bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of istradefylline for Parkinson’s disease: A meta-analysis
Authors: Sako Wataru , Murakami Nagahisa , Motohama Keisuke , Izumi Yuishin , Kaji Ryuji
Published: December 2017

Adenosine A2A receptor antagonists are an alternative treatment strategy for Parkinson’s disease. Several randomized placebo controlled studies have tested the effect of A2A receptor antagonist istradefylline, and more robust evidence has been acquired. This meta-analysis aimed to provide evidence for its efficacy and safety on patients with Parkinson’s disease. After a systematic literature search, we calculated the pooled standardized mean difference and risk ratio for continuous and dichotomous variables, respectively. Further, sensitivity analyses were performed to confirm the effect estimated by meta-analyses. Publication bias was assessed by funnel plot and deviation of intercept. Six studies satisfied our inclusion criteria. Istradefylline (40 mg/day) decreased off time and improved motor symptoms of Parkinson’s disease in homogeneous studies. Istradefylline at 20 mg/day decreased off time and improved motor symptoms, but heterogeneity was found in the analysis of the former among studies. There was a significant effect of istradefylline on dyskinesia in homogeneous studies. Publication bias, however, was observed in the comparison of dyskinesia. Other adverse events showed no significant difference. The present meta-analysis suggests that istradefylline at 40 mg/day could alleviate off time and motor symptoms derived from Parkinson’s disease. Dyskinesia might be worsened, but publication bias prevents this from being clear.
Curved surface effect and manipulation of electronic states in nanosilicon
Authors: Huang Zhong-Mei , Huang Wei-Qi , Wu Xue-Ke , Liu Shi-Rong , Qin Cao-Jian
Published: December 2017

It is interesting in low-dimensional nanostructures of silicon that the two quantum effects play different roles in nanosilicon emission, in which the quantum confinement (QC) effect opens band gap and makes emission shift into shorter wavelengths (blue-shift) as the size of the nanocrystals is reduced; however the breaking symmetry originating from impurities on nanosilicon produces the localized electronic states in band gap and makes emission shift into longer wavelengths (red-shift). The results of experiment and calculation demonstrated that the energy levels of nanosilicon can be manipulated through these quantum effects, where the curved surface (CS) effect of impurity atoms bonding on nanosilicon is important in breaking symmetry of nanosilicon system. Here, the CS effect plays an important role on impuritied nanosilicon in smaller scale with larger surface curvature, in which a few characteristic parameters have been found to describe the breaking symmetry of nanosilicon system, such as bonding angle and projecting length of bonds on curved surface. More interesting, the coupling ways between the QC effect and the CS effect determinate the levels position of localized states in band gap and manipulate emission wavelength, where a few new phenomena were explored.
Formic acid: an accelerator and quality promoter for nonseeded growth of CH3NH3PbI3 single crystals
Authors: Lv Qianrui , Lian Zhipeng , Li Qiang , Sun Jia-Lin , Yan Qingfeng
Published: December 2017

With the aid of formic acid, CH3NH3PbI3 single crystals of 9 mm length were directly harvested within 3 days via a nonseeded solution temperature-lowering (STL) method.
Bimetallic–graphene sandwiched core–satellite colloidal nanodendrites as an efficient visible-NIR-sun light active photo-system for carbon dioxide reduction
Authors: Kumar Dinesh , Lee Sang Bong , Park Chan Hee , Kim Cheol Sang
Published: December 2017

The synthesis of multimetallic core–satellite nanodendrites (Pt@Au@rGO) is reported. These were then used as a highly active catalyst for CO2 photoreduction to HCOOH with excellent reusability and colloidal stability.
Controllable synthesis of hierarchical nickel hydroxide nanotubes for high performance supercapacitors
Authors: Wang Yanbing , Shang Bin , Lin Feng , Chen Yu , Ma Ruguang , Peng Bo , Deng Ziwei
Published: December 2017

Hierarchical Ni(OH)2 nanotubes synthesized by a self-sacrificial template method exhibit superior capacitance and stability as electrode materials for supercapacitors.
Direct access to α-sulfenylated amides/esters via sequential oxidative sulfenylation and C–C bond cleavage of 3-oxobutyric amides/esters
Authors: Jiang Yi , Deng Jie-dan , Wang Hui-hong , Zou Jiao-xia , Wang Yong-qiang , Chen Jin-hong , Zhu Long-qing , Zhang Hong-hua , Peng Xue , Wang Zhen
Published: December 2017

An efficient, environmentally benign and unprecedented synthesis of various α-sulfenylated amides/esters has been developed under oxygen atmosphere.
Modelling excitation energy transfer in covalently linked molecular dyads containing a BODIPY unit and a macrocycle
Authors: Azarias Cloé , Cupellini Lorenzo , Belhboub Anouar , Mennucci Benedetta , Jacquemin Denis
Published: December 2017

We model the singlet–singlet Excitation Energy Transfer (EET) process in a panel of large BODIPY–macrocycle dyads, including some azacalixphyrin derivatives.
Electrochemical behavior of Bi4B2O9towards lithium-reversible conversion reactions without nanosizing
Authors: Strauss Florian , Rousse Gwenaëlle , Batuk Dmitry , Tang Mingxue , Salager Elodie , Dražić Goran , Dominko Robert , Tarascon Jean-Marie
Published: December 2017

Galvanostatic charge–discharge curves for a Bi4B2O9/C macrocomposite, highlighting the small voltage hysteresis for the conversion reaction around 300 mV.
Chemical methods for mapping cysteine oxidation
Authors: Alcock Lisa J. , Perkins Michael V. , Chalker Justin M.
Published: December 2017

Methods to characterise oxidative modifications of cysteine help clarify their role in protein function in both healthy and diseased cells.
Functional metal complexes from CuAAC “click” bidentate and tridentate pyridyl-1,2,3-triazole ligands
Authors: van Hilst Quinn V. C. , Lagesse Natalie R. , Preston Dan , Crowley James D.
Published: December 2017

