bluuebunny/crossref_metadata_2025 huggingface dataset:
Municipal sewage sludge compost promotes Mangifera persiciforma tree growth with no risk of heavy metal contamination of soil
Authors: Chu Shuangshuang , Wu Daoming , Liang Liyin L. , Zhong Fengdi , Hu Yaping , Hu Xinsheng , Lai Can , Zeng Shucai
Published: October 2017

Application of sewage sludge compost (SSC) as a fertilizer on landscaping provides a potential way for the effective disposal of sludge. However, the response of landscape trees to SSC application and the impacts of heavy metals from SSC on soil are poorly understood. We conducted a pot experiment to investigate the effects of SSC addition on Mangifera persiciforma growth and quantified its uptake of heavy metals from SSC by setting five treatments with mass ratios of SSC to lateritic soil as 0%:100% (CK), 15%:85% (S15), 30%:70% (S30), 60%:40% (S60), and 100%:0% (S100). As expected, the fertility and heavy metal concentrations (Cu, Zn, Pb and Cd) in substrate significantly increased with SSC addition. The best performance in terms of plant height, ground diameter, biomass and N, P, K uptake were found in S30, implying a reasonable amount of SSC could benefit the growth of M. persiciforma. The concentrations of Cu, Pb and Cd in S30 were insignificantly different from CK after harvest, indicating that M. persiciforma reduced the risk of heavy metal contamination of soil arising from SSC application. This study suggests that a reasonable rate of SSC addition can enhance M. persiciforma growth without causing the contamination of landscaping soil by heavy metals.
Population genomics of Wolbachia and mtDNA in Drosophila simulans from California
Authors: Signor Sarah
Published: October 2017

Wolbachia pipientis is an intracellular endosymbiont infecting many arthropods and filarial nematodes. Little is known about the short-term evolution of Wolbachia or its interaction with its host. Wolbachia is maternally inherited, resulting in co-inheritance of mitochondrial organelles such as mtDNA. Here I explore the evolution of Wolbachia, and the relationship between Wolbachia and mtDNA, using a large inbred panel of Drosophila simulans. I compare this to the only other large population genomic Wolbachia dataset from D. melanogaster. I find reduced diversity relative to expectation in both Wolbachia and mtDNA, but only mtDNA shows evidence of a recent selective sweep or population bottleneck. I estimate Wolbachia and mtDNA titre in each genotype, and I find considerable variation in both phenotypes, despite low genetic diversity in Wolbachia and mtDNA. A phylogeny of Wolbachia and of mtDNA suggest a recent origin of the infection derived from a single origin. Using Wolbachia and mtDNA titre as a phenotype, I perform the first association analysis using this phenotype with the nuclear genome and find several implicated regions, including one which contains four CAAX-box protein processing genes. CAAX-box protein processing can be an important part of host-pathogen interactions in other systems, suggesting interesting directions for future research.
A new lateral-flow immunochromatographic strip combined with quantum dot nanobeads and gold nanoflowers for rapid detection of tetrodotoxin
Authors: Shen Haicong , Xu Fei , Xiao Meng , Fu Qiangqiang , Cheng Zhenzhu , Zhang Shiwei , Huang Caihong , Tang Yong
Published: October 2017

A sensitive, rapid detection strip based on nanoparticles for tetrodotoxin detection was developed and it meets all testing requirements.
A pyrene-functionalized foldamer: structural impact and recognition properties supported by donor–acceptor interactions
Authors: Aparicio F. , Faour L. , Allain M. , Canevet D. , Sallé M.
Published: October 2017

An electroactive and luminescent foldamer proved to have an original hybridized structure and interacts with electron-poor guests.
Fullerene hexa-adduct scaffolding for the construction of giant molecules
Authors: Nierengarten Jean-François
Published: October 2017

This feature article shows how fullerene hexa-adduct building blocks have been used to prepare giant dendritic systems in a minimum of synthetic steps and summarizes the applications of the resulting nanostructures.
Non-linear sweep voltammetry of adsorbed species: theory and a method to determine formal potentials
Authors: Kätelhön Enno , Compton Richard G.
Published: October 2017

The equilibrium voltammetry of surface-bound analytes is investigated and a new technique to measure formal potentials introduced.
A general method for the inclusion of radiation chemistry in astrochemical models
Authors: Shingledecker Christopher N. , Herbst Eric
Published: October 2017

A general theoretical framework is presented that allows for the addition of cosmic ray-driven radiation chemistry to astrochemical models.
Self-assembling prodrugs
Authors: Cheetham Andrew G. , Chakroun Rami W. , Ma Wang , Cui Honggang
Published: October 2017

Covalent modification of therapeutic compounds is a clinically proven strategy to devise prodrugs with enhanced treatment efficacies. Self-assembly of prodrugs expands the functional space of conventional prodrug design, providing a possible pathway to more effective therapies.
Protonation and electrochemical reduction of rhodium– and iridium–dinitrogen complexes in organic solution
Authors: Connor Gannon P. , Lease Nicholas , Casuras Andrea , Goldman Alan S. , Holland Patrick L. , Mayer James M.
Published: October 2017

In iridium– and rhodium–pincer systems that support both hydrides and dinitrogen complexes, protonation and one-electron reduction lead to dinitrogen loss.
Improving the accuracy of effect-directed analysis: the role of bioavailability
Authors: You Jing , Li Huizhen
Published: October 2017

It is imperative to incorporate bioavailability in effect-directed analysis.
A new route to α,ω-diamines from hydrogenation of dicarboxylic acids and their derivatives in the presence of amines
Authors: Shi Yiping , Kamer Paul C. J. , Cole-Hamilton David J.
Published: October 2017

