bluuebunny/crossref_metadata_2025 huggingface dataset:
An Experimental Analysis of Model Compression Techniques for Object Detection
Authors: Salvi Andrey De Aguiar , Barros Rodrigo Coelho
Published: November 2020

Recent research on Convolutional Neural Networks focuses on how to create models with a reduced number of parameters and a smaller storage size while keeping the model’s ability to perform its task, allowing the use of the best CNN for automating tasks in limited devices, with reduced processing power, memory, or energy consumption constraints. There are many different approaches in the literature: removing parameters, reduction of the floating-point precision, creating smaller models that mimic larger models, neural architecture search (NAS), etc. With all those possibilities, it is challenging to say which approach provides a better trade-off between model reduction and performance, due to the difference between the approaches, their respective models, the benchmark datasets, or variations in training details. Therefore, this article contributes to the literature by comparing three state-of-the-art model compression approaches to reduce a well-known convolutional approach for object detection, namely YOLOv3. Our experimental analysis shows that it is possible to create a reduced version of YOLOv3 with 90% fewer parameters and still outperform the original model by pruning parameters. We also create models that require only 0.43% of the original model’s inference effort.
Quarenteners vs. Cloroquiners: a framework to analyze the effect of political polarization on social distance stances
Authors: Ebeling Régis , Sáenz Carlos Córdova , Nobre Jeferson Campos , Becker Karin
Published: November 2020

The worldwide COVID-19 pandemic has struck people’s lives overnight. With an alarming contagious rate and no effective treatments or vaccines, it has evoked all sorts of reactions. In this paper, we propose a framework to analyze how political polarization affects groups’ behavior with opposed stances, using the Brazilian COVID polarized scenario as a case study. Two Twitter groups represent the pro/against social isolation stances referred to as Chloroquiners and Quarenteners. The framework encompasses: a) techniques to automatically infer from users political orientation, b) topic modeling to discover the homogeneity of concerns expressed by each group; c) network analysis and community detection to characterize their behavior as a social network group and d) analysis of linguistic characteristics to identify psychological aspects. Our main findings confirm that Cloroquiners are right-wing partisans, whereas Quarenteners are more related to the left-wing. The political polarization of Chloroquiners and Quarenteners influence the arguments of economy and life, and support/opposition to the president. As a group, the network of Chloroquiners is more closed and connected, and Quarenteners have a more diverse political engagement. In terms of psychological aspects, polarized groups come together on cognitive issues and negative emotions.
Short-Term Forecasting in Bitcoin Time Series Using LSTM and GRU RNNs
Authors: De Caux Marcelo , Bernardini Flavia , Viterbo Jose
Published: November 2020

In recent years, bitcoin has become a very attractive investment in financial industry, which is not controlled by governments, but is based on trust between transfers under the technology of block chain. Hence, forecasting future bitcoin cryptocurrency values is a problem that has attracted the attention of many researchers in the field, while proving to be a very challenging problem. This work presents an experimental analysis using LSTM and GRUs for forecasting bitcoin values in a minute-granulated time for the entire next day. To this end we also present our methodology for conducting the experiments. The final goal is to create the core of a financial prediction tool around the RNNs. In our experiments, we achieved interesting results such as a SMAPE of 0.0002, a RMSE of US$ 3.844 and a rRMSE of 0.0028 in a day where bitcoin rates vary from US$ 13.2K and US$ 14.6K, surpassing the results of SMAPE found in the literature and proposed limit of SMAPE smaller than 0.007 for forecasts.
From audio to information: Learning topics from audio transcripts
Authors: Rodrigues João Pedro , Paraiso Emerson
Published: November 2020

In this work, the technical feasibility of working with audio transcriptions from Youtube is analyzed, as well as presenting a method that allows data acquisition, pre-processing, and post-processing to work with this type of data. A topic modeling approach with the latent dirichlet allocation algorithm is used. An approach is also presented to dynamically determine the ideal number of topics that make up a given corpus. In the experiments, a database of 250 audio transcriptions was used, obtaining a model with coherence in the range of 40%.
Experimenting Sentence Split-and-Rephrase Using Part-of-Speech Labels
Authors: Berlanga Neto P. , Okano E. Y. , Ruiz E. E. S.
Published: November 2020

Text simplification (TS) is a natural language transformation process that reduces linguistic complexity while preserving semantics and retaining its original meaning. This work aims to present a research proposal for automatic simplification of texts, precisely a split-and-rephrase approach based on an encoder-decoder neural network model. The proposed method was trained against the WikiSplit English corpus with the help of a part-of-speech tagger and obtained a BLEU score validation of 74.72%. We also experimented with this trained model to split-and-rephrase sentences written in Portuguese with relative success, showing the method’s potential.
A Characterization of Portuguese Tweets Regarding the Covid-19 Pandemic
Authors: Brum Pedro V. , Teixeira Matheus C. , Miranda Renato , Vimieiro Renato , Meira Jr Wagner , Pappa Gisele L.
Published: November 2020

Twitter has been one of the main sources of information and discussion during the COVID-19 pandemics. This paper characterizes a set of more than 56 million tweets written in Portuguese and collected over a period of 70 days. Our analysis includes the volume of messages, text of tweets, location of tweets, the main elements of tweets (e.g. hashtags and URLs) and the user profiles, including gender. The analyses showed the most discussed topics in the period were quarantine, hydroxychloroquine, agglomeration and social distance, and that the discussions were centered in political issues (e.g., most common hashtags include “fechadocombolsonaro" and “forabolsonaro").
Project Delivery System Decision Making using Pythagorean Fuzzy TOPSIS
Authors: Su Limin , Li Huimin , Cao Yongchao , Lv Lelin
Published: November 2020

