bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical application of massively parallel sequencing‐based prenatal noninvasive fetal trisomy test for trisomies 21 and 18 in 11 105 pregnancies with mixed risk factors
Authors: Dan Shan , Wang Wei , Ren Jinghui , Li Yali , Hu Hua , Xu Zhengfeng , Lau Tze Kin , Xie Jianhong , Zhao Weihua , Huang Hefeng , Xie Jiansheng , Sun Luming , Zhang Xiaohong , Wang Weipeng , Liao Shixiu , Qiang Rong , Cao Jiangxia , Zhang Qiufang , Zhou Yulin , Zhu Haiyan , Zhong Mei , Guo Yi , Lin Linhua , Gao Zhiying , Yao Hong , Zhang Hongyun , Zhao Lijian , Jiang Fuman , Chen Fang , Jiang Hui , Li Songgang , Li Yingrui , Wang Jun , Wang Jian , Duan Tao , Su Yue , Zhang Xiuqing
Published: November 2012

Objective

To report the performance of massively parallel sequencing (MPS) based prenatal noninvasive fetal trisomy test based on cell‐free DNA sequencing from maternal plasma in a routine clinical setting in China.

Method

The MPS‐based test was offered as a prenatal screening test for trisomies 21 and 18 to pregnant women in 49 medical centers over 2 years. A total of 11 263 participants were recruited and the MPS‐based test was performed in 11 105 pregnancies. Fetal outcome data were obtained after the expected date of confinement.

Results

One hundred ninety cases were classified as positive, including 143 cases of trisomy 21 and 47 cases of trisomy 18. With the karyotyping results and the feedback of fetal outcome data, we observed one false positive case of trisomy 21, one false positive case of trisomy 18 and no false negative cases, indicating 100% sensitivity and 99.96% specificity for the detection of trisomies 21 and 18.

Conclusion

Our large‐scale multicenter study proved that the MPS‐based test is of high sensitivity and specificity in detecting fetal trisomies 21 and 18. The introduction of this screening test into a routine clinical setting could avoid about 98% of invasive prenatal diagnostic procedures. © 2012 John Wiley & Sons, Ltd.
Rapid aneusomy detection in products of conception using the KaryoLite™ BACs‐on‐Beads™ assay
Authors: Paxton Christian N. , Brothman Arthur R. , Geiersbach Katherine B.
Published: November 2012

Objective

Chromosome analysis is the traditional method for detecting genetic abnormalities in products of conception, but it is prone to a high failure rate because of the requirement for cell culture. Molecular genetic tests do not require cell culture, but are either more expensive (e.g. chromosomal microarray) or less sensitive than chromosome analysis (e.g. fluorescence in situ hybridization, multiplex ligation mediated amplification). The KaryoLite™ BACs‐on‐Beads™ (KL‐BoBs™) assay is highly multiplexed with low resolution coverage and is designed to detect aneusomy for any chromosome.

Methods

We retrospectively tested 100 products of conception samples previously characterized by karyotype (n = 90), and/or microarray (n = 61) using KL‐BoBs™. We included samples extracted from either cultured or direct specimens from placental villi or fetal somatic tissue, with a variety of chromosomal abnormalities typically identified in our clinical cytogenetics laboratory.

Results

KL‐BoBs™ and microarray results were concordant for all cases of aneusomy. On the basis of a review of 3794 consecutive cases in our laboratory, aneusomy accounts for 74.3% of abnormalities detected. Polyploidy and structural abnormalities were not detected by KL‐BoBs™.

Conclusion

KL‐BoBs™ is potentially very useful as a first line test for aneusomy detection because of its lower cost, rapid detection, and ability to generate a molecular karyotype for samples that fail to grow in culture. © 2012 John Wiley & Sons, Ltd.
Environmental allergies and respiratory morbidities in cystic fibrosis
Authors: Collaco Joseph M. , Morrow Christopher B. , Green Deanna M. , Cutting Garry R. , Mogayzel Peter J.
Published: November 2012

Background

Cystic fibrosis (CF) is characterized by recurrent respiratory infections and progressive lung disease. Although environmental factors account for 50% of the variation in CF lung function, few specific exposures have been identified. Studies using small study samples focusing on environmental allergies in CF have had inconsistent results. Our objective was to examine the role of environmental allergies in upper and lower respiratory tract morbidities in CF.

Methods

A total of 1,321 subjects with CF were recruited through the U.S. CF Twin–Sibling Study. Questionnaires were used to determine the presence/absence of environmental allergies. Questionnaires, chart review, and U.S. CF Foundation Patient Registry data were used to track outcomes.

Results

Within the study sample 14% reported environmental allergies. Environmental allergies were associated with a higher risk of sinus disease (adjusted OR: 2.68; P < 0.001) and nasal polyps (adjusted OR: 1.74; P = 0.003). Environmental allergies were also associated with a more rapid decline in lung function (additional −1.1%/year; P = 0.001). However, allergies were associated with a later median age of acquisition of Pseudomonas aeruginosa (6.6 years vs. 4.4 years; log rank P = 0.027). The reported use of common allergy medications, anti‐histamines and leukotriene inhibitors, did not alter the frequency of respiratory morbidities.