A new and selective route for the synthesis of polymer precursors, primary diamines or N-substituted diamines, from dicarboxylic acids, diesters, diamides and diols using a Ru/triphos catalyst is reported.
MicroRNA-590-5p regulates cell viability, apoptosis, migration and invasion of renal cell carcinoma cell lines through targeting ARHGAP24
Authors: Wang Lei , Wei Wan-qing , Wu Zi-yu , Wang Gong-cheng
Published: October 2017

Renal cell carcinoma (RCC) is the leading cause of death in renal malignancies.
NARRMDA: negative-aware and rating-based recommendation algorithm for miRNA–disease association prediction
Authors: Peng Lihong , Chen Yeqing , Ma Ning , Chen Xing
Published: October 2017

An increasing amount of evidence indicates that microRNAs (miRNAs) are closely related to many important biological processes and play a significant role in various human diseases.
One-step syntheses of MoS2/graphitic carbon composites with enhanced photocatalytic activity under visible light irradiation
Authors: Bai Hongye , Fan Weiqiang , Ge Yilin , Guan Peng , Shi Weidong
Published: October 2017

MoS2/GC composites were synthesized with sodium alginate as carbon source, and the reason for enhanced photocatalytic activity has been revealed.
Effect of including the carbon nanotube and graphene oxide on the electrocatalytic behavior of the Ni–W alloy for the hydrogen evolution reaction
Authors: Elias Liju , Hegde A. Chitharanjan
Published: October 2017

The present work reports the electrocatalytic activities of the composite coatings of Ni–W developed using the carbon nanotube (CNT) and graphene oxide (GO).
Antibiotics and specialized metabolites from the human microbiota
Authors: Mousa Walaa K. , Athar Bilal , Merwin Nishanth J. , Magarvey Nathan A.
Published: October 2017

Human microbiota associated with each body site produce specialized molecules to kill human pathogens. Advanced bioinformatics tools will help to discover unique microbiome chemistry.
Self-assembly of metal/semiconductor heterostructures via ligand engineering: unravelling the synergistic dual roles of metal nanocrystals toward plasmonic photoredox catalysis
Authors: Jiang Ke-Yi , Weng Ya-Li , Guo Si-Yi , Yu Yan , Xiao Fang-Xing
Published: October 2017

A cooperative synergy arising from the SPR and electron-withdrawal effects of gold nanocrystals was simultaneously and unambiguously unraveled for plasmonic photoredox catalysis.
Effects of oxidation on the plasmonic properties of aluminum nanoclusters
Authors: Douglas-Gallardo Oscar A. , Soldano Germán J. , Mariscal Marcelo M. , Sánchez Cristián Gabriel
Published: October 2017

Using a variety of simulation methods we reveal the effects of oxidation on the surface plasmon resonance of aluminum nanoparticles.
Highly stretchable, sensitive strain sensors with a wide linear sensing region based on compressed anisotropic graphene foam/polymer nanocomposites
Authors: Zeng Zhihui , Seyed Shahabadi Seyed Ismail , Che Boyang , Zhang Youfang , Zhao Chenyang , Lu Xuehong
Published: October 2017

The sensors are fabricated by unidirectional freeze-drying, compression of the resultant graphene foams, and infiltration with polydimethylsiloxane.
A silver nanoislands on silica spheres platform: enriching trace amounts of analytes for ultrasensitive and reproducible SERS detection
Authors: Wang Zhongshun , Feng Lei , Xiao Dongyang , Li Ning , Li Yao , Cao Danfeng , Shi Zuosen , Cui Zhanchen , Lu Nan
Published: October 2017

A substrate for ultrasensitive and reproducible SERS detections is fabricated by depositing silver on a layer of super-hydrophobic silica spheres.
Accessing 2-substituted piperidine iminosugars by organometallic addition/intramolecular reductive amination: aldehyde vs. nitrone route
Authors: Mirabella S. , Fibbi G. , Matassini C. , Faggi C. , Goti A. , Cardona F.
Published: October 2017

A novel dual strategy to build 2-substituted trihydroxypiperidines.
Controlled poly(olefin)s via decarboxylation of poly(acrylic acid)
Authors: Chapman Robert , Melodia Daniele , Qu Jian-Bo , Stenzel Martina H.
Published: October 2017

A simple post-polymerisation modification route to a variety of well-controlled polyolefin homo- and block-copolymers is shown via decarboxylation of poly(acrylic acid) with dialkylzinc reagents.
Bioinspired coating of TiO2nanoparticles with antimicrobial polymers by Cu(0)-LRP: grafting to vs. grafting from
Authors: Guo Shutong , Zhang Qiang , Wang Donghao , Wang Lu , Lin Fang , Wilson Paul , Haddleton David M.
Published: October 2017

Titanium dioxide nanoparticles coated with non-leachable biocides were prepared by Cu(0)-LRP of tertiary-amine-containing monomersvia“grafting to” and “grafting from” strategies.
Luminescent porous organic polymer nanotubes for highly selective sensing of H2S
Authors: Guo Lin , Wang Meng , Zeng Xiaofei , Cao Dapeng
Published: October 2017

In this study, we synthesize a luminescent porous organic polymer nanotube (PNT-1) through copolymerization of the monomers of TBT and 2,6-DP by Ni-catalyzed Yamamoto reaction, and found that PNT-1 can be used as an efficient luminescent probe for sensitively and selectively sensing H2S gas, and it is also applicable for sensing H2S in vitro assay system simulated by using PBS buffer solution.
Visible light photoredox catalyzed semisynthesis of the analogues of maclekarpine E: a series of 6-vinyl substituted dihydrobenzophenanthridine alkaloids
Authors: Qing Zhixing , Cao Hualiang , Cheng Pi , Wang Wei , Zeng Jianguo , Xie Hongqi
Published: October 2017

