bluuebunny/crossref_metadata_2025 huggingface dataset:
Surfactant-facilitated remediation of metal-contaminated soils: Efficacy and toxicological consequences to earthworms
Authors: Slizovskiy Ilya B , Kelsey Jason W , Hatzinger Paul B
Published: September 2010

The effectiveness of surfactant formulations to remove aged metals from a field soil and their influence on soil toxicity was investigated. Batch studies were conducted to evaluate the efficacy of cationic (1-dodecylpyridinium chloride; DPC), nonionic (oleyl dimethyl benzyl ammonium chloride; trade name Ammonyx KP), and anionic (rhamnolipid biosurfactant blend; trade name JBR-425) surfactants for extracting Zn, Cu, Pb, and Cd from a soil subjected to more than 80 years of metal deposition. All three surfactants enhanced removal of the target metals. The anionic biosurfactant JBR-425 was most effective, reducing Zn, Cu, Pb, and Cd in the soil by 39, 56, 68, and 43%, respectively, compared with less than 6% removal by water alone. Progressive acidification of the surfactants with citric acid buffer or addition of ethylenediaminetetra-acetic acid (EDTA) further improved extraction efficiency, with more than 95% extraction of all four metals by surfactants acidified to pH 3.6 and generally greater than 90% removal of all metals with addition of 0.1 M EDTA. In two species of earthworm, Eisenia fetida and Lumbricus terrestris, metal bioaccumulation was reduced by approximately 30 to 80%, total biomass was enhanced by approximately threefold to sixfold, and survival was increased to greater than 75% in surfactant-remediated soil compared with untreated soil. The data indicate that surfactant washing may be a feasible approach to treat surface soils contaminated with a variety of metals, even if those metals have been present for nearly a century, and that the toxicity and potential for metal accumulation in biota from the treated soils may be significantly reduced. Environ. Toxicol. Chem. 2011;30:112–123. © 2010 SETAC
Physiological effects of temperature and a herbicide mixture on the soft-shell clam Mya arenaria (Mollusca, Bivalvia)
Authors: Greco Luna , Pellerin Jocelyne , Capri Ettore , Garnerot Florent , Louis Séverine , Fournier Michel , Sacchi Angela , Fusi Marco , Lapointe Dominique , Couture Patrice
Published: September 2010

The aim of the current study was to investigate effects of temperature and a mixture of herbicides on the physiological status of the bivalve Mya arenaria. Bivalves acclimated to two temperatures (7 and 18°C) were exposed for 28 d to 0.01 mg/L of a pesticide formulation containing dichlorophenoxyacetic acid (2,4-D), 2-(2-methyl-4-chlorophenoxy) propionic acid (mecoprop), and 3,6-dichloro-2-methoxybenzoic acid (dicamba). At days 7, 14, and 28, mortality, immune parameters (hemocyte number, phagocytic activity, and efficiency), biomarkers of oxidative stress (catalase [CAT] and superoxide dismutase [SOD] activities and malondialdehyde [MDA] content), the metabolic enzyme cytochrome C oxidase (CCO), a biomarker of pesticide exposure (acetylcholinesterase [AChE]), and the activity of an enzyme related to gametogenesis (aspartate transcarbamylase [ATCase]) were monitored in clam tissues. Gonadosomatic index (GSI), condition factor (CF), and sex were also assessed. In clams acclimated to 7°C, exposure to pesticide enhanced CCO activity and CF and decreased MDA content, hemocyte number, CAT, and SOD activities. In clams kept at 18°C, pesticide effects appeared minor compared with samples kept at 7°C. In bivalves acclimated to 18°C, CCO, SOD, and ATCase activity and MDA content were enhanced, and hemocyte number, CAT, and AchE activities and phagocytosis were suppressed. In samples exposed to pesticides, increased temperature enhanced MDA content and CCO and SOD activity and suppressed hemocyte number and CAT and AchE activity. A gradual sexual maturation was observed in both sexes through experimental time, but females had a higher sensitivity to temperature and pesticides compared to males. Increased temperature altered the ability of the sentinel species Mya arenaria to respond to pesticide exposures. Further work is needed to understand the impacts of increasing temperature on the whole St. Lawrence estuary ecosystem. Environ. Toxicol. Chem. 2011;30:132–141. © 2010 SETAC
Plants growing on contaminated and brownfield sites appropriate for use in Organisation for Economic Co-operation and Development terrestrial plant growth test
Authors: Sinnett Danielle E , Lawrence Victoria K , Hutchings Tony R , Hodson Mark E
Published: September 2010

The Organisation for Economic Co-operation and Development (OECD) terrestrial plant test is often used for the ecological risk assessment of contaminated land. However, its origins in plant protection product testing mean that the species recommended in the OECD guidelines are unlikely to occur on contaminated land. Six alternative species were tested on contaminated soils from a former Zn smelter and a metal fragmentizer with elevated concentrations of Cd, Cu, Pb, and Zn. The response of the alternative species was compared with that of two species recommended by the OECD: Lolium perenne (perennial ryegrass) and Trifolium pratense (red clover). Urtica dioica (stinging nettle) and Poa annua (annual meadowgrass) had low emergence rates in the control soil and so may be considered unsuitable. Festuca rubra (Chewings fescue), Holcus lanatus (Yorkshire fog), Senecio vulgaris (common groundsel), and Verbascum thapsus (great mullein) offer good alternatives to the OECD species. In particular, H. lanatus and S. vulgaris were more sensitive to the soils with moderate concentrations of Cd, Cu, Pb, and Zn than the OECD species. Environ. Toxicol. Chem. 2011;30:124–131. © 2010 SETAC
An assessment of honeybee colony matrices, Apis mellifera (Hymenoptera: Apidae) to monitor pesticide presence in continental France
Authors: Chauzat Marie-Pierre , Martel Anne-Claire , Cougoule Nicolas , Porta Philippe , Lachaize Julie , Zeggane Sarah , Aubert Michel , Carpentier Patrice , Faucon Jean-Paul
Published: September 2010

