bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, Photophysics and Nonlinear Optical Properties of Stilbenoid Pyrimidine‐Based Dyes Bearing Methylenepyran Donor Groups
Authors: Achelle Sylvain , Malval Jean‐Pierre , Aloïse Stéphane , Barsella Alberto , Spangenberg Arnaud , Mager Loic , Akdas‐Kilig Huriye , Fillaut Jean‐Luc , Caro Bertrand , Robin‐le Guen Françoise
Published: July 2013

The nonlinear properties and the photophysical behavior of two π‐conjugated chromophores that incorporate an electron‐deficient pyrimidine core (A) and γ‐methylenepyrans as terminal donor (D) groups have been thoroughly investigated. Both dipolar and quadrupolar branching strategies are explored and rationalized on the basis of the Frenkel exciton model. Even though a cooperative effect is clearly observed if the dimensionality is increased, the nonlinear optical (NLO) response of this series is moderate if one considers the nature of the D/A couple and the size of the chromophores (as measured by the number of π electrons). This effect was attributed to a disruption in the electronic conjugation within the dyes’ scaffold for which the geometry deviates from planarity owing to a noticeable twisting of the pyranylidene end‐groups. This latter structural parameter also has a strong influence on the excited‐state dynamics, which leads to a very efficient fluorescence quenching.
The Reaction and Materials Chemistry of [Sn6(O)4(OSiMe3)4]: Chemical Vapour Deposition of Tin Oxide
Authors: Barbul Ioana , Johnson Andrew L. , Kociok‐Köhn Gabriele , Molloy Kieran C. , Silvestru Christian , Sudlow Anna L.
Published: July 2013

[Sn6(O)4(OSiMe3)4] and [{Sn(OSiMe3)2}2] have been used to deposit SnO thin films by chemical vapour deposition. Films derived from [Sn6(O)4(OSiMe3)4] comprise uniform cubes and are highly oriented, whereas those deposited from [{Sn(OSiMe3)2}2] are made up of a continuous non‐oriented layer with oriented cubes on the surface. The structure of a co‐crystal, 2 Sn6(O)4(OSiMe3)4⋅[Sn(OSiMe3)2]2⋅4 THF, shows that [{Sn(OSiMe3)2}2], a liquid at room temperature, adopts a μ‐OSiMe3‐bridged dimeric structure. [Sn6(O)4(OSiMe3)4] reacts with O2 in a controlled manner to afford the novel oxo‐cluster [Sn4(O)(OSiMe3)8], the structure of which is reported. In addition, a crystal of {[Sn4(O)(OSiMe3)5]+2[Sn(O)(OSiMe3)4Cl]+2}[Cl]−4 has been fortuitously isolated from the presence of SnCl2 in the starting material for the preparation of [Sn6(O)4(OSiMe3)4], and has been shown to incorporate two novel cationic oxo–tin clusters.
CaO‐Based CO2 Sorbents: From Fundamentals to the Development of New, Highly Effective Materials
Authors: Kierzkowska Agnieszka M. , Pacciani Roberta , Müller Christoph R.
Published: July 2013

The enormous anthropogenic emission of the greenhouse gas CO2 is most likely the main reason for climate change. Considering the continuing and indeed growing utilisation of fossil fuels for electricity generation and transportation purposes, development and implementation of processes that avoid the associated emissions of CO2 are urgently needed. CO2 capture and storage, commonly termed CCS, would be a possible mid‐term solution to reduce the emissions of CO2 into the atmosphere. However, the costs associated with the currently available CO2 capture technology, that is, amine scrubbing, are prohibitively high, thus making the development of new CO2 sorbents a highly important research challenge. Indeed, CaO, readily obtained through the calcination of naturally occurring limestone, has been proposed as an alternative CO2 sorbent that could substantially reduce the costs of CO2 capture. However, one of the major drawbacks of using CaO derived from natural sources is its rapidly decreasing CO2 uptake capacity with repeated carbonation–calcination reactions. Here, we review the current understanding of fundamental aspects of the cyclic carbonation–calcination reactions of CaO such as its reversibility and kinetics. Subsequently, recent attempts to develop synthetic, CaO‐based sorbents that possess high and cyclically stable CO2 uptakes are presented.
Efficient threshold public key encryption with full security based on dual pairing vector spaces
Authors: Gan Yuanju , Wang Lihua , Wang Licheng , Pan Ping , Yang Yixian
Published: July 2013

Most robust and noninteractive threshold public key encryption (PKE) schemes have only been proven secure against chosen‐ciphertext attacks under the static corruption model; yet, the dynamic corruption model is more reasonable. In this paper, on the basis of bilinear groups of prime order and dual pairing vector spaces, we propose a threshold PKE scheme that is noninteractive, robust and, secure against adaptive chosen‐ciphertext attacks under the dynamic corruption model without random oracles. Moreover, our scheme is shown to be more efficient than currently existing fully secure threshold PKE schemes. Copyright © 2013 John Wiley & Sons, Ltd.
Neuropeptide orphanin FQ inhibits dendritic morphogenesis through activation of RhoA
Authors: Alder Janet , Kallman Seth , Palmieri Alicia , Khadim Farah , Ayer Jennifer J. , Kumar Sujata , Tsung Katherine , Grinberg Ilya , Thakker‐Varia Smita
Published: July 2013

