bluuebunny/crossref_metadata_2025 huggingface dataset:
The investigation of thermal decomposition pathway and products of poly(vinyl alcohol) by TG‐FTIR
Authors: Taghizadeh Mohammad Taghi , Yeganeh Nazanin , Rezaei Mostafa
Published: March 2015

A generalized form of a semiquantitative method has been developed based on the multilinear least‐squares regression technique applied on the entire FTIR absorbance spectrum of a gaseous mixture to determine components concentration. Thermal degradation of poly(vinyl alcohol) samples with high, PVA(98), and low degree of hydrolysis, PVA(80), has been investigated by TG‐FTIR simultaneous analysis performed in an inert atmosphere. Analysis of gaseous products was carried out using a routine developed in Matlab and this routine returns the product concentration with a reasonable RMS error. The correlation coefficients of the original mixture spectrum with the mixed output were obtained at some specific peak temperatures using irAnalysis software. The first process is the loss of physically adsorbed water which followed by two main processes of thermal degradation. In spite of the similarity of evolved gaseous products, two samples showed some differences in components concentrations identified in the volatile mixture. Acetaldehyde has been identified as the main volatile product in the first thermal degradation step of PVA(98) and PVA(80). The second major degradation product of PVA(80) is acetic acid due to presence of more residual acetate group while 2‐butenal have been identified for PVA(98). Water was mainly produced in the first stage of thermal degradation of PVA(98) while it was identified in the first and second stages for PVA(80). This might be attributed to existence of a competition between water and residual acetate group for elimination that postpones the complete elimination of OH group to the second degradation stage. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42117.
Preparation of antibacterial silk fibroin membranes via tyrosinase‐catalyzed coupling of ε‐polylysine
Authors: Wang Ping , Deng Chao , Yuan Jiugang , Yu Yuanyuan , Cui Li , Su Mengting , Wang Qiang , Fan Xuerong
Published: March 2015

Silk fibroins have good biocompatibility and could be used to form a variety of regenerated functional biomaterials. In this study, enzymatic oxidization of silk fibroins with tyrosinase (TYR) was carried out, followed by coupling of ε‐polylysine (ε‐PLL) for improving antibacterial ability of the fibroin‐based biomaterial. Trinitrobenzene sulfonic acid (TNBS) was selectively used to incubate with silk fibroins prior to TYR treatment, aiming at preventing the self‐crosslinking of silk fibroins during enzymatic oxidation. The results indicated that tyrosine residues in silk fibroins could be converted to reactive dioxyphenylalanine and o‐quinone residues TYR successively. TNBS pretreatment inhibited the self‐crosslinks of silk fibroins and promoted the successive coupling of ε‐PLL to fibroin proteins with high graft yield. The combined use of TNBS, TYR, and ε‐PLL treatments endowed fibroin membrane with satisfactory antibacterial ability against Staphylococcus aureus, and the obtained durability was also acceptable. The changes in surface potential and amine acid composition for the fibroin membranes verified the favorable actions of the combined treatment. The present method could be potentially utilized for enzymatic functionalization of various fibroin‐based biomaterials.
High‐throughput microarray mapping of cell wall polymers in roots and tubers during the viscosity‐reducing process
Authors: Huang Yuhong , Willats William G. , Lange Lene , Jin Yanling , Fang Yang , Salmeán Armando A. , Pedersen Henriette L. , Busk Peter Kamp , Zhao Hai
Published: March 2015

Viscosity reduction has a great impact on the efficiency of ethanol production when using roots and tubers as feedstock. Plant cell wall–degrading enzymes have been successfully applied to overcome the challenges posed by high viscosity. However, the changes in cell wall polymers during the viscosity‐reducing process are poorly characterized. Comprehensive microarray polymer profiling, which is a high‐throughput microarray, was used for the first time to map changes in the cell wall polymers of sweet potato (Ipomoea batatas), cassava (Manihot esculenta), andCanna edulisKer. over the entire viscosity‐reducing process. The results indicated that the composition of cell wall polymers among these three roots and tubers was markedly different. The gel‐like matrix and glycoprotein network in theC. edulisKer. cell wall caused difficulty in viscosity reduction. The obvious viscosity reduction of the sweet potato and the cassava was attributed to the degradation of homogalacturonan and the released 1,4‐β‐d‐galactan and 1,5‐α‐l‐arabinan.
First approximation to congenital malformation rates in embryos and hatchlings of sea turtles
Authors: Bárcenas‐Ibarra Annelisse , de la Cueva Horacio , Rojas‐Lleonart Isaias , Abreu‐Grobois F. Alberto , Lozano‐Guzmán Rogelio Iván , Cuevas Eduardo , García‐Gasca Alejandra
Published: March 2015

Background

Congenital malformations in sea turtles have been considered sporadical. Research carried out in the Mexican Pacific revealed high levels of congenital malformations in the olive ridley, but little or no information is available for other species. We present results from analyses of external congenital malformations in olive ridley, green, and hawskbill sea turtles from Mexican rookeries on the Pacific coast and Gulf of Mexico.

METHODS

We examined 150 green and hawksbill nests and 209 olive ridley nests during the 2010 and 2012 nesting seasons, respectively. Olive ridley eggs were transferred to a hatchery and incubated in styrofoam boxes. Nests from the other two species were left in situ. Number of eggs, live and dead hatchlings, and eggs with or without embryonic development were registered. Malformation frequency was evaluated with indices of prevalence and severity.