The frequency of occurrence and relative concentration of 44 pesticides in apicultural (Apis mellifera) matrices collected from five French locations (24 apiaries) were assessed from 2002 to 2005. The number and nature of the pesticides investigated varied with the matrices examined—living honeybees, pollen loads, honey, and beeswax. Pollen loads and beeswax had the highest frequency of pesticide occurrence among the apiary matrices examined in the present study, whereas honey samples had the lowest. The imidacloprid group and the fipronil group were detected in sufficient amounts in all matrices to allow statistical comparisons. Some seasonal variation was shown when residues were identified in pollen loads. Given the results (highest frequency of presence) and practical aspects (easy to collect; matrix with no turnover, unlike with bees that are naturally renewed), pollen loads were the best matrix for assessing the presence of pesticide residues in the environment in our given conditions. Environ. Toxicol. Chem. 2011;30:103–111. © 2010 SETAC
Fast predicted handover in IEEE 802.16 networks
Authors: Becvar Zdenek , Mach Pavel
Published: September 2010

The handover procedure can have a negative impact on the quality of service due to the short break in the connection. This paper proposes a modification of the hard handover procedure to enable reduction of the handover interruption time by exploiting the results of a handover prediction. The prediction of handover allows performing a part of handover procedure in advance to the interruption of a connection caused by the handover. The simulation results show that the proposed handover procedure fulfils requirements on the handover interruption according to the originating IEEE 802.16m standard for a wide range of frame durations. Moreover, the proposed technique outperforms conventional handover and all well‐known proposals shortening the handover interruption as well. Copyright © 2010 John Wiley & Sons, Ltd.
Evolution of Inflammation in Nonalcoholic Fatty Liver Disease: The Multiple Parallel Hits Hypothesis
Authors: Tilg Herbert , Moschen Alexander R.
Published: September 2010

Whereas in most cases a fatty liver remains free of inflammation, 10%-20% of patients who have fatty liver develop inflammation and fibrosis (nonalcoholic steatohepatitis [NASH]). Inflammation may precede steatosis in certain instances. Therefore, NASH could reflect a disease where inflammation is followed by steatosis. In contrast, NASH subsequent to simple steatosis may be the consequence of a failure of antilipotoxic protection. In both situations, many parallel hits derived from the gut and/or the adipose tissue may promote liver inflammation. Endoplasmic reticulum stress and related signaling networks, (adipo)cytokines, and innate immunity are emerging as central pathways that regulate key features of NASH. (Hepatology 2010;52:1836-1846)
CD8+Foxp3+ tumor infiltrating lymphocytes accumulate in the context of an effective anti‐tumor response
Authors: Le Dung T. , Ladle Brian H. , Lee Timothy , Weiss Vivian , Yao Xiaosai , Leubner Ashley , Armstrong Todd D. , Jaffee Elizabeth M.
Published: September 2010

The composition of tumor infiltrating lymphocytes (TIL) is heterogeneous. In addition, the ratio of various subpopulations in the tumor microenvironment is highly dependent on the nature of the host's immune response. Here, we characterize Foxp3‐expressing CD8+ T cells in the tumor that demonstrate effector function and accumulate in the context of an effective anti‐tumor response. CD8+Foxp3+ T cells are induced in TIL in regressing tumors of FVB/N mice treated with a GM‐CSF secreting HER‐2/neu targeted whole cell vaccine. Foxp3 expression in tumor antigen‐specific CD8 T cells is restricted to the tumor microenvironment and influenced by cues in the tumor. Interestingly, Foxp3+ and Foxp3− CD8+ T cells have similar IFN‐γ production and antigen‐specific degranulation after stimulation with RNEU420–429, the immunodominant HER‐2/neu (neu) epitope in this model. Adoptive transfer studies, using RNEU(420–429)‐specific effector T cells into neu‐N mice (a model that results in immune tolerance to neu), confirm that CD8+Foxp3+ T cells are present in tumors only if there is an existing pool of tumor‐rejecting effector T cells. CD8+Foxp3+ TILs mark the presence of tumor‐rejecting antigen‐specific T cells and their accumulation serves as a marker for an effective T cell response.
Use of GC × GC/TOF‐MS and LC/TOF‐MS for metabolomic analysis of Hyalella azteca chronically exposed to atrazine and its primary metabolite, desethylatrazine
Authors: Ralston‐Hooper Kimberly J. , Adamec Jiri , Jannash Amber , Mollenhauer Robert , Ochoa‐Acuña Hugo , Sepúlveda Maria S.
Published: September 2010

Atrazine is one of the most commonly detected contaminants in the U.S. Little information is available on one of atrazine's metabolites, desethylatrazine (DEA). Two‐dimensional gas chromatography and liquid chromatography coupled with time of flight‐ mass spectrometry were used to examine metabolite profiles of Hyalella azteca chronically exposed to 30 µg/L atrazine and DEA. The majority of identified metabolites were by‐products of β‐oxidation of fatty acids suggesting possible disruption in energy metabolism. Eicosanoids increased in exposed females suggesting possible perturbations in neuropeptide hormonal systems. Overall, this research demonstrates the feasibility of utilizing metabolomic profiling of invertebrate species exposed to environmental contaminants as a way to determine mechanisms of toxicity. Copyright © 2010 John Wiley & Sons, Ltd.
Relationships of lipocalin 2 with breast tumorigenesis and metastasis
Authors: Leng Xiaohong , Wu Yun , Arlinghaus Ralph B.
Published: September 2010

