bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and Stability of Carbohydrate–Lipid Interactions. Methylmannose Polysaccharide–Fatty Acid Complexes
Authors: Liu Lan , Siuda Iwona , Richards Michele R. , Renaud Justin , Kitova Elena N. , Mayer Paul M. , Tieleman D. Peter , Lowary Todd L. , Klassen John S.
Published: June 2016

We report a detailed study of the structure and stability of carbohydrate–lipid interactions. Complexes of a methylmannose polysaccharide (MMP) derivative and fatty acids (FAs) served as model systems. The dependence of solution affinities and gas‐phase dissociation activation energies (Ea) on FA length indicates a dominant role of carbohydrate–lipid interactions in stabilizing (MMP+FA) complexes. Solution 1H NMR results reveal weak interactions between MMP methyl groups and FA acyl chain; MD simulations suggest the complexes are disordered. The contribution of FA methylene groups to the Ea is similar to that of heats of transfer of n‐alkanes from the gas phase to polar solvents, thus suggesting that MMP binds lipids through dipole‐induced dipole interactions. The MD results point to hydrophobic interactions and H‐bonds with the FA carboxyl group. Comparison of collision cross sections of deprotonated (MMP+FA) ions with MD structures suggests that the gaseous complexes are disordered.
Enhanced Reactivity of Water Clusters towards Oxidation in Water/Acetonitrile Mixtures
Authors: Hidalgo‐Acosta Jonnathan C. , Scanlon Micheál D. , Méndez Manuel A. , Peljo Pekka , Opallo Marcin , Girault Hubert H.
Published: June 2016

The water oxidation process in acidified water/acetonitrile mixtures was studied by cyclic voltammetry using fluorinated tin oxide (FTO) electrodes modified layer‐by‐layer with deposited bilayers of positively charged poly(diallyldimethylammonium chloride) (PDDA) polymer and negatively charged citrate‐stabilized iridium oxide (IrO2) nanoparticles. The voltammetric profiles obtained at high water contents resemble those in aqueous media and remain approximately unchanged. However, as the water content decreases below a water mole fraction (XH2O) of 0.6, a tipping point is reached and the onset potential for water oxidation gradually decreases. This reflects an enhanced reactivity, and therefore lower overpotential, of water molecules towards oxidation in water/acetonitrile mixtures. These lower kinetic barriers towards water oxidation are rationalized based on the degradation of the hydrogen bond network upon the formation of water/acetonitrile mixtures. Thus, as the ice‐like structure of neat water transitions to clusters and low‐bonded oligomers, these water molecules in more “free” states exhibit an enhanced susceptibility to water oxidation.
Effective Electrochemical Sterilization Based on Electrocatalysis of Oxygen Reduction by Multiwalled Carbon Nanotubes
Authors: Li Zheng‐Hong , You Shi‐Jie , Gong Xiao‐Bo , Wan Xiao‐Yun , Ren Nan‐Qi
Published: June 2016

Disinfection of drinking water is crucial for protecting the public from disease. It is therefore important to develop high‐efficiency, low‐cost and byproduct‐free technology for the effective deactivation of organisms or pathogens in water. A study on electrochemical disinfection based on the oxygen reduction reaction (ORR) catalyzed by multiwalled carbon nanotubes (MWCNTs) is reported. MWCNTs demonstrated higher activity and comparable selectivity compared with carbon blacks toward two‐electron ORR with the formation of hydrogen peroxide. By optimizing the operating conditions (pH 7.0, 50 mmol L−1 phosphate buffer concentration, current density 15 mA cm−2), a sterilization efficiency of 99.9 % toward E. coli is achieved following electrolysis for 15 min. The oxidative species attack the cell wall of E. coli, leading to the bursting of the cell membrane and the isolation of intracellular components. Based on electrochemical disinfection driven by two‐electron ORR on MWCNTs, microorganisms are removed with an efficiency of 99.9 % from the effluent of secondary clarification from a municipal wastewater treatment plant. Owing to lower energy consumption for the ORR at lower potential, this study provides a proof‐of‐concept demonstration of a more effective method for disinfection.
Restraining Capacity Increase To Achieve Ultrastable Lithium Storage: Case Study of a Manganese(II) Oxide/Graphene‐Based Nanohybrid and Its Full‐Cell Performance
Authors: Liu Dai‐Huo , Li Wei , Wan Fang , Fan Chao‐Ying , Wang Ying‐Ying , Zhang Lin‐Lin , Lü Hong‐Yan , Xing Yue‐Ming , Zhang Xiao‐Hua , Wu Xing‐Long
Published: June 2016

As is well known, a gradual increase in capacity during cycling is a common phenomenon in previously reported oxide‐based anodes for lithium‐ion batteries. However, not only may this be superfluous for practical applications, but it may also imply the presence of some electrochemical instabilities and side reactions. To achieve ultrastable Li storage without such a gradual increase in capacity, the mechanism of this increase by using a MnO/graphene‐based nanohybrid (MnO@C/RGO) as an example was comprehensively explored. Then, the gradual increase behavior of the specific capacity was effectively restrained by rationally optimizing the cutoff voltage, which resulted in the MnO@C/RGO electrode maintaining a nearly constant capacity during cycling at different current densities. Taking the high current density of 2 A g−1 as an example, there was no clear capacity change (increase/attenuation) even over 2000 cycles with stable coulombic efficiencies of around 99.7 %. This ultrastable Li‐storage capability should mainly benefit from rational testing parameters and an optimal 3D conductive network. More importantly and interestingly, full cells were also assembled and tested by coupling MnO@C/RGO and commercial LiFePO4 as the anode and cathode materials, respectively. The full cells impressively exhibited superior rate performance and excellent cycling stability.
Analyzing Electrochemiluminescence Mechanisms of Thiophene–Triazole–Thiophene Luminophores with In Situ Spectroscopy
Authors: Li Michelle S. M. , Chu Kenneth , Price Jacquelyn T. , Jones Nathan D. , Ding Zhifeng
Published: June 2016

