bluuebunny/crossref_metadata_2025 huggingface dataset:
H19 and Foxc2 synergistically promotes osteogenic differentiation of BMSCs via Wnt‐β‐catenin pathway
Authors: Zhou Ping , Li Ying , Di Ruolin , Yang Yi , Meng Songyan , Song Fangfang , Ma Lan
Published: January 2019

Objective

To investigate the mechanism of H19 on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs).

Methods

Ovariectomized (OVX) mouse model was established. RNA immunoprecipitation and RNA pull‐down assays were performed to determine the correlation between H19 and forkhead box C2 (Foxc2). Chromatin immunoprecipitation assay was used to identify whether Foxc2 binds to the Wnt4 promoter region. Molecules expressions were measured by quantitative real‐time polymerase chain reaction and western blot.

Results

We found that H19 expression was reduced in the serum of patients with postmenopausal osteoporosis and BMSCs of OVX mice, and overexpression of H19 promoted osteogenic differentiation of BMSCs. Additionally, Foxc2 could bind to the Wnt4 promoter and promote its transcription. We also showed that H19 could bind to Foxc2, and H19/Foxc2 regulated Wnt promoter expression in a synergistic fashion, and H19/Foxc2 regulated osteogenic differentiation of BMSCs through Wnt‐β‐catenin pathway.

Conclusion

H19 and Foxc2 synergistically promoted osteogenic differentiation of BMSCs via Wnt‐β‐catenin pathway.
miR‐210 promotes lung adenocarcinoma proliferation, migration, and invasion by targeting lysyl oxidase‐like 4
Authors: Xie Songping , Liu Gaoli , Huang Jie , Hu Hai‐Bo , Jiang Wanli
Published: January 2019

Accumulating evidence has revealed that various microRNAs are deregulated and involved in lung cancer development and metastasis. miR‐210 is implicated in several cancer progression. However, the detailed biological function and role of miR‐210 in lung adenocarcinoma remains unclear. Our current study was aimed to investigate the mechanism of miR‐210 in lung adenocarcinoma progression. We observed that miR‐210 was significantly upregulated in lung cancer cell lines (A549 and H1650) in comparison to BEAS‐2B cells. In addition, we found that miR‐210 was greatly elevated in lung adenocarcinoma tissues. Then, it was shown that overexpression of miR‐210 was able to promote lung cancer cell proliferation and colony formation ability while inhibitors of miR‐210 exhibited a reversed phenomenon. Subsequently, A549 and H1650 cell migration and invasion capacity were obviously restrained by miR‐210 inhibition whereas induced by miR‐210 mimics. Lysyl oxidase‐like 4 (LOXL4), a member of the secreted copper‐dependent amine oxidases has been found to be increased or decreased in different cancer types. Here, we confirmed that LOXL4 could serve as a downstream target of miR‐210 and miR‐210 promoted lung cancer progression via targeting LOXL4. In A549 and H1650 cells, knockdown of LOXL4 dramatically repressed lung cancer cell proliferation, migration, and invasion. In conclusion, our study implied that miR‐210 might indicate a new perspective for lung cancer.
RETRACTED: PNU‐74654 enhances the antiproliferative effects of 5‐FU in breast cancer and antagonizes thrombin‐induced cell growth via the Wnt pathway
Authors: Rahmani Farzad , Amerizadeh Forouzan , Hassanian Seyed Mahdi , Hashemzehi Milad , Nasiri Seyedeh‐Najibeh , Fiuji Hamid , Ferns Gordon A. , Khazaei Majid , Avan Amir
Published: January 2019

The Wnt/β‐catenin pathway is one of the most common pathways dysregulated in breast cancer, and may, therefore, be a potential‐therapeutic target. We have investigated the effects of PNU‐74654 in breast cancer, as a Wnt/β‐catenin inhibitor, either alone or in combination with fluorouracil (5‐FU). PNU‐74654 suppressed cell growth at an IC
50 of 122 ± 0.4 μmol/L and synergistically enhanced the antiproliferative activity of gemcitabine by modulating the Wnt pathway. Using a 3D cell culture model, we found that the PNU‐74654 caused tumor shrinkage. It reduced the migration of MCF‐7 cells (by an 18% reduction in invasive behavior) after the treatment with PNU‐74654 through perturbation of E‐cadherin and MMP3/9. PNU‐74654/5‐FU combination enhanced the percentages of cells in S‐phase and significantly increased apoptosis. Moreover, our data showed that this agent was able to inhibit the growth of tumor in a xenograft model, although this effect was more pronounced in the animals treated with PNU‐74654 plus 5‐FU. These data show the ability of PNU‐74654 to specifically target Wnt pathway, interfere with cell proliferation, induce‐apoptosis, reduce‐migration, and synergistically interact with 5‐FU, supporting further studies on this novel therapeutic‐approach for breast cancer.
Use of Physiologically Based Pharmacokinetic Modeling to Identify Physiological and Molecular Characteristics Driving Variability in Axitinib Exposure: A Fresh Approach to Precision Dosing in Oncology
Authors: Sorich Michael J. , Mutlib Fayzah , van Dyk Madelé , Hopkins Ashley M. , Polasek Thomas M. , Marshall Jean‐Claude , Rodrigues A. David , Rowland Andrew
Published: January 2019