Results

Mortality levels, prevalence and severity were higher in olive ridley than in hawksbill and green sea turtles. Sixty‐three types of congenital malformations were observed in embryos, and dead or live hatchlings. Of these, 38 are new reports; 35 for wild sea turtles, three for vertebrates. Thirty‐one types were found in hawksbill, 23 in green, and 59 in olive ridley. The head region showed a higher number of malformation types. Malformation levels in the olive ridley were higher than previously reported.

Conclusion

Olive ridleys seem more prone to the occurrence of congenital malformations than the other two species. Whether the observed malformation levels are normal or represent a health problem cannot be currently ascertained without long‐term assessments. Birth Defects Research (Part A) 103:203–224, 2015. © 2015 Wiley Periodicals, Inc.
Simultaneous measurement of methyl tert‐butyl ether and tert‐butyl alcohol in human serum by headspace solid‐phase microextraction gas chromatography–mass spectrometry
Authors: Zhang Rui , Mei Yong , Liu Yanru , Dai Hao , Xia Hongfang , Zhang Xin , Wu Yukang , Gu Yingying , Peng Xiaowu
Published: March 2015

The abundant production of methyl tert‐butyl ether (MTBE) and its widespread use have led to an increase in the potential for human exposure. This work described a simple, fast, sensitive, reliable and low‐cost method for the simultaneous measurement of MTBE and its metabolite, tert‐butyl alcohol (TBA) in human serum by headspace solid‐phase microextraction gas chromatography–mass spectrometry. Extraction conditions were optimized and 40 °C, 10 min, 250 rpm and 0.3 g NaCl for a 1 mL sample were the optimal conditions. This method showed good analytical performance in terms of sensitivity with limits of detection in serum (1 mL) of 0.03 µg/L for MTBE and 0.05 µg/L for TBA, accuracy (mean recovery values) from 75.8% to 85.8%, precision (relative standard deviations) <10% and sample stability (biodegradation) <10% after 28 days. A verification experiment proved the reproducibility and stability of this method as well. Finally the method was used to detect 212 specimens, and the internal dose levels for MTBE in human serum were presented in China. Copyright © 2015 John Wiley & Sons, Ltd.
A Resource Pathway to Action Against Discrimination: How Burnout and Work–Family Balance Form Obstacles to Action
Authors: Stroebe Katherine , Missler Marjolein
Published: March 2015

Why is it difficult for targets to act out against individual experiences of discrimination? Whereas prior research focuses on normative concerns or failure to perceive discrimination as determinants of (lack of) action, we hypothesize that perceiving frequent discrimination at work undermines the potential to act out against discrimination because it depletes one's resources. We study a sample that is underrepresented in research on discrimination, yet forms a large percentage of the working population: parents experiencing disadvantage in a working context. We measured self‐reported disadvantage because of parenthood, action against disadvantage, levels of burnout and work‐home self‐efficacy. Results reveal that perceptions of discrimination are related to lower levels of action. Importantly, lack of resources could explain this effect: we found simultaneous (and separate) mediation of the exhaustion (but not distancing) burnout subscale as well as separate mediation of work–home self‐efficacy. The implications of these results and the importance of studying potential resources in relation to action against discrimination are discussed. Copyright © 2015 John Wiley & Sons, Ltd.
Rational Design to Improve Protein Thermostability: Recent Advances and Prospects
Authors: Yang Haiquan , Liu Long , Li Jianghua , Chen Jian , Du Guocheng
Published: March 2015

Research on proteins is in rapid development, but the use of wild‐type proteins under industrial conditions has limitations, low thermostability in particular. Thermal stability includes three types: thermodynamic, kinetic, and process stability. Several factors (e.g., hydrophobic interactions and hydrogen bonds) affect the thermostability of proteins. The use of rational design to improve protein thermal stability is a hot topic in the field of computational biology and protein engineering. Several methods have been applied successfully to improve the thermal stability of protein, including introducing the number of disulfide bonds, optimizing protein surface charge, homologous comparison, and optimizing the free energy of unfolding. This review summarizes recent advances in our understanding of the factors influencing protein thermostability, highlights its effective improvement strategies, and discusses future prospects in this field.
Acid‐catalyzed Oxidation of Levulinate Derivatives to Succinates under Mild Conditions
Authors: Wang Yuran , Vogelgsang Ferdinand , Román‐Leshkov Yuriy
Published: March 2015

Levulinate derivatives are an attractive platform for the production of renewable chemicals. Here we report on the oxidation of methyl levulinate into dimethyl succinate with peroxides under mild conditions using Brønsted and Lewis acid catalysts. Selectivities to succinate and acetate derivatives of approximately 60 and 40 %, respectively, were obtained with strong Brønsted acids in methanol. Although the molecular structure (i.e., carbon‐chain length and branching around the CO group) and the oxidant type affect the product distribution, solvent choice has the strongest impact on changing the location of oxygen insertion into the carbon backbone. Specifically, switching the solvent from methanol to heptane resulted in a decrease in the succinate/acetate ratio from 1.6 to 0.3. In contrast to Brønsted acids, we demonstrate that the nature of the metal cation is responsible for changing the reaction selectivity of water‐tolerant Lewis acidic triflate salts.
Dendrimer‐Encapsulated Palladium Nanoparticles for Continuous‐Flow Suzuki–Miyaura Cross‐Coupling Reactions
Authors: Ricciardi Roberto , Huskens Jurriaan , Holtkamp Michael , Karst Uwe , Verboom Willem
Published: March 2015

