bluuebunny/crossref_metadata_2025 huggingface dataset:
Downregulation of histone methyltransferase SET8 inhibits progression of hepatocellular carcinoma
Authors: Wu Jianhua , Qiao Kuangyuan , Du Yanming , Zhang Xiaoyun , Cheng Haichao , Peng Li , Guo Zhanjun
Published: March 2020

The expression of lysine methyltransferase SET8, which is involved in carcinogenesis of many types of human cancers through monomethylation of histone H4 lysine 20 (H4K20), is associated with the prognosis of hepatocellular carcinoma (HCC). We performed a functional analysis for SET8 to assess its effect on HCC progression. SET8 knockdown inhibited proliferation, migration and invasion of HCC cells. SET8 knockdown also inhibited tumour growth in a human xenograft mouse model. Overexpression of SET8 displayed the reverse effect, while treatment with the SET8 inhibitor UNC0379 produced an effect similar to SET8 knockdown. In addition, drug sensitivity testing in SET8-siRNA transfected HCC cells indicated that docetaxel inhibited cell growth dramatically, as demonstrated by the Cell Counting Kit-8 (CCK-8) assay. Furthermore, gene expression microarray analysis showed that genes altered after SET8 knockdown were clustered in pathways related to tumorigenesis and metastasis. Our data suggests that targeting SET8 for HCC therapy can inhibit the proliferation and invasion of HCC cells as well as increase their sensitivity to chemotherapy.
Nintedanib ameliorates animal model of dermatitis
Authors: Heo Min-Jeong , Lee Chanmi , Choi Soo Young , Choi Yeong Min , An In-sook , Bae Seunghee , An Sungkwan , Jung Jin Hyuk
Published: March 2020

Nintedanib, a receptor tyrosine kinase (RTK) inhibitor has been developed as therapeutics for idiopathic pulmonary fibrosis and non-small lung cancer. We found that the expression levels of RTK, especially VEGFR1 is increased in skin biopsies of dermatitis patients from multiple independent datasets. Moreover, VEGFR1 is highly expressed by infiltrated cells in dermis from oxazolone (OXA) treated mice. Interestingly, nintedanib alleviates dermatitis symptom in OXA-induced animal model. Especially, levels of epidermis thickness, infiltrated immune cells including mast cells and eosinophils were decreased from mice cotreated with nintedanib and OXA compared with OXA treated mice. Moreover, serum IgE and Th2 cytokines including IL-4 and IL-13 were decreased by nintedanib treatment. These results suggest an evidence that nintedanib alleviates animal model of dermatitis.
Phonatory and articulatory representations of speech production in cortical and subcortical fMRI responses
Authors: Correia Joao M. , Caballero-Gaudes César , Guediche Sara , Carreiras Manuel
Published: March 2020

Speaking involves coordination of multiple neuromotor systems, including respiration, phonation and articulation. Developing non-invasive imaging methods to study how the brain controls these systems is critical for understanding the neurobiology of speech production. Recent models and animal research suggest that regions beyond the primary motor cortex (M1) help orchestrate the neuromotor control needed for speaking, including cortical and sub-cortical regions. Using contrasts between speech conditions with controlled respiratory behavior, this fMRI study investigates articulatory gestures involving the tongue, lips and velum (i.e., alveolars versus bilabials, and nasals versus orals), and phonatory gestures (i.e., voiced versus whispered speech). Multivariate pattern analysis (MVPA) was used to decode articulatory gestures in M1, cerebellum and basal ganglia. Furthermore, apart from confirming the role of a mid-M1 region for phonation, we found that a dorsal M1 region, linked to respiratory control, showed significant differences for voiced compared to whispered speech despite matched lung volume observations. This region was also functionally connected to tongue and lip M1 seed regions, underlying its importance in the coordination of speech. Our study confirms and extends current knowledge regarding the neural mechanisms underlying neuromotor speech control, which hold promise to study neural dysfunctions involved in motor-speech disorders non-invasively.
Super impact stable TATB explosives recrystallized by bicarbonate ionic liquids with a record solubility
Authors: Yuan Wen-Li , Tao Guo-Hong , Zhang Lei , Zhang Zhang , Xue Ying , He Ling , Huang Jinglun , Yu Weifei
Published: March 2020

Ensuring the security for long-term storage of weapons is always of the great cMehilaloncerns in the field of energetic materials. 1,3,5-Triamino-2,4,6-trinitrobenzene (TATB) is a remarkable explosive applied in nuclear weapons where extreme safety is required primarily. Owing to the strong inter or intra molecular hydrogen bonding, TATB shows poor solubility in most solvents. As the result, the particle shape and size of TATB products is hard to regulate, which closely related to the weapons stability. Herein, a new recrystallization method is provided to refine TATB using bicarbonate ionic liquids. Bicarbonate ionic liquids exhibited the record solubility (26.7 wt%) for dissolving TATB explosive. The recrystallized TATB were spherical particles with uniform size and showed extremely insensitivity to impact (>100 J) and friction (>360 N). Moreover, the experimental1H and13C NMR spectra of TATB in solution are reported for the first time.
Aureobasidium pullulans volatilome identified by a novel, quantitative approach employing SPME-GC-MS, suppressed Botrytis cinerea and Alternaria alternata in vitro
Authors: Yalage Don S. M. , Schmidtke L. M. , Gambetta J. M. , Steel C. C.
Published: March 2020

