bluuebunny/crossref_metadata_2025_split huggingface dataset:
What's in a name? Qualitative description revisited
Authors: Sandelowski Margarete 
Published: December 2009

Abstract“Whatever Happened to Qualitative Description?” (Sandelowski, 2000) was written to critique the prevailing tendency in qualitative health research to claim the use of methods that were not actually used and to clarify a methodological approach rarely identified as a distinctive method. The article has generated several misconceptions, most notably that qualitative description requires no interpretation of data. At the root of these misconceptions is the persistent challenge of defining qualitative research methods. Qualitative description is a “distributed residual category” (Bowker & Star, 2000). Cambridge, MA: The MIT Press) in the classification of these methods. Its value lies not only in the knowledge its use can produce, but also as a vehicle for presenting and treating research methods as living entities that resist simple classification. © 2009 Wiley Periodicals, Inc. Res Nurs Health 33:77–84, 2010
Electrically and thermally modulated optical properties of polymer dispersed chiral liquid crystal
Authors: Zhang B.Y. , Wang J.H. , Xu X.Y. , Xi M. 
Published: December 2009

AbstractThe polymer dispersed chiral liquid crystals (PDCLCs) film was fabricated by photopolymerization induced phase separation (PIPS) of chiral liquid crystal (CLC)/polymerizable monomers/photoinitiator composites. The effects of the electrical and thermal modulation on optical rotation properties of PDCLCs film were investigated. The microsized liquid crystal droplets were resulted from the rapid polymerization of trifunctional monomers. The effects of the electrically and thermally modulated on realignment of liquid crystal director were investigated. It was found that the intensity of electric and thermal field influenced the alignment of liquid crystal droplets' director on PDCLCs film, and the electro‐optical properties of the composites were affected accordingly. The principle of free energy minimum was used for explaining the change of optical rotation and transmittance of PDCLCs film with applying the voltage to the film. The dispersion and sizes of liquid crystal droplets were described by polarizing optical microscope (POM). POLYM. COMPOS., 31:1535–1540, 2010. © 2009 Society of Plastics Engineers
An investigation of the mechanical behavior of carbon epoxy cross ply cruciform specimens under biaxial loading
Authors: Makris Andreas , Ramault Carla , Van Hemelrijck Danny , Zarouchas Dimitrios , Lamkanfi Ebrahim , Van Paepegem Wim 
Published: December 2009

AbstractIn this study, carbon epoxy cruciform type specimens with a cross‐ply layup were biaxially and uniaxially in‐plane loaded using four independent servo‐hydraulic actuators. Four different biaxial loading ratios were investigated when the applied load was quasi‐static. A comparison between experimental observations (for the damage and strain evolution of the biaxially loaded central section of the specimen) coming from digital image correlation measurements and a 3D finite element damage model will be shown. The symmetry and the uniformity of the strain field on the biaxially loaded zone were by the use of digital image correlation measurements investigated. Furthermore, the failure loads coming from the load cells of the machine were straightforward compared with the output of the finite element damage model. POLYM. COMPOS., 31:1554–1561, 2010. © 2009 Society of Plastics Engineers
Void formation model and measuring method of void formation condition during hot pressing process
Authors: Gu Yizhuo , Li Min , Zhang Zuoguang , Sun Zhijie 
Published: December 2009

AbstractFor resin matrix composites, voids are common defects that can seriously deteriorate the properties of the composite parts. Thus, the elimination of voids is a crucial element in controlling the manufacturing process of composite parts. This article focuses on void formation originating from hygroscopic water for resin matrix composite laminates prepared with hot pressing process. The Kardos void formation model was developed to analyze the critical resin pressure for the initiation of voids, and the influencing factors were investigated experimentally to validate the modified model. It is found that resin pressure and gel temperature are the two key parameters to control void defects and that entrapped air in prepreg stacks must be considered in the void formation model. Furthermore, a simple method was established to measure the relationship between porosity and the processing parameters, and the void formation conditions of the resin and the prepreg stack were also studied. The theoretically predicted void formation conditions and the experimental results were compatible for the studied cases. These results are valuable for eliminating void defects, optimizing processing parameters, and enhancing the performance of composite parts. POLYM. COMPOS., 31:1562–1571, 2010. © 2009 Society of Plastics Engineers
Nanometer‐thick patterned conductive films prepared through the self‐synthesis of polythiophene derivatives
Authors: Liu Cheng‐Dar , Huang Chih‐Kai , Wu Sheng‐Yen , Han Jin‐Lin , Hsieh Kuo‐Huang 
Published: December 2009