A photoredox neutral vinylation of dihydrobenzophenanthridines 5 was developed to access the analogue of maclekarpine E (8). In this reaction, Ir(ppy)2(dtbbpy)PF6 was used as a photocatalyst (PC) and α-amino C-radicals 6 were the key reactive intermediates.
Bias-dependent local structure of water molecules at a metallic interface
Authors: Pedroza Luana S. , Brandimarte Pedro , Rocha Alexandre Reily , Fernández-Serra M.-V.
Published: October 2017

We combine Density Functional Theory (DFT) and Non-Equilibrium Green’s Function (NEGF) methods to study the electronic properties and atomic forces of a water molecule at metallic interfaces.
Fusion of structural and textural features for melanoma recognition
Authors: Adjed Faouzi , Safdar Gardezi Syed Jamal , Ababsa Fakhreddine , Faye Ibrahima , Chandra Dass Sarat
Published: October 2017

Melanoma is one the most increasing cancers since past decades. For accurate detection and classification, discriminative features are required to distinguish between benign and malignant cases. In this study, the authors introduce a fusion of structural and textural features from two descriptors. The structural features are extracted from wavelet and curvelet transforms, whereas the textural features are extracted from different variants of local binary pattern operator. The proposed method is implemented on 200 images from dermoscopy database including 160 non‐melanoma and 40 melanoma images, where a rigorous statistical analysis for the database is performed. Using support vector machine (SVM) classifier with random sampling cross‐validation method between the three cases of skin lesions given in the database, the validated results showed a very encouraging performance with a sensitivity of 78.93%, a specificity of 93.25% and an accuracy of 86.07%. The proposed approach outperforms the existing methods on the database.
Compact rectenna based on a fractal geometry with a high conversion energy efficiency per area
Authors: Chuma Euclides Lourenço , Rodríguez Lisandro de la Torre , Iano Yuzo , Roger Leonardo L. Bravo , Sanchez‐Soriano Miguel‐Angel
Published: October 2017

This work presents the design of a rectenna topology by using a compact microstrip patch antenna based on a fractal model and with the rectifier circuit integrated into the same physical structure. This configuration presents a very reduced circuit area, which makes the proposed rectenna circuit suitable for harvesting and wireless power transfer applications where the size is critical. The proposed compact rectenna, implemented on a low‐cost FR‐4 substrate, can harvest RF power from 2.45 GHz (ISM band) with a efficiency of ∼62% when the input power harvested by the rectenna is +2 dBm. The suggested rectenna has been manufactured and experimentally characterised, showing a good agreement with the expected simulated results.
Broadening the beam‐width of microstrip antenna by the induced vertical currents
Authors: Yang Guangwei , Li Jian‐Ying , Wei Dujuan , Zhou Shigang , Yang Jiangjun
Published: October 2017

In this study, a method to broaden the beamwidth of an aperture couple feed microstrip antenna is investigated. Two metal walls are put at the bilateral sides of an original microstrip antenna in the E‐plane (xoz‐plane). The vertical current on the metal walls is induced by E‐field from the horizontal current on the radiating patch of the microstrip antenna. The beamwidth of the antenna is broadened by both the horizontal and vertical currents. A novel wide beamwidth aperture couple feed microstrip antenna (WBMA) is designed according to the proposed method. The simulated and measured reflection coefficients and radiation patterns of the WBMA are presented and compared with the original microstrip antenna. Compared with the original microstrip antenna, the half‐power beamwidth (HPBW) is obviously improved, which the HPBW is 236° in the E‐plane and 124° in the H‐plane at 9.0 GHz. Good radiation characteristics of the new structure antenna have been obtained in the whole operating frequency band.
Low‐noise amplifier by using a signal‐reuse wake‐up technology
Authors: Hsieh Jian‐Yu
Published: October 2017

A V‐band low‐power signal‐reuse low‐noise amplifier (SRLNA) implemented in 90 nm complementary metal–oxide–semiconductor technology is presented. The proposed SRLNA uses zero‐VT and signal‐reuse wake‐up technologies to improve wake‐up sensitivity and reduce power consumption. The SRLNA can be activated or turned off automatically based on the amplitude of the radio‐frequency signal power. Time delays of the zero‐VT envelope detector and limiting amplifier are analysed in order to loose the constraint on the maximum data‐rate. Moreover, the relationship between noise figure (NF), power gain (S21), input and output return losses (S11 and S22) of the SRLNA are discussed in detail, with the quality factors Qnf, QI, Qin, and QL defined for NF, S21, S11, and S22 parameters derivations. The proposed SRLNA consumes 25 and 12 mW at activate and sleep modes, respectively. The sensitivity of the proposed SRLNA can achieve about −50 dBm.
Experimental investigations of ball screws over static and accelerating torque‐based lead factor in CNC machining centre
Authors: Verma Kuldeep , Belokar Rajendra M.
Published: October 2017

This study deals with the rigorous evaluation of computer numeric control (CNC) machining centre for the torque computation. A novel model has been proposed for the CNC feed drive system investigations. Initially, mathematical equations have been derived for the CNC feed drive system explorations. Next, the torque has been calculated over three factors namely: lead, feed force, and accelerating speed. Further, these proposed equations have been implemented over the deployed model. Finally, comprehensive analytical investigations have been made to highlight the relation among static toque with feed force and rated torque with lead values.
Dust reddening and extinction curves toward gamma-ray bursts at z > 4
Authors: Bolmer J. , Greiner J. , Krühler T. , Schady P. , Ledoux C. , Tanvir N. R. , Levan A. J.
Published: October 2017

Context. Dust is known to be produced in the envelopes of asymptotic giant branch (AGB) stars, the expanded shells of supernova (SN) remnants, and in situ grain growth within the interstellar medium (ISM), although the corresponding efficiency of each of these dust formation mechanisms at different redshifts remains a topic of debate. During the first Gyr after the Big Bang, it is widely believed that there was not enough time to form AGB stars in high numbers, hence the dust at this epoch is expected to be purely from SNe or subsequent grain growth in the ISM. The time period corresponding to z ~ 5−6 is thus expected to display the transition from SN-only dust to a mixture of both formation channels as is generally recognized at present.

