bluuebunny/crossref_metadata_2025 huggingface dataset:
Long non-coding RNA HOTAIR promotes tumorigenesis and forecasts a poor prognosis in cholangiocarcinoma
Authors: Qin Wei , Kang Pengcheng , Xu Yi , Leng Kaiming , Li Zhenglong , Huang Lining , Gao Jianjun , Cui Yunfu , Zhong Xiangyu
Published: August 2018

Cholangiocarcinoma (CCA) arising from the neoplastic transformation of cholangiocytes with increasing incidence in the worldwide. Unfortunately, a large amount of CCA patients lost their chance for surgery because it is hard to diagnose in the early stages. Long non-coding RNAs (lncRNAs) is closely associated with development and progression of various malignant tumors. Hox transcript antisense intergenic (HOTAIR), a negative prognostic factor for patients with gastric, liver and pancreatic carcinoma. Its transcription levels and functional roles in CCA is still unknown. Therefore, we aimed to explore the effect of HOTAIR in CCA including cell proliferation, apoptosis, migration, invasion and epithelial-to-mesenchymal transition (EMT). The results showed that HOTAIR was highly expressed both in CCA tissue samples and cell lines compared with corresponding normal bile duct tissues and Human intrahepatic biliary epithelial cells (HIBEC). Its overexpression was closely correlated with Tumor size, TNM stage and postoperative recurrence in CCA patients. Moreover, up-regulation of HOTAIR has correlation with prognosis in CCA patients. Knockdown of HOTAIR by siRNAs significantly decreased the migration and invasion but increased apoptosis of CCA cells in vitro. Overall, our study revealed that HOTAIR may play as a new potential therapeutic target and forecast poor prognosis for this fatal disease.
Exciton physics and device application of two-dimensional transition metal dichalcogenide semiconductors
Authors: Mueller Thomas , Malic Ermin
Published: August 2018

Two-dimensional group-VI transition metal dichalcogenide semiconductors, such as MoS2, WSe2, and others, exhibit strong light-matter coupling and possess direct band gaps in the infrared and visible spectral regimes, making them potentially interesting candidates for various applications in optics and optoelectronics. Here, we review their optical and optoelectronic properties with emphasis on exciton physics and devices. As excitons are tightly bound in these materials and dominate the optical response even at room-temperature, their properties are examined in depth in the first part of this article. We discuss the remarkably versatile excitonic landscape, including bright, dark, localized and interlayer excitons. In the second part, we provide an overview on the progress in optoelectronic device applications, such as electrically driven light emitters, photovoltaic solar cells, photodetectors, and opto-valleytronic devices, again bearing in mind the prominent role of excitonic effects. We conclude with a brief discussion on challenges that remain to be addressed to exploit the full potential of transition metal dichalcogenide semiconductors in possible exciton-based applications.
Correction: Corrigendum: Expanded CURB-65: a new score system predicts severity of community-acquired pneumonia with superior efficiency
Authors: Liu Jin-liang , Xu Feng , Zhou Hui , Wu Xue-jie , Shi Ling-xian , Lu Rui-qing , Farcomeni Alessio , Venditti Mario , Zhao Ying-li , Luo Shu-ya , Dong Xiao-jun , Falcone Marco
Published: August 2018

Scientific Reports 6: Article number: 22911; published online: 18 March 2016; updated: 09 August 2018 This Article contains typographical errors in Table 2 in the Multivariate logistic regression analysis section. The OR values for Platelet count, Glucose level, WBC count and C-reactive protein level are duplicated from their partial regression coefficients (β).
An anion receptor that facilitates transmembrane proton–anion symport by deprotonating its sulfonamide N–H proton
Authors: Shinde Sopan Valiba , Talukdar Pinaki
Published: August 2018

Indole-based amide-sulfonamide derivatives were synthesized. The X-ray crystal structure and chloride binding studies in solution showed a 1 : 1 stoichiometry. The ion transport study indicated the proton–anion symport across the lipid bilayer membrane.
Metal coordination induced ring contraction of porphyrin derivatives
Authors: Patra Bratati , Sobottka Sebastian , Mondal Sruti , Sarkar Biprajit , Kar Sanjib
Published: August 2018

Ferrocenyl-porphyrin derivatives upon treatment with silver acetate at room temperature show ring contraction followed by Ag-chelation.
Solid-state characterization and solubility enhancement of apremilast drug–drug cocrystals
Authors: Wang Feng-Yuan , Zhang Qi , Zhang Zaiyong , Gong Xiaoyi , Wang Jian-Rong , Mei Xuefeng
Published: August 2018

Three isostructural cocrystals of apremilast with nicotinamide, caffeine, and acetylsalicylic acid were successfully designed and synthesized on the basis of its solvated structures.
High Curie temperature and half-metallicity in an atomically thin main group-based boron phosphide system: long range ferromagnetism
Authors: Bhattacharyya Gargee , Choudhuri Indrani , Pathak Biswarup
Published: August 2018

In this work, we have designed a main group-based novel ferromagnetic half-metallic material with a high Curie temperature for spintronics.
The local structure in the BmimPF6/acetonitrile mixture: the charge distribution effect
Authors: Koverga Volodymyr , Kalugin Oleg N. , Miannay François-Alexandre , Smortsova Yevheniia , Goloviznina Kateryna , Marekha Bogdan , Jedlovszky Pal , Idrissi Abdenacer
Published: August 2018