Brain‐derived neurotrophic factor (BDNF) plays a facilitatory role in neuronal development and promotion of differentiation. Mechanisms that oppose BDNF's stimulatory effects create balance and regulate dendritic growth. However, these mechanisms have not been studied. We have focused our studies on the BDNF‐induced neuropeptide OrphaninFQ/ Nociceptin (OFQ); while BDNF is known to enhance synaptic activity, OFQ has opposite effects on activity, learning, and memory. We have now examined whether OFQ provides a balance to the stimulatory effects of BDNF on neuronal differentiation in the hippocampus. Golgi staining in OFQ knockout (KO) mice revealed an increase in primary dendrite length as well as spine density, suggesting that endogenous OFQ inhibits dendritic morphology. We have also used cultured hippocampal neurons to demonstrate that exogenous OFQ has an inhibitory effect on dendritic growth and that the neuropeptide alters the response to BDNF when pre‐administered. To determine if BDNF and OFQ act in a feedback loop, we inhibited the actions of the BDNF and OFQ receptors, TrkB and NOP using ANA‐12 and NOP KO mice respectively but our data suggest that the two factors do not act in a negative feedback loop. We found that the inhibition of dendritic morphology induced by OFQ is via enhanced RhoA activity. Finally, we have evidence that RhoA activation is required for the inhibitory effects of OFQ on dendritic morphology. Our results reveal basic mechanisms by which neurons not only regulate the formation of proper dendritic growth during development but also control plasticity in the mature nervous system. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 769–784, 2013
Possible roles of robo1+ ensheathing cells in guiding dorsal‐zone olfactory sensory neurons in mouse
Authors: Aoki Mari , Takeuchi Haruki , Nakashima Ai , Nishizumi Hirofumi , Sakano Hitoshi
Published: July 2013

In the mouse olfactory system, the anatomical locations of olfactory sensory neurons (OSNs) correlate with their axonal projection sites along the dorsoventral axis of the olfactory bulb (OB). We have previously reported that Neuropilin‐2 expressed by ventral‐zone OSNs contributes to the segregation of dorsal and ventral OSN axons, and that Slit is acting as a negative land mark to restrict the projection of Robo2+, early‐arriving OSN axons to the embryonic OB. Here, we report that another guidance receptor, Robo1, also plays an important role in guiding OSN axons. Knockout mice for Robo1 demonstrated defects in targeting of OSN axons to the OB. Although Robo1 is colocalized with dorsal‐zone OSN axons, it is not produced by OSNs, but instead by olfactory ensheathing cells. These findings indicate a novel strategy of axon guidance in the mouse olfactory system during development. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73:828–840, 2013
Homothorax plays autonomous and nonautonomous roles in proximodistal axis formation and migration of the Drosophila renal tubules
Authors: Zohar‐Stoopel Adi , Gonen Nitzan , Mahroum Mohammed , Ben‐Zvi Doreen S. , Toledano Hila , Salzberg Adi
Published: July 2013

The Drosophila Malpighian tubules (MpTs) serve as a functional equivalent of the mammalian renal tubules. The MpTs are composed of two pairs of epithelial tubes that bud from the midgut–hindgut boundary during embryogenesis. The MpT primordia grow, elongate and migrate through the body cavity to assume their final position and shape. The stereotypic pattern of MpT migration is regulated by multiple intrinsic and extrinsic signals, many of which are still obscure. In this work, we implicate the TALE‐class homeoprotein Homothorax (Hth) in MpT patterning. We show that in the absence of Hth the tubules fail to rearrange and migrate. Hth plays both autonomous and nonautonomous roles in this developmental process. Within the tubules Hth is required for convergent extension and for defining distal versus proximal cell identities. The difference between distal and proximal cell identities seems to be required for proper formation of the leading loop. Outside the tubules, wide‐range mesodermal expression of Hth is required for directing anterior migration. The nonautonomous effects of Hth on MpT migration can be partially attributed to its effects on homeotic determination along the anterior posterior axis of the embryo and to its effects on stellate cell (SC) incorporation into the MpT. Developmental Dynamics 243:132–144, 2014. © 2013 Wiley Periodicals, Inc.
Changes in the ecosystem service values of typical river basins in arid regions of Northwest China
Authors: Huang X. , Ma J. X.
Published: July 2013

This study compared the 1994 and 2005 ecosystem service values of the Tarim, Manas, Shiyang and Heihe River Basins, which are four typical examples of river basins in the arid region of Northwest China. The ecosystem areas and service values were obtained from their consumer price indices, and constant prices were calculated on the basis of data from the Land Use Classification Map of 1994, TM images, CBERS images of 2005 and research results from ‘the equivalent factor table of China's ecosystem service value’. The results indicated that between 1994 and 2005 in these four river basins, the land areas supporting the environment and society (i.e. forest, grassland and wetland ecosystem) generally declined, whereas areas of farmland significantly increased. The changes in these areas in smaller basins were larger and occurred more rapidly. The ecosystem service value of the Tarim River Basin was the largest and local residents would rather pay more money for its ecosystem services, which means that the ecosystem service value there had a higher scarcity. The increase in the ecosystem service value of the Heihe River Basin was the largest. The ecosystem service value of the Heihe River Basin had more important and direct influences on the population's productivity and lives than did the Tarim River Basin. In addition, the farmland area in the Tarim River Basin increased more than the other river basins; however, the people's willingness to pay for farmland ecosystem services in this basin was the lowest. Willingness to pay was not linked to resource richness, and the concepts of economic development, water utilization and soil protection need to be strengthened. Copyright © 2013 John Wiley & Sons, Ltd.
IFN‐γ production by CD27+NK cells exacerbates Listeria monocytogenes infection in mice by inhibiting granulocyte mobilization
Authors: Viegas Nuno , Andzinski Lisa , Wu Ching‐Fang , Komoll Ronja‐Melinda , Gekara Nelson , Dittmar Kurt E. , Weiss Siegfried , Jablonska Jadwiga
Published: July 2013