The front cover artwork for Issue 06/2015 is provided by the Molecular Nanofabrication group at the University of Twente and the Institute of Inorganic and Analytical Chemistry at the University of Münster. The image shows the encapsulation of stable Pd nanoparticles (NPs) inside dendrimer templates that are anchored within continuous‐flow microreactors. The Pd NPs are very efficient catalysts for the Suzuki–Miyaura cross‐coupling reaction. See the Full Paper itself at http://dx.doi.org/10.1002/cctc.201500017.
Response Surface Optimization of Biodiesel Production via Catalytic Transesterification of Fatty Acids
Authors: Mir Maliheh , Ghoreishi Seyyed M.
Published: March 2015

Oil from Jatropha seeds was extracted by supercritical CO2. A catalytic transesterification reactor was employed for biodiesel production from extracted oil in which fatty acids like palmitic, stearic, oleic, and linoleic acid were converted to fatty acid methyl esters (FAMEs) with sodium methoxide as the catalyst. Gas chromatography‐flame ionization detector (GC‐FID) analysis identified and quantitatively determined the amount of FAMEs. Response surface methodology (RSM) was applied to find the optimal operating conditions in order to maximize the biodiesel yield. Under the RSM‐predicted optimum conditions, the maximum yields of four individual FAMEs and their combination as biodiesel were determined. The RSM model demonstrated that the linear and square terms of four variables and the interaction of flow rate and dynamic time significantly influence the biodiesel yield.
Oxidized Carbon Nitrides: Water‐Dispersible, Atomically Thin Carbon Nitride‐Based Nanodots and Their Performances as Bioimaging Probes
Authors: Oh Junghoon , Yoo Ran Ji , Kim Seung Yeon , Lee Yong Jin , Kim Dong Wook , Park Sungjin
Published: March 2015

Three‐dimensional (3D) carbon nitride (C3N4)‐based materials show excellent performance in a wide range of applications because of their suitable band structures. To realize the great promise of two‐dimensional (2D) allotropes of various 3D materials, it is highly important to develop routes for the production of 2D C3N4 materials, which are one‐atom thick, in order to understand their intrinsic properties and identify their possible applications. In this work, water‐dispersible, atomically thin, and small carbon nitride nanodots were produced using the chemical oxidation of graphitic C3N4. Various analyses, including X‐ray diffraction, X‐ray photoelectron, Fourier‐transform infrared spectroscopy, and combustion‐based elemental analysis, and thermogravimetric analysis, confirmed the production of 3D oxidized C3N4 materials. The 2D C3N4 nanodots were successfully exfoliated as individual single layers; their lateral dimension was several tens of nanometers. They showed strong photoluminescence in the visible region as well as excellent performances as cell‐imaging probes in an in vitro study using confocal fluorescence microscopy.
Pulse Radiolysis and Ultra‐High‐Performance Liquid Chromatography/High‐Resolution Mass Spectrometry Studies on the Reactions of the Carbonate Radical with Vitamin B12 Derivatives
Authors: Dassanayake Rohan S. , Shelley Jacob T. , Cabelli Diane E. , Brasch Nicola E.
Published: March 2015

The reactions of the carbonate radical anion (CO3.−) with vitamin B12 derivatives were studied by pulse radiolysis. The carbonate radical anion directly oxidizes the metal center of cob(II)alamin quantitively to give hydroxycobalamin, with a bimolecular rate constant of 2.0×109 M−1 s−1. The reaction of CO3.− with hydroxycobalamin proceeds in two steps. The second‐order rate constant for the first reaction is 4.3×108 M−1 s−1. The rate of the second reaction is independent of the hydroxycobalamin concentration and is approximately 3.0×103 s−1. Evidence for formation of corrinoid complexes differing from cobalamin by the abstraction of two or four hydrogen atoms from the corrin macrocycle and lactone ring formation has been obtained by ultra‐high‐performance liquid chromatography/high‐resolution mass spectrometry (UHPLC/HRMS). A mechanism is proposed in which abstraction of a hydrogen atom by CO3.− from a carbon atom not involved in the π conjugation system of the corrin occurs in the first step, resulting in formation of a CoIII C‐centered radical that undergoes rapid intramolecular electron transfer to form the corresponding CoII carbocation complex for about 50 % of these complexes. Subsequent competing pathways lead to formation of corrinoid complexes with two fewer hydrogen atoms and lactone derivatives of B12. Our results demonstrate the potential of UHPLC combined with HRMS in the separation and identification of tetrapyrrole macrocycles with minor modifications from their parent molecule.
Synthesis, Electronic Properties and WOLED Devices of Planar Phosphorus‐Containing Polycyclic Aromatic Hydrocarbons
Authors: Riobé François , Szűcs Rózsa , Bouit Pierre‐Antoine , Tondelier Denis , Geffroy Bernard , Aparicio Fátima , Buendía Julia , Sánchez Luis , Réau Régis , Nyulászi László , Hissler Muriel
Published: March 2015