The effect of the charge distribution on the local structure in the binary mixture of 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) ionic liquid and acetonitrile is investigated over the entire composition range.
Ultrafast ring closing of a diarylethene-based photoswitchable nucleoside
Authors: Li Yang , Pérez Lustres J. Luis , Volpp Hans-Robert , Buckup Tiago , Kolmar Theresa , Jäschke Andres , Motzkus Marcus
Published: August 2018

Ring closing of a diarylethene nucleoside occurs ballistically. IVR and cooling ultimately drag the population to the product well.
Optical properties and structure of Ag-doped InP quantum dots prepared by a phosphine synthetic route
Authors: Vinokurov Alexander , Chernysheva Galina , Mordvinova Natalia , Dorofeev Sergey
Published: August 2018

InP QDs doping by silver via a PH3-based synthetic route results in the formation of Ag-doped InP QDs and core–shell Ag/InP nanostructures.
A multifunctional Co-based metal–organic framework: heterogeneous catalysis, chemiluminescence sensing and moisture-dependent solvatochromism
Authors: Xie Ming-Hua , Wang Ya , Li Ruo-Fei , Dong Peng-Yu , Hou Gui-Hua , Shao Rong , Xi Xin-Guo , Guan Rong-Feng , Yang Xiu-Li
Published: August 2018

A highly integrated metal–organic framework with multiple applications was studied both experimentally and theoretically.
Effects of elevated production of autochthonous dissolved organic matter on the freely dissolved concentration of cadmium
Authors: Dong Qianqian , Wang Feng , Xiao Yihua , Li Penghui , Huang Qinghui
Published: August 2018

In this study, we investigated the elevated production of autochthonous dissolved organic matter driven by eutrophication and its effects on cadmium bioavailability.
High-throughput single-molecule bioassay using micro-reactor arrays with a concentration gradient of target molecules
Authors: Watanabe Rikiya , Komatsu Toru , Sakamoto Shingo , Urano Yasuteru , Noji Hiroyuki
Published: August 2018

We developed micro-reactor arrays with a concentration gradient of target molecules for high-throughput single-molecule bioassay.
Frequency-enhanced transferrin receptor antibody-labelled microfluidic chip (FETAL-Chip) enables efficient enrichment of circulating nucleated red blood cells for non-invasive prenatal diagnosis
Authors: Zhang Huimin , Yang Yuanyuan , Li Xingrui , Shi Yuanzhi , Hu Bin , An Yuan , Zhu Zhi , Hong Guolin , Yang Chaoyong James
Published: August 2018

We proposed a FETAL-Chip for efficient enrichment of cNRBCs, which offers great potential for NIPD.
Modification of the fluorinated tin oxide/electron-transporting material interface by a strong reductant and its effect on perovskite solar cell efficiency
Authors: Pulvirenti Federico , Wegner Berthold , Noel Nakita K. , Mazzotta Giulio , Hill Rebecca , Patel Jay B. , Herz Laura M. , Johnston Michael B. , Riede Moritz K. , Snaith Henry J. , Koch Norbert , Barlow Stephen , Marder Seth R.
Published: August 2018

An organometallic reductant affords ohmic contact between FTO and a perylene electron-transport material.
New model of metalloantibiotic: synthesis, structure and biological activity of a zinc(ii) mononuclear complex carrying two enrofloxacin and sulfadiazine antibiotics
Authors: Boughougal Amina , Cherchali Fatma Zohra , Messai Amel , Attik Nina , Decoret Dominique , Hologne Maggy , Sanglar Corinne , Pilet Guillaume , Tommasino Jean Bernard , Luneau Dominique
Published: August 2018

Synthesis of a new model of the Zn-based complex with two complementary antibiotics (sulfonamide and quinolone).
Native chemical ligation at methionine bioisostere norleucine allows for N-terminal chemical protein ligation
Authors: Xin Bo-Tao , van Tol Bianca D. M. , Ovaa Huib , Geurink Paul P.
Published: August 2018

γ-Thionorleucine is synthesized and used for N-terminal chemical protein modification by native chemical ligation–desulfurization to prepare linear diubiquitin.
Phosphite-catalyzed alkoxycarbonylation of aryl diazonium salts
Authors: Xu Jian-Xing , Franke Robert , Wu Xiao-Feng
Published: August 2018

In this communication, an interesting phosphite-catalyzed alkoxycarbonylation of aryl diazonium salts has been reported.
Microliter viscometry using a bright-field microscope: η-DDM
Authors: Escobedo-Sánchez M. A. , Segovia-Gutiérrez J. P. , Zuccolotto-Bernez A. B. , Hansen J. , Marciniak C. C. , Sachowsky K. , Platten F. , Egelhaaf S. U.
Published: August 2018

Bright-field Differential Dynamic Microscopy is applied to determine the steady-shear viscosity via the intermediate scattering function.
Long-range stress correlations in viscoelastic and glass-forming fluids
Authors: Klochko L. , Baschnagel J. , Wittmer J. P. , Semenov A. N.
Published: August 2018

In the present paper we show that viscoelastic liquids are characterized by pronounced long-range dynamical correlations of mechanical stress.
A rapidly recoverable shape memory polymer with a topologically well-controlled poly(ethyl methacrylate) structure
Authors: Lai Jingjuan , Li Xingjian , Wu Ruiqing , Deng Jinni , Pan Yi , Zheng Zhaohui , Ding Xiaobin
Published: August 2018

