bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, characterization, and in vitro biocompatibility study of novel disulfide cross‐linked hydrogels based on poly(amic acid)
Authors: Peng Kun , Sun Jiaoxia , Wang Yuanliang , Li Yuxiao , Zhang Bingbing , Wang Bin 
Published: May 2014

ABSTRACTIn this study, novel disulfide cross‐linked hydrogels were designed and synthesized. First, ethylenediaminetetraacetic dianhydride reacted with butanediamine and amino‐terminated polyethylene glycol via N‐acylation reaction to give biocompatible poly(amic acid) (PAA) with pendant carboxyl groups; then, the amino groups of cystamine reacted with carboxyl groups of PAA to generate disulfide cross‐linked network polymer (PAA‐SS). Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance imaging, gel permeation chromatography with multiangle laser light scattering, potentiometric titration, rheology, hydrolytic degradation, morphology, porosity, and in vitro biocompatibility studies were used to qualitatively and quantitatively characterize the obtained polymers. The results indicated that the equilibrium swelling ratio of the PAA‐SS decreased with the increase in Rm. The PAA‐SS provided good mechanical strength to maintain their integrity, and the storage modules (G′) of the hydrogels can be adjusted by Rm. The PAA‐SS presented co‐continuum pores, and the pore size correlated with the cross‐linking degree. The degradation of PAA‐SS could be controlled by regulating the concentration of dithiothreitol. Particularly, the PAA‐SS possessed an excellent biocompatibility, as the average proliferating rate of osteoblasts on PAA‐SS was appreciably higher than that on PAA and glass coverslips. In conclusion, the above obtained results demonstrate that the performance of the PAA‐SS outbalance and facilitate the application in biomedical region, particularly in bone tissue regeneration. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40930.
The Effect of Atrazine Administered by Gavage or in Diet on the LH Surge and Reproductive Performance in Intact Female Sprague‐Dawley and Long Evans Rats
Authors: Foradori Chad D. , Sawhney Coder Prägati , Tisdel Merrill , Yi Kun Don , Simpkins James W. , Handa Robert J. , Breckenridge Charles B. 
Published: May 2014

Atrazine (ATR) blunts the hormone‐induced luteinizing hormone (LH) surge, when administered by gavage (50–100 mg/kg/day for 4 days), in ovariectomized rats. In this study, we determined if comparable doses delivered either by gavage (bolus dose) or distributed in diet would reduce the LH surge and subsequently affect fertility in the intact female rat. ATR was administered daily to intact female Sprague‐Dawley (SD) or Long Evans (LE) rats by gavage (0, 0.75 1.5, 3, 6, 10, 12, 50, or 100 mg/kg/day) or diet (0, 30, 100, 160, 500, 660, or 1460 ppm) during one complete 4‐day estrous cycle, starting on day of estrus. Estrous status, corpora lutea, ova, and LH plasma concentrations were evaluated. A second cohort of animals was mated on the fourth treatment day. Fertility metrics were assessed on gestational day 20. A higher portion of LE rats had asynchronous estrous cycles when compared to SD rats both during pretreatment and in response to ATR (≥50 mg/kg). In contrast, bolus doses of ATR (≥50 mg/kg) inhibited the peak and area under the curve for the preovulatory LH surge in SD but not LE animals. Likewise, only bolus‐treated SD, not LE, rats displayed reduced mean number of corpora lutea and ova. There were no effects of ATR administered by gavage on mating, gravid number, or fetus number. Dietary administration had no effect on any reproductive parameter measured. These findings indicate that short duration, high‐bolus doses of ATR can inhibit the LH surge and reduce the number of follicles ovulated; however, dietary administration has no effect on any endocrine or reproductive outcomes
In situ detection of salicylic acid binding sites in plant tissues
Authors: Liu Jing‐Wen , Deng Da‐Yi , Yu Ying , Liu Fang‐Fei , Lin Bi‐Xia , Cao Yu‐Juan , Hu Xiao‐Gang , Wu Jian‐Zhong 
Published: May 2014

