bluuebunny/crossref_metadata_2025 huggingface dataset:
Membranes based on polyimide–polyaniline nanocomposites for pervaporation of organic mixtures
Authors: Polotskaya G. A. , Meleshko T. K. , Sushchenko I. G. , Yakimansky A. V. , Pulyalina A. Yu. , Toikka A. M. , Pientka Z.
Published: April 2010

Polyimide–polyaniline nanocomposites were obtained by mixing poly{[4,4′‐bis(4″‐N‐phenoxy)diphenylsulfone]imide‐1,3‐bis(3,4‐dicarboxyphenoxy)benzene} (PI) and polyaniline (PANI) solutions in N‐methylpyrrolidone. These solutions were used for the preparation of homogeneous and composite membranes. Uniform distribution of PANI particles in the membranes, resulted from interactions between macromolecules, was confirmed by transmission electron microscopy. Membranes based on PI and PI–PANI were tested in pervaporation of binary organic mixtures: methanol/toluene and methanol/cyclohexane and showed a remarkable selectivity with respect to methanol. In both pervaporation processes, selectivity was improved in PANI‐containing membranes. Interactions between membrane polymers and liquid penetrants (methanol, toluene, and cyclohexane) were studied by measurements of surface tension, sorption, and pervaporation parameters. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Studies on conductivity of acrylonitrile‐butadiene rubber/LiClO4 composite and its modification by adding epoxy resin
Authors: Zhang Qian , Ren Wentan , Yu Haiyang , Zhang Yong
Published: April 2010

Solid polymer electrolytes based on acrylonitrile‐butadiene rubber (NBR) and LiClO4 were prepared and their conductivity was evaluated. The effect of nitrile group CN/LiClO4 mole ratio on the conductivity was investigated. The maximum conductivity of 1.21 × 10−4 S cm−1 (20°C) was achieved in the NBR/LiClO4 composite at the CN/LiClO4 mole ratio of 1/2.5, which was in accordance with the strongest coordination between CN and Li+ indicated by Fourier transform infrared spectrometry measurement. The conductivity was further increased by two to three times when 30 phr epoxy resin was introduced into NBR, and the conductivity could retain around the maximum value with the CN/LiClO4 mole ratio ranged from 1/2.5 to 1/3.5, while the conductivity of NBR/LiClO4 composite existed a decrease in the same range. Field emission scanning electron microscopy and atomic force microscopy characterization showed that epoxy resin significantly improved the dispersion of LiClO4, leading to better surface smoothness of NBR/epoxy resin/LiClO4 composite film and contributing to the increase of ionic conductivity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Electroresponsive behavior of a sulfonated poly(vinyl alcohol) hydrogel and its application to electrodriven artificial fish
Authors: Yang Shiwen , Liu Genqi , Wang Xiaoqiang , Song Jinyue
Published: April 2010

A novel sulfonated poly(vinyl alcohol) hydrogel was prepared by the sulfonation of a semicarbonized poly(vinyl alcohol) hydrogel with concentrated sulfuric acid, and its swelling properties, mechanical properties, and electroresponsive behavior in Na2SO4 solutions were studied. The results indicated that the hydrogel had a sandwich‐type structure, and this was confirmed by scanning electron microscopy. The water take‐up ability of the hydrogel decreased with the ionic strength of the Na2SO4 solution increasing. Young's modulus, the elongation at break, and the tensile strength of the hydrogel swollen in deionized water were 1.36 MPa, 165%, and 2.93 MPa, respectively. The hydrogel swollen in an Na2SO4 solution bent toward the cathode under noncontact direct‐current electric fields, and its bending speed and equilibrium strain increased with the applied voltage increasing. There was a critical ionic strength of 0.03 at which the maximum equilibrium strain of the hydrogel occurred. With cyclical changes in the direction of the applied potential, the hydrogel exhibited good reversible bending behavior. On this basis, an artificial fish was designed. Under a cyclically varying electric field (the period was 2 s, and the voltage ranged from −15 to 15 V), the swimming speed of the artificial fish could reach 9.6 cm/min in an Na2SO4 solution with an ionic strength of 0.03. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A molecularly imprinted polymer via a salicylaldiminato‐based cobalt(III) complex: A highly selective solid‐phase extractant for anionic reactive dyes
Authors: Abu‐Surrah Adnan S. , Al‐Degs Yahya S.
Published: April 2010

A novel molecularly imprinted polymer based on tert‐butyl acrylate (MIP‐BA) was fabricated with the assistance of a cobalt(III)‐based catalyst bearing an N‐salicylidene isopropylamine ligand [(SPA)2CoCl]. After initiation with methyl aluminoxane, the catalyst system was found to be active toward the polymerization of tert‐butyl acrylate (t‐BA) in the presence of a polar template (Cibacron reactive red dye) and divinylbenzene (DVB) as a crosslinker. Polymerization experiments, including those of t‐BA, t‐BA, and DVB and t‐BA and dye, were also carried out. Isolated blank polymers and MIP‐BA were analyzed with a variety of techniques, including differential scanning calorimetry, thermogravimetric analysis, gel permeation chromatography, infrared spectroscopy, nuclear magnetic resonance, and ultraviolet–visible spectroscopy. In general, the complex showed moderate polymerization activity and produced high‐molar‐mass poly(tert‐butyl acrylate); however, a decrease in the monomer conversion was observed upon the addition of the dye and/or the crosslinker. The effect of imprinting was obvious when the adsorption capacity of MIP‐BA measured at pH 6 for red dye (the imprinted molecule) was increased from 9.2 to 90.4 mg/g after imprinting. Competitive adsorption studies revealed that the dye‐imprinted polymer enabled the efficient uptake of red dye, even in the presence of blue and yellow dyes that had similar chemical structures to the imprinted molecule. The selectivity coefficients were 43 and 36 with respect to the blue and yellow dyes, respectively. The proposed polymerization procedure could be extended to other anionic polar reactive dyes and polar reactive polymers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Structure, mechanical properties, and gas permeability of elastomers based on polybutadiene and epoxy resin
Authors: Zhang Xiaomo , Ji Shi , Quan Yiwu , Chen Qingmin , Chang Pengshan
Published: April 2010