AbstractThe development of flexible electronics requires the patterning of conductive and active semiconductor films. Although inorganic materials such as indium tin oxide and metal nanoparticles have high conductivity and transparency, their poor interfacial adhesion with organic layers, lack of flexibility, high weight and high capital costs are drawbacks. In contrast, organic conducting polymers have great potential for use in commercial flexible electronic applications because of their low production costs, environmental stability and acceptable conductivities. A UV‐curable photoresist containing hydroxyl groups was prepared from a mixture of a photoinitiator, epoxy‐acrylate resin, hydroxyethyl methacrylate and tripropylene glycol diacrylate. Patterns having line widths/spaces of 100/100 µm and 10/5 µm were fabricated on a poly(ethylene terephthalate) (PET) substrate using lithography techniques. (3‐Methyl‐3,4‐dihydro‐2H‐thieno[3,4‐b]dioxepin‐3‐yl)methanol (ProDOT‐OH) was self‐synthesized through urethane linkages onto the surface of the patterned photoresist on the PET film, which was then dipped into a solution of another monomer, 3‐thienylethoxybutanesulfonate (TEBS), and initiator and polymerized in situ to form conductive poly(ProDOT‐OH‐co‐TEBS) films covering the surface of the patterned resist. The optimal conductivity of the poly(ProDOT‐OH‐co‐TEBS) films was ca 90 S cm−1 with an optical transparency of ca 70%. A new bottom‐up technique has been developed for the preparation of patterned organic transparent conductive films: self‐synthesis of the monomer using urethane‐forming reactions and subsequent in situ polymerization. The conductivity of the films can be controlled by the polymerization reaction time and the resolution of the pattern. These conductive patterned films might be applicable to the manufacture of industrial touch panels or chemical/biological sensors. Copyright © 2009 Society of Chemical Industry
Polymeric coatings for photostability enhancement of poly(p‐phenylene vinylene) derivative films
Authors: Gonçalves Vanessa C , Carvalho Antonio JF , Balogh Debora T 
Published: December 2009

AbstractPoly(p‐phenylene vinylene) (PPV) derivatives are an important class of conjugated polymers, known for their applications as electroluminescent materials for light‐emitting devices and sensors. These derivatives are highly susceptible to photodegradation by the combined action of oxygen and light. Here, the use of various commercial polymers as protective coatings against the photodegradation of PPV derivatives was explored. Cast films of two similar PPV derivatives, poly[(2‐methoxy‐5‐n‐hexyloxy)‐p‐phenylene vinylene] and poly[2‐methoxy‐5‐(2‐ethylhexyloxy)‐p‐phenylene vinylene], were submitted to photodegradation by exposure to white light under atmospheric conditions in order to verify if the type of side chain (linear or branched) had an effect on the photodegradation. No significant differences in the photodegradation behaviour between the two polymers were noticed. The following commercial polymers were tested as protective coatings for the PPV derivative cast films: 99 and 80% hydrolysed poly(vinyl alcohol) (PVA) and starch. The best results were achieved using coatings of 99% hydrolysed PVA, which increased about 700 times the time necessary for complete degradation of the PPV derivative films. The results show the effectiveness of this coating in minimizing and, possibly, controlling the effects of the photodegradation of PPV derivative films, which can be useful in many applications, e.g. oxygen sensors. Copyright © 2009 Society of Chemical Industry
Versatile modes of peptide recognition by the ClpX N domain mediate alternative adaptor‐binding specificities in different bacterial species
Authors: Chowdhury Tahmeena , Chien Peter , Ebrahim Shamsah , Sauer Robert T. , Baker Tania A. 
Published: December 2009

