−Sb and Sb−C bonds in [Cp*Sb]4are the crucial steps in both reactions. The formation of1occurred by elimination of the Cp* anion and formation of Cp*MgL1, while2was formed by reductive elimination of Cp*2and oxidative addition of L2Ga to the Sb4unit.1and2were characterized by heteronuclear NMR spectroscopy and single‐crystal X‐ray diffraction, and their bonding situation was studied by quantum chemical calculations.
Bichromophoric Compounds with Orthogonally and Parallelly Arranged Chromophores Separated by Rigid Spacers
Authors: Meineke Dirk N. H. , Bossi Mariano L. , Ta Haisen , Belov Vladimir N. , Hell Stefan W. 
Published: December 2016

AbstractElectronic energy transfer (EET) between chromophores is of fundamental importance for many biological processes and optoelectronic devices. However, common models fall short in fully describing the process, especially in bichromophoric model systems with a donor and acceptor connected by a rigid linker providing perpendicular geometries. Herein, we report a novel strategy for preparing bichromophores containing adamantane or 2‐(2‐adamantylidene)adamantane as rigid spacers, providing a fixed distance between chromophores, and their parallel or perpendicular arrangement without chromophore rotation. New fluorophores were developed and linked via spiroatoms. Bichromophores with identical (blue‐blue) or different (blue‐red) chromophores were synthesized, either in orthogonal or parallel geometry. These were characterized by absorption/fluorescence spectroscopy, time‐resolved fluorescence anisotropy, and fluorescence antibunching measurements. Based on the Förster point‐dipole approximation, EET efficiencies were estimated by using geometrical parameters from (time‐dependent) density functional calculations. For bichromophores with parallel geometry, the predicted EET efficiencies were near unity and fit the measurements. In spite of estimated values around 0.4 and 0.5, 100 % efficiency was observed also for bichromophores with orthogonal geometry. The new rigid scaffolds presented here open new possibilities for the synthesis of bichormophores with well‐defined parallel or perpendicular geometry.
Trimetallic Au‐Cu‐K/AC for acetylene hydrochlorination
Authors: Wang Lei , Shen Benxian , Zhao Jigang , Bi Xiaotao 
Published: December 2016

AbstractThe metal chloride of KCl was chosen to modify Au‐Cu/AC to decrease the noble metal of gold and enhance the catalytic performance. Then a mercury‐free catalyst of Au‐Cu‐K/AC was prepared by the impregnation method. The catalytic performances of mercury‐free catalyst for acetylene hydrochlorination were conducted for 1600 h in a fixed bed reactor by a single‐tube pilot unit. The fresh and used catalysts were also characterized in comparison. The results showed that the acetylene conversion on mercury‐free catalyst decreased slowly from 98 % to 89 %, and the vinyl chloride monomer (VCM) selectivity was kept at 99.7 % under reaction conditions of temperature 165 °C, gas hourly space velocity (GHSV) 40 h−1, and feed volume ratio of HCl to C2H2 of 1.05 during 1600 h on stream. The results showed that the additives of K with Cu can make the active species of gold dispersed well and retard the aggregation of particles. The reason for the slow decline of acetylene conversion for Au‐Cu‐K/AC catalyst was the whisker carbon deposition, shown in a faint yellow colour over the catalyst surface, which consisted of short‐chain hydrocarbon molecules. Further study for accelerated deactivation of sole metal in the catalyst gives the clues that the non‐noble metal of Cu in Au‐Cu‐K/AC catalyst plays a key role to form the deposition.
Potential effect of chemical and thermal treatment on the Kinetics, equilibrium, and thermodynamic studies for atrazine biosorption by the Moringa oleifera pods
Authors: Coldebella Priscila Ferri , Fagundes‐Klen Márcia Regina , Nishi Letícia , Valverde Karina Cardoso , Cavalcanti Eliane Bezerra , Andreo dos Santos Onélia Aparecida , Bergamasco Rosângela 
Published: December 2016