Axitinib is a second‐generation small‐molecule vascular endothelial growth factor receptor inhibitor. An axitinib steady‐state area under the plasma concentration–time curve (AUCSS) >300 ng/mL/hr is associated with superior progression‐free and overall survival. This study sought to characterize the physiological and molecular characteristics driving variability in axitinib AUCSS using physiologically based pharmacokinetic modeling to identify exposure biomarkers for this drug. The capacity to predict subjects likely to fail to achieve an axitinib AUCSS >300 ng/mL/hr was evaluated as a secondary outcome. A full physiologically based pharmacokinetic model incorporating mechanistic absorption was developed and verified for axitinib in accordance with the US Food and Drug Administration Guidance using Simcyp (Version 17.1). This model was used to simulate axitinib exposure over 7 days with twice‐daily dosing (5 mg) in a cohort of 1000 virtual cancer patients. Multiple linear regression modeling was used to identify patient characteristics associated with differences in axitinib exposure. A multivariable linear regression model incorporating hepatic cytochrome P450 (CYP) 3A4 abundance, albumin concentration, hepatic CYP1A2 abundance, hepatic CYP2C19 abundance, and intestinal CYP2C19 abundance provided robust prediction of axitinib AUCSS (R2 = 0.890; P < .001). By accounting for these variables, it was possible to identify subjects who would fail to achieve an effective axitinib AUCSS with a specificity of 88.7% and a sensitivity of 92.6%. Variability in axitinib AUCSS is primarily driven by differences in hepatic CYP3A4 abundance and albumin concentration. Consideration of these 2 characteristic is likely to be sufficient to individualize axitinib dosing.
Brain aging: A Ianus‐faced player between health and neurodegeneration
Authors: Vanni Silvia , Colini Baldeschi Arianna , Zattoni Marco , Legname Giuseppe
Published: January 2019

Neurodegenerative diseases are incurable debilitating disorders characterized by structural and functional neuronal loss. Approximately 30 million people are affected worldwide, and this number is predicted to reach more than 150 million by 2050. Neurodegenerative disorders include Alzheimer’s, Parkinson’s, and prion diseases among others. These disorders are characterized by the accumulation of aggregating proteins forming amyloid, responsible for the disease‐associated pathological lesions. The aggregation of amyloidogenic proteins can result either in gaining of toxic functions, derived from the damage provoked by these deposits in affected tissue, or in a loss of functions, due to the sequestration and the consequent inability of the aggregating protein to ensure its physiological role. While it is widely accepted that aging represents the main risk factor for neurodegeneration, there is still no clear cut‐off line between the two conditions. Indeed, many of the pathways that are commonly altered in neurodegeneration—misfolded protein accumulation, chronic inflammation, mitochondrial dysfunction, impaired iron homeostasis, epigenetic modifications—have been often correlated also with healthy aging. This overlap could be explained by the fact that the continuous accumulation of cellular damages, together with a progressive decline in metabolic efficiency during aging, makes the neurons more vulnerable to toxic injuries. When a given threshold is exceeded, all these alterations might give rise to pathological phenotypes that ultimately lead to neurodegeneration.
A pollen–climate calibration from western Patagonia for palaeoclimatic reconstructions
Authors: Montade Vincent , Peyron Odile , Favier Charly , Francois Jean Pierre , Haberle Simon G.
Published: January 2019

Palaeoecological studies of sediment records from the western margins of southern South America have revealed vegetation dynamics to be under the influence of major regional climate drivers such as the Southern Westerly Winds, Southern Annular Mode and El Niño Southern Oscillation. Despite the substantial number of palynological records in this region, very few quantitative pollen‐based climate reconstructions using surface samples have been made. In this context, our objective was first to investigate the modern pollen–vegetation–climate relationships in the western Patagonian. The results show that the modern pollen dataset reflects the main vegetation types and that summer precipitation and winter temperature represent the main climate parameters controlling vegetation distribution. Secondly using this pollen–climate dataset we evaluate and compare the performance of two models (Weighted Averaging Partial Least Squares and Modern Analog Technique). We used these models to make climate reconstructions from two oceanic pollen records from western Patagonia. Compared with independent climate indicators, our pollen‐inferred climate reconstructions reveal the same overall trends, showing the potential of pollen–climate transfer functions applied to this region. This study provides much needed data for quantitative climate reconstructions in South America, but which also needs to be improved by enlarging the modern pollen dataset.
Infrared sensors using poly‐Si thin‐film transistors for proximity sensors integrated in smartphone displays
Authors: Kito Katsuya , Kitajima Shuhei , Matsuda Tokiyoshi , Inoue Masahide , Tamura Mitsuo , Kimura Mutsumi
Published: January 2019

We have developed infrared sensors using poly‐Si thin‐film transistors (TFTs) for proximity sensors integrated in smartphone displays. Initially, we evaluate the infrared sensitivities of the poly‐Si TFTs, and it is found that a pin‐type TFT is suitable for the infrared sensors. Next, we propose three types of the infrared sensors. First, an analog current detection‐type sensor has a simple structure, and it is found that it can detect presence of a hand. Second, a lock‐in detection‐type sensor has tolerance against ambient light, and it is found that it can detect a target signal under noise signals. Third, a frequency detection‐type sensor has an advantage that only a digital circuit is necessary for detection, and it is found that it can detect the infrared intensity because the oscillation frequency increases monotonically with the intensity. We can utilize these infrared sensors on demand.
Laryngeal mask versus intubation for adenoidectomies in children: Analysis of 1,500 operations
Authors: Gehrke Thomas , Hackenberg Stephan , Steinhübel Bernhard , Hagen Rudolf , Scherzad Agmal
Published: January 2019

Objectives/Hypothesis

To evaluate whether endotracheal intubations are superior to the use of laryngeal masks in the airway management for adenoidectomies in pediatric patients in terms of safety and duration of surgery.

Study Design

Retrospective case series.

Methods

A retrospective analysis of 1,500 adenoidectomies in children using laryngeal mask or endotracheal intubation for intraoperative ventilation between 2009 and 2017. Data collected included complications, duration of surgery, and duration of induction and emergence from anesthesia.