Conclusions

Environmental allergies are associated with an increased risk of sinus disease and nasal polyps and a more rapid decline in CF lung function, but may have a protective effect against the acquisition of P. aeruginosa. Prospective studies are needed to confirm these associations which have implications for more aggressive management of allergies. Pediatr Pulmonol. 2013; 48:857–864. © 2012 Wiley Periodicals, Inc.
Obesity in children with poorly controlled asthma: Sex differences
Authors: Lang Jason E. , Holbrook Janet T. , Wise Robert A. , Dixon Anne E. , Teague W. Gerald , Wei Christine Y. , Irvin Charles G. , Shade David , Lima John J. ,   for the American Lung Association‐Asthma Clinical Research Centers
Published: November 2012

Background

Obesity increases asthma risk, and may alter asthma severity. In adults, sex appears to modify the effect of obesity on asthma. Among children, the effect of sex on the relationship between obesity and asthma severity remains less clear, particularly when considering race.

Objective

To determine how obesity affects disease characteristics in a diverse cohort of children with poorly controlled asthma, and if obesity effects are altered by sex.

Design

We analyzed 306 children between 6 and 17 years of age with poorly controlled asthma enrolled in a 6‐month trial assessing lansoprazole for asthma control. In this secondary analysis, we determined associations between obesity and symptom severity, spirometry, exacerbation risk, airway biomarkers, bronchial reactivity, and airflow perception. We used both a multivariate linear regression and longitudinal mixed‐effect model to determine if obesity interacted with sex to affect asthma severity.

Results

Regardless of sex, BMI >95th percentile did not affect asthma control, exacerbation risk or airway biomarkers. Sex changed the effect of obesity on lung function (sex × obesity FEV1%, interaction P‐value < 0.01, sex × obesity FEV1/FVC, interaction P‐value = 0.03). Obese males had significantly worse airflow obstruction compared to non‐obese males, while in females there was no obesity effect on airflow obstruction. In females, obesity was associated with significantly greater FEV1 and FVC, and a trend toward reduced airway reactivity.

Conclusions

Obesity did not affect asthma control, airway markers or disease stability; however obesity did affect lung function in a sex‐dependent manner. In males, obesity associated with reduced FEV1/FVC, and in females, obesity associated with substantially improved lung function. Pediatr Pulmonol. 2013; 48:847–856. © 2012 Wiley Periodicals, Inc.
Structural basis of fluorescence quenching in caspase activatable‐GFP
Authors: Nicholls Samantha B. , Hardy Jeanne A.
Published: November 2012

Apoptosis is critical for organismal homeostasis and a wide variety of diseases. Caspases are the ultimate executors of the apoptotic programmed cell death pathway. As caspases play such a central role in apoptosis, there is significant demand for technologies to monitor caspase function. We recently developed a caspase activatable‐GFP (CA‐GFP) reporter. CA‐GFP is unique due to its “dark” state, where chromophore maturation of the GFP is inhibited by the presence of a C‐terminal peptide. Here we show that chromophore maturation is prevented because CA‐GFP does not fold into the robust β‐barrel of GFP until the peptide has been cleaved by active caspase. Both CA‐GFP and GFP1‐10, a split form of GFP lacking the 11th strand, have similar secondary structure, different from mature GFP. A similar susceptibility to proteolytic digestion indicates that this shared structure is not the robust, fully formed GFP β‐barrel. We have developed a model that suggests that as CA‐GFP is translated in vivo it follows the same folding path as wild‐type GFP; however, the presence of the appended peptide does not allow CA‐GFP to form the barrel of the fully matured GFP. CA‐GFP is therefore held in a “pro‐folding” intermediate state until the peptide is released, allowing it to continue folding into the mature barrel geometry. This new understanding of the structural basis of the dark state of the CA‐GFP reporter will enable manipulation of this mechanism in the development of reporter systems for any number of cellular processes involving proteases and potentially other enzymes.
Structural insight into the separate roles of inositol tetraphosphate and deacetylase‐activating domain in activation of histone deacetylase 3
Authors: Arrar Mehrnoosh , Turnham Rigney , Pierce Levi , de Oliveira Cesar Augusto F. , McCammon J. Andrew
Published: November 2012

Histone deacetylases (HDACs) repress transcription by deacetylating acetyllysines on specific histone tails. HDAC3 is implicated in neurodegenerative diseases, certain leukemias, and even in disrupting HIV‐1 latency. A recent crystal structure of HDAC3 in complex with the deacetylase‐activating domain (DAD) of its corepressor complex revealed an inositol tetraphosphate (IP4) molecule at the protein–protein interface. IP4 was shown to play an important, yet mechanistically ambiguous, role in the activity of HDAC3. The goal of this article is to explore the conformational ensemble of HDAC3 in its inactive apo state and in the presence of each or both of DAD and IP4. Using triplicate, 100 ns molecular dynamic simulations, we study the apo, ternary, and intermediate DAD‐bound or IP4‐bound HDAC3 states. We find that a population‐shift effect is induced by the presence of each corepressor, and is most notable in the presence of both. Our results offer new insights into the change in dynamics necessary for the activation of HDAC3 and highlight the roles of IP4 and DAD in this process.
Age‐dependent racemization of serine residues in a human chaperone protein
Authors: Hooi Michelle Y. S. , Raftery Mark J. , Truscott Roger J. W.
Published: November 2012