Natural killer (NK) cells are key components of the immune system involved in several immune reactions, including the clearance of intracellular pathogens. When activated, NK cells rapidly secrete particular cytokines that activate innate immunity and facilitate development of adaptive responses. Conflicting reports on the role of NK cells during infection by Listeria monocytogenes can be found in the literature. Here, we demonstrate that during lethal infection by L. monocytogenes, activation of NK cells via the costimulatory molecule CD27 leads to excessive IFN‐γ production. This impairs innate anti‐bacterial host defenses by inducing downregulation of CXCR2 on granulocytes and consequently inhibiting their recruitment to the sites of infection. The use of antibodies to block CD27 signaling or to deplete IFN‐γ was sufficient to rescue mice from lethal challenge by L. monocytogenes. Our findings contribute to a better understanding of the importance of CD27 signaling in activation of NK cells and should provide new ways of interfering with infections.
Cobalt‐Catalyzed Oxidation of Methane to Methyl Trifluoroacetate by Dioxygen
Authors: Strassner Thomas , Ahrens Sebastian , Muehlhofer Michael , Munz Dominik , Zeller Alexander
Published: July 2013

The cobalt‐catalyzed oxidation of methane to methyl trifluoroacetate by molecular oxygen in trifluoroacetic acid has been studied in detail. Yields of up to 50 % based on methane were obtained. The catalytic activities were highly dependent on the anions of the cobalt salts (CoII, CoIII) under investigation. Deactivation by precipitation of the cobalt catalyst could be prevented by the addition of trifluoroacetic anhydride.
Di‐ and Tetranuclear Complexes of Bis‐Tetradentate Pyrimidine‐Based Ligands with All‐Methylene‐ Versus Mixed Methylene/Ethylene‐Linked Arms
Authors: Gobeze Worku A. , Milway Victoria A. , Chilton Nicholas F. , Moubaraki Boujemaa , Murray Keith S. , Brooker Sally
Published: July 2013

Eleven dinuclear and six tetranuclear complexes of two bis‐tetradentate ligands, 4,6‐bis[N,N‐bis(2″‐pyridylmethyl)aminomethyl]‐2‐phenylpyrimidine (LMe) and 4,6‐[(2′‐pyridylmethyl)(2′‐pyridylethyl)aminomethyl]‐2‐phenylpyrimidine (LMix), have been prepared through reactions of ligand and metal salt in a ratio of 1:2 in MeCN or MeOH: FeII2LMe(H2O)4(MeCN)2(BF4)4 (1), FeII2LMix(H2O)4(BF4)4 (2), [CoII2LMe(H2O)(MeCN)](BF4)4·3/2H2O (3), [CoII2LMix(H2O)(MeCN)3](BF4)4·2H2O (4), [NiII2LMe(H2O)4](BF4)4·H2O (5), [NiII2LMix(H2O)3(MeCN)](BF4)4 (6), CuII2LMe(H2O)(MeCN)(BF4)4 (7), [CuII2Mix(MeCN)2(BF4)4] (8), [ZnII2LMe(H2O)(MeCN)3(BF4)4] (9), [ZnII2LMix(MeCN)3(H2O)(BF4)4] (10), [ZnII2LMe(H2O)2L(MeCN)2](ClO4)4 (11), FeII2FeIII2(LMe)2F4(BF4)6·1/2H2O (12), FeII4(LMix)2F4(BF4)4·5H2O (13), CoII2CoIII2(LMe)2F4(BF4)6 (14), [CoII4(LMix)2F4](BF4)4·3H2O (15), [NiII4(LMe)2F4](BF4)4 (16) and NiII4(LMix)2F4(BF4)4·8H2O (17). Dinuclear complexes were obtained from the reactions conducted in MeCN, whereas tetranuclear complexes resulted from reactions performed in MeOH. Five dimetallic (3′–6′ and 9′) and one tetrametallic complex (15′) were structurally characterized: the ligands are bis‐tetradentate and the metal centres are bridged through the pyrimidine ring. In the tetrametallic 15′, two such dimetallic fragments are bridged by two pairs of fluoride anions. Variable‐temperature magnetic susceptibility measurements and Heisenberg fitting of dinuclear 1–8 and tetranuclear 13–15 in all cases revealed weak intramolecular anti‐ferromagnetic exchange coupling between the high‐spin metal centres. A rigorous spin–orbit and exchange analysis was also performed on the dicobalt(II) complex 4. The dicopper(II) complexes 7 and 8 underwent a two‐electron quasi‐reversible reduction (CuII2 → CuI2), in both cases at a more negative potential (7: Em = –0.18 V; 8: Em = –0.19 V vs. 0.01 M AgNO3/Ag) than the analogous LEt (all‐ethylene‐armed ligand) complex (Em = +0.11 V vs. 0.01 M AgNO3/Ag), consistent with LMe and LMix being better able to stabilize copper(II) than LEt.
Controlled Synthesis of Polyoxopalladates, and Their Gas‐Phase Fragmentation Study by Electrospray Ionization Tandem Mass Spectrometry
Authors: Lin Zhengguo , Wang Bo , Cao Jie , Chen Baokuan , Xu Chong , Huang Xianqiang , Fan Yanxuan , Hu Changwen
Published: July 2013

Invited for the cover of this issue is the group of Changwen Hu at the Beijing Institute of Technology, China. The cover image shows the most recent developments in the synthesis and study of the gas‐phase fragmentation of new polyoxopalladates.
Using Cognitive Behavior Therapy in Clinical Work With African American Children and Adolescents: A Review of the Literature
Authors: Wilson Courtney J. , Cottone R. Rocco
Published: July 2013

A comprehensive review of the literature on clinical work with African American youth with cognitive behavior therapy (CBT) is presented. The strengths and limitations of CBT in relation to this population are outlined. Although CBT shows promise in helping, research on the efficacy and effectiveness of CBT in this group is lacking.