Aims. Here we aim to use afterglow observations of gamma-ray bursts (GRBs) at redshifts larger than z > 4 to derive host galaxy dust column densities along their line of sight and to test if a SN-type dust extinction curve is required for some of the bursts.

Methods. We performed GRB afterglow observations with the seven-channel Gamma-Ray Optical and Near-infrared Detector (GROND) at the 2.2 m MPI telescope in La Silla, Chile (ESO), and we combined these observations with quasi-simultaneous data gathered with the XRT telescope on board the Swift satellite.

Results. We increase the number of measured AV values for GRBs at z > 4 by a factor of ~2–3 and find that, in contrast to samples at mostly lower redshift, all of the GRB afterglows have a visual extinction of AV < 0.5 mag. Analysis of the GROND detection thresholds and results from a Monte Carlo simulation show that although we partly suffer from an observational bias against highly extinguished sight-lines, GRB host galaxies at 4 < z < 6 seem to contain on average less dust than at z ~ 2. Additionally, we find that all of the GRBs can be modeled with locally measured extinction curves and that the SN-like dust extinction curve, as previously found toward GRB 071025, provides a better fit for only two of the afterglow SEDs. However, because of the lack of highly extinguished sight lines and the limited wavelength coverage we cannot distinguish between the different scenarios. For the first time we also report a photometric redshift of zphot = 7.88-0.94+0.75 for GRB 100905A, making it one of the most distant GRBs known to date.
An updated Type II supernova Hubble diagram
Authors: Gall E. E. E. , Kotak R. , Leibundgut B. , Taubenberger S. , Hillebrandt W. , Kromer M. , Burgett W. S. , Chambers K. , Flewelling H. , Huber M. E. , Kaiser N. , Kudritzki R. P. , Magnier E. A. , Metcalfe N. , Smith K. , Tonry J. L. , Wainscoat R. J. , Waters C.
Published: October 2017

We present photometry and spectroscopy of nine Type II-P/L supernovae (SNe) with redshifts in the 0.045 ≲ z ≲ 0.335 range, with a view to re-examining their utility as distance indicators. Specifically, we apply the expanding photosphere method (EPM) and the standardized candle method (SCM) to each target, and find that both methods yield distances that are in reasonable agreement with each other. The current record-holder for the highest-redshift spectroscopically confirmed supernova (SN) II-P is PS1-13bni (z = 0.335−0.012+0.009), and illustrates the promise of Type II SNe as cosmological tools. We updated existing EPM and SCM Hubble diagrams by adding our sample to those previously published. Within the context of Type II SN distance measuring techniques, we investigated two related questions. First, we explored the possibility of utilising spectral lines other than the traditionally used Fe iiλ5169 to infer the photospheric velocity of SN ejecta. Using local well-observed objects, we derive an epoch-dependent relation between the strong Balmer line and Fe iiλ5169 velocities that is applicable 30 to 40 days post-explosion. Motivated in part by the continuum of key observables such as rise time and decline rates exhibited from II-P to II-L SNe, we assessed the possibility of using Hubble-flow Type II-L SNe as distance indicators. These yield similar distances as the Type II-P SNe. Although these initial results are encouraging, a significantly larger sample of SNe II-L would be required to draw definitive conclusions.
ATCA observations of the MACS-Planck Radio Halo Cluster Project
Authors: Martinez Aviles G. , Johnston-Hollitt M. , Ferrari C. , Venturi T. , Democles J. , Dallacasa D. , Cassano R. , Brunetti G. , Giacintucci S. , Pratt G. W. , Arnaud M. , Aghanim N. , Brown S. , Douspis M. , Hurier J. , Intema H. T. , Langer M. , Macario G. , Pointecouteau E.
Published: October 2017

Aim. A fraction of galaxy clusters host diffuse radio sources whose origins are investigated through multi-wavelength studies of cluster samples. We investigate the presence of diffuse radio emission in a sample of seven galaxy clusters in the largely unexplored intermediate redshift range (0.3 < z < 0.44).

Methods. In search of diffuse emission, deep radio imaging of the clusters are presented from wide band (1.1–3.1 GHz), full resolution (~5 arcsec) observations with the Australia Telescope Compact Array (ATCA). The visibilities were also imaged at lower resolution after point source modelling and subtraction and after a taper was applied to achieve better sensitivity to low surface brightness diffuse radio emission. In case of non-detection of diffuse sources, we set upper limits for the radio power of injected diffuse radio sources in the field of our observations. Furthermore, we discuss the dynamical state of the observed clusters based on an X-ray morphological analysis with XMM-Newton.