The selection of project delivery systems is a complex decision-making process, which is also a critical task for owners. The complexity problem arises from the uncertainty of decision making environment and construction project itself. Pythagorean fuzzy sets (PFS), as an extension from intuitionistic fuzzy sets (IFSs) to deal with uncertainty information, has attracted more scholars’ attention in the decision making area. In this paper, we develop three similarity measures (i.e., 1-type PFSs similarity measure, 2-type PFSs weighted similarity measure, 3-type PFSs weighted similarity measure), and investigate their properties. Then an improved TOPSIS decision making framework is further established with PFSs information, in which the proposed similarity measures are employed to measure the similarity degree between each alternative and negative ideal solution and positive ideal solution. Finally, a case study of the selection of project delivery systems is presented to proof the performance of the proposed decision making method.
The Impact of Geriatric Emergency Management Nurses on the Care of Frail Older Patients in the Emergency Department: a Systematic Review
Authors: Leaker Hannah , Holroyd-Leduc Jayna Marie
Published: November 2020

Background

Frail older adults are high users of emergency departments (EDs). Many Canadian EDs have hired Geriatric Emergency Management (GEM) nurses in an effort to improve care to older adults.

Methods

We conducted a systematic review to determine the impact of GEM nurses on care provided to frail older adults. We searched MEDLINE, Embase, CINAHL, and Cochrane data­bases. A grey literature search was also conducted. Inclusion criteria were English-language, evaluation of GEM nurse or geriatric-trained nurse assessments of older adults (age ≥ 65 years) within the ED, and reported clinical and/or health sys­tem outcomes. The PRISMA statement was followed, and article quality was assessed using GRADE.

Results

5,115 citations and 191 full text articles were screened; 8 arti­cles from 7 different studies were included. Study quality var­ied between very low to high. Five included studies analyzed the effect of GEM nurses on ED revisits, with most finding they decreased revisits. Four included studies analyzed the effect of GEM nurses on hospital admissions/readmissions, demonstrating variable impact. One study looked at the cost-effectiveness and found the cost to be negligible. The impact on patient-specific outcomes was less clear.

Conclusions

GEM nurses may be an effective option to help in the manage­ment of frail older adults in the ED.
Ontario Geriatric Specialist Physician Resources 2018
Authors: Borrie Michael , Cooper Tracy , Basu Monisha , Kay Kelly , Prorok Jeanette , Seitz Dallas
Published: November 2020

Background

The number of older adults with complex health needs in Ontario is growing. The Ministry of Health and Long-Term Care requested a resource mapping project to assess the current 2018 and projected 2025 number of specialist physi­cian resources.

Methods

Geriatric specialist physicians were defined as geriatricians, geriatric psychiatrists, and Care of the Elderly (COE) physi­cians. We determined the current number of geriatricians, geri­atric psychiatrists, and COEs and clinical full-time-equivalent complement (CFTE) for geriatric medicine and geriatric psychiatry specialists. We projected the number of new train­ees expected to enter practice and the number of physicians expected to retire by 2025. We compared these numbers and projections against established specialist/population ratios for geriatricians and geriatric psychiatrists.

Results

There was a deficit of geriatricians and geriatric psychiatrists (geriatricians: CFTE deficit of 150.5; geriatric psychiatrists: CFTE deficit of 116.3). In 2025, the projected CFTE deficit of geriatricians will increase to at least 210.35 and geriatric psychiatrists to 194.6. Only about 30% of COE physicians work in direct support of specialized services for the elderly.

Conclusions

There is significant current and anticipated undersupply in the required number of geriatricians, geriatric psychiatrists, and COE physicians to meet anticipated population demand.
Risiko und HIV / Aids in Botswana
Authors: Bochow Astrid
Published: November 2020

Botswana, one of the few middle-income countries in Africa, has one of the highest HIV rates in the world. In her book Astrid Bochow deals with the Botswana middle class, which has formed since the 1980s: How do these privileged groups handle the permanent threat of infection and the experience of illness and loss? How does their everyday life in family and partnership look like? And what new social and economic opportunities open up for them in the crisis? The author analyzes the resulting political, medical and social discourses on family and health.
Integrative taxonomy reveals two new cryptic species of Hyphessobrycon Durbin, 1908 (Teleostei: Characidae) from the Maracaçumé and middle Tocantins River basins, Eastern Amazon region
Authors: Guimarães Erick Cristofore , De Brito Pâmella Silva , Bragança Pedro Henrique Negreiros , Santos Jadson Pinheiro , Katz Axel Makay , Carvalho Costa Luis Fernando , Ottoni Felipe Polivanov
Published: November 2020

