Department Of Chemistry Research Articles

Peer Review Statement

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.• Type of peer review: Double Anonymous• Conference submission management system: Morressier• Number of submissions received: 167• Number of submissions sent for review: 126• Number of submissions accepted: 113• Acceptance Rate (Submissions Accepted / Submissions Received × 100): 67.7• Average number of reviews per paper: 1.63• Total number of reviewers involved: 38• Contact person for queries: Name: Robby Gus Mahardika Email: robby@ubb.ac.id Affiliation: Department of Chemistry, Universitas Bangka Belitung

Effect of Integrated Nutrient Management on Yield, Uptake and Soil Properties of Pearl Millet (Pennisetum glaucum L.) in Alluvial Soil of Gird Region of Madhya Pradesh

Aims: Effect of Integrated nutrient management onyield, uptake and soil properties of pearl millet (Pennisetum glaucum L.) in alluvial soil of Gird region of Madhya Pradesh.
 Study Design: Randomized block design.
 Place and Duration of Study: Department of Soil Science and Agricultural Chemistry, R.V.S.K.V.V., CoA, Gwalior, Districts of Madhya Pradesh during kharif, 2022.
 Methodology: There were 12 treatments T1 – Control, T2 -50% NPK, T3-75% NPK, T4 -100% NPK, T5 - 150% NPK, T6 -100% NPK-S, T7 -100% NPK ZnSO4, T8 -100% NPK + FeSO4, T9 -50% NPK + FYM, T10 -75% NPK + FYM, T11 -100% NPK + FYM and T12-100% NPK + FYM + {PSB+ Azotobacter (Seed treatment)} and were replicated thrice under RBD and were statistically analyzed by the Fishher the analysis of variance technique was adopted as suggested by Panse and Sukhatme (1984) for Randomized Block Design. The pH , EC, OC, N, P, K and S content before creation of treatments were 7.72, 0.23 dSm-1, 0.39 %, 170 kgha-1, 12.04 kg ha-1 and 180 kg ha-1 respectively.
 Results: The results indicated that yield, uptake of nutrients and soil properties pH, EC, OC, Available Nitrogen, Phosphorus, Potassium and Sulphur were found highest in the treatment T12-100% NPK + FYM + {PSB+ Azotobacter (Seed treatment)} and was found lowest in the treatment T1 – Control.
 Conclusion: Based on experimental findings it can be concluded that application of100% NPK + FYM + {PSB+ Azotobacter (Seed treatment)} is beneficial in terms of yield, uptake of nutrients and Soil chemical properties pearl millet.

Assessment of Physicochemical Parameters of Drinking Water in the Schools of Bagnashkali, Palpa, Nepal

This study aims to assess the physicochemical parameters of drinking water in schools in the Bagnashkali Rural Municipality in Nepal according to standard methods. Physicochemical analysis was performed at the Department of Chemistry at Tribhuvan Multiple Campus, Palpa, in March 2022 using samples collected randomly from different schools. The study found that water samples from schools in Bagnashkali meet NDWQS and WHO guidelines as pH (7.28- 7.98), hardness(60-140 mg/L), conductivity (65.3-173.2 µs/cm), alkalinity (46-96.6 mg/L), chloride (0.3-0.7 mg/L), dissolved oxygen (9.12-12.6 mg/L), total dissolved solids (9.12-12.6 mg/L), free CO2 (7.04-10.56 mg/L) and iron (0.017-0.068 mg/L) which were all except for temperature within acceptable limits. The temperature of the water samples in this study ranged from 21°C to 28°C. The study found that the water quality in the selected schools was good and met the acceptable standards in terms of physicochemical parameters.