Results

The use of laryngeal masks did not accelerate the time needed for induction and emergence of anesthesia although significantly increasing the duration of surgery itself. There also were significantly more complications during and after anesthesia when using a laryngeal mask. In 10% of the children, the laryngeal mask had to be replaced by an endotracheal tube intraoperatively.

Conclusions

There is no reason to recommend the use of a laryngeal mask as the first choice of airway management regarding adenoidectomies in children.

Level of Evidence

3 Laryngoscope, 129:E383–E388, 2019
Semi‐Nonlinear Nanophotonic Waveguides for Highly Efficient Second‐Harmonic Generation
Authors: Luo Rui , He Yang , Liang Hanxiao , Li Mingxiao , Lin Qiang
Published: January 2019

Quadratic optical parametric processes form the foundation for various applications related to classical and quantum frequency conversion, and have attracted significant interest recently in on‐chip implementation. These processes rely on phase matching among the interacting guided modes, and refractive index engineering is a primary approach for this purpose. Unfortunately, modal phase‐matching approaches developed so far only produce parametric generation with fairly low efficiencies, due to the intrinsic modal mismatch of spatial symmetries. Here, a universal design and operation principle is proposed for highly efficient optical parametric generation on integrated photonic platforms. By breaking the spatial symmetry of the optical nonlinearity of the device, nonlinear parametric interactions can be dramatically enhanced. This principle is then employed to design and fabricate a heterogeneous titanium oxide/lithium niobate nanophotonic waveguide that is able to offer second‐harmonic generation with a theoretical normalized conversion efficiency as high as 2900, which enables the measurement of an experimental efficiency of 650, significantly beyond the reach of conventional modal phase‐matching approaches. Unlike nonlinearity domain engineering that is material selective, the proposed operation principle can be flexibly applied to any other on‐chip quadratic nonlinear platform, to support ultra‐highly efficient optical parametric generation.
Increased Dynamin‐Related Protein 1–Dependent Mitochondrial Fission Contributes to High‐Fat‐Diet‐Induced Cardiac Dysfunction and Insulin Resistance by Elevating Tafazzin in Mouse Hearts
Authors: Chang Wenguang , Xiao Dandan , Ao Xiang , Li Mengyang , Xu Tao , Wang Jianxun
Published: January 2019

Scope

High fat (HF)‐diet‐induced insulin resistance is a major contributor to the pathogenesis of cardiovascular diseases. However, the molecular mechanisms that regulate cardiac insulin signaling are not fully understood. The regulatory role of tafazzin in the hearts of HF‐diet‐fed mice is investigated.

Methods and results

Mice are fed a HF diet or low fat (LF) diet for up to 24 weeks. After 24 weeks, it is found that HF‐diet‐induced cardiac dysfunction is linked to overexpression of the mitochondrial protein tafazzin. Increased tafazzin promotes mitochondrial fission and impairs insulin signaling, which is mediated by dynamin‐related protein 1 (Drp‐1) translocation from the cytosol to the mitochondria. Furthermore, knockdown of tafazzin with siRNA inhibits palmitic‐acid–induced mitochondrial fission and restores insulin sensitivity. Moreover, miR‐125b‐5p as an upstream regulator targeting tafazzin is identified and palmitate‐induced insulin resistance further rescued.

Conclusion

In HF‐diet‐fed mouse hearts, increased tafazzin contributes to insulin resistance via mediating Drp‐1 translocation to the mitochondria, and a small non‐coding RNA, miR‐125b‐5p, at least partially regulates this signaling pathway and alleviates insulin resistance.
Cancer metabolism in a snapshot: MRS(I)
Authors: Julià‐Sapé Margarida , Candiota Ana Paula , Arús Carles
Published: January 2019

The contribution of MRS(I) to the in vivo evaluation of cancer‐metabolism‐derived metrics, mostly since 2016, is reviewed here. Increased carbon consumption by tumour cells, which are highly glycolytic, is now being sampled by 13C magnetic resonance spectroscopic imaging (MRSI) following the injection of hyperpolarized [1‐13C] pyruvate (Pyr). Hot‐spots of, mostly, increased lactate dehydrogenase activity or flow between Pyr and lactate (Lac) have been seen with cancer progression in prostate (preclinical and in humans), brain and pancreas (both preclinical) tumours. Therapy response is usually signalled by decreased Lac/Pyr 13C‐labelled ratio with respect to untreated or non‐responding tumour. For therapeutic agents inducing tumour hypoxia, the 13C‐labelled Lac/bicarbonate ratio may be a better metric than the Lac/Pyr ratio. 31P MRSI may sample intracellular pH changes from brain tumours (acidification upon antiangiogenic treatment, basification at fast proliferation and relapse). The steady state tumour metabolome pattern is still in use for cancer evaluation. Metrics used for this range from quantification of single oncometabolites (such as 2‐hydroxyglutarate in mutant IDH1 glial brain tumours) to selected metabolite ratios (such as total choline to N‐acetylaspartate (plain ratio or CNI index)) or the whole 1H MRSI(I) pattern through pattern recognition analysis. These approaches have been applied to address different questions such as tumour subtype definition, following/predicting the response to therapy or defining better resection or radiosurgery limits.
Stress distributions in nanocomposite sandwich cylinders reinforced by aggregated carbon nanotube
Authors: Shokri‐Oojghaz Reza , Moradi‐Dastjerdi Rasool , Mohammadi Hassan , Behdinan Kamran
Published: January 2019