Herein, we report the electrochemical and electrochemiluminescence (ECL) study of thiophene luminophores, 1‐[2,2′]bithiophenyl‐4‐yl‐4‐thiophen‐2‐yl‐1H‐[1,2,3]triazole (TTT) and 4‐thiophen‐2‐yl‐1‐thiophen‐3‐yl‐1H‐[1,2,3]triazole (TT), in N,N‐dimethylformamide (DMF). Differential pulse voltammetry was used to determine the oxidation and reduction potentials of the two compounds. TTT and TT in DMF exhibited relatively weak ECL efficiencies following the annihilation mechanism. However, ECL was enhanced with co‐reactants, persulfate, benzoyl peroxide, and tri‐n‐propylamine. In these experiments, TTT displayed stronger ECL activity than TT, due to the quasireversible nature of the reduction reactions. Spooling ECL spectroscopy was utilized to gain analytical insight into light‐emission mechanisms. It was shown that whereas these two thiophene compounds could form photoinduced excited monomers, excimers were generated mainly in their co‐reactant ECL paths.
Engineering Porous Organic Cage Crystals with Increased Acid Gas Resistance
Authors: Zhu Guanghui , Hoffman Christopher D. , Liu Yang , Bhattacharyya Souryadeep , Tumuluri Uma , Jue Melinda L. , Wu Zili , Sholl David S. , Nair Sankar , Jones Christopher W. , Lively Ryan P.
Published: June 2016

Both known and new CC3‐based porous organic cages are prepared and exposed to acidic SO2 in vapor and liquid conditions. Distinct differences in the stability of the CC3 cages exist depending on the chirality of the diamine linkers used. The acid catalyzed CC3 degradation mechanism is probed via in situ IR and a degradation pathway is proposed and supported with computational results. CC3 crystals synthesized with racemic mixtures of diaminocyclohexane exhibited enhanced stability compared to CC3‐R and CC3‐S. Confocal fluorescent microscope images reveal that the stability difference in CC3 species originates from an abundance of mesoporous grain boundaries in CC3‐R and CC3‐S, allowing facile access of aqueous SO2 throughout the crystal, promoting decomposition. These grain boundaries are absent from CC3 crystals made with racemic linkers.
Porous Mn2O3: A Low‐Cost Electrocatalyst for Oxygen Reduction Reaction in Alkaline Media with Comparable Activity to Pt/C
Authors: Wang Wenhai , Geng Jing , Kuai Long , Li Min , Geng Baoyou
Published: June 2016

Preparing nonprecious metal catalysts with high activity in the oxygen reduction reaction (ORR) can promote the development of energy conversion devices. Support‐free porous Mn2O3 was synthesized by a facile aerosol‐spray‐assisted approach (ASAA) and subsequent thermal treatment, and exhibited ORR activity that is comparable to commercial Pt/C The catalyst also exhibits notably higher activity than other Mn‐based oxides, such as Mn3O4 and MnO2. The rotating ring disk electrode (RRDE) study indicates a typical 4‐electron ORR pathway on Mn2O3. Furthermore, the porous Mn2O3 demonstrates considerable stability and a good methanol tolerance in alkaline media. In light of the low cost and high earth abundance of Mn, the highly active Mn2O3 is a promising candidate to be used as a cathode material in metal–air batteries and alkaline fuel cells.
ChemInform Abstract: Synthesis, Single‐Crystal Structure Determination and Raman Spectra of the Tricyanomelaminates NaA5 [C6N9]2·4H2O (A: Rb, Cs).
Authors: Reckeweg Olaf , Schulz Armin , DiSalvo Francis J.
Published: June 2016

Transparent colorless crystals of the title compounds are prepared from of solutions of Na3[C6N9] and RbF or CsF in boiling water by slow evaporation at room temperature.
ChemInform Abstract: Stabilization of 3d Transition Metal Hydrido Complexes in SrH2Mg2[Co(I)H5], BaH2Mg5[Co(‐I)H4]2, and RbH2Mg5[Co(‐I)H4Ni(0)H4] via Easily Polarizable Hydride Ligands.
Authors: Fahlquist Henrik , Moser David , Noreus Dag , Refson Keith , Parker Stewart F.
Published: June 2016

The structure and bonding of the new title compounds are characterized by powder XRD, neutron diffraction, inelastic neutron scattering, and DFT calculations.
ChemInform Abstract: Michael Addition Catalyzed by Difluorotris(pentafluoroethyl)phosphorane.
Authors: Bittner Bozena , Koppe Karsten , Frank Walter , Ignat'ev Nikolai
Published: June 2016

Michael addition reactions of 1,3‐diketones or β‐ketoesters (Michael donors) with linear or cyclic unsaturated ketones (Michael acceptors) to give Michael products with moderate to high yields under mild reaction conditions are carried out.
ChemInform Abstract: Iridium‐Catalyzed Asymmetric Allylic Substitutions with Bulky Amines/Oxidative Double Bond Cleavage — Entry into the Reetz Synthesis of Amino Alcohols.
Authors: Seehafer Kai , Malakar Chandi C. , Bender Markus , Qu Jianping , Liang Chen , Helmchen Guenter
Published: June 2016