AbstractThe effectiveness of chemical and thermal pretreatments on Moringa oleifera pods for the atrazine removal from water was investigated. The untreated pods (MOPun), the chemically treated pods (MOPC), and the chemically treated pods followed by the thermally treated pods (MOPT) were physico‐chemically and morphologically characterized by elemental, pHZPC, N2 physisorption, FTIR, and SEM analysis. The effect of modified pods was significant in increasing surface porosity, favouring the surface chemistry, and improving the atrazine biosorption capacity. Kinetics data were best explained by pseudo‐second order model for all biosorbents. The equilibrium data for biosorption were analyzed by using Langmuir, Freundlich, Sips, and Polanyi‐Manes (PMM) isotherm models to define the best correlation for atrazine biosorption capacity. Among the four isotherm models, both Sips and PMM were the models best fitted with the equilibrium isotherm for atrazine. The maximum atrazine adsorption capacities were 0.629, 1.580, and 7.47 mg · g−1 for MOPun, MOPC, and MOPT respectively with a maximum removal percentage of 65 %, 82 %, and 99 %. The thermodynamic studies showed that atrazine biosorption is favourable. The biosorption experiments demonstrated that Moringa oleifera pods have great potential for removing atrazine and other organic contaminants from water.
Polyvinylpyrrolidone (PVP)‐Capped Pt Nanocubes with Superior Peroxidase‐Like Activity
Authors: Ye Haihang , Liu Yuzi , Chhabra Ashima , Lilla Emily , Xia Xiaohu 
Published: December 2016

AbstractPeroxidase mimics composed of inorganic nanoparticles are expected to circumvent the inherent difficulties of natural peroxidases, and to provide enhanced performance in important applications such as diagnosis and imaging. Despite the reports of a variety of peroxidase mimics in the past decade, very limited progress has been made on improving their catalytic efficiency. The catalytic efficiencies of most previously reported mimics are only up to one order of magnitude higher than those of natural peroxidases. In this work, we demonstrate a highly efficient peroxidase—polyvinylpyrrolidone (PVP)‐capped Pt nanocubes of sub‐10 nm in size. These PVP‐capped Pt cubes are ≈200‐fold more active than the natural counterparts and exhibit a record‐high specific catalytic efficiency. In addition to the superior efficiency, the new mimic shows several other promising features, including excellent stabilities, well‐controlled uniformity in both size and shape, controllable sizes, and facile and scalable production.
Laser Alloying of Co Nanorods and Al Nanoparticles in a Liquid
Authors: Barmina Ekaterina V. , Sukhov Ilya A. , Viau Guillaume , Shafeev Georgy A. 
Published: December 2016

AbstractExperimental results are presented on laser alloying of Co nanorods with Al spherical nanoparticles by laser exposure of their mixture in liquid ethanol. It is demonstrated that the initial morphology of the nanoparticles is modified upon laser exposure. The Co nanorods are transformed into Co nanospheres covered by a layer of Al. The evolution of the size distribution is studied as a function of the time of laser exposure. The average size of the nanoparticles has a maximum level with a corresponding optimal irradiation time. The results are discussed from the viewpoint of the interaction of molten nanoparticles inside a cavitation bubble filled with a liquid vapor.
“Practical” Electrospinning of Biopolymers in Ionic Liquids
Authors: Shamshina Julia L. , Zavgorodnya Oleksandra , Bonner Jonathan R. , Gurau Gabriela , Di Nardo Thomas , Rogers Robin D. 
Published: December 2016

AbstractTo address the need to scale up technologies for electrospinning of biopolymers from ionic liquids to practical volumes, a setup for the multi‐needle electrospinning of chitin using the ionic liquid 1‐ethyl‐3‐methylimidazolium acetate, [C2mim]‐[OAc], was designed, built, and demonstrated. Materials with controllable and high surface area were prepared at the nanoscale using ionic‐liquid solutions of high‐molecular‐weight chitin extracted with the same ionic liquid directly from shrimp shells.
One‐Pot Preparation of Dimethyl Isosorbide from d‐Sorbitol via Dimethyl Carbonate Chemistry
Authors: Aricò F. , Aldoshin A. S. , Tundo P. 
Published: December 2016

AbstractDirect synthesis of dimethyl isosorbide (DMI) from d‐sorbitol via dimethyl carbonate (DMC) chemistry is herein first reported. High yield of DMI was achieved using the nitrogen superbase 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD) as catalyst and performing the reaction in a stainless steel autoclave by increasing the temperature from 90 to 200 °C. In this procedure, DMC features its full capacity acting in the different steps of the process as carboxymethylating, leaving‐group (cyclization), and methylating agent; DMC is also employed as the reaction media.
A Robust Molecular Catalyst Generated In Situ for Photo‐ and Electrochemical Water Oxidation
Authors: Younus Hussein A. , Ahmad Nazir , Chughtai Adeel H. , Vandichel Matthias , Busch Michael , Van Hecke Kristof , Yusubov Mekhman , Song Shaoxian , Verpoort Francis 
Published: December 2016

