bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mixture toxicity of wood preservative products in the fish embryo toxicity test
Authors: Coors Anja , Dobrick Jan , Möder Monika , Kehrer Anja 
Published: April 2012

Abstract
Wood preservative products are used globally to protect wood from fungal decay and insects. We investigated the aquatic toxicity of five commercial wood preservative products, the biocidal active substances and some formulation additives contained therein, as well as six generic binary mixtures of the active substances in the fish embryo toxicity test (FET). Median lethal concentrations (LC50) of the single substances, the mixtures, and the products were estimated from concentration–response curves and corrected for concentrations measured in the test medium. The comparison of the experimentally observed mixture toxicity with the toxicity predicted by the concept of concentration addition (CA) showed less than twofold deviation for all binary mixtures of the active substances and for three of the biocidal products. A more than 60-fold underestimation of the toxicity of the fourth product by the CA prediction was detected and could be explained fully by the toxicity of one formulation additive, which had been labeled as a hazardous substance. The reason for the 4.6-fold underestimation of toxicity of the fifth product could not be explained unambiguously. Overall, the FET was found to be a suitable screening tool to verify whether the toxicity of formulated wood preservatives can reliably be predicted by CA. Applied as a quick and simple nonanimal screening test, the FET may support approaches of applying component-based mixture toxicity predictions within the environmental risk assessment of biocidal products, which is required according to European regulations. Environ. Toxicol. Chem. 2012;31:1239–1248. © 2012 SETAC
Runt‐related transcription factor 3 reverses epithelial–mesenchymal transition in hepatocellular carcinoma
Authors: Tanaka Shigetomi , Shiraha Hidenori , Nakanishi Yutaka , Nishina Shin‐Ichi , Matsubara Minoru , Horiguchi Shigeru , Takaoka Nobuyuki , Iwamuro Masaya , Kataoka Junro , Kuwaki Kenji , Hagihara Hiroaki , Toshimori Junichi , Ohnishi Hideki , Takaki Akinobu , Nakamura Shinichiro , Nouso Kazuhiro , Yagi Takahito , Yamamoto Kazuhide 
Published: April 2012

AbstractLoss or decreased expression of runt‐related transcription factor 3 (RUNX3), a tumor suppressor gene involved in gastric and other cancers, has been frequently observed in hepatocellular carcinoma (HCC). The objective of this study was to identify the regulatory mechanism of the epithelial–mesenchymal transition (EMT) by RUNX3 in HCC. Human HCC cell lines, Hep3B, Huh7, HLF and SK‐Hep1, were divided into low‐ and high‐EMT lines, based on their expression of TWIST1 and SNAI2, and were used in this in vitro study. Ectopic RUNX3 expression had an anti‐EMT effect in low‐EMT HCC cell lines characterized by increased E‐cadherin expression and decreased N‐cadherin and vimentin expression. RUNX3 expression has previously been reported to reduce jagged‐1 (JAG1) expression; therefore, JAG1 ligand peptide was used to reinduce EMT in RUNX3‐expressing low‐EMT HCC cells. Immunohistochemical analyses were performed for RUNX3, E‐cadherin, N‐cadherin and TWIST1 in 33 human HCC tissues, also divided into low‐ and high‐EMT HCC, based on TWIST1 expression. E‐cadherin expression was correlated positively and N‐cadherin expression was correlated negatively with RUNX3 expression in low‐EMT HCC tissues. Correlations between EMT markers and RUNX3 mRNA expression were analyzed using Oncomine datasets. Similarly, mRNA expression of E‐cadherin was also significantly correlated with that of RUNX3 in low‐EMT HCC, while mRNA expression of JAG1 was negatively correlated with that of RUNX3. These results suggest a novel mechanism by which loss or decreased expression of RUNX3 induces EMT via induction of JAG1 expression in low‐EMT HCC.
Suppression of signal transducers and activators of transcription 1 in hepatocellular carcinoma is associated with tumor progression
Authors: Hosui Atsushi , Klover Peter , Tatsumi Tomohide , Uemura Akio , Nagano Hiroaki , Doki Yuichiro , Mori Masaki , Hiramatsu Naoki , Kanto Tatsuya , Hennighausen Lothar , Hayashi Norio , Takehara Tetsuo 
Published: April 2012