Branched allylic amines are synthesized and transformed into N‐protected amino aldehydes.
ChemInform Abstract: From Protected‐Hydroxy Acylsilanes to Functionalized Silyl Enol Ethers and Applications in Mukaiyama Aldol Reactions.
Authors: Ruiz Johal , Karre Nagaraju , Roisnel Thierry , Chandrasekhar Srivari , Gree Rene
Published: June 2016

The reaction of protected β‐hydroxy acylsilanes (I) and (XII) with sulfones provides (E)‐silyl enol ethers, whereas the reaction with Grignard reagent (V) give the (Z)‐isomers (VI) as sole products.
ChemInform Abstract: Penta‐2,4‐dien‐1‐ones by Formal [3 + 2] Cycloaddition‐Rearrangement of Electron‐Deficient Diethyl 2‐(Dicyanomethylene)malonate with Alkynes.
Authors: Donckele Etienne J. , Reekie Tristan A. , Trapp Nils , Diederich Francois
Published: June 2016

The title reaction proceeds with excellent regioselectivity under catalyst free conditions.
ChemInform Abstract: Phosphanamine‐Functionalized Magnetic Nanoparticles (PAFMNP): An Efficient Magnetic Recyclable Ligand for the Pd‐Catalyzed Heck Reaction of Chloroarenes.
Authors: Panahi Farhad , Zarnaghash Narges , Khalafi‐Nezhad Ali
Published: June 2016

Heck reaction of chloroarenes (I) with vinyl compounds (II) is accomplished using title nanoparticles as catalyst.
ChemInform Abstract: Enantioselective Construction of Aryl‐Substituted All‐Carbon Quaternary Stereocenters by Using Tertiary Amine‐Thiourea‐Catalyzed Michael Additions.
Authors: Chen Peng , Bao Xu , Zhang Le‐Fen , Liu Guo‐Jie , Jiang Yi‐Jun
Published: June 2016

Michael addition of α‐cyanoketones and acrylates in the presence of chiral cinchonidine catalyst (CJN) produces the corresponding Michael adducts in high yields with moderate to good enantioselectivities.
ChemInform Abstract: Metal Free Bi(hetero)aryl Synthesis: A Benzyne Truce—Smiles Rearrangement.
Authors: Holden Catherine M. , Sohel Shariar M. A. , Greaney Michael F.
Published: June 2016

A new benzyne transformation is described that affords versatile biaryl structures without using any transition‐metal catalysts or organometallic building blocks.
ChemInform Abstract: Gold‐Catalyzed Intramolecular Tandem Cyclization of Indole‐Ynamides: Diastereoselective Synthesis of Spirocyclic Pyrrolidinoindolines.
Authors: Zheng Nan , Chang Yuan‐Yuan , Zhang Li‐Jie , Gong Jian‐Xian , Yang Zhen
Published: June 2016

Tetracyclic spirocyclic pyrrolidinoindolines bearing an all‐carbon quaternary stereocenter are synthesized in a single step under mild reaction conditions.
ChemInform Abstract: One‐Pot Transformation of Aliphatic Carboxylic Acids into N‐Alkylsuccinimides with NIS and NCS/NaI.
Authors: Nakai Yuhta , Moriyama Katsuhiko , Togo Hideo
Published: June 2016

Treatment of acids (I) with NIS affords the corresponding alkyl iodides.
ChemInform Abstract: Synthesis and Cytotoxicity Evaluation of New 3‐Substituted 4‐(4‐Methyloxy phenyl)‐1H‐pyrrole Derivatives.
Authors: Zhan Xiaoping , Lan Lan , Zhang Yuankui , Chen Jian , Zhao Kai , Wang Shuai , Xin Yuxuan , Mao Zhenmin
Published: June 2016

The title compounds (V) exhibit a broad‐spectrum of anticancer activities.
ChemInform Abstract: Construction of 3‐Amino‐2‐oxindoles by Direct Amination of Aniline or α‐Amino‐Acid Derivatives to 3‐Bromooxindoles.
Authors: Zhao Min , Li Nai‐Kai , Zhang Ya‐Fei , Pan Feng‐Feng , Wang Xing‐Wang
Published: June 2016

The Ni‐catalyzed asymmetric amination of 3‐bromooxindoles with anilines is developed.
ChemInform Abstract: Synthesis of Angularly Fused (Homo)triquinane‐Type Hydantoins as Precursors of Bicyclic Prolines.
Authors: Smit Biljana , Rodic Marko , Pavlovic Radoslav Z.
Published: June 2016

The title hydantoins are synthesized involving a highly diastereoselective Bucherer—Bergs reaction of alkenylcycloalkanones followed by a regioselective selenium‐induced closure of a pyrrolidine ring.
ChemInform Abstract: Four‐Component Synthesis of Pyrano[2,3‐c]pyrazoles Catalyzed by Triphenylphosphine in Aqueous Medium
Authors: Amine Khodja Imene , Fisli Amina , Lebhour Oumeima , Boulcina Raouf , Boumoud Boudjemaa , Debache Abdelmadjid
Published: June 2016

starting from hydrazine/phenylhydrazine, ethyl acetoacetate, malononitrile, and various aromatic or heteroaromatic aldehydes
ChemInform Abstract: Magnetically Separable Iron Oxide Nanoparticles: An Efficient and Reusable Catalyst for Imino Diels—Alder Reaction
Authors: Basavegowda Nagaraj , Mishra Kanchan , Lee Yong Rok , Joh Young‐Gull
Published: June 2016

providing efficient access to a variety of substituted 2‐methyltetrahydroquinoline derivatives
ChemInform Abstract: Synthesis of Substituted Quinolizidines via a Gold‐Catalyzed Double Cyclization Cascade.
Authors: Nonaka Shiori , Sugimoto Kenji , Ueda Hirofumi , Tokuyama Hidetoshi
Published: June 2016

