bluuebunny/crossref_metadata_2025 huggingface dataset:
Câteva consemnări cu privire la contactele culturale dintre Imperiul roman şi teritoriile de la nord de Dunărea de jos în perioada romană târzie / Several contributions concerning the cultural contacts between the Roman Empire and the territories located north of the Lower Danube during the late Roman period
Authors: Alexandru Popa
Published: February 2021

The study discusses the challenges of interpreting the functionality of those edifices built in Roman style, found however outside the provincial borders, in particular the contribution of such buildings to the identification and interpretation of contacts between the Roman Empire and its northern neighbours, in the area of the Lower Danube, their identities, interests and experiences. The analysis is grounded on the archaeological features and contexts encountered in the middle 4th c. AD site of Sobari (Republic of Moldova) on the Middle Dniester, resuming a previously explored situation, to which new data, emerging from recent excavations and geophysical investigations can be added.
Of remarkable size for its age and cultural environment, the settlement at Sobari spreads on 30 ha. A part of it was, at one point, enclosed with a stone wall, built with paraments. Inside this enclosed space there was found a rectangular construction (18 x 10 m), with 1 m deep foundations, built of stone, bricks and mortar, covered with tegulae, part of which bared production stamps known in the Roman Empire. Fragments of glass suggest the existence of at least one window, while 16 column bases can be surely connected with a peristyle. These architectural details are completely out of place north of the Lower Danube, while the found inventory is surprisingly local, typical Sântana de Mureș-Černjachov. No heating installation was yet found. While a military role for the site is excluded, as it is located 300 km north of the closest Roman power centre, thus isolated, unable to support a defensive system, several other functionalities are in turn explored: a temple or the residence of a Roman citizen. The most reasonable interpretation is considered the one which treats the complex in Sobari as built by an experienced architect commissioned by a local aristocrat who had direct contacts with the Roman world, for example as a trader, a hostage, a soldier or an envoy.
Ecohydrological monitoring of the river habitat quality
Authors: Matoušková Milada
Published: February 2021

Complex ecohydrological methods are of principal significance when evaluating the state of water ecosystems and they give also decisive information for their restoration. New approaches in the evaluation allow a broader view at the water ecosystem. The ecohydrological state of a stream is determined by a set of hydromorphological characteristics of the river channel, of its runoff, by hydrochemical and hydrobiological condition of water, by the character of bank and riparian belts and transformation of the floodplain. The new European Water Framework Directive (2000/60/EC) underlines the significance of ecohydrological methods. In the paper is represented a method of ecomorphological evaluation of streams habitat quality and its application on the model study area of the Rakovnický Brook.
Nasafort in the treatment of patients with seasonal allergic rhinitis with sensibilization to weed pollens
Authors: Gogunska Inna V. , Zabolotna Diana D. , Zaritskaya Irina S.
Published: February 2021

The article presents the results of a study on the use of nasal spray Nazafort allergy protection in the treatment of patients with seasonal allergic rhinitis. The group of patients who used Nazafort in combination with levocetirezine showed a more pronounced and rapid regression of objective and subjective clinical manifestations of the disease compared with the group of patients who received only levocetirizine. The results obtained can be considered as indirect confirmation of the known data on the barrier property of Nazafort in its insufflation in the nasal cavity, which prevents contact of the allergen with the shock organ.
Evaluation of VEGF-A in relation to childhood acute lymphoblastic leukemia (in Basrah/Iraq)
Authors: Badr Zainab , AL-Moosawi Wijdan , Ali Sadiq
Published: February 2021

Background: Cancer angiogenesis demonstrates an important role in the progression and pathogenesis
of blood malignant disorders including acute lymphoblastic leukemia (ALL). Vascular endothelial
growth factor (VEGF)-A is one of the most effective elements of endothelial cell growth; it promotes
vascular permeability of endothelial cells and provides the new vasculature with oxygen and nutrients.
Higher VEGF-A levels in childhood acute lymphoblastic leukemia (ALL) is associated with poorer
patient outcomes.
Aim of the study: to assess the level of VEGF-A in plasma of children with ALL.
Subject and method: Forty children with ALL and 40 healthy children as control were enrolled in this
study conducted at the Oncology Unit in Basrah Children’s Hospital from Oct 2019 to March 2020.
Plasma VEGF-A level was evaluated using ELISA assay.
Results: The plasma level of VEGF-A is higher in ALL children than those in the control (p < 0.001).
Moreover, the plasma VEGF-A level in the high-risk group (HRG) is higher than that in the standard risk
group (SRG).
Conclusion: The significantly higher level of plasma VEGF-A in ALL children compared to the healthy
ones may demonstrate the role of VEGF-A in stimulating angiogenesis in pediatric ALL.
Keywords: Angiogenesis, vascular endothelial growth factor-A, childhood acute lymphoblastic
leukemia, acute lymphoblastic risk groups.
Development of bioactive/active additives based on essential oils: A review
Authors:   Universidad de Santiago de Chile, Alarcón-Moyano Jessica , Matiacevich Silvia ,   Universidad de Santiago de Chile
Published: February 2021