In order to improve the static response of thick hollow cylinders, a sandwich cylinder with two carbon nanotube (CNT)‐reinforced nanocomposite face sheets are proposed in this article. Moreover, due to the use of optimum amount of high cost CNTs, the CNT distribution is suggested to be functionally graded (FG) along the thickness of cylinder. The stress and deflection profiles of the proposed sandwich cylinders subjected to internal and external pressures have been investigated using a finite element method (FEM) based on an axisymmetric model. The significant effect of formation of CNT agglomerations in the surrounded matrix is considered and the material properties of the resulted nanocomposite are estimated by Eshelby‐Mori‐Tanaka approach. Using the developed axisymmetric FEM model, the effects of CNT aggregation state, volume fraction, and distribution as well as geometrical dimension and loading condition on the stress and deflection distributions of the nanocomposite sandwich cylinders have been characterized. The extensive simulations have revealed that instead of adding higher volume fraction of CNT, the selection of suitable distribution for CNTs can lead to a nanocomposite sandwich cylinder with less deflection. POLYM. COMPOS., 40:E1918–E1927, 2019. © 2019 Society of Plastics Engineers
Tribological behavior of polymer composites containing microcapsules and fibrous fillers: Finite element analysis and experimental verification
Authors: Su Chang , Wang Huaiyuan , Li Meiling , Ma Yingjie , Zhu Yanji
Published: January 2019

In allusion to the repeatability and complexity of tribological experiments, numerical simulations were carried out successfully to study the effect of microcapsules (MCs) and carbon fibers (CFs) contents on the longitudinal frictional temperature and Von Mises stress transfers of composites. Novel MC‐(fibrous filler) finite element (FE) models for polyvinylidene fluoride (PVDF) composites were established by observing morphologies of truncation surface, thermogravimetric analyzer (TGA) test and mathematical calculation. The thermal‐stress coupled analysis revealed the influence of oily microcapsules (OMCs) and CFs on thermal conductivity, thermal expansion, and elastic modulus of composites had further transformed the tribological properties of polymer composites. Moreover, tribological tests were carried out scientifically to verify the high accuracy of the simulated results with the error <8%. Both the experiment and simulation results indicated that 20 wt% OMCs/8 wt% CFs/PVDF composites possessed the optimal tribological properties. These demonstrate the novel FE models can predict the tribological properties of polymer composites containing MCs and fibrous fillers legitimately. POLYM. COMPOS., 40:3453–3463, 2019. © 2019 Society of Plastics Engineers
Redox Proteomic Analysis Reveals Oxidative Modifications of Proteins by Increased Levels of Intracellular Reactive Oxygen Species during Hypoxia Adaptation of Aspergillus fumigatus
Authors: Shekhova Elena , Ivanova Lia , Krüger Thomas , Stroe Maria C. , Macheleidt Juliane , Kniemeyer Olaf , Brakhage Axel A.
Published: January 2019

Aspergillus fumigatus faces abrupt changes in oxygen concentrations at the site of infection. An increasing number of studies has demonstrated that elevated production of intracellular reactive oxygen species (ROS) under low oxygen conditions plays a regulatory role in modulating cellular responses for adaptation to hypoxia. To learn more about this process in A. fumigatus, intracellular ROS production during hypoxia has been determined. The results confirm increased amounts of intracellular ROS in A. fumigatus exposed to decreased oxygen levels. Moreover, nuclear accumulation of the major oxidative stress regulator AfYap1 is observed after low oxygen cultivation. For further analysis, iodoTMT labeling of redox‐sensitive cysteine residues is applied to identify proteins that are reversibly oxidized. This analysis reveals that proteins with important roles in maintaining redox balance and protein folding, such as the thioredoxin Asp f 29 and the disulfide‐isomerase PdiA, undergo substantial thiol modification under hypoxia. The data also show that the mitochondrial respiratory complex IV assembly protein Coa6 is significantly oxidized by hypoxic ROS. Deletion of the corresponding gene results in a complete absence of hypoxic growth, indicating the importance of complex IV during adaptation of A. fumigatus to oxygen‐limiting conditions.
Automated control of inspired oxygen (FiO2) in preterm infants: Literature review
Authors: Dani Carlo
Published: January 2019

The vast majority (95%) of very preterm infants receive oxygen‐therapy monitored by oxygen pulse saturation (SpO2). However, they spend a significant percentage of time out of the SpO2 target with a high risk of severe complications such as bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP). Recently, systems allowing the automated control of inspired oxygen (FiO2) for patient delivery to maintain target SpO2 has been become commercially available. We reviewed literature and individuated sixteen studies on the effectiveness of automated control of FiO2 in preterm infants. These studies demonstrate that automated devices are significantly more effective than manual control in maintaining target SpO2 and in preventing hyperoxia, while they seem to be less effective in preventing hypoxia. The studies were very heterogeneous for design, population size, duration, and device used, and this precludes firm conclusions regarding effectiveness and best setting of these systems. Moreover, none of the studies investigated if automated control of FiO2 can actually improve outcome in preterm infants. We conclude that further large‐scale studies are warranted to assess the actual clinical relevance of these devices and to decide if they should become the standard of care.
Shock Initiation of Nano‐TATB Explosives under Short‐Duration Pulses
Authors: Guo Xiangli , Wang Jun , Ran Jianlong , Zhao Lulu , Han Yong , Cao Wei
Published: January 2019