A novel synthesis of quinolizidines by a cationic gold‐catalyzed double cyclization cascade is reported.
ChemInform Abstract: 1,2‐Hydride Migration in Dialkyl α‐Diazophosphonates Catalyzed by [Cu(MeCN)4]PF6: A Novel Approach to β‐Amino (E)‐Enylphosphonates.
Authors: Ge Haihong , Liu Shuang , Cai Yan , Sun Yuchao , Miao Zhiwei
Published: June 2016

Steric factors are found to influence the E/Z isomer selectivity in the synthesis of the title phosphonates.
ChemInform Abstract: Constraining the Coordination Geometries of Lanthanide Centers and Magnetic Building Blocks in Frameworks: A New Strategy for Molecular Nanomagnets
Authors: Liu Ke , Zhang Xuejing , Meng Xixi , Shi Wei , Cheng Peng , Powell Annie K.
Published: June 2016

Review: 50 refs.
ChemInform Abstract: Transition Metal‐Catalyzed Carbonylative C—H Bond Functionalization of Arenes and C(sp3)—H Bond of Alkanes
Authors: Gadge Sandip T. , Gautam Prashant , Bhanage Bhalchandra M.
Published: June 2016

Review: [70 refs.
ChemInform Abstract: Synthetic Reactions Using Low‐Valent Titanium Reagents Derived from Ti(OR)4 or CpTiX3 (X: O‐iPr or Cl) in the Presence of Me3SiCl and Mg
Authors: Okamoto Sentaro
Published: June 2016

Review: [34 refs.
ChemInform Abstract: Metal—Organic Framework (MOF) Compounds: Photocatalysts for Redox Reactions and Solar Fuel Production
Authors: Dhakshinamoorthy Amarajothi , Asiri Abdullah M. , Garcia Hermenegildo
Published: June 2016

Review: 148 refs.
ChemInform Abstract: Phosphoric Acid Based Heterodimers in Asymmetric Catalysis
Authors: Monaco Mattia R. , Pupo Gabriele , List Benjamin
Published: June 2016

Review: [59 refs.
ChemInform Abstract: γ‐AApeptides as a New Class of Peptidomimetics
Authors: Teng Peng , Shi Yan , Sang Peng , Cai Jianfeng
Published: June 2016

Review: research outcomes of γ‐AApeptides and a future perspective; 26 refs.
ChemInform Abstract: Construction of Homogeneous Antibody—Drug Conjugates Using Site‐Selective Protein Chemistry
Authors: Akkapeddi Padma , Azizi Saara‐Anne , Freedy Allyson M. , Cal Pedro M. S. D. , Gois Pedro M. P. , Bernardes Goncalo J. L.
Published: June 2016

Review: 98 refs.
ChemInform Abstract: Breakdown of Chlorophyll in Higher Plants—Phyllobilins as Abundant, Yet Hardly Visible Signs of Ripening, Senescence, and Cell Death
Authors: Kraeutler Bernhard
Published: June 2016

Review: [126 refs.
Exploring the link between management communication and emotions in mergers and acquisitions
Authors: Zagelmeyer Stefan , Sinkovics Rudolf R. , Sinkovics Noemi , Kusstatscher Verena
Published: June 2016

News on merger and acquisition (M&A) activities frequently dominate the popular business press. While the announcement of an M&A usually elicits enthusiasm in the business community, it also results in increased levels of uncertainty, stress, and anxiety for employees. Based on a qualitative analysis of four international M&A cases, this paper integrates emotions and communication during mergers and acquisitions in a conceptual framework. We argue that management communication and information flows during all stages of an M&A process represent affective events, which in a cognitive appraisal process trigger positive and negative emotions. These in turn may influence employee attitudes, behaviour, and performance, and ultimately also M&A success. Copyright © 2016 ASAC. Published by John Wiley & Sons, Ltd.
Comparison of Risk Prediction With the CKD‐EPI and MDRD Equations in Non–ST‐Segment Elevation Acute Coronary Syndrome
Authors: Flores‐Blanco Pedro J. , López‐Cuenca Ángel , Januzzi James L. , Marín Francisco , Sánchez‐Martínez Marianela , Quintana‐Giner Miriam , Romero‐Aniorte Ana I. , Valdés Mariano , Manzano‐Fernández Sergio
Published: June 2016

Background

Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) equations estimate glomerular filtration rate (GFR) more accurately than the Modification of Diet in Renal Disease (MDRD) equation.

Hypothesis

New CKD‐EPI equations improve risk stratification in patients with non‐ST‐segment elevation acute coronary syndrome (NSTE‐ACS) and provide complementary information to the Global Registry of Acute Coronary Events (GRACE) risk score.

Methods

We studied 350 subjects (mean age, 68 ± 12 years; 70% male) with NSTE‐ACS. Estimated GFR was calculated using the MDRD and new CKD‐EPI equations based on serum creatinine (SCr) and/or cystatin C (CysC) concentrations obtained within 48 hours of hospital admission. The primary endpoint was all‐cause death during follow‐up.