AbstractWater splitting is the key step towards artificial photosystems for solar energy conversion and storage in the form of chemical bonding. The oxidation of water is the bottle‐neck of this process that hampers its practical utility; hence, efficient, robust, and easy to make catalytic systems based on cheap and earth‐abundant materials are of exceptional importance. Herein, an in situ generated cobalt catalyst, [CoII(TCA)2(H2O)2] (TCA=1‐mesityl‐1,2,3‐1H‐triazole‐4‐carboxylate), that efficiently conducts photochemical water oxidation under near‐neutral conditions is presented. The catalyst showed high stability under photolytic conditions for more than 3 h of photoirradiation. During electrochemical water oxidation, the catalytic system assembled a catalyst film, which proved not to be cobalt oxide/hydroxide as normally expected, but instead, and for the first time, generated a molecular cobalt complex that incorporated the organic ligand bound to cobalt ions. The catalyst film exhibited a low overpotential for electrocatalytic water oxidation (360 mV) and high oxygen evolution peak current densities of 9 and 2.7 mA cm−2 on glassy carbon and indium‐doped tin oxide electrodes, respectively, at only 1.49 and 1.39 V (versus a normal hydrogen electrode), respectively, under neutral conditions. This finding, exemplified on the in situ generated cobalt complex, might be applicable to other molecular systems and suggests that the formation of a catalytic film in electrochemical water oxidation experiments is not always an indication of catalyst decomposition and the formation of nanoparticles.
Effective Release of Lignin Fragments from Lignocellulose by Lewis Acid Metal Triflates in the Lignin‐First Approach
Authors: Huang Xiaoming , Zhu Jiadong , Korányi Tamás I. , Boot Michael D. , Hensen Emiel J. M. 
Published: December 2016

AbstractInvited for this month′s cover is the group of Emiel Hensen at the Eindhoven University of Technology. The image shows how the lignin component can be effectively released from wood and converted into aromatics over a tandem Al‐triflate and Pd/C catalyst. The Communication itself is available at 10.1002/cssc.201601252.
Subacute right heart failure revealing three simultaneous causes of post‐embolic pulmonary hypertension in metastatic dissemination of breast cancer
Authors: Vincent Flavien , Lamblin Nicolas , Classe Marion , Schurtz Guillaume , Rauch Antoine , Fertin Marie , De Groote Pascal 
Published: December 2016

AbstractA 72‐year‐old woman with history of breast cancer only treated surgically was referred to our department for pulmonary hypertension (PH) suspicion. Echocardiogram revealed elevated right ventricular systolic pressure. Computed tomography (CT) angiogram showed no pulmonary embolism (PE), but lung scan revealed two ventilation‐perfusion mismatch areas. Right cardiac catheterization established precapillary PH. Despite treatment with PH specific therapy (sildenafil, ambrisentan, and epoprostenol), her condition worsened rapidly with acute right heart failure (RHF). She died 22 days after admission. Post‐mortem microscopic examination showed a rare combination of PH etiologies consistent with metastasis of breast cancer in pulmonary vasculature including the rare pulmonary tumour thrombotic microangiopathy (PTTM).
Cyclic behavior and failure mechanism of self‐centering energy dissipation braces with pre‐pressed combination disc springs
Authors: Xu Long‐He , Fan Xiao‐Wei , Li Zhong‐Xian 
Published: December 2016