Se presenta una reseña exhaustiva de la literatura sobre trabajo clínico con jóvenes Afroamericanos usando terapia cognitiva conductual (TCC). Se perfilan los puntos fuertes y las limitaciones de la TCC en relación a esta población. A pesar de que la TCC muestra signos prometedores para servir de ayuda, no hay suficiente investigación sobre la eficacia y efectividad de la TCC en este grupo.
Prevalent Vertebral Fractures on Chest CT: Higher Risk for Future Hip Fracture
Authors: Buckens Constantinus F , de Jong Pim A , Mali Willem P , Verhaar Harald J , van der Graaf Yolanda , Verkooijen Helena M
Published: July 2013

Subclinical or undiagnosed vertebral fractures on routine chest computed tomography (CT) may be useful for detecting patients at increased risk of future hip fractures who might benefit from preventive interventions. We investigated whether prevalent vertebral fractures on routine chest CT are associated with future hip fractures. From a source population of 5679 patients ≥40 years old undergoing chest CT in one of three Dutch hospitals between 2002 and 2005, patients hospitalized for hip fractures (n = 149) during a median follow-up of 4.4 years were identified. Following a case-cohort design, a random sample of 576 patients was drawn from the source population and added to the cases. In this group, the presence and severity of vertebral fractures was determined using semiquantitative vertebral fracture assessment and multivariate case-cohort appropriate Cox modeling. We found that cases were older (69 versus 63 years) and more often female (48% versus 38%) than the source population. Compared with those with no fracture, patients with any vertebral fracture had triple the risk of future hip fracture (age- and gender-adjusted hazard ratio [HR] = 3.1, 95% confidence interval [CI] 2.1–4.7). This HR rose to 3.8 (CI 2.6–5.6) if mild fractures were discounted. Future fracture risk increased significantly with increasing severity of vertebral fracture status: from mild (HR = 2.4, CI 1.5–3.7) and moderate (HR = 4.8, CI 2.5–9.2) to severe (HR = 6.7, CI 2.9–15.5). The same was true for having higher cumulative fracture grades: 1 to 3 (HR = 2.7, CI 1.8–4.1), 4 to 6 (HR = 4.8, CI 2.2–10.5), or ≥7 (HR = 11.2, CI 3.7–34.6). In conclusion, prevalent vertebral fractures on routine clinical chest CT are associated with future hip fracture risk. © 2014 American Society for Bone and Mineral Research.
Feasibility of high pressure freezing with freeze substitution after long‐term storage in chemical fixatives
Authors: Venter Chantelle , Frederick van der Merwe Christiaan , Magdalena Oberholzer Hester , Bester Megan Jean , Taute Helena
Published: July 2013

Fixation of biological samples is an important process especially related to histological and ultrastructural studies. Chemical fixation was the primary method of fixing tissue for transmission electron microscopy for many years, as it provides adequate preservation of the morphology of cells and organelles. High pressure freezing (HPF) and freeze substitution (FS) is a newer alternative method that rapidly freezes non‐cryoprotected samples that are then slowly heated in the FS medium, allowing penetration of the tissue to insure adequate fixation. This study addresses several issues related to tissue preservation for electron microscopy. Using mice liver tissue as model the difference between samples fixed chemically or with HPF immediately after excision, or stored before chemical or HPF fixation were tested with specific focus on the nuclear membrane. Findings are that immediate HPF is the method of choice compared to chemical fixation. Of the chemical fixatives, immediate fixation with 2.5% glutaraldehyde (GA)/formaldehyde (FA) is the best in preserving membrane morphology, 2.5% GA can be used as alternative for stored and then chemically processed samples, with 10% formalin being suitable as a storage medium only if followed by HPF fixation. Overall, storage leads to lower ultrastructural preservation, but HPF with FS can minimize these artifacts relative to other processing protocols. Microsc. Res. Tech. 76:942–946, 2013. © 2013 Wiley Periodicals, Inc.
Immunolocalization of estrogen and progesterone receptors in ewe mammary glands
Authors: Colitti M. , Parillo F.
Published: July 2013

Immunopresence of estrogen receptor α (ERα), β (ERβ) and progesterone receptor (PR) were examined in the ewe mammary gland from prepubertal stage to involution. Immunolocalization of ERα revealed a strong positive staining in nuclei of cells composing terminal ductular units (TDUs) in prepubertal ewes. A mild immunoreactivity was identified in early lactating gland. During late lactation immunoreactive product to ERα was observed in the cytoplasm of glandular epithelial cells in all alveoli. In mammary glands at involution ERα positivity was clearly nuclear, with weak to moderate cytoplasmic staining. Cytoplasmic strong immunostaining for ERβ was detected in cells of TDUs, whereas some stromal cells exhibited nuclear staining. A nuclear ERβ immunostaining was observed at early lactation, instead during late lactation, the positivity for ERβ showed only a moderate cytoplasmic distribution. At involution, ERβ positivity was very moderate and detected just in the cytoplasm of shrunken alveoli. Scattered nuclear staining of PR was observed just in mammary glands at early lactation. These results showed that in the mammary glands of sheep both estrogen receptor isoforms were displayed during lactation cycle and that PR appeared just at early lactation, reflecting their regulatory role in alveolar cells. Microsc. Res. Tech. 76:955–962, 2013. © 2013 Wiley Periodicals, Inc.
Effects of present‐day deglaciation in Iceland on mantle melt production rates
Authors: Schmidt P. , Lund B. , Hieronymus C. , Maclennan J. , Árnadóttir T. , Pagli C.
Published: July 2013