AbstractThe determination of hormone‐binding sites in plants is essential in understanding the mechanisms behind hormone function. Salicylic acid (SA) is an important plant hormone that regulates responses to biotic and abiotic stresses. In order to label SA‐binding sites in plant tissues, a quantum dots (QDs) probe functionalized with a SA moiety was successfully synthesized by coupling CdSe QDs capped with 3‐mercaptopropionic acid (MPA) to 4‐amino‐2‐hydroxybenzoic acid (PAS), using 1‐ethyl‐3‐(3‐dimethyllaminopropyl) carbodiimide (EDC) as the coupling agent. The probe was then characterized by dynamic light scattering and transmission electron microscopy, as well as UV/vis and fluorescence spectrophotometry. The results confirmed the successful conjugation of PAS to CdSe QDs and revealed that the conjugates maintained the properties of the original QDs, with small core diameters and adequate dispersal in solution. The PAS–CdSe QDs were used to detect SA‐binding sites in mung bean and Arabidopsis thaliana seedlings in vitro and in vivo. The PAS–CdSe QDs were effectively transported into plant tissues and specifically bound to SA receptors in vivo. In addition, the effects of the PAS–CdSe QDs on cytosolic Ca2+ levels in the tips of A. thaliana seedlings were investigated. Both SA and PAS–CdSe QDs had similar effects on the trend in cytosolic‐free Ca2+ concentrations, suggesting that the PAS–CdSe QDs maintained the bioactivity of SA. To summarize, PAS–CdSe QDs have high potential as a fluorescent probe for the in vitro/in vivo labeling and imaging of SA receptors in plants. Copyright © 2014 John Wiley & Sons, Ltd.
Preparation and optical properties of alloyed ZnxCd1‐xS/alginate core/shell nanoparticles
Authors: Wang Liping , Sun Yujie 
Published: May 2014

AbstractZnxCd1‐xS/alginate core/shell nanoparticles were synthesized via a colloidal route by reacting zinc and cadmium ions with sulfide ions, followed by coating with alginate. The crystal structure, morphology, size and optical properties of the core/shell nanoparticles were characterized by X‐ray diffraction, transmission electron microscopy, UV/vis and photoluminescent spectra, respectively. The ZnxCd1‐xS nanoparticles are spherical and have a cubic structure with a mean crystalline size of 2–4 nm. The band gap of ZnxCd1‐xS/alginate core/shell nanoparticles increases with increasing Zn/Cd molar ratio, and the UV/vis absorption blue‐shifts correspondingly. Two emissions related to zinc and sulfide ion vacancies were observed for the ZnxCd1‐xS/alginate core/shell nanoparticles due to the surface changes from the alginate coating. A cadmium‐related emission was observed for both the uncovered ZnxCd1‐xS and ZnxCd1‐xS/alginate core/shell nanoparticles, which has a significant blue‐shift with increasing Zn/Cd molar ratio. Copyright © 2014 John Wiley & Sons, Ltd.
An improved dynamic method to measure kLa in bioreactors
Authors: Damiani Andrew L. , Kim Min Hea , Wang Jin 
Published: May 2014

ABSTRACTAn accurate measurement or estimation of the volumetric mass transfer coefficient kLa is crucial for the design, operation, and scale up of bioreactors. Among different physical and chemical methods, the classical dynamic method is the most widely applied method to simultaneously estimate both kLa and cell's oxygen utilization rate. Despite several important follow‐up articles to improve the original dynamic method, some limitations exist that make the classical dynamic method less effective under certain conditions. For example, for the case of high cell density with moderate agitation, the dissolved oxygen concentration barely increases during the re‐gassing step of the classical dynamic method, which makes kLa estimation impossible. To address these limitations, in this work we present an improved dynamic method that consists of both an improved model and an improved procedure. The improved model takes into account the mass transfer between the headspace and the broth; in addition, nitrogen is bubbled through the broth when air is shut off. The improved method not only enables a faster and more accurate estimation of kLa, but also allows the measurement of kLa for high cell density with medium/low agitation that is impossible with the classical dynamic method. Scheffersomyces stipitis was used as the model system to demonstrate the effectiveness of the improved method; in addition, experiments were conducted to examine the effect of cell density and agitation speed on kLa. Biotechnol. Bioeng. 2014;111: 2120–2125. © 2014 Wiley Periodicals, Inc.
Problem‐solving Test: DNA manipulation with alkaline phosphatase and polynucleotide kinase
Authors: Szeberényi József 
Published: May 2014

AbstractTerms to be familiar with before you start to solve the test: 3′‐ and 5′‐ends of DNA fragments, plasmids, restriction endonucleases, agarose gel electrophoresis, linear and circular DNA, superhelical DNA, blunt and sticky ends, DNA ligase, nuclease, [γ‐32P] ATP, and radioactive labeling. © 2014 by The International Union of Biochemistry and Molecular Biology, 42(4):348–350, 2014.
How Do Environmental Violation Events Harm Corporate Reputation?
Authors: Zou H. L. , Zeng R. C. , Zeng S. X. , Shi Jonathan J. 
Published: May 2014