This Frontiers article examines the use of “click” complexes for the development of catalysts, anti-cancer and anti-bacterial agents and emissive materials.
Atomic spectrometry update – a review of advances in environmental analysis
Authors: Butler Owen T. , Cairns Warren R. L. , Cook Jennifer M. , Davidson Christine M. , Mertz-Kraus Regina
Published: December 2017

This review covers advances in the analysis of air, water, plants, soils and geological materials by a range of atomic spectrometric techniques including atomic emission, absorption, fluorescence and mass spectrometry.
Size dependent surface reconstruction in detonation nanodiamonds
Authors: Chang Shery L. Y. , Dwyer Christian , Ōsawa Eiji , Barnard Amanda S.
Published: December 2017

Sub 3 nm diamond particles show size- and shape-dependent surface reconstructions, which have significant impact to their functionality and performance.
Investigation of the retention characteristics of a 26-membered aromatic-aliphatic azamacrocycle bonded silica gel stationary phase for high performance liquid chromatography
Authors: Zhao Wenjie , Liu Longhui , Jia Yunzhen , Yuan Hang , Pan Lining , He Lijun , Xiang Guoqiang , Jiang Xiuming , Zhang Shusheng
Published: December 2017

A 26-membered aromatic-aliphatic azamacrocycle bonded silica gel stationary phase for high performance liquid chromatography was prepared and characterized.
Nanocuboidal-shaped zirconium based metal organic framework for the enhanced adsorptive removal of nonsteroidal anti-inflammatory drug, ketorolac tromethamine, from aqueous phase
Authors: Singh Sukhjinder , Sharma Shelja , Umar Ahmad , Jha Menaka , Mehta Surinder Kumar , Kansal Sushil Kumar
Published: December 2017

Nanocuboidal-shaped zirconium based metal organic framework (UiO-66) was synthesized and used for enhanced adsorptive removal (729.92 mg g−1) of ketorolac tromethamine drug.
Amidoxime-modified chitosan for pigment red 224 enrichment through reversible assembly
Authors: Gou Shaohua , Zhou Yanting , Duan Ming , Peng Chuan , Yang Xiaoyan , Wang Jin
Published: December 2017

An amidoxime-modified chitosan, featuring favorable porosity and super-lipophilic properties, was successfully prepared for pigment red 224 enrichment.
Anticarcinogenic and metal chelation properties of novel hydroxybenzylidene-1-indanone derivatives in the U-251 glioblastoma cell line
Authors: Lozano-Gonzalez Mariana , Ramírez-Apan María Teresa , Nieto-Camacho Antonio , Toscano Ruben Alfredo , Sanchez-Sandoval Ana Laura , Alvarez-Toledano Cecilio
Published: December 2017

A novel series of (Z)-2-(hydroxy(aryl)methylene)-2,3-dihydro-1H-indanone derivatives were designed, synthesized and evaluated as cytotoxic agents against six cancer cell lines.
Structural investigations of (Mn, Dy) co-doped ZnO nanocrystals using X-ray absorption studies
Authors: Tiwari N. , Kumar S. , Ghosh A. K. , Chatterjee S. , Jha S. N. , Bhattacharyya D.
Published: December 2017

EXAFS measurements on sol gel derived (Mn, Dy) co-doped ZnO nanocrystals show that oxygen vacancies are created near the Dy sites into ZnO lattice. Thus, oxygen vacancy assisted bound magnetic polarons contribute to the RTFM in the Dy doped samples.
Asymmetric synthesis of 2,3-disubstituted indolinesviaan organocatalytic intramolecular Michael addition
Authors: Lee Jusung , Ko Kwang Min , Kim Sung-Gon
Published: December 2017

An asymmetric synthesis of 2,3-disubstituted indolines has been developedviaan organocatalytic intramolecular Michael addition.
Influence of external electric field on the electronic structure and optical properties of pyrite
Authors: Li Yuqiong , Chen Jianhua , Zhao Cuihua
Published: December 2017

Optical properties change with the application of electric field on the pyrite crystal.
Zwitterionic polymers showing upper critical solution temperature behavior as draw solutes for forward osmosis
Authors: Ju Changha , Kang Hyo
Published: December 2017

We investigated the suitability of homopolymer with UCST characteristics as draw solutes for the FO process for the first time.
Molecular modeling studies of quinazolinone derivatives as novel PI3Kδ selective inhibitors
Authors: Peng Xiu Xiu , Feng Kai Rui , Ren Yu Jie
Published: December 2017

The main molecular modeling method, the docking results of newly designed compoundD04and the best pharmacophore model are reported herein.
Electrostatic attraction driven and shuttle-like morphology assisted enhancement for tumor uptake
Authors: Lin Min , Liu Shuwei , Wang Dandan , Li Shuyao , Zhang Xue , Ge Rui , Li Xing , Liu Yi , Song Wenzhi , Sun Hongchen , Zhang Hao , Yang Bai
Published: December 2017

Electrostatic attraction can actively enhance the retention of nanomaterials in tumor tissues and shuttle-like morphology also favors tumor uptake.
Metal free and efficient photoelectrocatalytic removal of organic contaminants over g-C3N4nanosheet films decorated with carbon quantum dots
Authors: Zhang Zisheng , Lin Shuanglong , Li Xingang , Li Hong , Cui Wenquan
Published: December 2017

As a typical metal-free semiconductor photocatalyst, a composite photocatalyst comprised of g-C3N4nanosheets decorated with carbon quantum dots (CQDs/g-C3N4) was synthesizedviaa simple ultrasonic dispersion self-assembly method.
VUV photoionization aerosol mass spectrometric study on the iodine oxide particles formed from O3-initiated photooxidation of diiodomethane (CH2I2)
Authors: Wei Nana , Hu Changjin , Zhou Shanshan , Ma Qiao , Mikuška Pavel , Večeřa Zbyněk , Gai Yanbo , Lin Xiaoxiao , Gu Xuejun , Zhao Weixiong , Fang Bo , Zhang Weijun , Chen Jun , Liu Fuyi , Shan Xiaobin , Sheng Liusi
Published: December 2017

