bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Fe2+ ions on morphologies, microstructures and mechanical properties of electrospun nylon‐6 nanofibers
Authors: Kimura Naotaka , Kim Byoung‐Suhk , Kim Ick‐Soo 
Published: April 2013

AbstractIn this study, nylon‐6 nanofiber mats containing Fe2+ ions were fabricated via electrospinning. The resultant electrospun nylon‐6/FeCl2 nanofiber mats were characterized by SEM, TEM, Fourier transform IR spectroscopy, wide angle XRD and DSC. Unique morphological features, such as spider's‐web‐like morphologies, were observed and became evident with increasing additive Fe2+ ions. The metastable γ form was predominant in the as‐spun nylon‐6 nanofibers. The relative intensity of such γ form gradually decreased with increasing additive Fe2+ ions, indicative of transformation of the crystalline structure in the electrospun nylon‐6/FeCl2 nanofibers due to strong molecular interactions between the nylon‐6 backbone and the additive Fe2+ ions. The effects of additive Fe2+ ions on the mechanical properties of both nonwoven nanofiber mats and single nanofibers were investigated. In particular, Young's modulus of nylon‐6/FeCl2 single nanofibers gradually increased from 1.46 to 5.26 GPa with increasing additive Fe2+ ions. © 2013 Society of Chemical Industry
Structure of the RNA‐directed RNA Polymerase from the cystovirus ϕ12
Authors: Ren Zhen , Franklin Matthew C. , Ghose Ranajeet 
Published: April 2013

ABSTRACTWe have determined the structure of P2, the self‐priming RdRp from cystovirus ϕ12 in two crystal forms (A, B) at resolutions of 1.7 Å and 2.1 Å. Form A contains Mg2+ bound at a site that deviates from the canonical noncatalytic position seen in form B. These structures provide insight into the temperature sensitivity of a ts‐mutant. However, the tunnel through which template ssRNA accesses the active site is partially occluded by a flexible loop; this feature, along with suboptimal positioning of other structural elements that prevent the formation of a stable initiation complex, indicate an inactive conformation in crystallo. Proteins 2013; 81:1479–1484. © 2013 Wiley Periodicals, Inc.
Fabrication and characteristics of solution‐processed graphene oxide–silicon heterojunction
Authors: Kalita Golap , Wakita Koichi , Umeno Masayoshi , Tanemura Masaki 
Published: April 2013

AbstractWe demonstrate the fabrication of a solid state heterojunction photovoltaic device with solution‐processed graphene oxide (GO) and n‐Si. Partially reduced GO with a high optical gap (2.8 eV) was spin‐coated on the n‐Si substrate and a heterojunction device was fabricated with the structure of Au/pr‐GO/n‐Si. In the fabricated device, incident light was transmitted through the thin GO film to reach the junction interface, generating photoexciton, and thereby a photovoltaic action was observed. By means of a built‐in electric potential at the GO/n‐Si junction, photoexcited electrons and holes can be separated, transported and collected at the electrodes.magnified imageSolid state heterojunction device fabricated with solution‐processed graphene oxide (high optical gap ∼2.8 eV) and n‐Si.(© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recyclable Polymer‐Supported Nanometal Catalysts in Water
Authors: Ohtaka Atsushi 
Published: April 2013

AbstractTwo types of polymer‐supported nanometal catalysts with high catalytic activity and recyclability in water have been developed. One catalyst was composed of linear polystyrene‐stabilized metal nanoparticles (PS‐MtNPs). A palladium catalyst (PS‐PdONPs) was prepared in water by the thermal decomposition of Pd(OAc)2 in the presence of polystyrene. The degree of immobilization of Pd, but not the size of the Pd nanoparticles, was dependent on the molecular weight and cross‐linking of the polystyrene. The PS‐PdONPs exhibited high catalytic activity for Suzuki, Heck, and Sonogashira coupling reactions in water and they could be recycled without loss of activity. Linear polystyrene was also suitable as a stabilizer for in situ generated PdNPs and PtNPs. The second catalyst was a polyion complex that was composed of poly[4‐chloromethylstyrene‐co‐(4‐vinylbenzyl)tributylammonium chloride] and poly(acrylic acid)‐stabilized PdNPs (PIC‐PdNPs). Aggregation and redispersion of PIC‐PdNPs were easily controlled by adjusting the pH value of the solution.
Copper Solution Chemistry of Cyclic Pseudo‐Octapeptides
Authors: Comba Peter , Dovalil Nina , Haberhauer Gebhard , Kowski Klaus , Mehrkens Nina , Westphal Michael 
Published: April 2013