A topologically well-controlled network shape memory poly(ethyl methacrylate) (CN-SMPEMA) is designed and fabricated by introducing two tetra-armed functional structures simultaneously as well-defined structure units.
Metamaterial‐based circularly polarised antenna employing ENG‐TL with enhanced bandwidth for WLAN applications
Authors: Ameen M. , Chaudhary R.K.
Published: August 2018

This work explains the design and development of a low profile and compact single probe‐fed metamaterial (MTM)‐based circularly polarised (CP) antenna using the modified rectangular patch with two pairs of spiral strips and vias for 5.2/5.8 GHz WLAN applications. The intended CP antenna mainly consists of two pairs of radiators and each radiator is realised by using epsilon negative (ENG) transmission line (TL) to generate zeroth‐order resonance. CP characteristics are achieved by placing two radiators for x‐polarised wave are orthogonally aligned to the other two radiators for y‐polarised wave. The antenna radiating element offers a compact size of 0.24λ0 × 0.22λ0 with a low profile of 0.04λ0 at 5.5 GHz. To confirm the characteristics of the intended MTM CP antenna design, the designed antenna is fabricated and measured. Measurement results show that the antenna obtains −10 dB impedance bandwidth of 610 MHz (10.86%) which is 2.3 times larger than the standard microstrip patch antenna and axial ratio bandwidth of 140 MHz (2.54%) is obtained.
3D MIMO imaging architecture for walk through personnel security screening
Authors: Zhou Ye , Yu Junjun , Pan Liuyan , Wang Yi , Cao Qunsheng
Published: August 2018

A high‐resolution imaging system for short‐range personnel security screening based on a novel multiple‐input‐multiple‐output (MIMO) array is presented. It overcomes the problem of specular reflection which occurs in the most state‐of‐the‐art mono‐static‐based configuration. Prior to the state‐of‐the‐art portal‐based architecture, this system is able to reconstruct three‐dimensional (3D) image of the whole body and detect a concealed weapon in secret while passenger walking through the hallway or intersection, which is a potential for realising a reconfigurable system to monitor the marching crowd. The architecture consists of four transmitter columns and two receiver circles, illumination area which covers the most concerned part of the human body. The reduced number of sensors and no moving part characteristic make authors’ system cost efficient and robust. A ray‐tracing technique is applied to fast estimate its illumination and imaging performance. Several numerical experiments based on the frequency modulated continuous wave model with 10–25 GHz frequency sweeping are proposed to reach both azimuth and range 1 cm resolution. 3D results of these experiments show that authors’ system works well on whole‐body imaging and threat object detection.
Space charge and conductivity measurement of XLPE nanocomposites for HVDC insulation–permittivity as a nanofiller selection parameter
Authors: Sharad Paramane Ashish , Sathish Kumar Kannaiah , Ahmad Mohd Hafizi , Mohamed Piah Mohamed Afendi
Published: August 2018

Cross‐linked polyethylene (XLPE) insulation is successfully used for high‐voltage AC transmission. However, it is still under development for high‐voltage DC application due to space charge accumulation, which distorts the internal electrical field distribution and leads to its aging/failure. Therefore, the space charge should be measured and carefully analysed. On the other side, conductivity measurement helps to forecast the degradation probability of the insulation. Higher conductivity represents the severe degradation. Nanofiller addition, such as SiO2, TiO2, MgO and so on (<5 wt%), particularly surface‐modified nanofiller due to its better dispersion significantly suppresses the space charge accumulation and conductivity. Nevertheless, the choice of suitable nanofiller has still remained a challenge. With this context, space charge and conductivity of XLPE‐silica and XLPE‐magnesium oxide (MgO) surface‐modified nanocomposites are measured. This study proposes a parameter for nanofiller selection that will deliver optimal properties for the intended application. Results show that nanocomposites with higher nanofiller permittivity (i.e. MgO) have less space charge accumulation and low conductivity and are justified with the help of a band gap theory model.
Robust meter placement for active distribution state estimation using a new multi‐objective optimisation model
Authors: Prasad Sachidananda , Vinod Kumar Dulla Mallesham
Published: August 2018

In this study, a new multi‐objective optimisation model is developed to deploy phasor measurement units (PMUs) and intelligent electronic devices (IEDs) optimally in an active distribution network for state estimation. Three objective functions are considered in this optimisation problem such as the total cost of PMUs and IEDs, and the root mean square value of state estimation error. Since conflicting objectives are considered; to find the optimal locations of the devices, the meter placement problem is developed in a multi‐objective framework to get compromised solution. The best compromised solution is obtained using multi‐objective hybrid particle swarm optimisation (PSO)‐Krill Herd algorithm (KHA). Furthermore, the reliability of the proposed meter placement technique is tested under load and generators’ output variations. All distributed generations (DGs) are considered as wind generators and the output of each DG is modelled using Weibull distribution function. The proposed algorithm is tested on IEEE 69‐bus system as well as on a practical Indian 85‐bus system. The obtained results have been compared with traditional PSO, KHA and also with well known non‐dominated sorting genetic algorithm.
Hyaluronic acid coated hollow mesoporous silica nanoparticles for reduction‐triggered drug release
Authors: Zhang Yuanyuan , Cao Xiang , Xiang Shengke , Tong Zhiwei
Published: August 2018