Results. We detect a giant radio halo in PSZ2 G284.97-23.69 (z = 0.39) and a possible diffuse source in the nearly relaxed cluster PSZ2 G262.73-40.92 (z = 0.421). Our sample contains three highly disturbed massive clusters without clear traces of diffuse emission at the observed frequencies. We were able to inject modelled radio haloes with low values of total flux density to set upper detection limits; however, with our high-frequency observations we cannot exclude the presence of RH in these systems because of the sensitivity of our observations in combination with the high z of the observed clusters.
The sunflower crop in Argentina: past, present and potential future
Authors: Castaño Fernando D.
Published: October 2017

Sunflower was a crop of great importance in Argentina until 2002; it was ranked among the countries with the largest production, about 18% of the world total. Currently, it is in the fourth place, with only 7%. Several factors caused Argentina to lose its leadership, the most important being that farmers preferred the soybean crop because of its competitiveness pushing sunflower to areas where the former crop was not adapted. However, in 2016/2017 there was an increase in area and production of sunflower, probably associated with the reduction of state intervention in farmer's income because export duties were totally eliminated, while those for soybean remained high. International forecasts suggest that an increase in the demand for sunflower oil and by-products is expected. Argentinean farmers can make a significant contribution to meeting these needs. The whole sunflower chain of value, grouped in the association ASAGIR, makes continuous efforts to improve the sunflower product, by research programs and other activities which will render sunflower more attractive for farmer. It is likely that, in a short time, Argentina could regain its place on the podium of sunflower producing countries.
Versatile Pyrolytic Synthesis of Fused Polycyclic Heteroaromatic Compounds
Authors: Aitken R. , Garnett Alasdair
Published: October 2017

Thirty-six new stabilised phosphonium ylides designed to undergo thermal loss of Ph3PO and radical domino cyclisation have been prepared and are generally found to undergo the desired reaction under flash vacuum pyrolysis conditions at 850 °C. A wide range of ­tetra- and pentacyclic fused-ring heterocycles, many previously unknown, are thus formed in moderate to high yield in a single step. By using suitably substituted starting materials, substituents such as CH3 and Cl can be installed at various positions in the products. The method has also been demonstrated in a combinatorial mode to generate a small library of twelve fused-ring heterocycles in a single pyrolysis.
Pincer Ruthenium Catalyzed Intramolecular Silylation of C(sp2)–H Bonds
Authors: Huang Zheng , Fang Huaquan , He Qiaoxing , Liu Guixia
Published: October 2017

Reported herein is a highly efficient intramolecular silylation of aromatic C–H bonds catalyzed by a pincer ruthenium complex, giving benzoxasiloles under relatively mild reaction conditions with broad substrate scope and low catalyst loadings. The silylation product can be further converted into a biaryl product by Pd-catalyzed Hiyama–­Denmark cross-coupling reactions.
Vein of Galen Aneurysmal Malformation with Transvenous Endovascular Treatment in an Adult: Case Report
Authors: Vale João , Vale Benjamim , Macêdo Lívio , Araújo Marx , Sousa Thiago
Published: October 2017

Vein of Galen aneurysmal malformation (VGAM) is the result of the direct communication between the arterial network and the median prosencephalic vein. It is a rare vascular congenital malformation representing less than 1% of intracranial abnormalities. This finding is very rare in adults, and it may or may not present symptoms during childhood. Most cases of VGAM can be detected in the fetus by ultrasonography. The referral of pregnant women with fetuses with this condition to centers where better facilities and resources for childbirth and immediate postpartum care are available has resulted in considerable improvement in the prognosis of newborns. Regarding treatment, the endovascular approach to VGAM includes arterial embolization and percutaneous transvenous techniques. The transvenous endovascular treatment was chosen in the case presented in this article.
Effect of Maternal Age and Fetal Number on the Risk of Hypertensive Disorders of Pregnancy
Authors: Merriam Audrey , Jung Julley , Gyamfi-Bannerman Cynthia , Smith Devin
Published: October 2017

Objective Our primary objective was to compare the differential contribution of fetal number and maternal age to the risk of hypertensive disorders of pregnancy (HDP).

Study Design This was a secondary analysis of a large study of primary cesarean delivery. Women with singleton, twin, or triplet gestations were included. Women were divided into groups based on fetal number and maternal age. The primary outcome was HDP. A logistic regression model was fit to adjust for confounders. The incidence of HDP was compared with the reference group and within exposure groups.

Results Of the 70,417 women included, HDP occurred in 8,079 (12%) women. The frequency of HDP among the comparison groups ranged from 11 to 38%. Nearly all groups had significantly increased risk of HDP compared with young maternal age singletons. Twin and triplet gestations increased the risk of HDP over singletons irrespective of maternal age after adjusting for baseline disease and race. The risk of HDP did not significantly increase with maternal age when fetal number was similar.

Conclusion Fetal number significantly increased the risk of HDP and contributed more to that risk than maternal age. Maternal age became significant in groups with age greater than 40 years.
The U.S. Twin Delivery Volume and Association with Cesarean Delivery Rates: A Hospital-Level Analysis
Authors: Robinson Julian , Carusi Daniela , Little Sarah , Easter Sarah
Published: October 2017

Objective The objective of this study was to test whether hospitals experienced in twin delivery have lower rates of cesarean delivery for twins.

Methods We divided obstetric hospitals in the 2011 National Inpatient Sample by quartile of annual twin deliveries and compared twin cesarean delivery rates between hospitals with weighted linear regression. We used Pearson's coefficients to correlate a hospital's twin cesarean delivery rate to its overall cesarean delivery and vaginal birth after cesarean (VBAC) rates.

Results Annual twin delivery volume ranged from 1 to 506 across the 547 analyzed hospitals with a median of 10 and mode of 3. Adjusted rates of cesarean delivery were independent of delivery volume with a rate of 75.5 versus 74.8% in the lowest and highest volume hospitals (p = 0.09 across quartiles). A hospital's cesarean delivery rate for twins moderately correlated with the overall cesarean rate (r = 0.52, p < 0.01) and inversely correlated with VBAC rate (r =  − 0.42, p < 0.01).