AbstractSignal transducers and activators of transcription (STAT) 1 plays a pivotal role in cell‐cycle and cell‐fate determination, and vascular endothelial growth factor (VEGF) also contributes tumor growth. Recently, interferon (IFN) α has been reported to be effective for prevention of hepatocellular carcinomas (HCCs) recurrence, but the detailed mechanisms remain elusive. In vitro, cobalt chloride–treated VEGF induction and hypoxia responsive element (HRE) promoter activity were inhibited by IFNs and this abrogation was cancelled by introduction of small interfering RNA for STAT1. Immunoprecipitation/chromatin immunoprecipitation analyses showed STAT1 bound to hypoxia‐inducible factor (HIF)‐1α and dissociated HIF‐complex from HRE promoter lesion. In a xenograft model using Balb/c nude mice, tumor growth was suppressed by IFNα through inhibition of VEGF expression and it was oppositely enhanced when STAT1‐deleted cells were injected. This augmentation was due to upregulation of VEGF and hyaluronan synthase 2. In human samples, 29 HCCs were resected, divided into two groups based on STAT1 activation in tumor and the clinical features were investigated. Patients with suppressed STAT1 activity had a shorter recurrence‐free survival. Histological and reverse transcriptase‐polymerase chain reaction (RT‐PCR) analyses showed portal vein microinvasion and increased VEGF levels in tumors from suppressed STAT1 group. These human samples also showed a reverse correlation between VEGF and STAT1‐regulated genes expression. These results in vitro and in vivo suggested that IFNα are potential candidates for prevention of vessel invasion acting through inhibition of VEGF expression and need to be properly used when STAT1 expression is suppressed.
Dimethylarginine dimethylaminohydrolase 1 regulates nerve growth factor‐promoted differentiation of PC12 cells in a nitric oxide‐dependent but asymmetric dimethylargenine‐independent manner
Authors: Wang Shan , Hu Chang‐Ping , Yuan Qiong , Zhang Wei‐Fang , Zhou Zhi , Nie Sheng‐Dan , Jiang Jun‐Lin , Li Yuan‐Jian 
Published: April 2012

AbstractThere are significant morphological and biochemical alterations during nerve growth factor (NGF)‐promoted neuronal differentiation, and the process is regulated by molecules, including nitric oxide (NO). Dimethylarginine dimethylaminohydrolase (DDAH) is thought to play a critical role in regulating NO production via hydrolyzing the endogenous NO synthase (NOS) inhibitor asymmetric dimethylarginine (ADMA). Thus, we tested the role of DDAH in NGF‐promoted differentiation of PC12 (pheochromocytoma) cells. The present results show that both mRNA and protein levels of DDAH1 were increased, whereas those of DDAH2 were decreased, during NGF‐promoted cell differentiation. Both the DDAH activity and the ADMA level in cultured medium were unchanged in this process. NGF promoted neurite formation and induced the expression of microtubule‐associated protein 2 (MAP2), a neuronal marker, which were both significantly repressed by DDAH1 silence with small interfering RNA but not by DDAH2 silence. The expressions of three isoforms of NOS were markedly upregulated after NGF stimulation with a time course similar to that of DDAH1, which were attenuated by DDAH1 silence. Conversely, overexpression of DDAH1 accelerated neurite formation in PC12 cells, concomitantly with upregulating the expression of three NOS isoforms. In summary, our data reveal the critical regulatory effect of DDAH1 on NGF‐promoted differentiation of PC12 cells in an NOS/NO‐dependent but ADMA‐independent manner. © 2012 Wiley Periodicals, Inc.
Micronized acellular dermal matrix as an efficient expansion substrate and delivery vehicle of adipose‐derived stem cells for vocal fold regeneration
Authors: Liang Qiang , Liu Shiyu , Han Peng , Li Xiaofeng , Li Xiaobing , Zhao Yu , Liang Yuanyuan , Deng Zhihong , Jin Yan 
Published: April 2012

