bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient Photoinduced Energy and Electron Transfer in ZnII–Porphyrin/Fullerene Dyads with Interchromophoric Distances up to 2.6 nm and No Wire‐like Connectivity
Authors: Mohanraj John , Barbieri Andrea , Armaroli Nicola , Vizuete María , Langa Fernando , Delavaux‐Nicot Béatrice , Vartanian Maida , Iehl Julien , Hahn Uwe , Nierengarten Jean‐François 
Published: July 2017

AbstractThe dyads 1–3 made of an alkynylated ZnII–porphyrin and a bis‐methanofullerene derivative connected through a copper‐catalyzed azide–alkyne cycloaddition have been synthesized. The porphyrin and fullerene chromophores are separated through a bridge made of a bismethanofullerene tether linked to different spacers conjugated to the porphyrin moiety [i.e., m‐phenylene (1), p‐phenylene (2), di‐p‐phenylene‐ethynylene (3)]. Compounds 1–3 exhibit relatively rigid structures with an interchromophoric separation of 1.7, 2.0, and 2.6 nm, respectively, and no face‐to‐face or direct through‐bond conjugation. The photophysical properties of compounds 1–3 have been investigated in toluene and benzonitrile with steady‐state and time‐resolved techniques as well as model calculations on the Förster energy transfer. Excited‐state interchromophoric electronic interactions are observed with a distinct solvent and distance dependence. The latter effect is evidenced in benzonitrile, where compounds 1 and 2 exhibit a photoinduced electron transfer in the Marcus‐inverted region, with charge‐separated (CS) states living for 0.44 and 0.59 μs, respectively, whereas compound 3 only undergoes energy transfer, as in apolar toluene. The quantum yield of the charge separation (φCS) of compounds 1 and 2 in benzonitrile is ≥0.75. It is therefore demonstrated that photoinduced energy and electron transfers in porphyrin–fullerene systems with long interchromophoric distances may efficiently occur also when the bridge does not provide a wire‐like conjugation and proceed through the triplet states of the chromophoric moieties.
Alkyl Esterification of Vinylarenes Enabled by Visible‐Light‐Induced Decarboxylation
Authors: Ge Liang , Li Yajun , Jian Wujun , Bao Hongli 
Published: July 2017

AbstractA decarboxylative alkyl esterification of vinylarenes induced by visible light is described. A variety of alkyl diacyl peroxides synthesized from readily available aliphatic carboxylic acids are used as not only the oxygenation but also alkylation source. This simple and easy to handle reaction has a wide substrate scope, excellent yields, and works under mild reaction conditions. Carbon dioxide is the sole byproduct. An oxidative quenching process is proposed as the mechanism.
Efficient One‐Pot Multifunctionalization of Alkynes en Route to α‐Alkoxyketones, α‐Thioketones, and α‐Thio Thioketals by using an Umpolung Strategy
Authors: Xu Zhou , Zhai Rongliang , Liang Ting , Zhang Liming 
Published: July 2017

AbstractThe use of polarized synthons is a highly desirable strategy, as it generally enables unprecedented retrosynthetic disconnections for the synthesis of unique substances. Herein, a new approach for α‐oxygenated ketones, α‐thioketones and α‐thio thioketals via an intermolecular umpolung reaction between nucleophiles (alcohols/thioalcohols) and N‐alkenoxypyridinium salts, which were generated from the corresponding alkynes, has been developed for the first time. The reactions proceed with good substrate scope and excellent functional group tolerance in one‐pot manner. Applications of the products, α‐oxygenated ketones, to the synthesis of other valuable synthetic moieties has also been successfully achieved.
Predicting personality associations evoked by multicolored appearance of virtual agents: An exploratory study
Authors: Wu Zhiming , Lin Tao , Xu Hongyan , Tang Ningjiu 
Published: July 2017