Conclusion Most U.S. obstetrical units perform a low volume of twin deliveries with no decrease in cesarean delivery rates at higher volume hospitals. Twin cesarean delivery rates correlate with other obstetric parameters such as singleton cesarean delivery and VBAC rates suggesting twin cesarean delivery rate is more closely related to a hospital's general obstetric practice than its twin delivery volume.
Transkranielle elektrische Hirnstimulation
Authors: Reis Janine , Fritsch Brita
Published: October 2017

Die transkranielle elektrische Hirnstimulation durch schwachen Gleichstrom (tDCS) oder Wechselstrom (tACS, tRNS) wird klinisch und experimentell zunehmend eingesetzt, um kognitive und motorische Funktionen bei gesunden Personen und Patienten mit neurologischen Erkrankungen zu verbessern. Diese Übersichtsarbeit fokussiert auf den therapeutischen Stellenwert der Gleichstromstimulation in der Neuro-rehabilitation und bietet eine Übersicht zur Studienlage bei motorischen und nicht-motorischen Symptomen nach Schlaganfall, Aufmerksamkeits- und Bewusstseinsstörungen sowie bei Morbus Parkinson.
Endoskopische Mukosaresektion (EMR) mit nachfolgender Radiofrequenzablation (RFA) bei neoplastischem Barrett-Ösophagus bzw. Barrett-Frühkarzinom ist der alleinigen radikalen endoskopischen Resektion auch ökonomisch überlegen
Authors: Wilke Michael , Rathmayer Markus , Schenker Mike , Schepp Wolfgang
Published: October 2017

Einleitung Neoplastische Veränderungen (gering- bzw. hochgradige intraepitheliale Neoplasie [L- bzw. HGIEN] oder Frühkarzinom) bei Barrett-Ösophagus werden mit unterschiedlichen Verfahren behandelt. In der vorliegenden Untersuchung werden klinisch-ökonomische Aspekte der alleinigen schrittweisen radikalen endoskopische Resektion (SRER) einer Kombinationsbehandlung mit EMR (Endoskopische Mukosaresektion) und RFA (Radiofrequenzablation) gegenübergestellt.

Material und Methoden Es wurden die klinischen Behandlungsdaten einer randomisierten kontrollierten Studie 1 verwendet, um darauf aufbauend ein ökonomisches Modell der Behandlungskosten zu entwickeln, wie sie entsprechend der Vergütung nach dem deutschen Krankenhausentgeltsystem (G-DRG) entstehen. In die Berechnung sind sowohl die initialen Therapiekosten (vergütet über G-DRG) als auch die Kosten zur Behandlung von Folgekomplikationen eingeflossen.

Ergebnisse Medizinisch wie ökonomisch weist die Behandlung mittels EMR + RFA Vorteile gegenüber der SRER auf 1. Die erfolgreiche vollständige Resektion bzw. Destruktion von neoplastischem intestinal metaplastischen Gewebe ist bei beiden Verfahren vergleichbar. Behandlungswürdige Akut- (24 % bei SRER vs. 13 % EMR + RFA) und Spätkomplikationen (88 % bei SRER vs. 13 % EMR + RFA) sind bei der SRER deutlich häufiger als bei der EMR + RFA.

Diskussion Während SRER als alleinige Therapie zunächst kostengünstiger erscheint, verschieben die ungleich höheren Komplikationsraten mit Folgeeingriffen das Kostenniveau deutlich über das von EMR + RFA. Insgesamt belaufen sich die Behandlungskosten in der SRER Gruppe auf € 13 272,11 und in der EMR + RFA Gruppe auf € 11 389,33. Die EMR + RFA-Gruppe erzielt somit einen Kostenvorteil von € 1882,78. Die vorliegende Studie zeigt, dass eine Kombinationstherapie des neoplastischen Barrett Ösophagus mittels EMR + RFA auch in ökonomischer Hinsicht sinnvoll erscheint.
Kurative endoskopische Therapie: Welche Läsionen eignen sich?
Authors: Munding Johanna , Tannapfel Andrea
Published: October 2017

Dank flächendeckender Vorsorgeuntersuchungen werden immer mehr Tumore im Gastrointestinaltrakt so früh diagnostiziert, dass sie endoskopisch resezierbar sind. Doch nicht alle Läsionen eignen sich für eine kurative endoskopische Therapie. Abhängig ist dies vom lymphogenen Metastasierungsrisiko, das sich anhand histopathologischer Charakteristika abschätzen lässt.
Aktuelle Forschungsaktivitäten zur personenzentrierten Medizin in akademischen Instituten für Allgemeinmedizin in Deutschland und Österreich
Authors: Weber Annemarie , Schelling Jörg , Kohls Niko , van Dyck Marcus , Poggenburg Stephanie , Vajda Christian , Hirsch Jameson , Sirois Fuschia , Toussaint Loren , Offenbächer Martin
Published: October 2017

Ziel der Studie Die personenzentrierte Medizin (PZM) mit Fokus auf einer humanistisch-biografisch orientierten Medizin und einem erweiterten, positiv-salutogenen Gesundheitsbegriff ist ein zentraler Bestandteil der Arzt-Patienten Beziehung in der Allgemeinmedizin. Ziel dieser Analyse ist es deshalb, Prävalenz und Typ von Forschungsprojekten in universitären Instituten für Allgemeinmedizin in Deutschland (D) und Österreich (Ö) sowie deren thematische Schwerpunkte in den Bereichen PZM, Gesundheitsförderung (GF), Prävention (PRÄ) und konventioneller Medizin (KM) zu erfassen.