The use of bioactive/active additives has been increasing in recent years, especially those derived from medicinal plants such as essential oils. However, due to essential oil oxidation it is necessary to protect it by encapsulation techniques such as: emulsion, spray- and/or freeze-drying as the most economical techniques. On the other hand, an important factor is to determine the appropriate wall material to obtain a prolonged or controlled release in the food or in the organism. Therefore, several factors affect the release of the compounds such as the type, amount of wall material and/or combination of wall materials. Therefore, the knowledge of all the aforementioned factors is important in order to make an adequate selection for the development of a bioactive/active additive based on essential oils.
Mental Health: Breakdowns in Health Care Service throughout the Continuum of Patient Care and Recommendations for the Future
Authors: Kimberly N. Howard
Published: February 2021

This phenomonelogical work integrates the relevant literature along with a lived experience of mentalhealthcare. The article considers the role of consumers as participants in healthcare services and ascontributors to the knowledge base. The article highlights the potential for phenomonelogical studies to bebeneficial to the literature, since they can be analyzed to distinguish what, if any, similar areas exist, and asa result, what areas might be improved.
Exploring Students Nurses’ Preparedness and Readiness for to Care for Critically ILL Patients and Implication for Patient’s Safety
Authors: Amina Hemida Salem
Published: February 2021

Background: Unsafe nursing care provided to critically ill patients by unqualified nurses can cost a patient’slife. When nursing care falls short of standards because nurses are lacking knowledge and or practical skills,nursing education programs shoulder much of the responsibility.Aims: aims of the current study were to explore the students’ nurses (senior students) preparednessand readiness to care for critically ill patients, determine the students’ nurses’ perceptions toward theirpreparedness and readiness to practice as critical care nurse and, compare between the students’ nursesclinical knowledge and their self – perceptions.Method: To fulfill the aims of the study, senior students in the Faculty of Nursing at the University ofAlexandria were recruited during the last month of the internship year. Three tools were used to collect thedata. Tool one “Generation of Core Competencies” that was aimed at identifying crucial competencies thatare required for new students’ nurses to provide competent and safe patient care. Tool two “Exploring thestudents’ nurses’ preparedness and readiness to care for critically ill patients” that was aimed to exploringthe clinical knowledge of the students’ nurses (objective tool) and Tool three “Casey-Fink Readiness forPractice Survey (CFRPS)” that was aimed to determining the students’ nurses’ perceptions toward theirpreparedness and readiness to practice as critical care nurse (subjective tool).Results: Results of the current study revealed that the median knowledge score was generally low (MD:14) denoting insufficient students nurses’ knowledge. The average number of correctly answered questionsby participants was only 14 out of 50 (mean, SD 14.12, 4.03).However, the nurses’ perceptions or attitudestoward their preparedness and readiness to practice as a critical care nurse were generally positive and high.About 50% of nurses answered at least 11 questions as “strongly agree” out of 15 questions of perception.Conclusions: Although the study was conducted at the end of the internship year as the clinical internshipexperience improved the nurses’ knowledge and perceptions of readiness for practice, there was acontradiction between the student nurses’ knowledge (low) and perceptions of their readiness (high).
COMPARISON OF FUNCTIONAL OUTCOME OF DYNAMIC CONDYLAR SCREW AND CONDYLAR BLADE PLATE IN TYPE A FRACTURES OF DISTAL FEMUR IN SKELETALLY MATURUE PATIENTS
Authors: Dilshad Gill  , Muhammad Javaid Iqbal Awan  , Osma Bin Saeed  , Basharat Manzoor
Published: February 2021

ABSTRACT

BACKGROUND & OBJECTIVE: Distal femur fractures are increasingly common injuries in today’s orthopedic practice. Early treatment with suitable implant brings in promising functional outcomes. There is a growing debate over the type of implant used in these injuries. Therefore, we have compared two commonly used implants to determine the functional outcomes in search of an implant that has less post op complications, less technically demanding and produces better results. To compare the functional outcome of dynamic condylar screw with condylar blade plate in treatment of distal femur fractures.

METHODOLOGY: A total of 372 skeletally mature patients aging 18-60 years of both gender with fracture distal femur (Type A, according to OTA classification) presented within 3 weeks of fracture time were included. Patients meeting inclusion criteria were stratified into two groups having 186 patients each. Group A and Group B. Group A received dynamic condylar screw fixation and in group B, condylar blade plate fixation was preferred. Patients were followed for 3 years and their Functional outcome was evaluated with the help of Lysholm Knee Score.

RESULTS: Lysholm knee score after 3 years in group A (Dynamic condylar screw) was excellent (95-100) in 173 patients (76.9%), Good in 33 (17.7 %), Fair in 8 (4.3%), poor in 2 (1.1%).However, group B had Excellent in 57(30.6%), Good in 59(31.7%), Fair in 38 (20.4%), and poor in 32 (17.2%).

CONCLUSION: Dynamic condylar screw can be used as an effective treatment with better functional outcome as compared to condylar blade plate in type A fractures of distal femur.
EFFECTIVENESS AND SAFETY OF SOFOSBUVIR AND VELPATASVIR IN HEMODIALYSIS PATIENTS SUFFERING WITH HEPATITIS C INFECTION
Authors: Mehmood Yasir , Muhammad Imran Ashraf  , Khadija Mastoor  , Adnan Afzal  , Zafar Latif Awan
Published: February 2021

BACKGROUND & OBJECTIVE: There is scantiness of evidence-based knowledge of anti-viral therapy with sofosbuvir (SOF) and velpatasvir (VLP) in patients on maintenance haemodialysis. This report is an attempt to rationalise the safety and effectiveness of SOF and VLP in haemodialysis patients in Pakistan.