IOPs formed from O3-initiated photooxidation of CH2I2 were investigated based on the combination of a thermal desorption/tunable vacuum ultraviolet time-of-flight photoionization aerosol mass spectrometer with a flow reactor for the first time.
Theoretical study on the photophysical properties of boron-fused double helicenes
Authors: Si Yanling , Cheng Yan , Qu Nan , Zhao Xinyu , Yang Guochun
Published: December 2017

Seven boron-fused double helicenes containing different electron-donors or acceptors and their combinations were investigated to shed light on the effective way to enhance the second-order NLO response.
Simultaneous removal of PM and NOx over highly efficient 3DOM W/Ce0.8Zr0.2O2 catalysts
Authors: Cheng Ying , Song Weiyu , Liu Jian , Zhao Zhen , Wei Yuechang
Published: December 2017

Herein, three-dimensional ordered macropore (3DOM) x% W/Ce0.8Zr0.2O2 (x = 0.5, 0.8, 1, 3) catalysts were prepared and employed for the simultaneous removal of PM (particulate matter) and NOx from diesel engine exhaust.
Manipulating resistive states in oxide based resistive memories through defective layers design
Authors: Xu Zhemi , Guan Peiyuan , Younis Adnan , Chu Dewei , Li Sean
Published: December 2017

In this work, multilevel switching was achieved by a strategically designed alternative multi-layer structure with pure and Mn-doped SnO2.
Surface modification of carbon cloth anodes for microbial fuel cells using atmospheric-pressure plasma jet processed reduced graphene oxides
Authors: Chang Shih-Hang , Huang Bo-Yen , Wan Ting-Hao , Chen Jian-Zhang , Chen Bor-Yann
Published: December 2017

Surface modification of a carbon cloth anode by screen-printing rGO and APPJ is promising for manufacturing large-scale MFC stacks.
Fabrication of aqueous-based dual drug loaded silk fibroin electrospun nanofibers embedded with curcumin-loaded RSF nanospheres for drugs controlled release
Authors: Li Huijun , Zhu Jingxin , Chen Song , Jia Lan , Ma Yanlong
Published: December 2017

This paper presents a new nanofabrication method for dual drug loaded regenerated silk fibroin (RSF) nanofibers, based on a simple, colloid-electrospinning technique.
Core–shell structured Ag@C nanocables for flexible ferroelectric polymer nanodielectric materials with low percolation threshold and excellent dielectric properties
Authors: Chen Zhihui , Li Hengfeng , Xie Guangyou , Yang Ke
Published: December 2017

Flexible Ag@C-NC/PVDF nanocomposite materials with low percolation threshold and dielectric constant of 295 at 1 kHz.
A modular approach for multifunctional polymersomes with controlled adhesive properties
Authors: Petit Julien , Thomi Laura , Schultze Jennifer , Makowski Marcin , Negwer Inka , Koynov Kaloian , Herminghaus Stephan , Wurm Frederik R. , Bäumchen Oliver , Landfester Katharina
Published: December 2017

Specific adhesion measurement, realized by micropipette force spectroscopy, of multifunctional polymersomes produced in a microfluidic environment.
Polybenzimidazole membranes with nanophase-separated structure induced by non-ionic hydrophilic side chains for vanadium flow batteries
Authors: Peng Sangshan , Wu Xuemei , Yan Xiaoming , Gao Li , Zhu Yangzhi , Zhang Daishuang , Li Jie , Wang Qian , He Gaohong
Published: December 2017

A nanophase-separated structure is induced in PBI membranes by grafting non-ionic hydrophilic side-chains and ultrahigh proton conductivity is obtained for VFBs.
Self-assembly of polyoxometalate/reduced graphene oxide composites induced by ionic liquids as a high-rate cathode for batteries: “killing two birds with one stone”
Authors: Shen Feng-Cui , Wang Yi-Rong , Li Shun-Li , Liu Jiang , Dong Long-Zhang , Wei Tao , Cui Yu-Cheng , Wu Xing Long , Xu Yan , Lan Ya-Qian
Published: December 2017

High efficiency electrodes for lithium and sodium ion battery have been successfully achieved by the cooperating of crystalline composite Mn3V19-HIL and RGO.
Effects of meso-M(PPh3)2Cl (M = Pd, Ni) substituents on the linear and third-order nonlinear optical properties of chalcogenopyrylium-terminated heptamethines in solution and solid states
Authors: Davydenko Iryna , Benis Sepehr , Shiring Stephen B. , Simon Janos , Sharma Rajesh , Allen Taylor G. , Chi San-Hui , Zhang Qing , Getmanenko Yulia A. , Parker Timothy C. , Perry Joseph W. , Brédas Jean-Luc , Hagan David J. , Van Stryland Eric W. , Barlow Stephen , Marder Seth R.
Published: December 2017

Pd(PPh3)2Cl groups hinder aggregation and afford promising solid-state NLO properties.
An effective strategy to enhance the dielectric constant of organic semiconductors – CPDTTPD-based low bandgap polymers bearing oligo(ethylene glycol) side chains
Authors: Brebels Jeroen , Douvogianni Evgenia , Devisscher Dries , Thiruvallur Eachambadi Raghavendran , Manca Jean , Lutsen Laurence , Vanderzande Dirk , Hummelen Jan C. , Maes Wouter
Published: December 2017

Gradually increasing dielectric constants (up to 6.3) are obtained for a series of PCPDTTPD polymers.
The Use of Magnetic Resonance Imaging (MRI) for the Study of the Velopharynx
Authors: Mason Kazlin , Perry Jamie
Published: December 2017