Two new species, Hyphessobrycon frickei Guimarães, Brito, Bragança, Katz & Ottoni sp. nov. and H. geryi Guimarães, Brito, Bragança, Katz & Ottoni sp. nov., are herein described, based on seven different and independent species delimitation methods, and on molecular and morphological characters, making the hypothesis of these new species supported from an integrative taxonomy perspective. They belong to the “Rosy tetra” clade, which is mainly characterized by the presence of a dark brown or black blotch on the dorsal fin and the absence of a midlateral stripe on the body. These two new species are distinguished from the other members of this clade mainly by the arrangement, shape and color pattern of humeral and dorsal-fin spots, as well as by other characters related to scale counts and body pigmentation. The placement of the new species within the “Rosy tetra” clade was based on the combination of morphological character states mentioned above and corroborated by a molecular phylogenetic analysis using the mitochondrial gene cytochrome oxidase subunit 1. In addition, a new clade (here termed Hyphessobrycon copelandi clade) within the “Rosy tetra” clade is proposed based on molecular data, comprising H. copelandi, H. frickei sp. nov., H. geryi sp. nov. and a still undescribed species. Our results corroborate the occurrence of hidden species within the “Rosy tetra” clade, as suggested by previous studies.
COVID-19 RISK ASSESSMENT IN PUBLIC TRANSPORT USING AMBIENT SENSOR DATA AND WIRELESS COMMUNICATIONS
Authors: Senturk Izzet Fatih , ADAR Nurettin Gökhan , Panić Stefan , Stefanović Časlav , Yağanoğlu Mete , Prilinčević Bojan
Published: November 2020

Covid-19 causes one of the most alarming global health and economic crises in modern times. Countries around the world establish different preventing measures to stop or control Covid-19 spread. The goal of this paper is to present methods for the evaluation of indoor air quality in public transport to assess the risk of contracting Covid-19. The first part of the paper involves investigating the relationship between Covid-19 and various factors affecting indoor air quality. The focus of this paper relies on exploring existing methods to estimate the number of occupants in public transport. It is known that increased occupancy rate increases the possibility of contamination as well as indoor carbon dioxide concentration. Wireless data collection schemes will be defined that can collect data from public transportation. Collected data are envisioned to be stored in the cloud for data analytics. We will present novel methods to analyze the collected data by considering the historical data and estimate the virus contagion risk level for each public transportation vehicle in service. The methodology is expected to be applicable for other airborne diseases as well. Real-time risk levels of public transportation vehicles will be available through a mobile application so that people can choose their mode of transportation accordingly.
INFLUENCE OF L-CYSTEINE AND N-ACETYL-L-CYSTEINE ON REDUCING ACTIVITY OF THIOUREA DIOXIDE IN AQUEOUS SOLUTIONS
Authors: Makarov Sergei V. , Pokrovskaya Elizaveta A. , Salnikov Denis S. , Amanova Anastasiya V.
Published: November 2020

The influence of L-cysteine and N-acetyl-L-cysteine on the stability and reducing activity of thiourea dioxide (NH2)2CSO2 (TDO) in the reaction with azo dye Orange II has been studied. The addition of L-cysteine and N-acetyl-L-cysteine leads to the increase in reducing activity of TDO in weakly acidic, neutral and weakly alkaline solutions, but does not influence its reducing activity in strongly alkaline solutions. In alkaline solutions, the rate of reduction of Orange II is increasing, but the influence of additives of thiol acids is decreasing. The activating effect of N-ace-tyl-L-cysteine is weaker than the effect of L-cysteine, that can be explained by the differences of pKa of these acids. Indeed, the reducing activity of thiols depends on the concentration of thiolate-ions in solutions. Since pKa of cysteine (8.30) is significantly less than pKa of  N-acetyl-L-cysteine (9.52), concentration of thiolate-ions in cysteine solutions is higher. Therefore, reducing activity of L-cysteine is higher.  The influence of L-cysteine and N-acetyl-L-cysteine on the reaction of TDO with Orange II is different from the influence of aminoacid glycine: in neutral solutions glycine decreases the rate of reaction. The interaction of TDO with L-cysteine in weakly acidic, neutral and weakly alkaline solutions is accompanied by the oxidation of L-cysteine to cysteinesulfenic acid and reduction of TDO to thiourea monoxide (NH2)2CSO. Then cysteinesulfenic acid reacts with L-cysteine with formation of cystine. The reaction studied here is the first example of reduction of TDO by sulfur-containing compounds.
SPECTRAL PROPERTIES OF ZINC AND COBALT MESO-TETRAPHENYLPORPHYRINS IN POLYMER FILMS
Authors: Glazkova Maria Е. , Petrova Maria V. , Rodina Yuliya S. , Rodina Sofia S. , Аgeeva Тatiana А.
Published: November 2020

The results of studying the spectral properties of zinc and cobalt meso-tetraphenyl-porphyrins included as the modifiers in polymethylmethacrylate, polystyrene and polyvinylchloride films are presented in this article for the first time. It was established that an inert polymer matrix of polyvinylchloride, block polystyrene and polymethylmethacrylate does not affect the spectral properties of tetrapyrrole macroheterocycles, which are included in it. In this case, insignificant bathochromic shift of the absorption bands of the metal complexes in the modified films is recorded, which is probably due to the presence of intermolecular interaction of the metalloporphyrin with the polymer matrix. The method of polymer producing is important for modification of polystyrene or polymethyl methacrylate films. The ignificant changes are observed in the electronic spectra of metalloporphyrins due to the interaction between the modifier and the residual amount of the radical polymerization initiator (benzoyl peroxide) used in the preparation of polymers. Earlier studies showed that the interaction of benzoyl peroxide with zinc and cobalt meso-tetraphenylporphyrinates in solution leads to the formation of the corresponding metalloisoporphyrinates. In this work, the possibility of such structures formation in a polymer matrix is shown for the first time. In this case, in the electronic absorption spectra of the modified films, as in solutions, bands appear in the near IR region. The fluorescent properties of modified films have been studied. It was shown that in the absence of interaction between the components in the film, metalloporphyrins introduced into the polymer matrix retain their ability to fluorescence.
ON REACTIVITY OF PIPERAZINE AMINOGRUPS IN INTERACTION WITH ETHYLENE OXIDE
Authors: Demidova Yuliya V. , Potekhin Vyacheslav V. , Demidov Pavel A.
Published: November 2020