AbstractClpXP, an AAA+ protease, plays key roles in protein‐quality control and many regulatory processes in bacteria. The N‐terminal domain of the ClpX component of ClpXP is involved in recognition of many protein substrates, either directly or by binding the SspB adaptor protein, which delivers specific classes of substrates for degradation. Despite very limited sequence homology between the E. coli and C. crescentus SspB orthologs, each of these adaptors can deliver substrates to the ClpXP enzyme from the other bacterial species. We show that the ClpX N domain recognizes different sequence determinants in the ClpX‐binding (XB) peptides of C. crescentus SspBα and E. coli SspB. The C. crescentus XB determinants span 10 residues and involve interactions with multiple side chains, whereas the E. coli XB determinants span half as many residues with only a few important side chain contacts. These results demonstrate that the N domain of ClpX functions as a highly versatile platform for peptide recognition, allowing the emergence during evolution of alternative adaptor‐binding specificities. Our results also reveal highly conserved residues in the XB peptides of both E. coli SspB and C. crescentus SspBα that play no detectable role in ClpX‐binding or substrate delivery.
Insight into the structure of the pUL89 C‐terminal domain of the human cytomegalovirus terminase complex
Authors: Couvreux A. , Hantz S. , Marquant R. , Champier G. , Alain S. , Morellet N. , Bouaziz S. 
Published: December 2009

AbstractIn a previous study, we identified 12 conserved domains within pUL89, the small terminase subunit of the human cytomegalovirus. A latter study showed that the fragment pUL89(580–600) plays an important role in the formation of the terminase complex by interacting with the large terminase subunit pUL56. In this study, analysis was performed to solve the structure of pUL89(568–635) in 50% H2O/50% acetonitrile (v/v). We showed that pUL89(568–635) consists of four alpha helices, but we did not identify any tertiary structure. The fragment 580–600 formed an amphipathic alpha helix, which had a hydrophobic side highly conserved among herpesviral homologs of pUL89; this was not observed for its hydrophilic side. The modeling of pUL89(457–612) using the recognition fold method allowed us to position pUL89(580–600) within this domain. The theoretical structure highlighted three important features. First, we identified a metal‐binding pocket containing residues Asp463, Glu534, and Glu588, which are highly conserved among pUL89 homologs. Second, the model predicted a positively charged surface able to interact with the DNA duplex during the nicking event. Third, a hydrophobic patch on the top of the catalytic site suggested that this may constitute part of the pUL89 site recognized by pUL56 potentially involved in DNA binding. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Potential attractants for detecting and removing invading Gambian giant pouched rats (Cricetomys gambianus)
Authors: Witmer Gary W , Snow Nathan P , Burke Patrick W 
Published: December 2009

AbstractBACKGROUND: Native to Africa, Gambian giant pouched rats (Gambian rats; Cricetomys gambianus Waterh.) are a threatening invasive species on a Florida island, Grassy Key. Gambian giant pouched rats shifted from a domestic pet to invading species after suspected release from a pet breeder. Because of the large size of Gambian rats (weighing up to 2.8 kg), they pose a serious threat to native species (particularly nesting species) and agricultural crops, especially if Gambian rats invade mainland Florida. Also, Gambian rats pose a threat from disease, as they were implicated in a monkeypox outbreak in the midwestern United States in 2003. The United States Department of Agriculture's Wildlife Services has initiated eradication and detection efforts in the Florida Keys, but trapping the sparse population of Gambian rats has proven difficult.RESULTS: Fifteen attractants that could be used in traps for capturing or detecting single or paired Gambian rats were tested. It was found that conspecific scents (i.e. feces and urine) from other Gambian rats were the best treatment for attracting single and paired Gambian rats. Single Gambian rats explored more attractant types than paired Gambian rats.CONCLUSIONS: Effective attractants for use with Gambian rats have been identified, and multiple attractant types should be used to capture or detect the sparse population. It is recommended that mainly urine and feces from Gambian rats be used, but peanut butter, anise, ginger and fatty acid scent could also be useful for attracting the currently small population of Gambian rats on Grassy Key. Published in 2009 by John Wiley & Sons, Ltd.
Adipokinetic hormone (Pyrap‐AKH) enhances the effect of a pyrethroid insecticide against the firebug Pyrrhocoris apterus
Authors: Kodrík Dalibor , Bártů Iva , Socha Radomír 
Published: December 2009