We describe the synthesis and the physical properties of polyaromatic hydrocarbons (PAHs) containing a phosphorus atom at the edge. In particular, the impact of the successive addition of aromatic rings on the electronic properties was investigated by experimental (UV/Vis absorption, fluorescence, cyclic voltammetry) and theoretical studies (DFT). The physical properties recorded in solution and in the solid state showed that the P‐containing PAHs exhibit properties expected for an emitter in white organic light‐emitting diodes (WOLEDs).
Highly Active, Chemo‐ and Regioselective YbII and SmII Catalysts for the Hydrophosphination of Styrene with Phenylphosphine
Authors: Basalov Ivan V. , Dorcet Vincent , Fukin Georgy K. , Carpentier Jean‐François , Sarazin Yann , Trifonov Alexander A.
Published: March 2015

Stable heteroleptic amido YbII and SmII complexes bearing aminoether–phenolate ligands and devoid of coordinated solvent have been structurally characterized. They afford highly active, chemoselective and, in the case of monoadditions, 100 % anti‐Markovnikov regiospecific catalysts (down to 0.04 mol % loading) for the hydrophosphination of styrene with PhPH2 under mild conditions.
Intermolecular Asymmetric Carboesterification of Alkenes by Using Chiral Amine Auxiliaries under O2: Synthesis of Enantioenriched α‐Methylene‐γ‐Lactones through Chloropalladation of Alkynes
Authors: Zhang Zhenming , Wu Wanqing , Liao Jianhua , Li Jianxiao , Jiang Huanfeng
Published: March 2015

Herein, the first example of chloropalladation‐initiated asymmetric intermolecular carboesterification of alkenes with alkynes by using chiral amine auxiliaries is reported. The use of (1S,2S)‐N1,N1‐dimethylcyclohexane‐1,2‐diamine auxiliaries is essential for providing α‐methylene‐γ‐lactones products in moderate to high yields and excellent enantioselectivities at room temperature. Moreover, the chiral amine auxiliaries can be readily removed by hydrolysis during the reaction process to keep the absolute configuration. This oxygen‐ and water‐promoted asymmetric reaction opens a new window to study asymmetric processes in halopalladation reactions.
Diastereoselectively Switchable Asymmetric Haloaminocyclization for the Synthesis of Cyclic Sulfamates
Authors: Cai Yunfei , Zhou Pengfei , Liu Xiaohua , Zhao Jiannan , Lin Lili , Feng Xiaoming
Published: March 2015

An asymmetric synthesis of cyclic sulfamates by catalytic haloaminocyclization of primary sulfamate ester derivatives is described. The remarkable reversal of diastereoselectivity was found to be dependent on the halogen source and the chiral catalyst. By using privileged complexes of N,N′‐dioxides with Sc(OTf)3 or Lu(OTf)3 as the catalyst, a variety of enantioenriched syn‐ and anti‐cyclic sulfamates or related trans‐aziridines could be obtained in 92–99 % ee and up to 97 % yield.
A Photoinduced Cyclization Cascade—Total Synthesis of (−)‐Leuconoxine
Authors: Pfaffenbach Magnus , Gaich Tanja
Published: March 2015

A protecting‐group‐free and enantioselective total synthesis of the monoterpenoid indole alkaloid (−)‐leuconoxine was accomplished. The key step comprises a novel photoinduced domino macrocyclization/transannular cyclization involving the Witkop cyclization, for which additional mechanistic evidence is provided. This process furnishes a diaza[5.5.6.6]fenestrane skeleton, which is a hitherto unprecedented structure element.
Suppression of Problematic Compound Oligomerization by Cosolubilization of Nondetergent Sulfobetaines
Authors: Mizukoshi Yumiko , Takeuchi Koh , Arutaki Misa , Takizawa Takeshi , Hanzawa Hiroyuki , Takahashi Hideo , Shimada Ichio
Published: March 2015

Numerous small organic compounds exist in equilibrium among monomers, soluble oligomers, and insoluble aggregates in aqueous solution. Compound aggregation is a major reason for false positives in drug screening, and even soluble oligomers can interfere with structural and biochemical analyses. However, an efficient way to manage the equilibrium of aggregation‐prone compounds, especially those involved with soluble oligomers, has not been established. In this study, solution NMR spectroscopy was used as a suitable technique to detect compound oligomers in equilibrium, and it was demonstrated that cosolubilization of nondetergent sulfobetaines (NDSBs) can largely suppress compound oligomerization and aggregation by shifting the equilibrium toward the monomers. The rotational correlation time was obtained from the ratio of the selective and nonselective longitudinal NMR relaxation times, which directly and quantitatively reflected the apparent sizes of the compounds in the equilibrium. The rotational correlation time of the aggregation‐prone compound SKF86002 (1 mM) was substantially reduced from 0.31 to 0.23 ns by cosolubilization of 100 mM NDSB195. NDSB cosolubilization allowed us to perform successful structural and biochemical experiments with substantially fewer artifacts, which represents a strategy to directly resolve the problematic oligomerization and aggregation of compounds.
Universal Efficiency Improvement in Organic Solar Cells Based on a Poly(3‐hexylthiophene) Donor and an Indene‐C60 Bisadduct Acceptor with Additional Donor Nanowires
Authors: Joe Sung‐yoon , Yim Jong Hyuk , Ryu Shin Young , Ha Na Young , Ahn Yeong Hwan , Park Ji‐Yong , Lee Soonil
Published: March 2015