Currently, the main method for producing N-(2-hydroxyethyl) piperazine in industry is the cyclization of ethylene glycols and ethanolamines in the presence of ammonia and hydrogen. The main disadvantage of this method is the production of a wide range of products and, as a consequence, low selectivity for N-(2-hydroxyethyl) piperazine. In this work, the object of study is the piperazine hydroxyethylation reaction in the presence of an “inert” solvent under the reaction conditions, as the most selective way to obtain N-(2-hydroxyethyl) piperazine. The solvent molecule acts as a homogeneous catalyst of the acid type and is characterized by the presence of a mobile proton for opening the oxirane ring of ethylene oxide by the acid-base mechanism. There was studied the dependence of the yield of reaction products on the parameters of the process in the temperature range of 60 - 130 ° C; solvent concentration (water, methylcellosolve) 1 - 75% wt. and molar ratio of reagents (ethylene oxide / piperazine) 0.2 - 1. Analysis of the reaction mass by gas-liquid chromatography showed that the main by-product is N, N'-bis (2-hydroxyethyl) piperazine - the product of the hydroxyethylation of N-(2-hydroxyethyl ) piperazine in the second amino group. The hydroxyl group of hydroxyethylation products are formed in a negligible amount. It was found that the composition and concentration of the solvent, as well as the temperature regime of hydroxyethylation, do not significantly affect the selectivity of the process. It was shown that piperazine hydroxyethylation is described by the kinetics of series-parallel reactions. The results obtained in the study may be of interest for the development of piperazine hydroxyethylation process technology, in terms of simplifying the mathematical model of the reactor unit by excluding from the description factors that do not significantly affect the selectivity of the formation of N-(2-hydroxyethyl) piperazine.
EFFECT OF NANOCARBON ADDITIVES ON STABILITY OF POLYMER COMPOSITES
Authors: Zeynalov Eldar B. , Agaguseynova Minira M. , Salmanova Nazila I.
Published: November 2020

This review briefly describes a state of research on the effect of fullerenes and carbon nanotubes (CNTs) on a durability of various polymer composite materials under extreme conditions. Fullerenes C60, C70, fullerene soot and CNTs integrated into the polymer matrix effectively prevent both thermal and thermo-oxidative degradation, as well as photo-oxidation processes. The stabilization mechanism of the carbon nanocompounds (CNC) is likewise and consists of the substantial end-capping termination of oxidation destructive chains on the nanocarbon skeleton. At that, the data array unequivocally indicates the predominant addition of carbon-centered alkyl radicals. Various polymer composite materials based on polyolefins, polyacrylates, polyamides, polycarbonates, elastomers are involved into the consideration. The approaches described are mostly aimed to increase the level of stabilizing activity of the polymer composites using different combinations of nanocarbon additives. The optimal dosage of CNC and interfacial compatibility between the polymer and fillers can significantly increase the heat resistance of the composites. The replacement of carbon atoms in the fullerene molecule with heteroatoms can also change its electronic properties and improve the antiradical and antioxidant activity. Areas for the effective use of fullerene C60 in aqueous media can be significantly expanded by modification with hydrophilic polymers. Thus, the performance of CNC integrated in the polymer composites is similar with those for strong synthetic stabilizers. CNC have good prospects for real industrial applications.
MODIFICATION OF DIAMOND SURFACE DURING PHOTOLITHOGRAPHY, PLASMA-CHEMICAL CLEANING, AND MAGNETRON DEPOSITION
Authors: Golovanov Anton V. , Luparev Nicolay V. , Sorokin Boris P.
Published: November 2020

An influence of the conventional planar technology of the semiconductor surface treatment operations (photolithography, plasma-chemical surface cleaning in radio frequency low-pressure oxygen discharge, and thin metal films growth) on monocrystalline diamond surface topography and roughness is investigated. It is preliminary shown that photolithography without the plasma cleaning and magnetron deposition of an aluminum film do not induce any diamond surface changes which could be found by the optical profilometry, electron and optical microscopy. However, as a result of the lithography some organic contaminants can decrease the adhesion of the aluminum film and have to remove from the surface. Further, the influence of the above-listed surface treatment operations separately and in combinations on the synthetic diamond surface is investigated. It is found that an even short oxygen plasma cleaning during 5 min with a low bias power of 20 W leads to etching the grooves on the diamond surface The depth of the etching grooves varies by more than an order of magnitude in different experiments (0.3 - 19 nm), and by 10-20% within the same substrate under the influence of the poorly controlled external factors. Also, oxygen plasma treatment changes its secondary electron emission coefficient. Deposition of aluminum film after plasma cleaning does not induce noticeable changes in the diamond surface topography. The quality of diamond surface polishing (in “hard” of “soft” direction), the diamond’s type (IIa or IIb) as well as producing method (HPHT or homoepitaxial CVD) do not affect the result of grooves formation.
SYNTHESIS AND PROPERTIES OF ION EXCHANGERS DERIVED FROM NON-WOOD CELLULOSE
Authors: Yelatontsev Dmitry A. , Mukhachev Anatoly P.
Published: November 2020