In this work, the reduction‐responsive hyaluronic acid (HA) coated hollow mesoporous silica nanoparticles (HMSNs) were developed for the targeted tumour therapy. First, the anticancer drug doxorubicin was retained inside the central hollow cavities of the HMSNs with high loading efficiency. Meanwhile, the adamantane group was anchored on the surface of the HMSNs using the disulphide bond as the reduction–cleavable linkage. Subsequently, the β‐cyclodextrin (β‐CD) decorated HA was immobilised on the surface of HMSNs by the strong β‐CD/adamantane host–guest interactions. Specifically, the β‐CD acted as the pore caps to block the loaded drug inside, while HA served as the targeting ligand for the effective cancer therapy. Under the intracellular reductive environment, the nanocomposites displayed reduction‐triggered drug release manner. Confocal microscopy observations confirmed the nanocomposites were easily internalised by HeLa cancer cells and released the loaded drug inside. In addition, the cytotoxicity study evidenced that HA decorated nanocomposites exhibited improved biocompatibility and antitumour activity as compared to that without HA modification. Thus, the reduction‐responsive nanocomposites could be promising as a drug delivery platform toward the cancer therapy.
Bei Schmerzen im Bereich des großen Trochanters erzielen Schulung plus Bewegungstherapie mehr allgemeine Verbesserung als Cortison-Injektionen
Authors: Ammer K.
Published: August 2018

Referat zur Arbeit von Mellor R, Bennell K, Grimaldi A, Nicolson P, Kasza J, Hodges P,Wajswelner H, Vicenzino B. Education plus exercise versus corticosteroid injection use versus a wait and see approach on global outcome and pain from gluteal tendinopathy: prospective, single blinded, randomised clinical trial. BMJ 2018; 360: k1662
Timing of Tracheostomy in Intensive Care Unit Patients
Authors: Khammas Ammar , Dawood Mohammed
Published: August 2018

Introduction The ideal timing of tracheostomy in intensive care units (ICUs) for critically ill patients undergoing prolonged mechanical ventilation (MV) is still a controversial issue.

Objectives To determine the proper timing of tracheostomy and its impact on various clinical outcomes of adult patients in ICUs undergoing prolonged MV.

Methods The present study consisted of a sample of 67 ICU adult patients who were submitted to open surgical tracheostomy and divided into two groups: 30 patients in the early tracheostomy (ET) group (within 1–10 days post intubation), and 37 patients in the late tracheostomy (LT) group (within 11–21 days post intubation). The correlation between the timing of tracheostomy of each group and various associated ICU clinical parameters were analyzed.

Results The sample consisted of 61.19% male and 38.81% female patients, with a mean age of 47.263 ± 7.581 years. The mean MV duration in days was 7.91 ± 4.937 standard deviation (SD) in the ET group, and 15.32 ± 7.472 SD in the LT group (p = 0.001), with a mean sedation time of 6.13 ± 4.647 SD in the ET group, and of 11.98 ± 6.596 SD in the LT group (p = 0.001). The duration of the weaning process duration had a mean of 2.75 ± 2.586 SD days in the ET group, and of 5.39 ± 5.817 SD days in the LT group (p = 0.025), with a weaning failure rate of 28.57% in the ET group and 71.42% in the LT group (p = 0.01). The Mean ICU stay was 26.18 ± 4.732 SD in the ET group, and 11.98 ± 6.596 SD in the LT group (p = 0.879), and the incidence of ventilator-associated pneumonia (VAP) of 23.33% in the ET group and of 27.02% in the LT group (p = 0.15).

Conclusion Early tracheostomy had a notable benefit in shortening the duration of the MV, lessening the sedation time and minimizing the risks of weaning failure, but it had no significant impact on both the overall duration of ICU stay and VAP incidence.
An Unusual Case of Noncatamenial Recurrent Pneumothorax
Authors: Kirschbaum Andreas , Greulich Timm , Mirow Nikolas , Bartsch Detlef
Published: August 2018

In a 28-year-old female, seven recurrent pneumothoraces occurred during a period of 2 years despite multiple thoracic interventions, all on the left thoracic side. Despite profound differential diagnostic analysis, the underlying cause remains unclear. An accumulation of conditions in this patient affecting only the left half of the body is remarkable: sinistral glaucoma as an infant, a sinistral pigmentation disorder, and a sinistral Bochdalek hernia.
Surgical Treatment of Cardiac Metastases: Analysis of a 13-Year Single-Center Experience
Authors: Mkalaluh Sabreen , Szczechowicz Marcin , Torabi Saeed , Sabashnikov Anton , Mashhour Ahmed , Karck Matthias , Weymann Alexander
Published: August 2018

Background Cardiac metastases are more common than primary malignant tumors of the heart and are usually treated surgically as a palliative approach. In this study, we reviewed our experience with the surgical treatment of patients with cardiac metastases of various types of malignant tumors.

Methods Between 2003 and 2016, 10 patients underwent surgery for cardiac metastases at our institution.

Results The mean age was 53.5 ± 19 years. Female patients made up 60% (n = 6) of the collective. The cohort included cardiac metastases of diverse origins (peripheral sarcomas, melanoma, rectal carcinoma, and hepatocellular carcinoma). The left side of the heart was more frequently affected (n = 7). In only six patients, the primary malignancy was known at the time of cardiac surgery. The interval between the first diagnosis of the primary tumor and cardiac metastases ranged from simultaneous diagnosis to up to 19 years. At the time of the diagnosis of the cardiac metastases, seven patients already had multiple metastases: all seven patients had pulmonary metastases, and three of them additionally had hepatic, cerebral, or osseous metastases. Only four patients were symptomatic (atrial fibrillation, pericardial effusion, tachycardia with chest pain, dyspnea). There was no in-hospital death. The postoperative course was uneventful overall. The one- and two-year survival rates were similar, that is, 76%. The median follow-up time was 5.4 years.

