bluuebunny/crossref_metadata_2025 huggingface dataset:
Biodegradation of hazardous triphenylmethane dye methyl violet by Rhizobium radiobacter (MTCC 8161)
Authors: Parshetti Ganesh , Saratale Ganesh , Telke Amar , Govindwar Sanjay
Published: March 2009

Rhizobium radiobacter MTCC 8161 completely decolorized methyl violet (10 mg l–1) within 8 h both at static and shaking conditions. The decolorization time increased with increasing dye concentration. The effect of different carbon and nitrogen sources on the decolorization of methyl violet was studied. The maximum decolorization was observed in the presence of sucrose (1%) and urea (1%). UV‐Visible, HPLC and FTIR analysis of extracted products confirmed biodegradation of methyl violet. The significant increase in the activities of lignin peroxidase and aminopyrine N‐demethylase in the cells obtained after decolorization indicated involvement of these enzymes in the decolorization process. In addition to methyl violet, this strain also shows an ability to decolorize various industrial dyes, (red HE7B, yellow 4G, blue 2B, navy blue HE22, red M5B and red HE3B). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Responses of Candida fukuyamaensis RCL‐3 and Rhodotorula mucilaginosa RCL‐11 to copper stress
Authors: Villegas Liliana B. , Amoroso María J. , de Figueroa Lucía I. C.
Published: March 2009

The effect of high Cu(II) concentrations on superoxide dismutase (SOD) and catalase (CAT) activity in Candida fukuyamaensis RCL‐3 and Rhodotorula mucilaginosa RCL‐11, previously isolated from a copper filter at a mine plant in Argentina, was studied. Addition of 0.1, 0.2 and 0.5 mM Cu(II) to the culture medium increased total SOD and CAT activity in both strains. Native polyacrylamide gel electrophoresis revealed two bands with SOD activity for C. fukuyamaensis RCL‐3 and only one for R. mucilaginosa RCL‐11; the three bands corresponded to MnSOD.

Intracellular accumulation of copper and morphological changes was observed using electron microscopy. Dark bodies examined with transmission electron microscopy (TEM) after 48 h of incubation probably corresponded to copper deposits. The number of dark bodies in R. mucilaginosa RCL‐11 grew with increasing incubation time, whereas in C. fukuyamaensis RCL‐3 the amount decreased. Scanning electron micrographs (SEM) of C. fukuyamaensis RCL‐3 did not reveal any differences compared with the control, but R. mucilaginosa RCL‐11 cells were bigger than control ones. TEM confirmed absence of compartmentalization mechanisms in Cu(II) detoxification since electron‐dense bodies were mainly found in the cytoplasm. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evidence of methanesulfonate utilizers in the Sargasso Sea metagenome
Authors: Leitão Elsa , Moradas‐Ferreira Pedro , De Marco Paolo
Published: March 2009

Methanesulfonate (MSA) is one of the products of the photo‐oxidation of dimethylsulfide in the atmosphere. The genes responsible for the import of MSA into the cell (msm EFGH) and for its oxidation to formaldehyde (msm ABCD) have been previously sequenced from the soil bacterium Methylosulfonomonas methylovora str. M2 while genes for an MSA monooxygenase have been sequenced from marine bacterium Marinosulfonomonas methylotropha str. TR3. We performed a sequence‐based screening of the Sargasso Sea metagenome for homologues of the MSA monooxygenase (MSAMO) and MSA import genes. Our search retrieved one scaffold bearing genes with high identity to the msm ABCD cluster plus two scaffolds bearing genes highly identical to the msm EFGH operon. We increased the available data by sequencing two metagenome plasmids, which revealed more msm genes. In these three cases synteny with the original msm operons was revealed. We also retrieved several singletons showing high identity to shorter segments of the msm clusters or individual msm genes. Furthermore, a characteristic 26‐aa internal spacer of the MsmA Rieske‐type motif was conserved. Our findings support the case for a significant role of MSA degraders in the marine sulfur cycle and seem to suggest that they may be prominent members of the methylotrophic community in surface ocean waters. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Demonstration of the absence of intervening sequences within 23S rRNA genes from Campylobacter lari
Authors: Tazumi Akihiro , Kakinuma Yuki , Moore John E. , Millar Cherie B. , Taneike Ikue , Matsuda Motoo
Published: March 2009

Cloning, sequencing and characterization of nearly full‐length 23S rRNA genes in 12 urease‐positive thermophilic Campylobacter (UPTC) isolates were carried out using two novel PCR primer pairs. Nucleotide sequences of the 23S rRNA genes from the 12 isolates were first shown not to carry any intervening sequences (IVSs) in both the 25 and 45 helix regions. Then, two PCR primer sets were designed in silico for amplification of the helix 25 and 45 regions within 23S rRNA gene sequences from Campylobacter lari. No IVSs were identified within the 23S rRNA genes among a total of 53 isolates of C. lari, following PCR amplification, TA cloning and sequencing procedures. Intact 23S rRNA was identified in all 65 C. lari isolates, resulting in no production of the fragmented 23S rRNA. These data suggest that C. lari may not have any opportunity to interact with any other source of IVSs until now, or has been unable to integrate IVSs into their own genomes. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Direct analysis of sulfate reducing bacterial communities in gas hydrate‐impacted marine sediments by PCR–DGGE
Authors: Bagwell Christopher E. , Formolo Michael , Ye Qi , Yeager Chris M. , Lyons Timothy W. , Zhang Chuanlun L.
Published: March 2009

