bluuebunny/crossref_metadata_2025 huggingface dataset:
Statin therapy and recurrent venous thromboembolism in the elderly: a prospective cohort study
Authors: Kronenberg Regula Monika , Beglinger Shanthi , Stalder Odile , Méan Marie , Limacher Andreas , Beer Jürg Hans , Aujesky Drahomir , Rodondi Nicolas , Feller Martin
Published: October 2019

Previous studies reported lower rates of recurrent venous thromboembolism (rVTE) among statin users, but this association could be influenced by concurrent anticoagulation and confounding by statin indication. This study aimed to confirm the beneficial association between statins and rVTE, stratified according to periods with and without anticoagulation, and additionally employ propensity score weighted approach to reduce risk of confounding by indication. The setting was a prospective multicentre cohort study and the outcome was time to first rVTE in statin vs. non-statin users. 980 participants with acute VTE were enrolled (mean age 75.0 years, 47% women), with median follow-up of 2.5 years. Of 241 (24.3%) statin users, 21 (8.7%) suffered rVTE vs. 99 (13.4%) among 739 non-users. The overall adjusted sub-hazard ratio (aSHR) for rVTE comparing statin users to non-users was 0.72 (95%CI 0.44 to 1.19, p = 0.20). This association was only apparent during periods without anticoagulation (aSHR 0.50, 95%CI 0.27 to 0.92, p = 0.03; vs. with anticoagulation: aSHR 1.34, 95%CI 0.54 to 3.35, p = 0.53). Using propensity scores, the rVTE risk during periods without anticoagulation fell further (aSHR 0.20, 95%CI 0.08 to 0.49, p < 0.001). In conclusion, statin use is associated with a more pronounced risk reduction for rVTE than previously estimated, but only during periods without anticoagulation.
Tissue- and Species-Specific Patterns of RNA metabolism in Post-Mortem Mammalian Retina and Retinal Pigment Epithelium
Authors: Kallestad Les , Blackshaw Seth , Khalil Ahmad M. , Palczewski Krzysztof
Published: October 2019

Accurate analysis of gene expression in human tissues using RNA sequencing is dependent on the quality of source material. One major source of variation in mRNA quality is post-mortem time. While it is known that individual transcripts show differential post-mortem stability, few studies have directly and comprehensively analyzed mRNA stability following death, and in particular the extent to which tissue- and species-specific factors influence post-mortem mRNA stability are poorly understood. This knowledge is particularly important for ocular tissues studies, where tissues obtained post-mortem are frequently used for research or therapeutic applications. To directly investigate this question, we profiled mRNA levels in both neuroretina and retinal pigment epithelium (RPE) from mouse and baboon over a series of post-mortem intervals. We found substantial changes in gene expression as early as 15 minutes in the mouse and as early as three hours in the baboon eye tissues. Importantly, our findings demonstrate both tissue- and species- specific patterns of RNA metabolism, by identifying a set of genes that are either rapidly degraded or very stable in both species and/or tissues. Taken together, the data from this study lay the foundation for understanding RNA regulation post-mortem and provide novel insights into RNA metabolism in the tissues of the mammalian eye.
A Low-Power CMOS Microfluidic Pump Based on Travelling-Wave Electroosmosis for Diluted Serum Pumping
Authors: Yen Pei-Wen , Lin Shiang-Chi , Huang Yi-Chun , Huang Yu-Jie , Tung Yi-Chung , Lu Shey-Shi , Lin Chih-Ting
Published: October 2019

Microfluidic pump is an essential component in lab-on-chip applications. It is of importance to develop an active microfluidic pump with low-power and low-cost characteristics for portable and miniaturized diagnostic systems. Taking advantages of CMOS technologies, in this work, we report a low-power microfluidic pump based on travelling-wave electroosmosis (TWEO). Utilizing an integrated driving circuit, this monolithic CMOS microfluidic pump can be operated at 1.5 V driving voltage with a power consumption of 1.74 mW. The integrated driving circuit consist of a resistor-capacitor (RC) oscillator, a 90-degrees phase-shift square wave generator, and buffer amplifiers. Moreover, capabilities of the developed CMOS TWEO pump to drive diluted human serum are characterized. The flow rate of diluted human serum with dilution ratio of 1:1000 can achieve 51 μm/s. This is the first time demonstrating an in-situ CMOS-based microfluidic pump to drive the clinical diluted serum sample. As a consequence, this work demonstrates an essential component of CMOS biotechnologies for potential applications of portable in vitro diagnosis (IVD) systems.
Artificial two-dimensional polar metal by charge transfer to a ferroelectric insulator
Authors: Zhou W. X. , Wu H. J. , Zhou J. , Zeng S. W. , Li C. J. , Li M. S. , Guo R. , Xiao J. X. , Huang Z. , Lv W. M. , Han K. , Yang P. , Li C. G. , Lim Z. S. , Wang H. , Zhang Y. , Chua S. J. , Zeng K. Y. , Venkatesan T. , Chen J. S. , Feng Y. P. , Pennycook S. J. , Ariando A.
Published: October 2019