Conclusions Surgical intervention for treating cardiac metastases is associated with uneventful clinical outcome and acceptable survival in this critically ill population. Control of the primary malignancy, and maybe other metastases, determines the survival.
V-band Doppler backscattering diagnostic in the TCV tokamak
Authors: Molina Cabrera P. , Coda S. , Porte L. , Offeddu N. , Lavanchy P. , Silva M. , Toussaint M. ,   TCV Team
Published: August 2018

A variable configuration V-band heterodyne Doppler back-scattering diagnostic has been recently made operational in the tokamak à configuration variable. This article describes the hardware setup options, flexible quasi-optical launcher antenna, data-analysis techniques, and first data. The diagnostic uses a fast arbitrary waveform generator as the main oscillator and commercial vector network analyzer extension modules as the main mm-wave hardware. It allows sweepable single or multi-frequency operation. A flexible quasi-optical launcher antenna allows 3D poloidal (10°–58°) and toroidal (−180° to 180°) steering of the beam with 0.2° accuracy. A pair of fast HE11 miter-bend polarizers allow flexible coupling to either O or X mode and programmable polarization changes during the shot. These have been used to measure the magnetic-field pitch angle in the edge of the plasma by monitoring the backscattered signal power. Ray-tracing simulations reveal an available k⊥ range between 3 and 16 cm−1 with a resolution of 2-4 cm−1. Perpendicular rotation velocity estimates compare well against ExB plasma poloidal rotation estimates from charge exchange recombination spectroscopy.
Influences of vacancy and doping on electronic and magnetic properties of monolayer SnS
Authors: Ullah Hamid , Noor-A-Alam Mohammad , Kim Hye Jung , Shin Young-Han
Published: August 2018

Based on the first-principles calculations, we investigate the structural, electronic, and magnetic properties of defects in monolayer SnS. We study the formation and migration of vacancies at both Sn- and S-sites. In comparison to the S-site vacancy, our calculations show that creating a vacancy at the Sn-site requires lesser energy, indicating that the vacancy at the Sn-site is more likely to be formed in experiments with energetic particle irradiation. For the Sn-rich (S-rich) environment, the vacancy at the S-site (Sn-site) is more likely to be found than the vacancy at the Sn-site (S-site). Reducing the formation of vacancy clusters, the S vacancy remains at the position where it is created because of the high vacancy migration barrier. Both types of vacancies remain nonmagnetic. To induce magnetism in monolayer SnS, we also study the transition metal (TM = Mn, Fe, and Co) doping at the Sn-site and find a significant influence on the electronic and magnetic properties of monolayer SnS. The doping of TM changes non-magnetic monolayer SnS to magnetic one and keeps it semiconducting. Additionally, long-range ferromagnetic behavior is observed for all the doped system. Hence, doping TM atoms in monolayer SnS could be promising to realize a two-dimensional diluted magnetic semiconductor. More interestingly, all the doped TM configurations show a high spin state, which can be used in nanoscale spintronic applications such as spin-filtering devices.
An efficient Bayesian kinetic lumping algorithm to identify metastable conformational states via Gibbs sampling
Authors: Wang Wei , Liang Tong , Sheong Fu Kit , Fan Xiaodan , Huang Xuhui
Published: August 2018

Markov State Model (MSM) has become a popular approach to study the conformational dynamics of complex biological systems in recent years. Built upon a large number of short molecular dynamics simulation trajectories, MSM is able to predict the long time scale dynamics of complex systems. However, to achieve Markovianity, an MSM often contains hundreds or thousands of states (microstates), hindering human interpretation of the underlying system mechanism. One way to reduce the number of states is to lump kinetically similar states together and thus coarse-grain the microstates into macrostates. In this work, we introduce a probabilistic lumping algorithm, the Gibbs lumping algorithm, to assign a probability to any given kinetic lumping using the Bayesian inference. In our algorithm, the transitions among kinetically distinct macrostates are modeled by Poisson processes, which will well reflect the separation of time scales in the underlying free energy landscape of biomolecules. Furthermore, to facilitate the search for the optimal kinetic lumping (i.e., the lumped model with the highest probability), a Gibbs sampling algorithm is introduced. To demonstrate the power of our new method, we apply it to three systems: a 2D potential, alanine dipeptide, and a WW protein domain. In comparison with six other popular lumping algorithms, we show that our method can persistently produce the lumped macrostate model with the highest probability as well as the largest metastability. We anticipate that our Gibbs lumping algorithm holds great promise to be widely applied to investigate conformational changes in biological macromolecules.
A solid-state refrigeration based on electrocaloric effect: Device and its analytical model
Authors: Sun Zhimin , Wang Qing-Ming , Slaughter William S.
Published: August 2018