Molecular investigations of the sulfate reducing bacteria that target the dissimilatory sulfite‐reductase subunit A gene (dsr A) are plagued by the nonspecific performance of conventional PCR primers. Here we describe the incorporation of the FailSafe™ PCR System to optimize environmental analysis of dsr A by PCR amplification and denaturing gradient gel electrophoresis. PCR–DGGE analysis of dsr A composition revealed that SRB diversity was greater and more variable throughout the vertical profile of a marine sediment core obtained from a gas hydrate site (GC234) in the Gulf of Mexico than in a sediment core collected from a nearby site devoid of gas hydrates (NBP). Depth profiled dsr B abundance corresponded with sulfate reduction rates at both sites, though measurements were higher at GC234. This study exemplifies the numerical and functional importance of sulfate reducing bacteria in deep‐sea sedimentary environments, and incremental methodological advancements, as described herein, will continue to streamline the analysis of sulfate reducer communities in situ. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A calcium binding protein from cell wall of Neurospora crassa
Authors: Sowjanya Thommandru Naga , Mohan Pamarthi Maruthi
Published: March 2009

Isolated cell wall preparations of N. crassa bind significant levels of Ca, Mg and other divalent cations. Enzymatic treatment of the cell wall with β‐(1,3)‐glucanase, but not with chitinase, resulted in solubilization of only the calcium‐binding protein fraction. A calcium‐binding protein (CaBP) was purified by metal‐chelate affinity chromatography and reversed phase HPLC. CaBP has an Mr of around 6 kDa on SDS‐PAGE and mass spectrometry showed that it has a molecular mass of 5744 Da. One mole of CaBP binds 2 moles of calcium and is partially inhibited (15–50%) by other divalent cations (Mg, Ni and Cu). Quenching of tryptophan fluorescence was observed upon copper binding but not calcium binding. This is a first report of a calcium binding protein from the cell wall of fungi. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carbon dioxide enrichment by composting in greenhouses and its effect on vegetable production
Authors: Jin Chongwei , Du Shaoting , Wang Yue , Condon Jason , Lin Xianyong , Zhang Yongsong
Published: March 2009

Concentrations of CO2 are commonly suboptimal for plant production in greenhouses. Here, a new strategy using crop‐residues and animal‐manure composting (CRAM) was developed to increase CO2 concentration throughout the day. During the whole cultivation period, CRAM‐treated greenhouses had CO2 concentrations that were more than twice that of the control greenhouses. This resulted in yields of celery (Apium graveolens L.), leaf lettuce (Lactuca virosa L.), stem lettuce (Lactuca saiva L.), oily sowthistle (Sonchus oleraceus L.), and Chinese cabbage (Brassica chinensis L.) that were 270%, 257%, 87%, 140%, and 227% higher than those in control greenhouses, respectively. The effect of CRAM on vegetable‐quality parameters was also examined. Nitrate concentrations deceased in celery, leaf lettuce, oily sowthistle, and Chinese cabbage by 8%, 36%, 30%, and 20%, respectively. The concentrations of soluble sugars in oily sowthistle and Chinese cabbage were significantly increased by the composting procedure. In addition, the ascorbic acid concentrations increased in all five species, with average increases of 13%, 39%, 25%, 72%, and 37% for celery, leaf lettuce, stem lettuce, oily sowthistle, and Chinese cabbage, respectively. It is concluded that CO2 fertilization using CRAM in greenhouses increases yields and improves quality of common vegetables.
Direct dynamic study on the hydrogen abstraction reaction of H2CO with NCO
Authors: Sun Hao , Huang Xu‐Ri , Pan Xiu‐Mei , Wang Rong‐Shun , Sun Chia‐Chung
Published: March 2009

A direct ab initio dynamics method is used to investigate the hydrogen‐abstraction reaction of H2CO with NCO. The potential energy surface information is obtained at the MP2/6‐311G(d,p) level. More accurate single‐point energy is refined at the G3(MP2)//MP2/6‐311G(d,p) level. Furthermore, the rate constants of reaction H2CO + NCO are evaluated by using the canonical variational transition state theory with small‐curvature tunneling contributions over a wide temperature range of 200–2000 K. The calculated reaction enthalpy and rate constants are in good agreement with the available experimental values. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 394–400, 2009
Intrathecal morphine combined with intravenous patient-controlled analgesia is an effective and safe method for immediate postoperative pain control in live liver donors
Authors: Ko Justin Sangwook , Choi Soo Joo , Gwak Mi Sook , Kim Gaab Soo , Ahn Hyun Joo , Kim Jie Ae , Hahm Tae Soo , Cho Hyun Sung , Kim Kyoung Mi , Joh Jae Won
Published: March 2009