Ongoing deglaciation in Iceland not only causes uplift at the surface but also increases magma production at depth due to decompression of the mantle. Here we study glacially induced decompression melting using 3‐D models of glacial isostatic adjustment in Iceland since 1890. We find that the mean glacially induced pressure rate of change in the mantle increases melt production rates by 100–135%, or an additional 0.21–0.23 km3 of magma per year beneath Iceland. Approximately 50% of this melt is produced underneath central Iceland. The greatest volumetric increase is found directly beneath Iceland's largest ice cap, Vatnajökull, colocated with the most productive volcanoes. Our models of the effect of deglaciation on mantle melting predict a significantly larger volumetric response than previous models which only considered the effect of deglaciation of Vatnajökull, and only mantle melting directly below Vatnajökull. Although the ongoing deglaciation significantly increases the melt production rate, the increase in melt supply rate at the base of the lithosphere is delayed and depends on the melt ascent velocity through the mantle. Assuming that 25% of the melt reaches the surface, the upper limit on our deglaciation‐induced melt estimates for central Iceland would be equivalent to an eruption the size of the 2010 Eyjafjallajökull summit eruption every seventh year.
Instrumental temperature series in eastern and central China back to the nineteenth century
Authors: Cao Lijuan , Zhao Ping , Yan Zhongwei , Jones Phil , Zhu Yani , Yu Yu , Tang Guoli
Published: July 2013

In this study, we bring together different source data sets and use quality control, interpolation, and homogeneity methods to construct a set of homogenized monthly mean surface air temperature (SAT) series for 18 stations in eastern and central China from the late nineteenth century. Missing values are statistically interpolated, and cross validation is used to assess the accuracy of the interpolation approaches. Results show that the errors of interpolation are small, and the interpolated values are statistically acceptable. Multiple homogeneity methods and all available metadata are used to assess the consistency of the time series and then to develop adjustments when necessary. Thirty‐three homogeneity breakpoints are detected in the 18 stations, and the time series is adjusted to the latest segment of the data series. The adjusted annual mean SAT generally shows a range of trends of 1.0° to 4.2°C/100 years in northeastern and southeastern China and a range of trends of −0.3° to 1.0°C/100 years in central China near 30°N. Compared to the adjusted time series, the unadjusted time series underestimates the warming trend during the past 100 years. The regional and annual mean SAT over eastern and central China agrees well with estimates from a much denser station network over this region of China since 1951 and shows a warming trend of 1.52°C/100 years during 1909–2010.
Modeling of peak voltage and current of nanowire resonant tunneling devices: case study on InAs/InP double‐barrier heterostructures
Authors: Ragi R. , da Nobrega Rafael V.T. , Romero Murilo A.
Published: July 2013

In this paper, we develop an analytical model for the prediction of the peak voltage and the current in the current–voltage characteristics of nanowire resonant tunneling heterostructures. The model is applied in the case study of double‐barrier InAs/InP devices, and the results are obtained from numerical carrier transport calculations, in terms of structural parameters such as the nanowire radius as well as the width of the barriers and quantum well. Copyright © 2013 John Wiley & Sons, Ltd.
Use of dithiothreitol to improve the diagnosis of prosthetic joint infections
Authors: Drago Lorenzo , Signori Valentina , De Vecchi Elena , Vassena Christian , Palazzi Elisa , Cappelletti Laura , Romanò Delia , Romanò Carlo Luca
Published: July 2013

Diagnosis of prosthetic joint infections (PJIs) remains a challenge for microbiologists, despite new techniques for bacteria isolation have been developed in recent years. A widely recognized standard method has not yet been indicated mainly because of limitations due difficult procedures and need of dedicated instrumentation. We evaluated the ability of a sulfhydryl compound routinely used in microbiology laboratories, dithiothreitol (DTT), to dislodge bacteria from biofilm, keeping them alive and cultivable for identification and antibiotic susceptibility testing. We compared DTT treatment against sonication of prosthesis and culture of periprosthetic tissues, in order to establish if it could be introduced in routine microbiological diagnosis of PJIs. The study was conducted on 76 patients, 34 with aseptic loosening of their prosthesis and 42 who were diagnosed for PJI. DTT treatment gave results similar to sonication in terms of bacterial yielding. Sonication provided higher sensitivity (71.4%) and specificity (94.1%) respect to periprosthetic tissue culture, while DTT showed the same specificity of sonication but a better sensitivity (85.7%), especially when the causative microorganism was Staphylococcus epidermidis. In conclusion, we demonstrated that DTT could be used for PJIs diagnosis, thanks to its ease of use and its high sensitivity and specificity. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1694–1699, 2013
Ultra‐high performance size‐exclusion chromatography of synthetic polymers
Authors: Janco Miroslav , Alexander James N. , Bouvier Edouard S. P. , Morrison Damian
Published: July 2013

Ultra‐high performance size‐exclusion chromatography (UHP SEC) is a newly developed disruptive technology that allows the high‐resolution separation of synthetic polymers in as little as 2 min. The capability of UHP SEC for the characterization of synthetic polymers in organic solvents has been demonstrated. Using the Waters ACQUITY UPLC®1 H‐Class system and ethylene‐bridged hybrid size‐exclusion chromatography (SEC) columns packed with 1.7 to 2.5‐μm particles with pore sizes ranging from 45 to 900 Å, size‐based separations of polystyrene and poly(methyl methacrylate) standards in tetrahydrofuran and poly(ethylene oxide) standards in 20 mM ammonium acetate in methanol are achieved within 2–4 min. The speed of analysis is about ten times faster than conventional SEC separations, and greater resolution is achieved. Average molecular weights of selected commercial polymers have been determined using ultra‐high performance and conventional SEC. Average M data of analyzed samples are in good agreement using the two approaches. An inherent limitation of SEC in UHP mode is the characterization of very high M polymers (above ca. 2 million Da) due to the deformation and/or mechanical shearing of large molecules at high flow rates.
Frontal sinus septations predict the presence of supraorbital ethmoid cells
Authors: Comer Brett T. , Kincaid Nathan W. , Smith Nathan J. , Wallace James H. , Kountakis Stilianos E.
Published: July 2013

Objectives/Hypothesis

This study is undertaken to determine if the presence or absence of multiseptated frontal sinuses is associated with the presence or absence of supraorbital ethmoid cells (SOECs).

Study Design

Analysis of prospectively collected data.