Because of the potential of nano‐TATB as a charge in slapper detonator, the shock initiation threshold of nano‐TATB explosive was studied over short pulse durations (down to 0.017 μs) and high pressure ranges (up to 17 GPa). The pulses were produced by the impact of thin plastic flyer plates, which were accelerated by electrically exploded metal foils. Nano‐TATB powders with a mean particle size of 60 nm were prepared and pressed into cylindrical sample charges with three densities (1.56, 1.64 and 1.74 g/cm3). The flyer impact velocity data versus charging voltages was measured with different flyer thicknesses. Together with the Hugoniot relationships of flyer and samples, the impact pressures and pulse durations were calculated. By using Langlie method, the threshold pressures for shock initiation were determined. In case of the identical flyer plate, the threshold pressure increases with increasing density. In case of the identical explosive density, the threshold pressure increases as the thickness of the flyer decreases (i. e. the pulse duration decreases) except for the highest tested density. These data are represented well by a constant P2τ initiation criterion for the short, high‐pressure pulses and deviate from the P2τ behavior at lower pressures. Finally, nano‐TATB is proved to be a little more sensitive to short‐duration pulses than superfine TATB, but much more sensitive than production grade TATB.
Formation of Inverted Pyramid‐Like Submicron Structures on Multicrystalline Silicon Using Nitric Acid as Oxidant in Metal Assisted Chemical Etching Process
Authors: Yang Wangyang , Shen Honglie , Jiang Ye , Tang Quntao , Raza Adil , Gao Kai
Published: January 2019

H2O2 is predominantly used as an oxidizer in traditional metal assisted chemical etching (MACE), showing a high consumption rate due to its instability at room temperature. In this work, low concentration HNO3 instead of H2O2 is investigated in Ag‐assisted chemical etching process for multicrystalline silicon (mc‐Si) wafer. In comparative experiments, black silicon wafers with a surface reflection of 6.46% are obtained using HNO3 with only 5% molar concentration quantity of H2O2. After a post nanostructure rebuilding treatment, nano‐scale inverted pyramid‐like structures are obtained. SEM images reveal that increase in HNO3 concentration lead to an increase in surface roughness with enlarged structure size. Furthermore, a linear increase in etching rate is observed when AgNO3 concentration raised from 0 to 0.8 × 10−3m. The activation energy of 95.4 eV for the HNO3/HF‐Si reaction catalyzed by Ag is obtained by Arrhenius equation. The outcomes demonstrate HNO3 as a potential alternative to conventional oxidizer H2O2 in traditional MACE process.
HRTEM Study of Size‐Controlled Bi Quantum Dots in Annealed GaAsBi/AlAs Multiple Quantum Well Structure
Authors: Skapas Martynas , Stanionytė Sandra , Paulauskas Tadas , Butkutė Renata
Published: January 2019

High‐resolution transmission electron microscopy (HRTEM) study of statistically large number of Bi quantum dots (QD) in annealed GaAsBi/AlAs multiple quantum well (MQW) structures is presented in this work. Superlattices containing 20 alternating periods of 10 nm thick GaAsBi quantum well and AlAs 20 nm thick barrier layers are grown on semi‐insulating GaAs at 330 °C temperature. Dispersed Bi quantum dots are formed within the bismide layers during a post‐growth annealing at 750 °C. Energy dispersive X‐ray (EDX) mapping and high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM) analysis reveal that GaAsBi phase is altered during the annealing treatment forming a partially Bi‐depleted GaAsBi phase and semiconducting Bi nanoparticles. AlAs layers are found to act as barriers for Bi out‐diffusion, thus controlling the size of the QDs. The analysis of HRTEM micrographs confirms that Bi quantum dots consist of a rhombohedral Bi phase randomly distributed within zinc blende GaAsBi layers. Geometric phase analysis (GPA) also shows that GaAsBi layers are strained with respect to AlAs layers, as supported by the high‐resolution X‐ray diffraction (HRXRD) data. These findings demonstrate a highly controlled synthesis of Bi‐based quantum dots and pave the way for future applications in the field of infrared devices.
Photoluminescence from InAs Quantum Dots Buried Under Low‐Temperature‐Grown GaAs
Authors: Kosarev Alexander , Bert Nikolay , Nevedomskii Vladimir , Chaldyshev Vladimir , Preobrazhenskii Valerii , Putyato Mikhail , Semyagin Boris
Published: January 2019

Optical and structural study of a system of InAs quantum dots (QDs) buried under low‐temperature (LT) grown GaAs layers with different buffer layers in between has been performed. It has been shown that the buffer is very important for both atomic structure and electronic processes. The direct overgrowth at low temperature causes the formation of misfit dislocation and related drop of the photoluminescence (PL) intensity from the InAs QDs. The defect formation is eliminated by using either 5 nm thick GaAs or combined AlAs/GaAs buffer. Strong changes in the QD‐related PL intensity and line shape are experimentally revealed in the case of thin GaAs buffer. These changes are quantitatively described in terms of electron tunneling from the InAs QDs through the GaAs barrier to the continuum of states in the LT‐GaAs. When a 2.5 nm thick portion of the GaAs buffer is substituted by AlAs, the barrier becomes nontransparent for the electron tunneling from the ground states in the InAs QDs. As a result, the QD‐related PL becomes much stronger and the line shape becomes similar to that from the reference sample in the photon energy range of ground state transitions.
Effects of Spatial Dispersion in Symmetric and Asymmetric Semiconductor Quantum Wells
Authors: Kotova Lyubov V. , Platonov Alexei V. , Kats Vladimir N. , Sorokin Sergey V. , Ivanov Sergey V. , André Regis , Bugrov Vladislav E. , Kochereshko Vladimir P.
Published: January 2019