Results

Over the study period (median, 648 days [interquartile range, 236–1042 days]), 31 patients died (0.05% events per person‐year). Decedents had poorer renal‐function parameters (P < 0.001). Both CysC‐based CKD‐EPI equations had the highest areas under the receiver operating characteristic curve for the prediction of all‐cause mortality. After multivariate adjustment, only CysC‐based CKD‐EPI equations were independent predictors of all‐cause mortality (CKD‐EPISCr‐CysC, per mL/min/1.73 m2: hazard ratio: 0.975, 95% confidence interval: 0.956‐0.994, P = 0.009; CKD‐EPICysC, per mL/min/1.73 m2: hazard ratio: 0.976, 95% confidence interval: 0.959‐0.993, P = 0.005). Reclassification analyses showed that only CysC‐based CKD‐EPI equations improved predictive accuracy of the GRACE risk score.

Conclusions

In patients with NSTE‐ACS, CysC‐based CKD‐EPI equations improved clinical risk stratification for mortality and added complementary prognostic information to the GRACE risk score.
Improving the patient experience in the delivery of high quality surgical care and health outcomes
Authors: Kim Simon P. , Abouassaly Robert
Published: June 2016

With passage of the Patient Protection and Affordable Care Act, the Centers for Medicare and Medicaid Services have placed a greater degree of emphasis on value for health care delivery by focusing on improving health outcomes and quality and lowering costs. In this issue of Cancer, Shirk et al examine the relationship between the patient‐centered experience and hospital outcomes for patients undergoing radical prostatectomy, nephrectomy, and cystectomy for genitourinary malignancies.

See also pages 2571‐8.
Liquid Exfoliation of Layered Transition Metal Dichalcogenides for Biological Applications
Authors: Nguyen Emily P. , Daeneke Torben , Zhuiykov Serge , Kalantar‐zadeh Kourosh
Published: June 2016

Known to possess distinctive properties that differ greatly from their bulk form, layered two‐dimensional materials have been extensively studied and incorporated into many versatile applications ranging from optoelectronics to sensors. For biomedical research, two‐dimensional transition metal dichalcogenides (2D TMDs) have garnered much interest as they have been shown to exhibit relatively low toxicity, high stability in aqueous environments, and the ability to adhere to biological materials such as proteins. These materials are promising candidates, demonstrating potential applications in biosensing, cell imaging, diagnostics, and therapeutics. Preparation and exfoliation of 2D TMDs play an important part in these various applications as their properties are heavily dependent on the number of layers and lateral size. Described in this article are protocols for the liquid exfoliation of 2D TMDs from their bulk materials. Additional protocols are also provided for functionalizing or modifying the surface of the exfoliated 2D TMDs. © 2016 by John Wiley & Sons, Inc.
Assays for Determination of Protein Concentration
Authors: Olson Bradley J.S.C.
Published: June 2016

Biochemical analysis of proteins relies on accurate quantification of protein concentration. Detailed in this appendix are some commonly used methods for protein analysis, e.g., Lowry, Bradford, bicinchoninic acid (BCA), UV spectroscopic, and 3‐(4‐carboxybenzoyl)quinoline‐2‐carboxaldehyde (CBQCA) assays. The primary focus of this report is assay selection, emphasizing sample and buffer compatibility. The fundamentals of generating protein assay standard curves and of data processing are considered, as are high‐throughput adaptations of the more commonly used protein assays. Also included is a rapid, inexpensive, and reliable BCA assay of total protein in SDS‐PAGE sample buffer that is used for equal loading of SDS‐PAGE gels. © 2016 by John Wiley & Sons, Inc.
Association and Diffusion of Li+ in Carboxymethylcellulose Solutions for Environmentally Friendly Li‐ion Batteries
Authors: Casalegno Mosè , Castiglione Franca , Passarello Marco , Mele Andrea , Passerini Stefano , Raos Guido
Published: June 2016

Carboxymethylcellulose (CMC) has been proposed as a polymeric binder for electrodes in environmentally friendly Li‐ion batteries. Its physical properties and interaction with Li+ ions in water are interesting not only from the point of view of electrode preparation—processability in water is one of the main reasons for its environmental friendliness—but also for its possible application in aqueous Li‐ion batteries. We combine molecular dynamics simulations and variable‐time pulsed field gradient spin‐echo (PFGSE) NMR spectroscopy to investigate Li+ transport in CMC‐based solutions. Both the simulations and experimental results show that, at concentrations at which Li‐CMC has a gel‐like consistency, the Li+ diffusion coefficient is still very close to that in water. These Li+ ions interact preferentially with the carboxylate groups of CMC, giving rise to a rich variety of coordination patterns. However, the diffusion of Li+ in these systems is essentially unrestricted, with a fast, nanosecond‐scale exchange of the ions between CMC and the aqueous environment.
Determination of Interfacial Charge‐Transfer Rate Constants in Perovskite Solar Cells
Authors: Pydzińska Katarzyna , Karolczak Jerzy , Kosta Ivet , Tena‐Zaera Ramon , Todinova Anna , Idígoras Jesus , Anta Juan A. , Ziółek Marcin
Published: June 2016

A simple protocol to study the dynamics of charge transfer to selective contacts in perovskite solar cells, based on time‐resolved laser spectroscopy studies, in which the effect of bimolecular electron–hole recombination has been eliminated, is proposed. Through the proposed procedure, the interfacial charge‐transfer rate constants from methylammonium lead iodide perovskite to different contact materials can be determined. Hole transfer is faster for CuSCN (rate constant 0.20 ns−1) than that for 2,2′,7,7′‐tetrakis‐(N,N‐di‐4‐methoxyphenylamino)‐9,9′‐spirobifluorene (spiro‐OMeTAD; 0.06 ns−1), and electron transfer is faster for mesoporous (0.11 ns−1) than that for compact (0.02 ns−1) TiO2 layers. Despite more rapid charge separation, the photovoltaic performance of CuSCN cells is worse than that of spiro‐OMeTAD cells; this is explained by faster charge recombination in CuSCN cells, as revealed by impedance spectroscopy. The proposed direction of studies should be one of the key strategies to explore efficient hole‐selective contacts as an alternative to spiro‐OMeTAD.
Study of Pyridine‐Mediated Electrochemical Reduction of CO2 to Methanol at High CO2 Pressure
Authors: Rybchenko Sergey I. , Touhami Dalila , Wadhawan Jay D. , Haywood Stephanie K.
Published: June 2016