A rational scheme for the processing of large-scale agro-industrial waste – walnut shells Juglans Regia L. and apricot kernels Prunus Armeniaca L. was proposed. At first stage, the raw material was delignificated using liquid ammonia to remove hemicelluloses and lignin. Isolated non-wood pulp is chemically modifying to increase sorption and ion exchange properties. For the synthesis of anion exchangers, cellulose was aminated using pyridine or trimethylamine after preliminary treatment consequentially with formalin and C2H5OH in HCl medium. As a result, we obtained high and weakly-basic ion exchangers with nitrogen content of 10.3–11.5% and high exchange capacity towards various classes of inorganic anions. For synthesis of cation exchangers, cellulose was treated with solution consisting of 20% H3PO4, 40% CO(NH2)2, and 40% H2O. Consequently, we obtained phosphorus-containing high-acidic cation exchangers with exchange capacity towards heavy metal of 5.5–8.6 mmol∙cm–3. Both types of ion exchangers have a high capacity towards uranium: anion exchanger – 4.25 mmol∙cm–3 and cation exchanger – 4.94 mmol∙cm–3, respectively. Average total yield of ion exchangers related to weight of air-dry feedstock was 90%. Synthesized ion exchangers characterized by IR spectroscopy. Presence of amine functional groups –NH2 in aminated cellulose and phosphate ester groups –OPO(OH)2 in phosphorylated cellulose was established. Specific surface area and total static exchange capacity of synthesized ion exchangers were established. An environmentally friendly method for the disposal of spent solutions from the synthesis of cation exchangers was proposed. It allows getting a liquid complex fertilizer containing 17% N and 13.9% P2O5. Usage of this fertilizer for grain crops feeding increases plants length by 40–75%, as well as overall biomass increase by 20–30%.
ELECTRODEPOSITION OF COPPER IN ULTRASONIC FIELD FROM SPENT ETCHING SOLUTIONS
Authors: Larionova Maria P. , Solovieva Nina D. , Savelieva Elena A.
Published: November 2020

It is studied the regeneration and utilization possibility of spent nitric acid solutions for copper and its alloys etching for the creating an environmentally clean closed-cycle production of regenerated electrolytes. It is established that some difficulties arise when using the electrochemical method in the regeneration process of these solutions: during copper electrodeposition from spent copper-containing nitric acid solutions, nitric acid decomposes with vigorous evolution of nitrogen dioxide, which prevents copper ions reduction. In order to suppress the side process, it was proposed to partially neutralize the solution, not reaching the pH of copper hydration (pH 4-5). It is revealed that a decrease in the concentration of metal cations occurs due to partial neutralization of the nitric acid contained in the solution by concentrated alkali solution. The pulsed electrolysis mode was used to increase the efficiency of the metal ions electrodeposition process from dilute solutions. It is established that the using of pulsed electrolysis can reduce diffusion difficulties that arise in a dilute spent nitric acid copper-containing solution, thereby intensify the process of copper electrodeposition. It is showed that the prospects of using ultrasound to increase the rate of the copper electrodeposition process and improve the quality of the resulting coating. It is studied the ultrasound field effect on nucleation during copper electrodeposition in a pulsed mode from a partially neutralized electrolyte simulating the spent nitrate solution of etching copper alloys on various materials by the potentiostatic. It is established an increase in the number of copper nucleus that form on the studied substrates (graphite, copper, steel) at the initial time under the action of an ultrasonic field. It is concluded that the use of ultrasound allows to intensify the process of metal electrodeposition. An increase in current efficiency during copper electrodeposition and an increase in the copper extraction degree using ultrasonic field are achieved at lower cathodic current densities in a pulse. It is substantiated using of graphite foil and steel as cathode materials in the copper extraction from the spent nitric acid etching solution.
KINETIC FEATURES OF PLASMA-CHEMICAL MODIFICATION OF POLYCARBONATE IN PLASMA IN ARGON - OXYGEN MIXTURE
Authors: Shikova Tatyana G. , Smirnov Sergey A. , Artyuhov Alexey I.
Published: November 2020

This paper presents the results of experimental study of the processes of destruction and changes in the composition of the surface layer of a Lexan 8010 polycarbonate (PC) film during treatment in a positive column of a DC glow discharge in argon, oxygen, and their mixtures. The mass loss rates of the polymer samples were measured depending on the parameters of the discharge and the composition of the plasma-forming gas. The IR spectra of the polymer films after plasma exposure were analyzed. It was shown that the most noticeable changes in the sample destruction rate and the chemical composition of the surface layer occur when the oxygen content in the mixture is up to 20%. With a further increase in the O2 content in the plasma-forming mixture, the changes are insignificant. The main gaseous products of PC destruction in the plasma of an argon-oxygen mixture are H2, CO, and H2O molecules. In the first second after the discharge is turned on, H2 molecules are released at maximum rate and at a lower CO rate. The formation of carbon monoxide and hydrogen molecules occurs without the direct participation of oxygen under the action of active particles of argon plasma without the participation of active oxygen. Exposure to argon plasma leads to an increase in the oxygen content on the sample surface. In this case, the destruction of С – О, О–С(=О)–О bonds, which are part of the structure of the polycarbonate elementary unit, and the formation of new oxygen-containing bonds are observed. Etching of the polymer with active plasma particles leads to a change in the micro relief of the sample surface. A change in roughness and an increase in the concentration of polar functional groups increases the wettability of the PC film surface. A discussion of the possible mechanisms of the processes is made, which allows us to describe the observed results.
AGGREGATION OF MS-MONOPYRIDYL-Β-OCTAALKYLPORPHYRINS IN DICHLOROMETHANE IN PRESENCE OF Pd(II)
Authors: Ivanova Yulia B. , Mamardashvili Nugzar Zh. , Kochkina Natalya E.
Published: November 2020