AbstractThis study, based on attribution theory, provides empirical evidence for how environmental violation events (EVEs) damage corporate reputation, using media reputation as a proxy. Hypotheses are developed to address the influences of violating firms’ past environmental behaviors and ownership on the reputational effect of EVEs. The results show that firms with a history of unfavorable behaviors (precedent environmental violation) are deemed by the media to be more culpable for adverse environmental events and consequently suffer more damage to their reputation, while for firms with a favorable environmental record (environmental awards and honors gained) the reputational harm of an EVE is alleviated to some extent. EVEs cause more reputational damage to foreign‐owned enterprises than to domestic‐owned firms. These findings reveal that certain company behaviors could exert an indirect effect on a firm's reputation by influencing public perception of later relevant behaviors, and imply a discriminatory treatment in a host country for foreign‐owned enterprises. Copyright © 2014 John Wiley & Sons, Ltd and ERP Environment
A haptic‐enabled novel approach to cardiovascular visualization
Authors: Yasmin Shamima , Du Nan , Chen James , Feng Yusheng 
Published: May 2014

ABSTRACTIntravascular ultra sound (IVUS) imaging technique is widely used for the detection of plaque deposit inside coronary artery wall. Adequate detection of plaque deposit is necessary for further treatment of the patient, but image by image analysis, nevertheless, is cumbersome. In this paper, we proposed a fully automatic novel method for coronary artery visualization, which takes as an input a number of intravascular ultrasound images to construct the 3D model of coronary artery wall where the plaque deposit is demarcated in a rapid 3D rendering environment. This 3D visualization of coronary artery model has been enhanced in a haptic environment where the user is not only able to visualize the fatty plaque deposit but is also able to feel and differentiate stiffness of plaque deposit as well as soft, elastic property of normal artery through a virtual tour along the artery pathway. Copyright © 2014 John Wiley & Sons, Ltd.
Cannabis use among juvenile detainees: Typology, frequency and association
Authors: Grigorenko Elena L. , Edwards Laurel , Chapman John 
Published: May 2014

AbstractBackgroundAs both lifetime and daily use of marijuana remain prevalent among US adolescents and are likely to increase, given the legalisation of marijuana in a number of states, their correlates with other negative (including delinquent) behaviours have been studied. Most of this research has been carried out with general‐population‐based samples. Thus, little is known about this association among court‐involved and detained juveniles.AimsThis study aimed to assess lifetime and daily marijuana use among detainees aged 10–16 years. Our hypotheses were that such use would be higher among youth who had been in detention than in general population samples and that it would be associated with other mental health indicators and criminal justice indicators, such as total number of detentions and number and types of charges.MethodsThe records of a random 20% sample of all juveniles in detention in Connecticut's state facilities were studied. Data extracted included self‐reported information on lifetime and daily use of marijuana, mental health indicators, lifetime psychiatric diagnoses and criminal justice indicators.ResultsRates of both lifetime (54%) and daily (16%) use of marijuana in this sample of 371 young people were substantially higher than previous studies have reported in general population samples. As a group, daily users of marijuana demonstrated a more negative mental health profile but did not differ from the rest of the sample in their criminal justice indicators.Conclusions/implications for practiceOur findings suggest that it is unlikely that cannabis use by young offenders can serve as an independent factor in understanding the frequency and severity of delinquency, although it might be associated with the severity of mental health disorder or dysfunction among them. Copyright © 2014 John Wiley & Sons, Ltd.
Structural and Stereochemical Studies of a Tetralin Norsesquiterpenoid from Ligularia kangtingensis
Authors: Xie Guangbo , Tian Jin , Kövér Katalin E. , Mándi Attila , Kurtán Tibor 
Published: May 2014

ABSTRACTA chiral tetralin norsesquiterpenoid, ligukangtinol, was isolated from the plant Ligularia kangtingensis. Its planar structure was determined by extensive analysis of spectroscopic data (MS, IR, and NMR), and (1S,3R) absolute configuration of the tetralin ring was established by TDDFT‐ECD calculations of the solution conformers. Conformational analysis and ECD calculations proved that the semiempirical helicity rules of 6‐hydroxytetralins correlating the 1Lb Cotton effect and P/M helicity of the fused carbocyclic ring correctly predicts the absolute configuration and thus can be used for the configurational assignment of related substituted tetralin derivatives. Chirality 26:574–579, 2014. © 2014 Wiley Periodicals, Inc.
On the Interplay Between Chirality and Exciton Coupling: A DFT Calculation of the Circular Dichroism in π‐Stacked Ethylene
Authors: Norman Patrick , Linares Mathieu 
Published: May 2014