METHODOLOGY: Twenty treatment-naïve patients were incorporated in this study. Patients on maintenance haemodialysis are being administered SOF and VLP. Before initiation of treatment, all necessary investigations such as viral load, liver fibro scan, genotyping and upper GI endoscopy were made. Patients received 400 mg/day and 100 mg/day dose of SOF and VLP, respectively.

RESULTS: Mean age was 25 to 53 years; 30% were male and 70% were female as categorized. No one of these has clinical affirmation of progression of cirrhosis. The most prevalent genotype was genotype 4 that was found in 45% of cases and the second most evident was genotype 1 in 25% of cases and genotype 5 in 30% of cases. Time span of antiviral therapy was 12 weeks.

CONCLUSION: SOF and VLP based direct antiviral agents were effectual, puissant and were aptly tolerated in patients on MHD. This drug combination was well tolerated in haemodialysis patients. Not a single patient discontinued this combination therapy due to severe complications.
THE ASSESSMENT OF EMOTIONAL INTELLIGENCE IN MEDICAL FACULTY WORKING AT POONCH MEDICAL COLLEGE (PMC), AJK
Authors: Akram Zareena , Ahsan Sethi  , Aabish Mehreen  , Marium Sohail
Published: February 2021

ABSTRACT:

BACKGROUND & OBJECTIVE: There has been limited understanding of role of emotional intelligence in education and also limited understanding of emotional intelligence levels in teaching and clinical practice. The aim of the current study is to investigate the level of emotional intelligence in medical teachers and see whether emotional intelligence differs in male/female and senior/junior faculty.

METHODOLOGY: A cross sectional survey was conducted at Poonch Medical College (PMC), Rawalakot, AJK for 2 months i.e. July to August 2018. Faculty (n=117) from basic pay scale-17 to 21, of basic and clinical sciences departments were included in study after informed consent. Data were collected using “Leadership Toolkit Emotional Intelligence Questionnaire.” Descriptive and inferential statistics were calculated to measure the level of emotional intelligence in faculty members and to quantify variations across gender and position.

RESULTS: The response rate in this study was (92.3%) 108/117. There were 56 (51.9%) female and 52 (48.1%) male respondents. Majority of the faculty members 69 (63.9%) were junior level teachers whereas 39 (36.1%) were senior level faculty. The overall mean emotional intelligence was 178.4 ± 21.4, which did not vary across male, and females, or level positions. Self-awareness, was found higher in females (39.9 versus 38.2), however this difference was statistically insignificant (p-value, 0.12). The mean score in managing emotions were also slightly higher in females (33.1 versus 32.5).

CONCLUSION: The medical faculty at PMC, AJK has a reasonably high level of emotional intelligence. There was no difference in the overall emotional intelligence levels across gender and position.
Sorbent based on chitosan and polyurethane foam for cleaning aqueous media from metal ions and dyes
Authors:   Kazan National Research Technological University, Quynh Anh Quyen Thi , Zenitova Lyubov A. ,   Kazan National Research Technological University, Nghia Ngo Hong ,   Kazan National Research Technological University
Published: February 2021

This article touches upon an urgent subject at present – the development of a sorbent for purifying water resources from metal ions and dyes. For these purposes, a sorbent based on polyurethane foam filled with 30% chitosan was developed to eliminate oil spills. It is well known that chitosan is an effective absorber of metal ions, it is recommended to use chitosan for metal ions extraction from waste waters of galvanic, mining, processing and textile industries. In this purpose, it is important to research which extent of the sorbent be developed, for oil spills treatment, and have metal ions absorbability. Unfilled polyurethane foam has been studied to use as a sorbent for metal ions previously, this research shown that they are not suitable sorbents for these purposes. In order to develop a versatile sorbent, a study to combine the ability to absorb oil and oil products of polyurethane foam and the ability to purify water from metal ions and dyes of chitosan has been carried out. The best degree of purification by the sorbent is observed at a concentration of Cu2+ ions of 100 mg/l and Pb2+ ions of 200 mg/l. In addition, the sorbent is proved to be effective to a dyes of 500 mg/g concentration for their removal from aqueous solutions. Sorption isotherms according to the Langmuir and Freundlich models have high confidence coefficients – R2 > 0.87. Equilibrium parameters (RL) for Langmuir isotherms are in the range of 0 < RL < 1. The process of sorbents adsorption for both Cu2+, Pb2+ ions and dyes is satisfactorily described by both the Langmuir and Freundlich isotherms. Low values of E and G indicate the occurrence of predominantly physical adsorption in all the cases studied. It has been established that the developed sorbent, which is a specific sorbent for cleaning water surfaces from oil pollution, also allows to purify wastewater of chemical enterprises containing metal ions Cu2+ and Pb2+ up to 29% and dyes in wastewater of textile industries up to 97%, which proves its versatility.
Optimization of the temperature for the production of synthetic wollastonite based on rice husk
Authors:   Kazan National Research Technological University, Gotlib Elena M. , Tverdov Ilya D. ,   Kazan National Research Technological University, Yamaleeva Ekaterina S. ,   Kazan National Research Technological University, Ha Thi Nha Phuong ,   Viet Tri University of Industry
Published: February 2021