Aggregation of 13,17-diethyl-2,3,7,8,12,18-hexamethyl-5-(pyridin-4-yl) porphyrin (I), 13,17-diethyl-2,3,7,8,12,18-hexamethyl-5-(pyridin-3-yl)porphyrin (II) and 13.17-diethyl-2,3,7,8,12,18-hexamethyl-5-(pyridin-2-yl)porphyrin (III) in the presence of trans-bis(benzonitrile)palladium(II) dichloride was studied by dynamic light scattering and electronic absorption spectroscopy in dichloromethane at 293 K. The average aggregate size and the nature of their distribution were determined. Using scanning electron microscopy, it was determined the size and composition of clusters formed by aggregates of complexes of the palladium(II) cation with the studied porphyrins. It was shown that minimal acetic acid additions lead to the destruction of the corresponding clusters. At the same time, complete destruction of the aggregates does not occur even with a 100-fold molar excess of acid.We used the Zetasizer Nano ZS (model ZEN3600, Malvern Instruments), equipped with a 633nm laser and non-invasive backscattering (NIBS) technology when the scattered light detector is positioned at an angle of 173° to the incident light. Confirmation of porphyrin aggregation was performed by additional study of the structure using a Hitachi TM4000Plus desktop electron microscope equipped with a 4-segment highly sensitive semiconductor detector and a secondary electron detector for low vacuum mode. Elemental analysis of the obtained aggregates in the cluster was performed using a silicon drift detector with a working area of 30 mm2, combined with a Hitachi TM4000Plus microscope. It was found that aggregates consisting of a para-pyridyl derivative of alkylporphyrin and trans-bis (benzonitrile) palladium (II) dichloride are formed in dichloromethane at 293 K. The best results of porphyrin structures were observed for mixtures of 13,17-diethyl-2,3,7,8,12,18-5-hexamethyl-5-(pyridine-4-yl)porphyrin with TRANS-bis(benzonitrile)- palladium (II) dichloride in a ratio of 1:3, which is probably due to less spatial shielding of the reaction center of the macrocycle and, as a result, better stabilization of the resulting particles. The size of a cluster consisting of individual aggregates was measured using scanning electron microscopy. An elemental analysis of a single aggregate was obtained.
RESEARCH OF OPERATIONAL AND DYNAMIC PROPERTIES OF RUBBER FOR PRODUCTS WORKING IN SEA WATER
Authors: Egorov Evgeniy N. , Kol'tsov Nikolay I. , Ushmarin Nikolay F. , Sandalov Sergey I.
Published: November 2020

The article studies the effect of trans-polynorbornene, general and special-purpose rubbers and fillers on the vulcanization characteristics of a rubber mixture, physical, mechanical, operational and dynamic properties of vulcanizates based on butadiene methylstyrene caoutchouc. The investigated model rubber mixture included SKMS-30ARK rubber, sulfur, 2,2'-dibenzthiazole disulfide, guanide F, zinc white, stearic acid, phenyl-2-naphthalamine, N-isopropyl-N'-phenyl-para-phenylenediamine, carbon blacks of grades P 514 and N 220, shungite powder and other ingredients. The rubber mixture was produced on laboratory rolls LB 320 160/160. The first (basic) version of the rubber mixture contained industrial oil I-12A as a softener. The second version of the mixture contained a modifying additive based on trans-polynorbornene and industrial oil I-12A. The third, fourth and fifth versions were prepared on the basis of a combination of rubbers SKMS-30ARK, SKN-4065 and BK-1675, including a modifying additive, as well as polyisobutylene P-118 and sevilen 11808-340. The vulcanization characteristics of the rubber mixture were studied on an MDR 3000 Basic rheometer at 150 °C for 30 min. To determine the physical and mechanical properties of rubber, standard samples of all variants of the rubber mixture were vulcanized at a temperature of 143 °C for 30 min in a vulcanization press of the P-V-100-3RT-2-PCD type. Studies of the physical, mechanical, operational and dynamic properties of rubber were carried out in accordance with the existing standards for the rubber industry. It is shown that vulcanizates containing a modifying additive have lower values of conventional tensile strength, hardness and tear resistance compared to vulcanizate of the base version of the rubber mixture and are characterized by increased dynamic and performance properties. Rubber containing a combination of butadiene-nitrile, butadiene-methylstyrene caoutchoucs and butyl caoutchouc, 10.0 mass parts sevilen 11808-340, 20.0 mass parts of trans-polynorbornene composed of in the modifying additive and 55.0 mass parts of carbon black P 324, possesses improved physical, mechanical and dynamic properties, as well as high resistance in sea water.
Assessment of the nitrogen status of park forest ecosystems by phytoindication
Authors: Miroshnyk N. V.
Published: November 2020

Aim. The aim is to assess the changes in the nitrogen regime of park ecosystems in Kyiv by tiers due to the supply of nitrogen with atmospheric precipitation. Methods. Applied methods of forestry, geobotany, phytoindications. Results. We have analyzed the number of nitrophilic stenobionts of woody vegetation and grass cover. The eutrophication trend is the same for both tiers of the studied ecosystems. Although in the grass cover the proportion of nitrophils is greater than in the woody one. In the natural boundary Lysa Gora nitrophil content is the highest among the studied ecosystems of the park (70% in the grass cover, 58.3% in the woody vegetation). Conclusions. Thus, 50% of the parks are in critical danger, 30% are in a threatened state, only the Pushcha-Voditsa parks are in a stable condition. A significant number of nitrophilic stenobiots were found in Kyiv parks (50–70%), and the grass cover is more plastic in terms of environmental changes than the tree.