A device concept of an electrocaloric solid-state refrigeration is presented in this paper. The core component of the device is flexural mode composite actuators, each of which is comprised of an electrocaloric layer and an elastic substrate layer bonded together. The composite actuators have an electric field induced temperature change due to the electrocaloric effect and also have large electric field induced flexural deformation due to the converse piezoelectric effect, which enables the device to bend to contact with the heat source (or heat sink) for transferring heat. An analytical model is derived by considering multi-physical couplings for an edge-clamped circular composite device, which can accurately predict the temperature change of the device as compared with the indirect approach derived from the Maxwell relation. The model shows that the temperature change is a combinatorial result from the couplings of thermal, electric, and mechanical field in the device. Moreover, the model sheds light on exploring the optimization of the solid-state refrigeration device and indicates that different thickness ratios and radius ratios of the composite actuators have a large influence on the cooling performance of the refrigerator.
Parametric study of thermal effects in a capillary dielectric-barrier discharge related to plasma jet production: Experiments and numerical modelling
Authors: Svarnas P. , Papadopoulos P. K. , Athanasopoulos D. , Sklias K. , Gazeli K. , Vafeas P.
Published: August 2018

In the present work, a capillary dielectric-barrier discharge of the coaxial electrode configuration, commonly employed to atmospheric-pressure cold plasma jet production, is studied in terms of thermal effects. The discharge is driven by sinusoidal high voltage in the kHz range and operates with helium gas channeled into a capillary dielectric tube having one end opened to the atmospheric air. The voltage amplitude and frequency, gas flow rate, and discharge volume are varied independently, and thermal effects are investigated by experimentally acquired results coupled with numerically determined data. The experiments refer to electrical power measurements, time-resolved temperature measurements, infrared imaging, and high resolution optical emission spectroscopy. The numerical modelling incorporates an electro-hydrodynamic force in the governing equations to take into account the helium-air interplay and uses conjugate heat transfer analysis. The comparison between experimental and numerical data shows that power is principally consumed in the dielectric barrier-helium interface resulting in the dielectric heating. A linear relation between steady state temperatures and supplied power, independent of the designing and operating conditions, is experimentally established. However, the gas flow rate affects the thermal effects differently compared to the other parameters, supporting the idea of a twofold nature of these systems, i.e., electrical and hydrodynamic. The main claim states the possibility of correlating (both experimentally and numerically) designing and operating parameters for evaluating heat distribution and gas temperature in capillary dielectric-barrier discharges used for plasma jet production. This is of high importance for processing temperature-sensitive materials, including bio-specimens.
A novel high thrust–weight ratio linear ultrasonic motor driven by single–phase signal
Authors: Fan Pingqing , Shu Xuecheng , Yuan Tao , Li Chaodong
Published: August 2018

This paper presents an ultrasonic motor with a high thrust–weight ratio. The miniaturized motor is 13 mm × 5 mm × 3.8 mm in size and uses the first-order bending vibration mode (B1 mode) and second-order bending vibration mode (B2 mode) to realize bidirectional movement through a single-phase driving signal. The theoretical trajectory and output thrust of the motor driving foot are initially studied. Subsequently, a finite-element model of the motor is established, and its dynamic performance is studied. Next, the prototype of the motor is fabricated and tested. The results show that errors in the B1 and B2 modes are 1.976% and 0.436%, respectively. Finally, an experimental setup is constructed to test the mechanical properties of the motor. The maximum output velocities of the motor is approximately 158 mm/s at 58.917 kHz in the B1 mode and approximately 137 mm/s at 113.581 kHz in the B2 mode. The maximum thrust force values of the motor in the B1 and B2 modes are approximately 1.32 N and 1.08 N, respectively, with 7 N preload and 120 Vpp voltage. The overall mass of the motor stator is 1.0 g, so the motor thrust–weight ratio reaches 134.69.
23% efficient p-type crystalline silicon solar cells with hole-selective passivating contacts based on physical vapor deposition of doped silicon films
Authors: Yan Di , Cuevas Andres , Phang Sieu Pheng , Wan Yimao , Macdonald Daniel
Published: August 2018

Of all the materials available to create carrier-selective passivating contacts for silicon solar cells, those based on thin films of doped silicon have permitted to achieve the highest levels of performance. The commonly used chemical vapour deposition methods use pyrophoric or toxic gases like silane, phosphine and diborane. In this letter, we propose a safer and simpler approach based on physical vapour deposition (PVD) of both the silicon and the dopant. An in-situ doped polycrystalline silicon film is formed, upon annealing, onto an ultrathin SiOx interlayer, thus providing selective conduction and surface passivation simultaneously. These properties are demonstrated here for the case of hole-selective passivating contacts, which present recombination current densities lower than 20 fA/cm2 and contact resistivities below 50 mΩ cm2. To further demonstrate the PVD approach, these contacts have been implemented in complete p-type silicon solar cells, together with a front phosphorus diffusion, achieving an open-circuit voltage of 701 mV and a conversion efficiency of 23.0%. These results show that PVD by sputtering is an attractive and reliable technology for fabricating high performance silicon solar cells.
Incoherent control of optical bistability and multistability in a hybrid system: Metallic nanoparticle-quantum dot nanostructure
Authors: Solookinejad G. , Jabbari M. , Nafar M. , Ahmadi E. , Asadpour S. H.
Published: August 2018

We discuss the optical bistability and multistability properties of incident light on a unidirectional ring cavity consisting of a hybrid semiconductor quantum dot-metal nanoparticle system driven by coupling and incoherent pumping fields. We consider the quantum dot system as a three-level V-type configuration which is placed near the metallic nanoparticle. We realize that the threshold of optical bistability and optical multistability can be controlled by tuning the center-to-center distance between quantum dots and metallic nanoparticles. Moreover, the effect of incoherent pumping field on optical bistability and optical multistability has been discussed for different distances between quantum dots and metallic nanoparticles.
Coupled-cluster based basis sets for valence correlation calculations. New primitives, frozen atomic natural orbitals, and basis sets from double to hextuple zeta for atoms H, He, and B–Ne
Authors: Claudino Daniel , Bartlett Rodney J.
Published: August 2018