Effects of spatial dispersion in quantum wells are discovered and investigated in detail in reflection experiments. We studied oblique incidence of pure s and p polarized light which has been reflected elliptically polarized. The polarization degree of the reflected light is governed by the in‐plane photon momentum which is the distinctive feature of the spatial dispersion effects. The effects of spatial dispersion are allowed by symmetry in inversion‐asymmetric systems only. Therefore we investigated bulk‐inversion asymmetric ZnSe/ZnMgSSe and structure‐asymmetric GaAs/AlGaAs and CdZnTe/CdTe/CdMgTe quantum wells. We studied the reflected light polarization state in the vicinity of the heavy‐ and light‐exciton resonances where the spatial dispersion effects are resonantly enhanced.
Time‐Dependent Electrical Transport Properties of Topological Insulator Cr‐Doped Bi2Se3 Thin Films
Authors: Li Qiu Lin , Zhang Xing Hua , Wang Wen Jie , Li Zhi Qing , Zhou Ding Bang , Gao Kuang Hong
Published: January 2019

This paper reports the research of the electrical transport properties of Cr‐doped Bi2Se3 thin films. The films with a uniform Cr distribution exhibit the same structure as undoped Bi2Se3 thin film. At low temperatures, both the weak antilocalization (WAL) and the electron–electron interaction (EEI) effects are observed. From the WAL effect, the dephasing length and the number of the transport channels are extracted. The temperature dependence of the extracted dephasing length can be described by both the Nyquist electron–electron and the electron–phonon scatterings. With increasing time in vacuum, the resistances of the thin films exhibit a transition from the negative to the positive temperature coefficient, with an increase in electron density. Unexpectedly, the number of the transport channels extracted from the WAL effect is found to increase with increasing time, which is further confirmed by analyzing the EEI effect. This observation can be attributed to the presence of two‐dimensional electron gas on the surface of films, which is likely to be formed through the surface reaction with water.
Anticancer properties of erucin, an H2S‐releasing isothiocyanate, on human pancreatic adenocarcinoma cells (AsPC‐1)
Authors: Citi Valentina , Piragine Eugenia , Pagnotta Eleonora , Ugolini Luisa , Di Cesare Mannelli Lorenzo , Testai Lara , Ghelardini Carla , Lazzeri Luca , Calderone Vincenzo , Martelli Alma
Published: January 2019

Plants of the Brassicaceae family are well‐known for containing the glucosinolate myrosinase system, which is able to release isothiocyanates after plant biotic and abiotic lesions. Erucin (ERU; 1‐isothiocyanato‐4‐(methylthio)‐butane), an isothiocyanate particularly abundant in arugula (Eruca sativa Mill., Eruca vesicaria L., etc.), derives from the hydrolysis of the glucosinolate glucoerucin by the enzyme myrosinase. Many other natural isothiocyanates influence cancer cells and, in particular, induce antiproliferative effects at relatively high concentrations. Similar antiproliferative effects have also been shown by the newly emerging gasotransmitter hydrogen sulfide (H2S) and by H2S‐releasing compounds. In a previous study, our group demonstrated that isothiocyanates release H2S in biological environments. In this work, we demonstrated the H2S‐donor properties of ERU in pancreatic adenocarcinoma cells (AsPC‐1) and delineated its profile as a chemopreventive or anticancer agent. Indeed, ERU showed significant antiproliferative effects: ERU inhibited AsPC‐1 cell viability at relatively high concentrations (30–100 μM). Moreover, ERU inhibited cell migration, altered the AsPC‐1 cell cycle, and exhibited proapoptotic effects. Finally, ERU inhibited ERK1/2 phosphorylation. This mechanism is particularly important in AsPC‐1 cells because they are characterized by a mutation in KRAS that determines KRAS hyperactivation followed by MAP‐kinase hyperphosphorylation, which plays a pivotal role in pancreatic cancer proliferation, growth, and survival.
Metabolic effect of berberine–silymarin association: A meta‐analysis of randomized, double‐blind, placebo‐controlled clinical trials
Authors: Fogacci Federica , Grassi Davide , Rizzo Manfredi , Cicero Arrigo F.G.
Published: January 2019

The aim of this study is to assess the impact of a combination of berberine and silymarin on serum lipids and fasting plasma glucose (FPG) through a systematic review of literature and meta‐analysis of the available randomized, double‐blind, placebo‐controlled clinical trials (RCTs). A systematic literature search in SCOPUS, PubMed‐Medline, ISI Web of Science, and Google Scholar databases was conducted up to October 2, 2018, in order to identify RCTs assessing changes in plasma concentrations of total cholesterol (TC), triglycerides (TG), high‐density lipoprotein cholesterol (HDL‐C), low‐density lipoprotein cholesterol (LDL‐C) and FPG during treatment with berberine and silymarin in combination. Two review authors independently extracted data on study characteristics, methods, and outcomes. Quantitative data synthesis was performed using a random‐effects model. We identified five eligible RCTs, with 497 subjects overall included. Berberine and silymarin combination treatment exerted a positive effect on TC (mean difference [MD]: −25.3, 95% CI [−39.2, −11.4] mg/dl; p < 0.001), TG (MD: −28, 95% CI [−35.3, −20.6] mg/dl; p < 0.001), HDL‐C [MD: 6, 95% CI [3.2, 8.8] mg/dl; p < 0.001), LDL‐C (MD: −29.1, 95% CI [−39.7, −18.6] mg/dl; p < 0.001), and FPG (MD: −7.5, 95% CI [−13, −1.9] mg/dl; p = 0.008). The present findings suggest that the coadministration of berberine and silymarin is associated with an advantageous improvement in lipid and glucose profile, suggesting the possible use of this nutraceutical combination in order to promote the cardiometabolic health.
Robust stability analysis of fractional‐order interval systems with multiple time delays
Authors: Mohsenipour Reza , Fathi Jegarkandi Mohsen
Published: January 2019