Volatile organic compounds (VOCs) produced by Aureobasidium pullulans were investigated for antagonistic actions against Alternaria alternata and Botrytis cinerea. Conidia germination and colony growth of these two phytopathogens were suppressed by A. pullulans VOCs. A novel experimental setup was devised to directly extract VOCs using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) from antagonist-pathogen culture headspace. The proposed system is a robust method to quantify microbial VOCs using an internal standard. Multivariate curve resolution-alternating least squares deconvolution of SPME-GC-MS spectra identified fourteen A. pullulans VOCs. 3-Methyl-1-hexanol, acetone, 2-heptanone, ethyl butyrate, 3-methylbutyl acetate and 2-methylpropyl acetate were newly identified in A. pullulans headspace. Partial least squares discriminant analysis models with variable importance in projection and selectivity ratio identified four VOCs (ethanol, 2-methyl-1-propanol, 3-methyl-1-butanol and 2-phenylethanol), with high explanatory power for discrimination between A. pullulans and pathogen. The antifungal activity and synergistic interactions of the four VOCs were evaluated using a Box-Behnken design with response surface modelling. Ethanol and 2-phenylethanol are the key inhibitory A. pullulans VOCs against both B. cinerea and A. alternata. Our findings introduce a novel, robust, quantitative approach for microbial VOCs analyses and give insights into the potential use of A. pullulans VOCs to control B. cinerea and A. alternata.
Electrochemical Degradation of Reactive Black 5 using two-different reactor configuration
Authors: Droguett Tamara , Mora-Gómez Julia , García-Gabaldón Montserrat , Ortega Emma , Mestre Sergio , Cifuentes Gerardo , Pérez-Herranz Valentín
Published: March 2020

Novel Sb-doped SnO2 ceramic electrodes sintered at different temperatures, are applied to the degradation of Reactive Black 5 in both divided and undivided electrochemical reactors. In the undivided reactor the discoloration of the solution took place via the oxidation of RB5 dye, without the corresponding reduction in the chemical oxygen demand for the ceramic electrodes. However, in the divided one, it was possible to achieve the discoloration of the solution while at the same time decreasing the chemical oxygen demand through the ·OH-mediated oxidation, although the chemical oxygen demand degradation took place at a slower rate.
In vivo engineering of lymphocytes after systemic exosome-associated AAV delivery
Authors: Breuer Cort B. , Hanlon Killian S. , Natasan Jeya-shree , Volak Adrienn , Meliani Amine , Mingozzi Federico , Kleinstiver Benjamin P. , Moon James J. , Maguire Casey A.
Published: March 2020

Ex-vivo gene therapy using stem cells or T cells transduced by retroviral or lentiviral vectors has shown remarkable efficacy in the treatment of immunodeficiencies and cancer. However, the process is expensive, technically challenging, and not readily scalable to large patient populations, particularly in underdeveloped parts of the world. Direct in vivo gene therapy would avoid these issues, and such approaches with adeno-associated virus (AAV) vectors have been shown to be safe and efficacious in clinical trials for diseases affecting differentiated tissues such as the liver and CNS. However, the ability to transduce lymphocytes with AAV in vivo after systemic delivery has not been carefully explored. Here, we show that both standard and exosome-associated preparations of AAV8 vectors can effectively transduce a variety of immune cell populations including CD4+ T cells, CD8+ T cells, B cells, macrophages, and dendritic cells after systemic delivery in mice. We provide direct evidence of T cell transduction through the detection of AAV genomes and transgene mRNA, and show that intracellular and transmembrane proteins can be expressed. These findings establish the feasibility of AAV-mediated in vivo gene delivery to immune cells which will facilitate both basic and applied research towards the goal of direct in vivo gene immunotherapies.
Publisher Correction: Population reference and healthy standard blood pressure range charts in pregnancy: findings from the Born in Bradford cohort study
Authors: Santorelli Gillian , Lawlor Debbie A. , West Jane , Tuffnell Derek , Farrar Diane
Published: March 2020

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Trace amounts of Cu(OAc)2 boost the efficiency of cumene oxidation catalyzed by carbon nanotubes washed with HCl
Authors: Deng Jie , Li Yuhang , Cao Yonghai , Wang Hongjuan , Yu Hao , Zhang Qiao , Zuo Jiangliang , Peng Feng
Published: March 2020

Trace amounts of Cu(OAc)2 significantly improve the activity and selectivity of cumene oxidation catalyzed by HCl-washed carbon nanotubes.
3D amorphous NiFe LDH nanosheets electrodeposited on in situ grown NiCoP@NC on nickel foam for remarkably enhanced OER electrocatalytic performance
Authors: Nie Jianhang , Hong Min , Zhang Xiaohua , Huang Junlin , Meng Qin , Du Cuicui , Chen Jinhua
Published: March 2020

3D amorphous NiFe LDH nanosheets electrodeposited on hierarchical porous and conductive NiCoP@NC/NF in situ grown on nickel foam exhibited outstanding OER catalytic activity and stability.
A new lithium diffusion model in layered oxides based on asymmetric but reversible transition metal migration
Authors: Ku Kyojin , Kim Byunghoon , Jung Sung-Kyun , Gong Yue , Eum Donggun , Yoon Gabin , Park Kyu-Young , Hong Jihyun , Cho Sung-Pyo , Kim Do-Hoon , Kim Hyungsub , Jeong Eunsuk , Gu Lin , Kang Kisuk
Published: March 2020