The recently proposed highly efficient route of pyridine‐catalyzed CO2 reduction to methanol was explored on platinum electrodes at high CO2 pressure. At 55 bar (5.5 MPa) of CO2, the bulk electrolysis in both potentiostatic and galvanostatic regimes resulted in methanol production with Faradaic yields of up to 10 % for the first 5–10 C cm−2 of charge passed. For longer electrolysis, the methanol concentration failed to increase proportionally and was limited to sub‐ppm levels irrespective of biasing conditions and pyridine concentration. This limitation cannot be removed by electrode reactivation and/or pre‐electrolysis and appears to be an inherent feature of the reduction process. In agreement with bulk electrolysis findings, the CV analysis supported by simulation indicated that hydrogen evolution is still the dominant electrode reaction in pyridine‐containing electrolyte solution, even with an excess CO2 concentration in the solution. No prominent contribution from either a direct or coupled CO2 reduction was found. The results obtained suggest that the reduction of CO2 to methanol is a transient process that is largely decoupled from the electrode charge transfer.
Movement in the matrix: substrates and distance‐to‐forest edge affect postmetamorphic movements of a forest amphibian
Authors: Cline Brittany B. , Hunter Malcolm L.
Published: June 2016

Population persistence often depends on functional connectivity for animals that transit multiple vegetation types to acquire resources, particularly for dispersers navigating a landscape matrix fragmented by agriculture, forestry, or urbanization. For many pool‐breeding amphibians, population viability depends on the ability of juveniles to locate and reach suitable habitat in the terrestrial matrix. Thus, identifying the scale and orientation of movements is necessary to predict the consequences of landscape configuration for populations. We conducted three experiments to evaluate if different vegetation types alter the behavior of post‐metamorphic wood frogs (Lithobates sylvaticus). We measured the: (1) fine‐scale movement (velocity, latency, path length, net displacement, path tortuosity, and orientation) of individuals (n = 150) released on five substrates (asphalt, corn, forest leaf litter, hay, lawn); (2) directionality of frogs (n = 168) released at different distances from forest in two open‐cover types (lawns, hayfields); and (3) willingness of frogs (n = 240) to enter three land‐cover types (asphalt, lawn, forest) when released within artificial refugia islands at different distances from forest. Using fluorescent powder, we mapped 318 movement paths and performance differed. Frogs demonstrated straighter paths, and greater net movements, path lengths, and velocities through treatments with lower structural complexity (asphalt > lawn > corn > forest leaf litter > hay). Frogs also exhibited forest‐oriented directionality in asphalt, lawn, and corn but random orientation in forest control and hay. The willingness of individuals to leave a refugia island was lowest on asphalt (12% of released frogs), moderate on lawn (40%), and very high in forest (90%). Overall, results indicate that the quality of nonforest matrix may influence the ability of frogs to traverse open cover and orient toward forest from distances of ≥40–55 m. Thus, it is inaccurate to assume movement performance is uniform across all open‐matrix types, an important distinction because many landscape‐population models use expert‐based values that are a one‐size‐fits‐all measure for open cover. Our study provides field‐based, mechanistic approximations of juvenile movement that can be useful for predicting how matrix composition and configuration might be managed to maintain or restore functional connectivity.
Testing epidemiological functional groups as predictors of avian haemosporidia patterns in southern Africa
Authors: Hellard Eléonore , Cumming Graeme S. , Caron Alexandre , Coe Elizabeth , Peters Jeffrey L.
Published: June 2016

Understanding the dynamics of multihost parasites and the roles of different host species in parasite epidemiology requires consideration of the whole animal community. Host communities may be composed of hundreds of interacting species, making it necessary to simplify the problem. One approach to summarizing the host community in a way that is relevant to the epidemiology of the parasite is to group host species into epidemiological functional groups (EpiFGs). We used EpiFGs to test our understanding of avian malaria (PlasmodiumandHaemoproteus) dynamics in four communities of wetland‐associated birds in southern Africa. Bird counts and captures were undertaken every 2–4 months over 2 yr and malaria was diagnosed by nestedPCR. One hundred and seventy‐six bird species were allocated to a set of EpiFGs according to their assumed roles in introducing and maintaining the parasite in the system. Roles were quantified as relative risks from avian foraging, roosting, and movement ecology and assumed interaction with vector species. We compared our estimated a priori risks to empirical data from 3414 captured birds from four sites and 3485 half‐hour point counts. After accounting for relative avian abundance, our risk estimates significantly correlated with the observed prevalence ofHaemoproteusbut notPlasmodium. Although avian roosting height (for both malarial genera) and movement ecology (forPlasmodium) separately influenced prevalence, host behavior alone was not sufficient to predictPlasmodiumpatterns in our communities. Host taxonomy and relative abundance were also important for this parasite. Although using EpiFGs enabled us to predict the infection patterns of only one genus of heamosporidia, our approach holds promise for examining the influence of host community composition on the transmission of vector‐borne parasites and identifying gaps in our understanding of host–parasite interactions.
Functional diversity of North American broad‐leaved trees is codetermined by past and current environmental factors
Authors: Ordonez Alejandro , Svenning Jens‐Christian
Published: June 2016