In this study, the structure, gas permeability, and mechanical properties of new elastomers based on liquid polybutadiene and epoxy resin were investigated by dynamic mechanical thermal analysis, thermogravimetric analysis, stress–strain analysis, and water‐resistance and gas permeability tests. The results reveal that there was complete phase separation between the epoxy resin and polybutadiene. With increasing epoxy resin content, the glass‐transition temperature of the soft segment varied little. These elastomers had tensile strengths of 6–10 MPa and ultimate elongations of 500–100% according to the different epoxy resin contents. Thermogravimetric analysis revealed that these elastomers had better thermal stability, with a 5% weight loss at a temperature of around 350°C. The gas permeabilities of these elastomers were measured to be 13.2–15.3 barrers for oxygen, 4.8–5.3 barrers for nitrogen, and 28–35 barrers for carbon dioxide at 23°C. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of the radiation grafting conditions on the cross‐sectional distribution of poly(vinylbenzyl chloride) grafted polymer onto poly(tetrafluoroethylene‐co‐hexafluoropropylene) films
Authors: Fei Geng , Kang Sung‐A , Ko Beom‐Seok , Lee Youn‐Sik , Chang Nho Young , Shin Junhwa
Published: April 2010

Poly(vinylbenzyl chloride) (PVBC)‐grafted poly(tetrafluoroethylene‐co‐hexafluoropropylene) (FEP) films were prepared as precursors for ion‐exchange membranes with a radiation grafting technique. A scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM‐EDX) instrument was used to investigate the effects of the radiation grafting conditions on the distribution profiles of the grafts in the FEP‐g‐PVBC films because the properties of the ion‐exchange membranes were largely affected not only by the degree of grafting (DOG) but also by the distribution of the graft chain. These results indicate that the distribution profile of the grafts largely depended on the grafting parameters, such as the solvent, monomer concentration, film thickness, and irradiation dose. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Glass‐transition and gas‐transport characteristics of polymer nanocomposites based on crosslinked poly(ethylene oxide)
Authors: Comer Anthony C. , Kalika Douglass S. , Kusuma Victor A. , Freeman Benny D.
Published: April 2010

The glass‐transition and gas‐transport properties of rubbery polymer nanocomposites based on crosslinked poly(ethylene oxide) and metal oxide nanoparticles were studied. Nanocomposite samples were prepared by the UV photopolymerization of poly(ethylene glycol) diacrylate (n ∼ 14) in the presence of magnesium oxide or silica nanoparticles. The thermomechanical properties of the composites were investigated with dynamic mechanical and dielectric spectroscopy methods. The inclusion of nanoparticles in the crosslinked poly(ethylene glycol) diacrylate network led to a systematic increase in rubbery modulus and a modest positive offset (∼6°C) in the measured glass‐transition temperature for both systems. Bulk density measurements indicated only minimal void volume fraction in the composites, and CO2 and light gas permeability decreased with particle loading; for example, the CO2 infinite dilution permeability at 35°C decreased from 106 barrer in the unfilled polymer to 55 barrer in a nanocomposite containing 30 wt % magnesium oxide nanoparticles. The inclusion of toluene diluent in the prepolymerization mixtures produced a limited enhancement in sample permeability, but the sizeable increases in gas transport with particle loading reported for certain other rubbery nanocomposite systems were not realized in the crosslinked poly(ethylene glycol) diacrylate composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and properties of organic–inorganic hybrid composites based on polystyrene and an incompletely condensed polyvinylsilsesquioxane oligomer
Authors: Dai Zhen , Zhao Ning , Fan Haosen , Zhang Liang , Zhang Xiaoli , Xu Jian
Published: April 2010

An incompletely condensed polyvinylsilsesquioxane (PVSQ) oligomer containing abundant silanol groups was synthesized and characterized by FTIR, 1H‐NMR, 29Si‐NMR, and MALDI‐TOF‐MS. Polystyrene/polyvinylsilsesquioxane (PS/PVSQ) hybrid composites were prepared by an in situ bulk polymerization. The hybrid composites showed higher Tg, Td, and char yield than PS homopolymer and without mechanical loss. The improvements in the properties of PS/PVSQ hybrid composites can be ascribed to the crosslinking function of PVSQ by silanol condensation in later processing. The hybrids showed different morphology from discrete microstructure to continuous network depending on the concentration of PVSQ. Because of the surface enrichment, a PVSQ protection layer was formed, which made the hybrid surface more hydrophobic. The structure and the reaction mechanism of PS/PVSQ hybrid composites were also investigated. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Investigation of the effect of delayed reflux on PVC grain properties produced by suspension polymerization
Authors: Etesami N. , Nasr Esfahany M. , Bagheri R.
Published: April 2010

The effects of the condenser operation on properties of polyvinyl chloride (PVC) particles produced by suspension polymerization process were investigated in a pilot scale reactor. It was observed that delaying reflux operation increased the cold plasticizer absorption of the final resin. Both bulk density and K‐value of the PVC powder decreased by increasing time delay in the reflux operation. It was also found that commencement of refluxing before 20% conversion resulted in bimodal particle size distribution (PSD), while monomodal PSD was obtained for longer delays in refluxing. SEM micrographs showed that surface of produced particles were rough and smooth when reflux started before and after 20% conversion, respectively. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Hydroxyethyl chitosan‐g‐poly(acrylic acid‐co‐sodium acrylate) superabsorbent polymers
Authors: Yu Chen , Yun‐Fei Liu , Hui‐Min Tan
Published: April 2010