We propose a new lithium diffusion model involving coupled lithium and transition metal migration, peculiarly occurring in a lithium-rich layered oxide.
Development of an efficient and sustainable synthesis of 2-(3-methyl-1H-1,2,4-triazol-1-yl) acetic acid under continuous-flow conditions
Authors: Tortoioli Simone , Friedli Astrid , Prud'homme Alice , Richard-Bildstein Sylvia , Kohler Philipp , Abele Stefan , Vilé Gianvito
Published: March 2020

A novel, metal-free process for the challenging synthesis of 1,2,4-triazoles is reported, which features an efficient construction of the triazole ring under flow conditions.
A microfluidic device for digital manipulation of gaseous samples
Authors: Enel A. , Bourrelier A. , Vial J. , Thiébaut D. , Bourlon B.
Published: March 2020

The first device for digital manipulation of gaseous samples; from elementary operations to demonstration of a more complex application.
Evaluation of a multiple and global analytical indicator of batch consistency: traditional Chinese medicine injection as a case study
Authors: Chen Libing , Zhao Fang , Li Wenzhu , Chen Zeqi , Pan Jianyang , Xiong Difeifei , Li Bailing , Zhang Qingjie , Qu Haibin
Published: March 2020

Evaluation of a multiple and global analytical indicator of batch consistency was employed in TCMIs with a multivariate statistical tool.
Antidiabetic effect of two different Ganoderma species tested in alloxan diabetic rats
Authors: Rašeta Milena , Popović Mira , Čapo Ivan , Stilinović Nebojša , Vukmirović Saša , Milošević Biljana , Karaman Maja
Published: March 2020

Antidiabetic potentials of G. pfeifferi and G. resinaceum were obtained in this study and found to be of even higher bioactivity than the previously reported and well known G. lucidum.
Synthesis of a hierarchical carbon fiber@cobalt ferrite@manganese dioxide composite and its application as a microwave absorber
Authors: Feng Ailing , Hou Tianqi , Jia Zirui , Wu Guanglei
Published: March 2020

In this study, a novel hierarchical carbon fiber@cobalt ferrite@manganese dioxide (CF@CoFe2O4@MnO2) composite was facilely prepared via a sol–gel method and hydrothermal reaction.
pH-Dependent transfer hydrogenation or dihydrogen release catalyzed by a [(η6-arene)RuCl(κ2-N,N-dmobpy)]+ complex: a DFT mechanistic understanding
Authors: Luo Chenguang , Li Longfei , Yue Xin , Li Pengjie , Zhang Lin , Yang Zuoyin , Pu Min , Cao Zexing , Lei Ming
Published: March 2020

A DFT mechanistic study has been performed to unveil the nature of preference of transfer hydrogenation of ketones and dihydrogen release catalyzed by single-site cyclometallated ruthenium complexes under different pH environments.
Entropy estimates of a hard sphere system by data compression of Monte Carlo simulation data
Authors: Walraven E. F. , Leermakers F. A. M.
Published: March 2020

How to obtain the entropy? (1) Monte Carlo simulation; (2) store snapshots in a file; (3) apply data compression; and (4) get entropy from the compressibility.
Printing on liquid elastomers
Authors: Cai Lingzhi , Marthelot Joel , Falcón Claudio , Reis Pedro M. , Brun P.-T.
Published: March 2020

We propose a robust fluid-mediated route for the rapid fabrication of soft elastomers architected with liquid inclusions. Our approach consists of printing water at the surface of an immiscible liquid elastomer bath, which subsequently cures.
Hydrothermal synthesis of boron-free Zr-MWW and Sn-MWW zeolites as robust Lewis acid catalysts
Authors: Zhu Zhiguo , Guan Yejun , Ma Haikuo , Xu Hao , Jiang Jin-gang , Lü Hongying , Wu Peng
Published: March 2020

Boron-free Zr-MWW and Sn-MWW metallosilicates were synthesized via dual structure-directing agent-facilitated crystallization, which demonstrated unique catalytic behavior in Meerwein–Pondorf–Verley and Baeyer–Villiger oxidation reactions.
Nuclear quantum effects in enzymatic reactions: simulation of the kinetic isotope effect of phenylethylamine oxidation catalyzed by monoamine oxidase A
Authors: Prah Alja , Ogrin Peter , Mavri Janez , Stare Jernej
Published: March 2020

By using computational techniques for quantizing nuclear motion one can accurately reproduce kinetic isotope effect of enzymatic reactions, as demonstrated for phenylethylamine oxidation catalyzed by the monoamine oxidase A enzyme.
Enhanced visible light-active CeO2/CuO/Ag2CrO4 ternary heterostructures based on CeO2/CuO nanofiber heterojunctions for the simultaneous degradation of a binary mixture of dyes
Authors: Sabzehmeidani Mohammad Mehdi , Karimi Hajir , Ghaedi Mehrorang
Published: March 2020

CeO2/CuO/Ag2CrO4 composite is fabricated using an electrospinning and precipitation. Also, composite can photodegrade RB and MB under visible light irradiation. CeO2/CuO/Ag2CrO4 can enhanced photocatalytic activity due to formed heterojunction.
Visible-light-driven conversion of organic compounds over WO3-based microtubes with mesoporous-walled structure
Authors: Lv Ying , Xu Zhanglian , Du Lei
Published: March 2020