Racemization is one of the most abundant modifications in long‐lived proteins. It has been proposed that the accumulation of such modifications over time could lead to changes in tissues and ultimately human age‐related diseases. Serine is one of the main amino acids involved in racemization; however, the site of D‐Ser in any aged protein has yet to be reported. In this study, racemization of two residues, Ser 59 and Ser 62, has been demonstrated in an unstructured region of the small heat shock protein, αA‐crystallin. αA‐crystallin is also the most abundant structural protein in the human lens. D‐Ser increased linearly with age in normal lenses, until it accounted for approximately 35% of the Ser at both sites by the age of 75 years. In agreement with a possible role in human age‐related disease, levels were significantly higher in cataract lenses. It is likely that such prevalent age‐related changes contribute to the denaturation of α‐crystallin, and therefore its ability to act as a chaperone. Racemization of amino acids, such as serine, in flexible regions of long‐lived proteins, could be associated with the development of human age‐related conditions such as cataract.
Comparative surface studies of oxygen passivated FeCo nanoparticles and thin films
Authors: Jaffari G. Hassnain , Lin H. , Rumaiz A. K. , Yassitepe Emre , Ni C. , Shah S. Ismat
Published: November 2012

We present results on the comparative studies of the surfaces of oxygen passivated FeCo nanoparticles (NPs) and thin films prepared by inert gas condensation and pulse laser deposition, respectively. Morphology and structure of the NPs and thin films are investigated by transmission electron microscopy (TEM) and X‐ray diffraction. Due to the larger surface area, thicker oxide over‐layer is observed for particles in comparison with thin films. X‐ray photoelectron spectroscopy (XPS) spectra strongly depended on the morphology and oxide over layer thicknesses for nanostructures. This leads to observation of clearly different background and is explained in term of different cationic distribution in the overlayer, thicknesses, and morphology (enhanced surface area) of the nanostructures. TEM analyses showed an oxide over‐layer on the NP of approximately 2.6 nm, which is consistent with the theoretical model based on electron attenuation lengths. However, in the case of thin films a much thinner oxide over‐layer of about 1.3 nm was observed. As expected, XPS spectra of oxygen passivated particles show oxide peaks with weak metal peaks compared to oxygen passivated thin films which show significantly high zero‐valent metal peaks.
Electronic band structure of helical iodine chains
Authors: Rybkovskiy Dmitry , Osadchy Alexander , Obraztsova Elena
Published: November 2012

The electronic band structure of helical iodine chains was calculated within the empirical tight binding approach. The screw symmetry of the system was used to reduce the size of the problem to a single atom with four atomic orbitals. The overlap parameters were fitted to reproduce the DFT results for a linear iodine chain. The obtained results for helical chains have shown the energy band splitting due to the overlap between p orbitals introduced by the structure twisting. The splitting magnitude depends on the pitch of the helix.
Carbon solubility in nickel nanoparticles: A grand canonical Monte Carlo study
Authors: Diarra Mamadou , Amara Hakim , Ducastelle François , Bichara Christophe
Published: November 2012

Producing single‐wall carbon nanotubes with a given structure, in terms of diameter and chirality, is still a difficult issue. In this context, understanding the physical and chemical properties of the catalyst nanoparticle during the chemical vapor deposition synthesis is fundamental. By using tight‐binding calculations at atomic scale, we show that carbon solubility is larger for smaller nanoparticles (NPs), with solubility limits depending on the size, but also on the physical state (solid, partially molten liquid) of the catalyst. Moreover, optimal thermodynamic conditions have been found to nucleate carbon cap after saturation of the metal catalyst with carbon atoms.

magnified image

Density profiles along the radius of the nanoparticle calculated at 1000 K (black: C, orange: Ni). The inset presents the structure of C‐rich NPs with a crystalline core surrounded by a molten layer.
Catalyst design by cyclic deposition: Nanoparticle formation and growth of high‐density nanotube forests
Authors: Esconjauregui Santiago , Fouquet Martin , Xie Rongsie , Cartwright Richard , Newcomb Simon B. , Robertson John
Published: November 2012

The areal density of carbon nanotube forests can be increased up to the order of 1013 cm−2 using cycles of deposition and annealing of ultra‐thin metal films, followed by nanoparticle immobilization. Herein, we show how the density of the catalyst nanoparticles increases after each cycle by using cross‐sectional transmission electron microscopy. The layers of metal catalyst – subsequently deposited after previous annealing – sit on the uncovered areas of the support and, after annealing, restructure into nanoparticles cumulatively increasing the catalyst density. These nanoparticles lead to close‐packed, high‐density nanotube forests with nanotube areal densities of ∼1013 cm−2. The height of these high‐density forests shortens as the density of the catalyst nanoparticle increases, which is observed using several synthesis conditions. This high nanotube density is required for using carbon nanotubes as interconnects in integrated circuits and in thermal interface materials.
De‐intercalation process from Stage‐1 to Stage‐2 graphite intercalation compounds revisited
Authors: Chacón‐Torres J. C. , Ganin A. Y. , Rosseinsky M. J. , Pichler T.
Published: November 2012