Keywords: eutrophication, park ecosystems, nitrophils, stenobionts, urban ecosystem.
The effect of blue and red light on physiological and biochemical characteristics of wheat plants
Authors: Azizov I. V. , Gasymova F. I. , Ibragimova U. F. , Tagiyeva K. R. , Abdullayeva A. B.
Published: November 2020

Aim. The effect of blue and red light on the activity of catalase and ascorbate peroxidase, the content of proteins and soluble carbohydrates in the leaves of wheat varieties under the action of sodium chloride were investigated. Methods. The objects of research were bread wheat Saratovskaya-29 (Triticum aestivum L.) and durum wheat Barakatli-95 (Triticum durum Desf.). Plants were grown in laboratory conditions in an aqueous medium using a Knoop nutrient medium. Experimental plants were coated with transparent films transmitting light at wavelengths of 420-480 nm (blue light) and 640-680 nm (red light). During the growing season, samples of fully formed leaves were taken for physiological and biochemical studies every week at 11 a.m. Results. Under the action of sodium chloride, the accumulation of hydrogen peroxide in white light was higher than in blue and red light (table). Low catalase activity was also observed in blue and red light under the influence of sodium chloride in both varieties. In bread wheat variety Saratovskaya -29 level of hydrogen peroxide, the activity of catalase and ascorbate peroxidase enzymes was lower than that of the Barakatli-95 durum wheat variety. Conclusions. Blue light stimulated the synthesis of proteins, while red light stimulated the synthesis of carbohydrates. Blue and red light prevented the formation of H2O2 under the influence of NaCl.

Keywords: blue light, red light, catalase, ascorbate peroxidase, proteins, carbohydrates.
The effect of mutations in the alleles Gli-B1b and Gli-B1l on grain quality indices of common wheat
Authors: Kozub N. A. , Sozinov I. O. , Bidnyk H. Ya. , Demianova N. O. , Sozinova O. I. , Blume Ya. B.
Published: November 2020

Aim. The aim of this study was to analyze quality indices in mutants at gliadin loci developed on the basis of the common wheat cultivar Bezostaya 1. Methods. Acid polyacrylamide gel electrophoresis and SDS-electrophoresis of storage proteins were performed to check mutations. Grain quality indices (SDS sedimentation volume, grain hardness, seed plumpness, and grain protein content) were analyzed: Results. Both mutants at Gli-R1 with the intensified secalin component and with the changed mobility of the secalin component showed lower grain hardness in comparison with the respective non-mutant lines. The mutation of the allele Gli-B1b causing the absence of synthesis of the g-gliadin and the minor w-gliadin resulted in the decrease in grain hardness and in the increase in the SDS-sedimentation volume. Seeds of the Gli-B1b mutant with the absence of synthesis of the major w-gliadin were less plump and showed higher protein content than in the non-mutant line. Conclusions. The effects of mutations of the allele Gli-B1b associated with the absence of certain gliadin components and Gli-R1 mutations on grain quality indices were revealed.

Keywords: Triticum aestivum, gliadins, secalins,  SDS-sedimentation, grain hardness.
Yield capacity and grain quality of productive Triticum aestivum L. mutants, induced by chemical mutagenic factors of the environment
Authors: Morhun V. V. , Yakymchuk R. A.
Published: November 2020

Aim. Taking into account the fact that the zones of local massive chemical soil contamination could have unique conditions of the effect of gene-toxic factors on living organisms, the purpose of the research was to study yield capacity and some parameters of grain quality of productive T. aestivum L. mutants, induced by chemical techno-genic mutagenic factors of the environment. Methods. The yield from each plot was determined based on three-year data. The determination of the total protein and gluten content and the studying of the indicators of grain firmness were carried out in M6 by the method of infra-red spectroscopy (NIR). Gluten quality was determined by sedimentation indicator SDS-30. Results. Samples were selected whose yield exceeded the initial form by 1.2–9.0%. In most of them by the content of protein and gluten in grain, the indicator of sedimentation and grain firmness corresponds to the level of an initial form or does not equal it considerably. Mutant sample No. 5561 of cultivar Albatros odeskyi, induced by the contamination with the discharges of Burshtyn ThPS, was found; its yield capacity was supplemented by a serious increase of grain quality indicators. Conclusions. Using the effect of chemical techno-genic mutagenic factors of the environment, it is possible to improve the indicators of wheat yield capacity and grain quality. The expansion of the genetic diversification of the initial breeding material due to a gene-toxic effect of xenobiotics creates perspectives for its use to implement breeding-genetic programs of the improvement of wheat cultivars.