A novel hydroxyethyl chitosan‐g‐poly(acrylic acid‐co‐Sodium Acrylate) (HECTS‐g‐(PAA‐co‐PSA)) superabsorbent polymer was prepared through graft copolymerization of acrylic acid and sodium acrylate onto the chain of hydroxyethyl chitosan. The structure of the polymer was characterized by FTIR. By studying the water absorption of the polymer synthesized under different conditions, the optimal conditions for synthesizing the polymer with the highest swelling ratio was defined. This superabsorbent polymer was further treated by the solvent precipitation method and by the freeze‐drying method. We found that the water absorption rate of the treated polymer was greatly increased and the microstructure of the treated polymer was changed from small pores to loose macro pores. The swelling processes of the polymers before and after modification fit first‐order dynamic processes. The amount of the residual acrylic acid was greatly decreased after treatments. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Sorption of methane, nitrogen, carbon dioxide, and water in Matrimid 5218
Authors: Scholes Colin A. , Tao Wen Xian , Stevens Geoff W. , Kentish Sandra E.
Published: April 2010

The sorption of the light gases CH4, N2, CO2 as well as water into polymer films prepared from a commercial sample of 3,3′‐4, 4′‐benzophenone tetracarboxylic‐dianhydride diaminophenylindane (Matrimid 5218) are measured. The light gas isotherms follow standard dual‐sorption behavior for polymeric films with the Henry's Law coefficient correlated to the Lennard‐Jones well depth parameter. Water sorption behavior was similar to rubbery polymers, that of significant adsorption into the polymeric matrix and was modeled by Henry's law exclusively. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effects of diazonaphthoquinone groups on photosensitive coating
Authors: Zhou Haihua , Zou Yingquan , Song Yanlin
Published: April 2010

Diazonaphthoquinone (DNQ)‐novolak photosensitive materials are important in lithography. DNQ groups play an important role in the photosensitive coating. However, there are no reports on the relationship between content of DNQ groups and properties of the coating. The properties include alkali resistance, isopropanol resistance, and abrasion resistance, the key factors in lithography. The experimental results show proper content of DNQ groups can ensure higher sensitivity, finer resolution, and better abrasion resistance in lithography. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and characterization of low‐dielectric photosensitive polyimide/silica hybrid materials
Authors: Srisuwan Suttisak , Thongyai Supakanok , Praserthdam Piyasan
Published: April 2010

Photosensitive polyimide/silica hybrid materials were synthesized by reaction between 4,4′‐hexafluoroisopropylidene diphthalic anhydride (6FDA) and 4,4′‐oxydianiline. The intrachain chemical bonding and the interchain hydrogen bonding between the polyimide and silica moieties were increased by the incorporation of 2‐(dimethylamino) ethyl acrylate and 3‐aminopropyl trimetho xysilane, respectively. The photoinitiator was bis(2,4,6‐trimethyl benzoyl) phenylphosphine oxide (Irgacure‐819). The various coupling agents were utilized included tetrakis (allyloxy) silane (TAL). Most silica hybrid films showed better volume shrinkage and temperature resistance. The cooperation of octavinyl POSS, as the coupling agent, can lower dielectric constant (k) down to 2.48 but with the poorer volume shrinkage and temperature resistance than the other silica hybrid films. The addition of tetramethyl orthosilicate and 3‐methacryloxy propyltrimethoxysilane with silica content of 5.6 wt % can reduce k down to 2.26 but with worse volume shrinkage than the incorporation with TAL. The TAL hybrid film with degree of polymerization of 25 showed the best properties that optimized photolithography, dielectric constant (k = 3.81), volume shrinkage, and temperature resistance (Td5% = 378°C) with only 0.22 wt % silica content. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Former distribution and decline of the burbot (Lota lota) in the UK
Authors: Worthington T. , Kemp P. , Osborne P. E. , Howes C. , Easton K.
Published: April 2010

Species reintroductions are an increasingly fashionable tool among conservation practitioners for restoring locally and nationally extinct populations. For a reintroduction programme to be successful, an understanding of the causes of the decline of a species is required. This, however, proves challenging when baseline data on the distribution and abundance of the species are limited.

This paper uses evidence from historical literature to map the former distribution of the burbot (Lota lota) within UK rivers before its extinction in the early 1970s. A scoring system was developed to model anecdotal descriptions of burbot abundance from the collected literature.

The former distribution was divided into four geographical areas based loosely on catchment boundaries. The literature identifies 42 rivers in eastern England in which the burbot was likely to have existed. The status of the species in the Thames catchment is still unclear as information from written sources is contradicted by evidence from the archaeological record.

The findings indicate that the year of source data was a significant predictor of burbot abundance across the former population as a whole and for three of the four geographical areas (the Trent catchment, the Fenland rivers and the Yorkshire rivers). The timing of the burbot's decline showed differences between the geographical regions, with the Trent catchment exhibiting an earlier decline than the Fenland and Yorkshire areas. Copyright © 2010 John Wiley & Sons, Ltd.
Hepatocyte Growth Factor Induces Invasion and Migration of Ovarian Cancer Cells by Decreasing the Expression of E‐cadherin, β‐catenin, and Caveolin‐1
Authors: Hu Jun , Shao Shujuan , Song Yang , Zhao Jinyao , Dong Yan , Gong Linlin , Yang Peiman
Published: April 2010