Pd-WO3 microtubes demonstrated complete oxidation of dye molecules and partial oxidation of propan-2-ol with high selectivity for acetone generation.
Imaging of endoplasmic reticulum superoxide anion fluctuation in a liver injury model by a selective two-photon fluorescent probe
Authors: Zuo Qingping , Wu Qian , Lv Yun , Gong Xiangyang , Cheng Dan
Published: March 2020

An endoplasmic reticulum-targeted two-photon probe is reported with excellent sensitivity and selectivity for visualizing the O2˙− level in a liver injury model.
Exploring functionalized titania for task specific application of efficient separation of trivalent f-block elements
Authors: Pahan Sumit , Sengupta Arijit , Yadav A. K. , Jha S. N. , Bhattacharyya D. , Musharaf Ali Sk. , Khan P. N. , Debnath A. K. , Banerjee D. , Vincent T. , Manohar S. , Kaushik C. P.
Published: March 2020

Functionalized titania, obtained by grafting the dipicolinic acid functionality, was explored for task specific application of highly efficient separation of trivalent f-block elements.
Construction of coumarin-fused pyrido[2,3-b]porphyrins through a trichloroacetic acid-accelerated domino approach
Authors: Tekuri Chandra Sekhar , Singh Pargat , Nath Mahendra
Published: March 2020

A one-pot strategy for coumarin-fused Ni(ii) and Cu(ii) pyrido[2,3-b]porphyrins is developed. These porphyrinoids displayed a significant red-shift in their UV-Vis spectra.
Metal-free and regiospecific synthesis of 3-arylindoles
Authors: Xu Chuangchuang , Xie Wenlai , Xu Jiaxi
Published: March 2020

A microwave-assisted acid and base co-catalyzed strategy shows high efficiency in the synthesis of 3-arylindoles through tandem nucleophilic ring-opening and Fischer indolization of aryloxiranecarbonitriles and arylhydrazine hydrochlorides.
Characterization of bitumen and a novel multiple synergistic method for reducing bitumen viscosity with nanoparticles and surfactants
Authors: Liu Yunfeng , Qiu Zhengsong , Zhao Chong , Nie Zhen , Zhong Hanyi , Zhao Xin , Liu Shujie , Xing Xijin
Published: March 2020

This paper is concerned with the formation of bitumen during the drilling of the H oilfield in Iraq.
Cesium polytungstates with blue-tint-tunable near-infrared absorption
Authors: Yoshio Satoshi , Wakabayashi Masao , Adachi Kenji
Published: March 2020

Revisiting Wöhler's method (1824), Cs-doped tungsten bronzes were synthesized by reducing Cs-polytungstate at high temperature, and were pulverized into nanoparticles for determining their optical properties.
New reductive rearrangement of N-arylindoles triggered by the Grubbs–Stoltz reagent Et3SiH/KOtBu
Authors: Smith Andrew J. , Dimitrova Daniela , Arokianathar Jude N. , Kolodziejczak Krystian , Young Allan , Allison Mark , Poole Darren L. , Leach Stuart G. , Parkinson John A. , Tuttle Tell , Murphy John A.
Published: March 2020

N-Arylindoles are transformed into dihydroacridines in a new type of rearrangement, through heating with triethylsilane and potassium tert-butoxide.
Linking the evolution of catalytic properties and structural changes in copper–zinc nanocatalysts using operando EXAFS and neural-networks
Authors: Timoshenko Janis , Jeon Hyo Sang , Sinev Ilya , Haase Felix T. , Herzog Antonia , Roldan Cuenya Beatriz
Published: March 2020

A neural network is used to reveal composition-dependent structural evolution under operando conditions in CuZn nanocatalysts for CO2 electroreduction.
Pattern formation in two-dimensional hard-core/soft-shell systems with variable soft shell profiles
Authors: Somerville Walter R. C. , Law Adam D. , Rey Marcel , Vogel Nicolas , Archer Andrew J. , Buzza D. Martin A.
Published: March 2020

Hard-core/soft-shell particles with experimentally realistic interactions can form honeycombs and quasicrystals.
Revealing the oxygen reduction reaction activity origin of single atoms supported on g-C3N4 monolayers: a first-principles study
Authors: Niu Huan , Wang Xiting , Shao Chen , Liu Yuanshuang , Zhang Zhaofu , Guo Yuzheng
Published: March 2020

Pd/g-C3N4 stands out for the ORR, and multiple-level descriptors involving basic characteristics, electronic structures, charge transfer and energy are established.
Recent advances in conjugated microporous polymers for photocatalysis: designs, applications, and prospects
Authors: Luo Songhao , Zeng Zhuotong , Zeng Guangming , Liu Zhifeng , Xiao Rong , Xu Piao , Wang Han , Huang Danlian , Liu Yang , Shao Binbin , Liang Qinghua , Wang Dongbo , He Qingyun , Qin Lei , Fu Yukui
Published: March 2020

Conjugated microporous polymers (CMPs) provide a platform to construct light harvesting systems and catalytic centers to realize solar energy conversion.
Simple/efficient phosphor-only emitting systems: from sky-blue to warm-white organic electroluminescence based on a novel bipolar phosphorescent emitter as the host
Authors: Zhuang Xuming , Liu Xinze , Chen Shuonan , Zhang Hao , Liu Yu , Wang Yue
Published: March 2020

A simple single-emitting layer only containing two phosphors ofFMPYPCA(sky blue)/BZQBA(orange red) realizes a high-quality warm-white electroluminescence with CIEx,yof (0.42, 0.45) and very high peak efficiencies of 22.4%/65.4 lm W−1.
Robust palmprint identification using efficient enhancement and two‐stage matching technique
Authors: Ghafoor Mubeen , Tariq Syed Ali , Taj Imtiaz A. , Jafri Noman M. , Zia Tehseen
Published: March 2020

