bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Photon‐Fueled Gate‐Like Delivery System Using i‐Motif DNA Functionalized Mesoporous Silica Nanoparticles
Authors: He Dinggeng , He Xiaoxiao , Wang Kemin , Cao Jie , Zhao Yingxiang 
Published: June 2012

AbstractA novel photon‐fueled gate‐like mesoporous silica nanoparticles (MSN)‐based delivery system is reported. In this system, the malachite green carbinol base (MGCB) is immobilized on the nanochannel wall of MSN as a light‐induced hydroxide ion emitter and i‐motif DNA is grafted on the surface of MSN as a cap. Photoirradiation with 365 nm wavelength UV light makes MGCB molecules dissociate into malachite green (MG) cations and OH− ions, which induce the i‐motif DNA to unfold into the single‐stranded form due to the increase of the pH in the solution. Therefore, the pores are uncapped and the entrapped guest molecules are released. After the light is turned off, the MG cations recombine with the OH− ions and return to the MGCB forms. The pH value thus decreases and the single‐stranded DNA switches back to i‐motif structure to cap the pore again. Because of the photon‐fueled MGCB‐dependent DNA conformation changes, the i‐motif DNA‐gated switch can be easily operated by turning the light on or off. Importantly, the opening/closing protocol is highly reversible and a partial cargo release can be easily achieved at will. This proof‐of‐concept may promote the application of DNA in the controlled release and can also provide a way to design various photon‐fueled controlled‐release systems using a combination of some photoirradiated pH‐jump systems and other kinds of pH‐sensitive linkers.
Synthesis and characterization of a novel acetylene‐ and maleimide‐terminated benzoxazine and its high‐performance thermosets
Authors: Gao Yu , Huang Farong , Zhou Yan , Du Lei 
Published: June 2012

AbstractA novel acetylene‐ and maleimide‐terminated benzoxazine, 3‐(3‐ethynylphenyl)‐3,4‐dihydro‐2H‐6‐(N‐maleimido)‐1,3‐benzoxazine (MBZ‐apa), was successfully synthesized with N‐(4‐hydroxyphenyl)maleimide, paraformaldehyde, and 3‐aminophenylacetylene. The structure of the benzoxazine is confirmed by FTIR and 1H‐NMR spectroscopies. MBZ‐apa is easily dissolved in common organic solvents. Differential scanning calorimetry (DSC) was used to study thermal cross‐linking behavior of MBZ‐apa. The DSC curve shows only a single exothermic peak due to the oxazine ring‐opening polymerization and the polymerization of the acetylene and maleimide groups occurring simultaneously in the same temperature range. Dynamic mechanical analyses (DMA) reveals that the novel polybenzoxazine exhibits high glass‐transition temperature (Tg) (ca. 348°C). The storage modulus arrives at 4.5 GPa in the range of room temperature to 330°C. The polybenzoxazine exhibits good thermal stability as evidenced by thermogravimetric analysis (TGA). Pyrolysis‐gas chromatography/mass spectrometry (Pyrolysis‐GC/MS) was employed to characterize the polybenzoxazine. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Using a process‐based catchment‐scale model for enhancing field‐based stream assessments and predicting stream fish assemblages
Authors: kautza Adam , Sullivan S. MaŽeika P. 
Published: June 2012

ABSTRACT

Catchment‐modelling techniques, although not yet widely used in biological contexts, may be a valuable tool in the management and conservation of stream fishes. This study was undertaken to evaluate the potential of a catchment‐scale hydrologic model, the Soil and Water Assessment Tool (SWAT), to explain characteristics of stream fish assemblages and to enhance current field‐based stream assessments.
Stream fish assemblages, instream habitat, geomorphology, and water quality were surveyed in 16 study catchments in Ohio, USA. Subsequently, SWAT was used to model stream discharge, sediment flux and concentration, and nitrogen and phosphorus yields for each catchment.
Principal component analysis (PCA) and multiple linear regression were used to explore potential relationships between environmental factors (both reach‐level measurements and SWAT‐modelled catchment‐scale processes) and fish assemblage descriptors assessed within the framework of an Ohio fish‐based Index of Biotic Integrity (IBI).
Reach‐level factors contributed to three of the four significant regression models, explaining 12% to 14% of the variation in fish species richness, the number of darter (Etheostoma) species, and the number of sensitive/intolerant species. SWAT‐modelled parameters including minimum and mean annual flow and sediment yields explained significant variation in total IBI scores (57%), species richness (63%), the number of darter species (60%), and the number of sensitive/intolerant species (61%).
The results support the utility of SWAT as a complement to field‐based surveys. It is proposed that process‐based catchment‐modelling techniques such as SWAT could improve stream fish management and conservation efforts when used as a screening tool to target streams and catchments for subsequent field surveys and as a method to model potential impacts to stream ecosystems and fish assemblages in highly sensitive areas and/or inaccessible catchments. Copyright © 2012 John Wiley & Sons, Ltd.
The relationship between water quality and indigenous and alien crayfish distribution in the Czech Republic: patterns and conservation implications
Authors: Svobodová Jitka , Douda Karel , Štambergová Monika , Picek JiŘí , Vlach Pavel , Fischer David 
Published: June 2012