Keywords: Triticum aestivum L., mutagenic factors, productive mutants, yield capacity, grain quality.
Genetic analysis of oleic acid content in the oils of maize mutants amylose extender
Authors: Tymchuk D. S. , Potapenko H. S. , Tymchuk N. F. , Torianyk I. I.
Published: November 2020

Aim. Genetic analysis of oleate content in the carriers of maize mutation ae. Methods. In two-year experiments 10 unrelared on origin inbreds – carriers of ae mutation and a series of hybrids from their diallel and top-cross crossings were analysed. The analysis of the fatty acid composition of oil was carried out using a modified gas-chromatographic Peysker method. Results. It was found that the carriers of maize ae mutation are characterized by a higher oleate content compared to the maize of common type, however the oleate content in the oils of  ae mutants was lower than that of the mutants su1 and su2. The different inbreds – carriers of the ae mutation differed among themselves by the the effects of the combining abilities for the oleate content in oil. The inheritance of oleate content by hybrids based on the ae mutation was similar to the type of incomplete dominance with a significant contribution of additive effects to the variance. Conclusions. In the carriers of ae maize mutation, the spatial linkage in the fifth chromosome of ae mutant gene with the oleate – encoding locus, the effect of which is modified by the polygenic complex, is likely.

Keywords: Zea mays L., mutation ae, oleic acid, genetic analysis.
Identification of homogeneous forms of winter wheat under controlled conditions by the cluster analysis method
Authors: Tishchenko V. N. , Husenkova O. V. , Batashova M. E. , Kolesnik A. V. , Dubenetc N. V.
Published: November 2020

Aim. The purpose of the research is to identify the best genotypes of winter wheat balanced by quantitative characteristics and productivity by three sowing dates. Methods. Structural analysis of plants, mathematical and statistical analysis, cluster analysis. Results. For four years the Govtva winter wheat variety and lines (Peremoha 2 × Kolomak 5) × Stanichnaya, (Peremoha 2 × Kolomak 3) × Stanichnaya were in the best groups of the best clusters at different sowing dates. The line (Peremoha 2 × Kolomak 3) × Zernohrad 11 during 2013-2015 formed high indicators of signs of productivity and prolificness. Such varieties of winter wheat as Samara-2, Sanzhara, Radivonovka, lines - Lord × Manzhelia, Lord × Krizhinka, which for two years in a row (2015-2016) were concentrated in the best groups of the best clusters for all sowing dates, can be used as the initial breeding material. Conclusions. As a result of studies which were held in 2013-2016, winter wheat genotypes were identified which form a high level of quantitative traits and yield regardless of the sowing date, which can be used as parent forms for creating highly productive varieties of winter wheat.

Keywords: winter wheat, signs, productivity.
The formation of muscle tissue and its quality in wild and domestic pigs
Authors: Khokhlov A. M. , Baranovskyi D. I. , Danilova T. M. , Fediaeva A. S.
Published: November 2020

Aim. The aim of the study is to determine the peculiarities of muscular system formation of wild European wild boar body (Sus scrofa ferus) in comparison with modern basic breeds of pigs: large white, large black and north Caucasian, which have both theoretical and practical value. Methods. Objects of research – piglets and adult animals of European wild boar and domestic animals. Our task is to study age-related changes of growth and development of individual muscle groups in piglets of large white breed and Sus scrofa ferus piglets at 50-70 days of age, as well as to research the physicochemical properties of muscle tissue due to domestication of pigs. Results. Domestication of pig is a complex process. European wild boar has been the genetic base of breed formation process in Europe over the past 10-12 thousand years. The main role in this process belongs to such genetic mechanisms as mutation, recombination, heredity, variability and selection. Studies have established that one of domestication regularities of muscular system in animals is the result of artificial selection at each stage of animal ontogenesis. Conclusions. Exterior-constitutional changes in the proportions of pig skeleton have occurred in the process of pigs domestication and selection, at a ratio of mass of individual muscle groups. It was found that during domestication and selection of pigs, the proportion of muscles of pelvic limb and sacral spine increases, the quality of meat changes.

Keywords: domestication, species, ontogeny, breed, genotype.
Association of PPARG and PPARGC1 polymorphism with effectiveness of exercise-induced fat mass loss
Authors: Mazur Iu. Iu. , Drozdovska S. B. , Andrieieva O. V. , Vinnichuk Yu. , Polishchuk A. , Andreev I. O. , Dosenko V. Ye. , Pickering C. , Ahmetov I. I.
Published: November 2020

Aim. Peroxisome proliferator activated receptor gamma (PPARG) and PPARG coactivator 1α (PPARGC1A) is a key regulator of energy metabolism. This study examines the influence of PPARG and PPARGC1A gene polymorphisms on the PPARG expression, obesity risk, lipoprotein profile and effectiveness of the physical activity intervention for improvement of these parameters. Methods. 39 women with BMI>30 kg/m2 participated in the three-months fitness-program and followed a hypocaloric diet (1500 kCal). At the beginning and at the end of the program, the following anthropometric and biochemical parameters were measured: BMI, percentage of total and visceral fat, amount of plasma lipoproteins, cholesterol, and triglycerides. Single nucleotide polymorphisms were identified in PPARG (n=94) and PPARGC1A (n=138) genes. PPARG mRNA expression was measured through reverse transcription PCR. Results. The physical exercise intervention resulted in a significant fat mass loss in all participants (40.3±5.3% before the study vs 36.4±5.7% after the study, P<0.00001). Polymorphisms rs6442311, rs6846769, rs6846769 were associated with lower visceral fat percent, rs6442311 also correlated with PPARG expression. PPARGC1A polymorphisms rs4458444, rs2305681 were associated with plasma lipoproteins, cholesterol, and triglyceride content. Weight loss effectiveness was connected with rs17650401, rs9833097, rs12629751. Conclusions. After correction for multiple comparisons only rs17650401, of PPARGC1A gene was associated with more effective fat mass reduction.

Keywords: PPARG, obesity, single nucleotide polymorphism, weight loss, exercise intervention.