A series of new basis sets generated from coupled-cluster theory are presented. Sets of primitive Gaussians for angular momentum shells containing occupied orbitals are optimized and extended until the Hartree-Fock energy improvement per electron falls below 10 μH. This same energy threshold is applied to the energy from the coupled-cluster singles, doubles, and perturbative triples (CCSD(T)) approximation and taken as a guide to the generation of sets of polarization functions, constructed at the level of second-order many-body perturbation theory, once it is shown that practically indistinguishable results are obtained if the more costly CCSD(T) approach is used. A variant of the usual atomic natural orbitals (ANOs) grounded on the frozen natural orbital idea is explored, leading to the frozen ANO (FANO) contraction scheme, whose truncation pattern and convergence capabilities are thoroughly tested. Due to its superior description of the single determinant solution, the FANOs are proposed as the recommended contraction approach. FANO basis sets of sizes ranging from double to hextuple zeta are provided for atoms H through Ne and examined in atomic and molecular calculations.
Effect of size and shape on the excitonic stimulated emission process in ZnO microstructures
Authors: Matsuzaki Ryosuke , Uchino Takashi
Published: August 2018

There has been some (partly controversial) discussion about the role of excitons in room-temperature laser emission of ZnO. Recently, we have demonstrated from temperature and excitation-density-dependent photoluminescence measurements on a ZnO film consisting of well crystallized micrometer-sized grains that the mechanism of optical gain at temperatures below ∼150 K is the exciton-exciton (ex-ex) scattering, whereas at temperatures from ∼150 K to room temperature, the gain results from the exciton-electron (ex-el) scattering without any contribution from electron-hole plasma lasing [R. Matsuzaki et al., Phys. Rev. B 96, 125306 (2017)]. However, the mechanism of optical feedback inside these ZnO microstructures is not fully understood. In this work, we investigate the emission properties of various ZnO microcrystals with different size and shape in the temperature region from 3 to 300 K using a nanosecond pulsed laser as an excitation source. We found that room temperature stimulated emission is observed only from the sphere-like ZnO particles with the size of a few micrometers in diameter. We also found the temperature-induced transition between ex-ex and ex-el scattering processes at a temperature of ∼150 K, similar to the case of the ZnO film consisting of micrometer-sized grains reported previously. The close similarity observed between the two different types of ZnO microstructures allows us to deduce that the temperature-dependent excitonic stimulated emission characteristics are common in micrometer-sized ZnO crystals with a low-loss feedback mechanism.
Extrinsic p-type doping of few layered WS2 films with niobium by pulsed laser deposition
Authors: Rathod Urmila P. , Egede Justin , Voevodin Andrey A. , Shepherd Nigel D.
Published: August 2018

Doping of few layered 2H WS2 films with Nb by pulsed laser deposition (PLD) using ablation targets fabricated from WS2, S and Nb powders is reported. The undoped controls were n-type, exhibited a Hall mobility of 0.4 cm2/Vs, and characterized by a Fermi level at 1.41 eV from the valence band edge. The latter was determined using ultraviolet photoelectron spectroscopy. Films doped at 0.5 and 1.1 atomic percentages niobium were p-type, and characterized by Fermi levels at 0.31 eV and 0.18 eV from the valence band edge. X-ray photoelectron spectroscopy indicates that Nb substitutes on W lattice sites. With increased Nb doping, the hole sheet concentration increased from 3.9 × 1012 to 8.6 × 1013 cm−2, while the mobility decreased from 7.2 to 2.6 cm2/Vs, presumably due to increased ionized impurity scattering. The approach demonstrates the potential of PLD for controlled doping of transition metal dichalcogenides.
Spin-selective electron transfer reactions of radical pairs: Beyond the Haberkorn master equation
Authors: Fay Thomas P. , Lindoy Lachlan P. , Manolopoulos David E.
Published: August 2018

Radical pair recombination reactions are normally described using a quantum mechanical master equation for the electronic and nuclear spin density operator. The electron spin state selective (singlet and triplet) recombination processes are described with a Haberkorn reaction term in this master equation. Here we consider a general spin state selective electron transfer reaction of a radical pair and use Nakajima-Zwanzig theory to derive the master equation for the spin density operator, thereby elucidating the relationship between non-adiabatic reaction rate theory and the Haberkorn reaction term. A second order perturbation theory treatment of the diabatic coupling naturally results in the Haberkorn master equation with an additional reactive scalar electron spin coupling term. This term has been neglected in previous spin chemistry calculations, but we show that it will often be quite significant. We also show that beyond the second order in perturbation theory, i.e., beyond the Fermi golden rule limit, an additional reactive singlet-triplet dephasing term appears in the master equation. A closed form expression for the reactive scalar electron spin coupling in terms of the Marcus theory parameters that determine the singlet and triplet recombination rates is presented. By performing simulations of radical pair reactions with the exact hierarchical equations of motion method, we demonstrate that our master equations provide a very accurate description of radical pairs undergoing spin-selective non-adiabatic electron transfer reactions. The existence of a reactive electron spin coupling may well have implications for biologically relevant radical pair reactions such as those which have been suggested to play a role in avian magnetoreception.
Extending the hierarchical quantum master equation approach to low temperatures and realistic band structures
Authors: Erpenbeck A. , Hertlein C. , Schinabeck C. , Thoss M.
Published: August 2018