SummaryA new type of bracing system composed of friction energy dissipation devices for energy dissipation, pre‐pressed combination disc springs for self‐centering and tube members as guiding elements is developed and experimentally studied in this paper. The mechanics of this system are explained, the equations governing its hysteretic responses are outlined and large‐scale validation tests of two braces with different types of disc springs are conducted under the condition of low cyclic reversed loading. The experimental results demonstrate that the proposed bracing system exhibits a stable and repeatable flag‐shaped hysteretic response with an excellent self‐centering capability and effective energy dissipation throughout the loading protocol. Furthermore, the maximum bearing force and stiffness are predicted well by the equations governing its mechanical behavior. Fatigue and destructive test results demonstrate that the proposed bracing system can maintain stable energy dissipation and self‐centering capabilities under large deformation cyclic loading even when the tube members exceed the elastic limit and that a larger bearing capacity is achieved by the system that has disc springs without a bearing surface. Copyright © 2016 John Wiley & Sons, Ltd.
Characterization of the Pro‐Inflammatory Cytokine IL‐1β on Butyrate Oxidation in Colorectal Cancer Cells
Authors: Johnstone Megan , Bennett Natalie , Standifer Cynthia , Smith Alexis , Han Anna , Bettaieb Ahmed , Whelan Jay , Donohoe Dallas R. 
Published: December 2016

ABSTRACTCancer, in part, is driven, by alterations in cellular metabolism that promote cell survival and cell proliferation. Identifying factors that influence this shift in cellular metabolism in cancer cells is important. Interleukin‐1β (IL‐1β) is a pro‐inflammatory cytokine that has been reported to be elevated in colorectal cancer patients. While much is known toward the effect of dietary nutrients on regulating inflammation and the inflammatory response, which includes cytokines such as IL‐1β, far less is understood how cytokines impact nutrient fate to alter cancer cell metabolism. Butyrate, a nutrient derived from the fermentation of dietary fiber in the colon, is the preferential exogenous energetic substrate used by non‐cancerous colonocytes, but is used less efficiently by colorectal cancer cells. To test whether IL‐1β alters colonocyte energy metabolism, we measured butyrate oxidation in HCT116 colorectal cancer cells with and without IL‐1β. We hypothesize that IL‐1β will push cancerous colonocytes away from the utilization and oxidation of butyrate. In this study, we demonstrate that pretreatment of colorectal cancer cells with IL‐1β diminished butyrate oxidation and NADH levels. This effect was blocked with the interleukin receptor antagonist A (IL‐1RA). Moreover, IL‐1β suppressed basal mitochondrial respiration and lowered the mitochondrial spare capacity. By using inhibitors to block downstream targets of the interleukin‐1 receptor pathway, we show that p38 is required for the IL‐1β‐mediated decrease in butyrate oxidation. These data provide insight into the metabolic effects induced by IL‐1β in colorectal cancer, and identify relevant targets that may be exploited to block the effects of this cytokine. J. Cell. Biochem. 118: 1614–1621, 2017. © 2016 Wiley Periodicals, Inc.
Evidence for Pipecolate Oxidase in Mediating Protection Against Hydrogen Peroxide Stress
Authors: Natarajan Sathish Kumar , Muthukrishnan Ezhumalai , Khalimonchuk Oleh , Mott Justin L. , Becker Donald F. 
Published: December 2016

ABSTRACTPipecolate, an intermediate of the lysine catabolic pathway, is oxidized to Δ1‐piperideine‐6‐carboxylate (P6C) by the flavoenzyme l‐pipecolate oxidase (PIPOX). P6C spontaneously hydrolyzes to generate α‐aminoadipate semialdehyde, which is then converted into α‐aminoadipate acid by α‐aminoadipatesemialdehyde dehydrogenase. l‐pipecolate was previously reported to protect mammalian cells against oxidative stress. Here, we examined whether PIPOX is involved in the mechanism of pipecolate stress protection. Knockdown of PIPOX by small interference RNA abolished pipecolate protection against hydrogen peroxide‐induced cell death in HEK293 cells suggesting a critical role for PIPOX. Subcellular fractionation analysis showed that PIPOX is localized in the mitochondria of HEK293 cells consistent with its role in lysine catabolism. Signaling pathways potentially involved in pipecolate protection were explored by treating cells with small molecule inhibitors. Inhibition of both mTORC1 and mTORC2 kinase complexes or inhibition of Akt kinase alone blocked pipecolate protection suggesting the involvement of these signaling pathways. Phosphorylation of the Akt downstream target, forkhead transcription factor O3 (FoxO3), was also significantly increased in cells treated with pipecolate, further implicating Akt in the protective mechanism and revealing FoxO3 inhibition as a potentially key step. The results presented here demonstrate that pipecolate metabolism can influence cell signaling during oxidative stress to promote cell survival and suggest that the mechanism of pipecolate protection parallels that of proline, which is also metabolized in the mitochondria. J. Cell. Biochem. 118: 1678–1688, 2017. © 2016 Wiley Periodicals, Inc.
Tomentosin Induces Telomere Shortening and Caspase‐Dependant Apoptosis in Cervical Cancer Cells
Authors: Merghoub Nawel , El Btaouri Hassan , Benbacer Laila , Gmouh Saïd , Trentesaux Chantal , Brassart Bertrand , Attaleb Mohammed , Madoulet Claudie , Wenner Thomas , Amzazi Saaid , Morjani Hamid , El Mzibri Mohamed 
Published: December 2016