ABSTRACT

Although the noble crayfish (Astacus astacus L.) and stone crayfish (Austropotamobius torrentium Schr.) are critically endangered European species, their water quality requirements are not sufficiently known.
This study aimed to investigate the physico‐chemical tolerance range of the noble and stone crayfish in the Czech Republic compared with those of the invasive spiny‐cheek crayfish (Orconectes limosus Raf.). At 1008 sites with crayfish either absent or present, the following 18 physico‐chemical variables were investigated: dissolved oxygen, pH, BOD5, CODCr, ammonia, ammonium ions, nitrite, nitrate ions, zinc, copper, iron, aluminium, calcium, sulphates, chlorides, total phosphorus, suspended solids, and conductivity.
For the noble and stone crayfish, only minor differences in water quality were found. This indicates that the water quality requirements of these indigenous crayfish are likely to be very similar. However, significant differences in water quality were observed between locations inhabited by indigenous crayfish and those inhabited by the invasive spiny‐cheek crayfish.
Based on these findings, we hypothesize that the invasive species is able to survive in locations with lower water quality. Simple logistic regression models were then used to examine relationships between the presence or absence of noble crayfish and each evaluated water quality variable. The presence of this species was related significantly with those variables that indicate nutrient enrichment (particularly ammonium, BOD5, and nitrite) and to iron.
Overall, although the indigenous crayfish species were found at several sampling sites that had impaired water quality, the statistical analyses indicate that the indigenous species require water of high quality. Improvement in water quality is therefore an important step in sustaining indigenous crayfish populations. Copyright © 2012 John Wiley & Sons, Ltd.
Politeness improves interactivity in dense crowds
Authors: Allen Brian F. , Magnenat‐Thalmann Nadia , Thalmann Daniel 
Published: June 2012

ABSTRACTTraversing dense crowds can be challenging, but it is especially difficult in a virtual environment where the user is limited to simple input devices. Predicting near‐future user movements with a hidden Markov model allows nearby autonomous agents to react politely, that is, to specifically avoid impeding the movement of the user. This predictive model and simple avoidance scheme are tested by six subjects in 360 short interactive games and by a 10‐participant two‐alternative forced choice questionnaire. Polite agents are found to significantly improve the player's ability to navigate quickly and without collision, and the resulting character movements showed increased naturalness for two of the three game scenarios. Copyright © 2012 John Wiley & Sons, Ltd.
The Syntheses of new Camphorsulfonylated Ligands Derived from 2‐Amino‐2′‐Hydroxy‐1,1′‐Binaphthyl and Their Enantioselectivities in the Addition of Dialkylzinc Reagents to Aldehydes
Authors: Bian Guangling , Huang Huayin , Zong Hua , Song Ling 
Published: June 2012

ABSTRACTA series of new camphorsulfonylated ligands derived from chiral 2‐amino‐2′‐hydroxy‐1,1′‐binaphthyl (NOBIN) and (+)‐camphorsulfonic acid were synthesized by a short and simple synthetic sequence, and their enantioselective catalytic activities were assessed in the nucleophilic addition reaction of dialkylzinc reagents to aldehydes in the presence of titanium tetraisopropoxide. The most efficient ligand, N‐hydroxycamphorsulfonylated (S)‐NOBIN, gave (S)‐addition products with good yields and up to 87% of ee value. The 1H nuclear magnetic resonance (NMR) and 13C NMR results of the titanium titration experiments on this ligand indicate that the most likely catalytic reactive species involved in this catalytic asymmetric addition is a bimetallic titanium complex. A possible catalytic reaction mechanism is proposed. Chirality 24:825–832, 2012. © 2012 Wiley Periodicals, Inc.
The Electrochemistry of Nanostructured Titanium Dioxide Electrodes
Authors: Berger Thomas , Monllor‐Satoca Damián , Jankulovska Milena , Lana‐Villarreal Teresa , Gómez Roberto 
Published: June 2012