AbstractDesigning agents' color appearance that can evoke desired color‐personality associations (CPAs) is still a challenge. To respond to the challenge, this study proposed a multicolor personality index (MCPI) model to predict the CPAs evoked by agents using the color‐personality indices for single colors together with the histogram of agents' image. Specifically, the color personality index for each bin of an agent's histogram was first calculated based on the color‐personality indices for single colors; then, the predicted values of CPAs were obtained by calculating the weighted average of color‐personality indices of all bins in the histogram. To improve the MCPI model, a simple color‐attention index model was proposed to evaluate the effects of color on attention and the effects were introduced into the MCPI model, that is, the multi‐color personality index based on color attention (MCPI‐CA) model. To validate the two models, an experiment was conducted to collect the CPAs of five traits (i.e., extraverted‐introverted, moody‐unemotional, agreeable‐disagreeable, organized‐disorganized, and wide interests‐narrow interests) evoked by the multi‐colored appearance of agents. The results showed that (a) observers in general perceived the CPAs evoked by color appearance in similar way; (b) for most agents, the CPAs evoked by multi‐colored appearance could be predicted well by the MCPI model; and (c) the MCPI‐CA model usually had better performance than the MCPI model due to the inclusion of the effects of color attributes on attention. In addition, the limitations of the proposed models and their implications for designers were also discussed.
Hyperpolarizing Water with Parahydrogen
Authors: Lehmkuhl Sören , Emondts Meike , Schubert Lukas , Spannring Peter , Klankermayer Jürgen , Blümich Bernhard , Schleker P. Philipp M. 
Published: July 2017

AbstractStudies of water‐based systems are of fundamental interest for nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) as water is the most abundant and important medium for global living. Hence, increasing the polarization of water and dissolved compounds is particularly attractive for biomedical applications such as investigations of intermolecular interactions and metabolite structures as well as for imaging purposes. In this work, we show a new approach based on para enriched hydrogen (p‐H2) that enables the hyperpolarization of bulk water if a suitable catalytic system is employed. The results indicate that the polarization is transferred by a new exchange mechanism.
Protonation‐State‐Driven Photophysics in Phenothiazinium Dyes: Intersystem Crossing and Singlet‐Oxygen Production
Authors: Rodriguez‐Serrano Angela , Daza Martha C. , Doerr Markus , Tatchen Jörg , Marian Christel M. 
Published: July 2017

AbstractThe impact of altering the solvent pH value on the photodynamic activity of thionine has been studied computationally by means of density functional theory and multi‐reference interaction methods. To this end, we have investigated the electronic structure of the ground and excited states of diprotonated (TH22+) and neutral imine (T) forms of thionine (TH+). It is well known experimentally that the T1 state of TH+ undergoes acid–base equilibrium reactions resulting in a pronounced pH effect for the efficiency of singlet‐oxygen (1O2) production. Our results show that the energy‐transfer reactions from the T1 state of TH22+ and T to 3O2 correspond to reversible equilibrium processes, whereas in TH+ this process is very exothermic in a vacuum (−0.66 eV) and in aqueous solution (−0.49 eV). These facts explain the experimental observation of a much smaller efficiency of 1O2 production for TH22+ than for TH+. Moreover, we found that the pH value significantly effected the intersystem crossing (ISC) kinetics impacting the concentration of triplet‐state species available for energy transfer. In very acidic aqueous solution (pH<2) where TH22+ is the prevailing species, the ISC proceeds with a rate constant of ≈108 s−1. In a basic medium where T is the dominant species, ISC decay occurs by means of a thermally activated channel (≈108 s−1) which competes with fluorescence (5.32×107 s−1). According to these results, maximum ISC efficiency is expected for intermediate acidic pH values (TH+, ≈109 s−1).
Energy‐efficient communications over multiple access relay channels
Authors: Moeen Taghavi Ehsan , Abed Hodtani Ghosheh 
Published: July 2017

SummaryRecently, due to the importance of green communications and power‐limited systems, energy efficiency in vehicular technologies has become a hot research topic. In this paper, we analyze energy‐efficient coding schemes in multiple access relay channels. First, the coding scheme in the multiple access relay channel is introduced. At the desired source rates, 3 optimal sets of resource allocation (the total power consumption, the relay power consumption, and the source power consumption) are given in the closed form. The analysis shows that the proposed energy‐efficient schemes achieve higher data rates and significantly outperform especially by reducing the relay energy consumption, which is useful for the shared relays. Moreover, the results allow a comprehensive description of the power consumption systems and give a detailed understanding of the desired message coding and the resource dedication for every desired sum rate.
New methods for enhancing fine acquisition in dual folding algorithm of long pseudo noise codes
Authors: Borna Maryam , Madani Mohammad Hossein 
Published: July 2017