Modern and historical climate are known to codetermine broad‐scale species richness and composition patterns in temperate regions. Nonetheless, is poorly understood the extent to which these effects individually or in combination determine functional diversity, many studies have simply assumed equilibrium between current climate and functional diversity. We estimated functional richness (FRich) and dispersion (FDisp) of North American broad‐leaved trees by combining distribution and trait information. Then, we determined if contemporary water‐energy availability, current topographic variability, historical climatic stability, and lagged immigration from glacial refugia co‐determined the functional diversity of North American broad‐leaved trees. We did this by assessing the directionality, magnitude, and relative importance of various contemporary and historical environmental factors know to affect species diversity. Contrasts were performed across all North America (Mexico, United States, and Canada), and areas within this region that were glaciated or ice‐free during the Last Glacial Maximum (~21 000 yr ago). FRich and FDisp showed distinct geographic patterns that are strongly associated with both contemporary environmental conditions and glacial–interglacial climate change. Model averaged regression coefficients and AIC‐based variable relative importance estimates show that contemporary productivity (FRich‐wAIC: 1.0; FDisp‐wAIC: 1.0), annual precipitation (FRich‐wAIC: 0.81; FDisp‐wAIC: 1.0), and accessibility to glacial refugia (FRich‐wAIC: 0.92; FDisp‐wAIC: 1.0) have the strongest associations to FRich and FDisp. Furthermore, the association of functional diversity with topographic heterogeneity showed steeper slopes in ice‐free regions. These findings suggest that, contrary to the expectation climate‐diversity equilibrium, functional diversity of North America broad‐leaved trees is codetermined by current climate and lagged immigration from glacial refugia.
Implications of mechanistic modeling of drought effects on growth and competition in forest landscape models
Authors: Gustafson Eric J. , De Bruijn Arjan M. G. , Miranda Brian R. , Sturtevant Brian R.
Published: June 2016

The incidence of drought is expected to increase worldwide as a factor structuring forested landscapes. Ecophysiological mechanisms are being added to Forest Landscape Models (FLMs) to increase their robustness to the novel environmental conditions of the future (including drought), but their behavior has not been evaluated for mixed temperate forests. We evaluated such an approach by assessing the ability of physiological mechanisms to predict susceptibility to tree mortality as a function of drought in the upper Midwest (USA) through controlled site‐level drought simulation experiments using the PnET‐Succession extension of the LANDIS‐II FLM. We also conducted a landscape‐level experiment to study landscape response to drought treatments in the presence of the spatial processes of seed dispersal and stand‐replacing disturbance. At the site level we found that net photosynthesis and carbon reserves showed a clear negative response to both the length of drought and the alternating pulses of normal precipitation and drought events, with soils holding more water moderating this response. The effect of the drought treatments varied somewhat depending on the assemblage of competitors and their specific life‐history traits such as ability to compete for light, maximum photosynthetic capacity and water use efficiency. A large diversity of assemblages were simulated at the landscape level, and species abundance generally sorted by photosynthetic capacity (foliar nitrogen) and life form (deciduous vs. evergreen), with faster growing species and deciduous species suffering less decline because of drought. Soil type also had an impact on total productivity (biomass), with soils having higher available water being more productive through time. We conclude that (1) the mechanistic, first principles approach is advantageous for global change research because the combination of life‐history traits of competitors interact to cause a site‐specific dynamic response to fundamental drivers (e.g., precipitation, temperature), and these site‐level responses interact spatially to create landscape responses that are complex and difficult to project with less mechanistic approaches, and (2) published findings that increasing drought length (rather than severity) increases tree mortality in the upper Midwest are clearly consistent with a mechanism of acute photosynthetic depression resulting in increased likelihood of carbon starvation as droughts lengthen.
Population coherence and environmental impacts across spatial scales: a case study of Chinook salmon
Authors: Ohlberger Jan , Scheuerell Mark D. , Schindler Daniel E.
Published: June 2016

A central problem in understanding how species respond to global change is in parsing the effects of local drivers of population dynamics from regional and global drivers that are shared among populations. Management and conservation efforts that typically focus on a particular population would benefit greatly from being able to separate the effects of environmental processes at local, regional, and global scales. One way of addressing this challenge is to integrate data across multiple populations and use multivariate time series approaches to estimate shared and independent components of dynamics among neighboring populations. Here, we use a data set of 15 populations of Chinook salmon (Oncorhynchus tshawytscha) covering a broad geographical range in the eastern North Pacific Ocean to show how Dynamic Factor Analysis (DFA) can be used to estimate temporal coherence in population dynamics and to detect environmental drivers across spatial scales. Our results show that productivity dynamics of Chinook salmon populations strongly covary at the regional scale, but to a lesser degree at larger spatial scales. The timing of river ice break‐up in spring was identified as an important driver of regional productivity dynamics. In addition, broad‐scale variability in population productivity was linked to the North Pacific Gyre Oscillation, a dominant pattern of sea surface height variability. These broad‐scale patterns in productivity dynamics may be associated with recent regime shifts in the Northeast Pacific Ocean. However, our results also demonstrate that populations within regions do not always respond consistently to the same environmental drivers, thus suggesting location‐specific impacts. Overall, this study illustrates the use of DFA for quantifying the spatial and temporal complexity of multiple population responses to environmental change, thereby providing insights to processes that affect populations across large geographic areas, but that might be filtered by local habitat conditions.
Livestock tracks transform resource distribution on terracette landscapes of the Loess Plateau
Authors: Jin Baocheng , Sun Guojun , Zhang Ying , Zou Mei , Ni Xiaofeng , Luo Kai , Zhang Xueli , Cheng Hua , Li Fengmin , Wu X. Ben
Published: June 2016