ABSTRACTThe chirality of stacked weakly interacting π‐systems was interpreted in terms of Frenkel exciton states and the formation of excitonic circular dichroism (CD) bands was monitored for ethylene stacks of varying sizes. Convergence of CD bands with respect to the system size was observed for stacks involving around 10 molecules. By means of rotation around the C–C double bond in ethylene, chirality was induced in the monomeric system and which was shown to dominate the spectral responses, even for polymer aggregates. In helical assemblies of chiral entities, there will always be a mix of excitonic and monomeric contributions to the CD signal and it is demonstrated that the complex polarization propagator approach in combination with Density Functional Theory is a suitable method to address this situation. Chirality 26:483–489, 2014. © 2014 Wiley Periodicals, Inc.
Mixed‐Ligand Mononuclear Copper(II) Complex: Crystal Structure and Anticancer Activity
Authors: Qin Xiu‐Ying , Liu Ya‐Nan , Yu Qian‐Qian , Yang Li‐Cong , Liu Ying , Zhou Yan‐Hui , Liu Jie 
Published: May 2014

AbstractA novel copper(II) complex with mixed ligands including β‐[(3‐formyl‐5‐methyl‐2‐hydroxy‐benzylidene)amino]propionic acid anion and 1,10′‐phenanthroline was synthesized, and its crystal structure was thoroughly characterized. It exerted excellent inducing apoptosis, anti‐angiogenesis and antiproliferative properties in vitro. The complex can bind human serum albumin (HSA) at physiological pH conditions. Remarkably, it can induce formation of the mixed parallel/antiparallel G‐quadruplex structures in the G‐rich sequence of the proximal vascular endothelial growth factor (VEGF) promoter, and stabilize these G‐quadruplex structures, which provide an opportunity for anti‐angiogenesis chemotherapeutics. Furthermore, the complex showed a strong uptake, and exhibited multiple anticancer functions by inhibiting the expression of p‐Akt and p‐Erk1/2 proteins and by upregulating the levels of reactive oxygen species (ROS). Because of the reported results, this new copper(II) complex qualifies itself as a potential anticancer drug candidate.
FluMapper: A cyberGIS application for interactive analysis of massive location‐based social media
Authors: Padmanabhan Anand , Wang Shaowen , Cao Guofeng , Hwang Myunghwa , Zhang Zhenhua , Gao Yizhao , Soltani Kiumars , Liu Yan 
Published: May 2014

SUMMARYSocial media have experienced a spectacular rise in popularity, attracting hundreds of millions of users and generating unprecedented amount of content that increasingly contain location and place information. Collectively, the massive location information in these data provides an excellent opportunity to better understand many geographic phenomena and geospatial dynamics in a timely fashion. Recent studies capitalizing on social networking and media data show significant societal impacts in many areas including prediction of stock market and infectious disease surveillance. However, because location‐based social media data are often massive, generated dynamically, and unstructured, significant computation, data, and visualization challenges need to be resolved. This research aims to demonstrate the use of massive social media data to interactively analyze spatiotemporal events across spatial and temporal scales, by establishing a data‐driven framework using cyberGIS—geographic information systems (GIS) based on advanced cyberinfrastructure—to resolve aforementioned challenges. Specifically, FluMapper—an application on the CyberGIS Gateway—is employed as a case study to demonstrate the data‐driven framework and seamless integration of massive location‐based social media data and spatial analytical services within the online problem solving environment of the Gateway. FluMapper presents integrated results from two complementary spatial analyses: (i) an interactive exploration of spatial distribution of flu risk and (ii) dynamic mapping of movement patterns, across multiple spatial, and temporal scales. The seamless integration of these two analyses through the framework illustrates the potential of cyberGIS to resolve the compute and data challenges of analyzing near real‐time social media data in an efficient and scalable manner and to support interactive visualization. Copyright © 2014 John Wiley & Sons, Ltd.
Synthesis and Characterization of Single‐Side Organically Grafted Anderson‐Type Polyoxometalates
Authors: Ai Hui , Wang Yang , Li Bao , Wu Lixin 
Published: May 2014