Methodik Es wurde eine Recherche auf den Webseiten von 30 Instituten für Allgemeinmedizin mit dem Fokus auf deren Forschungsprojekten im Zeitraum September–Dezember 2015 durchgeführt. Die erfassten Projekte wurden in die 5 Kategorien PZM, GF, PRÄ, KM und sonstige Themen eingeteilt. Anschließend erfolgte eine Identifikation der Zielgruppen und thematischen Schwerpunkte in den ersten 4 Kategorien, vertieft in den Bereichen PZM und GF.

Ergebnisse Die Suche ergab insgesamt 541 Forschungsprojekte (FP), 452 in Deutschland und 89 in Österreich. Es wurden nur FP erfasst, die ausdrücklich als solche gekennzeichnet waren. 70 FP untersuchten Aspekte der PZM, 15 FP Aspekte der GF, 32 FP Aspekte der PRÄ und 395 FP Aspekte der konventionellen Medizin. Chronisch kranke Patienten stellten in den beiden Kategorien PZM (24 von 70) und GF (7 von 15) die häufigste Zielgruppe dar. Häufigster thematischer Schwerpunkt der PZM-Projekte war das Thema Kommunikation (13 von 70), bei den GF-Projekten die körperliche Aktivität (6 von 15).

Schlussfolgerung Die Mehrzahl der Forschungsprojekte beschäftigt sich mit konventionellen medizinischen Themen. Mit einem Anteil von 13% (PZM) bzw. 16% (PZM & GF) liegt die Forschungsaktivität im Bereich PZM bzw. GF in D und Ö unter dem europäischen Durchschnitt von 20%. Um diese Themenbereiche verstärkt in die hausärztliche Versorgung zu integrieren ist es aus unserer Sicht notwendig u. a. die Forschung zu Voraussetzungen und Barrieren von PZM und GF im ärztlichen Alltag in Deutschland und Österreich zu vertiefen.
Akute Doppelbilder: Differenzialdiagnose, Abklärung und Behandlungsoptionen
Authors: Kelbsch Carina , Besch Dorothea , Wilhelm Helmut
Published: October 2017

Akute Doppelbilder können von harmlosen Störungen des optischen Systems bis hin zu gefährlichen intrakraniellen oder intraorbitalen Prozessen mit entsprechenden Bewegungseinschränkungen der Augen verschiedenste Ursachen haben. Entsprechend schwierig kann die Entscheidung bezüglich der Erfordernisse weiterer diagnostischer Abklärungen erscheinen. Dieser Beitrag soll eine kurze, strukturierte Übersicht über die häufigsten Differenzialdiagnosen akuter Doppelbilder liefern und deren Abklärung sowie Behandlungsoptionen aufzeigen.
Positive and negative gain exceeding unity magnitude in silicon quantum well metal-oxide-semiconductor transistors
Authors: Hu Gangyi , Wijesinghe Udumbara , Naquin Clint , Maggio Ken , Edwards H. L. , Lee Mark
Published: October 2017

Intrinsic gain (AV) measurements on Si quantum well (QW) n-channel metal-oxide-semiconductor (NMOS) transistors show that these devices can have |AV| > 1 in quantum transport negative transconductance (NTC) operation at room temperature. QW NMOS devices were fabricated using an industrial 45 nm technology node process incorporating ion implanted potential barriers to define a lateral QW in the conduction channel under the gate. While NTC at room temperature arising from transport through gate-controlled QW bound states has been previously established, it was unknown whether the quantum NTC mechanism could support gain magnitude exceeding unity. Bias conditions were found giving both positive and negative AV with |AV| > 1 at room temperature. This result means that QW NMOS devices could be useful in amplifier and oscillator applications.
On self-sustainment of DC discharges with gridded anode
Authors: Yuan Chengxun , Yao Jingfeng , Eliseev S. I. , Bogdanov E. A. , Kudryavtsev A. A. , Zhou Zhongxiang
Published: October 2017

The paper presents results of numerical investigation of a large-volume plasma source based on a DC discharge with gridded anode. Geometry and configuration of the electrodes were chosen so as to ensure the formation of a cathode sheath, which would accelerate electrons up to high energies and inject them into the post-anode space and create plasma. Simulations were carried out using a hybrid model, and distributions of the main discharge parameters were obtained in a wide range of currents. At low currents, cathode sheath occupies whole interelectrode gap while plasma is formed in the post-anode space. It is shown that ions moving through the anode grid into the interelectrode gap cause reduction of discharge voltage when compared to the case of classical obstructed discharge with virtually closed anode grid. At higher currents, however, plasma is formed within the interlectrode gap as well, and ions moving from plasma in the post-anode space become trapped by reversed electric field. This essentially nullifies influence of the post-anode plasma on discharge properties.
Activity coefficients from molecular simulations using the OPAS method
Authors: Kohns Maximilian , Horsch Martin , Hasse Hans
Published: October 2017

A method for determining activity coefficients by molecular dynamics simulations is presented. It is an extension of the OPAS (osmotic pressure for the activity of the solvent) method in previous work for studying the solvent activity in electrolyte solutions. That method is extended here to study activities of all components in mixtures of molecular species. As an example, activity coefficients in liquid mixtures of water and methanol are calculated for 298.15 K and 323.15 K at 1 bar using molecular models from the literature. These dense and strongly interacting mixtures pose a significant challenge to existing methods for determining activity coefficients by molecular simulation. It is shown that the new method yields accurate results for the activity coefficients which are in agreement with results obtained with a thermodynamic integration technique. As the partial molar volumes are needed in the proposed method, the molar excess volume of the system water + methanol is also investigated.
Development of a novel once-through flow visualization technique for kinetic study of bulk and surface scaling
Authors: Sanni O. , Bukuaghangin O. , Huggan M. , Kapur N. , Charpentier T. , Neville A.
Published: October 2017