AbstractSeveral of the multiple applications of titanium dioxide nanomaterials are directly related to the introduction or generation of charge carriers in the oxide. Thus, electrochemistry plays a central role in the understanding of the factors that must be controlled for the optimization of the material for each application. Herein, the main conceptual tools needed to address the study of the electrochemical properties of TiO2 nanostructured electrodes are reviewed, as well as the electrochemical methods to prepare and modify them. Particular attention is paid to the dark electrochemical response of these nanomaterials and its direct connection with the TiO2 electronic structure, interfacial area and grain boundary density. The physical bases for the generation of currents under illumination are also presented. Emphasis is placed on the fact that the kinetics of charge‐carrier transfer to solution determines the sign and value of the photocurrent. Furthermore, methods for extracting kinetic information from open‐circuit potential and photocurrent measurements are briefly presented. Some aspects of the combination of electrochemical and spectroscopic measurements are also dealt with. Finally, some of the applications of TiO2 nanostructured samples derived from their electrochemical properties are concisely reviewed. Particular attention is paid to photocatalytic processes and, to a lesser extent, to photosynthetic reactions as well as to applications related to energy from the aspects of both saving (electrochromic layers) and accumulation (batteries). The use of TiO2 nanomaterials in solar cells is not covered, as a number of reviews have been published addressing this issue.
Immune system gene dysregulation in autism and schizophrenia
Authors: Michel Maximilian , Schmidt Martin J. , Mirnics Karoly 
Published: June 2012

AbstractGene*environment interactions play critical roles in the emergence of autism and schizophrenia pathophysiology. In both disorders, recent genetic association studies have provided evidence for disease‐linked variation in immune system genes and postmortem gene expression studies have shown extensive chronic immune abnormalities in brains of diseased subjects. Furthermore, peripheral biomarker studies revealed that both innate and adaptive immune systems are dysregulated. In both disorders symptoms of the disease correlate with the immune system dysfunction; yet, in autism this process appears to be chronic and sustained, while in schizophrenia it is exacerbated during acute episodes. Furthermore, since immune abnormalities endure into adulthood and anti‐inflammatory agents appear to be beneficial, it is likely that these immune changes actively contribute to disease symptoms. Modeling these changes in animals provided further evidence that prenatal maternal immune activation alters neurodevelopment and leads to behavioral changes that are relevant for autism and schizophrenia. The converging evidence strongly argues that neurodevelopmental immune insults and genetic background critically interact and result in increased risk for either autism or schizophrenia. Further research in these areas may improve prenatal health screening in genetically at‐risk families and may also lead to new preventive and/or therapeutic strategies. © 2012 Wiley Periodicals, Inc. Develop Neurobiol, 2012
Bubble collapse in compressible fluids using a spectral element marker particle method. Part 2. Viscoelastic fluids
Authors: Lind S. J. , Phillips T. N. 
Published: June 2012

SUMMARYThis paper is concerned with the development of a high‐order numerical scheme for two‐phase viscoelastic flows. In the companion paper, herein referred to as Part 1, the scheme is applied to the modelling of two‐phase Newtonian flows. The particular problem of the collapse of a 2D bubble in the vicinity of a rigid boundary is considered. Attention is given to the construction of the most general form of the compressible Oldroyd B model that is consistent with the compressible Newtonian and upper‐convected Maxwell models in the appropriate limits. The governing equations are discretized using the spectral element method, and the two phases are modelled using a marker particle method. A comprehensive set of results is presented for the problem of bubble collapse near a rigid wall, and qualitative agreement is obtained with other numerical studies and experimental observations. Viscoelastic effects that are predicted include increased bubble oscillation with increasing Weissenberg number and considerable bubble deformation and cusping near the wall. Most importantly, it has been shown that viscoelasticity has the ability to prevent jet formation and therefore is likely to have a mitigating effect on cavitation damage. Copyright © 2012 John Wiley & Sons, Ltd.
Electrooxidation of Methanol and Ethylene Glycol Mixture on Platinum and Palladium in Alkaline Medium
Authors: Li Z. Y. , Liang Y. J. , Jiang S. P. , Shan X. D. , Lin M. L. , Xu C. W. 
Published: June 2012