Distant metastases are unusual occurrences at presentation and during the progression of epithelial ovarian cancer. There are no good clinical predictors of this phenomenon. In this study, we examined the role of hepatocyte growth factor (HGF) in cell metastasis in ovarian cancer HO8910 cells. We found that HGF has functions in biological processes essential to metastasis, including morphological remodeling, invasion and migration (P = 0.000, P = 0.001). Western blotting showed that in HGF treated group, the expression of E‐cadherin, β‐catenin, and caveolin‐1 was decreased as compared with the control group (P = 0.000, P = 0.002, P = 0.000). Immunofluorescence staining demonstrated that the population of E‐cadherin, β‐catenin, and caveolin‐1 at the cell membrane was downregulated. Reverse transcriptase polymerase chain reaction analysis revealed the decreased expression of E‐cadherin, β‐catenin, and caveolin‐1 at the mRNA level. Our data indicated that HGF leads to downregulation of E‐cadherin, β‐catenin, and caveolin‐1, disassembly of cell–cell contacts, and invasion and migration enhancement in human ovarian cancer cells. Anat Rec 293:1125–1133, 2010. © 2010 Wiley‐Liss, Inc.
Onset of Apoptosis in the Cystic Duct During Metamorphosis of a Japanese Lamprey, Lethenteron reissneri
Authors: Morii Mayako , Mezaki Yoshihiro , Yamaguchi Noriko , Yoshikawa Kiwamu , Miura Mitsutaka , Imai Katsuyuki , Yoshino Hiroaki , Hebiguchi Taku , Hebiguchi Tatsuzo , Senoo Haruki
Published: April 2010

A nonparasitic lamprey in Japan, Lethenteron reissneri, stops feeding prior to the commencement of metamorphosis. Resumption of feeding cannot take place due to major alterations in the digestive system, including loss of the gall bladder (GB) and biliary tree in the liver. This degeneration of bile ducts is considered to depend on programmed cell death or apoptosis, but molecular evidence of apoptosis remains lacking. Using terminal deoxynucleotidyl transferase dUTP nick‐end labeling (TUNEL) staining and immunohistochemistry with an antibody against active caspase‐3, we showed that epithelial cells of the cystic duct (CD) and GB became TUNEL‐positive by the early metamorphosing stage. Immunohistochemical staining of active caspase‐3, a key mediator in the apoptotic cascade, showed that the apoptotic signal was initiated in the region around the CD in the late larval phase. In later stages, active caspase‐3‐positive epithelial cells were also observed in the large intrahepatic bile duct (IHBD) and peripheral small IHBDs. At the early metamorphosing stage, bile canaliculi between hepatocytes were dilated and displayed features resembling canaliculi in cholestasis. Onset of apoptosis around the CD, which is the pathway for the storage of bile juice, and progression of apoptosis towards the large IHBD, which is the pathway for the secretion of bile juice, may lead to temporary intrahepatic cholestasis. The present study represents the first precise spatial and temporal analysis of apoptosis in epithelial cells of the biliary tract system during metamorphosis of any lamprey species. Anat Rec 293:1155–1166, 2010. © 2010 Wiley‐Liss, Inc.
Ablation of Systemic Phosphate‐Regulating Gene Fibroblast Growth Factor 23 (Fgf23) Compromises the Dentoalveolar Complex
Authors: Chu E.Y. , Fong H. , Blethen F.A. , Tompkins K.A. , Foster B.L. , Yeh K.D. , Nagatomo K.J. , Matsa‐dunn D. , Sitara D. , Lanske B. , Rutherford R.B. , Somerman M.J.
Published: April 2010

Fibroblast growth factor‐23 (FGF23) is a hormone that modulates circulating phosphate (Pi) levels by controlling Pi reabsorption from the kidneys. When FGF23 levels are deficient, as in tumoral calcinosis patients, hyperphosphatemia ensues. We show here in a murine model that Fgf23 ablation disrupted morphology and protein expression within the dentoalveolar complex. Ectopic matrix formation in pulp chambers, odontoblast layer disruption, narrowing of periodontal ligament space, and alteration of cementum structure were observed in histological and electron microscopy sections. Because serum Pi levels are dramatically elevated in Fgf23−/−, we assayed for apoptosis and expression of members from the small integrin‐binding ligand, N‐linked glycoprotein (SIBLING) family, both of which are sensitive to elevated Pi
in vitro. Unlike X‐linked hypophosphatemic (Hyp) and wild‐type (WT) specimens, numerous apoptotic osteocytes and osteoblasts were detected in Fgf23−/− specimens. Further, in comparison to Hyp and WT samples, decreased bone sialoprotein and elevated dentin matrix protein‐1 protein levels were observed in cementum of Fgf23−/− mice. Additional dentin‐associated proteins, such as dentin sialoprotein and dentin phosphoprotein, exhibited altered localization in both Fgf23−/− and Hyp samples. Based on these results, we propose that FGF23 and (Pi) homeostasis play a significant role in maintenance of the dentoalveolar complex. Anat Rec 293:1214–1226, 2010. © 2010 Wiley‐Liss, Inc.
Histological and Ultrastructural Characterization of Developing Miniature Pig Salivary Glands
Authors: Zhou Jian , Wang Hao , Yang Guan , Wang Xuejiu , Sun Yilin , Song Tieli , Zhang Chunmei , Wang Songlin
Published: April 2010