ABSTRACTTomentosin, a natural sesquiterpene lactone purified from of Inula viscosa L., was investigated for its anti‐proliferative, telomere shortening, and apoptotic effects on human cervical cancer HeLa and SiHa cell lines. Tomentosin was found to inhibit the growth of SiHa and HeLa cell lines in dose and time‐dependent manner (IC50 values of 7.10 ± 0.78 μM and 5.87 ± 0.36 μM, respectively after 96 h of treatment). As evidenced by TTAGGG telomere length assay, tomentosin target specifically the telomeric overhang lengthening. This was confirmed by the evaluation of the cytotoxic effects of tomentosin in the foetal fibroblast Wi38 and JW10 cells which were derived from Wi38 and express hTERT, the telomerase catalytic subunit. We found that JW10 cells are 4.7‐fold more sensitive to tomentosin which argues for telomere as its specific target. Furthermore, we found that tomentosin mediate this cytotoxic effect by inducing apoptosis and cell cycle arrest at G2/M phase. Morphological features of treated cells, as evidenced by Hoechst 33324 staining, revealed that the cytotoxic effect was due to induction of apoptosis. This was accompanied by pro‐caspase‐3 cleavage, an increase in caspase‐3 activity and a cleavage of poly (ADP‐ribose) polymerase (PARP). Moreover, tomentosin induced a decrease in mitochondrial membrane potential (ΔΨm) and an increase in reactive oxygen species (ROS), accompanied by a decrease in Bcl‐2 expression. This indicates that tomentosin‐induced apoptosis may involve a mitochondria‐mediated signaling pathway. This study provides the first evidence that tomentosin targets telomere machinery and induces apoptosis in cervical cancer cells. The molecular mechanism underlying tomentosin‐induced apoptosis may involve a mitochondria‐mediated signaling pathway. J. Cell. Biochem. 118: 1689–1698, 2017. © 2016 Wiley Periodicals, Inc.
Markov Mixed Effects Modeling Using Electronic Adherence Monitoring Records Identifies Influential Covariates to HIV Preexposure Prophylaxis
Authors: Madrasi Kumpal , Chaturvedula Ayyappa , Haberer Jessica E. , Sale Mark , Fossler Michael J. , Bangsberg David , Baeten Jared M. , Celum Connie , Hendrix Craig W. 
Published: December 2016

AbstractAdherence is a major factor in the effectiveness of preexposure prophylaxis (PrEP) for HIV prevention. Modeling patterns of adherence helps to identify influential covariates of different types of adherence as well as to enable clinical trial simulation so that appropriate interventions can be developed. We developed a Markov mixed‐effects model to understand the covariates influencing adherence patterns to daily oral PrEP. Electronic adherence records (date and time of medication bottle cap opening) from the Partners PrEP ancillary adherence study with a total of 1147 subjects were used. This study included once‐daily dosing regimens of placebo, oral tenofovir disoproxil fumarate (TDF), and TDF in combination with emtricitabine (FTC), administered to HIV‐uninfected members of serodiscordant couples. One‐coin and first‐ to third‐order Markov models were fit to the data using NONMEM® 7.2. Model selection criteria included objective function value (OFV), Akaike information criterion (AIC), visual predictive checks, and posterior predictive checks. Covariates were included based on forward addition (α = 0.05) and backward elimination (α = 0.001). Markov models better described the data than 1‐coin models. A third‐order Markov model gave the lowest OFV and AIC, but the simpler first‐order model was used for covariate model building because no additional benefit on prediction of target measures was observed for higher‐order models. Female sex and older age had a positive impact on adherence, whereas Sundays, sexual abstinence, and sex with a partner other than the study partner had a negative impact on adherence. Our findings suggest adherence interventions should consider the role of these factors.