Magnetic resonance imaging (MRI) has contributed significantly to our understanding of the velopharyngeal mechanism and is the only imaging modality that allows for visualization of the internal musculature in vivo. Although velopharyngeal dysfunction often can be perceived through indirect assessments such as perceptual ratings, acoustic analysis, and pressure-flow assessment, these indirect methods can fail to identify the underlying cause of hypernasality or velopharyngeal dysfunction due to the inability to visualize the primary muscles responsible for speech. Direct imaging methods, such as nasendoscopy or videofluoroscopy, present drawbacks and are limited in the information that is provided within the oral and nasal cavities, as well as the posterior pharynx. MRI studies have enhanced our knowledge of the velopharyngeal system and offer a foundation to establish the utility of using MRI clinically to improve speech outcomes for children with cleft palate and craniofacial anomalies. The purpose of this paper is to provide an overview of the underlying principles of MRI, describe the advantages and disadvantages of MRI, and discusses a standard protocol for assessing velopharyngeal anatomy.
Rethinking Referral Criteria for Adult Cochlear Implant Evaluation
Authors: Bibee Jacqueline M. , Gende Deanna M. , Shohet Jack A.
Published: December 2017

Patients are under-referred for cochlear implant (CI) evaluation in the United States. Recent developments in electric-acoustic combination systems, bimodal solutions, cosmetics/wearability, surgical improvements, and reduced financial barriers are driving expanded CI candidacy. This article summarizes current research on these topics so that hearing professionals may recognize potential CI candidates and confidently refer them for assessment.
Bennet's doubler working as a power booster for triboelectric nano‐generators
Authors: Ghaffarinejad A. , Lu Y. , Hinchet R. , Galayko D. , Hasani J.Y. , Kim S.W. , Basset P.
Published: December 2017

In this Letter, the authors introduce for the first time how a Bennet's doubler conditioning circuit will boost the extracted energy from an electrostatic kinetic energy harvester based on triboelectricity. With zero initial bias on all capacitors, after 1000 charging cycles, the harvested power is amplified by more than 2 orders of magnitude by the Bennet's doubler in comparison to a half‐wave diode bridge. The harvested energy derived from a 3 × 3 cm2 device made of polymer PFA and aluminium is at least 4.6 μJ per tap with the Bennet's doubler conditioning circuit, and only 30 nJ per tap with the half‐wave bridge.
Analytic signal model for flip‐flop based phase‐frequency detectors
Authors: Winterstein A. , Nossek J.A.
Published: December 2017

Flip‐flop based phase‐frequency detectors are widely used in phase‐locked loop circuits. These devices are usually assumed to behave linearly although they consist of non‐linear parts. In this work, a flip‐flop based phase‐frequency detector circuit is analysed. Analytic output signal models are derived for arbitrary input signal frequencies and phases. Exact and approximate closed‐form solutions are found for different frequency ratios. The model is validated by numerical time‐domain simulations.
Event‐triggered adaptive control for a class of non‐linear systems with multiple unknown control directions
Authors: Sun Xifang , Chen Weisheng , Dai Hao
Published: December 2017

This study investigates the event‐triggered adaptive switching stabilisation problem for a class of lower‐triangular non‐linear systems with multiple unknown control directions. A novel Lyapunov‐based event‐triggered adaptive switching control rule is proposed to implement the stability of the closed‐loop system. Moreover, a unified time sequence is introduced by combining two time sequences which are generated from such a control rule. The designed event‐triggered adaptive switching controller not only ensures the closed‐loop systems is globally generalised exponentially stable but also excludes the Zeno behaviour under the triggering condition. Finally, two simulation examples are provided to illustrate the effectiveness of the proposed control strategy.
Improving wind power utilisation under stormy weather condition by risk‐limiting unit commitment
Authors: Qin Zhijun , Cai Ximing , Hou Yunhe
Published: December 2017

Wind power generation has constituted a major body of generation portfolio in many countries. In stormy weather conditions, however, wind power generation would be curtailed due to the over‐speed protection of wind turbines. In this study, the authors propose to apply the risk‐limiting unit commitment (UC) in a rolling framework to improve the efficient utilisation of wind power. The proposed method includes three modules, namely, day‐ahead UC, hourly‐ahead UC, and real‐time load shedding. The first module provides the baseline of hourly dispatch, whereas the latter two serve as recourse means applied during stormy event unfolding. Illustrative examples are provided, demonstrating that the proposed method will reduce the overall generation cost of the time horizon under consideration, as compared to conservative dispatch methods, by postponing the timing of proactive wind curtailment.
A simple approach to CO cooling in molecular clouds
Authors: Whitworth A. P. , Jaffa S. E.
Published: December 2017

Carbon monoxide plays an important role in interstellar molecular clouds, both as a coolant, and as a diagnostic molecule. However, a proper evaluation of the cooling rate due to CO requires a determination of the populations of many levels, the spontaneous and stimulated radiative de-excitation rates between these levels, and the transfer of the emitted multi-line radiation; additionally, this must be done for three isotopologues. It would be useful to have a simple analytic formulation that avoided these complications and the associated computational overhead; this could then be used in situations where CO plays an important role as a coolant, but the details of this role are not the main concern. We derive such a formulation here, by first considering the two asymptotic forms that obtain in the limits of (a) low volume-density and optical depth, and (b) high volume-density and optical depth. These forms are then combined in such a way as to fit the detailed numerical results from Goldsmith & Langer (1978, ApJ, 222, 881; hereafter GL78). The GL78 results cover low temperatures, and a range of physical conditions where the interplay of thermal and sub-thermal excitation, optical-depth effects, and the contributions from rare isotopologues, are all important. The fit is obtained using the Metropolis-Hastings method, and reproduces the results of GL78 well. It is a purely local and analytic function of state — specifically a function of the density, ρ, isothermal sound speed, a, CO abundance, XCO, and velocity divergence, ∇⋅υ. As an illustration of its use, we consider the cooling layer following a slow steady non-magnetic planar J-shock. We show that, in this idealised configuration, if the post-shock cooling is dominated by CO and its isotopologues, the thickness of the post-shock cooling layer is very small and approximately independent of the pre-shock velocity, υo, or pre-shock isothermal sound speed, ao.
Low-grade Endometrial Stromal Sarcoma with Unusual Metastasis to the Skull
Authors: Araújo Júnior Antonio , Arlant Pedro , Salvestrini Júnior Arnaldo , Fernandez Angelo , Docema Marcos , Mattedi Rômulo , Silveira Thales , Caldas José , Fazzito Mirella
Published: December 2017