The identification and contribution of the different phonons present in the G‐line Raman response in Stage‐1 and Stage‐2 graphite intercalation compounds (GIC) is crucial for a correct stage determination. Different factors like laser induced de‐intercalation play an important role in the precise stage assignment of these phases, and their intrinsic Raman response. In this contribution, an in situ micro‐Raman analysis was conducted under high‐vacuum conditions. Local heating of the samples was induced by using a high laser power (8.5 mW) in order to study the de‐intercalation process from Stage‐1 to Stage‐2 GICs. A detailed Raman line‐shape analysis was performed from the recorded spectra to determine the changes from the G‐line response of KC8, CaC6, and LiC6. We confirmed the assignment of the broad E2g Fano mode at ∼1510 cm−1 to the intrinsic Stage‐1 Raman response in GICs. Additionally, the most evident change from Stage‐1 to Stage‐2 was observed in an asymmetric Fano mode in the range of 1565–1610 cm−1. This mode is linked to the first‐order stretching Raman mode of Graphite, which tends to increase in frequency and decrease in width as function of de‐intercalation. Finally, the response of the Stage‐2 phase after de‐intercalation was confirmed to be a useful benchmark for the identification of the intercalation stage in highly doped GICs.
Designing a spiropyran‐based molecular switch for carbon nanotube functionalization: Influence of anchor groups and tube–switch separation
Authors: Bluemmel Pascal , Setaro Antonio , Maity Chandan , Hecht Stefan , Reich Stephanie
Published: November 2012

Molecular switch compounds, consisting of aromatic anchoring groups connected to a spiropyran moiety, are exploited for carbon nanotube functionalization. The effect of the different anchor groups on sample distribution and debundling efficiency is investigated as well as the influence of the anchor–switch distance and hence tube–switch separation. Morphologically similar anchor groups result in similar chiral compositions of the sample. With smaller separation, the tube–switch interaction strength increases as well as the lifetime of the ring opened isomer.
Relaxation dynamics via acoustic phonons in carbon nanotubes
Authors: Köhler Christopher , Watermann Tobias , Malic Ermin
Published: November 2012

We have investigated the efficiency of scattering processes through acoustic phonons in semiconducting nanotubes. Based on the density matrix formalism we obtain Boltzmann scattering equations, which give us a microscopic access to the time‐ and momentum‐resolved relaxation dynamics of optically excited carriers. In agreement with a recent experiment [see Dyatlova et al., Nano Lett. 12, 2249 (2012)], we obtain relaxation times on the picosecond time scale. Here we study the importance of carrier–phonon interaction as a function of probe energy and initial temperature for the exemplary (8,7) nanotube. Furthermore, we calculate the relaxation dynamics for nanotubes with different diameters focusing on the change in the relaxation time with the curvature of the corresponding energetically lowest conduction subband.
Ferromagnetic decoration in metal–semiconductor separated and ferrocene functionalized single‐walled carbon nanotubes
Authors: Chernov A. , Havlicek M. , Jantsch W. , Rümmeli M. H. , Bachmatiuk A. , Yanagi K. , Peterlik H. , Kataura H. , Sauerzopf F. , Resel R. , Simon F. , Kuzmany H.
Published: November 2012

Spin resonance, magnetic measurements, and structural analysis are reported for metal‐semiconductor separated SWCNTs after filling with ferrocene. Raman scattering performed after a heat treatment confirms partial transformation to double‐walled CNTs but results from spin resonance (FMR), X‐ray diffraction, and TEM evidence in addition the growth of ferromagnetic nanoparticles. For the metallic tubes the particles are identified as magnetite (Fe3O4) with full chemical stoichiometry. From the temperature dependence of the FMR response and from measurements of the magnetization by dc and ac SQUID the magnetite crystals are shown to undergo a Verwey transition. The transition temperature from the SQUID experiment is around 125 K as expected but considerably higher than observed from the FMR analysis. Results for semiconducting tubes are similar but magnetic particles are an order of magnitude smaller and exhibit different structures in addition to magnetite.
A detailed analysis of the Raman spectra in superconducting boron doped nanocrystalline diamond
Authors: Szirmai Péter , Pichler Thomas , Williams Oliver A. , Mandal Soumen , Bäuerle Christopher , Simon Ferenc
Published: November 2012

The light scattering properties of superconducting (Tc ≈ 3.8 K) heavily boron doped nanocrystalline diamond has been investigated by Raman spectroscopy using visible excitations. Fano type interference of the zone‐center phonon line and the electronic continuum was identified. Lineshape analysis reveals Fano lineshapes with a significant asymmetry (q ≈ −2). An anomalous wavelength dependence and small value of the Raman scattering amplitude is observed in agreement with previous studies.
Raman investigation of few‐layer graphene on different substrate structures
Authors: Lee Jong‐Kwon , Yamazaki Shiro , Kim Do‐Hyun , Kim Gyu‐Tae , Dettlaff‐Weglikowska Urszula , Roth Siegmar
Published: November 2012

We report Raman analysis of few‐layer graphene (FLG) transferred on flat and patterned substrate structures. These different surface structures created by patterning an area of a Si‐substrate produce differences in the interaction between FLG and the substrate surface. The topography measurement performed by scanning tunneling potentiometry shows that the FLG on the patterned substrate was deformed periodically with 3–4 nm depth variation. Raman spectroscopy reveals that two important features related to the G‐ and 2D‐modes in graphitic structures show different sensitivity to the interaction with the substrate for single‐layer graphene (SLG), FLG, and graphite. Whereas SLG and FLG placed on the patterned substrate demonstrate a strong shift of both 2D‐ and G‐peaks to lower frequencies with respect to the flat part, the multilayer graphene in a graphite flake shows almost no difference between patterned and non‐patterned substrates. We identified the origin of the observed changes in the Raman spectra of SLG and FLG as effects created by the underlying substrate. Especially, substrate induced periodic strain and surface interaction were taken into account to interpret the results.
Hybrid InGaN/CdZnO quantum well structures for optoelectronic applications in the short wavelength spectral region
Authors: Park Seoung‐Hwan , Ahn Doyeol
Published: November 2012