Salivary glands are a classic model of organ development and differentiation. Miniature pigs are considered as a unique animal model for salivary gland researchers in the fields of gene transfer, radiation damage, and functional reconstruction. However, there is little information about the development of miniature pig salivary glands. The present article was designed to study the developmental stages of salivary glands in miniature pigs using histological and ultrastructural methods. Sections from E40, E60, E80, E95 embryos, and P0 pups were stained with hematoxylin–eosin, Alcian blue, or periodic acid‐schiff. Selected specimens were also processed for electron microscopy. The development of the miniature pig salivary glands can be divided into five different stages that refer to the stages of the developing mouse submandibular gland. The histological characteristics of the miniature pig salivary glands at different developmental stages were synchronously verified at the ultrastructural level. Interestingly, the development of the miniature pig parotid gland trailed that of the submandibular gland by ∼15 days. Our study provides first‐hand data regarding the morphological organogenesis of salivary glands in the miniature pig and provides a foundation for further research on this model. Anat Rec 293:1227–1239, 2010. © 2010 Wiley‐Liss, Inc.
The Anatomy of the Gastrointestinal Tract of the African Lungfish, Protopterus annectens
Authors: Icardo José M. , Wong Wai P. , Colvee Elvira , Loong Ai M. , Ip Yuen K.
Published: April 2010

The gastrointestinal tract of the African lungfish Protopterus annectens is a composite, which includes the gut, the spleen, and the pancreas. The gut is formed by a short oesophagus, a longitudinal stomach, a pyloric valve, a spiraling intestine, and a cloaca. Coiling of the intestine begins dorsally below the pylorus, winding down to form six complete turns before ending into the cloaca. A reticular tissue of undisclosed nature accompanies the winding of the intestinal mucosa. The spleen is located along the right side of the stomach, overlapping the cranial end of the pancreas. The pancreas occupies the shallow area, which indicates on the gut dorsal side the beginning of the intestine coiling. In addition, up to 25 lymphatic‐like nodes accompany the inner border of the spiral valve. The mesenteric artery forms a long axis for the intestine. All the components of the gastrointestinal tract are attached to each other by connective sheaths, and are wrapped by connective tissue, and by the serosa externally. We believe that several previous observations have been misinterpreted and that the anatomy of the lungfish gut is more similar among all the three lungfish genera than previously thought. Curiously, the gross anatomical organization is not modified during aestivation. We hypothesize that the absence of function is accompanied by structural modifications of the epithelium, and are currently investigating this possibility. Anat Rec 293:1146–1154, 2010. © 2010 Wiley‐Liss, Inc.
Ontogenetic Scaling of Caudal Fin Shape inSqualus acanthias(Chondrichthyes, Elasmobranchii): A Geometric Morphometric Analysis With Implications for Caudal Fin Functional Morphology
Authors: Reiss Katie L. , Bonnan Matthew F.
Published: April 2010

The shark heterocercal caudal fin and its contribution to locomotion are of interest to biologists and paleontologists. Current hydrodynamic data show that the stiff dorsal lobe leads the ventral lobe, both lobes of the tail are synchronized during propulsion, and tail shape reflects its overall locomotor function. Given the difficulties surrounding the analysis of shark caudal finsin vivo, little is known about changes in tail shape related to ontogeny and sex in sharks. A quantifiable analysis of caudal fin shape may provide an acceptable proxy for inferring gross functional morphology where direct testing is difficult or impossible. We examined ontogenetic and sex‐related shape changes in the caudal fins of 115Squalus acanthiasmuseum specimens, to test the hypothesis that significant shape changes in the caudal fin shape occur with increasing size and between the sexes. Using linear and geometric morphometrics, we examined caudal shape changes within the context of current hydrodynamic models. We found no statistically significant linear or shape difference between sexes, and near‐isometric scaling trends for caudal dimensions. These results suggest that lift and thrust increase linearly with size and caudal span. Thin‐plate splines results showed a significant allometric shape change associated with size and caudal span: the dorsal lobe elongates and narrows, whereas the ventral lobe broadens and expands ventrally. Our data suggest a combination of caudal fin morphology with other body morphology aspects, would refine, and better elucidate the hydrodynamic factors (if any) that underlie the significant shape changes we report here forS. acanthias. Anat Rec 293:1184–1191, 2010. © 2010 Wiley‐Liss, Inc.
Muscle Architecture in the Mystacial Pad of the Rat
Authors: Haidarliu Sebastian , Simony Erez , Golomb David , Ahissar Ehud
Published: April 2010

The vibrissal system of the rat is an example of active tactile sensing, and has recently been used as a prototype in construction of touch‐oriented robots. Active vibrissal exploration and touch are enabled and controlled by musculature of the mystacial pad. So far, knowledge about motor control of the rat vibrissal system has been extracted from what is known about the vibrissal systems of other species, mainly mice and hamsters, since a detailed description of the musculature of the rat mystacial pad was lacking. In the present work, the musculature of the rat mystacial pad was revealed by slicing the mystacial pad in four different planes, staining of mystacial pad slices for cytochrome oxidase, and tracking spatial organization of mystacial pad muscles in consecutive slices. We found that the rat mystacial pad contains four superficial extrinsic muscles and five parts of the M. nasolabialis profundus. The connection scheme of the three parts of the M. nasolabialis profundus is described here for the first time. These muscles are inserted into the plate of the mystacial pad, and thus, their contraction causes whisker retraction. All the muscles of the rat mystacial pad contained three types of skeletal striated fibers (red, white, and intermediate). Although the entire rat mystacial pad usually functions as unity, our data revealed its structural segmentation into nasal and maxillary subdivisions. The mechanisms of whisking in the rat, and hypotheses concerning biomechanical interactions during whisking, are discussed with respect to the muscle architecture of the rat mystacial pad. Anat Rec 293:1192–1206, 2010. © 2010 Wiley‐Liss, Inc.
Transcutaneous Electrical Nerve Stimulation on Yongquan Acupoint Reduces CFA‐Induced Thermal Hyperalgesia of Rats via Down‐Regulation of ERK2 Phosphorylation and c‐Fos Expression
Authors: Yang Lin , Yang Lianxue , Gao Xiulai
Published: April 2010