Guest Editor’s Note

The process of writing review articles originally materialized as a component of the student evaluation process during the final year of their research projects, coinciding with the closure of universities due to the COVID-19 pandemic. In these challenging times, final-year honors degree students dedicated themselves to extensive literature research from their homes. As the evaluation phase concluded, it became evident to the Chemistry department that several of the review articles had reached a remarkable level of quality, making them suitable for publication in a reputable scientific journal.
 Thus, the idea emerged to compile and publish these outstanding articles in a special edition of our esteemed journal, Current Scientia, formerly known as the Vidyodaya Journal of Science. This endeavor involved meticulous scrutiny and enhancement of both the content and coverage of the articles, a collaborative effort between the students and their dedicated supervisors. The contributions of the supervisors were invaluable in this process.
 Reflecting upon the circumstances, one might consider the period of house arrest during the pandemic as a blessing in disguise. It provided an opportunity for students and supervisors to invest more time and effort into refining their work. The synergy that emerged between them during this challenging time is truly commendable.
 With the publication of this special issue, we hope that it will set a new precedent and ignite the academic curiosity of scholars from various departments within the faculty. We aspire to encourage academics to craft their own high-quality review articles in their respective fields for potential publication in this journal in the future, fostering a culture of scholarly contribution and collaboration.
 Dr. Mahesh KarunarathneGuest EditorSpecial Issue Current Scientia (formerly Vidyodaya Journal of Science Special Issue)

Improvement of Acid-Base Materials Understanding SMAI Gumukmas Students with Simple Practicum

SMAI Gumukmas is a privately-funded high school situated in Purwoasri Village, Gumukmas District, Jember, with a B accreditation status. The absence of laboratory resources challenges devising inventive, uncomplicated, and pragmatic classroom learning, such as Chemistry. Collaboration between SMAI Gumukmas and the Chemistry Department lecturers to conduct community service is a mutually beneficial initiative that fosters curriculum innovation and practicum subjects. Acid-base is a chemistry topic with material relevant to all grade levels and can be easily visualized through practical examples from everyday life. The methodology involves delivering a lecture or theoretical framework on acid-base, followed by practical work. The acid-base practical is designed to commence with comprehension of the acid-base concept, including everyday life examples, before progressing to classroom implementation. The acid-base theme learning activities and practicum at SMAI Gumukmas proceeded seamlessly and successfully. The initial class consisted of 40 students from grades 11 and 12, while the subsequent consisted of 33 grade 10 students. The students exhibited a positive response as their studies progressed with exemplifications derived from everyday life.

Pharmacokinetics of a New Dimethylamineethanol Derivative Administered Orally to Laboratory Animals

A new derivative of dimethylaminoethanol, butanedioic and trans-butenedioic acids (laboratory code ADK-17) was synthesized at the Organic Chemistry Department of the Saint Petersburg State Chemical and Pharmaceutical University (SPSPU). This promising nootropic and anti-asthmatic agent is planned for use in an oral dosage form. The aim was to calculate the pharmacokinetic parameters of the synthesized compound and to determine its possible biotransformation pathways. Rabbits of the Soviet Chinchilla breed were used as a test system in the preclinical study of the compound pharmacokinetics. In accordance with the designed schedule, blood was taken from the marginal vein of the ear, and urine samples were taken. Quantitative determination in biological media was carried out using an Ultimate 3000 liquid chromatograph with a Q-Exactive mass-selective detector with electrospray ionization in accordance with OFS 1.2.1.100015 (Chromatography) of the State Pharmacopoeia by ultra-performance liquid chromatography–mass spectrometry (UPLC-MS). To study the pharmacokinetics of the ADK-17 preparation, a measurement procedure was developed with a detection limit in biological media ranging from 10-6 to 10-3 mg/ml. The determined harmacokinetic parameters show that the absorption of ADK-17 into the systemic circulation from the gastrointestinal tract occurs at an average rate, with its maximum concentration in blood plasma during the oral route of administration being observed between 60–90 min. The elimination half-life from the systemic circulation comprises 4.3 h. Urinary excretion in the first 4 h proceeds at a high rate; however, the compound is detected in the urine within 3 days and in the blood within 2 days from the moment of administration.

CONFORMATIONAL STUDY OF MOLECULES IN A BIOLOGICAL ENVIRONMENT, DESIGN OF INHIBITORS OF HUMAN AMINOPEPTIDASE M1 IMPLICATED IN CANCER THERAPY