Spontaneous emission characteristics of hybrid InxGa1 − xN/Cd0.05Zn0.95O quantum well (QW) structures were theoretically investigated by using multi‐band effective mass theory. The transition wavelength of the InGaN/CdZnO QW structure is shown to be changed from 415 to 580 nm when the In content x is varied from 0.1 to 0.3. The conventional InGaN/GaN QW structure shows that its peak intensity linearly decreases with increasing peak wavelength. On the other hand, the InGaN/CdZnO QW structure shows that the spontaneous emission coefficient reaches a maximum at around the peak wavelength of 0.484 µm, which corresponds to x = 0.2. This can be explained by the fact that, in a range of the short peak wavelengths, the InGaN/CdZnO QW structure has a very shallow potential well. In a range of the longer peak wavelengths above 0.47 µm, the InGaN/CdZnO QW structure is expected to have a larger spontaneous emission peak than the InGaN/GaN QW structure. This can be explained by the fact that the former has a reduced internal field compared to the latter.
Compensation effect and magnetostriction in CoCr2−xFexO4
Authors: Zhang Hong‐guo , Wang Weng‐hong , Liu En‐ke , Tang Xiao‐dan , Li Gui‐jiang , Zhang Hong‐wei , Wu Guang‐heng
Published: November 2012

The magnetic compensation and magnetostriction properties in Fe‐doped CoCr2O4 samples have been investigated. Structural and magnetic measurements imply that the doped Fe3+ ions initially occupy the B1 (Cr) sites when x < 0.1, and then mainly take the A (Co) sites. This behaviour results in a role conversion of magnetic contributors and a composition compensation between two competitively magnetic sublattices at x = 0.1. Temperature‐dependent compensation has also been found in the samples with x = 0.1–0.22, with the compensation temperature in the range of 40–104 K. The Fe3+ doping also modulates the exchange interaction of the system and prevents the formation of long‐range conical order of spins. The magnetoelectric transition temperature at 23 K in CoCr2O4 is shifted to lower temperature by increasing the dopants. The magnetostriction effect in this system has been observed for the first time. The strain has a maximum value of about 280 ppm at x = 0.4. The magnetostriction is consistent with the behaviour of the two magnetic compensations.
Carrier transport and charge transfer properties in coumarin‐doped bulk‐heterojunction materials
Authors: Watanabe T. , Maeda T. , Yamashita K. , Yanagi H.
Published: November 2012

We have investigated photovoltaic properties of organic solar cells using polymer‐fullerene bulk‐heterojunction films doped with coumarin dyes. Whereas the coumarin molecules used in this study had similar absorption bands, evident difference was observed in the open‐circuit voltage as well as in the short‐circuit current. In particular, the doping of coumarin 307 was found to cause a distinct enhancement in the open‐circuit voltage. On the other hand, the doping of coumarin 30 gave a serious degradation in the device performance. These results were strongly associated with calculated molecular energies of the doped dyes, especially with the highest occupied molecular orbital energy. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Roles of binding energy and diffusion length of singlet and triplet excitons in organic heterojunction solar cells
Authors: Narayan Monishka Rita , Singh Jai
Published: November 2012

The influence of binding energy and diffusion length on the dissociation of excitons in organic solids is studied. The binding energy and excitonic Bohr radius of singlet and triplet excitons are calculated and compared using the dissociation energy of 0.3 eV, which is provided by the lowest unoccupied molecular orbital offset in heterojunction organic solar cells. A relation between the diffusion coefficient and diffusion length of singlet and triplet excitons is derived using the Förster and Dexter transfer processes and are plotted as a function of the donor‐acceptor separation. The diffusion length reduces nearly to a zero if the distance between donor and acceptor is increased to more than 1.5 nm. It is found that the donor‐acceptor separation needs to be ≤ 1.5 nm for easy dissociation on singlet excitons leading to better conversion efficiency in heterojunction organic solar cells. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Relaxation time distribution of distant‐pair recombination: Application to QFRS of PL in a‐Si:H
Authors: Aoki Takeshi , Ikeda Kosuke
Published: November 2012

The distribution function of relaxation time of distant‐pair (DP), or nongeminate recombination is derived in an analytic form from the existing theories of DP recombination to analyse the data of quadrature frequency resolved spectroscopy (QFRS) of photoluminescence (PL) in a‐Si:H with the competing recombination model. The distribution function has a single parameter of metastable carrier density n and yields too narrow QFRS spectrum to fit the experimental data. This is improved with introducing the fluctuation Δ of the electron localisation radius ae. The devised formula is demonstrated to predict the dependence of the DP recombination on the photogeneration rate and the defect density in the QFRS data of the high‐quality and defective a‐Si:H. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optoelectronic and thermal properties of solution‐based graphene thin films
Authors: Bauld Reg , Shafiq Ahmed M. , Fanchini Giovanni
Published: November 2012

In this paper we review some of the relationships existing between the optical properties, electrical conductivity, and thermal conductivity in graphene based transparent and conducting thin films. We provide a set of tools that are useful to identify the optimal trade‐off between transmittance and electrical conductivity in these films. In addition we present a set of thermal conductivity measurements of graphene thin films and relate them to the electrical properties in order to build a comprehensive picture of the electrical, thermal, and optical properties of graphene based thin films (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
White polymer light‐emitting diodes co‐doped with phosphorescent iridium complexes bearing the same cyclometalated ligand
Authors: Ikawa Shigeru , Yagi Shigeyuki , Maeda Takeshi , Nakazumi Hiroyuki
Published: November 2012