Activation of extracellular signal‐regulated kinase‐1/2 (ERK1/2) and its involvement in regulating gene expression in spinal dorsal horn, cortical and subcortical neurons by peripheral noxious stimulation contribute to pain hypersensitivity. Transcutaneous electrical nerve stimulation (TENS) is a treatment used in physiotherapy practice to promote analgesia in acute and chronic inflammatory conditions. In this study, a total number of 114 rats were used for three experiments. Effects of complete Freund's adjuvant (CFA)‐induced inflammatory pain hypersensitivity and TENS analgesia on ERK1/2 phosphorylation and c‐Fos protein expression were examined by using behavioral test, Western blot, and immunostaining methods. We found that CFA injection caused an area of localized swelling, erythema, hypersensitivity to thermal stimuli, the decreased response time of hind paw licking (HPL), as well as upregulation of c‐Fos protein expression and ERK2 phosphorylation in the ipsilateral spinal dorsal horn and the contralateral primary somatosensory area of cortex and the amygdala of rats. TENS on Yongquan acupoint for 20 min produced obvious analgesic effects as demonstrated with increased HPL to thermal stimuli of CFA‐treated rats. In addition, TENS application suppressed the CFA‐induced ERK2 activation and c‐Fos protein expression. These results suggest that down‐regulation of ERK2 phosphorylation and c‐Fos expression were involved in TENS inhibition on CFA‐induced thermal hyperalgesia of rats. Anat Rec 293:1207–1213, 2010. © 2010 Wiley‐Liss, Inc.
Enhancement of P‐Glycoprotein Expression by Hepatocyte Transplantation in Carbon Tetrachloride‐Induced Rat Liver
Authors: Yu Ming , Zhang Weiguang , Qin Lihua , Tian Long , Zhou Changman
Published: April 2010

The multidrug resistance protein P‐glycoprotein (P‐gp) is physiologically expressed at the bile canalicular membrane of the liver, where it participates in the biliary excretion of various lipophilic drugs. Chronic exposure to carbon tetrachloride (CCI4) is known to induce hepatic fibrosis resulting in hepatotoxicity. This study focuses on the effects of CCI4 and hepatic transplantation (HT) on the P‐gp expressions in rat liver. Male SD rats were treated with CCI4 to induce liver damage for 3, 7, 14, 21, and 28 days, respectively. Immunohistochemistry revealed that P‐gp was widely distributed in the liver and was spread from the cytoplasm to cell membrane of the rat liver. Western blot showed remarkable increase of P‐gp expression in 3 days CCI4‐treated rats, whereas, a continuous decrease in the P‐gp expression was seen in 7, 14, 21, and 28 days CCI4‐treated rats. After HT with cells from the normal rat liver, the level of P‐gp increased comparing with those from the sham operation. Blood biochemistry showed decreased levels of serum alanine transaminase, aspartate transaminase, and alkaline phosphatase and increased serum levels of triglyceride and total protein, which indicated the improved function of the liver damaged by CCI4. These results illustrate the variation of the expression of P‐gp in CCI4‐induced hepatic damage and an increase of P‐gp level after HT in the toxic liver induced by CCI4. We hypothesized that P‐gp may play a protective role in the process of liver injury. HT can be beneficial to ameliorate the rat liver functional damage induced by CCI4. Anat Rec 293:1167–1174, 2010. © 2010 Wiley‐Liss, Inc.
Developmental Profile of Claudin‐3, ‐5, and ‐16 Proteins in the Epithelium of Chick Intestine
Authors: Ozden Ozkan , Black Betty L. , Ashwell Christopher M. , Tipsmark Christian K. , Borski Russell J. , Grubb Brenda J.
Published: April 2010

Proteins in the claudin family are a main component of tight junctions and form a seal that modulates paracellular transport in intestinal epithelium. This research tests the hypothesis that claudins 3, 5, and 16 will appear in the epithelium of embryonic intestine during functional differentiation. Immunohistochemistry is utilized to explore the developmental patterns of claudin‐3, ‐5, and ‐16 proteins in the epithelium of embryonic chick intestine from 9 days prior to hatching through the early post‐hatch period. These claudin proteins either changed their cellular localization or first appeared around the time of hatching. After hatching, claudin‐3 expression was prominent in basal–lateral regions of the epithelium along the entire villus, but was absent from crypts. Claudin‐5 was expressed most strongly in the crypt and lower villus epithelium within junctional complexes, whereas immunostaining of claudin‐16 was localized within goblet cells of the upper villus region. The relative mRNA levels of claudin‐3, ‐5, and ‐16 showed similar patterns; transcript levels rose between 18 and 20 days of development, then dropped by 2 days post‐hatch. Results of this work indicate that the claudin proteins assume their final locations within the epithelium around the time of hatching, suggesting that in addition to their known barrier and fence functions within tight junctions, these claudins may have additional roles in the differentiation and/or physiological function of chick intestine. The localization of claudin‐16 to goblet cells and its distribution in the more mature cells of the upper villus region suggest an unexpected role in goblet cell maturation and mucus secretion. Anat Rec 293:1175–1183, 2010. © 2010 Wiley‐Liss, Inc.
Gene expression profile in the salivary glands of primary Sjögren's syndrome patients before and after treatment with rituximab
Authors: Devauchelle‐Pensec Valérie , Cagnard Nicolas , Pers Jacques‐Olivier , Youinou Pierre , Saraux Alain , Chiocchia Gilles
Published: April 2010

Objective

Primary Sjögren's syndrome (SS) is a complex disorder, in part due to B cell abnormalities. Although anti–B cell therapy is promising in primary SS, no treatment has yet been demonstrated to modify the disease course. This open‐label study was undertaken to evaluate the efficacy of rituximab in primary SS and to investigate whether expression of specific genes is associated with efficacy of this treatment.