Palmprint‐based human authentication has shown great potential for civil, forensic, and corporate security applications in recent years. Palmprint recognition systems suffer because of large palmprint sizes and the presence of a large number of creases and erroneous minutiae that make the enhancement and matching phases a challenge. In this study, a novel approach is presented based on efficient enhancement and a two‐stage matching technique that demonstrates highly accurate identification results. The enhancement approach extracts minutia features from high‐quality regions based on local ridge characteristics. The selected minutiae are then matched using a two‐stage local and global minutiae neighbour‐based matching technique. To demonstrate the performance of the proposed technique, comparisons with open‐source algorithms are made based on equal error rate and detection error trade‐off graph. The results confirm the efficacy of proposed palmprint enhancement and identification technique.
Fast fractal image compression algorithm using specific update search
Authors: Zheng Yunping , Li Xiangpeng , Sarem Mudar
Published: March 2020

The fractal image compression (FIC) algorithm is difficult to be widely used in real‐time applications due to the huge consumption of its encoding time. Inspired by the fact that in the decoding process, for any original image, a fixed point is generated by the iterations of the fractal codes, the authors propose a specific update search FIC (SUSFIC) algorithm, which uses a scale number to control the update times of the fractal codes and to find acceptable matching domain blocks rather than the best ones in the selected domain blocks pool. To further reduce the computation time, in their proposed algorithm, the image blocks created by the equidistant sampling in the range of the original blocks are used to replace themselves when calculating the correlation coefficients as the distances between the adjacent domain blocks. The experimental results presented show that their proposed SUSFIC algorithm has a significant improvement in encoding time under the premise of setting an appropriate search update threshold and maintaining image quality when compared with the state‐of‐the‐art FIC algorithms. Therefore, it is a better FIC algorithm.
Hierarchical morphological graph signal multi‐layer decomposition for editing applications
Authors: Lézoray Olivier
Published: March 2020

The authors address the problem of editing signals such as 2D colour images or 3D coloured meshes that are represented under the general framework of graph signals. As state‐of‐the‐art editing approaches decompose an image into several layers in order to manipulate them, they propose a hierarchical multi‐layer decomposition of graph signals that relies on morphological filtering. Since morphological filtering operators require a complete lattice, a dedicated approach for the morphological processing of vectorial data on graphs is used. By iterating the application of morphological filterings of decreasing sizes, the graph signal is decomposed into several detail layers, each capturing a given detail level. Editing applications such as abstraction, sharpness enhancement and tone mapping are shown to illustrate the benefits of the proposed approach.
Accelerating convolutional neural network training using ProMoD backpropagation algorithm
Authors: Gürhanlı Ahmet
Published: March 2020

Convolutional neural networks (CNNs) play an important role in image recognition applications. Fast training of image recognition systems is a crucial point, because the system should be trained for each new image class. These networks are trained using lengthy calculations. Focus of engineering is on obtaining a fast, but stable optimisation method. Momentum technique which is used in backpropagation algorithms is like a proportional–integral (PI) controller that is widely employed in automatic control systems. It takes the integral of past errors and helps reaching the training targets. Proportional + momentum + derivative (ProMoD) method adds gradient of update matrices to the training process and builds an optimiser such as the widely used PI–derivative controller. The method accelerates the movement toward the target accuracy levels. This is achieved by doing bigger corrections in the beginning using the differences in the calculated update matrices. In this research, ProMoD method is tested on image recognition applications and CNNs. Modified national institute of standards and technology database (MNIST) and Fashion‐MNIST datasets are used for evaluating the performance. Experimental results showed that ProMoD might perform much faster in training of CNNs and consume proportionally less power with respect to the momentum and stochastic gradient descent (SGD) techniques.
Higher order PDE based model for segmenting noisy image
Authors: Rathish Kumar B.V. , Halim Abdul , Vijayakrishna Rowthu
Published: March 2020

In this study, a fourth‐order non‐linear partial differential equation (PDE) model together with multi‐well potential has been proposed for greyscale image segmentation. The multi‐well potential is constructed from the histogram of the given image to make the segmentation process fully automatic and unsupervised. Further, the model is refined for effective segmentation of noisy greyscale image. The fourth‐order anisotropic term with the multi‐well potential is shown to properly segment noisy images. Fourier spectral method in space with semi‐implicit convexity splitting in time is used to derive an unconditionally stable scheme. Numerical studies on some standard test images and comparison of results with those in literature clearly depict the superiority of the anisotropic variant of the non‐linear PDE model.
Requirements for control strategies of grid‐connected converters in the future power system
Authors: Emanuel Hanna , Brombach Johannes , Rosso Roberto , Pierros Konstantinos
Published: March 2020

The increasing penetration of converter‐based generation in many power systems around the world has sparked a discussion about how to operate these power systems with the usual levels of efficiency, reliability and cost‐effectiveness. Current grid‐following converter‐based generators have proven to run stably in parallel to one another, even if there are thousands of them connected in a power system, and even in very small isolated power systems with extremely low system inertia. Discussions around the necessity of additional converter performance, usually under the ‘grid‐forming’ and ‘Virtual Synchronous Machines’ concepts, have recently been transferred from the academic sphere to national and international industry fora. Formal discussions have started in Great Britain, in Germany and at ENTSO‐E level. However, there is still a lot of uncertainty about the real and not simulated performance of grid‐forming converters, whilst the needs case for requiring this radically different control method has not been adequately justified. With the present paper we raise key questions that will serve towards an objective discussion about power system needs, grid infeed technologies and their interaction.
Constraining the masses of microlensing black holes and the mass gap with Gaia DR2
Authors: Wyrzykowski Łukasz , Mandel Ilya
Published: March 2020

Context. Gravitational microlensing is sensitive to compact-object lenses in the Milky Way, including white dwarfs, neutron stars, or black holes, and could potentially probe a wide range of stellar-remnant masses. However, the mass of the lens can be determined only in very limited cases, due to missing information on both source and lens distances and their proper motions.