In order to develop white organic light‐emitting devices, we fabricated poly(9‐vinylcarbazole)‐based polymer light‐emitting diodes (PLEDs) using blue‐ and orange‐phosphorescent bis‐cyclometalated iridium(III) complexes Ir‐1a and Ir‐1b as emitting co‐dopants, both of which possess the same cyclometalated ligand. The PLED co‐doped with Ir‐1a and Ir‐1b in a single emitting layer (WPLED‐1) yielded the optimized white electroluminescence with a Commission Internationale de L'Eclairage (CIE) chromaticity coordinate of (0.33, 0.46), although the value of the color rendering index (CRI) was very poor (CRI = 58). Thus, in order to improve the color rendering properties of WPLED‐1, the deep red‐phosphorescent iridium(III) complex Ir‐2 was employed as an additional co‐dopant. In the PLED co‐doped with Ir‐1a, Ir‐1b and Ir‐2 (WPLED‐2), tuning the ratio of the three emitting co‐dopants allowed us to obtain white electroluminescence with high color rendering properties (CRI = 82), where the CIE chromaticity coordinate of (0.38, 0.44) was obtained. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mg‐doped InXGa1‐XN films deposited by reactive rf‐magnetron sputtering
Authors: Itoh Takashi , Kato Yoshinori , Hibino Syun , Katayama Ryuichi , Ohashi Fumitaka , Nonomura Shuichi
Published: November 2012

In order to use as p‐layer material of top cell, Mg‐doped amorphous indium gallium nitride (a‐InXGa1‐XN) films were deposited at room temperature by simultaneous reactive rf‐magnetron sputtering. Mg composition ratio increased from 0 to 0.039 with increasing rf‐power inputted into Mg target from 0 to 10 W. Large change in the In and N composition ratios were not observed by the Mg doping. Dark conductivity increased from 5.57 × 10–7 to 1.26 × 10–3 S/cm with increasing the Mg composition ratio from 0 to 0.039. The activation energy decreased from 0.51 to 0.041 eV with increasing the Mg composition ratio from 0 to 0.039. Based on these results, Mg‐doping in a‐InXGa1‐XN films deposited at room temperature by simultaneous reactive rf‐magnetron sputtering was discussed (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Eu‐concentration dependence of optical and scintillation properties for Eu‐doped SrF2 single crystals
Authors: Kurosawa Shunsuke , Yokota Yuui , Yanagida Takayuki , Yoshikawa Akira
Published: November 2012

Some Eu‐doped scintillators, such as Eu:SrI2, emit around 400‐nm wavelength that originates from 5d‐4f transition of Eu2+, while some Eu‐doped crystals have emissions from Eu3+ (f‐f emission). In this report, effect of Eu‐doping on optical and scintillation properties of SrF2 crystals with Core‐valence luminescence is discussed. The samples had 0.1, 0.2, 0.5, 1.0, and 2.0 mol% of Eu and were grown by an annealing method. As a result, 5D0‐7Fi (i =1, 2) transition (Eu3+) was detected in the SrF2, containing over 0.5 mol% of Eu, while emission from 0.1 and 0.2‐mol% Eu:SrF2 originated from 5d‐4f transition of Eu2+ and Core‐valence luminescence. The light output of SrF2 doped with 0.1, 0.2, 0.5, 1.0 and 2.0 mol% Eu was estimated to be 13,000 ± 1,000, 12,000 ± 1,000, 13,000 ± 2,000, 8,000 ± 1,000 and 7,000 ± 1,000 photons/MeV, respectively. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
End‐of‐life Solutions for Fibre and Bio‐based Packaging Materials in Europe
Authors: Müller Günter , Hanecker Elisabeth , Blasius Kai , Seidemann Constanze , Tempel Lydia , Sadocco Patrizia , Pozo Beatriz Ferreira , Boulougouris Georgios , Lozo Branka , Jamnicki Sonja , Bobu Elena
Published: November 2012

Efficient end‐of‐life solutions play an important role in developing sustainable packaging because they contribute to reducing resource wastage and environmental impact, whilst providing economic and social benefits. This paper briefly reviews current end‐of‐life solutions for fibre and bio‐based materials for packaging in Europe. It also addresses current research in the field, as well as standardization, legislation and socio‐economic aspects related to renewable packaging in Europe. This review focuses on the following groups of packaging materials: paper and board and bioplastics. With this hierarchy, recycling, organic recovery and energy recovery are analysed with regard to the processes and technologies that offer the most sustainable end‐of‐life options. Copyright © 2012 John Wiley & Sons, Ltd.
On downlink power allocation for multiuser variable‐bit‐rate video streaming
Authors: Huang Yingsong , Mao Shiwen , Li Yihan
Published: November 2012

In this paper, we study the problem of power allocation for streaming multiple variable‐bit‐rate (VBR) videos in the downlink of a cellular network. We consider a deterministic model for VBR video traffic and finite playout buffer at the mobile users. The objective is to derive the optimal downlink power allocation for the VBR video sessions, such that the video data can be delivered in a timely fashion without causing playout buffer overflow and underflow. The formulated problem is a nonlinear nonconvex optimization problem. We analyze the convexity conditions for the formulated problem and propose a two‐step greedy approach to solve the problem. We also develop a distributed algorithm based on the dual decomposition technique, which can be incorporated into the two‐step solution procedure. The performance of the proposed algorithms is validated with simulations using VBR video traces under realistic scenarios. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of Elliptical Snorkel on the Decarburization Rate in Single Snorkel Refining Furnace
Authors: Rui Qixuan , Jiang Fang , Ma Zhuang , You Zhimin , Cheng Guoguang , Zhang Jian
Published: November 2012