Background Endometrial stromal sarcomas (ESSs) are the second most common uterine sarcomas. Although ESSs are often indolent, they have metastatic potential. To the best of our knowledge, there are only three reports of brain metastasis, and the present report is the first to describe a late skull metastasis of an ESS.

Case Report We describe the case of a 51-year-old woman who presented abnormal vaginal bleeding 14 years ago; she was diagnosed with an uterine mass and submitted to a hysterectomy. One year ago she presented ESS lung metastasis followed by a left parietal calvarial metastasis. The optimal treatment for metastatic ESS is controversial, but the use of progesterone and aromatase inhibitors is advisable.
Pre- und Probiotika – Wann der Einsatz bei Hund und Katze sinnvoll ist
Authors: Wichert Brigitta
Published: December 2017

Der Einsatz von Pre- und vor allem Probiotika bei Hunden und Katzen wurde vielfach untersucht. Der
Beitrag gibt eine Übersicht über die Definitionen, die rechtliche Situation und den in verschiedenen
Studien untersuchte Gabe von Pre- und Probiotika. Insbesondere die Wirkungen der Pre- und Probiotika auf
den Intestinaltrakt und auf das Immunsystem weisen auf vielfältige Einsatzmöglichkeiten hin.
Homöopathie bei klimakterischen Beschwerden
Authors: Boeddrich Ute
Published: December 2017

Das Klimakterium der Frau kann, muss aber nicht zu einer Krise führen. Symptome wie Hitzewallungen, Schlaflosigkeit, Stimmungsschwankungen
bis hin zu Depressionen und Phobien lassen sich meist positiv mit Homöopathie in Kombination mit naturheilkundlichen Methoden der
Ordnungstherapie behandeln. Es kommen homöopathische Einzelmittel oder sogenannte fixe Kombinationen zum Einsatz. Ergänzend können außerdem
Phytotherapeutika und Verfahren aus der Komplementärmedizin eingesetzt werden. Sollten die genannten Maßnahmen nicht ausreichen, lassen sich
naturidentische Hormone oder konventionelle Hormongaben in den diversen Darreichungsformen wie Gels, Pflaster oder Tabletten für einen
begrenzten Zeitraum hilfreich nutzen.
Fehler und Schwächen in der Berichterstattung über epidemiologische Studien in Printmedien: Das Beispiel „Fleischkonsum und Darmkrebs“
Authors: Kowall Bernd , Stang Andreas
Published: December 2017

Hintergrund Über epidemiologische Studien wird häufig in den Medien berichtet, weil die Ergebnisse für viele Menschen von unmittelbarem Interesse sind. Es soll beispielhaft untersucht werden, ob die Ergebnisse epidemiologischer Studien in Printmedien verständlich und korrekt dargestellt werden.

Methode Sämtliche Berichte aus 13 ausgewählten deutschen Printmedien zum Thema Fleischkonsum und Darmkrebs, die im Anschluss an eine Pressemitteilung der IARC (International Agency for Research on Cancer) vom 26.10.2015 erschienen sind, werden unter dem Gesichtspunkt ihrer Verständlichkeit und Korrektheit ausgewertet. Zudem wird untersucht, nach welchen Kriterien die Printmedien die Aussagekraft der Forschungsergebnisse bewerten.

Ergebnisse 11 der 13 Printmedien übernahmen die Formulierung aus der Pressemitteilung, in der ein relatives Risiko angegeben wurde (18% Erhöhung des Darmkrebsrisikos pro 50 Gramm zusätzlichem Konsum von verarbeitetem Fleisch pro Tag). Da diese Formulierung von vielen Lesern möglicherweise als Erhöhung des absoluten Risikos um 18 Prozentpunkte missverstanden wird, ist die Angabe von absoluten Risiken sinnvoller. Absolute Risiken werden jedoch nur von 6 Printmedien korrekt angegeben. 5 Printmedien formulieren fälschlicherweise Schwellenwerte für den Fleischkonsum. Weitere Fehler liegen darin, die Indexgruppe ungenau zu beschreiben (etwa: „exzessive Fleischesser“ ohne Grammangabe), die Referenzgruppe nicht eindeutig zu benennen und darin, Zeiträume, für die ein Risiko berechnet wurde, nicht anzugeben. Wissenschaftsinterne Kriterien für die Bewertung der Qualität der epidemiologischen Studien wie Confounding und die Präzision bei der Erhebung des Fleischkonsums werden selten angeführt.

Schlussfolgerung Schon in Pressemitteilungen sollte auf eine verständliche Darstellung von Maßzahlen, Effektschätzern und wichtigen Fehlerquellen geachtet werden. Im konkreten Beispiel hätte eine höhere Qualität der Pressemitteilung der IARC – insbesondere das Benennen absoluter anstelle relativer Risiken – vermutlich eine weniger missverständliche Berichterstattung in den Printmedien zur Folge gehabt.
Ultraschall unter der Geburt: Eine systematische Analyse des Höhenstandes des kindlichen Kopfes in der Eröffnungsperiode der Geburt
Authors: Kohls Fabian , Brodowski Lars , Kuehnle Elna , Kniebusch Nadine , Kalache Karim , Weichert Alexander
Published: December 2017

Einleitung Die Höhenstandsbestimmung des fetalen Kopfes hat Einfluss auf das geburtshilfliche Management. Ziel der Studie war es mithilfe des angle of progression (AOP) in der Eröffnungsphase eine Aussage über Geburtsdauer und Geburtsmodus zu treffen.