Breast cancer is one of the most common cancers in women worldwide and accounts for one‐sixth of cancer deaths in the United States. Breast cancer consists of a heterogeneous group of tumours classified into five types, in which the HER2/neu positive and the basal type (most are ER and HER2 negative) have the worst clinical prognosis. In recent years, prognostic/predictive markers such as ER/PR or HER2/neu have been widely used in the selection of the optimal breast cancer treatments for individual patients, which have been proven to be very effective in disease control. These results suggest that further examination of the molecular mechanisms underlying the breast tumorigenesis and identification of the potential biomarkers in different types of breast cancers will greatly benefit clinical diagnosis and facilitate the design of more effective personalized therapies to increase patient survival. This review aims to summarize recent research findings on lipocalin 2 (LCN2), a newly identified biomarker and a potential therapeutic target for breast cancer, and the possible mechanisms underlying its role in tumorigenesis and metastasis. J. Cell. Physiol. 226: 309–314, 2011. © 2010 Wiley‐Liss, Inc.
Stromal stem cells from adipose tissue and bone marrow of age‐matched female donors display distinct immunophenotypic profiles
Authors: Pachón‐Peña G. , Yu G. , Tucker A. , Wu X. , Vendrell J. , Bunnell B.A. , Gimble J.M.
Published: September 2010

Adipose tissue is composed of lipid‐filled mature adipocytes and a heterogeneous stromal vascular fraction (SVF) population of cells. Similarly, the bone marrow (BM) is composed of multiple cell types including adipocytes, hematopoietic, osteoprogenitor, and stromal cells necessary to support hematopoiesis. Both adipose and BM contain a population of mesenchymal stromal/stem cells with the potential to differentiate into multiple lineages, including adipogenic, chondrogenic, and osteogenic cells, depending on the culture conditions. In this study we have shown that human adipose‐derived stem cells (ASCs) and bone marrow mesenchymal stem cells (BMSCs) populations display a common expression profile for many surface antigens, including CD29, CD49c, CD147, CD166, and HLA‐abc. Nevertheless, significant differences were noted in the expression of CD34 and its related protein, PODXL, CD36, CD 49f, CD106, and CD146. Furthermore, ASCs displayed more pronounced adipogenic differentiation capability relative to BMSC based on Oil Red staining (7‐fold vs. 2.85‐fold induction). In contrast, no difference between the stem cell types was detected for osteogenic differentiation based on Alizarin Red staining. Analysis by RT‐PCR demonstrated that both the ASC and BMSC differentiated adipocytes and osteoblast displayed a significant upregulation of lineage‐specific mRNAs relative to the undifferentiated cell populations; no significant differences in fold mRNA induction was noted between ASCs and BMSCs. In conclusion, these results demonstrate human ASCs and BMSCs display distinct immunophenotypes based on surface positivity and expression intensity as well as differences in adipogenic differentiation. The findings support the use of both human ASCs and BMSCs for clinical regenerative medicine. J. Cell. Physiol. 226: 843–851, 2011. © 2010 Wiley‐Liss, Inc.
Assembly of the fluorescent acrosomal matrix and its fate in fertilization in the water strider, Aquarius remigis
Authors: Miyata Haruhiko , Noda Naoki , Fairbairn Daphne J. , Oldenbourg Rudolf , Cardullo Richard A.
Published: September 2010

Animal sperm show remarkable diversity in both morphology and molecular composition. Here we provide the first report of intense intrinsic fluorescence in an animal sperm. The sperm from a semi‐aquatic insect, the water strider, Aquarius remigis, contains an intrinsically fluorescent molecule with properties consistent with those of flavin adenine dinucleotide (FAD), which appears first in the acrosomal vesicle of round spermatids and persists in the acrosome throughout spermiogenesis. Fluorescence recovery after photobleaching reveals that the fluorescent molecule exhibits unrestricted mobility in the acrosomal vesicle of round spermatids but is completely immobile in the acrosome of mature sperm. Fluorescence polarization microscopy shows a net alignment of the fluorescent molecules in the acrosome of the mature sperm but not in the acrosomal vesicle of round spermatids. These results suggest that acrosomal molecules are rearranged in the elongating acrosome and FAD is incorporated into the acrosomal matrix during its formation. Further, we followed the fate of the acrosomal matrix in fertilization utilizing the intrinsic fluorescence. The fluorescent acrosomal matrix was observed inside the fertilized egg and remained structurally intact even after gastrulation started. This observation suggests that FAD is not released from the acrosomal matrix during the fertilization process or early development and supports an idea that FAD is involved in the formation of the acrosomal matrix. The intrinsic fluorescence of the A. remigis acrosome will be a useful marker for following spermatogenesis and fertilization. J. Cell. Physiol. 226: 999–1006, 2011. © 2010 Wiley‐Liss, Inc.
PP2A interaction with Rb2/p130 mediates translocation of Rb2/p130 into the nucleus in all‐Trans retinoic acid‐treated ovarian carcinoma cells
Authors: Purev Enkhtsetseg , Soprano Dianne R. , Soprano Kenneth J.
Published: September 2010