With poly(3‐hexylthiophene) (P3HT) nanowire (NW) inclusion in active layers (ALs), organic solar cells (OSCs) based on P3HT donor and indene‐C60 bisadduct (ICBA) acceptor showed power conversion efficiency (PCE) improvements for both bulk heterojunction (BHJ)‐ and bilayer (BL)‐structure AL devices. The PCE increase was approximately 14 % for both types of P3HT:ICBA OSCs. However, improvements in short‐circuit current density (Jsc) were about 4.4 and 6.4 % for BHJ‐ and BL‐type AL devices, respectively. A systematic study showed that the addition of P3HT NWs did not result in enhanced internal quantum efficiencies for either type of device. However, the difference in light‐harvesting efficiency was important in accounting for Jsc variations. Interestingly, there was no correlation between Jsc and PCE variations, whereas the open‐circuit voltage (Voc) and fill factor (FF) showed correlations with the PCE. The variation in FF is discussed in terms of Voc and equivalent‐circuit parameters based on a nonideal diode model.
Microscopic models for welfare measures addressing a reduction of economic inequality
Authors: Bertotti Maria Letizia , Modanese Giovanni
Published: March 2015

We formulate a flexible micro‐to‐macro kinetic model which is able to explain the emergence of income profiles out of a whole of individual economic interactions. The model is expressed by a system of several nonlinear differential equations which involve parameters defined by probabilities. Society is described as an ensemble of individuals divided into income classes; the individuals exchange money through binary and ternary interactions, leaving the total wealth unchanged. The ternary interactions represent taxation and redistribution effects. Dynamics is investigated through computational simulations, the focus being on the effects that different fiscal policies and differently weighted welfare policies have on the long‐run income distributions. The model provides a tool which may contribute to the identification of the most effective actions toward a reduction of economic inequality. We find for instance that, under certain hypotheses, the Gini index is more affected by a policy of reduction of the welfare and subsidies for the rich classes than by an increase of the upper tax rate. Such a policy also has the effect of slightly increasing the total tax revenue. © 2015 Wiley Periodicals, Inc. Complexity 21: 89–98, 2016
Boosting Properties of 3D Binder‐Free Manganese Oxide Anodes by Preformation of a Solid Electrolyte Interphase
Authors: Zhou Haitao , Wang Xuehang , Sheridan Edel , Chen De
Published: March 2015

Huge irreversible capacity loss prevents the successful use of metal oxide anodes in Li‐ion full cells. Here, we focus on the critical prelithiation step and demonstrate the challenge of electrolyte decomposition on a pristine anode in a full cell. Both an electrochemical activation process (54 h) with Li metal and a new electrolytic process (75 min) without Li metal were used to preform complete solid electrolyte interphase (SEI) layers on 3 D binder‐free MnOy‐based anodes. The preformed SEI layers mitigated the electrolyte decomposition effectively and widened the working voltage for the MnOy/LiMn2O4 full cell, which resulted in a big boost of the specific energy to 300 and 200 W h kgcathode−1, largely improved cycling stability, and much higher specific power (4200 W h kgtotal−1) compared to conventional Li‐ion batteries. Detailed characterization, such as cyclic voltammetry, scanning transmission electron microscopy, and FTIR spectroscopy, gives mechanistic insight into SEI preformation. This work provides guidance for the design of anode SEI layers and enables the application of oxides for Li‐ion battery full cells.
Can the Canadian drought code predict low soil moisture anomalies in the mineral soil? An analysis of 15 years of soil moisture data from three forest ecosystems in Eastern Canada
Authors: D'Orangeville Loïc , Houle Daniel , Duchesne Louis , Côté Benoît
Published: March 2015

The Canadian Drought Code (CDC) is an empirical soil‐drying model adapted to high‐latitude forests and commonly used by Canadian fire managers and researchers to predict the water content of the organic soil layer. Better knowledge of the capacity of the CDC to predict the effect of droughts on the water content of the mineral soil could improve our capacity to predict the future response of Canadian boreal forests to future changes in drought frequency and intensity.

We tested the capacity of the CDC to predict mineral soil water content (SWC) and droughts against long‐term (14–16 years) daily mineral SWC data from time domain reflectometry probes in multiple stations within three forest ecosystems of Eastern Canada respectively dominated by sugar maple, balsam fir and black spruce. Droughts were defined as SWC values lower than one standard deviation from their historical mean. The drought intensity and frequency of each growing season were computed as the sum of daily SWC departures from normal and the sum of days of drought, respectively.

Our results show that the CDC is a reliable predictor of mineral SWC (r = 0.6–0.8), drought frequency (r = 0.5–0.9) and intensity (r = 0.7–0.9) for high‐latitude forest ecosystems of Eastern Canada. Lower correlations were due to the poor accuracy of the model at predicting mild droughts at the sugar maple stand due to the SWC values close to the drought threshold. We detected a higher susceptibility to droughts at the black spruce stand due to a 1‐month‐earlier occurrence of severe droughts. Copyright © 2015 John Wiley & Sons, Ltd.
Diastereoselective Synthesis of Indolindiones by Formal [5+1] Double Michael Cycloaddition to 4‐Cinnamoylpyrrolediones
Authors: Silaichev Pavel S. , Filimonov Valeriy O. , Slepukhin Pavel A. , Rubin Michael , Maslivets Andrey N.
Published: March 2015

An efficient [5+1] double Michael cycloaddition of enolates to 4‐cinnamoylpyrrole‐2,3‐diones was investigated; the reaction allows for the highly diastereoselective assembly of indoline scaffolds with up to three contiguous stereogenic centers.
Standard error estimation for mixed flood distributions with historic maxima
Authors: Grego John M. , Yates Philip A. , Mai Kaiwen
Published: March 2015