SummaryLong code Direct Sequence Spread Spectrum is a good choice for applications where security and antispoofing ability of a spread spectrum connection is concerned. Due to long period of spreading code, acquisition is a challenge for these systems because a trade‐off between detection probability and acquisition time must be made. For confronting this challenge, various algorithms were proposed in the literature but almost all of them focus on expediting the coarse acquisition. In this paper, we consider the efficient dual folding algorithm for coarse acquisition level and propose 3 methods for enhancing the fine acquisition level leading to faster execution of overall acquisition algorithm. The methods are based on estimations from coarse acquisition level that are not used in conventional algorithms for fine acquisition, ie, zero padding. Theoretical expressions of 2 main comparison criteria in acquisition algorithms, ie, detection probability and mean acquisition time, are derived for conventional zero padding and each of the proposed method. Besides, a coarse estimate of resource consumption is provided by the number of floating point operations for each algorithm to make a useful comparison. Considering these 3 parameters, in comparison, the proposed methods surpass zero padding in 1, 2, or all of the 3 aspects. Simulation agrees well with analytical results.
The spitting image of plant defenses: Effects of plant secondary chemistry on the efficacy of caterpillar regurgitant as an anti‐predator defense
Authors: Desurmont Gaylord A. , Köhler Angela , Maag Daniel , Laplanche Diane , Xu Hao , Baumann Julien , Demairé Camille , Devenoges Delphine , Glavan Mara , Mann Leslie , Turlings Ted C. J. 
Published: July 2017

AbstractIn the arms race between plants, herbivores, and their natural enemies, specialized herbivores may use plant defenses for their own benefit, and variation in plant traits may affect the benefits that herbivores derive from these defenses. Pieris brassicae is a specialist herbivore of plants containing glucosinolates, a specific class of defensive secondary metabolites. Caterpillars of P. brassicae are known to actively spit on attacking natural enemies, including their main parasitoid, the braconid wasp Cotesia glomerata. Here, we tested the hypothesis that variation in the secondary metabolites of host plants affects the efficacy of caterpillar regurgitant as an anti‐predator defense. Using a total of 10 host plants with different glucosinolate profiles, we first studied natural regurgitation events of caterpillars on parasitoids. We then studied manual applications of water or regurgitant on parasitoids during parasitization events. Results from natural regurgitation events revealed that parasitoids spent more time grooming after attack when foraging on radish and nasturtium than on Brassica spp., and when the regurgitant came in contact with the wings rather than any other body part. Results from manual applications of regurgitant showed that all parameters of parasitoid behavior (initial attack duration, attack interruption, grooming time, and likelihood of a second attack) were more affected when regurgitant was applied rather than water. The proportion of parasitoids re‐attacking a caterpillar within 15 min was the lowest when regurgitant originated from radish‐fed caterpillars. However, we found no correlation between glucosinolate content and regurgitant effects, and parasitoid behavior was equally affected when regurgitant originated from a glucosinolate‐deficient Arabidopsis thaliana mutant line. In conclusion, host plant affects to a certain extent the efficacy of spit from P. brassicae caterpillars as a defense against parasitoids, but this is not due to glucosinolate content. The nature of the defensive compounds present in the spit remains to be determined, and the ecological relevance of this anti‐predator defense needs to be further evaluated in the field.
Developing a capillary electrophoresis based method for dynamically monitoring enzyme cleavage activity using quantum dots‐peptide assembly
Authors: Wang Jianhao , Fan Jie , Liu Li , Ding Shumin , Liu Xiaoqian , Wang Jianpeng , Gao Liqian , Chattopadhaya Souvik , Miao Peng , Xia Jiang , Qiu Lin , Jiang Pengju 
Published: July 2017

AbstractHerein, a novel assay has been developed for monitoring PreScission protease (His‐PSP) mediated enzyme cleavage of ATTO 590 labeled peptide substrate (ATTO‐LEV). This novel method is based on combining the use of capillary electrophoresis and fluorescence detection (CE‐FL) to dynamically monitor the enzyme cleavage activity. A multivalent peptide substrate was first constructed by immobilizing His‐tagged ATTO 590 labeled peptide substrate (ATTO‐LEVH6) onto the surface of CdSe/ZnS quantum dots (QDs). Once successfully immobilized, the novel multivalent peptide substrate resulted in the Förster resonance energy transfer (FRET) from QDs to ATTO 590. The ATTO‐LEVH6‐QD assembly was then incubated with His‐PSP to study the proteolytic cleavage of surface bound ATTO‐LEVH6 by CE‐FL. Our data suggests that PreScission‐mediated proteolytic cleavage is enzyme concentration‐ and incubation time‐dependent. By combining capillary electrophoresis, QDs and FRET, our study herein not only provides a new method for the detection and dynamically monitoring of PSP enzyme cleavage activity, but also can be extended to the detection of many other enzymes and proteases.
Quantitative analysis of flavonoids and phenolic acid in Coreopsis tinctoria Nutt. by capillary zone electrophoresis
Authors: Deng Yong , Lam Shing‐Chung , Zhao Jing , Li Shao‐Ping 
Published: July 2017