One of the mechanisms by which all‐trans retinoic acid (ATRA) has been shown to suppress the growth of CAOV3 ovarian carcinoma cells involves an increase in the accumulation of Rb2/p130 protein, a member of the retinoblastoma family of tumor suppressors. This increase in accumulation of RB2/p130 by ATRA results from increased stability of Rb2/p130 protein as a result of an increase in dephosphorylation of the protein by the serine/threonine phosphatase PP2A. We show that upon ATRA treatment, PP2A interacts with the Rb2/p130 C‐terminus and specifically dephosphorylates two residues (S1080 and T1097) adjacent to NLS1 and NLS2 of Rb2/p130. Moreover, co‐immunoprecipitation studies reveal that Rb2/p130 can form a complex with the nuclear transport proteins, importin α and importin β, binding to the same dephosphorylated NLS1 and NLS2 sites. Finally, mutation of S1080 and T1097 results in retension of Rb2/p130 in the cytoplasm. Our studies suggest that one mechanism by which ATRA treatment of CAOV3 cells induces G0/G1 arrest involves the recruitment of PP2A to the C‐terminus of Rb2/p130, resulting in the dephosphorylation of the S1080 and T1097 adjacent to the NLS and the subsequent interaction of Rb2/p130 with importins leading to transport of the Rb2/p130 to the nucleus where it inhibits cell‐cycle progression. J. Cell. Physiol. 226: 1027–1034, 2011. © 2010 Wiley‐Liss, Inc.
Electrode‐assisted desorption electrospray ionization mass spectrometry
Authors: Özdemir Abdil , Chen Chung‐Hsuan
Published: September 2010

A new ion source has been developed for rapid, noncontact analysis of materials at ambient conditions. The method provides desorption of analytes under ambient conditions directly from different surfaces with little or no sample preparation. The new method, termed electrode‐assisted desorption electrospray ionization (EADESI), is on the basis of the ionization of molecules on different surfaces by highly charged droplets produced on a sharp‐edged high voltage tip, and ions produced are introduced into the mass spectrometer through a capillary. The EADESI technique can be applied to various samples including amino acids, peptides, proteins, drugs and human fluids such as urine and blood. EADESI is promising for routine analyses in different fields such as forensic, environmental and material sciences. EADESI interface can be fit to a conventional ion‐trap mass spectrometer. It can be used for various types of samples with a broad mass range. EADESI can also provide real‐time analysis which is very valuable for biomedical applications. Copyright © 2010 John Wiley & Sons, Ltd.
Hypoxic‐ischemic brain injury exacerbates neuronal apoptosis and precipitates spontaneous seizures in glucose transporter isoform 3 heterozygous null mice
Authors: Fung Camille , Evans Edward , Shin Don , Shin Bo‐Chul , Zhao Yuanzi , Sankar Raman , Chaudhuri Gautam , Devaskar Sherin U.
Published: September 2010

We examined the effects of 45‐min hypoxia (FiO2 0.08; Hx) vs. normoxia (FiO2 0.21; Nx) on the ipsilateral (Ipsi) and contralateral (Ctrl) sides of the brain in neuronal glucose transporter isoform 3 (Glut3) heterozygous null mice (glut3+/−) and their wild‐type littermates (WT), undergoing unilateral carotid artery ligation. Glut3+/− mice, under Nx, demonstrated a compensatory increase in blood–brain barrier/glial Glut1 protein concentration and a concomitant increase in neuronal nitric oxide synthase (nNOS) enzyme activity and Bax protein, with a decrease in procaspase 3 protein (P < 0.05 each). After Hx, reoxygenation in FiO2 of 0.21 led to no comparable adaptive up‐regulation of the ipsilateral brain Glut3 or Glut1 protein at 4 hr and Glut1 at 24 hr in glut3+/− vs. WT. These brain Glut changes in glut3+/− but not WT mice were associated with an increase in proapoptotic Bax protein and caspase‐3 enzyme activity (P < 0.01 each) and a decline in the antiapoptotic Bcl‐2 and procaspase‐3 proteins (P < 0.05 each). Glut3+/− mice after Hx demonstrated TUNEL‐positive neurons with nuclear pyknosis in most ipsilateral (hypoxic‐ischemia) brain regions. A subset (∼55%) of glut3+/− mice developed spontaneous seizures after hypoxic‐ischemia, confirmed by electroencephalography, but the WT mice remained seizure‐free. Pentylenetetrazole testing demonstrated an increased occurrence of longer lasting clinical seizures at a lower threshold in glut3+/− vs. WT mice, with no detectable differences in monamine neurotransmitters. We conclude that hypoxic‐ischemic brain injury in glut3+/− mice exacerbates cellular apoptosis and necrosis and precipitates spontaneous seizures. © 2010 Wiley‐Liss, Inc.
Barrier Properties of Gastrointestinal Mucus to Nanoparticle Transport
Authors: Crater Jason S. , Carrier Rebecca L.
Published: September 2010

Gastrointestinal mucus, a complex network of highly branched glycoproteins and macromolecules, is the first barrier through which orally delivered drug and gene vectors must traverse. The diffusion of such vectors can be restricted by the high adhesivity and viscoelasticity of mucus. In this investigation, the barrier properties of gastrointestinal mucus to particle transport were explored using real‐time multiple particle tracking. The influence of surface chemistry on particle transport rates was examined using amine‐, carboxylate‐, and sulfate‐modified polystyrene nanoparticles. A strong dependence of particle mobility in gastrointestinal mucus on surface charge was observed, with anionic particles diffusing 20–30 times faster than cationic particles. Comparison of diffusion coefficients calculated for gastrointestinal mucus with significantly varying values previously reported in the literature for other mucus sources, including cervicovaginal mucus and cystic fibrosis sputum, highlight the dependence of mucus barrier properties on the anatomical source. A significant degree of transport rate heterogeneity was also observed in native gastrointestinal mucus, suggesting a highly heterogeneous distribution of pore sizes. Furthermore, the suitability of purified mucin as a model system for transport studies was assessed by comparing particle transport rates between native intestinal mucus and purified porcine gastric mucin. Particle transport rates were approximately threefold lower in native mucus compared to purified mucin for anionic particles, yet comparable for cationic particles. Differences between barrier properties of the purified mucin preparation and native mucus depended on specific carrier properties, indicating that the purified mucin preparation does not provide an accurate model system for native mucus.