Flood frequency data from multiple sources can be modeled using finite mixture models of stationary distributions. Historic flood data can be incorporated into this framework using censored data methods. Most estimation methods treat historical flood records as typical realizations from the underlying distribution, although they can actually represent extrema. A review of these methods in a finite mixture framework and introduction of an approach that treats historical maxima as order statistics are presented as adaptations of an expectation conditional maximization algorithm to derive estimates for the finite mixture model. When information matrices are difficult to computse, Meilijson's (1989) score‐based approximation is used instead. The total derivative method is used to compute standard errors for low‐frequency quantiles for both traditional censored data methods and the new approach. The method is demonstrated on annual peak flow data using mixtures of lognormal and Gumbel distributions. Copyright © 2015 John Wiley & Sons, Ltd.
Effect of laying sequence on egg mercury in captive zebra finches: An interpretation considering individual variation
Authors: Ou Langbo , Varian-Ramos Claire W. , Cristol Daniel A.
Published: March 2015

Bird eggs are used widely as noninvasive bioindicators for environmental mercury availability. Previous studies, however, have found varying relationships between laying sequence and egg mercury concentrations. Some studies have reported that the mercury concentration was higher in first-laid eggs or declined across the laying sequence, whereas in other studies mercury concentration was not related to egg order. Approximately 300 eggs (61 clutches) were collected from captive zebra finches dosed throughout their reproductive lives with methylmercury (0.3 μg/g, 0.6 μg/g, 1.2 μg/g, or 2.4 μg/g wet wt in diet); the total mercury concentration (mean ± standard deviation [SD] dry wt basis) of their eggs was 7.03 ± 1.38 μg/g, 14.15 ± 2.52 μg/g, 26.85 ± 5.85 μg/g, and 49.76 ± 10.37 μg/g, respectively (equivalent to fresh wt egg mercury concentrations of 1.24 μg/g, 2.50 μg/g, 4.74 μg/g, and 8.79 μg/g). The authors observed a significant decrease in the mercury concentration of successive eggs when compared with the first egg and notable variation between clutches within treatments. The mercury level of individual females within and among treatments did not alter this relationship. Based on the results, sampling of a single egg in each clutch from any position in the laying sequence is sufficient for purposes of population risk assessment, but it is not recommended as a proxy for individual female exposure or as an estimate of average mercury level within the clutch. Environ Toxicol Chem 2015;34:1787–1792. © 2015 SETAC
Incorporating variability in point estimates in risk assessment: Bridging the gap between LC50 and population endpoints
Authors: Stark John D. , Vargas Roger I. , Banks John E.
Published: March 2015

Historically, point estimates such as the median lethal concentration (LC50) have been instrumental in assessing risks associated with toxicants to rare or economically important species. In recent years, growing awareness of the shortcomings of this approach has led to an increased focus on analyses using population endpoints. However, risk assessment of pesticides still relies heavily on large amounts of LC50 data amassed over decades in the laboratory. Despite the fact that these data are generally well replicated, little or no attention has been given to the sometime high levels of variability associated with the generation of point estimates. This is especially important in agroecosystems where arthropod predator–prey interactions are often disrupted by the use of pesticides. Using laboratory derived data of 4 economically important species (2 fruit fly pest species and 2 braconid parasitoid species) and matrix based population models, the authors demonstrate in the present study a method for bridging traditional point estimate risk assessments with population outcomes. The results illustrate that even closely related species can show strikingly divergent responses to the same exposures to pesticides. Furthermore, the authors show that using different values within the 95% confidence intervals of LC50 values can result in very different population outcomes, ranging from quick recovery to extinction for both pest and parasitoid species. The authors discuss the implications of these results and emphasize the need to incorporate variability and uncertainty in point estimates for use in risk assessment. Environ Toxicol Chem 2015;34:1683–1688. © 2015 SETAC
Exploration of Daphnia behavioral effect profiles induced by a broad range of toxicants with different modes of action
Authors: Chevalier Julie , Harscoët Elodie , Keller Merlin , Pandard Pascal , Cachot Jérôme , Grote Matthias
Published: March 2015

Behavior is increasingly reported as a sensitive and early indicator of toxicant stress in aquatic organisms. However, the systematic understanding of behavioral effects and comparisons between effect profiles is hampered because the available studies are limited to few chemicals and differ in the exposure conditions and effect parameters examined. The aims of the present study were 1) to explore behavioral responses of Daphnia magna exposed to different toxicants, 2) to compare behavioral effect profiles with regard to chemical modes of action, and 3) to determine the sensitivity and response time of behavioral parameters in a new multi-cell exposure system named Multi-DaphTrack compared with currently utilized tests. Twelve compounds covering different modes of toxic action were selected to sample a wide range of potential effect profiles. Acute standard immobilization tests and 48 h of behavioral tracking were performed in the customized Multi-DaphTrack system and a single-cell commercialized biological early warning system. Contrasting behavioral profiles were observed for average speed (i.e., intensity, time of effect onset, effect duration), but no distinct behavioral profiles could be drawn from the chemical mode of action. Most compounds tested in the Multi-DaphTrack system induced an early and significant average speed increase at concentrations near or below the 10% effective concentration (48 h) of the acute immobilization test, demonstrating that the Multi-DaphTrack system is fast and sensitive. To conclude, behavior endpoints could be used as an alternative or complement to the current acute standard test or chemical analysis for the predictive evaluation of ecotoxic effects of effluents or water bodies. Environ Toxicol Chem 2015;34:1760–1769. © 2015 SETAC
Task‐sensitive reconfiguration of corticocortical 6–20 Hz oscillatory coherence in naturalistic human performance
Authors: Saarinen Timo , Jalava Antti , Kujala Jan , Stevenson Claire , Salmelin Riitta
Published: March 2015