Objective: A novel subnanomolar anticancer hydroxamic acid containing drug candidates, inhibitors of human M1 aminopeptidase (APN) a recent validated target and has reached the predicted subnanomolar range of inhibitory potency. Methods: A quantitative structure activity relationships (QSAR) complexation model has been developed from a compounds of 37 hydroxamic acid derivatives (AHD1-37 as training set, TS) to establish a linear correlation between the calculated relative Gibbs free energies (GFE: ΔΔGcom) of APN-AHDx complex formation and the experimental inhibition potency (Kiexp). The predictive power of the QSAR model was then validated first with 9 other AHDs not included in the TS and thereafter with the generation of a 3D-QSAR-PH4 pharmacophore (PH4) model to screen the AHD chemical subspace built as a virtual combinatorial library of more than 58,644 AHD analogs). Finally the best PH4 hits were evaluated with the initial QSAR model for predicted potency (Kipre) and pharmacokinetic profile. Results: The QSAR model linear correlation equation: pKiexp=-0.1901×∆∆Gcom + 8.2886 , R2=0.94, the subsequent PH4 model linear correlation between experiment and PH4-estimated Ki: pKiexp=1.0006× pKipre + 0.0028, R2=0.79 documents the high predictive power of this approach. Finally the screening of the virtual library of AHD analogs yielded 95 orally bioavailable candidates the best reaching a predicted potency (Kipre) of 50 pM and displaying favorable pharmacokinetic profile. Conclusion: The combined use of molecular modeling (QSAR) and in silico PH4-based screening of the hypothetical combinatorial library has resulted in proposed and predicted potent anticancer candidates with a suitable pharmacokinetic profile. Peer Review History: Received: 3 August 2023; Revised: 12 September; Accepted: 25 October, Available online: 15 November 2023 Academic Editor: Dr. Nuray Arı, Ankara University, Turkiye, ari@ankara.edu.tr Received file: Reviewer's Comments: Average Peer review marks at initial stage: 7.0/10 Average Peer review marks at publication stage: 9.0/10 Reviewers: Prof. Hassan A.H. Al-Shamahy, Sana'a University, Yemen, shmahe@yemen.net.ye Prof. Dr. A. Hakan AKTAŞ, Süleyman Demirel University, Faculty of Science and Art, Department of Chemistry, Isparta-Turkey, hakanaktas@sdu.edu.tr

Impact of Long-term Use of Fertilizers and Manure on Distribution of Soil-inorganic Phosphorus Fractions in a Vertisol

The field experiment was conducted during the kharif season under the AICRP on Long-Term Fertilizer Experiment at the Research Farm, Department of Soil Science and Agricultural Chemistry, JNKVV, Jabalpur (M.P.), India. The investigation was carried out to assess the distribution of P fractions in Vertisol after the harvesting of the soybean crop. Eight treatments were imposed with four replications in a simple randomized block design. The treatments were applied in combination with different doses of fertilizer viz., T1 (50% NPK), T2 (100% NPK), T3 (150% NPK), T4 (100% N), T5 (100% NP), T6 (100% NPK+FYM), T7 (100% NPK-S), and T8 (control). Through the findings, the soil pH and electrical conductivity (dS m-1) did not show significant changes even after the long-term application of various fertilizer levels compared to their initial values. The treatment with 100% NPK + FYM exhibited the highest organic carbon (g kg-1) content and available N, P, and K (kg ha-1) content over the control. The various forms of phosphorus in the soil were observed in the following order: Ca-P > Fe-P > Al-P > Occluded-P > Saloid-P . The Ca-P content was highest when 100% NPK fertilizer and farmyard manure (FYM) were used together. The analysis showed that the presence of saloid-P significantly influences the availability of phosphorus in Vertisol soil. Based on the current investigation, it is recommended to use integrated nutrient management, which includes both 100% NPK fertilizer and FYM, to prevent phosphorus deficiency in soybean cultivation in Vertisol.

End-to-end Standardization of Original Medicines when Determining Related Impurities