Methodik Dies war eine prospektive Studie. Einschlusskriterien waren Einlingsschwangerschaften, spontan-vaginale Geburt, fetale Schädellage, Primi- und Multiparae und Patientinnen mit Periduralanästhesie (PDA). Einflussfaktoren wie Kopfumfang, Geburtsgewicht, Oxytocingabe, Periduralanästhesie, Parität wurden bestimmt und den Einfluss auf den AOP analysiert sowie drei Berechnungsvarianten erstellt.

Ergebnis 30 Patientinnen wurden eingeschlossen. Der Anteil an spontan-vaginalen Geburten lag bei 90%, die der vaginal-operativen bei 10%. Der Durchschnittswinkel des AOP lag bei den spontan-vaginalen Entbindungen bei einer Muttermundsweite <5 cm bei 100,9°, bei >5 cm bei 125,3°. Bei den vaginal-operativen Entbindungen lag der Durchschnittswinkel bei <5 cm bei 93°, bei>5 cm bei 113,9°. Nur die erste Berechnung AOP 1/Muttermundöffnung in cm bei der 1. Messung zeigt eine Tendenz zur Geburtsdauer, aber nicht zum Entbindungsmodus.

Fazit für die Praxis Die prognostische Aussagefähigkeit des Ultraschalls unter der Geburt in der Eröffnungsphase lässt Tendenzen zur Geburtsdauer erkennen.
Effect of collisions on Weibel instability with anisotropic electron distributions
Authors: Aman-ur-Rehman  , Ali Shan Shaukat , Majeed Tariq
Published: December 2017

Using kinetic approach, the effect of electron–ion collisions on Weibel instability has been investigated for three different types of anisotropic distribution functions (i.e., bi-kappa, bi-Maxellian, and product bi-kappa). It is found that the presence of electron–ion collisions has a negative effect on the growth rate of Weibel instability. By using analytical analysis, it has been found that the growth rate of the collisional plasma becomes negative if the electron–ion collision frequency becomes higher than the growth rate of the Weibel instability for a collisionless plasma while keeping all the other parameters same. The impact of electron–ion collisions has also been studied on the temperature anisotropy parameter τ(=T⊥/T||) threshold required for making the growth rate of the Weibel instability positive for all the three distribution functions. The illustrations show that for higher spectral index κ||=κ>4, the temperature anisotropy threshold is same for all the three distribution functions; however, for lower κ||=κ<4, the threshold conditions are different for the bi-kappa as compared to those found for the other two distribution functions. The boundaries between the stable and unstable regions of bi-kappa and product bi-kappa distributions have been found in the presence of collisions. In the presence of collisions, the boundary curve for product bi-kappa is similar to that we get in the absence of collisions. However, the temperature anisotropy threshold parameters are higher for collisional plasma as compared to those obtained for the collisionless plasma. The boundary curve for bi-kappa distribution function in the presence of collisions is significantly different from the boundary curve formed in the absence of collisions. In the presence of collisions, the temperature anisotropy threshold increases very rapidly when the spectral index is <2.
Directional linearly polarized terahertz emission from argon clusters irradiated by noncollinear double-pulse beams
Authors: Mori Kazuaki , Hashida Masaki , Nagashima Takeshi , Li Dazhi , Teramoto Kensuke , Nakamiya Yoshihide , Inoue Shunsuke , Sakabe Shuji
Published: December 2017

It has been demonstrated that the interaction between argon clusters and intense femtosecond double laser pulses with appropriate intervals in time and space provides important properties for terahertz electromagnetic wave generation, namely, high forward directivity, power enhancement, and linear polarization with a variable direction. Irradiating argon clusters with double pulses (1 and 3 mJ, 40 fs, 810 nm) in 133-ps and 40-μm intervals results in terahertz wave emission in the forward direction that is 10 times greater than that for a single pulse. The polarization direction of terahertz electromagnetic waves can be varied by changing the relative focal positions of the first and second pulses.
A scintillating plastic fiber array and multiplexer based 384-channel fast neutron spectrometer
Authors: Sun Liyang , Zhuang Kai , Wang Xiaoming , An Heng , Zeng Fanjian , Yang Mingjie , Zhou Wei , Xue YuXiong , Zhang Zhiming , Wang Yingjie , Li Daowu , Feng Baotong , Wang Peilin , Li Xiaohui , Cai Jiale , Qin Xiu Bo , Wei Long
Published: December 2017

A fast neutron detection system based on a scintillating plastic fiber array and multiplexer was designed to measure the spectrum of fast neutrons ranged 10 MeV–100 MeV. With the method of nuclear recoil, the energy of incident neutron was determined by measuring the recoil proton track and deposited energy in scintillating plastic fibers. The detection system was composed of a scintillating plastic fiber array, 6 position sensitive photomultiplier tubes, and a high-density readout electronics based on the multiplexer. The scintillating plastic fiber array was made as a staggered structure with two kinds of fibers in different sizes (0.5 mm-square fiber and 3 mm-square fiber). The structure provided a wider detection energy range and better detection efficiency than arrays made with uniform plastic fibers. A dedicated digital electronics system was well designed to control the whole readout system to provide 384-channel signal processing. The detector had a 48 mm × 48 mm effective detection area and a mechanical size of 34 cm × 34 cm × 27 cm. In the simulation of the detector model performance, the system gave an energy resolution of 23%-35% for neutrons ranged 10 MeV-100 MeV. Experimental results showed that the detector had a good energy linearity and energy resolutions were, respectively, 35.82% at 14.817 MeV, 36.84% at 21.264 MeV, 35.90% at 23.069 MeV, and 32.90% at 24.220 MeV. The optimized prototype model had potential in increasing fast neutron detection performance.
Phase shifter tuned by varying the spring constant of a nanomechanical cantilever
Authors: Tanaka H. , Ozaki T. , Ohno Y. , Tadokoro Y.
Published: December 2017