Electrophysiological oscillatory coherence between brain regions has been proposed to facilitate functional long‐range connectivity within neurocognitive networks. This notion is supported by intracortical recordings of coherence in singled‐out corticocortical connections in the primate cortex. However, the manner in which this operational principle manifests in the task‐sensitive connectivity that supports human naturalistic performance remains undercharacterized. Here, we demonstrate task‐sensitive reconfiguration of global patterns of coherent connectivity in association with a set of easier and more demanding naturalistic tasks, ranging from picture comparison to speech comprehension and object manipulation. Based on whole‐cortex neuromagnetic recording in healthy behaving individuals, the task‐sensitive component of long‐range corticocortical coherence was mapped at spectrally narrow‐band oscillatory frequencies between 6 and 20 Hz (theta to alpha and low‐beta bands). This data‐driven cortical mapping unveiled markedly distinct and topologically task‐relevant spatiospectral connectivity patterns for the different tasks. The results demonstrate semistable oscillatory states relevant for neurocognitive processing. The present findings decisively link human behavior to corticocortical coherence at oscillatory frequencies that are widely thought to convey long‐range, feedback‐type neural interaction in cortical functional networks. Hum Brain Mapp 36:2455–2469, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc..
Do Health Reforms to Improve Quality Have Long‐Term Effects? Results of a Follow‐Up on a Randomized Policy Experiment in the Philippines
Authors: Quimbo Stella , Wagner Natascha , Florentino Jhiedon , Solon Orville , Peabody John
Published: March 2015

We tracked doctors who had previously participated in a randomized policy experiment in the Philippines. The original experiment involved 30 district hospitals divided equally into one control site and two intervention sites that increased insurance payments (full insurance support for children under 5 years old) or made bonus payments to hospital staff. During the 3 years of the intervention, quality—as measured by clinical performance and value vignettes—improved and was sustained in both intervention sites compared with controls. Five years after the interventions were discontinued, we remeasured the quality of care of the doctors. We found that the intervention sites continued to have significantly higher quality compared with the control sites. The previously documented quality improvement in intervention sites appears to be sustained; moreover, it was subject to a very low (less than 1% per year) rate of decay in quality scores. Copyright © 2015 John Wiley & Sons, Ltd.
Financing Long‐Term Care: Ex Ante, Ex Post or Both?
Authors: COSTA‐FONT Joan , Courbage Christophe , Swartz Katherine
Published: March 2015

This paper attempts to examine the heterogeneity in the public financing of long‐term care (LTC) and the wide‐ranging instruments in place to finance LTC services. We distinguish and classify the institutional responses to the need for LTC financing as ex ante (occurring prior to when the need arises, such as insurance) and ex post (occurring after the need arises, such as public sector and family financing). Then, we examine country‐specific data to ascertain whether the two types of financing are complements or substitutes. Finally, we examine exploratory cross‐national data on public expenditure determinants, specifically economic, demographic and social determinants. We show that although both ex ante and ex post mechanisms exist in all countries with advanced industrial economies and despite the fact that instruments are different across countries, ex ante and ex post instruments are largely substitutes for each other. Expenditure estimates to date indicate that the public financing of LTC is highly sensitive to a country's income, ageing of the population and the availability of informal caregiving. Copyright © 2015 John Wiley & Sons, Ltd.
Age‐related decrease in theta and gamma coherence across dorsal ca1 pyramidale and radiatum layers
Authors: Jacobson Tara K. , Schmidt Brandy , Hinman James R. , Escabí Monty A. , Markus Etan J.
Published: March 2015

In both humans and rodents, aging is linked to impairments in hippocampus dependent learning. Given such deficits, one would expect corresponding changes in hippocampal local field potentials, which represent the integration of multiple inputs onto a given dendritic field within the hippocampus. The current experiment examined coherence of theta and gamma in young and aged rats at sub‐millimeter and millimeter distant locations both within and across layers in CA1 of the dorsal hippocampus. The degree to which different dendritic layers show coherent oscillations indicates the uniformity of the inputs and local circuitry, and may form an important element for processing information. Aged rats had lower coherence in all frequency ranges; this was most marked within a layer as the distance between electrodes increased. Notably, unlike younger rats, in the aged rats coherence was not affected by running on the maze. Furthermore, despite the previously reported effects of cholinergic activation on theta frequency and power, there was no effect of the cholinomimetic physostigmine on coherence. These data indicate an age related fragmentation in hippocampal processing that may underlie some of the observed learning and memory deficits. © 2015 Wiley Periodicals, Inc.
Using airborne LiDAR to determine total sapwood area for estimating stand transpiration in plantations
Authors: Saito Takami , Yamamoto Kazukiyo , Komatsu Misako , Matsuda Hiroki , Yunohara Shuji , Komatsu Hikaru , Tateishi Makiko , Xiang Yang , Otsuki Kyoichi , Kumagai Tomo'omi
Published: March 2015