AbstractThe performance of mixture of methanol and ethylene glycol (EG) oxidation has been studied on both Pt and Pd electrodes in alkaline medium. The activity of EG oxidation is better than that of methanol oxidation and the stability of EG oxidation is better than that of methanol and ethanol oxidation on the Pd electrode. The onset potential for ethanol oxidation is more negative 200 mV than that of EG, however the stability of EG oxidation on the Pd electrode is better than that of ethanol oxidation. The performance of methanol oxidation improves pronouncedly by adding a small amount of EG on both Pt and Pd electrodes. The onset potential and peak potential of mixture of methanol and EG oxidation are close to or more negative than that of sole methanol and EG oxidation on the Pd electrode. The mixture of methanol and EG is more easily to be electrochemically oxidized and gives a better performance than sole methanol and EG on the Pd electrode. The results show that the mixture of methanol and EG is a promising candidate as fuel in direct alcohol fuel cells.
How Did We Learn Best? A Retrospective Survey of Clinical Psychology Training in the United Kingdom
Authors: Nel Pieter W. , Pezzolesi Cinzia , Stott Dave J. 
Published: June 2012

ObjectivesThis U.K.‐based study aimed to investigate qualified clinical psychologists’ perceptions of the value and usefulness of the learning activities experienced during their training in clinical psychology.DesignMembers (N = 357) of the Division of Clinical Psychology of the British Psychological Society (BPS) completed a self‐report questionnaire about their training as clinical psychologists.ResultsThe results indicate that most clinical psychologists believe that they learnt mainly through doing and by observing others’ clinical practice. They also highlight the importance of the learning relationship and the value of personal therapy for learning.ConclusionsThe findings point to the need for more training of trainers, especially clinical supervisors. They also draw attention to the need for more research to establish which learning activities contribute most / least to trainees’ developing competence.
GULLY FAN MORPHODYNAMICS IN A SMALL CATCHMENT IN THE EASTERN CAPE, SOUTH AFRICA
Authors: Manjoro M. , Rowntree K. , Kakembo V. , Foster I. D. L. 
Published: June 2012

ABSTRACTFans, in association with hillslope gullies and badlands and their impact on the catchment sediment cascade, slope‐channel connectivity and local landscape evolution, have been reported in diverse geomorphic environments. However, research on the development and morphodynamics of gully fans is still in its infancy in South Africa. An investigation was undertaken in mid‐slope discontinuous gullies in the Eastern Cape Province of South Africa using field surveys and sediment source fingerprinting techniques to establish the dynamics of fan systems and their impacts on‐slope sediments. Findings showed that a sediment core collected from the upper region of the fan was composed mainly of sediment mobilised from subsurface sources, whereas that from the lower region of the fan consisted mostly of sediment from surface sources. 137Cs data were consistent with the sediment source fingerprinting results, confirming the respective surface and subsurface origins of the sediment in the sampled cores. Additionally, 137Cs pointed to the recent formation of the fan. Geomorphic reconstruction of the fan did not support a cut and fill mode of gully fan development. Rather, the fan formed as a consequence of discontinuous gullies in the mid‐slope leading to on‐slope sediment deposition and slope‐channel decoupling. It was also observed that hillslope sediment storage in the gully fan is temporally variable. Changes in the balance of morphodynamic processes may lead to sediment flushing and slope‐channel coupling. Copyright © 2012 John Wiley & Sons, Ltd.
EGFR inhibitor BIBU induces apoptosis and defective autophagy in glioma cells
Authors: Ghildiyal Ruchi , Dixit Deobrat , Sen Ellora 
Published: June 2012

