Preliminary Study on the Mechanical Activation and High‐Temperature Treatment of Saponite‐Containing Tailings Generated during Kimberlite Ore Dressing

This study investigates transformations of a pre-mechanically activated saponite-containing material with subsequent high-temperature treatment. The thermogravimetric analysis confirmed that the mechanical activation of saponite leads to the destruction of its layered structure, accompanied by the release of silicon dioxide and magnesium oxide in free form. The values of surface activity for mechanically activated saponite-containing material are also calculated. It is shown that when mechanically activated saponite-containing material is mixed with water, minerals of the serpentine group are formed, and further high-temperature treatment leads to the formation of minerals of the olivine group. It is experimentally shown that high-temperature treatment leads to the creation of a more durable structure of the saponite-containing material. This is due to decreased porosity and pore size, and sorption of moisture from the environment is also reduced. The study showed that saponite-containing waste materials can be effectively treated to create composite materials based on magnesia binders. Thus, with this method, the waste is effectively recycled into various green building material and can be used as supplementary cementitious material or fine aggregate replacement in concrete

The role of students’ individual work in the formation of professional competences of future doctors.

Modern requirements for training of high-skilled specialists require the implementation of international medical and educational standards in the educational and integrative process. Formation of cognitive activity, pursuance of professional development, the necessity to correspond to world standards medical students’ of gained knowledge. Medical students’ individual work is very important for medical students’ education because it helps to systematize and use knowledge that was gained in practical classes. The aim of the work – to analyze the forms of students’ individual work, used at in the Department of Internal Medicine 2 and Phthisiology, in order to improve the educational process and to form the future doctor’s medical judgment, their ability to self-improvement and self-education. The recommended hours attempted for students’ individual work is 90 out of the total of 240 hours assigned to the discipline in teaching the module “internal diseases” for the 5th year students at the Depertment of Internal Medicine 2 and Phthisiology. In studying the discipline of "internal diseases" in the 5th year one of the main tasks of medical student’s occupation training is mastering ability of assimilation on his own, of knowledge and refresh it, and then to use knowledge effectively in the future career. The difference of the individual work lies in the fact that students can study individually choosing the necessary kind of extracurricular activity according to their interests. In addition, the lack of strict grading by the teacher has more advantages compared to practical classes. The curriculum, the teacher’s tasks and methodological materials determine the content of the individual work. The article presents the three main directions of students’ individual work in teaching discipline of "internal diseases" for students of the 5th year as: students’ individual work in classroom learning, students’ individual work individual work under the teacher’s supervision. When discussing the results of individual work, students learn to think critically, communicate with each other, and make their own well-thought-out (educated) decision. Well-structured process of the individual work encourages medical students to its qualitative fulfillment and it is a significant motivation for further professional growth. Significant reserves to increase its efficiency inherent in the use of modern computer technology. Medical students’ individual work should be considered as one of the necessary stages of a modern doctor training. The latest information technologies and individual scientific projects adoption into the educational process leads to efficiency improvement and it forms new future doctor’s professional competences

Adenine and guanine recognition of stop codon is mediated by different N domain conformations of translation termination factor eRF1

Positioning of release factor eRF1 toward adenines and the ribose-phosphate backbone of the UAAA stop signal in the ribosomal decoding site was studied using messenger RNA (mRNA) analogs containing stop signal UAA/UAAA and a photoactivatable cross-linker at definite locations. The human eRF1 peptides cross-linked to these analogs were identified. Cross-linkers on the adenines at the 2nd, 3rd or 4th position modified eRF1 near the conserved YxCxxxF loop (positions 125–131 in the N domain), but cross-linker at the 4th position mainly modified the tripeptide 26-AAR-28. This tripeptide cross-linked also with derivatized 3′-phosphate of UAA, while the same cross-linker at the 3′-phosphate of UAAA modified both the 26–28 and 67–73 fragments. A comparison of the results with those obtained earlier with mRNA analogs bearing a similar cross-linker at the guanines indicates that positioning of eRF1 toward adenines and guanines of stop signals in the 80S termination complex is different. Molecular modeling of eRF1 in the 80S termination complex showed that eRF1 fragments neighboring guanines and adenines of stop signals are compatible with different N domain conformations of eRF1. These conformations vary by positioning of stop signal purines toward the universally conserved dipeptide 31-GT-32, which neighbors guanines but is oriented more distantly from adenines