Introduction. For tablets “Malоben, 60 mg” and “Etmaben, 300 mg”, permission was received to conduct phase I clinical trials, so they required a full cycle of research and standardization.Aim. Development of a unified analytical procedure for the determination of related impurities in samples (RS, API, FPP) of Malоben and Ethmaben.Materials and methods. RSs were obtained at the Department of Organic Chemistry of the St. Petersburg State Chemical and Pharmaceutical University; the synthesis of APIs and the production of FPP were carried out on an industrial scale in pharmaceutical production. The studies were carried out on a Flexar liquid chromatograph (PerkinElmer, USA), equipped with a pump (formation of a gradient on the low-pressure side), an autosampler, a column thermostat, a UV detector and a chromatographic column Intersil® ODS-3V, 5 µm, 100 Å, 250 × 4, 6 (Phenomenex, Japan).Results and discussion. In the research, uniform optimal chromatographic conditions were selected using the HPLC method to determine the RP in RS, API and FPP of Maloben and Ethmaben. Column C18 250×4.6 mm, mobile phase 0.1% phosphoric acid and acetonitrile (gradient elution), flow rate 1 ml/min, sample volume 10 µl, UV detector (270 nm). They were validated in terms of specificity, linearity, detection limit, precision, robustness, and solution stability. Analytical concentration levels were selected for the formation of draft regulatory documents. Using the developed analytical technique, samples of RS, API and tablets of malоben and ethmaben were analyzed.Conclusion. A full cycle of research was carried out, an analytical methodology was developed and related impurities were identified in RS, API and FPP of Maloben and Ethmaben.

Reaction Engineering and Comparison of Electroenzymatic and Enzymatic ATP Regeneration Systems

AbstractInvited for this issue's Front Cover are the group of Bioprocess Engineering at TU Dortmund University, Department of Chemistry at Johannes Gutenberg University Mainz, and the Biotechnology Group at Constructor University. The front cover illustrates the electroenzymatic regeneration of ATP. The electrons of an enzymatically catalyzed redox reaction necessary for the ATP regeneration cascade are transferred to an electrode mediated by ferrocenyl‐methanol. Regenerative and green energy can therefore be used to drive the reaction. Cover design by Tobias Prenzel and Finn Moeller. Read the full text of the Research Article at 10.1002/celc.202300332.

Abstract 16919: Analysis of Astrocyte Activation and Reduction of Motor Deficits Following hSOX2 Gene Therapy Delivered Using PAMAM Dendrimer Nanomolecules in Ischemic Stroke

PAMAM dendrimers are 3-dimensional nanomolecules which have the capability to deliverbiomolecules and gene therapy to the cells in vitro and in vivo . We have previously used the generation-4 surface-modified PAMAM dendrimers having 90% hydroxyl groups and 10% amine groups (G4-90/10) which are safe, cross the blood-brain barrier and deliver the biomolecules into the cells. In thecurrent study, we utilized G4-90/10 PAMAM dendrimers to deliver a gene therapy to the infarct in aischemic stroke brain in rats. Following an ischemic stroke, glial cells (such as astrocytes) are recruitedat the infarct region to perform maintenance functions, creating severe neuroinflammation. The goalof this study was to reprogram some of the astrocytes into neuronal lineage and repopulate the infarctregion. In addition, we also analyzed the temporal profile of astrocyte activation following ischemicstroke in the striatal and cortical regions to determine the time-point at which the maximum gliosisoccurs. This gives us a crucial timeline for treatment intervention to achieve astrocytereprogramming. We have used a transcription factor (hSOX2 gene), which was then delivered to thestroke brain in rats using the G4-90/10 dendrimers. Our results showed that the maximum glial cellactivation occurs in striatal and cortical regions on day 4 following ischemic stroke. Following genetherapy intervention, our initial analyses indicated that there was recovery from behavioral deficits inthe stroked rats compared to the vehicle-treated stroked rats and sham controls. Overall, these resultsshow that PAMAM dendrimers have significant potential delivering therapeutic molecules for treatingstroke and other neurological conditions. Support for this study was provided by the American Heart Association (18AIREA 33990094),Neuroscience program, the College of Medicine, department of Chemistry and Biochemistry, the JohnG. Kulhavi Professorship and the E. Malcolm Field and Gary Leo Dunbar Endowed Chair of Neuroscience at Central Michigan University.