The healthy condition of living donors makes their tolerance to pain particularly low, and clinicians are often challenged to come up with an analgesic technique that is effective yet ensures donor safety. This study compared, in donor right hepatectomy, the efficacy and safety of preoperative intrathecal morphine (ITM) combined with intravenous patient-controlled analgesia (IV-PCA) with IV-PCA alone. Forty adult patients were randomly allocated into 2 groups: ITM+IV-PCA group (n = 20) and IV-PCA-only group (n = 20). Patients in the ITM+IV-PCA group received morphine sulfate (400 μg). The visual analog scale (VAS) at rest and when coughing and supplementary meperidine and IV-PCA (fentanyl) consumption were assessed at 2, 4, 6, 8, 10, 12, 18, 24, 30, 36, 42, 48 56, 64, and 72 hours after surgery. Also, side effects such as sedation, dizziness, nausea, vomiting, pruritus, and respiratory depression were evaluated. The ITM+IV-PCA group showed significantly less pain at rest and when coughing for up to 30 hours and 24 hours, respectively. Cumulative postoperative consumption of meperidine and IV-PCA (fentanyl) were significantly less in the ITM+IV-PCA group. The incidence of side effects were comparable between the 2 groups except for pruritus; its incidence was significantly higher in the ITM+IV-PCA group during the first 24 hours, but no treatment was required due to its mild severity. The results of our study suggest that preoperative ITM combined with IV-PCA may be considered as an effective and safe pain management regimen in living liver donors who have characteristics of low tolerance to pain and postoperative coagulation derangement.
Twenty years' follow-up of portal vein conduits in liver transplantation
Authors: Nikitin Dmitriy , Jennings Linda W. , Khan Tariq , Vasani Sugam , Ruiz Richard , Sanchez Edmund Q. , Chinnakotla Srinath , Levy Marlon F. , Goldstein Robert M. , Klintmalm Goran B.
Published: March 2009

Portal vein problems remain a formidable challenge in liver transplantation. In select situations, a portal vein conduit can provide a solution. No long-term results have been reported. This study was designed to assess the impact of portal vein conduits on graft survival after liver transplantation and the safety of portal vein conduits and to establish the long-term results (up to 20 years) of portal vein conduits. Data from 2370 adult liver transplants were prospectively collected into a computerized research database and analyzed. All portal vein conduits were constructed from the donor iliac vein obtained at the liver retrieval. Portal vein conduits were required in 35 (1.5%) first transplants. The long-term (up to 20 years of follow-up) graft survival after liver transplantation using portal vein conduits was excellent and comparable to that of the control group. The graft survival was 65% with the conduit versus 66% without the conduit at 5 years of follow-up, 58% versus 51% at 10 years, and 48% versus 35% at 15 years. There was a higher rate (8.6% versus 1.4%) of portal vein thrombosis after the portal vein conduit, and the majority occurred in the first 3 months after transplantation. For the same time period, there was no statistically significant difference in graft survival or patient survival for the retransplants with and without portal vein conduits. There was no statistically significant difference in graft survival or patient survival for the transplants with portal vein conduits and with portal vein thrombendvenectomy. In conclusion, portal vein conduits can be used safely for liver transplantation with no negative impact on long-term graft survival or patient survival. Despite the higher rate of portal vein thrombosis in the immediate postoperative period, excellent long-term results can be obtained.
Endoscopic treatment for biliary stricture after adult living donor liver transplantation
Authors: Seo Jeong Kyun , Ryu Ji Kon , Lee Sang Hyub , Park Joo Kyung , Yang Ki Young , Kim Yong-Tae , Yoon Yong Bum , Lee Hae Won , Yi Nam-Joon , Suh Kyung Suk
Published: March 2009

Endoscopic intervention is considered to be the primary treatment for biliary stricture after adult living donor liver transplantation (LDLT) with duct-to-duct biliary reconstruction. The aim of this study was to investigate the risk factors of biliary stricture and the clinical outcomes and predictors of failure after endoscopic retrograde cholangiography with balloon dilation (ERC-D). We enrolled 239 adult patients who underwent LDLT between 2000 and 2006. Sixty-eight patients (28.4%) developed biliary stricture. Twenty-nine patients with anastomotic biliary stricture were treated with ERC-D and stenting. We retrospectively analyzed the risk factors of biliary stricture and the clinical outcomes of ERC-D. The median follow-up period was 31 months. The risk factors of biliary stricture on multiple logistic regression analysis were a graft with multiple bile ducts, a previous history of bile leakage, and hepatic artery stenosis. The overall success rate of ERC-D was 64.5%. On simple logistic regression, the failure of primary ERC-D was associated with late biliary stricture over 24 weeks and more than 8 weeks between a 2-fold increase of serum alkaline phosphatase from the stable level and ERC-D, even though these were not statistically significant on multiple logistic regression. The relapse rate of stricture after successful ERC-D was 30%. The duration of stenting in the recurrence group was shorter than that in the nonrecurrence group (11.8 ± 5.03 versus 29.0 ± 11.6 weeks, P = 0.004). ERC-D is effective for the management of anastomotic biliary stricture. However, the failure rate of primary ERC-D may be high in patients with late onset and delayed diagnosis of biliary stricture. The recurrence seems to occur frequently in patients with a short duration of stenting.
Modulation of invasive properties of CD133(+) glioblastoma stem cells: A role for MT1‐MMP in bioactive lysophospholipid signaling
Authors: Annabi Borhane , Lachambre Marie‐Paule , Plouffe Karine , Sartelet Hervé , Béliveau Richard
Published: March 2009