AbstractObjectives/Hypothesis:Cell therapy has been shown to prevent vocal fold scarring and atrophy. However, problems that include the expansion of large numbers of cells in vitro and the poor survival of transplanted cells in vivo must be solved. The aim of this study was to use micronized acellular dermal matrix (MADM) as an expansion substrate of rabbit allogeneic adipose‐derived stem cells (ADSCs) and to apply the combination of the matrix and cells, ADSC‐MADM, to vocal fold regeneration.Study Design:Animal experiment.Methods:The proliferation of ADSCs that were cultured on the MADM was evaluated using 3‐(4,5‐dimethylthizazol‐2‐yl)‐5‐(3‐carboxymethoxy‐phenyl)‐2‐(4‐sulfonyl)‐2H‐tetrazolium, and a rabbit acute vocal fold injury model was established by laser injury. Eighteen New Zealand white rabbits were randomly divided into three groups, which were injected with ADSC‐MADM, ADSCs, and MADM, respectively. Morphological analysis was performed by laryngoscope, and histological analyses were indicated by hematoxylin and eosin staining, van Gieson staining, and immunofluorescence. Additionally, the in vivo survival of the ADSCs was determined by CM‐Dil cell labeling.Results:When compared with a two‐dimensional culture, the MADM significantly promoted proliferation of ADSCs. Morphological and histological analyses indicated that, when compared to only using of MAMD or the nontreatment sample, the use of ADSC‐MADM or only using ADSCs successfully prevent scarring and atrophy. Moreover, ADSC‐MADM exhibited a better therapeutic effect than when only using ADSCs, which was probably due to the MADM significantly enhancing the survival of transplanted ADSCs.Conclusions:MADM could be used as an efficient expansion substrate and delivery vehicle for ADSCs in vocal fold regeneration. Laryngoscope, 2012
Thermal Properties and Degradation Behavior of Linear and Branched Poly(L‐lactide)s and Poly(L‐lactide‐co‐glycolide)s
Authors: Atkinson Jeffrey L. , Vyazovkin Sergey 
Published: April 2012

AbstractPoly(lactide)s and poly(lactide‐co‐glycolide)s with different number of arms are synthesized from L‐lactide and glycolide monomers using stannous(II) 2‐ethylhexanoate and alcohols containing 1, 2, 25, and 51 hydroxyl groups. 1‐dodecanol is used to produce the 1‐arm polymer, poly(ethylene glycol) for the 2‐arm polymer, and polyglycidols of appropriate molecular weight are used to initiate the 25‐ and 51‐arm branched polyesters. The polymers are characterized by 1H NMR and GPC. The thermal properties of the polymers are studied using DSC. Their degradation behavior is indestigated using a combination of thermogravimetry, FTIR spectroscopy, and isoconversional kinetic analysis.
Absence of changes in GABA concentrations with age and gender in the human anterior cingulate cortex: A MEGA‐PRESS study with symmetric editing pulse frequencies for macromolecule suppression
Authors: Aufhaus E. , Weber‐Fahr W. , Sack M. , Tunc‐Skarka N. , Oberthuer G. , Hoerst M. , Meyer‐Lindenberg A. , Boettcher U. , Ende G. 
Published: April 2012

AbstractDespite MEGA‐PRESS being a robust method for editing the GABA resonance, there are macromolecule resonances at the same chemical shift that are coedited with this sequence. Although this is a known problem, it is still often overlooked. We aimed to evaluate the amount of macromolecule signal coedited, as well as the gender and age dependencies for the GABA resonance at 3.01 ppm using MEGA‐PRESS with two different editing pulse frequencies. Forty‐five healthy subjects (21–52 years) were included in an in vivo single voxel MEGA‐PRESS study at 3.0 T. Phantom measurements were conducted to measure the signal loss when switching the editing pulse between 1.5 and 1.9 ppm instead of the mostly used switching between 1.9 and 7.5 ppm. The in vivo GABA signal detected by switching the editing pulse frequencies between 1.5 and 1.9 ppm was only 50% of the mean GABA detected by switching the editing pulse frequencies between 1.9 and 7.5 ppm. No gender differences were detected. A small age dependency was observed for GABA plus macromolecules, but not for GABA, suggesting an age‐dependent macromolecule increase. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Influence of the hard segment content on the mechanical and tribological properties of the polyurethane modified by hydroxyl‐terminated polydimethylsiloxane under different lubricated conditions
Authors: Wang Tingmei , Zhao Gai , Wang Qihua 
Published: April 2012