Methods

Sixty consecutive patients with chronic rhinosinusitis were identified from a prospectively collected database at a tertiary‐referral institution as having full‐sinus computed tomography (CT) scans. Preoperative or initial CT scans of the sinuses were reviewed, specifically identifying the presence or absence of supraorbital ethmoid air cells (SOECS) and frontal sinus multiseptated sections on coronal imaging. Statistical analysis was performed using the chi‐squared test to evaluate any association between the two structural entities.

Results

Sixty total patients were identified, for a total of 120 sides. Of the 61 sides with frontal septations, 43 (70%) had SOECs present and 18 (30%) did not. Of the 59 sides without frontal sinus septations, 13 (22%) had SOECs present and 46 (78%) did not (chi squared = 28.3; P = 0.0000001). The difference in the presence of supraorbital ethmoid cells between whites and blacks is also statistically significant (chi squared = 4.23; P = 0.040).

Conclusion

The presence of frontal sinus septations appears to be significantly associated with and predictive of the presence of supraorbital ethmoid cells. Thus, identifying frontal sinus septations on sinus CT is implicated with more complex anatomy of the frontal recess.

Level of Evidence

NA. Laryngoscope, 123:2090–2093, 2013
Severe systemic reaction from calcium hydroxylapatite vocal fold filler
Authors: Cohen Justin C. , Reisacher William , Malone Melanie , Sulica Lucian
Published: July 2013

We describe a severe systemic reaction that occurred following injection augmentation with calcium hydroxylapatite vocal fold filler. The reaction occurred within 30 minutes of the procedure and consisted of diffuse itching, hives, edematous face and eyelids, and voice changes indicating glottic edema. It is classified as a grade 3 systemic reaction. Consideration is given to possible etiologies and at risk patients are discussed. We recommend a postprocedure observation time of at least 30 minutes to monitor for such reactions. Laryngoscope, 123:2237–2239, 2013
Glycosylation of Polyphosphazene Nanofibrous Membrane by Click Chemistry for Protein Recognition
Authors: Qian Yue‐Cheng , Ren Ning , Huang Xiao‐Jun , Chen Chen , Yu An‐Guo , Xu Zhi‐Kang
Published: July 2013

A novel core/sheath glycosylated polyphosphazene nanofibrous membrane for use in protein recognition is fabricated via coaxial electrospinning process with alkyl polyphosphazene as the sheath and polyacrylonitrile (PAN) as the core, followed by introduction of saccharide residues to the surface of the polyphosphazene nanofibrous membrane using alkyne–azide “click” chemistry. A glucose/protein binding assay effectively demonstrates that this nanofibrous membrane can selectively recognize Con A while showing almost no binding with bovine serum albumin (BSA). Furthermore, the affinity capability of proteins (BSA and Con A) for the glycosylated polyphosphazene surface is investigated quantitatively using a surface plasmon resonance (SPR) technique.

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The Molar Mass Distribution of Polymers in Step‐Growth Polymerization is Influenced by Cyclization Reactions. The Simplified Case of Irreversible Reactions with Cyclizations is Independent of the Ring Size
Authors: Szymanski Ryszard
Published: July 2013

There were derived equations describing kinetics of the step‐growth polymerization (SGP) proceeding in parallel with cyclization. Only a simplified case of irreversible reactions and cyclization involving terminal functional groups of linear polymer, with the rate independent of ring‐size was analyzed. The analytical solutions for all main features of the SGP were obtained. The linear polymer exhibits the most probable distribution and attains its limited maximum degree of polymerization before vanishing at complete conversion due to cyclization. The eventual cyclic polymer has lower degree of polymerization than linear one and much broader distribution.
Screening of CACNA1A and ATP1A2 genes in hemiplegic migraine: clinical, genetic, and functional studies
Authors: Carreño Oriel , Corominas Roser , Serra Selma Angèlica , Sintas Cèlia , Fernández‐Castillo Noèlia , Vila‐Pueyo Marta , Toma Claudio , Gené Gemma G. , Pons Roser , Llaneza Miguel , Sobrido María‐Jesús , Grinberg Daniel , Valverde Miguel Ángel , Fernández‐Fernández José Manuel , Macaya Alfons , Cormand Bru
Published: July 2013

Hemiplegic migraine (HM) is a rare and severe subtype of autosomal dominant migraine, characterized by a complex aura including some degree of motor weakness. Mutations in four genes (CACNA1A, ATP1A2, SCN1A and PRRT2) have been detected in familial and in sporadic cases. This genetically and clinically heterogeneous disorder is often accompanied by permanent ataxia, epileptic seizures, mental retardation, and chronic progressive cerebellar atrophy. Here we report a mutation screening in the CACNA1A and ATP1A2 genes in 18 patients with HM. Furthermore, intragenic copy number variant (CNV) analysis was performed in CACNA1A using quantitative approaches. We identified four previously described missense CACNA1A mutations (p.Ser218Leu, p.Thr501Met, p.Arg583Gln, and p.Thr666Met) and two missense changes in the ATP1A2 gene, the previously described p.Ala606Thr and the novel variant p.Glu825Lys. No structural variants were found. This genetic screening allowed the identification of more than 30% of the disease alleles, all present in a heterozygous state. Functional consequences of the CACNA1A‐p.Thr501Met mutation, previously described only in association with episodic ataxia, and ATP1A2‐p.Glu825Lys, were investigated by means of electrophysiological studies, cell viability assays or Western blot analysis. Our data suggest that both these variants are disease‐causing.
Molecular dynamics of (E)‐6‐acetyl‐3‐(2‐hydroxy‐5‐methylphenyl)‐5‐styryl cyclohex‐2‐en‐1‐one and (E)‐6‐ethylcarboxylate‐3‐(2‐hydroxy‐5‐methylphenyl)‐5‐styryl cyclohex‐2‐en‐1‐one in a solution studied by NMR spectroscopy
Authors: Mamedov I. G. , Bayramov M. R. , Mamedova Y. V. , Maharramov A. M.
Published: July 2013