Future breakthroughs in cancer therapy must accompany targeted agents that will neutralize cancer stem cells response to circulating growth factors. Since the brain tissue microenvironmental niche is a prerequisite for expression of the stem cell marker CD133 antigen in brain tumors, we investigated the invasion mechanisms specific to CD133(+) U87 glioblastoma cells in response to lysophosphatidic acid (LPA) and sphingosine 1‐phosphate (S1P), two circulating bioactive lysophospholipids and potent inducers of cancer. A CD133(+) U87 glioma cell population was isolated from parental U87 glioblastoma cells using magnetic cell sorting technology. The CD133(+)‐enriched cell population grew as neurospheres and showed enhanced maximal response to both LPA (∼5.0‐fold) and S1P (∼2.5‐fold) at 1 µM when compared to parental U87 cells. The increased response to LPA in CD133(+) cells, reflected by increased levels of phosphorylated ERK, was found independent of the cooperative functions of the membrane‐type‐1 matrix metalloproteinase (MT1‐MMP), while this cooperativity was essential to the S1P response. Quantitative RT‐PCR was performed and we found higher gene expression levels of the S1P receptors S1P1 and S1P2, and of the LPA receptor LPA1 in CD133(+) cells than in their parental U87 cells. These increased levels reflected those observed from in vivo experimental U87 tumor implants. Our data suggest that the CD133(+) cell subpopulation evokes most of the lysophospholipid response within brain tumors through a combined regulation of S1P/LPA cell surface receptors signaling and by MT1‐MMP. The emergence of lead compounds targeting the stem cell niche and S1P/LPA signaling in CD133(+) cancer cells is warranted. © 2009 Wiley‐Liss, Inc.
Influence of feeding strategies of mixed microbial cultures on the chemical composition and microstructure of copolyesters P(3HB‐co‐3HV) analyzed by NMR and statistical analysis
Authors: Ivanova G. , Serafim L. S. , Lemos P. C. , Ramos A. M. , Reis M. A. M. , Cabrita E. J.
Published: March 2009

NMR spectroscopy was applied for quantitative and qualitative characterization of the chemical composition and microstructure of a series of poly(3‐hydroxybutyrate‐co‐3‐hydoxyvalerate) copolymers, P(3HB‐co‐3HV), synthesized by mixed microbial cultures at several different feeding strategies. The monomer sequence distribution of the bacterially synthesized P(3HB‐co‐3HV) was defined by analysis of their high‐resolution 1D 13C NMR and 2D 1H/13C HSQC and 1H/13C HMBC NMR spectra. The results were verified by employment of statistical methods and suggest a block copolymer microstructure of the P(3HB‐co‐3HV) copolymers studied. Definitive distinction between block copolymers or a mixture of random copolymers could not be achieved. NMR spectral analysis indicates that the chemical composition and microstructure of the copolymers can be tuned by choosing a correct feeding strategy. Copyright © 2009 John Wiley & Sons, Ltd.
Contrast‐enhanced MR angiography using time resolved interleaved projection sampling with three‐dimensional cartesian phase and slice encoding (TRIPPS)
Authors: Du Jiang
Published: March 2009

Undersampled projection reconstruction (PR) techniques provide contrast enhanced MR angiography (CE‐MRA) with high temporal resolution, but sensitivity to eddy current, gradient error and off‐resonance effects. It is desirable to combine the time efficiency of undersampled PR acquisition with the robustness of Cartesian imaging. In this work we present a technique designed to do this termed time resolved projection sampling with three‐dimensional (3D) Cartesian phase and slice encoding (TRIPPS), where 3D Cartesian k‐space is partitioned into multiple half projections in the ky‐kz plane. The phase and slice encoding are performed along predefined center‐out radial trajectories. The whole set of half projections is interleaved into multiple groups of half projections, with each group sparsely but uniformly covering the ky‐kz space. A view sharing sliding window reconstruction algorithm is adapted to reconstruct the dynamic images. The feasibility of the TRIPPS technique for CE‐MRA was demonstrated on the renal, pulmonary, and intracranial vasculatures of healthy volunteers with a high temporal resolution of 2 s/frame. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Modification of rat detrusor muscle contraction by ascorbic acid and citric acid involving enhanced neurotransmitter release and Ca2+influx
Authors: Dasgupta Jaydip , Elliott Ruth A. , Tincello Douglas G.
Published: March 2009

Aims

Consumption of carbonated soft drinks is independently associated with the development of overactive bladder (OR 1.41, 95% Cl 1.02–1.95). We have shown previously that artificial sweeteners, present in carbonated soft drinks, enhanced detrusor muscle contraction. Other constituents of soft drinks are preservatives and antioxidants, we evaluated the effects of two of these, ascorbic acid and citric acid, on the contractile response of isolated rat bladder muscle strips.

Methods

Detrusor muscle strips were suspended in a perfusion organ bath. We determined the effect of ascorbic acid and citric acid on the contractile responses to electrical field stimulation (EFS) in the absence and presence of atropine, carbachol, α, β methylene ATP, potassium and calcium.

Results

Ascorbic acid and citric acid (10−7M to 10−3M) enhanced the contractile response to 10 Hz EFS compared to control (P < 0.01). The frequency and amplitude of spontaneous bladder contractions were enhanced in the presence of ascorbic acid and citric acid by 14%, 21%, 21%, and 11% respectively. Ascorbic acid 10−4M significantly increased the atropine resistant response to EFS 5 Hz by 37% (P < 0.01) and inhibited contraction in response to carbachol 10−4M by 24%, (P < 0.05). Both ascorbic acid 10−4M and citric acid 10−5M significantly enhanced maximum contractile responses to α, β methylene ATP, KCI and calcium compared to control.