Methods

Fifteen patients with primary SS were treated in an open‐label trial. Salivary gland biopsy specimens were obtained, and total RNA was extracted and amplified. Microarray analysis with the Affymetrix Human Genome U133 Plus 2.0 Array was used to analyze >54,000 transcripts, and potential pathways were identified.

Results

With gene expression data obtained before treatment, patients could be correctly classified in terms of whether they would be responders or nonresponders to rituximab. Gene pathway analysis demonstrated that the B cell signaling pathway was the most profoundly differentially expressed before treatment in the responders compared with nonresponders. Subclassification of patients based on the level of infiltration also demonstrated differential expression of genes belonging to the interferon (IFN) pathway between responders and nonresponders. Furthermore, unsupervised analysis based on gene expression modification before and after treatment allowed identification of 8 genes that were differentially expressed between responders and nonresponders, with the difference remaining significant after Bonferroni correction.

Conclusion

Our results demonstrate the ability to elaborate a set of genes predictive of rituximab efficacy and highlight the importance of studying the differential expression of B cell and IFN pathway signaling molecules in relation to the response to anti‐CD20 treatment. A randomized controlled study is currently ongoing to confirm these results.
A grid service‐based Distributed Network Simulation Environment for computer networks education
Authors: Bote‐Lorenzo Miguel L. , Asensio‐Pérez Juan I. , Gómez‐Sánchez Eduardo , Vega‐Gorgojo Guillermo , Alario‐Hoyos Carlos
Published: April 2010

This paper presents a Distributed Network Simulation Environment (DNSE) based on grid technology that, unlike the well‐known ns‐2 simulator, provides two important features that facilitate the study of network scenarios that require running multiple simulations. First, the DNSE is capable of automatically handling the realization of multiple distributed simulations with the aim of completing all simulations in a reasonable amount of time. Second, the DNSE integrates the realization of simulations with the analysis of their results in an intuitive GUI in order to relieve students from the burden of launching multiple simulations and handling the many output files that may be generated to study the results. The performance analysis of the DNSE shows that it can significantly reduce the time required to complete multiple simulations. Furthermore, the assessment of an experience with students evidence that the DNSE can successfully support a real learning scenario and that students prefer using the DNSE over the ns‐2. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 654–665, 2012
Too cheap to chug: frugality as a buffer against college‐student drinking
Authors: Rose Paul , Smith Shannon Toney , Segrist Daniel J.
Published: April 2010

Beyond its probable effect on preventing financial problems, frugality may contribute to consumer well‐being in other ways. Using survey data collected from American undergraduates, in this paper we demonstrate that frugality is negatively associated with several types of alcohol use. These relationships hold even when sex and impulsivity are controlled. To further substantiate the link between frugality and college‐student drinking, we confirmed that typical amount spent on alcohol mediates the relations between frugality and each type of drinking we assessed. These results are consistent with suggestions that young adults' drinking‐related choices are subject to price considerations and that policy makers may be able to leverage such considerations to prevent excessive drinking.

Copyright © 2010 John Wiley & Sons, Ltd.
Wiki based management of chemometric research projects
Authors: Alsberg Bjørn K. , Clare Amanda
Published: April 2010

As research projects grow in size, there is a tendency for the number of management tasks to increase even faster. There are many different data objects and relations which need to be managed as part of the whole project: raw data, script files, function files, results, plots, tables etc.

Here it is suggested that a combination of wiki and version control software can be used as very effective and efficient tools in the management of chemometric research projects. A wiki provides a system for editing, viewing and navigating hyperlinked documents using web browsers. Easy syntax allows fast construction of web pages and hyperlinks without having to write HTML. Version control systems provide shared storage for source code and data (such as m‐files, Python and Perl scripts, plot and diagram source files, LaTeX files etc). Items stored in version control are given version numbers and can be retrieved, worked upon and updated by multiple users in different locations without conflict.

At the top level of a project wiki the main ideas and goals are described whereas at the bottom level there are scripts, tables and raw data. The structure suggested by the different levels supports a common understanding of the need to record information and of which information to record. All levels can rapidly be accessed by following hyperlinks in the wiki. Combining information into new wiki pages is also very easy in this framework. Copyright © 2010 John Wiley & Sons, Ltd.
Ruthenium‐Catalyzed Alkylation of Indoles with Tertiary Amines by Oxidation of a sp3 CH Bond and Lewis Acid Catalysis
Authors: Wang Ming‐Zhong , Zhou Cong‐Ying , Wong Man‐Kin , Che Chi‐Ming
Published: April 2010