This paper investigates the robust stability analysis of fractional‐order interval systems with multiple time delays, including retarded and neutral systems. A bound on the poles of fractional‐order interval systems of retarded and neutral type is obtained. Then, the concept of the value set and zero exclusion principle is extended to these systems, and a necessary and sufficient condition is produced for checking the robust stability of them. The value set of the characteristic equation of the systems is obtained analytically and, based on it, an auxiliary function is introduced to check the zero exclusion principle. Finally, two numerical examples are given to illustrate the effectiveness of the results presented.
Effect of Crystal Phase of MnO2 with Similar Nanorod‐Shaped Morphology on the Catalytic Performance of Benzene Combustion
Authors: Hu Zhun , Mi Rongli , Yong Xiang , Liu Shuang , Li Dan , Li Yu , Zhang Tao
Published: January 2019

Four manganese oxides with different crystal structures in the similar nanorod‐shaped morphology were synthesized and investigated for the catalytic combustion of benzene. The physicochemical properties of the materials were characterized by N2 physisorption‐desorption, transmission electron microscope (TEM), X‐ray photoelectron spectroscopy (XPS), Raman spectra, O2 temperature programmed desorption (O2‐TPD) and temperature programmed surface reaction (TPSR). The catalytic activities on benzene combustion over various manganese oxides decreased in the order: γ‐MnO2 > β‐MnO2 > α‐MnO2 > δ‐MnO2. The activation energy of benzene combustion over γ‐MnO2 (67.4 kJ/mol) was lower than that over α‐MnO2 (69.2 kJ/mol), β‐MnO2 (79.1 kJ/mol) and δ‐MnO2 (85.2 kJ/mol). The TPSR results with or without gaseous oxygen revealed that the reaction pathway was occurred via MVK mechanism. The surface adsorbed oxygen species concentration and low temperature O2 desorption of these manganese oxides, determined by XPS and O2‐TPD, decreased in the order of γ‐MnO2 > β‐MnO2 > α‐MnO2 > δ‐MnO2, are in good agreement with the sequence of their catalytic performance on benzene combustion. It is concluded that higher surface adsorbed oxygen species ratio and better low temperature O2 desorption were crucial to the superior catalytic performance of the α‐MnO2, β‐MnO2, γ‐MnO2 and δ‐MnO2 materials.
Renewable‐Resource‐Based Waste Materials for Supercapacitor Application
Authors: Macchi Samantha , Siraj Noureen , Watanabe Fumiya , Viswanathan Tito
Published: January 2019

Herein, renewable resource‐based waste materials (used tea leaves and molasses) were utilized as inexpensive and renewable carbon sources to develop Phosphorus and Nitrogen co‐doped Carbon (PNDC) materials for supercapacitor application. A prompt, low cost, single step, green and facile microwave assisted process was utilized to prepare PNDC materials using the aforementioned biomass. Concentration of the doping elements (P and N) was altered in the resulting PNDC materials by varying the mole ratio of used tea/molasses and ammonium polyphosphate (APP) in the reaction mixture. APP served as the Phosphorus and Nitrogen source as well as the microwave absorber. Detailed characterization of all four PNDCs ‐ two derived from molasses (MOLPNDCs) and two from used tea leaves (TEAPNDCs), were performed to investigate their supercapacitor performance. These materials were characterized both physically via BET, XPS, and SEM analysis and electrochemically via cyclic voltammetry, in both 1 M H2SO4 and 6 M KOH. Pore size, surface area, and elemental compositions of each PNDC was analyzed to investigate the critical parameter for supercapacitor performance of the materials. Among all PNDCs, MOLPNDC‐1 exhibited exceptionally high specific capacitance values of 160 Fg−1 in 6 M KOH electrolyte due to highly mesoporous structure and appropriate Nitrogen content. MOLPNDC‐1 was also found to be stable under continuous cycling for 1500 cycles in both acidic and alkaline conditions.
Dual‐Function, Tunable, Nitrogen‐Doped Carbon for High‐Performance Li Metal–Sulfur Full Cell
Authors: Li Hongyan , Cheng Zheng , Natan Avi , Hafez Ahmed M. , Cao Daxian , Yang Yang , Zhu Hongli
Published: January 2019

Lithium metal–sulfur (Li–S) batteries are attracting broad interest because of their high capacity. However, the batteries experience the polysulfide shuttle effect in cathode and dendrite growth in the Li metal anode. Herein, a bifunctional and tunable mesoporous carbon sphere (MCS) that simultaneously boosts the performance of the sulfur cathode and the Li anode is designed. The MCS homogenizes the flux of Li ions and inhibits the growth of Li dendrites due to its honeycomb structure with high surface area and abundance of nitrogen sites. The Li@MCS cell exhibits a small overpotential of 29 mV and long cycling performance of 350 h under the current density of 1 mA cm‐2. Upon covering one layer of amorphous carbon on the MCS (CMCS), an individual carbon cage is able to encapsulate sulfur inside and reduce the polysulfide shuttle, which improves the cycling stability of the Li–S battery. As a result, the S@CMCS has a maximum capacity of 411 mAh g‐1 for 200 cycles at a current density of 3350 mA g‐1. Based on the excellent performance, the full Li–S cell assembled with Li@MCS anode and S@CMCS cathode shows much higher capacity than a cell assembled with Li@Cu anode and S@CMCS cathode.
Component‐Interaction Reinforced Quasi‐Solid Electrolyte with Multifunctionality for Flexible Li–O2 Battery with Superior Safety under Extreme Conditions
Authors: Shu Chaozhu , Long Jianping , Dou Shi‐Xue , Wang Jiazhao
Published: January 2019