Every year around the world, as a result of rice threshing, about 600 million tons of rice husk waste are generated. They pollute the environment, since rice husks do not disintegrate in the ground, due to the presence of silicon dioxide in its composition. Silicon dioxide from rice husk ash differs from other known types of silicon-containing raw materials in that it is in an amorphous state, contains less metal impurities and is chemically more active. At the same time, this amorphous silica can be effectively used in combination with limestone for the synthesis of promising types of fillers for polymer materials, in particular, wollastonite. Based on the results of X-ray analysis, the phase composition of the synthesized filler samples was determined. It was shown that synthetic wollastonite, regardless of the synthesis temperature and the ratio of silicon dioxide and calcium carbonate in its composition, contains mainly β-wollastonite and larnite as impurities. A higher content of β-wollastonite in the composition of the synthesized filler samples is achieved at temperatures of their preparation in the range from 800 to 900 °C. At the same time, in the case of wollastonite with a ratio of silicon dioxide and calcium carbonate 1:1, the synthesis temperature has a greater effect on its composition. Filling epoxy compositions, both natural and synthetic wollastonite, significantly increases their wear resistance. This effect is associated with the anisodiametric shape of the filler particles and is approximately the same when using natural and synthetic wollastonite, with a similar content of β-wollastonite in their composition.
Regularities of changes in the properties of multilayer polymer films depending on their structure
Authors:   Kazan National Research Technological University, Serovа Valentina N. , Muratov Iskander I. ,   Kazan National Research Technological University
Published: February 2021

The physical-mechanical, optical and operational properties of three types of multilayer polymer films that are used in the manufacture of laminates for food packaging and differ in the composition and number of layers (from 3 to 9) are studied: transparent based on high-pressure polyethylene; white (containing a white pigment) on the basis of high pressure polyethylene; transparent barrier based on high-pressure polyethylene, polyamide and ethylene copolymer with vinyl alcohol. For comparison, we also used a single-layer film made of high-pressure polyethylene. The films were tested for tensile strength, resistance to delamination of the welded joint, spectral transmittance, optical density, differential scanning calorimetry curves were registered, and gas permeability was determined. To assess the light aging, the film samples were irradiated with a source of ultraviolet light. The following regularities are revealed: the tensile strength of the studied films does not differ significantly, both when changing their composition and the number of layers; a threefold increase in the number of layers leads to a noticeable increase in the elastic modulus of films made of high-pressure polyethylene with a white pigment; barrier film has a higher modulus of elasticity than transparent films based on high-pressure polyethylene; the resistance to delamination of the welded joint increases in the presence of high-pressure polyethylene films with the same number of layers of white pigment and increasing their thickness; increasing the number of layers leads to a decrease in the spectral transmittance and light resistance of transparent films, but does not affect this indicator of films with white pigment; the role of white pigment as an ultraviolet light absorber causes the greatest light resistance of films and its lesser dependence on the number of layers; barrier film in terms of light transmission and resistance to light aging is inferior to transparent films based on high-pressure polyethylene, but it is significantly superior to a single-layer film; the gas permeability of barrier films naturally decreases with increasing thickness, and after light aging significantly increases due to photo-oxidative degradation of polymer layers and, to a greater extent, the layer of ethylene with vinyl alcohol copolymer.
Prediction of the reactivity of oleum sulfonating agents upon carbamide sulfonation
Authors:   Tambov State Technical University, Degtyarev Andrey A. , Osetrov Alexander Y. ,   Tambov State Technical University, Rostova Daria P. ,   Tambov State Technical University
Published: February 2021

In this work, a research of the reactivity of sulfonating agents of oleum during sulfonation of carbamide was carried out. Cation HSO3+ and sulfur trioxide in monomeric, dimeric, and trimeric forms were chosen as sulfonating agents. The modeling was carried out by the density functional theory (B3LYP5/aug-cc-pVDZ) and the second-order Möller-Plesset perturbation theory (MP2/aug-cc-pVDZ). Simulation was carried out in a vacuum and a polar solvent, which was taken as 100% sulfuric acid. The solvent was taken into account using the COSMO model. The evaluation of the reactivity of sulfonating agents was carried out on the basis of molecular modeling of sulfonating agents and carbamide. The reactivity descriptors were chosen as the reactivity criteria, such as: energies and the location of the highest occupied molecular orbital and lowest unoccupied molecular orbital, charges on atoms, molecular electrostatic potential, absolute hardness and electrophilicity index. It was determined that carbamide is a fairly hard Lewis base, the absolute hardness in vacuum is 6.072, and in a solvent it is 6.635, so charge control is preferable for its sulfonation reaction. Based on this, the greatest preference in the analysis of reactivity indices was given to atomic charges and molecular electrostatic potential. According to the results of the analysis, it was revealed that the highest activity of the studied sulfonating agents is possessed by cation HSO3+, as it has the highest partial charges on atoms (+3.29 in vacuum, +3.38 in a solvent), has the highest electrophilicity (13.45 in a vacuum, 5.35 in a solvent) and does not have steric hindrance factor in contact with the carbamide molecule. Among the forms of sulfur trioxide, preference can be given to both monomeric (highest activity, but there are steric hindrance factor) and trimeric (least steric hindrance factor).
Fluorescent and growth-regulating activity 2-phenylethenylphosphonic acid derivatives
Authors:   I.Ya. Yakovlev Chuvash State Pedagogical  University, Mitrasov Yury N. , Savinova Nadezhda P. ,   I.Ya. Yakovlev Chuvash State Pedagogical  University, Lukicheva Nadezhda A. ,   I.Ya. Yakovlev Chuvash State Pedagogical  University, Smolina Irina N. ,   I.Ya. Yakovlev Chuvash State Pedagogical  University, Kondratyeva Oksana V. ,   Chuvash Republican Institute of  Education Ministry of Education of Chuvashia, Kozlov Vadim A. ,   I.N. Ulyanov Chuvash State University, Vasilieva Tatyana V. ,   I.N. Ulyanov Chuvash State University, Trofimova Larisa M. ,   I.N. Ulyanov Chuvash State University, Shchukina Svetlana M. ,   Cheboksary College of Food Technology and Commerce
Published: February 2021

The paper provides data on an improved method for the synthesis of 2-phenylethenylphosphonic acid dichloride by interacting of carbamide derivatives with 2-phenylethenyltrichlorophosphonium hexachloro-phosphate, which is an intermediate adduct of the reaction of styrene and phosphorus pentachloride. Readily available urea, biuret, and acetylurea have been used as transformers of the adduct. It has been shown that carbamide derivatives are not only donors of the oxygen atom, but they also bind hydrogen chloride released at the stage of complexation into the corresponding hydrochlorides. This allows obtaining the target 2-phenyl-ethenyldichlorophosphonate without admixture of the hydrochlorination by-product. The phenomenon of induced fluorescence of 2-phenylethenylphosphonic acid and its esters in the solid phase and in solution was revealed. The growth-regulating activity of 2-phenylethenylphosphonic acid and O,O-di(p-nitrophenyl)-2-phenylethenyl-phosphonate on the seed germination energy, laboratory and field germinations of grain and vegetable crops was established. It is shown that pre-sowing treatment of the Prokhorovka spring wheat seeds with a 0.0005% aqueous solution of O,O-di(p-nitrophenyl)-2-phenylethenylphosphonate leads to an increase in wheat yield by 21%, which expands the range of products for this purpose. A study of the acute toxicity of 2-phenylethenylphosphonic acid according to LeBlanc on male rats kept on a standard vivarium diet showed that it has a two-phase effect. In the first phase, there are symptoms of damage to the motor part of the peripheral nervous system in the form of local seizures and the central nervous system in the form of the general suppression of motor activity and moderate relaxation of skeletal muscles, and in the second phase, the acid manifests itself in a general toxic effect. Determination of the LD50 of 2-phenylethenylphosphonic acid showed that it belongs to the third class of toxicity – low-hazard substances.
Instability of molecular structure of non-IPR isomer 17984 (C1) of the C76 fullerene and probable ways of its stabilization
Authors:   Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Khamatgalimov Ayrat R. , Kovalenko Valeri I. ,   Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Egorova Anna S. ,   Engeneering Chemical & Technological Institute
Published: February 2021

It is well-known that non-IPR fullerenes are highly unstable. For this reason, they cannot be obtained as pristine fullerenes; however, some of them become stable as derivatives (exohedral or endohedral). In this article, we attempted to elucidate in detail molecular structure for such a non-IPR fullerene. Using theoretical approach supported by DFT calculations, the features of molecular structure of isomer 17894 (C1) of fullerene C76 with data about distribution of single, double and delocalized π-bonds as well its structural formula has been determined for the first time. The instability of the studied fullerene molecule caused by its open-shell structure and significant local overstrains related to the high folding angle value of pentagons in pentalene fragment. The supposed synthesis of the endohedral molecule starts with the ionic pair formation, i.e. anionic fragment of fullerene cage and metal cation electrostatically bound with it. It would lead to closing of open electron shell of fullerene and local overstrain release at pentalene fragment. As to the exohedral derivatives the probable positions of addends are discussed. Both methods in their own demonstrate the possibilities to stabilize the molecule of the C76 isomer 17894. The elucidation and analysis of structural features along with electronic characteristics of non-IPR fullerene molecules appear to be useful for predicting the possibility of their synthesis as derivatives and will assist in determination of their reactivity. This will ensure the targeted production of fullerenes and their derivatives for the needs of medicine, electronics and other industries. The fundamental knowledge of the properties of nanoobjects, namely fullerenes, is actually developing as the independent direction with a long-term perspective.
Reaction of substituted 6-oxocyclohexane- 1,3-dicarboxamides with hydroxylamine
Authors:   Perm State Pharmaceutical Academy, Nosova Natalia V. , Lezhnina Daria D. ,   Perm State Pharmaceutical Academy, Rubtsova Daria D. ,   Perm State Pharmaceutical Academy, Gein Vladimir L. ,   Perm State Pharmaceutical Academy
Published: February 2021

Functionalized cyclohexanones are multifunctional highly reactive available substrates. They are convenient for the synthesis of new compounds, including practically significant ones. The presence of a 1,3-dicarbonyl fragment in their composition makes it possible to obtain various heterocyclic systems in reactions with binucleophilic reagents: indazoles, benzisoxazoles, and diazepines. The interaction of cyclohexanones functionalized with acetyl or alkoxycarbonyl substituents with hydroxylamine was previously studied. It was shown that, depending on the nature of the substituents, the reaction can proceed with the formation of the corresponding oximes, or give products of heterocyclization – benzisoxazoles. The interaction of cyclohexanones containing amide groups in an alicycle with hydroxylamine has not been studied. We studied the reaction of unsubstituted 2-aryl-4-hydroxy-4-methyl-6-oxocyclohexane-1,3-dicarboxamides with hydroxylamine hydrochloride in the presence of an equivalent amount of alkali. When boiling in ethanol in the absence of a catalyst, new 2-aryl-4-hydroxy-6-(hydroxyimino)-4-methylcyclohexane-1,3-dicarboxamides were obtained. Cyclization with the formation of benzisoxazoles does not occur in this case due to a lower positive charge on the carbon atom of the amide group compared to the carbon atom of the acetyl or alkoxycarbonyl groups. The structure of the synthesized compounds was established based on the data of IR, 1H NMR and 13C NMR spectroscopy. The IR spectra of the obtained oximes contain bands of valence vibrations of the OH, NH, and CON groups. The 1H NMR spectra contain four NH-proton singlets of two amide groups, the proton singlet =N-OH group. The 13C NMR spectra of solutions of compounds contain signals of two carbon atoms of amide groups and a carbon atom of the C=N-OH group, which fully confirm the assumed structure.
Indicators of the antioxidant system and oxidative stress of triticale shoots under chloride salinity
Authors:   Tula State Lev Tolstoy Pedagogical University, Ivanishchev Viktor V.
Published: February 2021

Alterations in the activity of antioxidant enzymes (catalase, ascorbate peroxidase, guaiacol peroxidase, glutathione reductase), the content of low molecular weight antioxidants (ascorbic acid, glutathione, and proline), as well as indicators of oxidative stress (hydrogen peroxide, superoxide radical, lipid peroxidation –LPO) in the shoots of triticale (Triticosecale) under short-term (0-96 h) sodium chloride stress (120 mM) were studied with statistical methods: principal component analysis (PCA) and cluster analysis. The application of the PCA method did not always lead to definite results that could be unambiguously interpreted from the point of view of modern concepts in the field of plant physiology and biochemistry. At the same time, high values of the correlation coefficients between individual indicators did not at all reflect their biochemical interdependence. The results obtained allow us to conclude that, under conditions of short-term chloride stress in triticale shoots, the more important function of proline is associated, rather, with the maintenance of osmotic pressure inside the cell than with the role of a low-molecular antioxidant. The mutual positive values of the correlation coefficients (with respect to each other) of the activity of catalase, glutathione reductase, LPO, the content of hydrogen peroxide and superoxide indicate the unidirectionality of the detected alterations, which reflect their known biochemical relationship and the need for glutathione reductase to maintain a certain redox-state in plant cells. With cluster analysis it was shown that under conditions of short-term chloride stress in triticale shoots, the studied enzymes (catalase, ascorbate peroxidase, guaiacol peroxidase, and glutathione reductase) play a more significant role in neutralizing of reactive oxygen species, and maintaining the state of membranes, than low molecular weight antioxidants.
API-monitoring of synthetic pyrethroids by gas chromatography with mass spectrometric detection
Authors:   Federal Center for Toxicological, Radiation and Biological Safety, Mukharlyamova Aisylu Z. , Fitsev Igor M. ,   Federal Center for Toxicological, Radiation and Biological Safety, Rakhmetova Elvira R. ,   Federal Center for Toxicological, Radiation and Biological Safety, Mukhammetshina Aygul G. ,   Federal Center for Toxicological, Radiation and Biological Safety, Makaeva Alsy R. ,   Federal Center for Toxicological, Radiation and Biological Safety, Shlyamina Oksana V. ,   Federal Center for Toxicological, Radiation and Biological Safety, Nasybullina Zhanna R. ,   Federal Center for Toxicological, Radiation and Biological Safety
Published: February 2021

The article presents the results of API (Latin Ápis – bee) monitoring the content of residual amounts of synthetic pyrethroids in honey bees using gas chromatography with mass spectrometric detection (GC-MS). The pesticides discussed in this article were selected based on the results of API monitoring of honey bees using GC / MS. The proposed GC-MS method for monitoring synthetic pyrethroids makes it possible not only to identify the causes of lethal intoxication of bees, but also to prevent the possible consequences of synthetic pyrethroids getting into beekeeping products and, consequently, their distribution along trophic routes. The latter has a direct impact on the quality of human life safety. It has been shown that for the detection by GC-MS of synthetic pyrethroids contained in a bee matrix, an important role is played by correctly selected conditions for sample preparation and purification of the extract, which contribute to the isolation of the target compounds from a complex matrix, which are present in it, often at the level of the minimum permissible level (MDU). In this work, sample preparation was carried out by solid-phase extraction (SPE) on a chromatographic column using a C18 sorbent with grafted octadecyl groups. A GC-MS multimethod has been developed for the determination of synthetic pyrethroids (prometrine, bifenthrin, β-cyagalotrin, isomers of permethrin and cypermethrin, fenvalerate, deltamethrin, which, along with other insecticides, for example, neonicotinoids, are frequent causes of lethal intoxication of bees. Quantitative determination of synthetic pyrethroids under GC-MS conditions is carried out in the registration mode of selective ions (main and confirmatory ions, respectively). The proposed method for the determination of synthetic pyrethroids for the purposes of their API monitoring is characterized by a detection limit that does not exceed the MRL in ecomonitoring objects.
Determination of glyphosate in honey by high-performance liquid chromatography
Authors:   Federal Center for Toxicological, Radiation and Biological Safety, Burkin Konstantin Ye. , Zhilkin Mikhail Ye. ,   Federal Center for Toxicological, Radiation and Biological Safety, Likhacheva Alena Yu. ,   Federal Center for Toxicological, Radiation and Biological Safety, Balymova Maria V. ,   Federal Center for Toxicological, Radiation and Biological Safety, Rakhmetova Elvira R. ,   Federal Center for Toxicological, Radiation and Biological Safety, Mukhammetshina Aigul G. ,   Federal Center for Toxicological, Radiation and Biological Safety, Fitsev Igor M. ,   Federal Center for Toxicological, Radiation and Biological Safety
Published: February 2021

The article presents the results of the developed highly sensitive and easily implemented method of sample preparation and determination of the content of residual amounts of glyphosate – one of the most widely used non-selective herbicides of systemic action for the destruction of weeds, in flower honey samples by high-performance liquid chromatography (HPLC) with a fluorescent detector (FD) in the framework of ensuring the safety of beekeeping products. The HPLC stage with FD was preceded by sample preparation, which included the following steps: extraction of glyphosate from an artificially contaminated honey sample with a mixture of water/methanol (1:1) with subsequent addition of a four-fold excess of acetonitrile to the resulting solution to separate a complex multicomponent matrix of honey by centrifugation; filtration of the supernatant and evaporation of the filtrate on a rotary evaporator; dissolution of the resulting residue in a borate buffer solution in order to achieve an alkaline pH value of the medium equal to 8.5-9.5; pre-column derivatization of glyphosate in an alkaline medium with an acetonitrile solution of FMOC-Cl for 30 minutes to obtain a fluorescent herbicide derivative – N-alpha-(9-fluorenylmethyloxycarbonyl)-N-alpha-(phosphonomethyl)-glycine; adding at the end of the derivatization process to the reaction mixture of formic acid in order to transition from alkaline to acidic conditions and stabilize the glyphosate derivative; adding dichloromethane to remove the unreacted excess of the derivatizing agent. Subsequent chromatographic analysis of the fluorescent derivative glyphosate was performed on a reverse-phase packed column "Luna 100 C18-2.5 µ", characterized by versatility and stability in the range of pH values from 1.5 to 11.0, in the isocratic elution mode of mobile phase composition acetonitrile/an aqueous buffer solution of potassium phosphoric acid with a pH value equal to 4.5-5.5 (30:70). The developed method was successfully tested on real samples of flower honey.
Thermodynamic and experimental simulation of interactions in the Ta-ZnS system
Authors:   Ural Branch of the Russian  Academy of Sciences, Udoeva Lyudmila Yu. , Agafonov Sergey N. ,   Ural Branch of the Russian  Academy of Sciences, Petrova Sofia A. ,   Ural Branch of the Russian  Academy of Sciences
Published: February 2021

The article presents the results of studies to estimation the possibility of sulfiding of metallic tantalum by zinc sulfide in an inert atmosphere. To theoretically substantiate the possibility of the process, the HSC 6.12 Chemistry software package (Outotec) was used, which allows predicting the equilibrium composition of the interaction products. The Gibbs energies of possible reactions in the ZnS-Ta system are calculated, the optimum operating parameters of the process of complete transformation of metallic tantalum into TaS2 are determined. Experimental studies were carried out in a tubular furnace in a flow of an inert gas (helium) supplied through a closed loop of an alundum reactor. Components with different molar ratios compressed into tablets were kept at the temperature 1300 ° C for 90 minutes. It has been found tantalum disulfide of two modifications (hexagonal and trigonal systems) and Ta5S8 (14.1%) are formed at a stoichiometric ZnS / Ta molar ratio of 2.0. Its subsulfides (Ta1.23S2, Ta3.1S6, TaS (y)), which are intermediate phases in the transformation of tantalum-to-TaS2, are formed if a sulfidizer is deficient. The identification of the phases and the estimation of their proportion in the sulfiding product were made by the full-profile analysis by Rietveld method. The experimental conditions did not reveal the formation of complex sulfides like the ZnxTaS2, the formation of which is possible because of zinc intercalation between the layers of the tantalum disulfide basic structure of the crystal lattice.
Synthesis of sulfonamide derivatives containing the structural fragment of pyrazol-1-yl-pyridazine
Authors:   Yaroslavl State  Pedagogical University Named after K.D. Ushinsky, Komshina Ljudmila A. , Маrtazova Valentina V. ,   Yaroslavl State  Pedagogical University Named after K.D. Ushinsky, Korsakov Mikhail K. ,   Yaroslavl State  Pedagogical University Named after K.D. Ushinsky, Proskurina Irina K. ,   Yaroslavl State  Pedagogical University Named after K.D. Ushinsky, Коtov Аlexandr D. ,   Yaroslavl State  Pedagogical University Named after K.D. Ushinsky, Karavaeva Еlena B. ,   Russian State University Named after A.N. Kosygina (Technologies. Design. Art)
Published: February 2021

Sulfonamide derivatives of heterocyclic compounds are promising targets for the search for new substances with specific biological activity. They are widely used as inhibitors of human carbonic anhydrases involved in the implementation of various biochemical processes. The presence of several heterocyclic systems in the structure of sulfonamides significantly increases the ability to bind to active sites of carbonic anhydrases and inhibit their activity. Therefore, the development of approaches to the preparation of sulfonamides of polynuclear heterocyclic compounds is of great scientific interest. This article proposes a multistage scheme for the synthesis and characterization of new sulfonamide derivatives of 1-aryl-6-pyrazol-1-yl-pyridazines. The synthesis of substituted pyrazol-1-yl-pyridazines was carried out by sequential conversion of arylpyridazinones by refluxing in phosphorus oxychloride to 3-chloro-6-arylpyridazines, at the next stage as a result of the nucleophilic substitution of activated chlorine in the pyridazine ring with hydrazine, arylpyridazines were obtained with the reaction Refluxing in butanol, the target compounds with a 3,5-dimethylpyrazole structural fragment were synthesized. The study of the regularities of the course of sulfonylchlorination of 1-aryl-6-pyrazole-1yl-pyridazines made it possible to establish the effect of the substrate structure on the direction of the process and the selectivity of the reaction, as well as on the possibility of the formation of disubstitution products. The corresponding disulfonyl chloride was obtained only in the case of sulfonylchlorination of 1-(4-methoxyphenylpyridazin-3-yl)-3,5-dimethyl-1H-pyrazole at 100 °С for 10 h. In this case, the hydrogen atoms in position 3 of the benzene ring and position 4 of the pyrazole ring. In all other cases, monosubstitution products were obtained at the 4-position of the pyrazole ring. This is evidenced by the data of 1H NMR spectroscopy. On the basis of the obtained sulfonyl chlorides, the corresponding mono- and disulfonamides were synthesized. Convincing proof of the structure of all the obtained compounds has been carried out by a combination of mass spectrometry and NMR spectroscopy data.
Synthesis and properties of 1-aminocarbonylmethyl-5-aryl- 4-aroyl-3-hydroxy-3-pyrroline-2-ones
Authors:   Perm State Academy of Pharmacy, Gein Vladimir L. , Pastukhova Evgenia V. ,   Perm State Academy of Pharmacy
Published: February 2021

3-Hydroxy-3-pyrrolin-2-ones are fully hydrogenated heterocyclic compounds, the base of which is included in a number of biologically active substances and drugs. Scientists' interest in 3-Hydroxy-3-pyrrolin-2-ones is due to the fact that, with their availability and high stability, they also have high reactivity due to the active carbonyl group in the third position of the heterocycle and easily interact with moconucleophiles. In addition, the presence of acyl and ethoxycarbonyl groups in the fourth position of the heterocycle makes it possible to obtain various condensed systems in reactions with binucleophiles, thereby making it possible to expand the range of the indicated compounds. We set the task to prepare 5-aryl-4-acyl-3-hydroxy-3-pyrrolin-2-ones containing an amino-carbonylmethyl substituent in the first position of the heterocycle, which were not previously described in the literature. It was also supposed to establish how the obtained compounds react with hydrazine hydrate. A series of 1-aminocarbonylmethyl-5-aryl-4-aroyl-3-hydroxy-3-pyrrolin-2-ones was obtained by setting up a three-component reaction of aroylpyruvic acid methyl ester with aromatic aldehydes and glycinamide hydrochloride in glacial acetic acid. The structure of the obtained compounds was established on the basis of IR and 1H NMR spectroscopy data. Based on the data of 1H NMR spectroscopy and a positive reaction with an alcoholic solution of iron(III) chloride, the predominant existence of the obtained compounds in the enol form was established. The article describes the mechanism of three-component reactions, the structural formulas of the obtained compounds, their physicochemical properties and spectral characteristics, as well as the yields of the reaction products. We have also studied the interaction of 1-substituted 5-aryl-4-acyl-3-hydroxy-3-pyrrolin- 2-ones with such a binucleophilic reagent as hydrazine hydrate. As a result of refluxing 1-amino-carbonylmethyl-3-hydroxy-4-(4-methoxybenzoyl)-5-(2-chlorophenyl)-3-pyrrolin-2-one and hydrazine hydrate in glacial acetic acid, 2-[4-(2-chlorophenyl)-3-(4-methoxyphenyl)-6-oxo-4,6-dihydropyrrolo [3,4-c] pyrazol-5(1H)-yl] acetamide. The article describes the proposed reaction mechanism, product yield, its physicochemical properties and spectral characteristics.
Classifying High-cadence Microlensing Light Curves. I. Defining Features
Authors: Khakpash Somayeh , Pepper Joshua , Penny Matthew , Gaudi B. Scott , Street R. A.
Published: February 2021

Microlensing is a powerful tool for discovering cold exoplanets, and the Roman Space Telescope microlensing survey will discover over 1000 such planets. Rapid, automated classification of Roman’s microlensing events can be used to prioritize follow-up observations of the most interesting events. Machine learning is now often used for classification problems in astronomy, but the success of such algorithms can rely on the definition of appropriate features that capture essential elements of the observations that can map to parameters of interest. In this paper, we introduce tools that we have developed to capture features in simulated Roman light curves of different types of microlensing events, and we evaluate their effectiveness in classifying microlensing light curves. These features are quantified as parameters that can be used to decide the likelihood that a given light curve is due to a specific type of microlensing event. This method leaves us with a list of parameters that describe features like the smoothness of the peak, symmetry, the number of peaks, and the width and height of small deviations from the main peak. This will allow us to quickly analyze a set of microlensing light curves and later use the resulting parameters as input to machine learning algorithms to classify the events.