AbstractFive single‐side organic decorated Anderson‐type molybdoaluminates have been synthesized from the reaction of the Na3(H2O)6[Al(OH)6Mo6O18]·2H2O cluster and RC(CH2OH)3 ligands [R = CH2OH, NH2, CH2CH3, NHCH2COOH, CH2OCH2C(CH2OH)3], followed by the addition of TBA·Br {TBA = [N(C4H9)4]+}. The prepared compounds possess an identical Anderson‐type structural frame in each case, wherein three of the six hydroxy groups surrounding the AlIII heteroatom are substituted by one RC(CH2OH)3 group, forming asymmetric single‐sided organically decorated clusters. The compounds demonstrate the simplest synthesis of covalent organic decoration for the single‐sides of molybdoaluminates. All the prepared compounds in the present study were synthesized in aqueous solution and characterized by elemental and TG analysis, IR and 1H NMR spectroscopy, and single‐crystal X‐ray diffraction analysis. In addition, the supramolecular structures of these compounds based on the hydrogen bonding have also been discussed. The method reported here provides a common approach for the asymmetric functionalization of Anderson‐type molybdoaluminates.
Four Molecular Superconductors Isolated as Nanoparticles
Authors: de Caro Dominique , Faulmann Christophe , Valade Lydie , Jacob Kane , Chtioui Imane , Foulal Soukaina , de Caro Pascale , Bergez‐Lacoste Manon , Fraxedas Jordi , Ballesteros Belén , Brooks James S. , Steven Eden , Winter Laurel E. 
Published: May 2014

Abstract(TMTSF)2PF6 and (TMTSF)2ClO4 Bechgaard salts, (BEDT‐TTF)2I3, and TTF[Ni(dmit)2]2 [TMTSF = tetramethyltetraselenafulvalene; BEDT‐TTF = bis(ethylenedithio)tetrathiafulvalene; TTF = tetrathiafulvalene; dmit = 1,3‐dithiole‐2‐thione‐4,5‐dithiolate] are among the most popular molecular superconductors. They are grown as nanoparticles that exhibit properties in agreement with those of the bulk. The shape, size, and homogeneity of particles depend on the stabilizing agent and synthesis conditions. We report on the more recent conditions investigated (i) to produce nanoparticles of 35 nm for β‐(BEDT‐TTF)2I3, (ii) to reduce the particle size to 10–15 nm for TTF[Ni(dmit)2]2 and 3–5 nm for (TMTSF)2ClO4, and (iii) to improve the growth duration from days to one hour for (TMTSF)2PF6. Finally, we report evidence of superconductivity in (TMTSF)2ClO4 particles.
Evolution of BODIPY Dyes as Potential Sensitizers for Dye‐Sensitized Solar Cells
Authors: Singh Surya Prakash , Gayathri Thumuganti 
Published: May 2014

AbstractEnhancement of light‐harvesting efficiency (LHE) in the red/near‐IR (NIR) region (600–1000 nm) of the solar spectrum is a challenge to improvement of the photovoltaic performances of dye‐sensitized solar cells (DSSCs). Therefore, design and development of effective red/NIR photosensitizers are currently a hot topic in DSSCs. BODIPY dyes can offer magnificent characteristics such as sharp and moderately strong absorption, large quantum yields, long excited state lifetimes, good solubility and easy chromatographic separation. From this perspective, recent progress in BODIPY‐sensitized solar cells is reviewed.
One‐Pot Transformation of Methylarenes into Aromatic Nitriles with Inorganic Metal‐Free Reagents
Authors: Kawagoe Yuhsuke , Moriyama Katsuhiko , Togo Hideo 
Published: May 2014

AbstractVarious methylarenes were transformed into the corresponding aromatic nitriles in good to moderate yields by the treatment with aq. HBr and aq. H2O2, followed by reaction with molecular iodine and aq. ammonia in a one‐pot procedure. The present reaction is a useful, practical, transition‐metal‐free, and organic‐reagent‐free method for the preparation of aromatic nitriles from methylarenes.
Positive and extensive intergroup contact in the past buffers against the disproportionate impact of negative contact in the present
Authors: Paolini Stefania , Harwood Jake , Rubin Mark , Husnu Shenel , Joyce Nicholas , Hewstone Miles 
Published: May 2014

AbstractNegative (vs positive) intergroup contact may have a disproportionately large impact on intergroup relations because of valence‐salience effects, whereby negative contact causes higher category salience (Paolini, Harwood, & Rubin, 2010). One correlational and three experimental studies in three conflict areas (Northern Ireland, Arizona's border area, and Cyprus; Ns = 405, 83, 76, and 91) tested the moderation of these valence‐salience effects by individuals' histories of outgroup contact. Consistent with a perceived fit principle valence‐salience effects of face‐to‐face, television‐mediated, and imagined contact held among individuals with negative or limited histories of outgroup contact; these effects were significantly reduced or nonsignificant among individuals with positive or extensive past outgroup contact. These moderation effects suggest that positive and diverse intergroup contact in the past buffers against the harmful effects of negative contact experiences in the present, thus limiting the potential for negative spiralling of intergroup relations. Copyright © 2014 John Wiley & Sons, Ltd.