Aims. Our aim is to improve the mass estimates in the annual parallax microlensing events found in the eight years of OGLE-III observations towards the Galactic Bulge with the use of Gaia Data Release 2 (DR2).

Methods. We use Gaia DR2 data on distances and proper motions of non-blended sources and recompute the masses of lenses in parallax events. We also identify new events in that sample which are likely to have dark lenses; the total number of such events is now 18.

Results. The derived distribution of masses of dark lenses is consistent with a continuous distribution of stellar-remnant masses. A mass gap between neutron star and black hole masses in the range between 2 and 5 solar masses is not favoured by our data, unless black holes receive natal kicks above 20−80 km s−1. We present eight candidates for objects with masses within the putative mass gap, including a spectacular multi-peak parallax event with mass of 2.4−1.3+1.9 M⊙ located just at 600 pc. The absence of an observational mass gap between neutron stars and black holes, or conversely the evidence of black hole natal kicks if a mass gap is assumed, can inform future supernova modelling efforts.
Asymmetrical nebula of the M33 variable GR290 (WR/LBV)
Authors: Maryeva Olga V. , Koenigsberger Gloria , Karpov Sergey V. , Lozinskaya Tatiana A. , Egorov Oleg V. , Rossi Corinne , Calabresi Massimo , Viotti Roberto F.
Published: March 2020

Context. GR 290 (M 33 V0532 = Romano’s star) is a luminous M 33 object undergoing photometric variability typical for luminous blue variable stars. It lies inside the Wolf-Rayet region in the Hertzsprung-Russell diagram and possesses a WN8-type spectrum at the light minima. Analysis of Gran Telescopio Canarias spectra obtained in 2016 led to the conclusion that it is surrounded by an unresolved H II region formed mostly of ejected material from the central star and revealed the presence of a second, more extended asymmetrical emission region.

Aims. The aim of this paper is to further explore the structure of the nearby environment of GR 290.

Methods. Long-slit spectra of GR 290 were obtained with three slit orientations in the visual and red spectral regions. The emission-line distribution for each slit was analyzed.

Results. We confirm the presence of an asymmetric H II region that extends ~50 pc to the south; ~30 pc to the north, and southeast; ~20 pc to the east and northwest; and ~10 pc to the west. We also present the first spectrum to be acquired of a star belonging to the neighboring OB 88 association, J013501.87+304157.3, which we classify as a B-type supergiant with a possible binary companion.
Phase mixing and wave heating in a complex coronal plasma
Authors: Howson T. A. , De Moortel I. , Reid J.
Published: March 2020

Aims. We investigate the formation of small scales and the related dissipation of magnetohydronamic (MHD) wave energy through non-linear interactions of counter-propagating, phase-mixed Alfvénic waves in a complex magnetic field.

Methods. We conducted fully three-dimensional, non-ideal MHD simulations of transverse waves in complex magnetic field configurations. Continuous wave drivers were imposed on the foot points of magnetic field lines and the system was evolved for several Alfvén travel times. Phase-mixed waves were allowed to reflect off the upper boundary and the interactions between the resultant counter-streaming wave packets were analysed.

Results. The complex nature of the background magnetic field encourages the development of phase mixing throughout the numerical domain, leading to a growth in alternating currents and vorticities. Counter-propagating phase-mixed MHD wave modes induce a cascade of energy to small scales and result in more efficient wave energy dissipation. This effect is enhanced in simulations with more complex background fields. High-frequency drivers excite localised field line resonances and produce efficient wave heating. However, this relies on the formation of large amplitude oscillations on resonant field lines. Drivers with smaller frequencies than the fundamental frequencies of field lines are not able to excite resonances and thus do not inject sufficient Poynting flux to power coronal heating. Even in the case of high-frequency oscillations, the rate of dissipation is likely too slow to balance coronal energy losses, even within the quiet Sun.

Conclusions. For the case of the generalised phase-mixing presented here, complex background field structures enhance the rate of wave energy dissipation. However, it remains difficult for realistic wave drivers to inject sufficient Poynting flux to heat the corona. Indeed, significant heating only occurs in cases which exhibit oscillation amplitudes that are much larger than those currently observed in the solar atmosphere.
An elastic model of Phobos’ libration
Authors: Yang Yongzhang , Yan Jianguo , Guo Xi , He Qingbao , Barriot Jean-Pierre
Published: March 2020

Context. Study the rotation of a celestial body is an efficient way to infer its interior structure, and then may give information of its origin and evolution. In this study, based on the latest shape model of Phobos from Mars Express (MEX) mission, the polyhedron approximation approach was used to simulate the gravity field of Phobos. Then, the gravity information was combined with the newest geophysical parameters such as GM and k2 to construct the numerical model of Phobos’ rotation. And with an appropriate angles transformation, we got the librational series respect to Martian mean equator of date.