AbstractThe CuII solution chemistry of synthetic derivatives of naturally occurring pseudo‐octapeptides (patellamides and ascidiacyclamide) is described. The complex stabilities [mono‐ and dicopper(II) complexes] of five different ligands were determined by isothermal microcalorimetry (ITC), and square wave voltammetry (SQW) was used to elucidate the electrochemical properties. In agreement with published spectroscopic data, there is cooperative binding of two CuII ions and the overall stabilities are, in agreement with known stabilities of the natural ligands and expectations based on the donor sets (two N‐based heterocycles and one amide per CuII), only moderate (K ≤ 106). There is a slight dependence of the stabilities on the ligand structure (configuration of the side chains), and that derived from the natural products forms the most stable complexes. Due to the complex equilibria in solution and the instability of the reduced forms, voltammetry shows complex equilibria, which preclude the full assignment of all processes. The positive reduction potentials are in agreement with relatively low complex stabilities. These observations complete earlier studies, concentrating on spectroscopy and structural aspects, and are also discussed in relation to the possible biological function of the cyclic peptides, i.e. metal ion transport, oxygen activation, carboanhydrase, and phosphatase activities.
Dissection of Different Donor Abilities Within Bis(pyrazolyl)­pyridinylmethane Transition Metal Complexes
Authors: Hoffmann Alexander , Herres‐Pawlis Sonja 
Published: April 2013

AbstractUsing the bis(pyrazolyl)pyridinylmethane ligand α,α,α‐bis(1‐pyrazolyl)(2‐pyridinyl)toluene {(ph)C(pz)2(py)} for bioinorganic inspired coordination chemistry studies, we synthesised and structurally characterised three monofacial complexes [{(ph)C(pz)2(py)}CoCl2] (C1), [{(ph)C(pz)2(py)}CuCl2] (C2), [{(ph)C(pz)2(py)}ZnCl2] (C3) and the binuclear halogenido‐bridged complexes [{(ph)C(pz)2(py)}2(μ‐Cl)2Fe2Cl2] (C4) and [{(ph)C(pz)2(py)}2(μ‐Br)2Cu2Br2] (C5). In four of these complexes, severe disorders between pyrazolyl and pyridinyl donor groups are observed such that bis(pyrazolyl) and (pyrazolyl)(pyridinyl) coordination modes are concomitantly found. The donor competition is dissected by DFT calculation of the energy differences between the two coordination modes and NBO analysis of the donor situation. The pyrazolyl units provide with more donor strength although pyridine is considerably more basic.
A Distinct Tetradentate N2O2‐type Ligand: (o‐Carboranyl)bis(2‐hydroxymethyl)pyridine
Authors: Di Salvo Florencia , Teixidor Francesc , Viñas Clara , Giner Planas José 
Published: April 2013

AbstractA new chiral racemic ligand (o‐carboranyl)bis(2‐hydroxymethyl)pyridine oCB(hmpH)2, that is composed of a central o‐carborane unit where two arms radiate out of the cluster carbons each one containing a 2‐pyridylmethylalcohol chelating arms, provides two potentially bidentate {NO} or one tetradentate {N2O2} binding pockets. An unprecedented octahedral CoII complex [CoCl2(anti‐oCB(hmpH)2] was obtained under aerobic conditions and characterized by X‐ray crystallography as well as IR and NMR spectroscopy. anti‐oCB(hmpH)2 acts as a tetradentate N2O2‐ligand affording the complex as a racemic mixture of cis‐α Δ‐[CoCl2(RRanti‐oCB(hmpH)2)] and Λ‐[CoCl2(SSanti‐oCB(hmpH)2)]. The new ligand oCB(hmpH)2 appears to be suitable for producing a variety of new chiral‐at‐metal complexes.
Quantum critical lines in holographic phases with (un)broken symmetry
Authors: Goutéraux B. , Kiritsis E. 
Published: April 2013

AbstractAll possible scaling IR asymptotics in homogeneous, translation invariant holographic phases preserving or breaking a U(1) symmetry in the IR are classified. Scale invariant geometries where the scalar extremizes its effective potential are distinguished from hyperscaling violating geometries where the scalar runs logarithmically. It is shown that the general critical saddle-point solutions are characterized by three critical exponents (θ, z, ζ). Both exact solutions as well as leading behaviors are exhibited. Using them, neutral or charged geometries realizing both fractionalized or cohesive phases are found. The generic global IR picture emerging is that of quantum critical lines, separated by quantum critical points which correspond to the scale invariant solutions with a constant scalar.
Linolenic Acid as the Main Source of Acrolein Formed During Heating of Vegetable Oils
Authors: Endo Yasushi , Hayashi Chieko , Yamanaka Takashi , Takayose Koichi , Yamaoka Miki , Tsuno Takuo , Nakajima Shigeo 
Published: April 2013