Molecular dynamics of cyclohexenone derivatives of (2E,4E)‐1‐(2‐hydroxy‐5‐methylphenyl)‐5‐phenyl‐2,4‐pentadiene‐1‐one (chalcone) has been investigated in solutions using NMR. The results confirm the formation of O‐H⋯O intramolecular hydrogen bond and the presence of keto–enol tautomeric transitions in the (E)‐6‐acetyl‐3‐(2‐hydroxy‐5‐methylphenyl)‐5‐styryl cyclohex‐2‐en‐1‐one. The free energy of activation for the keto–enol tautomeric transitions has been calculated. The keto–enol tautomerism in the investigated compound has been also confirmed by chemical method. Copyright © 2013 John Wiley & Sons, Ltd.
The future of Facebook fundraising
Authors: Waddingham Jonathan
Published: July 2013

Facebook is the world's largest social network, and charities are keen to create communities and engage with supporters there; yet few are using any of Facebook's tools to raise money effectively. On the basis of data from Facebook and JustGiving, we will learn how to prompt donors to share their donations, the pound value of a Facebook share, and how to generate the best value from shares. We will also reveal Facebook's best practices for community building, explore the trend for Timeline integration and underline the importance of mobile in the future for Facebook fundraising.

Copyright © 2013 John Wiley & Sons, Ltd.
Creation of biofunctionalized plasma polymerized allylamine gradients
Authors: Mangindaan Dave , Kuo Wei‐Hsuan , Kurniawan Hengky , Wang Meng‐Jiy
Published: July 2013

A chemical gradient possessing gradual change of amine concentration for every 100 carbon atoms (NHx/100 C) from 4.03 to 1.98 was prepared by plasma polymerization of allylamine on polypropylene films. Electron spectroscopy for chemical analysis and water contact angle (WCA) measurements revealed that the nitrogen incorporation resulted in the amine functionality (CN binding) and, therefore, the formation of the wettability gradient. The gradient showed the WCAs varied from 15° to 90° as the change of amine concentration on the gradient from the nitrogen rich end to the nitrogen deprived end. Furthermore, the interactions between the gradient with mammalian cells revealed that more than twofold cell density was found at the nitrogen rich end when compared with the nitrogen deprived end. Plasma polymerization was demonstrated as an effective method to create controllable chemical gradient and the obtained allylamine gradient was useful for biomaterial applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1361–1367
A general semiparametric hazards regression model: efficient estimation and structure selection
Authors: Tong Xingwei , Zhu Liang , Leng Chenlei , Leisenring Wendy , Robison Leslie L.
Published: July 2013

We consider a general semiparametric hazards regression model that encompasses the Cox proportional hazards model and the accelerated failure time model for survival analysis. To overcome the nonexistence of the maximum likelihood, we derive a kernel‐smoothed profile likelihood function and prove that the resulting estimates of the regression parameters are consistent and achieve semiparametric efficiency. In addition, we develop penalized structure selection techniques to determine which covariates constitute the accelerated failure time model and which covariates constitute the proportional hazards model. The proposed method is able to estimate the model structure consistently and model parameters efficiently. Furthermore, variance estimation is straightforward. The proposed estimation performs well in simulation studies and is applied to the analysis of a real data set. Copyright © 2013 John Wiley & Sons, Ltd.
Firm litigation risk and the insurance value of corporate social performance
Authors: Koh Ping‐Sheng , Qian Cuili , Wang Heli
Published: July 2013

This paper advances the risk management perspective that superior social performance enhances firm value by serving as an ex ante valuable insurance mechanism. We posit that good social performance is more valuable as an insurance mechanism for firms with higher litigation risks. Moreover, value generation of corporate social performance (CSP) depends on whether a firm has gained pragmatic legitimacy (i.e., a firm's financial health) and moral legitimacy (i.e., whether or not a firm operates in a socially contested industry) among its stakeholders. We find that the value of CSP as insurance against litigation risk is practically significant, adding 2 to 4 percent to firm value. But CSP is less likely to create value if the firm is in financial distress or is operating in socially contested industries. Copyright © 2013 John Wiley & Sons, Ltd.
Paradoxien der Geschichtsschreibung zur Baukonstruktion: Eine kurze Untersuchung am Schabolovskaya‐Sendeturm in Moskau
Authors: Hassler Uta , Nozhova Ekaterina
Published: July 2013

Im August 2013 ist das 160‐jährige Jubiläum des russischen Ingenieurs V. G. Schuchov (1853 –1939). Der Schabolovskaya‐Sendeturm in Moskau, erbaut 1919 bis 1922, gehört zu seinen bekanntesten und am häufigsten zitierten Arbeiten. Es gibt jedoch sehr wenige Informationen über den Bauprozess und die Konstruktion selber, und der Zugang zum Turm ist beschränkt, was eine traditionelle Bauforschung erschwert. Im Rahmen des D‐A‐CH‐Forschungsprojekts “Konstruktionswissen der frühen Moderne – Schuchovs Strategien des sparsamen Eisenbau“ hat eine Gruppe des IDB der ETH Zürich eine Untersuchung des Turms auf der Basis von Archivmaterial durchgeführt. Innerhalb eines kurzen Zeitraums haben die Autoren einige Artefakte am Turm angebracht, die Verbindungen zwischen einer bestimmten Struktur und der Geschichte der russischen Industrialisierung aufzeigen. Der Aufsatz erläutert die verschiedenen Phasen und Methoden der Bauforschung am Schabolovskaya‐Sendeturm und beschreibt das Themenfeld, das die Erforschung industrieller Strukturen zur Interdisziplinarität hinführt.