Aims. The purpose of this paper is to develop a numerical model of Phobos’ rotational motion that includes the elastic properties of Phobos. The frequencies analysis of the librational angles calculated from the numerical integration results emphasize the relationship between geophysical properties and dynamics of Phobos. This work will also be useful for a future space mission dedicated to Phobos.

Methods. Based on the latest shape model of Phobos from MEX mission, we firstly modeled the gravity field of Phobos, then the gravity coefficients were combined with some of the newest geophysical parameters to simulate the rotational motion of Phobos. To investigate how the elastic properties of Phobos affect its librational motion, we adopted various k2 into our numerical integration. Then the analysis was performed by iterating a frequency analysis and linear least-squares fit of Phobos’ physical librations. From this analysis, we identified the influence of k2 on the largest librational amplitude and its phase.

Results. We showed the first ten periods of the librational angles and found that they agree well with the previous numerical results which Phobos was treated as a perfectly rigid body. We also found that the maximum amplitudes of the three parameters of libration are also close to the results from a rigid model, which is mainly due to the inclination of Phobos and moments of inertia. The other amplitudes are slightly different, since the physics contained in our model is different to that of a previous study, specifically, the different low-degree gravity coefficients and ephemeris. The libration in longitude τ has the same quadratic term with previous numerical study, which is consistent with the secular acceleration of Phobos falling onto Mars. We investigated the influence of the tidal Love number k2 on Phobos’ rotation and found a detectable amplitude changes (0.0005°) expected in the future space mission on τ, which provided a potential possibility to constrain the k2 of Phobos by observing its rotation. We also studied the influence of Phobos’ orbit accuracy on its libration and suggested a simultaneous integration of orbit and rotation in future work.
Quantum resources for energy storage
Authors: Ferraro Dario , Campisi Michele , Andolina Gian Marcello , Pellegrini Vittorio , Polini Marco
Published: March 2020

Recently the possibility to exploit quantum-mechanical effects to increase the performance of energy storage has raised a great interest. It consists of N two-level systems coupled to a single photonic mode in a cavity. We demonstrate the emergence of a quantum advantage in the charging power on this collective model (Dicke Quantum Battery) with respect to the one in which each two-level system is coupled to its own separate cavity mode (Rabi Quantum Battery). Moreover, we discuss the model of a Quantum Supercapacitor. This consists of two chains, one containing electrons and the other one holes, hosted by arrays of double quantum dots. The two chains are in close proximity and embedded in the same photonic cavity, in the same spirit of the Dicke model. We find the phase diagram of this model showing that, when transitioning from the ferro/antiferromagnetic to the superradiant phase, the quantum capacitance of the model is greatly enhanced.
Non thermal effects of radiofrequency electromagnetic field exposure on neural cells
Authors: Grasso Rosaria , Pellitteri Rosalia , Caravella Santi Armando , Musumeci Francesco , Raciti Giuseppina , Scordino Agata , Sposito Giovanni , Triglia Antonio , Campisi Agata
Published: March 2020

The non-thermal mechanisms, underlying the damage induced on human cells by radiofrequency electromagnetic fields (RF-EMFs), are still unclear and only few studies reported about the effect of RFEMFs on self-renewal of neural progenitor cells. In this research, we investigated the influence of low-intensity RF-EMFs on Olfactory Ensheathing Cell (OEC) cultures, typical glia cells showing characteristics of stem cells. Cell cultures were exposed, in far-field condition, at 900 MHz continuous and amplitude modulated EMFs for 10, 15 and 20 min at 37°C. The expression of OEC marker (S-100), stem cell marker (Nestin), cytoskeletal proteins (GFAP and Vimentin), apoptotic pathway activation by Caspase-3 cleavage and cell viability, were evaluated. Surprisingly 20 min of exposure to continuous or amplitude modulated 900 MHz EMF induced a different and significant decrease in cell viability, some dynamic changes in the expression of the analysed markers and in the activation of the apoptotic pathway.
Reshaping Hybrid Perovskites Emission with Flexible Polymer Microcavities
Authors: Lova Paola , Giusto Paolo , Di Stasio Francesco , Manfredi Giovanni , Paternò Giuseppe M. , Cortecchia Daniele , Soci Cesare , Comoretto Davide
Published: March 2020

Thanks to versatile optoelectronic properties solution processable perovskites have attracted increasing interest as active materials in photovoltaic and light emitting devices. However, the deposition of perovskite thin films necessitates wide range solvents that are incompatible with many other solution-processable media, including polymers that are usually dissolved by the perovskite solvents. In this work, we demonstrate that hybrid perovskite thin films can be coupled with all polymer planar photonic crystals with different approaches to achieve emission intensity enhancement and reshaping using different approaches. The possibility to control and modify the emission spectrum of a solution processable perovskite via a simple spun-cast polymer structure is indeed of great interest in optoelectronic applications requiring high color purity or emission directionality. Furthermore, thanks to the ease of fabrication and scalability of solution-processed photonic crystals, this approach could enable industrial scale production of low-cost, large area, lightweight and flexible polymer-perovskite lighting devices, which may be tuned without resorting to compositional engineering.
Development of compact neutron sources
Authors: Carpenter John M.
Published: March 2020