AbstractBACKGROUND: Adipokinetic hormones (AKHs) are insect neuropetides controlling stress situations including those elicited by insecticide treatment. The effect of Pyrap‐AKH on the mortality of the firebug Pyrrhocoris apterus (L.) treated with the insecticide permethrin (Ambush 25 EC) was studied.RESULTS: Coinjection of 50 ng permethrin with 80 pmol Pyrap‐AKH induced a significant 2.3‐fold increase in bug mortality compared with the insecticide alone. The results were confirmed by topical coapplication of both agents (400 ng and 80 pmol respectively). Injections of 50 and 100 ng permethrin elicited a significant increase in the AKH level in CNS and the haemolymph. The results indicate an involvement of AKH in stress response to permethrin. The enhanced effect of insecticide by AKH treatments probably results from the stimulatory role in bug metabolism: carbon dioxide production was increased 3.5‐ and 2.5‐fold respectively 1 and 3 h after permethrin treatment, and 4.3‐ and 3.4‐fold after the permethrin plus AKH cotreatment, compared with the control.CONCLUSION: The elevation of metabolism could intensify the permethrin action by its faster penetration into tissues and by stimulation of biochemically active cells, and could be a reason for enhanced action of permethrin after its cotreatment with Pyrap‐AKH. Copyright © 2009 Society of Chemical Industry
Reduction of bias in static closed chamber measurement of δ13C in soil CO2 efflux
Authors: Ohlsson K. E. Anders 
Published: December 2009

AbstractThe 13C/12C ratio of soil CO2 efflux (δe) is an important parameter in studies of ecosystem C dynamics, where the accuracy of estimated C flux rates depends on the measurement uncertainty of δe. The static closed chamber method is frequently used in the determination of δe, where the soil CO2 efflux is accumulated in the headspace of a chamber placed on top of the soil surface. However, it has recently been shown that the estimate of δe obtained by using this method could be significantly biased, which potentially diminish the usefulness of δe for field applications. Here, analytical and numerical models were used to express the bias in δe as mathematical functions of three system parameters: chamber height (H), chamber radius (Rc), and soil air‐filled porosity (θ). These expressions allow optimization of chamber size to yield a bias, which is at a level suitable for each particular application of the method. The numerical model was further used to quantify the effects on the δe bias from (i) various designs for sealing of the chamber to ground, and (ii) inclusion of the commonly used purging step for reduction of the initial headspace CO2 concentration. The present modeling work provided insights into the effects on the δe bias from retardation and partial chamber bypass of the soil CO2 efflux. The results presented here supported the continued use of the static closed chamber method for the determination of δe, with improved control of the bias component of its measurement uncertainty. Copyright © 2009 John Wiley & Sons, Ltd.
Use of bio‐traps with multiple substrates and electron acceptors to optimize remediation
Authors: Fiorenza Stephanie , McClary Amy C. , Lummus Stanford 
Published: December 2009

AbstractBio‐Traps® were used to investigate biodegradation of benzene, methyl tertiary butyl ether (MTBE), and tertiary butyl alcohol (TBA) under different conditions at a fractured rock site to aid the selection of a bioremediation approach. The Bio‐Traps were amended with the 13C‐labeled constituent of interest and sampled sequentially at 15‐, 30‐, 60‐, and 90‐day intervals. The conditions tested were biodegradation during operation of an air sparge system, amendment with nitrate during the air sparge operation, anaerobic biodegradation with the system turned off, and anaerobic biodegradation with nitrate amendment. There was increased biomass with nitrate amendment whether the air sparge system was on or off for all the constituents of interest. The diversity of the microbial community, determined by phospholipid fatty acid analysis, decreased with nitrate amendment as more specialized degraders were selected. The most negative indicators of potential biodegradation performance were observed with the anaerobic control. There was less biomass overall, less incorporation of 13C into biomass, and decreased membrane permeability. As testing with additional amendments continues at the site, it is not yet certain which treatment might be selected for bioremediation, but the Bio‐Trap tests thus far have identified that the in situ, natural attenuation condition is least favorable for biodegradation. © 2009 Wiley Periodicals, Inc.
Evaluation of algal phytoremediation of light extractable petroleum hydrocarbons in subarctic climates
Authors: Jacques Nicole R. , McMartin Dena W. 
Published: December 2009