Marginal abatement cost curve for an ammonia reduction measure in agriculture: the case of Latvia

Received: January 28th, 2021 ; Accepted: May 26th, 2021 ; Published: August 24th, 2021 ; Correspondence: [email protected] the production of grain and livestock–derived agricultural commodities increasing, the agricultural sector has become one of the main sources of ammonia (NH3) emissions in Latvia. In 2018, the agricultural sector contributed to 83% of the total NH3 emissions originated in Latvia (15.46 kt) (LIIR 2020). The EU has already put in place measures to control NH3 emissions. This includes the EU target of reducing ammonia emissions by 21% by 2030 and sets out emission reduction commitments for Latvia. Considering Latvia’s indicative reduction target, the NH3 emission reductions need to be achieved by 2030 (Directive 2016/2284) so that the emissions do not exceed the 2005 level (11.33 kt). Implementing no mitigation measures, Latvia has projected agricultural sector NH3 emissions to be 32.4% higher than those in 2005, and therefore the mitigation of the NH3 emissions from agriculture is important. The research aims to estimate cost-effective NH3 emission reduction measures in agriculture in Latvia. The results of the research represent a marginal abatement cost curve (MACC) analysis, in which we have quantified the potential for reduction for selected NH3 emission mitigation measures in Latvia. A list of the measures has been established taking into account the experience of good agricultural practices in the reduction of NH3 emissions (UN, 2014) and of other European countries as well. The calculations carried out allowed us to group the measures according to their priorities: measures that are cost-effective and with high potential for reduction of NH3; measures that are cost-effective but with low NH3 emission reduction potential; measures that are not cost-effective but with high potential for reduction of NH3; measures that are not cost-effective and with low potential for reduction of NH3. The estimated cumulative (total) reduction of NH3 emissions in Latvian agriculture by 2030, with the implementation of the measures analysed, is equal to 20.08 kt

Present-day Risk of Occasional Extreme Hydrological and Hydrogeological Events

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive

Microorganisms for bioremediation of soils contaminated with heavy metals

Heavy-metal contaminants are one of the most relevant problems of contemporary agriculture. High toxicity and the ability to accumulate in soils and crops pose a serious threat to food security. To solve this problem, it is necessary to accelerate the pace of restoration of disturbed agricultural lands. Bioremediation is an effective treatment for agricultural soil pollution. It relies on the ability of microorganisms to remove pollutants. The purpose of this study is to create a consortium based on microorganisms isolated from technogenic sites for further development in the field of soil restoration in agriculture. In the study, promising strains that can remove heavy metals from experimental media were selected: Pantoea sp., Achromobacter denitrificans, Klebsiella oxytoca, Rhizobium radiobacter, and Pseudomonas fluorescens. On their basis, consortiums were compiled, which were investigated for the ability to remove heavy metals from nutrient media, as well as to produce phytohormones. The most effective was Consortium D, which included Achromobacter denitrificans, Klebsiella oxytoca, and Rhizobium radiobacter in a ratio of 1:1:2, respectively. The ability of this consortium to produce indole-3-acetic acid and indole-3-butyric acid was 18.03 μg/L and 2.02 μg/L, respectively; the absorption capacity for heavy metals from the experimental media was Cd (56.39 mg/L), Hg (58.03 mg/L), As (61.17 mg/L), Pb (91.13 mg/L), and Ni (98.22 mg/L). Consortium D has also been found to be effective in conditions of mixed heavy-metal contamination. Due to the fact that the further use of the consortium will be focused on the soil of agricultural land cleanup, its ability to intensify the process of phytoremediation has been studied. The combined use of Trifolium pratense L. and the developed consortium ensured the removal of about 32% Pb, 15% As, 13% Hg, 31% Ni, and 25% Cd from the soil. Further research will be aimed at developing a biological product to improve the efficiency of remediation of lands withdrawn from agricultural use