Conclusions

Ascorbic acid and citric acid augmented bladder muscle contraction possibly by enhanced Ca2+influx. Presynaptic neurotransmitter release was enhanced by ascorbic acid. Carbonated beverages containing preservatives may aggravate symptoms of OAB. Neurourol. Urodyn. 28:542–548, 2009. © 2009 Wiley‐Liss, Inc.
Naturally compatible: Starch acetate/cellulosic fiber composites. I. Processing and properties
Authors: Nättinen Kalle , Hyvärinen Sari , Joffe Roberts , Wallström Lennart , Madsen Bo
Published: March 2009

Composite compounds based on hemp and flax fibers in triethyl citrate plasticized starch acetate were prepared by melt processing. For better properties and processability, compounds with plasticizer contents in the range 20–35 wt% were screened. Composites were prepared with fiber contents up to 50 wt%. The composite mechanical properties were measured from injection molded test specimens. A Young's modulus of 8.3 GPa and stress at maximum load of 51 MPa were obtained with 40 wt% flax fiber in a plasticized starch acetate with 20 wt% triethyl citrate. Decreasing the plasticizer and increasing the fiber content, the tensile properties were consistently improved. An almost linear relation between fiber content and the tensile properties was found. The increase of the fiber content first improved the impact strength, but at higher fiber contents resulted in a reduction of impact strength. The quality of the produced materials was found to be good; the variation in properties between duplicated compounds was acceptable low, the variation in density and fiber content along a single tensile specimen was low, and finally, the porosity content was low even at high fiber content. The latter result was verified with scanning electron microscope images of fracture surfaces of the composites. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Production of poly(lactic acid)/organoclay nanocomposite scaffolds by microcompounding and polymer/particle leaching
Authors: Ozkoc Guralp , Kemaloglu Sebnem , Quaedflieg Martin
Published: March 2009

Organoclay reinforced poly(lactic acid) (PLA)/poly(vinyl alcohol) (PVA) blend based porous nanocomposite scaffolds are prepared by microcompounding/injection molding and subsequent polymer (PVA)/particle (NaCl) leaching method. The objective of the study is to investigate the effect of clay content on the properties of scaffolds for tissue engineering. It is revealed from X‐ray diffraction and TEM studies that incorporation of PVA to PLA matrix as a polymeric porogen enhance the state of dispersion of clay particles resulting in an exfoliated structure. The porosities of all the scaffolds are higher than 70% and the pores are well‐interconnected as observed by SEM. The addition of clay to the scaffolds improves the compressive modulus. Differential scanning calorimeter analysis shows that Tg of neat‐PLA is shifted to lower values when it is compounded with PVA. As a result, it is demonstrated that the method applied in this work can be a good candidate for production of polymeric scaffolds for tissue engineering applications. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
A comparative analysis of a modified picture frame test for characterization of woven fabrics
Authors: Milani A.S. , Nemes J.A. , Lebrun G. , Bureau M.N.
Published: March 2009

An experimental, finite‐element analysis framework is utilized to estimate the deformation state in a modified version of the picture frame test. During the analysis, the effect of fiber misalignment and the deformation heterogeneity in the tested fabric, a 2 × 2 PP/E‐Glass twill, is accounted for and a force prediction model is presented. Using an equivalent stress–strain normalization scheme, the comparison of the modified test with the conventional (original) picture frame and bias‐extension tests is also made, and results reveal similarities and differences that should receive attention in the identification of constitutive models of woven fabrics using these basic tests. Ideally, the trellising behavior should not change from one test to another but results show that in the presence of fiber misalignment, the modified picture frame test yields a behavior closer to that of the bias‐extension test, while the general form of the test's repeatability, measured by a signal‐to‐noise metric, remains similar to the original picture frame test. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Opening the white boxes: the licensing documentation of efficacy and safety of psychotropic medicines for children
Authors: Aagaard Lise , Thirstrup Steffen , Hansen Ebba Holme
Published: March 2009

Purpose

The objective of the present study was to explore the available evidence in a regulatory agency on the safety and efficacy of two types of psychotropic medicine frequently prescribed to children and adolescents.

Methods

We analysed the documentation in registration files, renewal registration files, summaries of product characteristics and scientific assessment reports in the Danish Medicines Agency for two psychotropic medications prescribed for children: methylphenidate and citalopram to discover what data pertaining to the pediatric population are available to the regulatory agency.

Results

The licensing of methylphenidate for treating attention‐deficit hyperactivity disorders (ADHD) in children from the age of six was based on a single‐dose crossover study and, a 2‐week double blind, parallel group clinical trial in 100 patients from ages 6 to 12 and published literature. Citalopram is not licensed for pediatric use in Denmark. Citalopram was being investigated in three ongoing clinical trials lasting 8–24 weeks in 423 patients aged 7–18 years. The registration files contained no data on the long‐term efficacy and safety of citalopram in pediatric use. Registration material also contained information on planned clinical trials with methylphenidate and citalopram among children/adolescents.