AbstractCapillary zone electrophoresis was developed for the simultaneous determination of five flavonoids and one phenolic acid, including taxifolin‐7‐O‐glucoside, flavanomarein, quercetagetin‐7‐O‐glucoside, okanin 4′‐O‐glucoside, okanin, and chlorogenic acid, in different parts and origins of Coreopsis tinctoria and its related species. Effects of acidity, running‐buffer concentration, and modifier concentration were investigated to determine the optimum conditions for analyte determination. Analysis was performed within 18 min by using 50 mM borax buffer containing 15% acetonitrile as a modifier (pH 9.0) at 25 kV and 25°C. Hyperoside was used as internal standard for quantification. The method was accurate, simple, and repeatable, and was successfully applied to the analysis in 13 samples with satisfactory assay results. Results showed that C. tinctoria obviously differed from the related flower tea materials, “Hangju” and “Gongju”. The parts (flowers, buds, seeds, stems, and leaves) of C. tinctoria also varied among one another. This study can serve as a foundation for the quality control and pharmacological evaluation of different parts of C. tinctoria and its related species.
Stability of polymersomes with focus on their use as nanoreactors
Authors: Poschenrieder Sarah Theresa , Schiebel Sina Katharina , Castiglione Kathrin 
Published: July 2017

AbstractThe increased membrane stability of polymersomes compared to their liposomal counterparts is one of their most important advantages. Due to this benefit, polymer vesicles are intended to be used not only as carrier systems for drug delivery purposes but also as nanoreactors for biotechnological applications. Within this work, the stability of polymersomes made of the triblock copolymer poly(2‐methyloxazoline)15‐poly(dimethylsiloxane)68‐poly(2‐methyloxazoline)15 (PMOXA15‐PDMS68‐PMOXA15) toward mechanical stress, typically prevailing in stirred‐tank reactors being the most often used reactor type in the biotechnological industry, was characterized. Dynamic light scattering and turbidity measurements showed that stirrer rotation causing a maximum local energy dissipation of up to 1.23 W/kg−1 did not result in any loss of vesicle quality or quantity. Nevertheless, most probably due to local membrane defects, 6.6% release of the previously encapsulated model dye calcein was recognized at 25°C within 48 h. Moreover, increased temperature, leading to decreased membrane viscosity and increased membrane fluidity, respectively, led to a higher molecule leakage. Besides, the stability of polymersomes in two‐phase systems was investigated. Although alkanes and ionic liquids were shown not to lead to complete vesicle damage, no efficient calcein retention was achieved in either case.
Analytical model for the out‐of‐plane response of vertically spanning unreinforced masonry walls
Authors: Godio Michele , Beyer Katrin 
Published: July 2017

SummaryAn analytical model describing the flexural response of vertically spanning out‐of‐plane loaded unreinforced masonry walls is presented in this paper. The model is based on the second‐order Euler‐Bernoulli beam theory and captures important characteristics of the out‐of‐plane response of masonry walls that have been observed in experimental tests and from numerical studies but for which an analytical solution was still lacking: the onset and the evolution of cracking, the peak strength of the out‐of‐plane loaded walls, and the softening of the response due to P−Δ effects. The model is validated against experimental results, and the comparison shows that the model captures both the prepeak and postpeak response of the walls. From the analytical model of the force‐displacement curve, a formula for the maximum out‐of‐plane strength of the walls is derived, which can be directly applied in engineering practice.
Smoking and subsequent risk of acute myeloid leukaemia: A pooled analysis of 9 cohort studies in Japan
Authors: Ugai Tomotaka , Matsuo Keitaro , Oze Isao , Ito Hidemi , Wakai Kenji , Wada Keiko , Nagata Chisato , Nakayama Tomio , Liu Rong , Kitamura Yuri , Tamakoshi Akiko , Tsuji Ichiro , Sugawara Yumi , Sawada Norie , Sadakane Atsuko , Tanaka Keitaro , Mizoue Tetsuya , Inoue Manami , Tsugane Shoichiro , Shimazu Taichi ,   for the Research Group for the Development and Evaluation of Cancer Prevention Strategies in Japan
Published: July 2017