The hierarchical quantum master equation (HQME) approach is an accurate method to describe quantum transport in interacting nanosystems. It generalizes perturbative master equation approaches by including higher-order contributions as well as non-Markovian memory and allows for the systematic convergence to the numerically exact result. As the HQME method relies on a decomposition of the bath correlation function in terms of exponentials, however, its application to systems at low temperatures coupled to baths with complexer band structures has been a challenge. In this publication, we outline an extension of the HQME approach, which uses re-summation over poles and can be applied to calculate transient currents at a numerical cost that is independent of temperature and band structure of the baths. We demonstrate the performance of the extended HQME approach for noninteracting tight-binding model systems of increasing complexity as well as for the spinless Anderson-Holstein model.
Non-destructive structural imaging of steelwork with atomic magnetometers
Authors: Bevington P. , Gartman R. , Chalupczak W. , Deans C. , Marmugi L. , Renzoni F.
Published: August 2018

We demonstrate the imaging of ferromagnetic carbon steel samples and we detect the thinning of their profile with a sensitivity of 0.1 mm using a Cs radio-frequency atomic magnetometer. Images are obtained at room temperature, in magnetically unscreened environments. By using a dedicated arrangement of the setup and active compensation of background fields, the magnetic disturbance created by the samples' magnetization is compensated. Proof-of-concept demonstrations of non-destructive structural evaluation in the presence of concealing conductive barriers are also provided. The relevant impact for steelwork inspection and health and usage monitoring without disruption of operation is envisaged, with direct benefit for industry, from welding in construction to pipeline inspection and corrosion under insulation in the energy sector.
Low dissipation spectral filtering using a field-effect tunable III–V hybrid metasurface
Authors: Sarma Raktim , Campione Salvatore , Goldflam Michael , Shank Joshua , Noh Jinhyun , Smith Sean , Ye Peide D. , Sinclair Michael , Klem John , Wendt Joel , Ruiz Isaac , Howell Stephen W. , Brener Igal
Published: August 2018

Considering the power constrained scaling of silicon complementary metal-oxide-semiconductor technology, the use of high mobility III–V compound semiconductors such as In0.53Ga0.47As in conjunction with high-κ dielectrics is becoming a promising option for future n-type metal-oxide-semiconductor field-effect-transistors. Development of low dissipation field-effect tunable III–V based photonic devices integrated with high-κ dielectrics is therefore very appealing from a technological perspective. In this work, we present an experimental realization of a monolithically integrable, field-effect-tunable, III–V hybrid metasurface operating at long-wave-infrared spectral bands. Our device relies on strong light-matter coupling between epsilon-near-zero (ENZ) modes of an ultra-thin In0.53Ga0.47As layer and the dipole resonances of a complementary plasmonic metasurface. The tuning mechanism of our device is based on field-effect modulation, where we modulate the coupling between the ENZ mode and the metasurface by modifying the carrier density in the ENZ layer using an external bias voltage. Modulating the bias voltage between ±2 V, we deplete and accumulate carriers in the ENZ layer, which result in spectrally tuning the eigenfrequency of the upper polariton branch at 13 μm by 480 nm and modulating the reflectance by 15%, all with leakage current densities less than 1 μA/cm2. Our wavelength scalable approach demonstrates the possibility of designing on-chip voltage-tunable filters compatible with III–V based focal plane arrays at mid- and long-wave-infrared wavelengths.
Effect of body condition and melatonin implants, inserted at different times of the year, on ovarian activity in goats maintained without male contact from the time of implantation
Authors: Gallego-Calvo María de Lourdes , Gatica María Carolina , Guzmán José Luis , Zarazaga Luis A.
Published: August 2018

The aim of the present work was to asses (1) whether body condition (BC) and (2) melatonin implants, inserted at different times of the year between the winter and summer solstices, have an effect on seasonal ovulatory activity in goats without presence of males. Sixty-six Blanca Andaluza does were divided into six groups. Five of these received a melatonin implant on either 18 December (n = 10), 3 February (n = 12), 19 March (n = 12), 30 April (n = 11) or 11 June (n = 11). Following this procedure, the does were completely isolated from bucks. Another 10 goats (YEAR group) were used to monitor natural annual ovarian activity; these females were completely isolated from males over the entire experimental period (from 18 December of one year until 17 December of the next year). Half the does of each group had a low body condition score (BC; ≤2.50; 2.46 ± 0.02), and half had a high BC (≥3.00; 3.24 ± 0.04). Ovulatory activity was monitored via the progesterone concentrations determined in blood samples collected twice per week for 4 months following melatonin implantation, and over 12 months for the YEAR group. Over 46% of the females showed ovarian activity after the melatonin treatment, ranging from the lowest response in December (30%) and the highest one in February (75%) without differences between the dates of melatonin insertion (P > 0.05). However, the response to the melatonin implant was higher in the females with a high BC than in females with a low BC (63% vs 31% for high and of low BC respectively, P < 0.05). The present results indicated that melatonin implants induce ovarian activity in does in the absence of male contact. The moment of melatonin implantation did not modify ovulatory activity. However, the ovulatory response to melatonin implants was higher in the females with a BC of ≥3.00.