AbstractAcrolein, which is an irritating and off‐flavor compound formed during heating of vegetable oils, was estimated by the gas–liquid chromatography (GLC). Several vegetable oils such as high‐oleic sunflower, perilla, rapeseed, rice bran, and soybean oils were heated at 180 °C for 480 min and then the concentration of acrolein in the head space gas was determined by GLC. The formation of acrolein was greatest in perilla oil among the tested oils, while it was much lower in rice bran oil and high‐oleic sunflower oil. There was a good correlation between the level of acrolein and linolenate (18:3n‐3) in the vegetable oils. To investigate the formation of acrolein from linolenate, methyl oleate, methyl linoleate, and methyl linolenate were also heated at 180 °C, and the amounts of acrolein formed from them were determined by GLC. The level of acrolein was the greatest in methyl linolenate. Acrolein was also formed from methyl linoleate, but not from methyl oleate. Acrolein in vegetable oils may be formed from polyunsaturated fatty acids, especially linolenic acid but not from glycerol backbone in triacylglycerols.
A Statistical Appraisal to Hydrogeochemistry of Fluoride Contaminated Ground Water in Nayagarh District, Odisha
Authors: Routroy S. , Harichandan R. , Mohanty J. K. , Panda C.R. 
Published: April 2013

Abstract:
Seasonal variation of ground water in Nayagarh district, Odisha is determined by analysing both pre and post monsoon water samples. The high fluoride content is an endemic problem in the area and special attention was attached to the point. The chemical compositions of the ground water of the area are dominated by CaCl, NaCl and mixed CaMgCl types in pre-monsoon and CaHCO3-mixed CaMgCl type in post-monsoon. This is largely due to chemical weathering of Eastern Ghats Mobile Belt rock types. Increasing alkalinity vis-a-vis F concentration in pre-monsoon is associated with sodium-bicarbonate water types having high pH (&gt;7) and low calcium and magnesium contents. The percentage of total high fluoride containing water samples is nearly double in pre-monsoon than in post-monsoon. During both the seasons, pH values indicate mildly alkaline to weakly acidic nature of the water samples. Fluoride concentration has good correlation with pH in pre-monsoon whereas in post-monsoon it shows good correlation with Fe. Facies analysis indicates that water is becoming predominantly Ca-Na cation and Cl-SO4-HCO3 anion type in pre-monsoon than Ca-Mg type and HCO3- Cl-SO4 type in post-monsoon. The seasonal variations in concentrations of anthropogenic components demonstrate that the groundwater system is very less liable to pollution by human activities.
Antileukemic potential of PEGylated gold nanoparticle conjugated with protein toxin (NKCT1) isolated from Indian cobra (Naja kaouthia) venom
Authors: Bhowmik Tanmoy , Saha Partha Pratim , Dasgupta Anjan , Gomes Antony 
Published: April 2013

Abstract
Limited efficacy of current first-line treatment for leukemia calls attention for further development of efficient strategies. Recently, much attention has been given to nanoparticle-based drug delivery systems loaded with dual drugs to improve current disease therapies by overcoming toxicity. In the present study, we document to explore an approach to conjugate gold nanoparticles (GNPs) with protein toxin (NKCT1), a protein toxin from the Indian cobra (Naja kaouthia) venom, and to establish its antileukemic activity. GNP was prepared by NaBH4 reduction method. UV–vis spectroscopy of GNP showed the absorbance at 530 nm for plasma resonance. Dynamic light scattering (DLS) size of GNPs was 2–8 nm and the GNP-NKCT1 was 68–122 nm. CD spectra of GNP-NKCT1 showed change in percentage of β-turn as compared with NKCT1. GNP-NKCT1 significantly inhibited leukemic cell growth in dose- and time-dependent manner by two- to threefold more than NKCT1. For human leukemic lymphoma cell line and human myelogenous leukemic cell line, the IC50 dose was found to be 1.2 and 0.75 μg/ml, respectively, observed by trypan blue exclusion method and tetrazolium bromide reduction assay. Flow cytometric analysis showed appreciable number of both cell lines in early and late apoptotic stages and arrested cell cycle in the G1 phase by GNP-NKCT1. Resilient power of leukemic cell line after wound healing and migration or invasive power of the cell line was significantly low in GNP-NKCT1-treated plate than the control plate. These analyses reveal that GNP-NKCT1 possesses significant and selective anticancer activity, likely by inducing programmed cell death through mitochondrial and/or lysosomal pathway.
The Politics of Sour Grapes: Sartre, Elster, and Tocqueville on Frustration, Failure, and Self-Deception
Authors: McLendon Michael Locke 
Published: April 2013