Conclusions

Evidence on the efficacy and safety of methylphenidate and citalopram for pediatric use in the Danish Medicine Agency is limited and supports the need for further clinical trials. Medicine prescription for the pediatric population should be monitored in order to identify risks that were not identified at the time of licensing. The results of clinical trials already conducted should be made publicly available. Copyright © 2009 John Wiley & Sons, Ltd.
Effect of microstructure on crazing onset in polyethylene under tension
Authors: Addiego Frédéric , Dahoun Abdesselam , G'Sell Christian , Hiver Jean‐Marie , Godard Olivier
Published: March 2009

The influence of microstructure on dilatation onset is analyzed in polyethylene (PE) under tension. Tests are performed by means of a video‐controlled testing system that gives access to true stress σ33—true strain ε33 curve and records volume strain εv during stretching. The results indicate that the strain ε (and the corresponding stress σ) from which viscoplastic dilatation begins depends on microstructural properties of PE. At microscopic scale, materials having a low ε are characterized by inhomogeneous deformation mechanisms leading to pronounced crazing phenomena in amorphous layers. On the contrary, materials having a high ε involve homogeneous deformation mechanisms that limit crazing. These observations are discussed on the basis of crystallinity and tie molecules density. A simple model predicting ε is developed from these microstructural aspects. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
The path to 25% silicon solar cell efficiency: History of silicon cell evolution
Authors: Green Martin A.
Published: March 2009

The first silicon solar cell was reported in 1941 and had less than 1% energy conversion efficiency compared to the 25% efficiency milestone reported in this paper. Standardisation of past measurements shows there has been a 57% improvement between confirmed results in 1983 and the present result. The features of the cell structure responsible for the most recent performance increase are described and the history of crystalline and multicrystalline silicon cell efficiency evolution is documented. Copyright © 2009 John Wiley & Sons, Ltd.
2‐D DIGE analysis of Senegalese sole (Solea senegalensis) testis proteome in wild‐caught and hormone‐treated F1 fish
Authors: Forné Ignasi , Agulleiro María J. , Asensio Esther , Abián Joaquín , Cerdà Joan
Published: March 2009

In the farmed flatfish Senegalese sole, F1 males reared in captivity often show lower sperm production and fertilization capacity than wild‐caught males. To gain insights into the molecular mechanisms that may be altered in the F1 testis, we used 2‐D DIGE to compare the protein profiling of the testis of wild‐caught males at the spermiation stage with that of F1 males showing different stages of germ cell development after hormone treatment in vivo. The abundance of 58 out of 1014 protein spots was found to differ significantly between the groups. De novo identification of these proteins by MS/MS revealed that proteins implicated in oxidoreductase activity, protein catabolism, formation of the zona pellucida receptor, cytoskeleton organization, and lipid binding and metabolism, were regulated in the F1 testes as germ cell development progressed. However, distinct isoforms or PTMs of some of these proteins, as well as of proteins involved in iron and glucose metabolism and ATP production, were expressed at lower levels in the testes of F1 males than in wild fish regardless of the hormone treatment. These results contribute to identifying proteins associated with spermatogenesis not previously described in teleosts, and suggest potential mechanisms that may be involved in the poor reproductive performance of Senegalese sole F1 males.
The two‐phase partitioning system – a powerful technique to purify integral membrane proteins of Corynebacterium glutamicum for quantitative shotgun analysis
Authors: Fränzel Benjamin , Fischer Frank , Trötschel Christian , Poetsch Ansgar , Wolters Dirk
Published: March 2009

We established a single consecutive strategy which assigned the most comprehensive number of integral membrane proteins from Gram‐positive bacteria to date. For this purpose, we adapted a biphasic partitioning system for the biotechnologically intensively used Corynebacterium glutamicum and proved for the first time that such a system is well suited for quantitative comparison. 297 integral membrane proteins were identified by our integrated approach, which depletes stringently cytosolic proteins. In combination with our previously developed SIMPLE strategy, our data comprise 61% (374 integral membrane proteins) of the entire membrane proteome, which aims towards an almost comprehensive coverage. Wild type and a production strain of C. glutamicum were compared by 15N metabolic labelling and quantitation was obtained by spectral counting and peak areas. Both quantification strategies display a consistent trend in up or downregulation of proteins. Nevertheless, spectral counting often provides results indicating a much stronger regulation compared to ProRata values. Either spectral counting seems to exaggerate protein regulation or ProRata tends to attenuate the information about the regulation level. We highlight some of the biologically relevant candidates, which prove that our approach helps to give a deeper quantitative insight towards the understanding of transport and other membrane associated processes, important for strain development of C. glutamicum.
Ethylene polymerization behavior of Cr(III)‐containing montmorillonite: Influence of chromium compounds
Authors: Yamamoto Kazuhiro , Ishihama Yoshiyuki , Isobe Eiji , Sugano Toshihiko
Published: March 2009

Montmorillonite was treated with Cr(NO3)3, Cr(acetate)3, and Cr(acac)3 to give three catalyst precursors, Cr‐MMT‐1, Cr‐MMT‐2, and Cr‐MMT‐3, respectively. Application of these catalysts to the ethylene polymerization reaction revealed Cr‐MMT‐1 to be much more reactive than the other two while the molecular weight distributions of the polymers were practically the same. Elemental analysis, XRD, and TEM measurements suggested that chromium occupied the interlayer section in Cr‐MMT‐1 and mostly the outer surface region for the other two catalysts. Aluminosilicate‐supported Cr catalysts exhibited reactivity similar to that of Cr‐MMT‐2 and Cr‐MMT‐3. However, more of the low‐molecular‐weight polymer was formed. These data suggested that there is a relationship between the sites of the Cr ions and catalytic reactivity, and between supporting solid identity and molecular weight distribution of the polymer. The use of n‐Bu2Mg and Et2Zn in the place of Et3Al led to lower activity but gave polymers of narrower molecular weight distribution, with more of the high‐molecular‐weight material. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2272–2280, 2009
Heterogeneous polymerization with polyaspartate macromonomer having vinyl pendant groups. II. Control of particle diameter and diameter distribution in dispersion copolymerization
Authors: Tomita Keisuke , Ono Tsutomu
Published: March 2009