This paper presents a theoretical study of an adaptive microwave phase shifter based on a nanomechanical resonator. The phase shifter can be tuned to provide an arbitrary phase rotation in the range between –90° and 90° by adjusting the bias voltage applied to the resonator. An analytical model is developed to reveal the underlying mechanism of the phase shifter. It is also analytically demonstrated that the operating frequency can be selected by adjusting the bias voltage. In addition, it is found that the bandwidth is tunable via the quality factor for the cantilever.
Controlling n-type conductivity of β-Ga2O3 by Nb doping
Authors: Zhou Wei , Xia Changtai , Sai Qinglin , Zhang Hongzhe
Published: December 2017

It has been confirmed that Si, Sn, and Ge are effective n-type dopants for β-Ga2O3. This letter shows that Nb doping is also a viable method for controlling the electrical resistivity and carrier density of β-Ga2O3, corresponding to the theoretical calculations about the doping of Ga2O3 with Nb [H. Peelaers and C. G. Van de Walle, Phys. Rev. B 94(19), 4 (2016)]. β-Ga2O3 single crystals with different Nb concentrations were grown by the optical floating zone method. The electrical resistivity can be varied from 3.6 × 102 Ω cm to 5.5 × 10−3 Ω cm by increasing the Nb doping concentration, and the related free carrier concentration increases from 9.55 × 1016 cm−3 to 1.8 × 1019 cm−3. The transmittance spectra and photoluminescence spectra were measured to systematically study the optical properties of Nb-doped β-Ga2O3 single crystals. The strong absorption near the IR region in the crystals is related to the increase in conductive electrons, and the decrease in blue luminescence intensity indicates a decrease in the VO concentration induced by increasing the carrier concentration.
A metal-insulator transition study of VO2 thin films grown on sapphire substrates
Authors: Yu Shifeng , Wang Shuyu , Lu Ming , Zuo Lei
Published: December 2017

Vanadium thin films were deposited on sapphire substrates by DC magnetron sputtering and then oxidized in a tube furnace filled with oxygen under different temperatures and oxygen flow rates. The significant influence of the oxygen flow rate and oxidation temperature on the electrical and structural properties of the vanadium oxide thin films were investigated systematically. It shows the pure vanadium dioxide (VO2) state can only be obtained in a very narrow temperature and oxygen flow rate range. The resistivity change during the metal-insulator transition varies from 0.2 to 4 orders of magnitude depending on the oxidation condition. Large thermal hysteresis during the metal-insulator phase transition was observed during the transition compared to the results in literature. Proper oxidation conditions can significantly reduce the thermal hysteresis. The fabricated VO2 thin films showed the potential to be applied in the development of electrical sensors and other smart devices.
Wavefront modulation and controlling for Lamb waves using surface bonded slice lenses
Authors: Tian Zhenhua , Yu Lingyu
Published: December 2017

There is a growing interest in controlling the propagation of Lamb waves to achieve better performance for structural health monitoring and nondestructive evaluation. In this study, we present new methods of controlling Lamb waves using simple slice lenses through wavefront modulation. The lenses are made of metal slices with designed shapes. Once bonded on plates, the lenses modify the effective plate thickness, and therefore change the Lamb wave characteristics such as the wavenumber and phase velocity, providing convenient ways of modulating wavefront and controlling Lamb waves in plates. Numerically and experimentally, we demonstrated that a straight wavefront A0 mode can be focused on the desired focal point using a plano-concave aspherical lens. We also demonstrated that the A0 mode can be steered with different frequency components steered to different directions using a simple prism made of metal slices. The work shows that such simple slice lenses provide easy ways for controlling Lamb waves, and have a great potential for Lamb wave based applications.
Microwave beam steering of planar antennas by hybrid phase gradient metasurface structure under spherical wave illumination
Authors: Katare Kranti Kumar , Biswas Animesh , Akhtar M. Jaleel
Published: December 2017

To facilitate the microwave beam steering of planar antennas in both elevation and azimuth planes, a radially gradient quasi-transparent hybrid metasurface (RGHMS) structure is proposed. The circular aperture of RGHMS is comprised of two different phase profiles in the single structure. Half of the circular aperture introduces a gradient phase shift, whereas the other half provides a constant phase shift to the incident spherical wave. Since the obtained wavefront modulation for the beam tilting is realized using the combination of aforementioned phase profiles in a single metasurface (MS), it is considered as a hybrid structure. The proposed circular RGHMS with a radius of 1.2λ0 is placed at a height of 0.43λ0 from the feed antenna by considering the geometrical centers of RGHMS and antenna aperture coinciding with each other. The in-plane translation of the RGHMS modulates the wavefront of the incident wave, which results in 0° to 18° beam steering of planar antenna in the elevation plane. Moreover, in-plane rotation of RGHMS around the antenna axis facilitates the beam steering in the azimuth plane with a full 360° azimuthal coverage. The proposed structure is designed at the center frequency of 10 GHz and introduces uniform beam shapes with the gain of 12.3–14.3 dBi during the beam steering. The strategy of combining two different types of phase profile in a single MS eludes the requirement of the phase correcting lens, and thus can directly be illuminated through the spherical wavefront of antenna in the near field. Moreover, the microwave beam steering in both planes with fairly high gain and compact configuration is revealed.
Mesoscopic-microscopic spatial stochastic simulation with automatic system partitioning
Authors: Hellander Stefan , Hellander Andreas , Petzold Linda
Published: December 2017