Effect of Bulking Agents on Physical, Chemical and Biological Properties of Latex Sludge Waste

Aim: Production of latex sludge waste biocompost by co composting with different bulking agents like sawdust, zeolite and cattle manure in various ratios and checking its feasibility in agriculture use.
 Study Design: The experiment was conducted by completely randomized design with ten treatments and three replications
 Place and Duration of Study: The experiment was conducted at the Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani, Kerala Agriculture University between November 2022- February 2022
 Methods: The latex sludge waste collected from HLL, Trivandrum was used for the study. The latex sludge waste is mixed with different bulking agent like sawdust, zeolite and cattle manure in different ratios. Composting inoculum is used equally in all the treatments to fasten the composting process. The resultant composts were analysed for physical, chemical and biological properties. 
 Results: The compost prepared from latex sludge, zeolite, sawdust and cattle manure resulted higher values of major macro and micro nutrients and good physical properties compared to other treatments. A gradual decrease in C:N ratio and carbon dioxide emission was observed for a period of 120 days of composting in all the experiment. The results showed that the co-composting of latex sludge with sawdust, zeolite and cattle manure produces quality compost. All the ratios of the mixture of composts were found to be a better growth medium for crops compared to application of latex sludge alone
 Conclusion: Composting of latex sludge is found to be one of the economic and environmentally viable option for the management of large quantity of latex sludge waste. The compost showed optimum physical, chemical and biological properties and can be utilize for crop production.

Development of a method of quantitative determination of the active substance in Angiolin eye drops by the method of high-performance liquid chromatography

One of the most common eye diseases is a burn injury. Hence, one of the pressing challenges in the field of pharmacy today is the development of new ophthalmic medications, specifically eye drops. Researchers from the Department of Pharmaceutical, Organic, and Bioorganic Chemistry at Zaporizhzhia State Medical and Pharmaceutical University, led by Professor I. A. Mazur, have successfully synthesized a novel compound. This compound is a derivative of 1,2,4-triazole, specifically (S)-2,6-diaminohexanoic acid 3-methyl-1,2,4-triazolyl-5-thioacetate. Notably, this compound demonstrates anti-inflammatory, wound-healing, and reparative activities. The aim of the work is to develop a method of quantitative determination of the active substance in Angiolin eye drops by the method of high-performance liquid chromatography. Materials and methods. The research employed a liquid chromatograph equipped with a UV detector. A column Hypersil ODS C-18 measuring 250 by 4.6 millimeters with a particle size of 5 microns was used. Results. It was determined that the angiolin content in the 1 % eye drops in series 1 falls within the range of 0.985 to 1.010 grams. This indicates that, in terms of the active substance content, the studied series complies with the requirements of the State Pharmacopoeia of Ukraine. Conclusions. As a result of the conducted research, a method for quantitatively determining the active substance in Angiolin eye drops using high-performance liquid chromatography was developed.

Antimicrobial Activities of Some Constituents Isolated from a Kenyan Medicinal Plant, Capparis fascicularis DC

Background of the Study. Capparis fascicularis DC. is an indigenous medicinal plant belonging to the family Capparaceae found in Nyandarua County, Nairobi, Kenya, and many parts of Africa. It is a shrub whose roots are used traditionally to treat colds. Aim. The aim of the present study is to carry out antimicrobial activities of solvent extracts of different parts of Capparis fascicularis, characterize the phytochemical constituents of the most active extract, and identify the most active compounds. Place and Duration of the Study. All the experiments were carried out in the departments of Chemistry and Microbiology, Kenyatta University, Nairobi, Kenya. Methodology. Petroleum ether, ethyl acetate, methanol, and water extracts from the leaves, stem bark, and root bark of C. fascicularis were screened against selected strains of both Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Salmonella typhimurium and Escherichia coli) bacteria using disc diffusion and tube dilution methods. Fractionation of the most active crude extract was carried out by column chromatography, and the fractions together with the most active crude extract were screened against the selected bacterial strains. The most active fraction was further fractionated, and the subfractions were screened against the bacterial strains to test for possible synergistic effects between the subfractions and their constituents. The most active fraction was then analysed by GC-MS and LC-ESI-MS methods to identify the major constituents. Results. The ethyl acetate extract of C. fascicularis root bark (CFR2) showed a significant in vitro antibacterial activity. From the seven fractions of CFR2 obtained, fraction 2 (F2) had the lowest MIC value and was thus most active. Moreover, F2 was found to be more active compared to the four subfractions obtained from it. This suggested that constituents of F2 worked in synergy. Fraction 2 contained phenols, terpenes, and flavonoids. Two compounds were identified by GC-MS as 2,4-di-tert-butylphenol and (E,E)-2,4-decadienal, while three compounds were identified by LC-ESI-MS as tanshinone II A, cryptotanshinone, and danshensu. Conclusion. The study revealed that CFR2 is the most active extract on bacteria, suggesting that most antimicrobial compounds are concentrated in the roots of C. fascicularis. A follow-up study is directed towards chromatographic separations to obtain the other chemical constituents and screen them against various strains of bacteria.