Integrating multiple properties in a single system is crucial for the continuous developments in electronic devices. However, some physical properties are mutually exclusive in nature. Here, we report the coexistence of two seemingly mutually exclusive properties-polarity and two-dimensional conductivity-in ferroelectric Ba0.2Sr0.8TiO3 thin films at the LaAlO3/Ba0.2Sr0.8TiO3 interface at room temperature. The polarity of a ∼3.2 nm Ba0.2Sr0.8TiO3 thin film is preserved with a two-dimensional mobile carrier density of ∼0.05 electron per unit cell. We show that the electronic reconstruction resulting from the competition between the built-in electric field of LaAlO3 and the polarization of Ba0.2Sr0.8TiO3 is responsible for this unusual two-dimensional conducting polar phase. The general concept of exploiting mutually exclusive properties at oxide interfaces via electronic reconstruction may be applicable to other strongly-correlated oxide interfaces, thus opening windows to new functional nanoscale materials for applications in novel nanoelectronics.
The first two examples of halogen bonding with a sigma hole-donating fluorine in the Csp3–F⋯Osp3interaction from polyfluorinatedtrans-dihalo-palladium(ii) di-substituted pyridine complexes
Authors: Elakkat Vijayanath , Chang Chu-Chun , Chen Jun-Yu , Fang Yung-Cheng , Shen Chia-Rui , Liu Ling-Kung , Lu Norman
Published: October 2019

Molecular packing diagram oftrans-[PdCl2(3-HCF2CF2CH2OCH2py)2] (left) showing a C8–F2⋯O1 halogen bond; (right) its stacking piles showing a herringbone pattern.
A facile oxidation–dehydration reaction-driven robust porous copper oxide nanobelt coating on copper foam for an energy-saving and low-cost urea oxidization reaction
Authors: Wang Yanqing , Li Yuemeng , Ding Liping , Ding Jun
Published: October 2019

A facile oxidation–dehydration reaction-driven robust porous copper oxide nanobelt coating on copper foam for an energy-saving and low-cost UOR.
Preparation and crystal structures of the beryllium ammines [Be(NH3)4]X2 (X = Br, I, CN, SCN, N3) and Be(NH3)2X'2 (X' = Cl, Br, I)
Authors: Müller Matthias , Buchner Magnus R.
Published: October 2019

Ammine complexes of beryllium halides and pseudo-halides have been synthesized through the reaction of metallic beryllium with ammonium salts in liquid ammonia or in the solid state.
Dyson orbitals within the fc-CVS-EOM-CCSD framework: theory and application to X-ray photoelectron spectroscopy of ground and excited states
Authors: Vidal Marta L. , Krylov Anna I. , Coriani Sonia
Published: October 2019

Ionization energies and Dyson orbitals within frozen-core core–valence separated equation-of-motion coupled cluster singles and doubles (fc-CVS-EOM-CCSD) enable efficient and reliable calculations of standard XPS and of UV-pump/XPS probe spectra.
Intrinsic and extrinsic effects on the electrotoroidic switching in a ferroelectric notched nanodot by a homogeneous electric field
Authors: Dinh-Van Hai , Lich Le Van , Bui Tinh Quoc , Le Tuan Van , Nguyen Trong-Giang , Shimada Takahiro , Kitamura Takayuki
Published: October 2019

Control of polarization vortex switching in a ferroelectric notched nanodot by a homogeneous electric field under intrinsic and extrinsic effects.
Two-dimensional ZrB2C2 with multiple tunable Dirac states
Authors: Zhang Bingwen , Li Yuliang , Zhang Cheng , Wang Jun
Published: October 2019

In this paper, we designed a two-dimensional honeycomb monolayer ZrB2C2, which is predicted to be a stable nanosheet and exhibits favorable mechanical and thermal properties.
Adducts of triangular silver(i) 3,5-bis(trifluoromethyl)pyrazolate with thiophene derivatives: a weak interaction model of desulfurization
Authors: Liu Rongrong , Zhang Wenhua , Wei Donghui , Chen Jing-Huo , Ng Seik Weng , Yang Guang
Published: October 2019

Triangular silver(i) 3,5-bis(trifluoromethyl)pyrazolate (Ag3pz3) can quickly sequester dibenzothiophene (DBT) in isooctane, forming insoluble 1 : 1 adduct and thus possessing potential use in desulfurization technology.
Isomeric Ir(iii) complexes for tracking mitochondrial pH fluctuations and inducing mitochondrial dysfunction during photodynamic therapy
Authors: Chen Haijie , Ge Chen , Cao Huiqun , Zhang Xuepeng , Zhang Ling , Jiang Linhai , Zhang Pingyu , Zhang Qianling
Published: October 2019

Two pairs of isomeric phosphorescent Ir(iii) complexes that show mitochondrial pH-response and induce mitochondrial dysfunction during photodynamic therapy.
The large piezoelectricity and high power density of a 3D-printed multilayer copolymer in a rugby ball-structured mechanical energy harvester
Authors: Yuan Xiaoting , Gao Xiangyu , Yang Jikun , Shen Xinyi , Li Zhanmiao , You Sujian , Wang Zehuan , Dong Shuxiang
Published: October 2019

A 3D-printed multilayer copolymer rugby ball-structured energy harvester is prepared, and a high peak output power of 16.4 mW cm−2 is obtained.
Short-term exposure to low concentrations of copper oxide nanoparticles can negatively impact the ecological performance of a cosmopolitan freshwater fungus
Authors: Seena Sahadevan , Kumar Santosh
Published: October 2019

Short term exposure to very low concentrations of CuO NPs can have an impact on freshwater ecological processes.
Metabonomics-assisted label-free quantitative proteomic and transcriptomic analysis reveals novel insights into the antifungal effect of graphene oxide for controllingFusarium graminearum
Authors: Wang Xiuping , Liu Caixiang , Li Hongqiang , Zhang Haitao , Ma Ruijing , Zhang Qinwen , Yang Fang , Liao Yu-cai , Yuan Wenya , Chen Fangfang
Published: October 2019

Graphene oxide (GO), which has been emerging as a novel antimicrobial agent against plant pathogens, has aroused great research interest and is considered as highly promising in agricultural science.
In vivoformed metabolites of polyphenols and their biological efficacy
Authors: Serreli Gabriele , Deiana Monica
Published: October 2019

The metabolites of polyphenols are antioxidant, anti-inflammatory and anticancer agents. Being bioavailable, they may play an important role in preventing degenerative diseases.
A sustainable sulfur–carbonaceous composite electrode toward high specific energy rechargeable cells
Authors: Hwa Yoon , Kim Hyo Won , Shen Hao , Parkinson Dilworth Y. , McCloskey Bryan D. , Cairns Elton J.
Published: October 2019

A (calculated) high specific energy of 325 W h kg−1 is achieved via a rational design of a sulfur–carbonaceous composite electrode.
Trehalose alleviates cadmium-induced brain damage by ameliorating oxidative stress, autophagy inhibition, and apoptosis
Authors: Tang Kou-Kou , Liu Xin-Yu , Wang Zhen-Yong , Qu Kui-Chao , Fan Rui-Feng
Published: October 2019

Tre antagonizes Cd-induced brain injury by suppressing oxidative stress and autophagy inhibition, ultimately inhibiting apoptosis. Especially, persistent activation of Nrf2 contributes to tissue damage, rather than playing an active protective role.
Role of chemical interface damping for tuning chemical enhancement in resonance surface-enhanced Raman scattering of plasmonic gold nanorods
Authors: Seo Min Jung , Kim Geun Wan , Tsalu Philippe Vuka , Moon Seong Woo , Ha Ji Won
Published: October 2019

Chemical interface damping in plasmonic gold nanoparticles is closely connected with chemical enhancement in resonance SERS.
V(v)-Schiff base species induce adipogenesis through structure-specific influence of genetic targets
Authors: Tsave O. , Halevas E. , Yavropoulou M. P. , Yovos E. , Hatzidimitriou A. , Psycharis V. , Ypsilantis K. , Stathi P. , Salifoglou A.
Published: October 2019

Appropriately designed Schiff-base substrates enhance V(v)-bioavailability and insulin-mimetic biomolecular gene profiling, inducing adipogenesis in a structure-specific manner.
Well-defined Pd anchoring on the surface of porous ZnO nanocomposites with excellent photocatalytic activity and good reusability for the removal of phenol from water
Authors: Peng Si-Yan , Yang Liusai , Yu Leshu , Li Xiao-Yun , Zhou Yuan-Zhen , Lv Yingying , Zhu Feng
Published: October 2019

Well-defined Pd/ZnO nanocomposites prepared by modifying ZnO nanosheets with Pd nanoparticles exhibit excellent photocatalytic activity and good reusability for the removal of phenol from water.
A magnetic activated sludge for Cu(ii) and Cd(ii) removal: adsorption performance and mechanism studies
Authors: Liu Yingrui , Yang Qingwei , Feng Rui , Xu Weiying , Yan Liangguo , Du Bin , Wei Qin , Wei Dong
Published: October 2019

In the present study, a novel magnetic activated sludge (MAS) was successfully synthesized and applied for heavy metal removal.
In situ construction of WO3/g-C3N4 composite photocatalyst with 2D–2D heterostructure for enhanced visible light photocatalytic performance
Authors: Zhuang Huaqiang , Cai Zhenping , Xu Wentao , Huang Mianli , Liu Xiaobin
Published: October 2019

A WO3/g-C3N4 composite photocatalyst with 2D–2D heterostructure was designed and constructed by an in situ preparation strategy.
Investigation of catalytic activity and mechanism for RhB degradation by LaMnO3perovskites preparedviathe citric acid method
Authors: Guo Jiaxiu , Zhou Houren , Ting Shen , Luo Hongdi , Liang Juan , Yuan Shandong
Published: October 2019

LaMnO3exhibits an excellent degradation ability of RhB under highly acidic conditions without adding additional oxidants or light irradiation.
Camptothecin-based dendrimersomes for gene delivery and redox-responsive drug delivery to cancer cells
Authors: Laskar Partha , Somani Sukrut , Campbell Sara Jane , Mullin Margaret , Keating Patricia , Tate Rothwelle J. , Irving Craig , Leung Hing Y. , Dufès Christine
Published: October 2019

Schematic illustration of camptothecin-based dendrimersomes for DNA delivery and redox-responsive camptothecin release to cancer cells.
Novel orange-yellow-green color-tunable Bi3+-doped Ba3Y4−wLuwO9 (0 ≤ w ≤ 4) luminescent materials: site migration and photoluminescence control
Authors: Xing Gongcheng , Gao Zhiyu , Tao Mengxuan , Wei Yi , Liu Yixin , Dang Peipei , Li Guogang , Lin Jun
Published: October 2019

The site migration of Bi3+ induced orange-yellow-green photoluminescence control in Ba3Y4−wLuwO9 (0 ≤ w ≤ 4).
An ionophore-based persistent luminescent ‘Glow Sensor’ for sodium detection
Authors: Ferris Mark S. , Behr Madeline R. , Cash Kevin J.
Published: October 2019

A sodium-selective bulk-optode sensor is created by coupling persistent luminescence microparticles with a pH-sensitive dye through an ionophore-based detection mechanism.
A rapid on-site analysis method for the simultaneous extraction and determination of Pb2+ and Cd2+ in cereals
Authors: Zhou Ming-hui , Tian Wei , Zhang Jie-qiong , Chen Xi , Wu Yan-xiang , Wang Song-xue
Published: October 2019

To achieve rapid on-site screening rapid pretreatment for the determination of Pb2+ and Cd2+ in cereals by a portable electrochemical analyzer with disposable screen-printed electrodes, a new reliable and simple extraction method for Pb2+ and Cd2+ was developed.
Experimental study of growth kinetics of CO2 hydrates and multiphase flow properties of slurries in high pressure flow systems
Authors: Lv Xiao-fang , Zuo Jiang-wei , Liu Yang , Zhou Shi-Dong , Lu Da-yong , Yan Ke-le , Shi Bo-hui , Zhao Hui-jun
Published: October 2019

The formation and accumulation of hydrates in high pressure oil and gas pipelines bring great risks to field development and deep-water transportation.
Comparative investigation of interactions of hydrogen, halogen and tetrel bond donors with electron-rich and electron-deficient π-systems
Authors: Ibrahim Mahmoud A. A. , Ahmed Ossama A. M. , Moussa Nayra A. M. , El-Taher Sabry , Moustafa Hussien
Published: October 2019

Three seminal types of noncovalent interaction, namely: hydrogen, halogen and tetrel interactions with π-systems, were investigated using quantum mechanical calculations.
High-performance rechargeable zinc-based dual-ion batteries
Authors: Ji Bifa , Yao Wenjiao , Tang Yongbing
Published: October 2019

All the reported two kinds of nonaqueous zinc-based battery systems present good electrochemical performance and have good potential for large-scale energy storage with good safety and environmental friendliness.
Orientationally engineered 2D/3D perovskite for high efficiency solar cells
Authors: Abbas Muhammad Sohail , Hussain Sabir , Zhang Jinaqi , Wang Boxin , Yang Chen , Wang Zhen , Wei Zhixiang , Ahmad Rashid
Published: October 2019

A 2D–3D perovskite, in which 3D perovskite phase is bridged by 2D perovskite having periodically repeated vertical orientation is reported. It's PCE and stability is better than 3D MAPbI3 and it is an excellent structural strategy to improve stability of perovskite solar cells.
Ultra-stable CsPbBr3 nanocrystals with near-unity photoluminescence quantum yield via postsynthetic surface engineering
Authors: Zu Yanqing , Dai Jinfei , Li Lu , Yuan Fang , Chen Xiang , Feng Zhicun , Li Kun , Song Xiaojuan , Yun Feng , Yu Yue , Jiao Bo , Dong Hua , Hou Xun , Ju Minggang , Wu Zhaoxin
Published: October 2019

ADA + ZnBr2 passivated CsPbBr3 nanocrystals possess high photoluminescence quantum yield and good stability before and after storage for 65 days.
Construction of a thiourea-based metal–organic framework with open Ag+ sites for the separation of propene/propane mixtures
Authors: Chang Zhiduo , Lin Rui-Biao , Ye Yingxiang , Duan Chunying , Chen Banglin
Published: October 2019

A thiourea-based metal–organic framework with open Ag+ sites for the separation of a C3H6/C3H8 mixture.
Binder-free carbon nano-network wrapped carbon felt with optimized heteroatom doping for vanadium redox flow batteries
Authors: Zhang Xiangyang , Wu Qixing , Lv Yunhui , Li Yongliang , Zhou Xuelong
Published: October 2019

Carbon nano-network wrapped carbon felt was proposed to promote the advection–diffusion–reaction process of vanadium redox flow batteries.
Emerging nanostructured carbon-based non-precious metal electrocatalysts for selective electrochemical CO2 reduction to CO
Authors: Wang Xinyue , Zhao Qidong , Yang Bin , Li Zhongjian , Bo Zheng , Lam Kwok Ho , Adli Nadia Mohd , Lei Lecheng , Wen Zhenhai , Wu Gang , Hou Yang
Published: October 2019

An overview of different synthetic methods of Nano-CNMs and the relationships between their structure/composition–performance for CO production via ECR is presented.
Carrier-free self-built aspirin nanorods as anti-aggregation agents towards alpha-crystallin-derived peptide aggregates: potential implications in non-invasive cataract therapy
Authors: Bisht Anjali , Sharma Manju , Sharma Shikha , Ali Md. Ehesan , Panda Jiban Jyoti
Published: October 2019

Carrier free self-built aspirin nanorods as anti-aggregating agents for model crystallin peptides.
Topographical patterning: characteristics of current processing techniques, controllable effects on material properties and co-cultured cell fate, updated applications in tissue engineering, and improvement strategies
Authors: Zhang Ke , Xiao Xiongfu , Wang Xiumei , Fan Yubo , Li Xiaoming
Published: October 2019

Topographical patterning has recently attracted lots of attention in regulating cell fate, understanding the mechanism of cell–microenvironment interactions, and solving the great issues of regenerative medicine.
Tuning the luminescence of Ca9La(PO4)7:Eu2+via artificially inducing potential luminescence centers
Authors: Li Xiaotong , Li Panlai , Liu Chunjiao , Zhang Li , Dai Danjie , Xing Zhenhua , Yang Zhiping , Wang Zhijun
Published: October 2019

Using divalent alkaline earth metal ions as inducers, new luminescence centers were obtained by manual intervention, thus achieving great enrichment and controllable adjustment of the spectrum.
Discovery of a nitrogen-enhanced mildly metal-poor binary system: Possible evidence for pollution from an extinct AGB star
Authors: Fernández-Trincado José G. , Mennickent Ronald , Cabezas Mauricio , Zamora Olga , Martell Sarah L. , Beers Timothy C. , Placco Vinicius M. , Nataf David M. , Mészáros Szabolcs , Minniti Dante , Schleicher Dominik R. G. , Tang Baitian , Pérez-Villegas Angeles , Robin Annie C. , Reylé Céline
Published: October 2019

We report the serendipitous discovery of a nitrogen-rich, mildly metal-poor ([Fe/H] = −1.08) giant star in a single-lined spectroscopic binary system found in the SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE-2) survey, Data Release 14 (DR14). Previous work has assumed that two percent of halo giants with unusual elemental abundances have been evaporated from globular clusters, but other origins for their abundance signatures, including binary mass transfer, must also be explored. We present the results of an abundance reanalysis of the APOGEE-2 high-resolution near-infrared spectrum of 2M12451043+1217401 with the Brussels Automatic Stellar Parameter (BACCHUS) automated spectral analysis code. We manually re-derive the main element families, namely light elements (C, N), elements (O, Mg, Si), the iron-peak element (Fe), s-process element (Ce), and light odd-Z element (Al). Our analysis confirms the N-rich nature of 2M12451043+1217401, which has a [N/Fe] ratio of +0.69, and shows that the abundances of C and Al are slightly discrepant from those of a typical mildly metal-poor red giant branch star, but exhibit Mg, Si, O and s-process abundances (Ce) of typical field stars. We also detect a particularly large variability in the radial velocity of this star over the period of the APOGEE-2 observations; the most likely orbit fit to the radial velocity data has a period of 730.89  ±  106.86 days, a velocity semi-amplitude of 9.92  ±  0.14 km s−1, and an eccentricity of ∼0.1276  ±  0.1174. These data support the hypothesis of a binary companion, which has probably been polluted by a now-extinct asymptotic giant branch star.
Cosmic voids in modified gravity scenarios
Authors: Perico Eder L. D. , Voivodic Rodrigo , Lima Marcos , Mota David F.
Published: October 2019

Modified gravity (MG) theories aim to reproduce the observed acceleration of the Universe by reducing the dark sector while simultaneously recovering General Relativity (GR) within dense environments. Void studies appear to be a suitable scenario to search for imprints of alternative gravity models on cosmological scales. Voids cover an interesting range of density scales where screening mechanisms fade out, which reaches from a density contrast δ ≈ −1 close to their centers to δ ≈ 0 close to their boundaries. We present an analysis of the level of distinction between GR and two modified gravity theories, the Hu–Sawicki f(R) and the symmetron theory. This study relies on the abundance, linear bias, and density profile of voids detected in N-body cosmological simulations. We define voids as connected regions made up of the union of spheres with a mean density given by ρ̅v = 0.2 ρ̅m, but disconnected from any other voids. We find that the height of void walls is considerably affected by the gravitational theory, such that it increases for stronger gravity modifications. Finally, we show that at the level of dark matter N-body simulations, our constraints allow us to distinguish between GR and MG models with |fR0| > 10−6 and zSSB >  1. Differences of best-fit values for MG parameters that are derived independently from multiple void probes may indicate an incorrect MG model. This serves as an important consistency check.
TESS first look at evolved compact pulsators
Authors: Bell Keaton J. , Córsico Alejandro H. , Bischoff-Kim Agnès , Althaus Leandro G. , Bradley Paul A. , Calcaferro Leila M. , Montgomery Michael H. , Uzundag Murat , Baran Andrzej S. , Bognár Zsófia , Charpinet Stéphane , Ghasemi Hamed , Hermes J. J.
Published: October 2019

Context.Pulsation frequencies reveal the interior structures of white dwarf stars, shedding light on the properties of these compact objects that represent the final evolutionary stage of most stars. Two-minute cadence photometry from the Transiting Exoplanet Survey Satellite (TESS) records pulsation signatures from bright white dwarfs over the entire sky.

Aims.As part of a series of first-light papers from TESS Asteroseismic Science Consortium Working Group 8, we aim to demonstrate the sensitivity of TESS data, by measuring pulsations of helium-atmosphere white dwarfs in the DBV instability strip, and what asteroseismic analysis of these measurements can reveal about their stellar structures. We present a case study of the pulsating DBV WD 0158−160 that was observed as TIC 257459955 with the two-minute cadence for 20.3 days in TESS Sector 3.

Methods.We measured the frequencies of variability of TIC 257459955 with an iterative periodogram and prewhitening procedure. The measured frequencies were compared to calculations from two sets of white dwarf models to constrain the stellar parameters: the fully evolutionary models fromLPCODEand the structural models fromWDEC.

Results.We detected and measured the frequencies of nine pulsation modes and eleven combination frequencies of WD 0158−160 to ∼0.01 μHz precision. Most, if not all, of the observed pulsations belong to an incomplete sequence of dipole (ℓ = 1) modes with a mean period spacing of 38.1 ± 1.0 s. The global best-fit seismic models from bothLPCODEandWDEChave effective temperatures that are ≳3000 K hotter than archival spectroscopic values of 24 100–25 500 K; however, cooler secondary solutions are found that are consistent with both the spectroscopic effective temperature and distance constraints fromGaiaastrometry.

Conclusions.Our results demonstrate the value of the TESS data for DBV white dwarf asteroseismology. The extent of the short-cadence photometry enables reliably accurate and extremely precise pulsation frequency measurements. Similar subsets of both theLPCODEandWDECmodels show good agreement with these measurements, supporting that the asteroseismic interpretation of DBV observations from TESS is not dominated by the set of models used. However, given the sensitivity of the observed set of pulsation modes to the stellar structure, external constraints from spectroscopy and/or astrometry are needed to identify the best seismic solutions.
PreProFit: Pressure Profile Fitter for galaxy clusters
Authors: Castagna Fabio , Andreon Stefano
Published: October 2019

Galaxy cluster analyses based on high-resolution observations of the Sunyaev–Zeldovich (SZ) effect have become common in the last decade. We presentPreProFit, the first publicly available code designed to fit the pressure profile of galaxy clusters from SZ data.PreProFitis based on a Bayesian forward-modelling approach, allows the analysis of data coming from different sources, adopts a flexible parametrization for the pressure profile, and fits the model to the data accounting for Abel integral, beam smearing, and transfer function filtering.PreProFitis computationally efficient, is extensively documented, has been released as an open source Python project, and was developed to be part of a joint analysis of X-ray and SZ data on galaxy clusters.PreProFitreturnsχ2, model parameters and uncertainties, marginal and joint probability contours, diagnostic plots, and surface brightness radial profiles.PreProFitalso allows the use of analytic approximations for the beam and transfer functions useful for feasibility studies.
Planet and star synergy at high-spectral resolution. A rationale for the characterization of exoplanet atmospheres
Authors: Chiavassa A. , Brogi M.
Published: October 2019

Context. Spectroscopy of exoplanet atmospheres at high-resolving powers is rapidly gaining popularity for measuring the presence of atomic and molecular species. While this technique is particularly robust against contaminant absorption in the Earth’s atmosphere, the non-stationary stellar spectrum, in the form of either Doppler shift or distortion of the line profile during planetary transits, creates a non-negligible source of noise that can alter or even prevent detection.

Aims. Our aim was to use state-of-the art three-dimensional stellar simulations to directly remove the signature of the star from observations prior to cross correlation with templates for the planet’s atmosphere, which are commonly used to extract the faint exoplanet signal from noisy data.

Methods. We computed synthetic spectra from 3D simulations of stellar convection resolved both spatially and temporally, and we coupled them with an analytical model reproducing the correct geometry of a transiting exoplanet. We applied the method to the early K-dwarf, HD 189733, and re-analyzed transmission and emission spectroscopy of its hosted exoplanet. In addition, we also analyzed emission spectroscopy of the non transiting exoplanet 51 Pegasi b, orbiting a solar-type star.

Results. We find a significant improvement in planet detectability when removing the stellar spectrum with our method. In all cases, we show that the method is superior to a simple parametrisation of the stellar line profile or to the use of 1D stellar models. We show that this is due to the intrinsic treatment of convection in 3D simulations, which allows us to correctly reproduce asymmetric and blue-shifted spectral lines, and intrinsically model center-to-limb variation and Rossiter-McLaughlin effect potentially altering the interpretation of exoplanet transmission spectra. In the case of 51 Pegasi b, we succeed in confirming a previous tentative detection of the planet’s K-band spectrum due to the improved suppression of stellar residuals.

Conclusions. Future high-resolution observations will benefit from the synergy with stellar spectroscopy and can be used to test the correct modeling of physical processes in stellar atmospheres. We highlight key improvements in modeling techniques and knowledge of opacity sources to extend this work to shorter wavelengths and later-type stars.
Biological peculiarities and characteristics of Erodium tataricum WILLD. cenopopulation in Khakasia
Authors: Barsukova Irina , Leonova Tatiana
Published: October 2019

Biological and structural peculiarities of Erodium tataricum Willd. cenopopulations in natural surroundings of Khakasia are examined. It is found out that the species make two vegetal forms under the changing environmental conditions. Ontogeny is complete, regeneration does not take place. Two types of ontogeny are found out: morphological and dynamic (according to the rate of growth). Examined Erodium tataricum Willd. cenopopulations are normal and incomplete. They are characterized by left-sided and bimodal ontogenetic spectra.
On the validation of spatial statistical vegetation models
Authors: Makhatkov Igor
Published: October 2019

The features of coefficients of determination and coefficients of leave-one-out method for spatial vegetation model and spatial models of squared deviations are discussed. The properties of models are illustrated in key area for spatial model of Cladonia stellaris projective cover.
Standard flora as a standard quantitative evaluation of vascular plant diversity of terrestrial ecosystems
Authors: Nikolin Evgenii G.
Published: October 2019

A new method of accounting for the diversity of vascular plants in the reference area of standard flora, covering an area of 1 sq. km, has been tested in the basins of the Lena and Indigirka rivers. Quantitative indices of the diversity of 3 standard floras in different latitudinal and altitudinal ranges of North-East Asia are presented.
The lichens of the plant communities in the middle reaches of the Uty River Valley
Authors: Sagalakova Alena , Zyryanova Olga , Larina Mariya
Published: October 2019

The article presents the data on the species communities situated in the middle reaches of the Uty river valley (Beisky District, Republic of Khakassia). The taxonomic list of lichens is represented by 51 taxa of a species rank belonging to 24 genera and 11 families. The largest number of species is characterized by the crustose life form. Mesophytes and epiphytes are predominant in the terms of ecological substrate.
The influence of willow plantations and soil composition on the process of natural vegetation settlement at oil drilling sites in Western Siberia
Authors: Sedykh Vladimir N. , Tarakanov Vyacheslav V. , Telyatnikov Mikhail Yu.
Published: October 2019

Test cultures of various willow species were created in 1997 on a technogenic sandy site of one of oil deposits (62°46’18.36" N, 72°09’48.69" E). Sixty-five isolated plots, including various soil substrates (sand, peat, drilling wastes), were placed in the testing area of 684 m2. Optimum combinations of substrate components were identified, and the tolerance of willow species to drilling wastes was revealed by the results of investigating 1-5-year cultures [1]. In 2016 we investigated the natural settlement of aborigine plants in this test plot. The willow cultures mortality was high according to short offspring vegetative lifetimes and the limitation of feed areas. However, willow cultures and soil reclamation stimulated a settlement of natural plant seedlings. The comparison of phytocenoses, which were formed in various experimental and "background" conditions, has allowed making some conclusions. 44 plant species are growing now in the experimental area. The least number of species is characteristic for pure sand and pure peat substrates, the greatest − for complex substrates with sand, peat and drilling wastes. Thus, the experimental willow cultures and partial soil reclamation accelerated the formation process of forest ecosystems that created a "plant oasis" on a deserted landscape of technogenic sand.
Materials on the distribution of plant species which are rare for the Volgograd oblast
Authors: Senator Stepan , Vasjukov Vladimir , Zibzeev Eugene , Korolyuk Andrey
Published: October 2019

The information about the distribution of 28 rare and endangered species of vascular plants under Federal and regional security, registered in 2018 on the territory of the Volgograd oblast under the Federal and regional security is given. Among them, 2 species (Crambe tataria Sebeok и Stipa zalesskii Wilensky ex P. A. Smirn.) are included in the List of Threatened plant species of Europe. Each location is linked to the grid of Atlas Flora Europaea. The obtained materials about the distribution of rare and endangered species of vascular plants represent an important data for long-term monitoring and also for environmental management measures at the regional level.
Various methods for isolating DNA from fruiting bodies on the example of Pleurotus pulmonarius (higher basidiomycetes) of the Novosibirsk Region for barcoding of edible and medicinal mushrooms
Authors: Vlasenko Vyacheslav , Asbaganov Sergey , Vlasenko Anastasia
Published: October 2019

We conducted experiments to increase the concentration of extracted DNA from the fruiting bodies of this species using various lysis buffers and extraction time. In general, DNA isolation according to the protocol using SDS made it possible to obtain higher concentrations thereof, as in the case of increasing the extraction time from 1 to 24 hours and using additional purification with chloroform.
State Estimation and Determination of Flexibility Potential in Medium Voltage Networks*
Authors: Rewald Florian , Pohl Oliver , Häger Ulf , Rehtanz Christian
Published: October 2019

This paper describes how flexibility of medium voltage systems can be used for operation of high voltage systems. This is explained using the example of a congestion management system for high voltage networks developed in the research project IDEAL. First, it is explained to what extent flexibility is required for high voltage system operation. After that, the entire congestion management system with flexibility of medium voltage systems is presented. Then, methodology for observability analysis, state estimation and determination of flexibility potential is shown. Finally, the implementation of the methodology in two real medium voltage systems is described.
Deep Reinforcement Learning for Energy Microgrids Management Considering Flexible Energy Sources
Authors: Tomin Nikita , Zhukov Alexey , Domyshev Alexander
Published: October 2019

The problem of optimally activating the flexible energy sources (short- and long-term storage capacities) of electricity microgrid is formulated as a sequential decision making problem under uncertainty where, at every time-step, the uncertainty comes from the lack of knowledge about future electricity consumption and weather dependent PV production. This paper proposes to address this problem using deep reinforcement learning. To this purpose, a specific deep learning architecture has been used in order to extract knowledge from past consumption and production time series as well as any available forecasts. The approach is empirically illustrated in the case of off-grid microgrids located in Belgium and Russia.
Flexibility Enhancement in an Islanded Distribution Power System by Online Demand-Side Management
Authors: Chulyukova Margarita , Voropai Nikolai
Published: October 2019

The paper considers the possibilities of increasing the flexibility of power distribution systems by real-time load management. The principles of the implementation of special automatic systems for this purpose are proposed. These systems enable some loads of specific consumers of the power distribution system switched to islanded operation to “shift” from the daily maximum to the minimum, which makes some generators available to connect certain essential consumers disconnected earlier by under-frequency load shedding system to the power system. The approach under consideration is illustrated by a power system with distributed generation.
Hybrid approximations for fractional calculus
Authors: Razzaghi Mohsen
Published: October 2019

In this paper, a numerical method for solving the fractional differential equations is presented. The method is based upon hybrid functions approximation. The properties of hybrid functions consisting ofblock-pulse functions and Taylor polynomials are presented. The Riemann-Liouville fractional integral operator for hybrid functions is given. This operator is then utilized to reduce the solution of the initial value problems for fractional differential equations to a system of algebraic equations. Illustrative examples are included to demonstrate the validity and applicability of the technique.
On the symmetrized S-divergence
Authors: Simić Slavko
Published: October 2019

In this paper we worked with the relative divergence of type s, s ∈ ℝ, which include Kullback-Leibler divergence and the Hellinger and χ2 distances as particular cases. We give here a study of the sym- metrized divergences in additive and multiplicative forms. Some ba-sic properties as symmetry, monotonicity and log-convexity are estab-lished. An important result from the Convexity Theory is also proved.
A high order immersed finite element method for parabolic interface problems
Authors: Jones Derrick , Zhang Xu
Published: October 2019

We present a high order immersed finite element (IFE) method for solving 1D parabolic interface problems. These methods allow the solution mesh to be independent of the interface. Time marching schemes including Backward-Eulerand Crank-Nicolson methods are implemented to fully discretize the system. Numerical examples are provided to test the performance of our numerical schemes.
Approximate solutions for the Bagley-Torvik fractional equation with boundary conditions using the Polynomial Least Squares Method
Authors: Pasca Madalina Sofia , Razzaghi Mohsen , Lapadat Maria
Published: October 2019

In this paper we apply the recently introduced Polynomial Least Squares Method (PLSM) to compute approximate analyticalpolynomial solutions for the Bagley-Torvik fractional equation with boundary conditions.

The Bagley—Torvik equation may be used to model the motion of real physical systems such as the motion of a thin rigid plate immersed in a Newtonian fluid. In order to emphasize the accuracy of PLSM, we included a comparison with previous approximate solutions obtained for the Bagley-Torvik fractional equation by means of other approximation method.
A new analytical approach to investigate human gait dynamics
Authors: Mihut Denisa , Herisanu Nicolae
Published: October 2019

In this paper we propose a new analytical approach to the study of human gait dynamics. A new and reliable method, namely the Optimal Auxiliary Functions Method (OAFM) is employed to obtain explicit and accurate analytical solutions. The capabilities of this new method are successfully tested in the studyof human gait dynamics and an excellent agreement between analytical and numerical solutions is demonstrated. The accuracy of the analytical results is assured by the so-called convergence-control parameters, whose optimal values are rigorously identified in order to provide a fast convergence to the exact solution.
Plastic deformation simulation of steel panels
Authors: Savin Mihaela , Presura Adrian , Chirica Ionel
Published: October 2019

This paper presents the FEM analysis of plastic deformation of different steel panels using a spherical indenter. Two experiments were done: first on a simple steel panel and second on a stiffened steel panel, which were subjected to a static plastic deformation produced with help of a spherical indenter. The results of the practical test were compared with the results of numerical simulations, which were accomplished using ANSYS-Static Structural module.

The tests were realized using an experimental stand based on a screw press mechanism. The tests consist in vertical displacement of the spherical bulb, which in this way deformed the panel leaning on the stand frame. During the tests were measured the force applied to the indenter, with help of an PLC500 force transducer, and the vertical displacement of the panel in the application point of force, with help of an HBM WA/300 displacement transducer.

The results of calculations are presented below as: final deformed models and force-displacement diagrams with the comparison between experiment and numerical simulation.

In conclusion of this research the compared results between the experiments and numerical simulations revealed that can be achieved accurate results using FEM analysis for plastic deformation problems, with proper parameters settings.
Air pollution monitoring with secure low-cost Vehicular Sensor Networks
Authors: KolumbÁn-Antal György , Lasak Vladko , Bogdan Razvan , Groza Bogdan
Published: October 2019

Counteracting the effects of air quality degradation is one of the main challenges in large cities today. To achieve such a goal, the first step is to control the emissions of various pollutant gases which in turn requires their concentrations to be measured such that proper methods can be applied. In this work we present a low cost urban air pollution monitoring system which we developed as proof-of-concept in Timisoara, Romania. The proposed solution is a Vehicular Sensor Network (VSN), with affordable midclass sensor nodes being installed on moving vehicles, ideally on the public transportation busses. The system measures temperature, humidity, the concentration of CO2 and dust, along with Volatile Organic Compounds (VOC). The aim of collecting weather data is to build correlations between air pollution levels and different weather conditions. In addition to technical constraints for measuring air quality, one of the challenges that we address is to implement secure transmissions between the devices. This raises several difficulties on microcontrollers that we use due to their low memory and computational resources. To answer both privacy and security issues, the proposed data transmission protocol of the measuring system, builds upon a modified version of the Station to Station (STS) protocol which allows secure tunnelling in an anonymous manner.
Energy harvesting with piezoelectric materials for IoT – Review
Authors: Covaci Corina , Gontean Aurel
Published: October 2019

The goal of this paper is to review up to date energy harvesting techniques, while focusing on energy harvesting with piezoelectric materials. A classification of various energy harvesting sources is provided in order to properly locate piezoelectricity. Piezoelectric energy harvesting uses the special material property that exists in many single crystalline materials: the direct piezoelectric effect. Those materials are generating electric potential when mechanical stress is applied. There are two types of mechanical stress suitable for piezoelectric energy harvesting: hitting and vibrating. The hitting method involves the direct transfer of energy to piezoelectric modules, so it generates more power than the vibrating method. This kind of energy harvesting is used to drive low energy consuming devices and is suitable for applications where replacement of battery or maintenance is unpractical, like sensors in the human body, for powering portable devices or it can be used for improvement of a smart building concept. If the piezoelectric transducers are placed in the floor of a crowded area or in shoes, it can theoretically generate 4.9 J/Step; therefore, this energy can be used to replace the chargeable batteries. This review is useful for a proper positioning of this type in the IoT broad context and mainly as an alternate energy source for wearables.
A Nitsche-based formulation for fluid-structure interactions with contact
Authors: Burman Erik , Fernández Miguel A. , Frei Stefan
Published: October 2019

We derive a Nitsche-based formulation for fluid-structure interaction (FSI) problems with contact. The approach is based on the work of Chouly and Hild (SIAM J. Numer. Anal.51(2013) 1295–1307) for contact problems in solid mechanics. We present two numerical approaches, both of them formulating the FSI interface and the contact conditions simultaneously in equation form on a joint interface-contact surface Γ(t). The first approach uses a relaxation of the contact conditions to allow for a small mesh-dependent gap between solid and wall. The second alternative introduces an artificial fluid below the contact surface. The resulting systems of equations can be included in a consistent fashion within a monolithic variational formulation, which prevents the so-called “chattering” phenomenon. To deal with the topology changes in the fluid domain at the time of impact, we use a fully Eulerian approach for the FSI problem. We compare the effect of slip and no-slip interface conditions and study the performance of the method by means of numerical examples.
Formation of an Innovative and Creative System of Managing the Development of Industrial Enterprises
Authors: Chobitok Viktoriia , Chumak Larisa , Demyanenko Tetiana , Us Yulia
Published: October 2019

The article deals with the issues of forming an innovative and creative system of managing the development of industrial enterprises. An analysis of the state of the development of domestic enterprises has been carried out. The essence of the directions of the development of domestic industrial enterprises has been defined. The analysis of the essence of the concept of “enterprise development” has been conducted, with the authors’ own definition of the term being provided. Theoretical bases for the formation of the concept of “an innovative and creative system of managing the development of industrial enterprises” have been devised. Types of innovative and creative directions of managing the development of industrial enterprises have been singled out.