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Construction of an Artificial Glutathione Peroxidase Active Site on Copolymer Vesicles
Authors: Yin Yanzhen , Huang Xin , Lv Chunyan , Wang Liang , Yu Shuangjiang , Luo Quan , Xu Jiayun , Liu Junqiu
Published: September 2010

To construct an efficient GPx mimic, a novel method for preparing polymer‐based vesicles carrying GPx‐active sites was developed. A series of block copolymers loaded with recognition and catalytic sites were synthesized based on polystyrene‐block‐poly[tri(ethylene glycol) methyl ether acrylate]s (PS‐PMEO3MAs). By altering the molar ratio of the functional copolymers, vesicles with GPx activity were obtained by self‐assembly of these functional copolymers through blending. The optimum GPx mimic constructed by the blending process exhibited high catalytic activity and acted as a real catalyst with typical saturation kinetics behavior. The method may be of benefit for designing other enzyme mimics and may cast a light on constructing other biologically related functional nanoparticles.

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Bioactive Scaffolds for Engineering Vascularized Cardiac Tissues
Authors: Chiu Loraine L. Y. , Radisic Milica , Vunjak‐Novakovic Gordana
Published: September 2010

Functional vascularization is a key requirement for the development and function of most tissues, and most critically cardiac muscle. Rapid and irreversible loss of cardiomyocytes during cardiac infarction directly results from the lack of blood supply. Contractile cardiac grafts, engineered using cardiovascular cells in conjunction with biomaterial scaffolds, are an actively studied method for cardiac repair. In this article, we focus on biomaterial scaffolds designed to mediate the development and maturation of vascular networks, by immobilized growth factors. The interactive effects of multiple vasculogenic factors are discussed in the context of cardiac tissue engineering.

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Tailoring Linear and Nonlinear Optical Properties of a Side‐Chain Liquid Crystalline Azo‐Polymethacrylate
Authors: Alicante Raquel , Cases Rafael , Villacampa Belén , Oriol Luis
Published: September 2010

The molecular orientation in a side‐chain liquid crystalline azopolymer with push–pull chromophores (Pol‐PZ‐CN) is studied by UV‐vis spectroscopy, refractive index and second harmonic generation measurements. Fresh films show homeotropic arrangement, but irradiation with polarized light induces “in‐plane” birefringence, which is enhanced by subsequent thermal annealing up to values as high as 0.34. The nonlinear response of Corona poled films with “in‐plane” anisotropy is governed by three independent NLO dij coefficients, evidencing symmetry different from the usual (C∞v). For irradiated films, stable values d31 = 1.4, d32 = 0.9 and d33 = 11 pm·V−1 are measured at 1.9 µm. A noticeable higher d31/d32 ratio is obtained for preirradiated and annealed films. The proposed two‐step method consisting of light irradiation and heating is an effective strategy to tailor the polar molecular orientation of nonlinear liquid crystalline azopolymers.

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Synthesis of π‐Conjugated Polymer Possessing Mercapto‐Substituted 1,3‐Butadiene‐1,4‐diyl Units by Reaction of Regioregular Organometallic Polymer Having Titanacyclopentadiene Moieties in the Main Chain
Authors: Nishiyama Hiroki , Tomita Ikuyoshi
Published: September 2010

A π‐conjugated polymer having 1,4‐bismercapto‐substituted 1,3‐diene units in the main chain was prepared by the novel polymer reaction of a regioregular organometallic polymer having titanacyclopentadiene‐2,5‐diyls units with benzenesulfenyl chloride. The number‐average molecular weight and the molecular weight distribution of the polymer derived from 1,4‐diethynyl‐2,5‐di(2‐ethylhexyloxy)benzene were estimated to be 5 700 and 1.6, respectively, from the GPC analysis. The π‐conjugated character, photoluminescence behavior both in solid‐state and solutions, and the electron‐donating properties of the π‐conjugated polymer are discussed on the basis of its UV‐vis spectrum, photoluminescence spectrum, and CV analysis.

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Systems of Singular Differential Operators of Mixed Order and Applications to 1 ‐ Dimensional MHD Problems
Authors: Hardt Volker , Mennicken Reinhard , Naboko Serguei
Published: September 2010

In some weighted L2 vector space we study a symmetric semibounded operator IL'0 which is given by a 3 x 3 system of ordinary differential operators on an intervall [0, ro] with a singularity at r = 0 (see (0.1)). This system can be considered as a “smooth” perturbation of a more specific physical model describing the oscillations of plasma in an equilibrium configuration in a cylindrical domain (see (1.12)). This perturbation is smooth in the sense that in the system under study in comparison with the physical model only the smooth parts of the coefficients are changed conserving all types of singularities. It is the goal of this paper to construct a suitable selfadjoint extension IL of the symmetric operator IL'0 (and its closure IL0) and to determine the essential spectrum of this extension. The essential spectrum consists of two bands (which may overlap) if we exclude the singularities by considering the system on an interval (r1,ro] with 0 < r1 < ro. In the corresponding physical model these bands are called Alfén spectrum and slow magnetosonic spectrum. It is shown that the singularity in 0 generates additional components of the essential spectrum which under specific conditions, as in the case of the physical model, “disappear” in the two bands known from the “regular” case (r1, ro) with r1 → 0.
On the Remainders of Asymptotic Expansions of Solutions of Linear Differential Equations near Irregular Singular Points of Higher Rank
Authors: Hoeppner Reinhard , Schäfke Reinhard
Published: September 2010

We study linear ordinary differential equations near singular points of higher Poincaré rank r under the condition that the leading matrix has distinct eigenvalues. It is well known that there are fundamental systems of formal vector solutions and that in certain sectors, there are actual rolutions having those as asymptotic expansions.