Ruthenium porphyrins (particularly [Ru(2,6‐Cl2tpp)CO]; tpp=tetraphenylporphinato) and RuCl3 can act as oxidation and/or Lewis acid catalysts for direct C‐3 alkylation of indoles, giving the desired products in high yields (up to 82 % based on 60–95 % substrate conversions). These ruthenium compounds catalyze oxidative coupling reactions of a wide variety of anilines and indoles bearing electron‐withdrawing or electron‐donating substituents with high regioselectivity when using tBuOOH as an oxidant, resulting in the alkylation of N‐arylindoles to 3‐{[(N‐aryl‐N‐alkyl)amino]methyl}indoles (yield: up to 82 %, conversion: up to 95 %) and the alkylation of N‐alkyl or N‐H indoles to 3‐[p‐(dialkylamino)benzyl]indoles (yield: up to 73 %, conversion: up to 92 %). A tentative reaction mechanism involving two pathways is proposed: an iminium ion intermediate may be generated by oxidation of an sp3 CH bond of the alkylated aniline by an oxoruthenium species; this iminium ion could then either be trapped by an N‐arylindole (pathway A) or converted to formaldehyde, allowing a subsequent three‐component coupling reaction of the in situ generated formaldehyde with an N‐alkylindole and an aniline in the presence of a Lewis acid catalyst (pathway B). The results of deuterium‐labeling experiments are consistent with the alkylation of N‐alkylindoles via pathway B. The relative reaction rates of [Ru(2,6‐Cl2tpp)CO]‐catalyzed oxidative coupling reactions of 4‐X‐substituted N,N‐dimethylanilines with N‐phenylindole (using tBuOOH as oxidant), determined through competition experiments, correlate linearly with the substituent constants σ (R2=0.989), giving a ρ value of −1.09. This ρ value and the magnitudes of the intra‐ and intermolecular deuterium isotope effects (kH/kD) suggest that electron transfer most likely occurs during the initial stage of the oxidation of 4‐X‐substituted N,N‐dimethylanilines. Ruthenium‐catalyzed three‐component reaction of N‐alkyl/N‐H indoles, paraformaldehyde, and anilines gave 3‐[p‐(dialkylamino)benzyl]indoles in up to 82 % yield (conversion: up to 95 %).
Nitrocyanamide‐Based Ionic Liquids and Their Potential Applications as Hypergolic Fuels
Authors: He Ling , Tao Guo‐Hong , Parrish Damon A. , Shreeve Jean'ne M.
Published: April 2010

Nitrocyanamide ionic liquids with substituted imidazolium, guanidinium, and tetrazolium cations have been synthesized and fully characterized. Aminoguanidinium nitrocyanamide (7) crystallizes in the triclinic system P$\bar 1$. The results obtained from theoretical calculations based on 7 are consistent with the single‐crystal structure data. These ionic liquids exhibit desirable physicochemical properties, such as low melting points and good thermal stabilities. Furthermore, they are all impact insensitive materials. Their energetic performances, including heats of formation, detonation pressures, and detonation velocities, were studied by a combination of theoretical and empirical calculations. The ionic liquids 1–4 have large liquid ranges and low viscosities. They were shown to be promising candidates as hypergolic ionic liquids through the combustion tests with 100 % HNO3.
Kinetic Control in the Chiral Recognition of Three‐Bladed Propellers
Authors: Bonnot Clément , Aubert Emmanuel , Banerji Natalie , Lacour Jérôme , Espinosa Enrique , Chambron Jean‐Claude
Published: April 2010

The ion pair of the stereolabile C3‐symmetric, i+o proton complex [1⋅H]+ of diaza‐macropentacycle 1 and the configurationally stable Δ‐TRISPHAT ([Δ‐3]−) anion exists in the form of two diastereomers, namely, [Δ‐(1⋅H)][Δ‐3] and [Λ‐(1⋅H)][Δ‐3], the ratio of which, in terms of diastereomeric excess (de) decreases in the order [D8]THF (28 %)>CD2Cl2 (22 %)>CDCl3 (20 %)>[D8]toluene (16 %)>C6D6 (7 %)>[D6]acetone (0 %) at thermodynamic equilibrium. Except in the case of [D6]acetone, the latter is reached after a period of time that increases from 1 h ([D8]THF) to 24 h (CDCl3). Moreover, the initial value of the de of [1⋅H][Δ‐3] in CDCl3, before the thermodynamic equilibrium is reached, depends on the solvent in which the sample has been previously equilibrated (sample “history”). This property has been used to show that the crystals of [1⋅H][Δ‐3] formed by slow evaporation of CH2Cl2/CH3OH mixtures had 100 % de, which indicates that [1⋅H][Δ‐3] has enjoyed a crystallization‐induced asymmetric transformation. Structural studies in solution (NMR spectroscopy) and in the gas phase by calculations at the semiempirical PM6 level of theory suggest that the optically active anion is docked on the i+ (endo) external side of the proton complex such that one of the aromatic rings of [Δ‐3]− is inserted into a groove of [1⋅H]+, a second aromatic ring being placed astride the outside i+ pocket. Solvent polarity controls the thermodynamics of inversion of the [1⋅H]+ propeller. However, both polarity and basicity control its kinetics. Therefore, the rate‐limiting steps correspond to the ion‐pair separation/recombination and [1⋅H]+/1 deprotonation/protonation processes, rather than the inversion of [1⋅H]+, the latter being likely to take place in the deprotonated form (1).
Metal Ions Drive Thermodynamics and Photochemistry of the Bis(styryl) Macrocyclic Tweezer
Authors: Tulyakova Elena V. , Vermeersch Gaston , Gulakova Elena N. , Fedorova Olga A. , Fedorov Yuri V. , Micheau Jean Claude , Delbaere Stéphanie
Published: April 2010

UV/Vis and NMR spectroscopy were used for the structural elucidation and thermodynamic and photochemical studies of the metal‐coordinated crown‐containing macrocyclic tweezer (E,E)‐1. The bis(styryl) tweezer (E,E)‐1 formed two types of complexes with magnesium(II): a 1:1 intramolecular asymmetric sandwich complex [(E,E)‐1]⋅Mg2+ and a 1:2 complex [(E,E)‐1]⋅(Mg2+)2. In the former case, there is direct cation intramolecular exchange (0.299 s−1, ΔG≠=69.4 kJ mol−1) between two parts of the bis(styryl) tweezer (E,E)‐1. Addition of barium(II) to the bis(styryl) tweezer (E,E)‐1 led to an intramolecular centrosymmetric sandwich 1:1 complex [(E,E)‐1]⋅Ba2+. Irradiation of [(E,E)‐1]⋅Ba2+ afforded reversible intramolecular [2π+2π] photocyclization with excellent stereoselectivity and quantitative yield. In contrast, irradiation of [(E,E)‐1]⋅(Mg2+)2 resulted in reversible stepwise E,Z‐isomerization.