AbstractJean-Paul Sartre and Jon Elster have taken great interest in the famous “children's” fable, “The Fox and the Grapes.” Elster believes the fable pinpoints problems in utilitarian doctrine while Sartre contends it demonstrates how consciousness copes with frustrated desire. As impressive as these insights are, neither philosopher can fully explain the cognitive and cultural processes involved in sour grapes. To improve upon their theories, I will argue thatamour-propreis an important psychological motive inspiring sour grapes as well as show that sour grapes is built into the value commitments and institutional structures of democratic life through Tocqueville's analysis of American democracy.
Pits and Place-making: Neolithic Habitation and Deposition Practices in East Yorkshirec. 4000–2500 BC
Authors: Carver Genevieve 
Published: April 2013

This article presents the findings of a study which sought to explore the nature of Neolithic habitation practices in east Yorkshire, primarily using evidence from pits. The morphology of pits and material deposited into them were examined in order to discern the kinds of activities taking place close by, and the possible motivation behind pits being dug. The temporality, spatial organisation, and landscape distribution of pits was considered in conjunction with information from domestic features, artefact spreads, and monumental and funerary features in order to create a coherent image of the ways in which people lived in and exploited the landscape.It is argued that, given the scarcity of direct evidence for residential contexts, the information from pits can tell us about occupation practices. Viewed in conjunction with evidence for changing subsistence practices and an increasingly monumentalised landscape from the Early Neolithic onwards, the deposition of domestic material in pits is interpreted as part of cycles of renewal that created more permanent connections between people and their homes.
ABCA8 stimulates sphingomyelin production in oligodendrocytes
Authors: Kim Woojin Scott , Hsiao Jen-Hsiang T. , Bhatia Surabhi , Glaros Elias N. , Don Anthony S. , Tsuruoka Shuichi , Shannon Weickert Cynthia , Halliday Glenda M. 
Published: April 2013

Members of the ABCA (ATP-binding cassette subfamily A) family are characterized by their ability to transport lipids across cellular membranes and regulate lipid homoeostasis in the brain and peripheral tissues. ABCA8 is a little-known member of this subfamily that was originally cloned from human brain libraries and has no known function. In an effort to elucidate the role of ABCA8 in the brain we first undertook a comprehensive analysis of its expression in the human brain. ABCA8 was differentially expressed in multiple regions of adult human brains with significantly higher expression in oligodendrocyte-enriched white matter regions compared with grey matter cortical regions. We then assessed the impact of ABCA8 on sphingomyelin production in oligodendrocyte and showed that ABCA8 was able to significantly stimulate both sphingomyelin synthase 1 expression and sphingomyelin production. Furthermore, ABCA8 expression in the prefrontal cortex across the human life span correlated strongly with age-associated myelination, and the myelinating gene p25α was significantly up-regulated with ABCA8. The present study represents the first extensive expression and functional study of ABCA8 in the human brain and the results strongly suggest that ABCA8 regulates lipid metabolism in oligodendrocytes and potentially plays a role in myelin formation and maintenance.
Structural and functional interactions of the prostate cancer suppressor protein NKX3.1 with topoisomerase I
Authors: Song Liang-Nian , Bowen Cai , Gelmann Edward P. 
Published: April 2013

NKX3.1 (NK3 homeobox 1) is a prostate tumour suppressor protein with a number of activities that are critical for its role in tumour suppression. NKX3.1 mediates the cellular response to DNA damage by interacting with ATM (ataxia telangiectasia mutated) and by activation of topoisomerase I. In the present study we characterized the interaction between NKX3.1 and topoisomerase I. The NKX3.1 homeodomain binds to a region of topoisomerase I spanning the junction between the core and linker domains. Loss of the topoisomerase I N-terminal domain, a region for frequent protein interactions, did not affect binding to NKX3.1 as was shown by the activation of Topo70 (N-terminal truncated topoisomerase I) in vitro. In contrast, NKX3.1 interacts with the enzyme reconstituted from peptide fragments of the core and linker active site domains, but inhibits the DNA-resolving activity of the reconstituted enzyme in vitro. The effect of NKX3.1 on both Topo70 and the reconstituted enzyme was seen in the presence and absence of camptothecin. Neither NKX3.1 nor CPT (camptothecin) had an effect on the interaction of the other with topoisomerase I. Therefore the interactions of NKX3.1 and CPT with the linker domain of topoisomerase I are mutually exclusive. However, in cells the effect of NKX3.1 on topoisomerase binding to DNA sensitized the cells to cellular toxicity and the induction of apoptosis by low doses of CPT. Lastly, topoisomerase I is important for the effect of NKX3.1 on cell survival after DNA damage as topoisomerase knockdown blocked the effect of NKX3.1 on clonogenicity after DNA damage. Therefore NKX3.1 and topoisomerase I interact in vitro and in cells to affect the CPT sensitivity and DNA-repair functions of NKX3.1.
Optical control demonstrates switch-like PIP3 dynamics underlying the initiation of immune cell migration
Authors: Karunarathne W. K. Ajith , Giri Lopamudra , Patel Anilkumar K. , Venkatesh Kareenhalli V. , Gautam N. 
Published: April 2013