We study the corresponding remainders, in particular if the truncation point N and the independent variable z are coupled such that Nzr is approximately constant. We show that the remainders are exponentially small under this condition and how to choose the constant optimally. Furthermore, we obtain precise asymptotic expansions for these remainders.

As corollaries, we obtain well known asymptotic expansions for the coefficients in the formal solutions and limit formulas for Stokes' multipliers.

The method of proof only uses functions in the original z ‐ plane and its main tools are the Cauchy ‐Heine theorem and the saddle‐point method.
On Representations of Matrix Valued Nevanlinna Functions by u ‐ Resolvents
Authors: Kaltenbäck Michael , Woracek Harald
Published: September 2010

We show that every matrix valued generalized Nevanlinna function can be represented as a u‐resolvent of a certain selfadjoint relation acting in a Pontryagin space. The negative index of this Pontryagin space may be larger than the number of negative squares of the given function. The minimal index of negative squares which is needed to obtain such a representation is determined. In the case of scalar functions, the results presented give rise to some new classes of generalized Nevanlinna functions.
Decomposition Theorems for α ‐‐ Symmetric Positive Definite Functions
Authors: Gneiting Tilmann
Published: September 2010

We show that every measurable, α‐symmetric positive definite function on IRn (n ≥ 2) is continuous, except possibly at the origin.
K ‐‐ Convex Operators and Walsh Type Norms
Authors: Hinrichs Aicke
Published: September 2010

A celebrated result of G. Pisier states that the notions of B‐convexity and K‐convexity coincide for Banach spaces. We complement this in the setting of linear and bounded operators between Banach spaces. Our approach is local and even yields inequalities between gradations of K‐convexity norms and Walsh type norms of operators. Our method combines G. Pisier's original ideas and the main steps in the proof of the Beurling‐Kato theorem on extensions of C0‐semigroups of operators to holomorphic semigroups with the technique of ideal norms.
Roles of Interlayers in Efficient Organic Photovoltaic Devices
Authors: Park Jong Hyeok , Lee Tae‐Woo , Chin Byung‐Doo , Wang Dong Hwan , Park O Ok
Published: September 2010

This review discusses interfacial layers in organic photovoltaic devices. The first part of the review focuses on the hole extraction layer, which is located between a positive electrode and an organic photoactive material. Strategies to improve hole extraction from the photoactive layer include incorporation of several different types of hole extraction layers, such as conductive polymeric materials, self‐assembled molecules and metal oxides, as well as surface treatment of the positive electrodes and the conductive polymeric layers. In the second part, we review recent research on interlayers that are located between a negative electrode and a photoactive layer to efficiently extract electrons from the active layer. These materials include titanium oxides, metal fluorides and other organic layers.

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Facile Synthesis of Double‐Shelled Polypyrrole Hollow Particles with a Structure Similar to That of a Thermal Bottle
Authors: Bai Meng‐Yi , Xia Younan
Published: September 2010

Polystyrene (PS) hollow spheres containing a hole on the surface were used as templates to fabricate double‐shelled polypyrrole (PPy) hollow particles with a unique structure similar to that of a thermal bottle. Thanks to the hole on the surface, the monomer and initiator could easily and quickly diffuse into the interior of the PS hollow sphere to generate uniform PPy coatings on both the inner and outer surfaces of the hollow template. When the PS template was selectively removed with tetrahydrofuran, we obtained a double‐shelled hollow particle with a structure resembling that of a thermal bottle. We also demonstrated that the morphology and porosity of the resultant PPy coatings could be manipulated and fine‐tuned by adjusting at least three parameters: the concentration of monomer, the polymerization time, and the addition of poly(vinyl pyrrolidone).

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Homogeneous Phase Copolymerizations of Vinylidene Fluoride and Hexafluoropropene in Supercritical Carbon Dioxide
Authors: Möller Eléonore , Beuermann Sabine
Published: September 2010

Copolymerizations of vinylidene fluoride (VDF) and hexafluoropropene (HFP) were carried out in homogeneous phase with supercritical carbon dioxide up to complete VDF conversion using conventional peroxide initiators. The HFP monomer feed ratios, fHFP, were varied between 0.65 and 0.20. Depending on fHFP amorphous or semi‐crystalline copolymers were obtained. fHFP also determines the minimum pressure required to allow for homogeneous phase reactions. For example, HFP‐rich copolymerizations in 70 wt.‐% CO2 at 100 °C require a pressure of around 500 bar. Further, bulk copolymerizations in homogenous phase were feasible for fHFP = 0.65 at 900 bar up to complete VDF conversion. Copolymerizations in the presence of perfluorinated hexyl iodide carried out at 75 °C gave access to low dispersity polymers. Due to homogeneous phase conditions the use of any surfactants or fluorinated cosolvent is avoided.