In the present work, physical model experiments were performed to investigate the effect of elliptical snorkel on the decarburization in single snorkel refining furnace. A round snorkel with the same cross‐section area as the elliptical snorkel was also made for comparison. Bubble behavior was recorded by a high speed video camera in this study. A volumetric mass transfer coefficient kA/V was used to evaluate the decarburization rate. Measurement of the volumetric mass transfer coefficient kA/V was made by means of the carbon dioxide desorption from a NaOH solution. It is found when the plug location is close to the center of the ladle bottom, almost all the bubbles get into the snorkels. However, when the plug location is too far away from the center of ladle bottom, bubbles will escape from the outside of the snorkel. kA/V generally rises with increasing gas flow rate. Moreover, kA/V is increased when the plug is moved from the center to the half radius of the ladle bottom. However, kA/V is decreased when the plug is moved from the half radius of ladle bottom to the ladle sidewall. It is indicated that kA/V for the elliptical snorkel is larger than that for the round one when the plug is located between the center and half radius of ladle bottom. Nevertheless, when the plug is located between the half radius and the ladle sidewall, the kA/V for the elliptical snorkel is smaller than that for the round one.
Numerical and analytical investigations on plain channels in coupled instabilities
Authors: Ungermann Dieter , Brune Bettina , Lübke Sebastian
Published: November 2012

This paper presents numerical and analytical investigations of thin‐walled steel C‐section members subjected to both local and global buckling. The results presented here are based on experimental tests which are dealt with in a previous publication [1]. Numerical calculations using the finite element method are performed to recalculate test results from stub column tests with local buckling and long column tests with coupled local and global buckling failure. These results are analysed using different design procedures based on Eurocode 3. Using modified buckling factors and an approach considering effective stiffness by approximation, it is possible to determine the ultimate buckling loads from tests and numerical investigations efficiently.
The Design of Langqi Min River Bridge, Fuzhou, China
Authors: Zhang Min , Wan Tianbao , Wang Yingliang
Published: November 2012

One key project in the Chinese city of Fuzhou is Langqi Min River Bridge, which connects the business and technology district with downtown Fuzhou. The main bridge is a twin‐pylon cable‐stayed structure with a main span of 680 m and a steel box girder. This paper presents the detailed design features of the bridge, including foundations, anti‐ship collision devices, pylons, steel box girder and stay cables.
The art of major bridge‐building – Hellmut Homberg and his contribution to multiple cable‐stayed spans
Authors: Pelke Eberhard , Kurrer Karl‐Eugen
Published: November 2012

Based on findings from Büchenauer Bridge (1956), the North Elbe Bridge in Hamburg (1963) and the bridge over the Rhine at Leverkusen (1965), Homberg designed and engineered the Friedrich Ebert Bridge across the River Rhine. This was the first bridge in the world with cables that distribute instead of concentrate the load transfer, and thus define the bridge deck as a continuous, elastically supported element and not as a beam on point supports.

After the building of major bridges declined in Germany, Homberg became active in France, and later rounded off his work with multi‐cable‐stayed bridges in the UK. That work resulted in the Queen Elizabeth II Bridge (1991), Homberg’s late magnum opus.

This article contains a complete catalogue of Homberg’s multi‐cable‐stayed bridges and discusses for the first time previously unpublished designs by Homberg. These prove that he had already moved on from the classic cable‐stayed bridge to the general multi‐span cable‐stayed bridge as early as 1963.
Box traps for feral swine capture: A comparison of gate styles in Texas
Authors: Long David B. , Campbell Tyler A.
Published: November 2012

Many different types of traps have been developed to increase feral swine (Sus scrofa) capture efficiency. Though not previously compared, gate styles may influence capture success. Our objectives were to report feral swine capture data from 31 trapping campaigns conducted in 17 counties from 2005 to 2011 in Texas, USA, compare capture rates by demographic category between side‐swing and rooter gates, and evaluate influences of moisture, using the Palmer Drought Severity Index (PDSI), on juvenile capture rates. We trapped feral swine during all months of the year. Our trap configurations were identical with the exception of gate style. Traps had either side‐swing or rooter gates. We captured 1,310 feral swine during 2,424 trap‐nights. We found no differences in capture rates between gate styles for adults, adult males, or adult females. However, we found juvenile capture rates and total capture rates to differ between gate styles. Box traps with rooter gates captured more juveniles, resulting in more total captures than in box traps with side‐swing gates. Partitioned rooter gates are constructed to allow for continual entry after the gate has been tripped; whereas with single‐panel side‐swine gates, continual entry may be more challenging for juvenile animals that lack the size and strength to push through the spring tension. Rooter gates should be considered over side‐swing gates in management programs aimed at overall damage reduction. However, in management or research programs that seek to capture adult feral swine, side‐swing gates may be more appropriate because fewer non‐target juvenile feral swine are captured. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Distribution of Candida in the oral cavity and its differentiation based on the internally transcribed spacer (ITS) regions of rDNA
Authors: Zahir R. A. , Himratul‐Aznita W. H.
Published: November 2012