Significance
Here we used a visual blue opsin to induce asymmetric signaling in a cell. The opsin recruited endogenous G proteins and allowed immune cell migration to be optically steered with directional precision. Using this approach, cellular and molecular response dynamics were quantitated to facilitate computational modeling of migration. We identified an ultrasensitive switch-like signaling response that explains how immune cells filter background fluctuations in signals and respond decisively to persistent stimuli. This approach can be widely applied to understand G-protein–coupled receptor-stimulated signaling network control of other cell behaviors and potentially to control cell movements in whole animals.
Teaching and Assessing Residents’ Skills in Managing Heroin Addiction with Objective Structured Clinical Examinations (OSCEs)
Authors: Parish Sharon J. , Stein Melissa R. , Hahn Steven R. , Goldberg Uri , Arnsten Julia H. 
Published: April 2013

Background Heroin-abusing patients present a significant challenge. Objective Structured Clinical Examinations (OSCEs) allow evaluation of residents’ clinical skills. The objective of this study was to examine residents’ OSCE performance assessing and managing heroin abuse. Methods Evaluation and comparison of heroin-specific communication, assessment, and management skills in a 5-station postgraduate year 3 (PGY3) substance abuse OSCE. Faculty used a 4-point Likert scale to assess residents’ skills; standardized patients provided written comments. Results Two hundred sixty-five internal and family medicine residents in an urban university hospital participated over 5 years. In the heroin station, residents’ skills were better ( P < .001 for both comparisons) in communication (mean overall score: 316 ± 0.51) than in either assessment (mean overall score: 2.66 ± 0.60) or management (mean overall score: 2.50 ± 0.73). The mean score for assessing specific high-risk behaviors was lower than the mean overall assessment score (222 ± 1.01 vs. 2.74 ± .59; P < .0001), and the mean score for recommending appropriate harm reduction management strategies was lower than the mean overall management score (2.39 ± .89 vs. 2.54 ± .74; P < .005). Standardized patients’ comments reflected similar weaknessess in residents’ skills. Conclusions Assessment and management of heroin abuse were more challenging for residents than general communication. Additional training is required for residents to assess and counsel patients about high-risk behaviors.
Saving Costs through the Decontamination of the Packaging of Unused Medical Supplies Using Hydrogen Peroxide Vapor
Authors: Otter Jonathan A. , Nowakowski Elaine , Salkeld James A. G. , Duclos Mike , Passaretti Catherine L. , Yezli Saber , Ross Tracy , Carroll Karen C. , Perl Trish M. 
Published: April 2013

Objective.Individually packaged sterile supply items may become contaminated and act as vectors for nosocomial transmission of multidrug-resistant organisms (MDROs). Thus, many hospitals have a policy to dispose of these unused, packaged supply items at patient discharge from the hospital, which has considerable cost implications. We evaluated the frequency of contamination of these items, the efficacy of hydrogen peroxide vapor (HPV) in disinfecting them, and costs associated with discarded supplies.Design.Before-after study.Methods.A pilot study was performed in the rooms of 20 patients known to be colonized or infected with vancomycin-resistant enterococci (VRE), and a follow-up study was performed in an additional 20 rooms of patients under precautions for various MDROs in 6 high-risk units. Five pairs of supply items were selected. One item of each pair was sampled without exposure to HPV, and the other was sampled after HPV exposure. The cost of discarded supplies was calculated by examining stock lists of supplies stored on the study units.Results.Seven (7%) of 100 items were contaminated with VRE in the pilot study, and 9 (9%) of 100 items were contaminated with MDROs in the follow-up study. None of the items were contaminated after exposure to HPV (P < .02 in both the pilot and the follow-up study). The annual cost of supplies discarded at patient hospital discharge was $387,055. This figure does not include the cost of waste disposal and is therefore likely to be an underestimation of the financial burden.Conclusions.HPV effectively disinfected the packaging of supply items, which could generate considerable financial and environmental benefits.