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An experimental study on the early stages of gas‐phase olefin polymerizations using supported Ziegler–Natta and metallocene catalysts
Authors: Machado Fabricio , Lima Enrique Luis , Pinto José Carlos , McKenna Timothy F.
Published: September 2010

The initial stages of gas‐phase polymerizations of propylene and ethylene are analyzed using a fixed bed stopped flow reactor. The very early development of particle morphology and polymer properties is analyzed for three different commercial catalyst systems: MgCl2‐ and SiO2‐supported Ziegler–Natta and SiO2‐supported metallocene. It is shown that, depending on the operating conditions, distinct nonuniform catalyst fragmentation patterns can develop, confirming different scenarios described by published fragmentation models. In addition, it is shown that the molecular weight distributions and polymer yields obtained during the very early stages of the polymerization suggest the existence of significant temperature gradients inside the growing polymer particles. Finally, it is shown that the ratio of catalyst to glass beads in the bed can have a pronounced effect on the evolution of the polymerization reaction. This can be interpreted in terms of the significant temperature difference between the polymer particles and the gaseous monomer stream. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers
Synthesis and properties of mesogen‐jacketed liquid crystalline polymers containing bistolane mesogen
Authors: Zhang Zhen Lin , Zhang Lan Ying , Shen Zhi Hao , Xing Guang Zhong , Fan Xing He , Zhou Qi Feng
Published: September 2010

On the basis of the concept of mesogen‐jacketed liquid crystalline polymers, a series of new methacrylate monomers, (2,5‐bis[2‐(4′‐alkoxyphenyl) ethynyl] benzyl methacrylate (MACn, n = 4, 6, 8, 10, and 12) and 2,5‐bis[2‐(6′‐decanoxynaphthyl) ethynyl] benzyl methacrylate (MANC10), and their polymers, PMACn (n = 4, 6, 8, 10, and 12) and PMANC10 were synthesized. The bistolane mesogen with large π‐electron conjugation were side‐attached to the polymer backbone via short linkages. Various characterization techniques such as differential scanning calorimetry, wide‐angle X‐ray diffraction, and polarized light microscopy were used to study their mesomorphic phase behavior. The polymer PMACn with shorter flexible substituents (n = 4) forms the columnar nematic (ϕN) phase, but other polymers with longer flexible tails (n = 6, 8, 10, and 12) can develop into a smetic A (SA) phase instead of a ϕN phase. The PMANC10 containing naphthyl can also form a well‐defined SA phase. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Well‐defined amphiphilic poly(p‐dioxanone)‐grafted poly(vinyl alcohol) copolymers: Synthesis and micellization
Authors: Wu Gang , Chen Si‐Chong , Zhan Qi , Wang Yu‐Zhong
Published: September 2010

A series of amphiphilic biodegradable and biocompatible poly(p‐dioxanone)‐grafted poly(vinyl alcohol) (PVA) copolymers with well‐defined structure were obtained by a three‐step synthesis based on the “grafting from” concept. The first step (protection step), called the partial silylation of PVA hydroxyl groups, was accomplished by 1,1,1,3,3,3‐hexamethyldisilazane and catalyst chlorotrimethylsilane in dimethyl sulfoxide using THF as cosolvent. The second step was the ring‐opening polymerization of p‐dioxanone (PDO) initiated from the remaining OH groups of the partially silylated PVA. Finally, a deprotection step was followed: the silylether group was deprotected easily under very mild conditions. The synthetic conditions of the first two steps were investigated, and the structures of polymers formed in each step were characterized by various analytical methods. The results showed that the molecular structure of the PVA‐g‐PPDO could be controlled easily by the degree of silylation and the feed ratio. In addition, the micellization of amphiphilic PVA‐g‐PPDO copolymers in water was proved by fluorescence spectra and dynamic light scattering, and the relationship between structural parameters of copolymers and micellar properties was studied preliminarily. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Synthesis and applications of low‐bandgap conjugated polymers containing phenothiazine donor and various benzodiazole acceptors for polymer solar cells
Authors: Padhy Harihara , Huang Jen‐Hsien , Sahu Duryodhan , Patra Dhananjaya , Kekuda Dhananjay , Chu Chih‐Wei , Lin Hong‐Cheu
Published: September 2010

A series of soluble donor‐acceptor conjugated polymers comprising of phenothiazine donor and various benzodiazole acceptors (i.e., benzothiadiazole, benzoselenodiazole, and benzoxadiazole) sandwiched between hexyl‐thiophene linkers were designed, synthesized, and used for the fabrication of polymer solar cells (PSC). The effects of the benzodiazole acceptors on the thermal, optical, electrochemical, and photovoltaic properties of these low‐bandgap (LBG) polymers were investigated. These LBG polymers possessed large molecular weight (Mn) in the range of 3.85−5.13 × 104 with high thermal decomposition temperatures, which demonstrated broad absorption in the region of 300−750 nm with optical bandgaps of 1.80−1.93 eV. Both the HOMO energy level (−5.38 to −5.47 eV) and LUMO energy level (−3.47 to −3.60 eV) of the LBG polymers were within the desirable range of ideal energy level. Under 100 mW/cm2 of AM 1.5 white‐light illumination, bulk heterojunction PSC devices containing an active layer of electron donor polymers mixed with electron acceptor [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) or [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) in different weight ratios were investigated. The best performance of the PSC device was obtained by using polymer PP6DHTBT as an electron donor and PC71BM as an acceptor in the weight ratio of 1:4, and a power conversion efficiency value of 1.20%, an open‐circuit voltage (Voc) value of 0.75 V, a short‐circuit current (Jsc) value of 4.60 mA/cm2, and a fill factor (FF) value of 35.0% were achieved. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Efficient gel‐type electrolyte with bismaleimide via in situ low temperature polymerization in dye‐sensitized solar cells
Authors: Chen Jian‐Ging , Liu Ken‐Yen , Chen Chia‐Yuan , Lin Chia‐Yu , Huang Kuan‐Chieh , Lai Yi‐Hsuan , Wu Chun‐Guey , Lin King‐Fu , Ho Kuo‐Chuan
Published: September 2010