This study aimed to determine the distribution of Candida species in the oral cavity and differentiate the species based on PCR amplification, including HinfI and MspI digestion, in order to assess the effectiveness of using the rDNA region for species identification. Samples from saliva as well as palate, tongue and cheek mucosa surfaces were collected from 45 individuals, consisting of three groups: periodontal disease patients; denture‐wearers; and the control group. The samples were serially diluted, spread on BHI and YPD agar plates and scored for colony‐forming units (CFUs). Fifteen random candidal colonies were isolated and subjected to genomic DNA extraction, based on glass beads disruption. Four primers were used to amplify regions in the rDNA, and the ITSI‐5.8S‐ITSII PCR product was digested by HinfI and MspI restriction enzymes. The microbial loads on all sites of the denture‐wearers were found to be significantly higher than control, while in the periodontal disease group only the microbial loads on the tongue were significantly higher than control. Meanwhile, there was no significant difference at other sites. The restriction fragment lengths of the clinical samples were compared to those of seven control species, allowing the differentiation of all seven species and the identification of 14 species from the clinical samples. The MspI restriction digest was not able to distinguish between C. albicans and C. dubliniensis, whereas the HinfI digest could not distinguish between C. tropicalis and C. parapsilosis. It was concluded that PCR–RFLP of the candidal rDNA region has potential for species identification. This study demonstrates the potential use of candidal rDNA as a means for identifying Candida species, based on genotype. The results also indicate the possibility of constructing genetic probes that target specific restriction fragments in the ITSI‐5.8S‐ITSII region, enabling swift and precise identification of Candida species. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis, Characterization, and Properties of Few‐layer Metal Dichalcogenides and their Nanocomposites with Noble Metal Particles, Polyaniline, and Reduced Graphene Oxide
Authors: Matte H. S. S. Ramakrishna , Maitra Urmimala , Kumar Prashant , Govinda Rao Bolla , Pramoda K. , Rao C. N. R.
Published: November 2012

Few‐layer graphene‐like sheets of MoS2, WS2, MoSe2 and WSe2 were prepared by employing two methods. The first method uses microwave synthesis in ethylene glycol or water medium and the second method involves laser irradiation of the bulk samples dispersed in dimethylformamide. The few‐layer dichalcogenide samples were characterized by various microscopic and spectroscopic techniques. These graphene mimics show room‐temperature ferromagnetism and exchange bias besides magnetoresistance at room temperature. We have deposited nanoparticles of gold, silver, and platinum on few‐layer WS2 and characterized the nanocomposites. Nanocomposites of MoS2 with reduced graphene oxide show increase in resistivity with increasing amount of MoS2. The polyaniline MoS2 composite prepared by in situ polymerization of aniline in the presence of few‐layer MoS2 shows evidence of polaronic character.
Virtual Fossils: a New Resource for Science Communication in Paleontology
Authors: Rahman Imran A. , Adcock Keith , Garwood Russell J.
Published: November 2012

Computer-aided 3-D reconstruction of fossils, or virtual paleontology, is an increasingly common and powerful technique. It is now regularly used for research in paleontology, yet to date has impacted little on public outreach and science communication; however, it is ideally suited for these purposes, being increasingly cheap and available, dynamic and exciting, and applicable to a range of topics. Here, we provide an introduction to the field, and a case study of its use for a public engagement event. The steps involved in creating such an educational resource are outlined, and include computed tomography scanning, digital visualization, and 3-D printing of fossils. We emphasize the value of virtual fossils for science communication; they allow for diverse learning styles in a variety of topics. In the future, we hope that virtual paleontology will become a mainstay of communicating the history of life, thereby promoting accurate understanding of evolution.
La fracture de verge à Dakar. À propos de 25 cas
Authors: Niang L. , Thiam I. , Ndoye M. , Ouattara A. , Magloire Y. , Jalloh M. , Labou I. , Gueye S. M.
Published: November 2012

Buts

Présenter les caractéristiques épidémiologiques, cliniques et thérapeutiques des fractures de verge dans le service d’urologie-andrologie de l’hôpital général de Grand Yoff de Dakar.

Matériels et méthode

Il s’agit d’une étude descriptive portant sur 25 cas de fracture de verge pris en charge dans le service d’urologie-andrologie de l’hôpital général de Grand Yoff de Dakar entre janvier 2001 et décembre 2011. Les paramètres suivant ont été étudiés: l’âge, la résidence, les antécédents, les données cliniques, les données de l’exploration chirurgicale et les résultats du traitement.

Résultats

En dix ans, 25 cas de fractures de verge ont été enregistrés soit une moyenne de 2,5 cas par an. L’âge moyen de survenue était de 36 ans avec des extrêmes de 22 et 60 ans. Les circonstances de survenue sont dominées par les manipulations forcées (52 %) et les rapports sexuels (32 %). La douleur associée à une latérodéviation controlatérale de la verge, une tuméfaction localisée de la verge ou extensive à la région sus-pubienne ou périnéale sont les principaux signes retrouvés. Une prise en charge urgente (délai moyen de prise en charge de deux heures avec des extrêmes de 45 minutes et 48 h) en milieu chirurgical avec réparation des corps caverneux et albuginorraphie a été la règle.

Conclusion

La fracture de verge est une urgence urologique relativement peu fréquente dans notre contexte. Son diagnostic reste aisé et est essentiellement clinique. Une prise en charge précoce et correcte en milieu chirurgical est garante d’un bon résultat fonctionnel et esthétique.