AbstractThe presence of an organic mat in a hydrocarbon‐impacted creek in Whitehorse, Yukon Territory, Canada was examined for contributions to in situ remediation of petroleum‐contaminated water. This article investigates the role of algae, found in the organic mat, in the remediation of light extractable petroleum hydrocarbons (LEPHs) at the site and in the laboratory. During the study, LEPH concentrations were reduced by 16.8 percent in the presence of algae alone (algal solution) and 30.4 percent in the combined organic mat solution containing microbial consortia. The study results indicate that algal species at the site did not directly phytoremediate hydrocarbons. Rather, they were part of the total biological degradation taking place. © 2009 Wiley Periodicals, Inc.
Application of nonparametric quantile regression to body mass index percentile curves from survey data
Authors: Li Yan , Graubard Barry I. , Korn Edward L. 
Published: December 2009

AbstractIncreasing rates of overweight among children in the U.S. stimulated interest in obtaining national percentile curves of body size to serve as a benchmark in assessing growth development in clinical and population settings. In 2000, the U.S. Centers for Disease Control and Prevention (CDC) developed conditional percentile curves for body mass index (BMI) for ages 2–20 years. The 2000 CDC BMI‐for‐age curves are partially parametric and only partially incorporated the survey sample weights in the curve estimation. As a result, they may not fully reflect the underlying pattern of BMI‐for‐age in the population. This motivated us to develop a nonparametric double‐kernel‐based method and automatic bandwidth selection procedure. We include sample weights in the bandwidth selection, conduct median correction to reduce small‐sample smoothing bias, and rescale the bandwidth to make it scale invariant. Using this procedure we re‐estimate the national percentile BMI‐for‐age curves and the prevalence of high‐BMI children in the U.S. Copyright © 2009 John Wiley & Sons, Ltd.
KMT1E Mediated H3K9 Methylation Is Required for the Maintenance of Embryonic Stem Cells by Repressing Trophectoderm Differentiation
Authors: Lohmann Felix , Loureiro Joseph , Su Hui , Fang Qing , Lei Hong , Lewis Tanya , Yang Yi , Labow Mark , Li En , Chen Taiping , Kadam Shilpa 
Published: December 2009

Abstract
Dynamic regulation of histone methylation by methyltransferases and demethylases plays a central role in regulating the fate of embryonic stem (ES) cells. The histone H3K9 methyltransferase KMT1E, formerly known as ESET or Setdb1, is essential to embryonic development as the ablation of the Setdb1 gene results in peri-implantation lethality and prevents the propagation of ES cells. However, Setdb1-null blastocysts do not display global changes in H3K9 methylation or DNA methylation, arguing against a genome-wide defect. Here we show that conditional deletion of the Setdb1 gene in ES cells results in the upregulation of lineage differentiation markers, especially trophectoderm-specific factors, similar to effects observed upon loss of Oct3/4 expression in ES cells. We demonstrate that KMT1E deficiency in ES cells leads to a decrease in histone H3K9 methylation at and derepression of trophoblast-associated genes such as Cdx2. Furthermore, we find genes that are derepressed upon Setdb1 deletion to overlap with known targets of polycomb mediated repression, suggesting that KMT1E mediated H3K9 methylation acts in concert with polycomb controlled H3K27 methylation. Our studies thus demonstrate an essential role for KMT1E in the control of developmentally regulated gene expression programs in ES cells.