AbstractTwo kinds of polyurethane (PU) composites with different hard segment content modified by a high molecular weight hydroxyl‐terminated polydimethylsiloxane (HTPDMS) were prepared. The effect of the hard segment content on the mechanical and tribological properties of the PU composites was studied. Tensile strength of the PU composites increased with the increasing of the hard segment content. The friction and wear experiments were tested on a MRH‐3 model ring‐on‐block test rig at different sliding speeds and loads under different lubricated conditions. Experimental results revealed that the coefficient of friction (COF) and the wear rate value of the PU composites decreased with increasing hard segment content and the COF of the PU composites under dry friction was higher than that under water and sea water lubrication. Scanning electron microscopy (SEM) investigations showed that the worn surfaces of the PU under water and sea water lubrication were smoother than that under dry friction. Besides, the wear rate value of the PU composites under water and sea water lubrication was smaller than that under dry friction. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Reaction kinetics of nonideal hyperbranched polymerizations: Influences of chain rigidity and reaction reversibility
Authors: Wang Long , He Xuehao 
Published: April 2012

AbstractTo deeply understand the dependence of hyperbranched polymerization on the specialties of molecular chain and chemical reaction, the reaction kinetics of nonideal hyperbranched polymerizations considering the chain rigidity and reaction reversibility are studied using the reactive three‐dimensional bond fluctuation lattice model. It is found that, with the increase of chain rigidity, the formation probability of intramolecular rings decreases and less intramolecular rings with larger size are formed. It results in the increase of the degrees of polymerization and polydispersity index with the rise of chain rigidity at higher conversion. Furthermore, our simulation shows that the reversibility of reaction has strong influences on the equilibrium state and kinetic process of hyperbranched polymerizations. When the ratio of reverse reaction probability to forward reaction probability is larger, the conversion and degrees of polymerization quickly grow to the equilibrium value simultaneously. At smaller reverse reaction probability, however, the weigh‐average degree of polymerization and polydispersity index further increase slowly after approaching the equilibrium conversion. Our results are well‐consistent with the experiments to indicate that the introduction of the specialties of macromolecule and chemical reaction are necessary for quantitative analysis of the realistic hyperbranched polymerizations. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Teflon hierarchical nanopillars with dry and wet adhesive properties
Authors: Izadi Hadi , Zhao Boxin , Han Yougun , McManus Neil , Penlidis Alexander 
Published: April 2012

AbstractThe superior material properties of β‐keratin along with the hierarchical high‐aspect‐ratio structure of geckos' foot pad have enabled geckos to stick readily and rapidly to almost any surfaces in both dry and wet conditions. In this research, nonsticky fluoropolymer (Teflon AF) resembling β‐keratin rigidity and having an extremely low surface energy and dielectric constant was applied to fabricate a novel dry adhesive consisting of high‐aspect‐ratio nanopillars terminated with a “fluffy” top layer. Both the nanopillars and the terminating layer are fabricated concurrently by replica molding using a nanoporous anodic aluminum oxide membrane as the mold. These Teflon AF hierarchical nanostructures are shown to have an exceptional capacity to generate strong adhesion in both dry conditions and under water because of combined actions of van der Waals forces, electrostatic attractions, and hydrophobic effects. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Data‐based mechanistic modelling of tidally affected river reaches for flood warning purposes: an example on the River Dee, UK
Authors: Smith P. J. , Beven K. J. , Horsburgh K. 
Published: April 2012

AbstractThis article discusses a coupled water level forecasting system constructed for the River Dee (UK) using parsimonious, physically interpretable, time series models. Tidal forecasts, provided by a simple harmonic model, and observed water levels at the upstream boundary are used to drive a nonlinear hydrological model which forecasts water levels at three gauged sites on the flood plain. The assimilation of observed data and use of the model for real‐time forecasting is presented. The results generated indicate that the forecasts of river water can be both timely and accurate except close to the tidal boundary where the the tide is affected by the weir at Chester. Copyright © 2012 Royal Meteorological Society
Terrain classification and identification of tree stems using ground‐based LiDAR
Authors: McDaniel Matthew W. , Nishihata Takayuki , Brooks Christopher A. , Salesses Phil , Iagnemma Karl 
Published: April 2012