AbstractSmoking has been identified as a significant risk factor for acute myeloid leukaemia (AML). However, epidemiological evidence for the effect of smoking on the risk of AML among Asians is scarce. Here, we investigated the impact of smoking habits on the risk of AML by conducting a pooled analysis of 9 population‐based prospective cohort studies in Japan. We analysed original data on smoking habits at baseline from 9 cohort studies. Hazard ratios (HRs) in the individual studies were calculated using a Cox proportional hazard model adjusted for potential confounders and combined using a random‐effects model. During 4 808 175 person‐years of follow‐up for a total of 344 676 participants (165 567 men and 179 109 women), 245 AML cases (139 men and 106 women) were identified. For both sexes combined, current smokers had a marginally significant increased risk of AML compared to never smokers (HR = 1.44, 95% confidence interval [CI], 0.97‐2.14). Ever smokers with more than 30 pack‐years had a statistically significant increased risk of AML compared to never smokers among both sexes combined (HR = 1.66, 95% CI, 1.06‐2.63). By sex, this significant association was observed only among men, with an HR of 1.69 (95% CI, 1.00‐2.87) for ever smokers with more than 30 pack‐years relative to never smokers. In conclusion, this study confirmed that cigarette smoking increases the risk of AML in Japanese. This study provides important evidence that smoking increases the risk of AML among Asians, which has already been shown in Western populations.
On Water and its Effect on the Performance of T1‐Shortening Contrast Agents
Authors: Payne Katherine M. , Wilds Jennifer M. , Carniato Fabio , Botta Mauro , Woods Mark 
Published: July 2017

AbstractThe performance of low molecular weight Gd3+ chelates as T1‐shortening contrast agents for MRI is limited by their rapid rate of molecular tumbling, which makes them very sensitive to factors that alter the rate of molecular reorientation. Unlike the interactions of these chelates with other solutes present in solution, which have been widely studied, the effect of the solvent water itself on tumbling seems to have been largely ignored. Water has long been known to adopt structures that vary from freely diffusing molecules on one extreme and a more “ice‐like” structure on the other. A variety of salts can be used to alter this “structure” of water. Relaxometric studies on inner and outersphere Gd3+ chelates were performed in the presence of both structure making and structure breaking salts. The addition of structure‐making salts to low molecular weight Gd3+ chelates was found to increase both the second‐ and outer‐sphere contributions to relaxivity. These results point to a slowing of molecular tumbling arising from an increase solvent structure and therefore microviscosity. The implication of these findings is that the performance of low molecular weight Gd3+ contrast agents is not, as generally assumed, constant in the absence of secondary interactions but may vary depending upon the nature of the solution in which it is dissolved.
Gender‐specific factors associated with the suicidal ideation of children in Taiwan: A large‐scale cross‐sectional study
Authors: Huang Hsiao‐Ling , Peng Wu‐Der , Lin Ying‐Chun , Lee Chien‐Hung , Hu Chih‐Yang , Huang Shun‐Te 
Published: July 2017

AbstractWe examined the relationship between suicidal ideation (SI) and the depressed mood, life stress and parenting styles in children. A large‐scale survey was conducted including 5328 children from 65 elementary schools in Taiwan. SI was measured by asking children if any suicidal thoughts had occurred in the previous month. A series of regression models was analysed separately for male and female students. Compared with boys, girls demonstrated a higher proportion of SI. Among boys, SI was significantly associated with a high level of perceived environmental stress (adjusted odds ratio [aOR] = 2.61), a high degree of depressed mood (aOR = 2.39), authoritative (aOR = 1.72) and authoritarian (aOR = 2.53) parenting styles and two or more life‐stress events (aOR = 1.45). A high level of perceived environmental stress (aOR = 2.09), a high degree of depressed mood (aOR = 2.89) and an authoritarian parenting style (aOR = 1.76) were significantly associated with the SI in girls. Gender‐specific interventions aimed at preventing SI must enhance support systems at school and at home, particularly for students who suffer from a high degree of stress and depressed mood, and are subjected to an authoritarian parenting style.