Many small research reactors, neutron sources built in the 1950s and 1960s are being shut down. The activities that these supported have therefore ended, which motivates their replacements with new facilities. Compact accelerator-based neutron sources under development are able to take up many of those activities. This paper paints the background for these developments, summarizes the replacement technologies, relates recent work that supports them, and alludes to some of the new activities that they enable.
Neutron beam performance of iBNCT as linac-based neutron source for boron neutron capture therapy
Authors: Kumada Hiroaki , Tanaka Susumu , Naito Fujio , Kurihara Toshikazu , Sugimura Takashi , Sakurai Hideyuki , Matsumura Akira , Sakae Takeji
Published: March 2020

The linac-based neutron source “iBNCT” developed by the Tsukuba team has been shown to generate a large intensity of neutrons. To confirm the applicability of the device to BNCT, several characteristic measurements have been implemented. In a water phantom experiment, when the accelerator was operated with an average current of 1.4 mA, the maximum thermal neutron flux was approximately 7.8 × 108 (cm-2s-1). From estimation of the stability of the linac, the results demonstrate its applicability to actual treatment.
The SONATE project, a French CANS for Materials Sciences Research
Authors: Ott Frédéric , Menelle Alain , Alba-Simionesco Christiane
Published: March 2020

We describe the Compact Accelerator-based Neutron Source SONATE which we are aiming for to replace the closed Orphée reactor at Saclay, France. The SONATE source would serve an instrumental suite of about 10 instruments. The instruments would be split into low resolution instruments and higher resolution instruments. Our reference design is based on a proton accelerator operating at an energy in the range 20-30 MeV. The accelerator would serve 2 target stations. The first one operating at 20Hz with 2ms long pulses serving low resolution instruments (SANS, reflectivity, imaging, spin-echo) and the second one operating at 100Hz, 200μs long pulses serving higher resolution instruments (powder diffraction, Direct Time-of-flight spectroscopy, Indirect geometry spectroscopy). The 2 operation modes would be interlaced. The peak current on the target is aimed at 100 mA with an average power on the target on the order of 50-80 kW. Numerical Monte-Carlo simulations show that we may expect instrument performances equivalent to the current instruments around Orphée or ISIS.
CoolGAL: a Galinstan bathed Be fast neutron production target at the NEPIR facility
Authors: Alfonso Barrera Rogelio , Bisello Dario , Esposito Juan , Mastinu Pierfrancesco , Prete Gianfranco , Silvestrin Luca , Wyss Jeffery
Published: March 2020

In this contribution, we present the CoolGAL fast neutron production target system, to be used in the initial phase of the NEPIR irradiation beamline at the SPES facility, that will be operational in 2022. Initially, NEPIR will be used for shielding studies against fast neutrons for space applications and to investigate neutron-induced single event effects in microelectronic devices and systems. In CoolGAL, the neutron production component, a thick Be cylinder, is immersed in a static bath of Galinstan, a liquid alloy of Ga, In and Sn, contained by an outer water cooled copper cladding. MCNPX calculations indicate that, by using a 1 μA current of 70 MeV protons, it can produce a fast neutron energy spectrum that is somewhat flat the 30-65 MeV energy range and with a sharp cut-off at the beam energy. At the standard test point, located 2.6 m downstream from the source, the beam spot diameter, defined by the peculiar collimation scheme of the initial phase of NEPIR, is 10 cm and the integral fast neutron flux is Φn(1< En<65 MeV) ~ 3×106 n cm-2s-1. Using proton beams with two different energies, one can calculate, by subtraction, the effects due to the neutrons in the energy interval defined by the two cut-off values. Preliminary results of ANSYS calculations, for a 1 μA proton current of 70 MeV protons (70 W), show a limited regime temperature (28 °C) of the Be component, capable of ensuring the exceptional safety level required for the operation at SPES. The thermal reliability of CoolGAL is very promising for future developments that require higher proton currents.
Energy and target material dependence of the neutron yield induced by proton and deuteron bombardment
Authors: Zakalek Paul , Doege Paul-Emmanuel , Baggemann Johannes , Mauerhofer Eric , Brückel Thomas
Published: March 2020

The neutron yield for compact accelerator driven neutron sources depends on the target material, the ion type and its energy. When such sources are operated with low energy proton beams below 30 MeV, typical target materials are lithium and beryllium. New developments indicate that higher energies or a deuteron beam might be useful to increase the neutron yield at constant accelerator power. Here we present the total neutron yield analytically calculated for protons and deuterons at energies up to 100 MeV for various target materials. The total neutron yield depends on the involved cross sections and the stopping power of the target material. This study shows that for energies lower than 30 MeV light target materials with a deuteron beam are preferable whereas for energies above 30 MeV heavy target materials show a high neutron yield with little difference for a proton or deuteron beam.
Low-dimensional moderators at ESS and compact neutron sources
Authors: Zanini Luca , Klinkby Esben , Mezei Ferenc , Takibayev Alan
Published: March 2020

Low-dimensional moderators were designed for the European Spallation Source (ESS), and the same concepts can be applied to compact sources. At ESS, quasi two-dimensional (2D) high-brightness moderators will serve all the instruments of the initial suite. The design of the moderators is influenced by several factors, such as the layout of the facility, the requirements for beam extraction, and the number of instruments; these constraints led to the choice of the 2D “butterfly” moderator for ESS. In an accelerator-based compact source, such moderators can be designed in an even more efficient way than for high-power sources, taking advantage of the lower heat loads and of the more compact arrangement of the target-moderator system, which gives more freedom in the optimization of the geometrical setup. Some promising design options have been explored.