High‐performance flexible lithium–oxygen (Li–O2) batteries with excellent safety and stability are urgently required due to the rapid development of flexible and wearable devices. Herein, based on an integrated solid‐state design by taking advantage of component‐interaction between poly(vinylidene fluoride‐co‐hexafluoropropylene) and nanofumed silica in polymer matrix, a stable quasi‐solid‐state electrolyte (PS‐QSE) for the Li–O2 battery is proposed. The as‐assembled Li–O2 battery containing the PS‐QSE exhibits effectively improved anodic reversibility (over 200 cycles, 850 h) and cycling stability of the battery (89 cycles, nearly 900 h). The improvement is attributed to the stability of the PS‐QSE (including electrochemical, chemical, and mechanical stability), as well as the effective protection of lithium anode from aggressive soluble intermediates generated in cathode. Furthermore, it is demonstrated that the interaction among the components plays a pivotal role in modulating the Li‐ion conducting mechanism in the as‐prepared PS‐QSE. Moreover, the pouch‐type PS‐QSE based Li–O2 battery also shows wonderful flexibility, tolerating various deformations thanks to its integrated solid‐state design. Furthermore, holes can be punched through the Li–O2 battery, and it can even be cut into any desired shape, demonstrating exceptional safety. Thus, this type of battery has the potential to meet the demands of tailorability and comformability in flexible and wearable electronics.
Sharpen statistical significance: Evidence thresholds and Bayes factors sharpened into Occam's razor
Authors: Bickel David R.
Published: January 2019

Occam's razor suggests assigning more prior probability to a hypothesis corresponding to a simpler distribution of data than to a hypothesis with a more complex distribution of data, other things equal. An idealization of Occam's razor in terms of the entropy of the data distributions tends to favor the null hypothesis over the alternative hypothesis. As a result, lower p values are needed to attain the same level of evidence. A recently debated argument for lowering the significance level to 0.005 as the p value threshold for a new discovery and to 0.05 for a suggestive result would then support further lowering them to 0.001 and 0.01, respectively.
An experimental characterization of the friction coefficient of a wind turbine gearbox lubricant
Authors: Nutakor Charles , Talbot David , Kahraman Ahmet
Published: January 2019

In this study, a method to predict the contact friction coefficients at the rolling‐sliding contacts of isotropic superfinished and axially ground gear and bearing surfaces in wind turbine gearboxes is proposed. A two‐disc test rig was used to measure friction coefficient values within a slide‐to‐roll ratio range of −0.8 to 0.8, rolling velocities of 2 to 12 m/s, at oil temperatures of 50°C, 70°C, and 100°C and Hertzian contact pressures of 1.2, 1.6, and 2.0 GPa. A polyalphaolefin (PAO) International Standards Organization (ISO) viscosity grade (VG) 320 was the lubricant. Data from 90 individual friction coefficient tests were combined to develop two closed‐form friction coefficient formulae. A multivariable linear regression analysis was used to derive the regressed formulae. Using the developed regressed formulae, the predicted friction values follow the trend of measured values at all of the operating conditions. The results show that the regressed formulae are close to experimental friction coefficient values. The friction coefficient predictions confirm that the regressed formulae are capable of simulating contact friction values for the lubricated contact conditions considered.
E7(7) exceptional field theory in superspace
Authors: Butter Daniel , Samtleben Henning , Sezgin Ergin
Published: January 2019

Abstract

We formulate the locally supersymmetric E7(7) exceptional field theory in a (4 + 56|32) dimensional superspace, corresponding to a 4D N = 8 “external” superspace augmented with an “internal” 56-dimensional space. This entails the unification of external diffeomorphisms and local supersymmetry transformations into superdiffeomorphisms. The solutions to the superspace Bianchi identities lead to on-shell duality equations for the p-form field strengths for p ≤ 4. The reduction to component fields provides a complete description of the on-shell supersymmetric theory. As an application of our results, we perform a generalized Scherk-Schwarz reduction and obtain the superspace formulation of maximal gauged supergravity in four dimensions parametrized by an embedding tensor.
Neutrino scattering and B anomalies from hidden sector portals
Authors: Datta Alakabha , Dutta Bhaskar , Liao Shu , Marfatia Danny , Strigari Louis E.
Published: January 2019

Abstract

We examine current constraints on and the future sensitivity to the strength of couplings between quarks and neutrinos in the presence of a form factor generated from loop effects of hidden sector particles that interact with quarks via new interactions. We consider models associated with either vector or scalar interactions of quarks and leptons generated by hidden sector dynamics. We study constraints on these models using data from coherent elastic neutrino-nucleus scattering and solar neutrino experiments and demonstrate how these new interactions may be discovered by utilizing the recoil spectra. We show that our framework can be naturally extended to explain the lepton universality violating neutral current B decay anomalies, and that in a model framework the constraints from neutrino scattering can have implications for these anomalies.
Schwarzschild/CFT from soft black hole hair?
Authors: Averin Artem
Published: January 2019

Abstract

Recent studies of asymptotic symmetries suggest, that a Hamiltonian phase space analysis in gravitational theories might be able to account for black hole microstates. In this context we explain, why the use of conventional Bondi fall-off conditions for the gravitational field is too restrictive in the presence of an event horizon. This implies an enhancement of physical degrees of freedom (

$$ \mathcal{A} $$

A

-modes). They provide new gravitational hair and are responsible for black hole microstates. Using covariant phase space methods, for the example of a Schwarzschild black hole, we give a proposal for the surface degrees of freedom and their surface charge algebra. The obtained two-dimensional dual theory is conjectured to be conformally invariant as motivated from the criticality of the black hole. Carlip’s approach to entropy counting reemerges as a Sugawara-construction of a 2D stress-tensor.