Influence of Pseudomonas and Biofertisol as Foliar Spray on Nodulation Attributes and Yield of Vegetable Pea under STCR Approach

A field experiment was carried out during the rabi season in the Experimental Field, Department of Soil Science and Agricultural Chemistry, JNKVV, Jabalpur (M.P.) under RBD design with four replications consisting of five treatments of two types of biofertilizers: Pseudomonas and Biofertisol, and scheduled combinations of inorganic fertilizers based on STCR (Soil Test Crop Response) to achieve the desired yield using the vegetable pea variety PSM-3. The response due to treatment of T4 (TY 100 q (58:110:47) + 5 t FYM+1 spray of Pseudomonas+1 spray of Biofertisol) was significantly effective in increasing nodulation attributes (nodulation enumeration, biomass and leghaemoglobin content) by 28.46, 47.15, and 35.29%; 78.33, 95.86, and 86.17%; and 21.70, 65.70, and 20.26%, respectively, relative to that of control. Yields of the crop were best harvested due to T4 by 85.97 % over that of control 56.70 kg ha-1. The continuous application of chemical fertilisers has decreased the fertility of the soil and degraded the soil. The reduction in the fertility of the soil has resulted in poor crop yields. The nutrient management of all the treatments involves the judicious use of organic and inorganic fertilizers, along with microbes, to meet the nutrient needs of the crop while minimizing environmental impacts.

Optimizing the Implementation of Computer-Based Exams to Paperless in the Department of Chemistry of Musamus University

This research is a descriptive study that aims to optimize the implementation of computer-based exams in minimizing the use of paper in the Department of Chemistry of Musamus University. The subject of this research is the fifth semester students of the Chemistry Education Department in the Classroom Action Research Course. The research data was obtained through a student response questionnaire with the implementation of a computer-based exam filled in via the Google form. From the results of descriptive data analysis it was obtained that the response of students to the implementation of computer-based exams was positive with an average value of student responses of 83.08%. The conclusion that can be obtained from this research is that the computer-based test with the wondershare quiz creator software can minimize the use of paper. In addition, computer-based exams can make students independent in working on problems, as well as accelerated acceptance of student exam results.

The research experiences for undergraduates (REU) program

The research experiences for undergraduates (REU) program Greg M. Swain, hailing from the Department of Chemistry at Michigan State University, examines cross-disciplinary training in sustainable chemistry and chemical processes, including the critical role of mentoring and finding research experiences for undergraduates. Sustainability is the practice of reducing the environmental impacts of human existence and conserving natural resources for future generations. Green chemistry is a part of the sustainability approach that encourages manufacturing processes and the design of products that minimize the use and generation of hazardous substances. Stated another way, sustainable chemistry and chemical processes should use resources, including energy and raw materials, “at a rate at which they can be replaced naturally, and the generation” of waste cannot be faster than the rate of their remediation, as Horváth IT points out. (1)

Optimization of the Pedagogical Process in Teaching Chemistry to First-Year Students of the Ural State Medical University