AbstractTo operate autonomously in forested terrain, unmanned ground vehicles must be able to identify the load‐bearing surface of the terrain (i.e., the ground) and obstacles in the environment. To travel long distances, they must be able to track their position even when the forest canopy obstructs GPS signals, e.g., by tracking progress relative to tree stems. This paper presents a novel, robust approach for modeling the ground plane and tree stems in forests from a single viewpoint using a lightweight LiDAR scanner. Ground plane identification is implemented using a two‐stage approach. The first stage, a local height‐based filter, discards most nonground points. The second stage, based on a support vector machine classifier, identifies which of the remaining points belong to the ground. Main tree stems are modeled as cylinders or cones to estimate the diameter 130 cm above the ground plane. To fit these models, candidate main stem data are selected by finding points approximately 130 cm above the ground. These points are clustered into separate point clouds for each stem. Cylinders and cones are fit to each point cloud, and heuristic filters identify which fits correspond to tree stems. Experimental results from five forested environments demonstrate the effectiveness of this approach. For ground plane estimation, the overall classification accuracy was 86.28% with a mean error for the ground height of approximately 4.7 cm. For stem estimation, up to 50% of the main stems were accurately modeled using cones, with a root mean square diameter error of 13.2 cm.© 2012 Wiley Periodicals, Inc.
1400 years of extreme precipitation patterns over the Mediterranean French Alps and possible forcing mechanisms
Authors: Wilhelm Bruno , Arnaud Fabien , Sabatier Pierre , Crouzet Christian , Brisset Elodie , Chaumillon Eric , Disnar Jean-Robert , Guiter Frederic , Malet Emmanuel , Reyss Jean-Louis , Tachikawa Kazuyo , Bard Edouard , Delannoy Jean-Jacques 
Published: April 2012

AbstractInvestigation of Lake Allos sediments revealed ~ 160 graded layers, interpreted as flood deposits, over the last 1400 yr. Comparisons with records of historic floods support the interpretation of flood deposits and suggest that most recorded flood events are the result of intense meso-scale precipitation events. As there is no evidence for any major changes in erosion processes in the catchment since the Medieval Warm Period (MWP), we interpret the Allos record in terms of repeated intense precipitation events over the last millennium, with a low flood frequency during the MWP and more frequent and more intense events during the Little Ice Age. This interpretation is consistent with the pattern of increasingly humid conditions in the northwestern Mediterranean region. This long-term trend is superimposed on high frequency oscillations that correlate with solar activity and autumnal North Atlantic Oscillation (NAO). Finally, a comparison of flood records across the northwestern Mediterranean region showed that intense precipitation events in Allos (east of the Rhône Valley) were out of phase with events in the Cévennes (west of the Rhône) but in phase with events in eastern Spain. Supported by meteorological analyses, this suggests an oscillation in atmospheric circulation patterns over the northwestern Mediterranean.
First- and second-order forcing expansions in a lattice Boltzmann method reproducing isothermal hydrodynamics in artificial compressibility form
Authors: Silva Goncalo , Semiao Viriato 
Published: April 2012

AbstractThe isothermal Navier–Stokes equations are determined by the leading three velocity moments of the lattice Boltzmann method (LBM). Necessary conditions establishing the hydrodynamic consistency of these moments are provided by multiscale asymptotic techniques, such as the second-order Chapman–Enskog expansion. However, for simulating incompressible hydrodynamics the structure of the forcing term in the LBM is still a discordant issue as far as its correct velocity expansion order is concerned. This work uses the traditional second-order Chapman–Enskog expansion analysis to demonstrate that the truncation order of the forcing term may depend on the time regime in this case. This is due to the fact that LBM does not reproduce exactly the incompressibility condition. It rather approximates it through a weakly compressible or an artificial compressible system. The present study shows that for the artificial compressible setup, as the incompressibility flow condition is singularly perturbed by the time variable, such a connection will also affect the LBM forcing formulation. As a result, for time-independent incompressible flows the LBM forcing must be truncated to first order whereas for a time-dependent case it is convenient to include the second-order term. The theoretical findings are confirmed by numerical tests carried out in several distinct benchmark flows driven by space- and/or time-varying body forces and possessing known analytical solutions. These results are verified for the single relaxation time, the multiple relaxation time and the regularized collision models.