AbstractThe importance of aberrant EGFR signaling in glioblastoma progression and the promise of EGFR‐specific therapies, prompted us to determine the efficacy of novel EGFR inhibitor BIBU‐1361 [(3‐chloro‐4‐fluoro‐phenyl)‐[6‐(4‐diethylaminomethyl‐piperidin‐1‐yl)‐pyrimido [5,4‐d]pyrimidin‐4‐yl]‐amine] in affecting glioma survival. BIBU induced apoptosis in a caspase‐dependent manner and induced cell cycle arrest in glioma cells. Apoptosis was accompanied by decreased EGFR levels and its increased distribution towards caveolin rich lipid raft microdomains. BIBU inhibited pro‐survival pathways Akt/mTOR and gp130/JAK/STAT3; and decreased levels of pro‐inflammatory cytokine IL‐6. BIBU caused increased LC3‐I to LC3‐II conversion and triggered the internalization of EGFR within vacuoles along with its increased co‐localization with LC3‐II. BIBU caused accumulation of p62 and increased levels of cleaved forms of Beclin‐1 in all the cell lines tested. Importantly, BIBU failed to initiate execution of autophagy as pharmacological inhibition of autophagy with 3‐Methyladenine or Bafilomycin failed to rescue BIBU mediated death. The ability of BIBU to abrogate Akt and STAT3 activation, induce apoptosis and prevent execution of autophagy warrants its investigation as a potent anti‐glioma target. © 2012 Wiley Periodicals, Inc.
Free Radical Scavenging Activities of Polyphenolic Compounds Isolated from Medicago sativa and Medicago truncatula Assessed by Means of Thin‐layer Chromatography DPPH˙ Rapid Test
Authors: Cieśla Łukasz , Kowalska Iwona , Oleszek Wiesław , Stochmal Anna 
Published: June 2012

ABSTRACTIntroductionThe structure of polyphenolic compounds influences their anti‐oxidant potential. Finding a simple, rapid and reliable analytical method to study the structure–activity relationships for numerous samples is challenging.ObjectiveTo develop a simple thin‐layer chromotography–2,2‐diphenyl‐1‐picrylhdrazyl (TLC–DPPH˙) protocol with image processing to study the influence of the structure of polyphenols on observed direct anti‐oxidant properties.MethodologyFirst, compounds exhibiting free radical scavenging activities were chosen from among the isolated compounds with the application of a rapid TLC dot‐blot test. The active ones were further chromatographed on silica gel plates using the mobile phase: acetonitrile:water:chloroform:formic acid (60:15:10:5, v/v/v/v). Subsequently the plates were stained with DPPH˙ methanolic solution. An improved image processing protocol was used to quantitatively measure the polyphenols’ activity.ResultsThe application of a properly optimised chromatographic system enabled separation of the investigated compounds from dimethyl sulphoxide (DMSO) that influences the results of an anti‐oxidant test. New solutions enabling better data processing are proposed. It has been discovered that acylation of flavonoid glycosides with hydroxycinnamic acids increases their direct anti‐oxidant properties. Some of the analysed glycosides acylated with ferulic acid molecule were found to be the most potent free radical scavengers from among those analysed. The amount of sugar moieties as well as their type also influenced the observed activity.ConclusionA simple, rapid and reliable TLC–DPPH˙ test with image processing has been developed enabling comparison of free radical scavenging activity of plant polyphenols. The influence of different structural features on the observed activity was measured successfully. Copyright © 2012 John Wiley & Sons, Ltd.
Tyrosinase‐mediated in situ forming hydrogels from biodegradable chondroitin sulfate–tyramine conjugates
Authors: Jin Rong , Lou Bo , Lin Chao 
Published: June 2012

AbstractTyrosinase‐mediated crosslinking of chondroitin sulfate–tyramine (CS‐TA) conjugates was successfully applied in the preparation of biodegradable in situ forming hydrogels under physiological conditions. Depending on the polymer concentration, the degree of substitution of TA residue and the tyrosinase concentration, the gelation times ranged from 2.3 to 129 min. Studies on the gel contents of CS‐TA hydrogels showed that their degrees of crosslinking could be controlled by varying the tyrosinase concentrations. CS‐TA hydrogels could be completely degraded by the chondroitinase ABC within a time range from 6 days to 11 weeks. CS‐TA hydrogels possessed highly elastic properties and their storage moduli varied from 120 to 1300 Pa, as determined by rheological analysis. Scanning electron microscopy observation confirmed that CS‐TA hydrogels contained a well‐interconnected pore structure. A live–dead assay demonstrated that NIH 3T3 fibroblasts incorporated in CS‐TA hydrogels retained their viability. In addition, in vitro release of methylene blue (a photodynamic therapy drug) from CS‐TA hydrogels could be effectively sustained by the drug encapsulation in the hydrogels. This study indicates that tyrosinase‐mediated in situ forming CS‐TA hydrogels are promising for biomedical applications including drug release and tissue engineering. © 2012 Society of Chemical Industry