The purpose of research is to determine directions for optimizing the educational process with the introduction of new methodological approaches. For this purpose, the paper set the tasks to analyze the current methodological aspects of the component of the pedagogical process of teaching chemistry to first-year students of the medical and preventive faculty of the Ural State Medical University (USMU, Yekaterinburg); asess the impact of new methodological approaches in teaching on the performance of students. The discipline “Chemistry” is studied in the first semester, classroom hours for the discipline include lectures (32 hours), practical exercises and laboratory work (34 hours), which are conducted at the department of general chemistry of USMU.Materials and methods. The methodology for teaching chemistry to first-year students of the medical and preventive faculty of USMU (Ekaterinburg) is analyzed. The largest faculty was selected for the study. Over the course of 10 years, during the period of Federal State Educational Standard-3, the number of students at this faculty increased from two streams in the 2012-2013 academic year (300 people) up to four streams in the 2022-2023 academic year (700 people). Attestation in the discipline takes place in the form of a written test with an assessment (exam). Statistical processing of data on exam results and rating scores in the semester was carried out in the Microsoft Excel 2019 program. The obtained indexes are presented as arithmetic mean values and standard error of the mean (M±m).Results. Pearson's r-correlation coefficients were calculated to assess the linear relationship of variables: the percentage of correct answers in the exam ticket, the final student rating in the semester, the exam rating, the certification grade. To test the hypothesis about the effectiveness of the chosen teaching methodology, Pearson's test of agreement (χ2 ) was calculated for the sample size of students (n ≥ 100). The pedagogical process carried out in teaching chemistry to first-year students of the medical and preventive faculty is a complex system that includes target, content, activity, performance, resource components. The activity component of the organization of the pedagogical process was modified as follows: a new form of the examination card was developed, as close as possible to the form of control materials for the unified state exam in chemistry, the structure of the practical lesson was rationalized, and a new laboratory workshop was created and tested. The results of the exam in chemistry were analyzed using Pearson's goodness-of-fit test at a significance level of p<0, 05 in two groups of questions: 1 - on topics covered by a laboratory workshop and 2 - on topics not provided with laboratory work. The rating indexes of students when performing tasks related to the first group of questions are significantly higher than in the second group. ><0,05 in two groups of questions: 1 - on topics covered by a laboratory workshop and 2 - on topics not provided with laboratory work. The rating indexes of students when performing tasks related to the first group of questions are significantly higher than in the second group.Conclusion. When using an optimized laboratory practice in chemistry, the most rational form of the lesson is chosen, in which laboratory experiments are included. Comprehensive planning of such classes is carried out differently. The didactic tasks of the lesson are subordinated to highlighting what is essential in the content of the educational material. The presence of an optimized workshop significantly contributes to the choice of the most effective methods and forms of training for a given lesson, leading to an increase in student performance. It is shown that the updated form of the laboratory workshop in chemistry, along with the rationalization of the structure of the lesson and the form of the exam make it possible to achieve maximum learning outcomes with a limited time interval for classroom work. The new form of the examination card, along with the modernized practicum, contributed to the high marks in the exam. It is shown that a properly organized form of passing the exam allows you to adjust the progress of each student and set an objective assessment in chemistry.

Pedagogical Activities of Graduate (1916) of Riga Polytechnic Institute Jānis Rupais (1889–1974) in Latvia

The research on Jānis Rupais (1889–1974), engineer, pedagogue, and graduate of the Department of Chemistry (1916) of Riga Polytechnic Institute (RPI), was conducted using the documents of the National Archives of Latvia, the Latvian State Historical Archive and the Latvian State Archives, as well as Gulbene Municipality Museum of History and Art. The article about the well-known pedagogue in Latvia in the 20th century – the long-term and only Principal of Gulbene State Commercial School and Vocational School (1926– 1944) J. Rupais also reflects on his activities after World War II at Riga Industrial Polytechnicum. It describes both the educational institutions, the principal and pedagogue J. Rupais and his work methods, and the contribution he made to Gulbene and Latvia.

Exploring Chemistry Teacher’s TPCK in Rasch Model: A Point of View from Difference of Teaching Stage, Gender, and Ages.

Teachers should have different knowledge types including technological, pedagogical, and content to realize effective learning in the digital era. Technological Pedagogical and Content Knowledge (TPCK) is a framework that explains these knowledge types and the interactions between them. It is considered to enable chemistry teachers’ multifaceted teaching. Coping, for this reason, a study to examine chemistry teachers’ level of TPCK is needed. This paper reports the level of chemistry teacher’s TPCK and their perception in terms of teaching stage, gender, and age. The study involved fifty-three students of chemistry education in a public university in Indonesia. A quantitative method was applied to explore their perspective on TPCK. Data were collected through surveys and interviews. The findings showed that the majority of chemistry teachers’ TPCK skills are currently good. They integrate technology into their teaching while conducting online learning due to the COVID-19 pandemic. In terms of teaching stage, age, and gender, provide deep insight into seven indicators of TPCK. However, some indicators still need to be improved, so a TPCK training program for individuals or centralized individuals should be added to the chemistry department program.