Paradoxes in construction history: A study of the Schabolovskaya Radio Tower in Moscow, Russia. August of this year marks the 160th anniversary of the birth of Russian engineer V. G. Shukhov (1853–1939). The Schabolovskaya Tower in Moscow, built 1919 to 1922, belongs to his most well‐known and widely cited works. However little is known about its construction and access to the tower is restricted, which creates obstacles for conventional research methods. A group from the IDB at ETH Zurich, acting within the framework of the D‐A‐CH Research Project (Konstruktionswissen der frühen Moderne – Schuchovs Strategien des sparsamen Eisenbaus), has made a new study of the tower, based on archival material and the opportunity of a short investigation of the structure in‐situ. The research group has identified artifacts that help reveal links between this particular structure and the history of Russian industrialization. This article outlines the different stages and methods of construction research employed in the study of the Schabolovskaya Tower and describes the array of themes which continue to push the research of industrial structures towards interdisciplinarity.
Effiziente Dimensionierung von Tragbohlen kombinierter Stahlspundwände
Authors: Kuhlmann Ulrike , Just Adrian , Leitz Bernadette , Grabe Jürgen
Published: July 2013

Dieser Beitrag befasst sich mit der Optimierung der Stabilitätsnachweise nach DIN EN 1993‐1‐1 für die Bemessung von Tragbohlen kombinierter Stahlspundwände. Neben der Berücksichtigung der Bettung der Tragbohlen im umgebenden Boden ist eine weitere Möglichkeit hierbei die Berücksichtigung des Torsionswiderstandes teilverschweißter Doppeltragbohlen. Da für ausreichend torsionssteife Querschnitte Biegedrillknicken im Nachweis nicht berücksichtigt werden muss, kann der Stabilitätsnachweis durch Ansatz eines wegen der Teilverschweißung erhöhten Torsionswiderstandes ggf. deutlich vereinfacht werden. Zur Bestimmung der tatsächlichen Torsionssteifigkeit wurden sechs Versuche an zwei großformatigen Tragbohlen mit je drei Verschweißungsgraden durchgeführt. Auf der Basis eines numerischen Modells wurden die Versuchsergebnisse nachvollzogen und eine Parameterstudie durchgeführt. An einem konkreten Beispiel wird gezeigt, wie durch Berücksichtigung einer Teilverschweißung eine effiziente Dimensionierung der Tragbohlen kombinierter Stahlspundwände möglich ist.

Efficient verification of king piles of combined steel sheet walls. This contribution deals with the optimization of the stability verification according to DIN EN 1993‐1‐1 for the design of combined steel walls built‐up by H‐sections as king‐piles and infill steel sheeting. In addition to the king piles’ embedment in the soil advantage can be taken from the torsional stiffness of partially welded double king piles. Since lateral torsional buckling does not need to be considered for cross sections with a sufficient torsional stiffness, it is possible to simplify the stability verification significantly by considering the partial welding and the resulting increased torsional stiffness. In order to determine the real torsional stiffness, two large‐sized king piles with three degrees of welding were tested. Based on a numerical model the test results were simulated and a parameter study was carried out. For a given example it is shown how the consideration of partial welding allows an efficient design verification of the king piles.
Schrägseilbrücke mit Litzenbündelseilen: Elbebrücke Schönebeck – Ausführungsplanung (Teil 2)
Authors: Anistoroaiei Christian , Heymel Ulrich , Jung Rolf , Sagner Erik
Published: July 2013

Die Schrägseilbrücke überspannt den Elbestrom mit einer freien Stützweite von 185 m. Das gut sichtbare Merkmal der Brücke ist der über 73 m hohe A‐Pylon. Die Vorlandbereiche werden linkselbisch mit 16 und rechtselbisch mit 8 weiteren Feldern überquert.

Für den insgesamt 1128 m langen Brückenzug wurden die unterschiedlichsten Bauweisen vorteilhaft miteinander kombiniert und ausgeführt.

Nachdem im Stahlbau Heft 3/2013 bereits schwerpunktmäßig über die Ausführung des Stahlbaus und der Litzenseile berichtet wurde, sollen in diesem Beitrag die Detailplanung und die statischen Besonderheiten mit ihrem Bezug zur Herstellung im Mittelpunkt stehen.

A cable stayed bridge with parallel strand cables: Elbe Bridge Schönebeck (Germany) – Detailed Design (part 2). The cable stayed bridge crosses the River Elbe with a main span of 185 m. The main feature of this bridge is the A‐shaped, about 73 m high pylon. The foreshore areas are crossed by 16 additional spans on the left side and 8 additional spans on the right side of the river. For the bridge with its total length of 1128 m different methods of construction were used.

The publication part 1 “Stahlbau Heft 3/2013” contains the construction of the bridge and the stay cables. This part 2 contains the detail design and static aspects in respect of construction.
Bioengineered nanoparticles for siRNA delivery
Authors: Kozielski Kristen L. , Tzeng Stephany Y. , Green Jordan J.
Published: July 2013

Short interfering RNA (siRNA) has been an important laboratory tool in the last two decades and has allowed researchers to better understand the functions of nonprotein‐coding genes through RNA interference (RNAi). Although RNAi holds great promise for this purpose as well as for treatment of many diseases, efforts at using siRNA have been hampered by the difficulty of safely and effectively introducing it into cells of interest, both in vitro and in vivo. To overcome this challenge, many biomaterials and nanoparticles (NPs) have been developed and optimized for siRNA delivery, often taking cues from the DNA delivery field, although different barriers exist for these two types of molecules. In this review, we discuss general properties of biomaterials and nanoparticles that are necessary for effective nucleic acid delivery. We also discuss specific examples of bioengineered materials, including lipid‐based NPs, polymeric NPs, inorganic NPs, and RNA‐based NPs, which clearly illustrate the problems and successes in siRNA delivery. WIREs Nanomed Nanobiotechnol 2013. doi: 10.1002/wnan.1233

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Emerging Technologies

Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease