bluuebunny/crossref_metadata_2025 huggingface dataset:
Metal-catalysed selective transfer hydrogenation of α,β-unsaturated carbonyl compounds to allylic alcohols
Authors: Farrar-Tobar Ronald A. , Dell'Acqua Andrea , Tin Sergey , de Vries Johannes G.
Published: May 2020

This review describes the state-of-the-art of metal-catalyzed selective transfer hydrogenation of α,β-unsaturated aldehydes and ketones to the allylic alcohols, covering the literature of the last 30 years.
Microfluidic assessment of red blood cell mediated microvascular occlusion
Authors: Man Yuncheng , Kucukal Erdem , An Ran , Watson Quentin D. , Bosch Jürgen , Zimmerman Peter A. , Little Jane A. , Gurkan Umut A.
Published: May 2020

A gradient of microcapillary networks and microfluidic anastomoses enable standardized quantitative assessment of red blood cell mediated microvascular occlusion.
Diphenyl diselenide protects a Caenorhabditis elegans model for Huntington’s disease by activation of the antioxidant pathway and a decrease in protein aggregation
Authors: Bicca Obetine Baptista Fabiane , Arantes Leticia Priscilla , Machado Marina Lopes , da Silva Aline Franzen , Marafiga Cordeiro Larissa , da Silveira Tássia Limana , Soares Felix Alexandre Antunes
Published: May 2020

Huntington’s disease (HD) is an autosomal dominant, progressive neurodegenerative disease with a distinct phenotype. It occurs due to a mutation in the huntingtin (or IT19) gene with an abnormal CAG repeat, leading to a variable length N-terminal polyglutamine chain (poly-Q). Like most neurodegenerative diseases, HD is characterized by the abnormal deposition and aggregation of proteins in the cell, which impairs the proteostasis and disrupts cellular homeostasis. In this study, we used Caenorhabditis elegans as an animal model due to its easy genetic manipulation and high homology of genes and signaling pathways with mammals. Worms were exposed to diphenyl diselenide (PhSe)2 at 25, 50 and 100 μM, and then we analyzed the polyQ aggregation, neurodegeneration, touch response, reactive oxygen species (ROS) levels, lifespan and health span. In addition, we analyzed the involvement of the transcription factor DAF-16, a FOXO-ortholog, and the downstream heat-shock protein-16.2 (HSP-16.2) and superoxide dismutase-3 (SOD-3). Our data demonstrate that chronic treatment with (PhSe)2 reduced polyQ aggregation in muscle and polyQ mediated neuronal cell death of sensory neurons ASH, as well as maintaining the neuronal function. In addition, (PhSe)2 decreased ROS levels and extended the lifespan and health span of wild type and PolyQ mutant worms. The mechanism proposed is the activation of DAF-16, HSP-16.2 and SOD-3 in whole body tissues to increase the antioxidant capacity and regulation of proteostasis, decreasing PolyQ aggregation and toxicity and reducing ROS levels, leading to an increase in lifespan, and healthspan. Our findings provide new clues for treatment strategies for neurodegenerative diseases and other diseases caused by age-related protein aggregation.
IR820 functionalized melanin nanoplates for dual-modal imaging and photothermal tumor eradication
Authors: Qu Botao , Zhang Xiaomin , Han Yahong , Peng Xiaoyang , Sun Jinghua , Zhang Ruiping
Published: May 2020

MNP-PEG-IR820 nanoplates were designed as a nano-theranostic material for dual-modal NIR-I fluorescence/photoacoustic imaging and photothermal tumor eradication.
Preparation of MOF catalysts and simultaneously modulated metal nodes and ligands via a one-pot method for optimizing cycloaddition reactions
Authors: Wang Peng , Wang Sha , Zhang Wenlei , Li Xiaohan , Gu Zhida , Li Wenze , Zhao Shuang , Fu Yu
Published: May 2020

MOFs were adjusted with metal nodes and ligands to endow them with Lewis acids and Brønsted acids for enhanced cycloaddition reactions.
Non-photoisomerizable butterfly shaped tetrasubstituted azobenzenes: synthesis and photophysical studies
Authors: Raman Arunachalam , Neelambra Afeefah U. , Karunakaran Venugopal , Easwaramoorthi Shanmugam
Published: May 2020

The trans-azobenzene (AB) substituted derivatives with bulky carbazole (1), phenothiazine (2), and phenyl (3) have been synthesized to understand the effect of steric crowding around the –NN– linkage on the photoisomerization process.
Catalytic oxidation mechanisms of carbon monoxide over single- and double-vacancy Mn-embedded graphene
Authors: Luo Mingming , Liang Zhao , Chen Mingwei , Peera Shaik Gouse , Liu Chao , Yang Hui , Qi Xiaopeng , Liu Juan , Liang Tongxiang
Published: May 2020

CO oxidation on MnC3 and MnC4 has fast kinetics and a low energy barrier.
Transparent, flexible MAPbI3perovskite microwire arrays passivated with ultra-hydrophobic supramolecular self-assembly for stable and high-performance photodetectors
Authors: Rao K. D. M. , Hossain Mozakkar , Umesh  , Roy Aniket , Ghosh Anudeepa , Kumar Gundam Sandeep , Moitra Parikshit , Kamilya Tapas , Acharya Somobrata , Bhattacharya Santanu
Published: May 2020

Fully transparent perovskite microwire arrays passivated with supramolecular assembly for stable and high-performance photodetectors.
High-resolution structural mapping and single-domain switching kinetics in 2D-confined ferroelectric nanodots for low-power FeRAM
Authors: Chen Yingxin , Xu Minhui , Hu Xin , Yue Yifeng , Zhang Xuefeng , Shen Qundong
Published: May 2020

2D-confined P(VDF-TrFE) nanodots with well-orientation crystals have been fabricated by the nano-imprinting lithography, and the structural maps and domain switching kinetics of P(VDF-TrFE) nanodots were characterized by AFM-based technology.
Ab initio nanofluidics: disentangling the role of the energy landscape and of density correlations on liquid/solid friction
Authors: Tocci Gabriele , Bilichenko Maria , Joly Laurent , Iannuzzi Marcella
Published: May 2020

Ab initio molecular dynamics reveals that subtle variations in the energy landscape and density correlations can change by up to one order of magnitude the slippage of water on two-dimensional materials.
Constructing a library of metal and metal–oxide nanoparticle heterodimers through colloidal assembly
Authors: Gschneidtner Tina A. , Lerch Sarah , Olsén Erik , Wen Xin , Liu Amelia C. Y. , Stolaś Alicja , Etheridge Joanne , Olsson Eva , Moth-Poulsen Kasper
Published: May 2020

Nanoparticle dimers composed of different metals or metal oxides, as well as different shapes and sizes, are of wide interest for applications ranging from nanoplasmonic sensing to nanooptics to biomedical engineering.
Enantioselective synthesis of indanone spiro-isochromanone derivatives via a dinuclear zinc-catalyzed Michael/transesterification tandem reaction
Authors: Yang Xiao-Chao , Xu Meng , Wang Jin-Bao , Liu Meng-Meng , Mathey François , Hua Yuan-Zhao , Wang Min-Can
Published: May 2020

A series of enantiomerically pure indanone spiro-isochromanones are obtained via a dinuclear zinc catalyzed asymmetric tandem Michael addition/transesterification reaction of α-hydroxy indanones with ortho-ester chalcones.
Controlling the crystal structure of precisely spaced polyethylene-like polyphosphoesters
Authors: Haider Tobias , Suraeva Oksana , O'Duill Miriam L. , Mars Julian , Mezger Markus , Lieberwirth Ingo , Wurm Frederik R.
Published: May 2020

We report the synthesis and crystallization behavior of polyethylene-like polyphosphates with a precise spacing of 20, 30, and 40 methylene groups between each phosphate group, which determined the crystal structure, lamellar, and crystal thickness.
Morphological evolution and mechanical properties of an “anchor chain” nanodomain structure of a reactive amphiphilic triblock copolymer in epoxy resin
Authors: Zhou Quan , Liu Qi , Yu Yueru , Zhuang Yuxiao , Lv Yizhe , Xiao Hanliang , Song Ning , Ni Lizhong
Published: May 2020

A epoxy-reactive poly(3,4-epoxycyclohexylmethyl methacrylate)-block-poly(dimethylsiloxane)-block-poly(3,4-epoxycyclohexylmethyl methacrylate) (PMETHB-b-PDMS-b-PMETHB) triblock can self-assemble in epoxy resin to form “anchor-chain” nanodomains.
Effect of the side ethylene glycol and hydroxyl groups on the polymerization kinetics of oligo(ethylene glycol methacrylates). An experimental and modeling investigation
Authors: Siddiqui Mohammad Nahid , Achilias Dimitris S. , Redhwi Halim Hamid
Published: May 2020

Polymerization of oligo(ethylene glycol) methyl ether methacrylate (POEGMMA300) and oligo(ethylene glycol) hydroxyethyl methacrylate (POEGHEMA).
Two-dimensional β-MoO3@C nanosheets as high-performance negative materials for supercapacitors with excellent cycling stability
Authors: Liu Xuexia , Wu Ying , Wang Huiwen , Wang Yinfeng , Huang Chunfang , Liu Limin , Wang Zhijun
Published: May 2020

MoO3 has gained a great deal of attention as a promising electrode material in energy storage devices.
Fabrication of a magnetic ternary ZnFe2O4/TiO2/RGO Z-scheme system with efficient photocatalytic activity and easy recyclability
Authors: Sun Yuwei , Lei Jiashuang , Wang Yizhu , Tang Qian , Kang Chunli
Published: May 2020

A magnetic separable Z-scheme composite based on ZnFe2O4, TiO2 nanosheets and RGO exhibits efficient photocatalytic degradation of p-NP.
One pot fabrication of fluorescein functionalized manganese dioxide for fluorescence “Turn OFF–ON” sensing of hydrogen peroxide in water and cosmetic samples
Authors: Ali Hassan Refat H. , Hassan Ahmed I. , Hassan Yasser F. , El-Wekil Mohamed M.
Published: May 2020

The fluorometric nanoprobe was fabricated via doping of fluorescein dye in MnO2 nanosheets (FLS/MnO2 NS) via facile co-precipitation method. It was used for analysis of H2O2 in different matrices through liberation of FLS after reduction of MnO2 NS.
Chlorotrifluoroethylidenes: an efficient and convenient approach to their synthesis
Authors: Upare Abhay Atmaram , Gadekar Pradip K. , Jadhav Kiran , Sivaramakrishnan H. , Roopan Selvaraj Mohana
Published: May 2020

A convenient one step synthesis of chlorotrifluoroalkyl olefins starting from aldehydes was developed.
Nano-TiO2 promoted CaO-based high-temperature CO2 sorbent: influence of crystal level properties on the CO2 sorption efficiency
Authors: Maiti Sanat Chandra , Ghoroi Chinmay
Published: May 2020

This work investigates the multi-cycle CO2 sorption and the kinetics of the carbonation reaction of nano-TiO2 promoted CaO synthesized from commercially available micron sized CaCO3.
Structural trends in the dehydrogenation selectivity of palladium alloys
Authors: Purdy Stephen C. , Seemakurthi Ranga Rohit , Mitchell Garrett M. , Davidson Mark , Lauderback Brooke A. , Deshpande Siddharth , Wu Zhenwei , Wegener Evan C. , Greeley Jeffrey , Miller Jeffrey T.
Published: May 2020

Alloying is well-known to improve the dehydrogenation selectivity of pure metals, but there remains considerable debate about the structural and electronic features of alloy surfaces that give rise to this behavior.
Evolution of pure hydrocarbon hosts: simpler structure, higher performance and universal application in RGB phosphorescent organic light-emitting diodes
Authors: Wang Qiang , Lucas Fabien , Quinton Cassandre , Qu Yang-Kun , Rault-Berthelot Joëlle , Jeannin Olivier , Yang Sheng-Yi , Kong Fan-Cheng , Kumar Sarvendra , Liao Liang-Sheng , Poriel Cyril , Jiang Zuo-Quan
Published: May 2020

In this work, we propose pure hydrocarbon materials as universal hosts for high-efficiency red, green and blue phosphorescent organic light-emitting diodes.
Asymmetric synthesis of primary amines catalyzed by thermotolerant fungal reductive aminases
Authors: Mangas-Sanchez Juan , Sharma Mahima , Cosgrove Sebastian C. , Ramsden Jeremy I. , Marshall James R. , Thorpe Thomas W. , Palmer Ryan B. , Grogan Gideon , Turner Nicholas J.
Published: May 2020

Fungal reductive aminases as effective biocatalysts for the preparation of chiral primary amines.
Evaluation of the subtle trade-off between physical stability and thermo-responsiveness in crosslinked methylcellulose hydrogels
Authors: Bonetti Lorenzo , De Nardo Luigi , Variola Fabio , Fare' Silvia
Published: May 2020

Fine-tuning of the chemical crosslinking in MC-based hydrogels increases their physical stability and mechanical properties while preserving their thermo-responsive behavior.
A novel degradation mechanism of the elastic modulus of wet polymer substrates under nanoindentation
Authors: Chen Ruling , Wang Zhe , Li Shaoxian , Du Hongwei
Published: May 2020

The decrease of elastic modulus of wet polymer is due to the appearance and solidification of confirmed water film.
High-humidity processed perovskite solar cells
Authors: Mohamad Noh Mohamad Firdaus , Arzaee Nurul Affiqah , Nawas Mumthas Inzamam Nawas , Mohamed Nurul Aida , Mohd Nasir Siti Nur Farhana , Safaei Javad , Yusoff Abd Rashid bin Mohd , Nazeeruddin Mohammad Khaja , Mat Teridi Mohd Asri
Published: May 2020

Perovskite solar cells (PSCs) are considered the next-in-line technology in the solar industry.
A three-dimensional interconnected V6O13 nest with a V5+-rich state for ultrahigh Zn ion storage
Authors: He Pingge , Liu Jiahao , Zhao Xudong , Ding Zhengping , Gao Peng , Fan Li-Zhen
Published: May 2020

Ultrahigh Zn ion storage is achieved by tuning the valence state and constructing a three-dimensional structure on V6O13 multi-valent oxide cathodes.
Antimicrobial peptide CGA-N12 decreases the Candida tropicalis mitochondrial membrane potential via mitochondrial permeability transition pore
Authors: Li Ruifang , Zhao Jiarui , Huang Liang , Yi Yanjie , Li Aihua , Li Dandan , Tao Mengke , Liu Youhao
Published: May 2020

Amino acid sequence from 65th to 76th residue of the N-terminus of Chromogranin A (CGA-N12) is an antimicrobial peptide (AMP). Our previous studies showed that CGA-N12 reduces Candida tropicalis mitochondrial membrane potential. Here, we explored the mechanism that CGA-N12 collapsed the mitochondrial membrane potential by investigations of its action on the mitochondrial permeability transition pore (mPTP) complex of C. tropicalis. The results showed that CGA-N12 induced cytochrome c (Cyt c) leakage, mitochondria swelling and led to polyethylene glycol (PEG) of molecular weight 1000 Da penetrate mitochondria. mPTP opening inhibitors bongkrekic acid (BA) could contract the mitochondrial swelling induced by CGA-N12, but cyclosporin A (CsA) could not. Therefore, we speculated that CGA-N12 could induce C. tropicolis mPTP opening by preventing the matrix-facing (m) conformation of adenine nucleotide transporter (ANT), thereby increasing the permeability of the mitochondrial membrane and resulted in the mitochondrial potential dissipation.
Materno-fetal cholesterol transport during pregnancy
Authors: Kallol Sampada , Albrecht Christiane
Published: May 2020

Cholesterol is a major nutrient required for fetal growth. It is also a precursor for the synthesis of steroid hormones and essential for the development and maturation of fetal organs. During pregnancy, the placenta controls the transport of cholesterol from the mother to the fetus and vice versa. Cholesterol originating from the maternal circulation has to cross two main membrane barriers to reach the fetal circulation: Firstly, cholesterol is acquired by the apical side of the syncytiotrophoblast (STB) from the maternal circulation as high-density lipoprotein (HDL)-, low-density lipoprotein (LDL)- or very-low-density lipoprotein (VLDL)-cholesterol and secreted at the basal side facing the villous stroma. Secondly, from the villous stroma cholesterol is taken up by the endothelium of the fetal vasculature and transported to the fetal vessels. The proteins involved in the uptake of HDL-, LDL-, VLDL- or unesterified-cholesterol are scavenger receptor type B class 1 (SR-B1), cubulin, megalin, LDL receptor (LDLR) or Niemann–Pick-C1 (NPC1) which are localized at the apical and/or basal side of the STB or at the fetal endothelium. Through interaction with apolipoproteins (e.g. apoA1) cholesterol is effluxed either to the maternal or fetal circulation via the ATP-binding-cassette (ABC)-transporter A1 and ABCG1 localized at the apical/basal side of the STB or the endothelium. In this mini-review, we summarize the transport mechanisms of cholesterol across the human placenta, the expression and localization of proteins involved in the uptake and efflux of cholesterol, and the expression pattern of cholesterol transport proteins in pregnancy pathologies such as pre-eclampsia, gestational diabetes mellitus and intrauterine growth retardation.
Bidirectional interaction of airway epithelial remodeling and inflammation in asthma
Authors: Banno Asoka , Reddy Aravind T. , Lakshmi Sowmya P. , Reddy Raju C.
Published: May 2020

Asthma is a chronic disease of the airways that has long been viewed predominately as an inflammatory condition. Accordingly, current therapeutic interventions focus primarily on resolving inflammation. However, the mainstay of asthma therapy neither fully improves lung function nor prevents disease exacerbations, suggesting involvement of other factors. An emerging concept now holds that airway remodeling, another major pathological feature of asthma, is as important as inflammation in asthma pathogenesis. Structural changes associated with asthma include disrupted epithelial integrity, subepithelial fibrosis, goblet cell hyperplasia/metaplasia, smooth muscle hypertrophy/hyperplasia, and enhanced vascularity. These alterations are hypothesized to contribute to airway hyperresponsiveness, airway obstruction, airflow limitation, and progressive decline of lung function in asthmatic individuals. Consequently, targeting inflammation alone does not suffice to provide optimal clinical benefits. Here we review asthmatic airway remodeling, focusing on airway epithelium, which is critical to maintaining a healthy respiratory system, and is the primary defense against inhaled irritants. In asthma, airway epithelium is both a mediator and target of inflammation, manifesting remodeling and resulting obstruction among its downstream effects. We also highlight the potential benefits of therapeutically targeting airway structural alterations. Since pathological tissue remodeling is likewise observed in other injury- and inflammation-prone tissues and organs, our discussion may have implications beyond asthma and lung disease.
Robust set‐membership state estimator against outliers in data
Authors: Meslem Nacim , Hably Ahmad
Published: May 2020

Based on interval computation, a set‐membership state estimator capable to manage a certain type of outliers in measurements is proposed for uncertain discrete‐time linear systems. To achieve this purpose, two set‐valued filtering techniques are implemented in the presented state estimation algorithm. The setting up of these techniques offers two main advantages. On one hand, the convergence of the estimated state enclosures width is guaranteed and, on the other hand, the algorithm robustness against outliers in data is ensured. That is, unlike former methods, the proposed set‐valued state estimator preserves the framing property despite the presence of some false values in available sensors data. To show the efficiency and the performance of the introduced set‐valued state estimator, it is compared, through two numerical examples, with an optimal interval observer selected from the literature for its high performance.
Command filtered finite‐time formation tracking control of AUVs with unknown control directions
Authors: Gao Zhenyu , Guo Ge
Published: May 2020

This study investigates a formation control problem of autonomous underwater vehicles (AUVs) with unknown control directions. By employing the Nussbaum gain technique to deal with the unknown control directions, a finite‐time formation control approach is proposed. To deal with the so‐called ‘explosion of complexity’ issue in backstepping control, a compensator‐based command filter technique is introduced to realise the derivative of virtual control signals. With the proposed method, the formation can be achieved within a finite settling time and all signals in the closed‐loop system are uniformly bounded. The effectiveness and performance is demonstrated by numerical simulations.
Traffic management system for smart road networks reserved for self‐driving cars
Authors: Di Febbraro Angela , Gallo Federico , Giglio Davide , Sacco Nicola
Published: May 2020

A model of a smart road network consisting of unsignalised intersections and smart roads connecting them is considered in this work with the aim of presenting a traffic management system for self‐driving cars (or, more generally, autonomous vehicles) which travel the network. The proposed system repeatedly solves a set of mathematical programming problems (each of them relative to a single intersection or to a single road stretch of the network) within a decentralised control scheme in which each local intersection controller and each local road controller communicates with the fully autonomous vehicles in order to receive travel data from vehicles and to provide speed profiles to them once determined the optimal solution of the problem. In order to reduce the computational effort required to provide the optimal solution, a discrete‐time approach is adopted so that, in each time interval, a limited number of vehicles are taken into consideration; in this way, solutions can be determined in a very short time thus making the proposed model compatible with a practical application to real traffic systems. The proposed model is general enough, and can be adapted to different scenarios of smart road networks reserved for self‐driving cars.
Speed harmonisation and merge control using connected automated vehicles on a highway lane closure: a reinforcement learning approach
Authors: Ko Byungjin , Ryu Seunghan , Park Byungkyu Brian , Son Sang Hyuk
Published: May 2020

A lane closure bottleneck usually leads to traffic congestion and a waste of fuel consumption on highways. In mixed traffic that consists of human‐driven vehicles and connected automated vehicles (CAVs), the CAVs can be used for traffic control to improve the traffic flow. The authors propose speed harmonisation and merge control, taking advantage of CAVs to alleviate traffic congestion at a highway bottleneck area. To this end, they apply a reinforcement learning algorithm called deep Q network to train behaviours of CAVs. By training the merge control Q‐network, CAVs learn a merge mechanism to improve the mixed traffic flow at the bottleneck area. Similarly, speed harmonisation Q‐network learns speed harmonisation to reduce fuel consumption and alleviate traffic congestion by controlling the speed of following vehicles. After training two Q‐networks of the merge mechanism and speed harmonisation, they evaluate the trained Q‐networks under various conditions in terms of vehicle arrival rates and CAV market penetration rates. The simulation results indicate that the proposed approach improves the mixed traffic flow by increasing the throughput up to 30% and reducing the fuel consumption up to 20%, when compared to the late merge control without speed harmonisation.
Probabilistic available transfer capability assessment in power systems with wind power integration
Authors: Sun Xin , Tian Zhongbei , Rao Yufei , Li Zhaohui , Tricoli Pietro
Published: May 2020

Extending current deterministic tools to incorporate significant stochastic wind power is becoming an important as well as challenging task for present‐day power system decision‐making. This study proposes a novel probabilistic assessment method to assess the available transfer capability (ATC). Usually, repeated ATC evaluations with an exhaustive set of samples are needed to obtain converged results by the Monte Carlo simulation. To alleviate the computation burden, a statistically‐equivalent surrogate model for the ATC solution is constructed based on the canonical low‐rank approximation (LRA). By implementing LRA for the base case and a set of enumerated contingencies, the uncertainties of wind power generation and load, as well as transmission equipment outages, are addressed efficiently. With the proposed method, the probabilistic ATC is characterised, and the most influential uncertain factors are identified, which helps to determine a suitable ATC level. The effectiveness of the proposed method is validated via case studies with a modified IEEE 118‐bus system.
Distributed Newton‐based voltage control method for high‐penetration PV generation cluster in active distribution networks
Authors: Wang Zhongguan , Ge Leijiao , Ding Jinjin , Gu Weide
Published: May 2020

Renewable energy generation exhibits a distributed development trend, and has changed the way distribution networks operated. Due to the integration of large‐scale distributed photovoltaic (PV) generation cluster and the access of electronic devices, distribution networks are suffering from more and more serious voltage risks. By using appropriate methods, PV inverters can autonomously regulate reactive power output in a distributed manner to improve voltage profile in networks. In this paper, a distributed Newton‐based voltage control method for large‐scale PV generation cluster in distribution networks is presented to realize distributed coordination of PV inverters, which is based on matrix splitting and approximate Newton iteration, and can fast respond to reactive power mismatch and realize voltage profiles optimization. Exhibiting a more efficient, reliable and flexible performance than existing decentralized methods in IEEE test systems with different PV penetration, the proposed method is demonstrated to be effectively to organize and control PV cluster to realize fast voltage optimization in distribution networks.
Green synthesis and antimicrobial evaluation of silver nanoparticles mediated by leaf extract of Syzygium cumini against poultry pathogens
Authors: Rizwan Muhammad , Hussain Muhammad , Muhammad  , Rauf Abdur , Zafar Muhammad Naveed , Mabkhot Yahia N. , Maalik Aneela
Published: May 2020

The present study was carried out to determine the effect of plant extract of Syzygium cumini and their silver nanoparticles (AgNPs) against the poultry pathogens. The plant extract was prepared in methanol, ethanol, ethyl acetate, chloroform, and n‐hexane. The results of phytochemical screening showed that the leaf extract of S. cumini have medicinally important phytochemical constituents. In the present study, AgNPs were synthesised by using an extract of S. cumini. Synthesised AgNPs were confirmed by Fourier‐transform infrared spectroscopy, ultraviolet–visible, and scanning electron microscopy. A surface plasmon resonance peak in absorption spectra showed absorption at 419 nm. The synthesised nanoparticles were found spherical in shape with the diameter range of 30–120 nm. The antimicrobial activity of crude extract and AgNPs was checked against the poultry bacterial pathogens by the agar well diffusion method. The authors’ findings revealed that the crude extract and AgNPs have promising activities against all the test pathogens. It is concluded that the bioactive compounds from the extract of S. cumini and extract‐mediated AgNPs can be significantly used as an alternate poultry medicine to replace the available antibiotics, which have adverse side effects.
Determination of Hamaker constant for CNT and AFM probe configuration inside SEM
Authors: Yang Quan
Published: May 2020

Mounting the atomic force microscope (AFM) probe on the gripper of the robotic nanoscale manipulators system enables the combination of the AFM and scanning electron microscope (SEM). The AFM–SEM‐based method of determining Hamaker constant for carbon nanotube (CNT) and AFM cantilever in the vacuum condition of SEM, which is completed through a robotic nanoscale manipulators system, is presented for the first time. During Hamaker constant determining experiment, the elastic force is measured utilising integrated AFM–SEM imaging technique through detecting the deflection of AFM cantilever that actually equals van der Waals adhesion force. The van der Waals attraction force between CNT and AFM cantilever is calculated through the modelling of a cylindrical nanotube and a flat gold‐coated surface. The experiment results indicate that Hamaker's constant measured are comparable to typical values published by previous researchers, being of the order of 100 zJ, which indicates that the present approach is valid and reliable.
The GOGREEN Survey: A deep stellar mass function of cluster galaxies at 1.0 < z < 1.4 and the complex nature of satellite quenching
Authors: van der Burg Remco F. J. , Rudnick Gregory , Balogh Michael L. , Muzzin Adam , Lidman Chris , Old Lyndsay J. , Shipley Heath , Gilbank David , McGee Sean , Biviano Andrea , Cerulo Pierluigi , Chan Jeffrey C. C. , Cooper Michael , De Lucia Gabriella , Demarco Ricardo , Forrest Ben , Gwyn Stephen , Jablonka Pascale , Kukstas Egidijus , Marchesini Danilo , Nantais Julie , Noble Allison , Pintos-Castro Irene , Poggianti Bianca , Reeves Andrew M. M. , Stefanon Mauro , Vulcani Benedetta , Webb Kristi , Wilson Gillian , Yee Howard , Zaritsky Dennis
Published: May 2020

We study the stellar mass functions (SMFs) of star-forming and quiescent galaxies in 11 galaxy clusters at 1.0 < z < 1.4 drawn from the Gemini Observations of Galaxies in Rich Early ENvironments (GOGREEN) survey. Based on more than 500 h of Gemini/GMOS spectroscopy and deep multi-band photometry taken with a range of observatories, we probe the SMFs down to a stellar mass limit of 109.7 M⊙ (109.5 M⊙ for star-forming galaxies). At this early epoch, the fraction of quiescent galaxies is already highly elevated in the clusters compared to the field at the same redshift. The quenched fraction excess (QFE) represents the fraction of galaxies that would be star-forming in the field but are quenched due to their environment. The QFE is strongly mass dependent, and increases from ∼30% at M⋆ = 109.7 M⊙ to ∼80% at M⋆ = 1011.0 M⊙. Nonetheless, the shapes of the SMFs of the two individual galaxy types, star-forming and quiescent galaxies, are identical between cluster and field to high statistical precision. Nevertheless, along with the different quiescent fractions, the total galaxy SMF is also environmentally dependent, with a relative deficit of low-mass galaxies in the clusters. These results are in stark contrast with findings in the local Universe, and therefore require a substantially different quenching mode to operate at early times. We discuss these results in light of several popular quenching models.
Improving the environmental assessment of objects in the system of construction engineering
Authors: Bespalov Vadim , Kotlyarova Ekaterina
Published: May 2020

The problem of maintaining the proper level of environmental safety in urban areas currently is not yet fully resolved. In this case, a special role at the level of impact on the environment is played by the industry of design, construction and operation of construction projects and urban facilities for various purposes. To solve this issue in our research, we identified and systematized the main characteristics of the groups, which largely determine the state of both individual objects of the urban environment and urban economy, and urbanized territories as a whole. As a result, groups of environmental, economic and social characteristics were obtained. In addition, we paid attention to the distribution of the importance of the evaluation criteria regarding the type of functional zone of the urbanized territory. Further in the article, we proposed to determine the environmental criteria based on the characteristics of the state of individual components of the surrounding urban environment and the characteristics of economic activity in the territory under consideration, causing qualitative changes in the state of this environment. Our research allows us to identify the dominant importance of the environmental criteria for a specific urbanized area and the need to take it into account at the initial design stage. At further stages, we intend to conduct scientific research to derive a dimensionless indicator based on the environmental criteria described above with the further development of an appropriate methodology, which will allow us to assess comprehensively the degree of construction projects and urban facilities for various purposes impact on the environmental safety of urbanized territories and develop appropriate measures for its optimization and reduction.
Soundproofing presses by placing its nodes in a soundproof casing, including drive components
Authors: Pushenko Sergei , Bozhko Evgeny , Zolotuhina Irina
Published: May 2020

Noise is one of the most unfavorable environmental factors in production facilities, for which it is most difficult to achieve compliance with sanitary standards. Prolonged exposure to intense vibrations and noise leads to noise and vibration diseases. The effect of noise on the human body is not limited to exposure to the organ of hearing. Irritation by noise is transmitted to the central and autonomic nervous systems, through them acts on the internal organs, leading to significant changes in the functional state of the organism. With pulsed and irregular noise, the degree of impact of noise on the body of workers increases. Most types of forging equipment relate to impact machines, during the operation of which impulse noise occurs, the levels of which at workplaces, in most cases, exceed the maximum permissible values and relate to those factors, the significance of which in some cases is greater than dustiness, high temperature, manipulation of heated workpieces. Therefore, the problem of reducing vibration and noise in the forge shops is extremely relevant and has great scientific and socio-economic significance. To solve the problem of noise reduction in forge shops, various options for reducing the noise activity of equipment have been developed/ It is possible to most effectively reduce noise by changing the material and shapes of the beds, noise-attenuating casings, oil baths for gears.
A review on buildings energy consumption in Russia: educational buildings
Authors: Lanko Aleksandr , Sanchez de la Flor Francisco Jose , Narezhnaya Tamara
Published: May 2020

To understand the importance of implementing energy-saving technologies in educational buildings, it is necessary to assess current energy consumption. The main goal of the article is to show the level of energy consumption of educational buildings in Russia. The main method of the study is to collect information from various sources and to analyze it in order to identify the factors that have the greatest impact on the volume of energy consumption. The collected information for Federal districts is compared with each other, and the average data for Russia is compared with figures for similar buildings in the European Union and North America. A comparison of the resulting data for the Federal districts of Russia shows that climate is one of the most important factors affecting energy consumption. As a result, according to different estimates, the total energy consumption in educational buildings is from 240 to 400 kWh/m2. It is one of the highest in comparison with developed countries of the European Union and North America.
Linear best method for recovering the second derivatives of Hardy class functions
Authors: Ovchintsev Mikhail
Published: May 2020

The linear best method for approximating the second derivatives of Hardy class functions defined in the unit circle at zero in accordance with the information about their values in a finite number of points forming a regular polygon is found. The paper is divided into three sections. The first contains the necessary concepts and results from the work of K.Yu. Osipenko. It also recalls some results obtained by S. Ya. Havinson and other authors. In the second section, the error of the best method is calculated, and the corresponding extremal functions are written out. The third proves that the linear best approximation method is unique, and its coefficients are calculated.
Prospects for the creation of smart homes using energy-saving wall ceramic materials
Authors: Turchenko Alla , Davydova Tatiana , Spivak Irina
Published: May 2020

The article discusses the prospects of energy saving in a ‘smart home’, taking into account the characteristics of consumer behavior. It is shown that the technical characteristics of the building in conditions of insufficient consumer awareness (passive approach to energy conservation) are preferable to the characteristics associated with intelligent solutions (active approach). It was revealed that special attention is paid to assessing the possibility of reducing the energy loss of a building by wall enclosures. In this regard, the effectiveness of the use of popular wall structural and heat-insulating materials, which reduce energy and material consumption in their production, is analyzed. The rationality of the production of porous ceramic products by the method of introducing into the mixture of mineral pore-forming additives with plastic molding is proved. A composition of porous ceramic material has been developed using local raw materials to create wall structural and heat-insulating products that meet the requirements of energy conservation.
Controlled optimization model for traffic zones during road repair periods
Authors: Kondrashova Elizaveta
Published: May 2020

The aim of the research is construct a model that allows to make the best decisions while carrying out repairs on the road. These decisions can be made taking into account both the interests of the participants of the traffic and taking into account the costs spent on repair. This paper presents optimization model for traffic zones using queueing controlled models in searching for an optimal management strategy. This optimal strategy is based on the theory of controlled semi-Markov processes. As a result we have controlled model for use during road repair periods. The model can be complicated and varied depending on the conditions.
Adhesion of car tires to the road surface during reconstruction of road accidents
Authors: Evtukov Stanislav , Golov Egor
Published: May 2020

Road and weather conditions have a significant impact on the occurrence of road accidents and their development as events. According to these circumstances, the system “Driver – Car – Road – Environment” identifies certain types of expertise that are engaged in determining the presence and magnitude of the parameters of the road environment that affect the development of the road transport situation. When conducting relevant investigations, the experts calculate the speed and length of the stopping distance of the vehicle, using coefficients that determine the impact of road conditions on the road traffic situation under study. One of these important indicators is the coefficient of adhesion of car tires to the road surface. Due to the lack of technical capability to experimentally determine the coefficient of adhesion at the place of an accident, many experts are forced to use values from the reference literature. This study is devoted to checking the agreement of reference values of this indicator with actual values that correspond to the conditions of driving on Russian roads. To solve this problem, full-scale measurements were made of the coefficient of adhesion of tires with a coating on more than 2000 km of roads in different regions of Russia (with different climatic and topographic conditions) and the results of field research were analyzed.
The study of rolling stock wheels impact on rail switch frogs
Authors: Korolev Vadim
Published: May 2020

Studies of stress distribution across cross sections by polarization-optical method made it possible to propose a relatively simple experimental method of determining contact forces. Experimental determination of contact forces on crossbars of switches is possible by means of sensors located in places of stress concentration (at core base). Analysis of oscillations during impact-pulse loading makes it possible to determine design parameters of the path. Typically, single circuits with four to five degrees of freedom produce quite satisfactory results and may be recommended for the calculated determination of contact forces on the crossbars of the switches.
Designing the height of the first profile of the marshalling hump
Authors: Turanov Khabibulla , Gordienko Andrej , Saidivaliev Shukhrat , Djabborov Shukhrat
Published: May 2020

The height of the high-speed section of the sorting slide. Design of high-speed section of the marshalling hump. To prove mathematically the absence of theoretical basis of the formula by which the height of the first profile section of the marshalling hump is calculated in current method of calculation of marshalling humps. The paper uses the theorem on the change of kinetic energy for a non-free material point in the final form, known from theoretical mechanics. The results of the research revealed that the formulas by which the height of the first profile section of the marshalling hump is calculated contradict the theorem on the change of kinetic energy for a non-free material point in the final form. The results of the research can be used in the processing of the normative-technical document on the design of hump devices on railways and making adjustments to the dynamics of rolling the car in textbooks for universities of railway transport. The results of the calculations proved the incorrectness of the derivation of the formula for calculating the height of the first profile section of the marshalling hump in the normative-technical document “Rules and standards for the design of sorting devices on the railways with gauge 1 520 mm”.
The use of simulation when designing road junctions
Authors: Terentyev Vyacheslav , Andreev Konstantin , Anikin Nikolay , Morozova Natalya , Shemyakin Alexander
Published: May 2020

The high level of motorization in most countries of the world is the reason for the increase in the number of car accidents. Currently, it is understood that a further increase in the number of cars without significant changes in the transport infrastructure will only aggravate the already difficult situation on roads. The article addresses the issues of road traffic injuries and statistical information on road accidents. The analysis of the work of leading transport engineers presents the results of studies on the use of computer modeling tools for designing road conditions at various levels. From the presented analysis, it is possible to conclude that the most suitable tool for assessing the safety of road junctions is the PTV VISSIM software package, which also allows to export vehicle trajectories to SSAM software. In the framework of the analytic survey of the intersection safety, based on the analysis of vehicle trajectories, the parameters of the future conflict of the planned road junctions were established. Studies have shown that a road junction at different levels makes possible to triple the safety of junctions in comparison with the roundabout. The use of simulation allows not to wait for emergency cases, but to evaluate hypothetical structures and alternative layout options for road junctions, where it is not possible to use traditional, statistical models for assessing the probability of car accidents.
Technology for producing wear-resistant bimetal bearing based on cast aluminum
Authors: Kuznetsov Ruslan , Ol’khovik Evgeniy , Radkevich Mikhail , Kuznetsov Pavel
Published: May 2020

The paper presents the results of research the new technological process for producing bimetallic materials in the composition of “aluminum cast alloy - sintered iron powder” by the method of joint stamping of liquid metal. The purpose of this research is obtain parts with high wear-resistant properties, special sintered powder materials are used, which have an internal porosity to retain lubricant. However, such materials do not fit well with traditional aluminum alloys. This problem is may be solved by creating new bimetallic alloys, part of which is an outer casing, and the other materials is the functional bearing. To accomplish this task, we conducted a study of a new technology for joint stamping of liquid metal. In order to optimize and increase the reliability of the experiment, the pressing pressure, the pressure holding time, and the tooling temperature of the matrix were taken as quantitative factors. The effect of the applied pressure on the mechanical properties of the base material and the facing layer was determined on a longitudinal section of the obtained samples by the Vickers method. It was revealed that the gradient of increasing hardness is directed to the outer radius of the workpiece, that is, to the opposite crystallization front. The high level of bimetal adhesion is explained by the presence of a uniform moderate zone of mutual solubility, including due to the violation of the porous surface layer of the powder billet.
Accessibility of the urban environment for people with limited mobility using the example of Arkhangelsk
Authors: Popova Olga , Ostanina Alena , Belyaeva Svetlana , Andryunina Yana
Published: May 2020

The aim of the study is to assess the availability of urban space for people with limited mobility (PLM). Research objectives: - assessment of urban areas - determining the level of accessibility of the urban environment by assigning accessibility indices to certain territories (quarters); - testing using the example of separate quarters of the city of Arkhangelsk. Two non-adjacent city blocks located in its central part were selected for testing. According to the results of the study, it is possible to conclude that the availability of the urban environment for PLM in the selected quarters is: 37.2% for the first quarter, 42.1% for the second quarter. There is no comprehensive infrastructure suitable for PLM in the territory. Among the main problems are poor coating of footpaths, barriers in the form of curbs, the absence of railings on stairs, canopies and ramps, as well as the lack of equipped recreation places. A feature and advantage of the method is that the purpose of the study is not just a description of the quality characteristics of accessibility, but the determination of specific indicators of the security of various complex components of a comfortable urban environment. Integrated monitoring of the quality of the urban environment for PLM will allow the implementation of targeted programs and activities, taking into account their relevance to the expected effects. This contributes to the prudent use of financial resources. The totality of development programs and measures for individual territories will determine the development strategy of the city as a whole.
Function-topological model of urban space sectoral zoning
Authors: Denisov Denis , Zhuravleva Tatyana , Zhuravlev Mikhail , Kabanova Elena
Published: May 2020

This study supplements the function-topological model of analysis of city organization and development with a sectoral model of administrative-territorial division. The function-topological model allows revealing unique features of objects of the same profile, located in different space sectors. Besides, significant objects are usually placed in strictly defined sectors. Identification of general principles of spatial arrangement at all levels from geopolitics to the structure of private farmsteads on the cases of various cities, metropolitan areas and architectural ensembles is of great general scientific significance. It deals with the principles described in regional traditions: the Indian Vastu Vidya and the Chinese Feng Shui. The analysis shows that, on an intuitive level, the same principles are implemented in the activities of specialists, designers, who make decisions about the location of industries, residential areas and architectural complexes. Recognition and study of these principles are hindered by the materialistic attitudes of twentieth-century science. The results of the study lead to a radical step in recognizing many spatial elements of the mythological picture of the world as reliable ones.