To control particle diameter and particle diameter distribution in dispersion copolymerization of styrene and sodium polyaspartate macromonomer containing vinylbenzyl pendant groups, effects of some polymerization parameters, water contents, initiator concentration, styrene monomer concentration, reaction temperature, and type of initiator on the particle diameter and the diameter distribution were investigated. Variation of the water contents from 20 to 80 vol % controls the resultant particle diameter from 0.066 to 0.47 μm. The diameter increased with increasing initiator concentration. This tendency is similar to dispersion polymerization system using a nonpolymerizable stabilizer. Particle diameter distribution broadened with increasing styrene monomer concentration. This trend was attributed to the increase of a period of particle formation. This result indicated that the period of particle formation affected the resultant particle diameter distribution. Particle diameter distribution was successfully improved (CV = 9.1 from 23.6%) by shortening of decomposition time of initiator. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2281–2288, 2009
Alternatively linking fullerene and conjugated polymers
Authors: Hiorns Roger C. , Iratçabal Pierre , Bégué Didier , Khoukh Abdel , De Bettignies Rémi , Leroy Jocelyne , Firon Muriel , Sentein Carole , Martinez Hervé , Preud'homme Hugues , Dagron‐Lartigau Christine
Published: March 2009

The stereo‐electronic control over bisadditions of conjugated polymers to fullerene (C60) is explored in the formation of alternating copolymers. The chemistry, resulting configuration, and properties of poly(3‐hexylthiophene)‐alt‐C60 copolymers prepared by either classic pyrrolidine ring formation or an atom transfer radical addition are compared. Both routes result in controlled additions of polymers to C60. Extensive macromolecular modeling through PM6 methods indicate that there is no conjugation between P3HT and C60 in the systems studied. This along with 2D‐NMR, AFM, and photovoltaic characterizations of the materials indicate the importance of the structure of the modified C60 and the nature of the linking group between C60 and P3HT segments in determining the morphology of the copolymers in the solid state. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2304–2317, 2009
High Tg and high organosolubility of novel unsymmetric polyimides
Authors: Chern Yaw‐Terng , Tsai Jeng‐Yu , Wang Jane‐Jen
Published: March 2009

A series of new polyimides (PIs) containing di‐tert‐butyl side groups were synthesized via a polycondensation of 1‐(4‐aminophenoxy)‐4‐(4‐amino‐2‐methylphenyl)‐2,6‐di‐tert‐butylbenzene (3) with various aromatic tetracarboxylic dianhydrides. The novel unsymmetric PIs exhibited a low dielectric constants (2.78–3.02), low moisture absorption (0.53–1.35%), excellent solubility, and high glass transition temperature (308–450 °C). The PI derived from the new diamine and the very rigid naphthalene‐1,4,5,8‐tetracarboxylic dianhydride (NTDA) was soluble in N‐methyl‐2‐pyrrolidone, chloroform, m‐cresol, and cyclohexanone. The unsymmetric di‐tert‐butyl pendent groups significantly enhance the rotational barrier of the polymer chains; thus these PIs had high Tgs. The 1H NMR spectrum of the diamine 3 revealed that the protons of 4‐aminophenoxy moiety are not chemical shift equivalent. This is because the steric hindrance of the bulky di‐tert‐butyl groups prevents the benzene ring of 4‐aminophenoxy moiety from rotating freely. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2443–2452, 2009
Micro‐FT‐IR study of stretching a single filament: Polymorphic transition in nylon 6
Authors: Na Bing , Lv Ruihua , Tian Nana , Xu Wenfei , Li Zhujun , Fu Qiang
Published: March 2009

The polymorphic transition (γ → α conversion) in a single nylon 6 filament under stretching has been explored for the first time by using micro‐FT‐IR spectroscopy. The content of γ‐form deceases with straining while the amount of α‐form gradually increases, suggesting γ → α conversion. A two‐step mechanism, that is, melting and recrystallization, seems pertinent for the γ → α conversion considering that the γ‐form shows somewhat reversible and the α‐form keeps nearly intact upon unloading. Moreover, stress‐induced γ → α conversion at large strain can be well correlated with the molecular orientation in the amorphous phase and thus a serial arrangement between the γ crystals and amorphous phase along the stretching direction is proposed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 898–902, 2009
Characterization of poly(vinylidene fluoride)/Na+‐MMT composites: An investigation into the β‐crystalline nucleation effect of Na+‐MMT
Authors: Wu Tongfei , Xie Tingxiu , Yang Guisheng
Published: March 2009

Poly(vinylidene fluoride)(PVDF)/Na+‐MMT composites have been successfully prepared utilizing sodium montmorillonite (Na+‐MMT) via N,N‐dimethylformamide (DMF) solution mixing. The dispersion of Na+‐MMT layers in composites were investigated by transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The effect of adding Na+‐MMT on crystallization behavior of PVDF was specifically studied. The β‐crystalline nucleation effect of Na+‐MMT was investigated and confirmed by differential scanning calorimetry (DSC), XRD, and Fourier transform infrared (FTIR) results. The interaction between PVDF and the surface of Na+‐MMT layers in DMF solution was confirmed by UV‐Vis absorbency. The effect of adding Na+‐MMT on rheological and electrical properties of PVDF/Na+‐MMT composites were also determined. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 903–911, 2009
Physio‐Chemical Modifications of Polystyrene and Poly(propylene) Surfaces by Electron Beam‐Generated Plasmas Produced in Argon
Authors: Lock Evgeniya H. , Walton Scott G. , Fernsler Richard F.
Published: March 2009