There is a considerable interest to investigate surface crystallization in order to have a full mechanistic understanding of how layers of sparingly soluble salts (scale) build on component surfaces. Despite much recent attention, a suitable methodology to improve on the understanding of the precipitation/deposition systems to enable the construction of an accurate surface deposition kinetic model is still needed. In this work, an experimental flow rig and associated methodology to study mineral scale deposition is developed. The once-through flow rig allows us to follow mineral scale precipitation and surface deposition in situ and in real time. The rig enables us to assess the effects of various parameters such as brine chemistry and scaling indices, temperature, flow rates, and scale inhibitor concentrations on scaling kinetics. Calcium carbonate (CaCO3) scaling at different values of the saturation ratio (SR) is evaluated using image analysis procedures that enable the assessment of surface coverage, nucleation, and growth of the particles with time. The result for turbidity values measured in the flow cell is zero for all the SR considered. The residence time from the mixing point to the sample is shorter than the induction time for bulk precipitation; therefore, there are no crystals in the bulk solution as the flow passes through the sample. The study shows that surface scaling is not always a result of pre-precipitated crystals in the bulk solution. The technique enables both precipitation and surface deposition of scale to be decoupled and for the surface deposition process to be studied in real time and assessed under constant condition.
Effective Floquet Hamiltonian theory of multiple-quantum NMR in anisotropic solids involving quadrupolar spins: Challenges and Perspectives
Authors: Ganapathy Vinay , Ramachandran Ramesh
Published: October 2017

The response of a quadrupolar nucleus (nuclear spin with I >12) to an oscillating radio-frequency pulse/field is delicately dependent on the ratio of the quadrupolar coupling constant to the amplitude of the pulse in addition to its duration and oscillating frequency. Consequently, analytic description of the excitation process in the density operator formalism has remained less transparent within existing theoretical frameworks. As an alternative, the utility of the “concept of effective Floquet Hamiltonians” is explored in the present study to explicate the nuances of the excitation process in multilevel systems. Employing spin I =32 as a case study, a unified theoretical framework for describing the excitation of multiple-quantum transitions in static isotropic and anisotropic solids is proposed within the framework of perturbation theory. The challenges resulting from the anisotropic nature of the quadrupolar interactions are addressed within the effective Hamiltonian framework. The possible role of the various interaction frames on the convergence of the perturbation corrections is discussed along with a proposal for a “hybrid method” for describing the excitation process in anisotropic solids. Employing suitable model systems, the validity of the proposed hybrid method is substantiated through a rigorous comparison between simulations emerging from exact numerical and analytic methods.
Experimental approach for measuring cylindrical flexoelectric coefficients
Authors: Zhang Shuwen , Liu Kaiyuan , Wu Tonghui , Xu Minglong , Shen Shengping
Published: October 2017

Flexoelectricity is a property of dielectric materials by which applied strain gradients induce electric polarizations within dielectric materials. Experimental research into the tensor components of the flexoelectric coefficient is essential. In this work, an experimental approach for measurement of the flexoelectric coefficient tensor components in cylindrical coordinates is developed. Two different experimental methods are designed to obtain the two related unknown flexoelectric coefficient tensor components. Theoretical and finite element analyses are developed and simplified for each experiment, and the related designs are then tested to obtain the coupled electric polarization charges. The two unknown flexoelectric coefficient tensor components of polyvinylidene fluoride are then decoupled. This work provides an experimental method that can be used to obtain multiple unknown flexoelectric coefficient tensor components in solid dielectric materials.
Exciton valley dynamics in monolayer Mo1-xWxSe2 (x = 0, 0.5, 1)
Authors: Ye Jialiang , Niu Binghui , Li Ying , Li Ting , Zhang Xinhui
Published: October 2017

We study the exciton valley dynamics in monolayers MoSe2, Mo0.5W0.5Se2, and WSe2 by employing helicity-resolved two-color transient reflection spectroscopy. The valley depolarization dynamics as a function of the excitation laser energy is studied systematically at above-resonant excitation of excitons at 10 K. A longer intervalley scattering time is obtained as the excitation energy approaches the A exciton resonance for the three studied materials. The excitation energy dependence of exciton valley relaxation proves that the long-range electron-hole exchange interaction dominates the intervalley scattering in transition metal dichalcogenide monolayers. The longer valley scattering time and higher valley polarization degree commonly observed for WSe2 than for MoSe2 is discussed to result from the interplay between the intervalley electron-hole exchange interaction and dark-bright exciton scattering, where the existence of energetically lower lying dark excitonic states in monolayer WSe2 favors the suppression of the intervalley electron-hole exchange interaction.
Performance testing of a carbon fiber array cathode in a hard-tube MILO
Authors: Li An-Kun , Fan Yu-Wei , Qian Bao-Liang
Published: October 2017

In this paper, a carbon fiber array cathode was constructed and the application in a hard-tube magnetically insulated transmission line oscillator (MILO) was investigated. The performance was compared with a traditionally used polymer velvet cathode in the same conditions, where applied electric power ranged from 9 GW to 28 GW and microwave with power level of several GW was the output. The MILO worked on single shot mode or repetitive mode at 5 Hz. For both cathodes, the central frequencies of output microwaves are in the L-band, and the pulse durations (full width at half maximum) range from 25 to 50 ns. Experimental results show that the pulse duration of output microwave of the carbon fiber array cathode is shorter than the velvet cathode, and the power conversion efficiency is also somewhat lower than the velvet cathode. Although the performance testing results show that this carbon fiber array cathode is somewhat not as good as the traditional velvet cathode in the present state, the reasons for the disadvantages of the carbon fiber array cathode have been analyzed and the corresponding solutions are presented to improve the performance of this cathode. If expected solutions are put into effect, this carbon fiber array cathode may be able to replace the velvet cathode.