This study offers an unprecedented opportunity to estimate total sapwood area over an entire catchment (Ascat/Ag) using small‐footprint light detection and ranging technology with a minimal amount of labour in field. Forty‐two‐year‐old plantations of Japanese cypress (Hinoki; Chamaecyparis obtusa Sieb. et Zucc.) and Japanese cedar (Sugi; Cryptomeria japonica D. Don) vegetated the 2.98 ha experimental catchment. Field observations identified diameter at breast height (DBH) of all trees and produced the relationship between DBH and tree sapwood area (Astre). The sum of Astre generated actual values of Ascat/Ag. For light detection and ranging data analyses, local maximum filtering revealed height of tree apices (H) and tree number (N) with 9% omission errors. A novel process was developed to identify tree species by their apices based on height of the apices and canopy roughness. Four methods were tested. In Methods A–C, H was converted to Astre directly or via DBH, then, the sum of Astre created Ascat/Ag. H–Astre or H–DBH relationships were varied irrespective of labour‐intensive measurements, and Ascat/Ag was underestimated up to 85% of actual value because of the smaller N. On the other hand, in Method D, ready‐made stand density management diagrams (SDMDs) overestimated mean DBH. However, a product of overestimated mean Astre and the underestimated N was almost identical to the actual Ascat/Ag. The estimates were 84% and 95% of the true Ascat/Ag in Hinoki and Sugi, respectively, and the former will be more precise if the SDMD is suitable for the site as indicated through sensitivity analysis. Copyright © 2015 John Wiley & Sons, Ltd.
Ex vivo optical measurements of glucose diffusion kinetics in native and diabetic mouse skin
Authors: Tuchina Daria K. , Shi Rui , Bashkatov Alexey N. , Genina Elina A. , Zhu Dan , Luo Qingming , Tuchin Valery V.
Published: March 2015

The aim of this study was to estimate the glucose diffusion coefficients ex vivo in skin of mice with diabetes induced in vivo by alloxan in comparison to non‐diabetic mice. The temporal dependences of collimated transmittance of tissue samples immersed in glucose solutions were measured in the VIS‐NIR spectral range to quantify the glucose diffusion/permeability coefficients and optical clearing efficiency of mouse skin. The average thickness of intact healthy and diabetic skin was 0.023 ± 0.006 cm and 0.019 ± 0.005 cm, respectively. Considerable differences in optical and kinetic properties of diabetic and non‐diabetic skin were found: clearing efficiency was 1.5‐fold better and glucose diffusivity was 2‐fold slower for diabetic skin.

Experimental Setup for measuring collimated transmittance spectra of mouse skin samples.

magnified image

Experimental Setup for measuring collimated transmittance spectra of mouse skin samples.
An Initial Investigation of the Relationship Between Insomnia and Hoarding
Authors: Raines Amanda M. , Portero Amberly K. , Unruh Amanda S. , Short Nicole A. , Schmidt Norman B.
Published: March 2015

Objective

Insomnia has been shown to have profound negative consequences on multiple aspects of daily functioning. Despite increased interest in the association between insomnia and psychopathology, no research has examined the relationships between insomnia and hoarding. The aim of the current investigation was to examine the associations between insomnia and hoarding severity.

Methods

Participants consisted of patients with hoarding disorder (n = 24).

Results

Results revealed that insomnia was a significant predictor of increased hoarding severity. In addition, when examining the relationships among insomnia and specific hoarding symptoms, sleep difficulties were associated with increased acquiring and difficulty discarding behaviors.

Conclusions

These findings add to a growing body of literature on insomnia and various forms of psychopathology, as well as research on symptoms related to hoarding. Reducing insomnia symptoms among hoarders may help to reduce hoarding‐related behaviors and increase treatment efficacy.
ACCESS TO NEW INFORMATION AND COMMUNICATION TECHNOLOGIES AMONG HOMELESS PEOPLE IN MADRID (SPAIN)
Authors: Vázquez José Juan , Panadero Sonia , Martín Rosa , del Val Diaz‐Pescador María
Published: March 2015

The article analyzes access to various information and communication technologies (ICTs; mobile phone, computer, Internet, e‐mail, and social network sites) among a representative sample of homeless people in Madrid. The information was collected using a structured interview. The results show that new ICTs are used to some extent among homeless people in Madrid, although at much lower percentages than the general population in Spain. We observed a relatively widespread use of mobile phones, a medium‐low level use of the Internet, computer, and e‐mail, and hardly any use of social networks, with significant differences according to the interviewees' age, level of education, and Spanish or foreign nationality. The digital divide has an especially negative effect on elderly homeless people, those with lower levels of education, and those of Spanish origin.
IDENTIFICATION AMONG FIRST‐GENERATION CITIZEN STUDENTS AND FIRST‐GENERATION COLLEGE STUDENTS: AN EXPLORATION OF SCHOOL SENSE OF COMMUNITY
Authors: Williams Shannon M. , Ferrari Joseph R.
Published: March 2015

The current study explored the relationships within a higher education institution between school sense of community among first‐generation U.S. citizen students and first‐generation college students compared to students of non‐first generation studentship and citizenship (N = 3,025; M age = 27.21), and of varied racial backgrounds. Students at a large, urban, and faith‐based university completed a measure of belongingness on campus. In terms of generational status, results found a significant interaction such that students who were both first‐generation U.S. citizen students and first‐generation college students reported the highest school sense of community. However, the combined first‐generation U.S. citizen students and non‐first‐generation college student group reported the lowest scores. Despite these significant findings, sense of community scores were very similar with few differences between groups, which is further discussed in the discussion and limitation sections. Significant racial differences were not found. Implications for community psychology and higher education policy are discussed.