Pulsed, electron beam generated plasmas produced in argon were used to modify the surfaces of polystyrene and poly(propylene). The influence of plasma parameters including duty factor, plasma period and exposure time on the surface chemistry, energy and morphology was investigated. In these plasmas, the energy of ions striking the surfaces was modest (≤ 5 eV) and comparable to the bond strength of most polymers. Despite the lack of reactive species in the background, a substantial modification in the chemical composition of the polymer surface occurred, leading to a significant increase in surface energy. These changes occurred without a significant increase in surface roughness, or loss of material due to etching. Indeed, the surface morphology of polystyrene was practically unchanged, whereas the surface of poly(propylene) became smoother with plasma exposure. Based on theoretical estimations, the ions play major role in the modification of polymers.

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Thermal Initiation of Non‐Electric Detonators
Authors: Zucker Jonathan M. , Dickson Peter , Sanders V. Eric
Published: March 2009

Cookoff – the concept of heating explosives to ignition – is a useful tool for determining issues that may be related to safely using and storing explosives, and as such, cookoff experiments have been performed on many different materials. All explosive systems require a means of initiation, which is usually a detonator: a device that often contains a sensitive, primary explosive and a more powerful, secondary explosive. Even if the cookoff behaviors of all the individual explosives in an explosive system are known, the behavior of the combined system may be quite different. In this experiment, the cookoff behavior of non‐electric detonators is investigated. It was determined that there was no distinguishable difference between initiating detonators properly or heating them at a rate greater than 10 °C min−1. Heating detonators at rates less than 10 °C min−1 diminished their output.
Hole–polar phonon interaction scattering mobility in chain structured TlSe0.75S0.25 crystals
Authors: Qasrawi A. F. , Gasanly N. M.
Published: March 2009

In this study, the electrical resistivity, charge carriers density and Hall mobility of chain structured TlSe0.75S0.25 crystal have been measured and analyzed to establish the dominant scattering mechanism in crystal. The data analyses have shown that this crystal exhibits an extrinsic p‐type conduction. The temperature‐dependent dark electrical resistivity analysis reflected the existence of three energy levels located at 280 meV, 68 meV and 48 meV. The temperature dependence of carrier density was analyzed by using the single donor–single acceptor model. The carrier concentration data were best reproduced assuming the existence of an acceptor impurity level being located at 68 meV consistent with that observed from resistivity measurement. The model allowed the determination of the hole effective mass and the acceptor–donor concentration difference as 0.44m0 and 2.2 × 1012 cm–3, respectively. The Hall mobility of the TlSe0.75S0.25 crystal is found to be limited by the scattering of charged carriers over the (chain) boundaries and the scattering of hole–polar phonon interactions above and below 300 K, respectively. The value of the energy barrier height at the chain boundaries was found to be 261 meV. The polar phonon scattering mobility revealed the high‐frequency and static dielectric constants of 13.6 and 15.0, respectively. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Beyond the AlGaN/GaN HEMT: new concepts for high‐speed transistors
Authors: Palacios Tomas
Published: March 2009

Solid state power amplifiers operating at mm‐ and sub‐mm‐wave frequencies are key components of numerous communication, sensors and defense systems. Nitride semiconductors have the potential to provide unprecedented levels of power at these frequencies. However, a multidimensional design and optimization is required to achieve acceptable levels of power gain and efficiency at high frequencies. In this paper we discuss some of the main challenges to increase the operating frequency of nitride transistors. New solutions are proposed to increase the electron confinement, electron velocity and access resistances of deeply scaled devices (Abstract figure) and to unleash their great potential. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Porous silicon versus its composite with C60: testing in vitro
Authors: Kuznetsov S. N. , Volkova T. O. , Pikulev V. B. , Saren A. A. , Gardin Yu. E. , Gurtov V. A.
Published: March 2009

We have studied in vitro an efficiency of the promising photosensitizer for photodynamic therapy (PDT) on the base of porous silicon (PSi) impregnated with fullerene C60. It is shown that a low concentration addition of fullerene boosts sharply a cancer cell killing in comparison with the pristine PSi. A dark toxicity of the proposed composite drug for PDT does not exceed that for the pristine PSi as it was revealed for observation period of five days. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of humidity adsorption in porous silicon layers
Authors: Kovacs Andras , Meister Dirk , Mescheder Ulrich
Published: March 2009

The dependence of humidity adsorption in porous silicon (PS) layers on the fabrication conditions (current density and oxidation) has been investigated. As‐prepared and additionally oxidized PS layers have been investigated using physical gas (N2) adsorption measurement at 77 K, water vapor adsorption measurements at room temperature, impedance spectroscopy and contact angle measurement. Pore size distributions and specific surface areas have been calculated using the BJH and BET model. Additional oxidation of porous layer promotes the humidity adsorption and improves the wetting compared to as‐fabricated porous Si layers. The correlation between adsorption isotherms, electrical parameters and surface effects are presented and discussed in respect to the use of PS for humidity sensing. Oxidation of PS layers improves the sensitivity of PS based humidity sensors considerably. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)