The reaction-diffusion master equation (RDME) is a model that allows for efficient on-lattice simulation of spatially resolved stochastic chemical kinetics. Compared to off-lattice hard-sphere simulations with Brownian dynamics or Green’s function reaction dynamics, the RDME can be orders of magnitude faster if the lattice spacing can be chosen coarse enough. However, strongly diffusion-controlled reactions mandate a very fine mesh resolution for acceptable accuracy. It is common that reactions in the same model differ in their degree of diffusion control and therefore require different degrees of mesh resolution. This renders mesoscopic simulation inefficient for systems with multiscale properties. Mesoscopic-microscopic hybrid methods address this problem by resolving the most challenging reactions with a microscale, off-lattice simulation. However, all methods to date require manual partitioning of a system, effectively limiting their usefulness as “black-box” simulation codes. In this paper, we propose a hybrid simulation algorithm with automatic system partitioning based on indirect a priori error estimates. We demonstrate the accuracy and efficiency of the method on models of diffusion-controlled networks in 3D.
Novel rubidium poly-nitrogen materials at high pressure
Authors: Williams Ashley S. , Steele Brad A. , Oleynik Ivan I.
Published: December 2017

First-principles crystal structure search is performed to predict novel rubidium poly-nitrogen materials at high pressure by varying the stoichiometry, i.e., relative quantities of the constituent rubidium and nitrogen atoms. Three compounds of high nitrogen content, RbN5, RbN2, and Rb4N6, are discovered. Rubidium pentazolate (RbN5) becomes thermodynamically stable at pressures above 30 GPa. The charge transfer from Rb to N atoms enables aromaticity in cyclo-N5− while increasing the ionic bonding in the crystal. Rubidium pentazolate can be synthesized by compressing rubidium azide (RbN3) and nitrogen (N2) precursors above 9.42 GPa, and its experimental discovery is aided by calculating the Raman spectrum and identifying the features attributed to N5− modes. The two other interesting compounds, RbN2 containing infinitely long single-bonded nitrogen chains and Rb4N6 consisting of single-bonded N6 hexazine rings, become thermodynamically stable at pressures exceeding 60 GPa. In addition to the compounds with high nitrogen content, Rb3N3, a new compound with 1:1 RbN stoichiometry containing bent N3 azides is found to exist at high pressures.
Origin of the dielectric abnormities and tunable dielectric properties in doped KTN single crystals
Authors: Wu You , Li Jun , Bai Han , Hong Yang , Shi Kouzhong , Zhou Zhongxiang , Guo Ruyan , Bhalla Amar S.
Published: December 2017

The dielectric properties of (Fe,Li)-codoped KTa1−xNbxO3 single crystals have been measured, and the origin of the dielectric abnormities was discussed in detail. In the low temperature range of 20–100 K for each of the samples, the relaxation R1 is attributed to the electrons-activating/freezing in the defect-dipoles while the dielectric abnormity is contributed by the relaxation R1 and the two phase transitions (PR-O and PO-T). The relaxation R2 in the range of 100–200 K is likely due to the reorientation of the dipolar structure Fe3+-Oi2− as well as the formation of a small number of non-localized polaronic particles. In the high temperature range of 200–450 K, controlling the temperature interval between the first-order phase transition P1 and the diffuse transition P2 could make permittivity tunable in values and thermal stability through simply changing the composition parameter x in the doped KTN single crystals. This work provides us an effective way to design optimal dielectric materials for research and applications.
Low-power bistability in graphene-comprising 3D photonic resonant circuits
Authors: Christopoulos Thomas , Tsilipakos Odysseas , Kriezis Emmanouil E.
Published: December 2017

Practical graphene-comprising resonant structures are proposed for high-quality Kerr-induced bistability with a low input power. Two structures are designed for operation in the far-infrared (FIR) and near-infrared (NIR) frequency regimes, respectively. The nonlinear response is studied by utilizing a theoretical framework combining perturbation theory and coupled-mode theory, capable of accurately and efficiently modeling resonant structures with dispersive bulk and sheet materials. The FIR system is based on a side-coupled graphene-nanoribbon ring resonator, formed by applying a bias voltage between a uniform graphene sheet and an uneven silicon substrate. By optimizing the system geometry, we demonstrate bistable response with a theoretically infinite extinction ratio between states and an operating power of only 400 μW at 10 THz. In the NIR circuit, a silicon photonic ring resonator is overlaid with a graphene sheet. The silicon-slot geometry is judiciously chosen to maximize the field overlap with graphene, resulting in low power requirements of 90 mW at 1.55 μm. In both cases, nonlinearity stems from the instantaneous Kerr effect in graphene, allowing for ultra-fast response. Combining low input power and fast response times, the proposed components highlight the potential of graphene for nonlinear applications over a broad spectral range.
The singularity of the two-fluid plasma equations, its relations to boundary conditions, and the numerical solution of these equations
Authors: Valentini H.-B. , Kaiser D.
Published: December 2017

The equations describing the two-fluid model of a plasma contain a removable singularity at the ion sound velocity. Taking into account a non-zero ion temperature, the irregular point is located between the centre of the plasma and the wall. It is advisable to treat the inner interval between the centre and the irregular point and the outer one between this point and the wall separately. Taylor series yield a smooth solution through this point. Readily manageable numerical solution methods are stable in the outer interval but very unstable in the inner one. The domain of the parameters is determined in which the one-fluid model results in a very useful approximation throughout the inner interval. With it, the space charge density can also be estimated well. At the irregular point, the missing accurate boundary values of the two-fluid equations required for both the intervals can be determined by means of a few steps of a shooting method starting at the results of the one-fluid model. The instability of the treated differential equations ascertained in the inner interval becomes comprehensible by using the Lyapunov criterion. The results obtained in the inner interval can be used as start values for other numerical methods to improve the results. The methods explained here allow us to obtain usable numerical results for the two-fluid model in a large interesting domain by a relatively little effort.