Striking networks of livestock tracks, or terracettes, molded to the contours are a common feature on hilly rangelands of the semiarid Loess Plateau, one of the regions with the most severe soil erosion in the world. The formation of livestock tracks results in modified micro‐topography and ecological processes and leads to strong patterns in spatial distribution of vegetation, water, and nutrients. We investigated the spatial pattern of the topo‐edaphic, hydrological, biogeochemical, and biological attributes of these terracette landscapes and explored their potential implications to ecosystem functions. The results showed strong spatial heterogeneity in topo‐edaphic and biological structure of these landscapes, organized with three segments of a basic landscape unit—track, shoulder, and interslope. The above‐ and below‐ground biomass and soil nutrients concentrated in the shoulder segment forming a “band of fertility”. The network of livestock tracks likely reduced surface runoff and erosion by intercepting runoff and facilitate infiltration, while posing little risk of increasing shallow slope failures given the structure of loess soil. There appears a positive feedback loop for maintaining the structure of terracette landscapes. Trampling by goats maintains the tracks, which leads to spatial heterogeneity in biophysical structure and processes. The network of tracks enabled the goats to travel and graze in ways that reduce energy expenditure and increase foraging efficiency, which leads to strongly preferential use of the tracks by the goats. There are also evidence of a possible process resemble a slope parallel retreat at a micro‐scale, which may result in upslope movement of the terracettes. There may be important functional differences between landscapes with and without networks of livestock tracks, in regulating water runoff and soil erosion, forage production, and soil carbon storage. These functional differences may have significant implications to land use policies and practices aiming at soil and water conservation and socioecological sustainability of the Loess Plateau.
Bad neighbors: how spatially disjunct habitat degradation can cause system‐wide population collapse
Authors: Noonburg Erik G. , Byers James E.
Published: June 2016

Movement of individuals links the effects of local variation in habitat quality with growth and persistence of populations at the landscape scale. When the populations themselves are linked by interspecific interactions, such as predation, differential movement between habitats may lead to counterintuitive system‐wide dynamics. Understanding the interaction between local drivers and dynamics of widely dispersed species is necessary to predict the impacts of habitat fragmentation and degradation, which may be transmitted across habitat boundaries by species' movements. Here we model predator–prey interactions across unaltered and degraded habitat areas, and we explore the additional effects of adaptive habitat choice by predators on the resilience of prey populations. We show how movement between habitats can produce the “bad neighbor effect,” in which predators' response to localized habitat degradation causes system‐wide loss of prey populations. This effect arises because adaptive foraging results in the concentration of predators in the more productive unaltered habitat, even when this habitat can not support the increased prey mortality. The mechanisms underlying this effect are especially sensitive to prey dispersal rate and adaptive predator behavior.
Poly(vinylpylrrolidone) as Surfactant in the Sol–Gel Preparation of Lithium Iron Phospate/Carbon Cathodes for Lithium‐Ion Batteries
Authors: Fan Changling , Li Qiyuan , Chen Shilin , Fan Jiwei , Wen Zheng , Zeng Taotao , Zhang Xiang , Han Shaochang
Published: June 2016

Lithium iron phosphate/carbon (LiFePO4/C) is synthesized by a modified sol–gel method, in which the nonionic surfactant poly(vinylpyrrolidone) (PVP) is used. PVP plays a dual roles in the preparation of LiFePO4/C: it is used as surfactant to prevent the colloid particles and carbon source from aggregating, and is a carbon source. The carbon contents and conductivities of LiFePO4/C increase with increasing of PVP. When the ratio of PVP to LiFePO4 reaches 1 ‰, the conductivity of LiFePO4/C reaches its optimal value of 2.67×10−2 S cm−1 and its discharge capacity at 1 C is 131.0 mAh g−1. This is because the use of PVP leads particles that are small and have a homogeneous size distribution, which is due to dispersion by PVP. Titanium (Ti4+)‐doped samples, obtained from a sol–gel method, possess even better performances. The discharge capacities of this sample is 111.1 mAh g−1at 5 C and 87.3 mAh g−1 at 8 C. The gap in potential between the oxidative and reductive peaks is as low as 0.2053 V, which shows its reversibility is excellent.
Adverse effect of smoking on prognosis in human papillomavirus–associated oropharyngeal carcinoma
Authors: Liskamp Carmen P. , Janssens Geert O. , Bussink Johan , Melchers Willem J. , Kaanders Johannes H. , Verhoef Cornelia G.
Published: June 2016

Background

The purpose of this retrospective study was to identify prognostic factors in a cohort of patients with oropharyngeal carcinoma treated with intensity‐modulated radiotherapy (IMRT).

Methods

Medical records of 142 patients treated with (chemo)radiotherapy between September 2005 and September 2011 were reviewed and the human papillomavirus (HPV) status was determined by polymerase chain reaction (PCR) analysis. Potential prognostic factors for 3‐year locoregional control and overall survival (OS) were evaluated.

Results

HPV‐positive patients (n = 82) had locoregional control and OS of 78% and 79%, respectively. Significant prognostic factors on multivariate analysis were smoking (p = .03) for locoregional control and OS, and comorbidity (p = .04) for OS. Further stratification was done according to smoking behavior in HPV‐positive patients. Locoregional control in current smokers was 67% compared to 86% in never smokers and former smokers, respectively (p = .02).

Conclusion

Smoking was the only modifiable prognostic factor in HPV‐positive patients. Therefore, active stop‐smoking programs must be integrated in the routine management of patients to maximize treatment results. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1780–1787, 2016