This study reports the characteristics of gel‐type dye‐sensitized solar cells (DSSCs), fabricated with gel‐type electrolyte containing poly‐1,1′‐(methylenedi‐4,1‐phenylene)bismaleimide (PBMI), or poly‐1,1′‐(3,3′‐dimethyl‐1,1′‐biphenyl‐4,4′‐diyl)bismaleimide (PDBBMI), or poly‐N,N′‐(4‐methyl‐1,3‐phenylene)bismaleimide (PMPBMI), prepared by in situ polymerization of the corresponding monomer without an initiator at 30 °C. Incorporating 0.3 wt % content of exfoliated alkyl‐modified nanomica (EAMNM) into PBMI‐gelled electrolyte leads to higher short‐circuit current density (Jsc = 17.14 mA cm−2) and efficiency (η = 7.02%) than that of neat PBMI‐gel electrolyte (Jsc = 15.32 mA cm−2, η = 6.41%). Incorporating 0.3 wt % EAMNM into PBMI‐gelled electrolyte results in remarkably stable device performance under continuous light soaking under one sun (100 mW cm−2) at 55 °C. The efficiency of DSSCs based on PBMI/0.3 wt % EAMNM‐gelled electrolyte drops by only 1.7% (η = 6.93%) after 500 h of continuous light soaking. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Plasma Activation and Self Bonding of PEEK for the Use in the Encapsulation of Medical Implants
Authors: Awaja Firas , Zhang Shengnan , James Natalie , McKenzie David R.
Published: September 2010

Polyether ether ketone (PEEK) and its composites have emerged as one of the main candidate materials for replacing titanium and its alloys for the encapsulating components of medical implants. PEEK, however, is a difficult material to bond without the use of adhesion promoting agents. Experiments based on the central composite rotatable design (CCRD) were used to find an optimum plasma surface modification treatment. X‐ray photoelectron spectrometry (XPS), contact angle measurements and scanning electron microscopy (SEM) were used to provide surface molecular and thermodynamic information. Higher self bond strength of PEEK was found to correlate with higher relative oxygen concentration and total surface energy. Mechanisms for the autohesive bond formation were developed based on the oxidation of the surface.

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Proteomics profile of cellular response to chiral drugs: Prospects for pharmaceutical applications
Authors: Ching Chi Bun , Zhang Jianhua , Sui Jianjun , Chen Wei Ning
Published: September 2010

This article was originally published in Proteomics 2010, 10, 888–893, DOI 10.1002/pmic.200900094
Differential protein expression on the cell surface of colorectal cancer cells associated to tumor metastasis
Authors: Luque‐García Jose Luis , Martínez‐Torrecuadrada Jorge Luis , Epifano Carolina , Cañamero Marta , Babel Ingrid , Casal J. Ignacio
Published: September 2010

This article was originally published in Proteomics 2010, 10, 940–952, DOI 10.1002/pmic.200900441
The impact of miR‐34a on protein output in hepatocellular carcinoma HepG2 cells
Authors: Cheng Jun , Zhou Lin , Xie Qin‐Fen , Xie Hai‐Yang , Wei Xu‐Yong , Gao Feng , Xing Chun‐Yang , Xu Xiao , Li Lan‐Juan , Zheng Shu‐Sen
Published: September 2010

This article was originally published in Proteomics 2010, 10, 1557–1572, DOI 10.1002/pmic.200900646
Phosphoproteome analysis of human liver tissue by long‐gradient nanoflow LC coupled with multiple stage MS analysis
Authors: Han Guanghui , Ye Mingliang , Liu Hongwei , Song Chunxia , Sun Deguang , Wu Yifeng , Jiang Xinning , Chen Rui , Wang Chunli , Wang Liming , Zou Hanfa
Published: September 2010

This article was originally published in Electrophoresis 2010, 31, 1080–1089, DOI 10.1002/elps.200900493
CE‐MS and related techniques as a valuable tool in tumor biomarkers research
Authors: Colnaghi Simionato Ana Valéria , Carrilho Emanuel , Franco Marina , Tavares Maggi
Published: September 2010

This article was originally published in Electrophoresis 2010, 31, 1214–1226, DOI 10.1002/elps.200900671
Pressurization of fixed roof storage tanks due to external fires
Authors: Fouillen Fabien , Duplantier Stéphane
Published: September 2010

When a fixed roof storage tank is surrounded by a pool fire, and when the vents are not correctly dimensioned, the inside pressure can raise until the mechanical limits of the structure. The aim of this study is to develop a tool that will allow to follow the variations of the pressure and temperature in the gas phase, as a function of the size of the vent. This will help the sizing of new tank's vents or evaluating the risk of already build structures. The model also gives the temperature's distribution in the liquid phase, at each time step. In case of undersized vents, this information will be convenient to describe the phenomenological aspect of the accident after the rupture of the tank, i.e., to qualify and quantify the fire ball generated and its effect on persons and structures. Currently, if few analytical models exist to quantify the fire ball and its effects after the rupture, none are able to describe with accuracy the prerupture phenomena. The tool developed takes into account the two phases of the accident and allows to study complete and consistent scenarii. © 2010 American Institute of Chemical Engineers Process Saf Prog, 2011
Using hazards assessment to prevent loss of containment
Authors: Dharmavaram S. , Klein James A.
Published: September 2010

Preventing loss of containment of materials and/or energy is a primary goal of industrial Process Safety Management programs. A thorough understanding of the hazards, identification of a complete range of failure events, detailed analysis of the consequences of failure events, and the analysis of process risks accounting for all the safeguards can help significantly in preventing and mitigating loss of containment incidents. In this article, additional details are provided on hazard assessment approaches, consequence analysis of potential events, and risk analysis for minimizing risks. © 2010 American Institute of Chemical Engineers Process Saf Prog, 2010