The role of MRI in the diagnosis of acute radiation reaction in breast cancer patient

A clinical case with acute radiation reaction of the left breast after organ-preserving surgery with 10 Gy IORT (24.8 Gy) conventional radiation therapy has been presented. Comprehensive MRI examination showed signs of radiation- induced damage to skin, soft tissues and vessels of the residual breast

Pharmacological chaperones for the oxytocin receptor increase oxytocin responsiveness in myometrial cells

Oxytocin is a potent uterotonic agent administered to nearly all patients during childbirth in the United States. Inadequate oxytocin response can necessitate Cesarean delivery or lead to uterine atony and postpartum hemorrhage. Thus, it may be clinically useful to identify patients at risk for poor oxytocin response and develop strategies to sensitize the uterus to oxytocin. Previously, we showed that the V281M variant in the oxytocin receptor (OXTR) gene impairs OXTR trafficking to the cell surface, leading to a decreased oxytocin response in cells. Here, we sought to identify pharmacological chaperones that increased oxytocin response in cells expressing WT or V281M OXTR. We screened nine small-molecule agonists and antagonists of the oxytocin/vasopressin receptor family and identified two, SR49059 and L371,257, that restored both OXTR trafficking and oxytocin response in HEK293T cells transfected with V281M OXTR. In hTERT-immortalized human myometrial cells, which endogenously express WT OXTR, treatment with SR49059 and L371,257 increased the amount of OXTR on the cell surface by two- to fourfold. Furthermore, SR49059 and L371,257 increased the endogenous oxytocin response in hTERT-immortalized human myometrial cells by 35% and induced robust oxytocin responses in primary myometrial cells obtained from patients at the time of Cesarean section. If future studies demonstrate that these pharmacological chaperones or related compounds function similarly in vivo, we propose that they could potentially be used to enhance clinical response to oxytocin

Predictive and prognostic significance of mRNA expression and DNA copies aberrations of ERCC1, RRM1, TOP1, TOP2A, TUBB3, TYMS, and GSTP1 genes in patients with breast cancer

Increasingly, many researchers are focusing on the sensitivity in breast tumors (BC) to certain chemotherapy drugs and have personalized their research based on the assessment of this sensitivity. One such personalized approach is to assess the chemotherapy’s gene expression, as well as aberrations in the number of DNA copies—deletions and amplifications with the ability to have a significant effect on the gene’s activity. Thus, the aim of this work was to study the predictive and prognostic significance of the expression and chromosomal aberrations of eight chemosensitivity genes in breast cancer patients. Material and methods. The study involved 97 patients with luminal B breast cancer IIB–IIIB stages. DNA and RNA were isolated from samples of tumor tissue before and after treatment. Microarray analysis was performed for all samples on high-density microarrays (DNA chips) of Affymetrix (USA) CytoScanTM HD Array and Clariom™ S Assay, human. Detection of expression level of seven chemosensitivity genes—RRM1, ERCC1, TOP1, TOP2a, TUBB3, TYMS, and GSTP1—was performed using PCR real-time (RT-qPCR). Results. The expression of the RRM1 (AC scheme), TOP2a, TYMS, and TUBB3 genes in patients with an objective response to treatment (complete and partial regression) is higher than in patients with stabilization and progression (p < 0.05). According to our results, the presence of a high level of GSTP1 in a tumor biopsy is associated with the low efficiency of the NAC CP scheme (p = 0.05). The presence of RRM1 deletion is associated with complete and partial regression, as for the TOP1 and TUBB3 genes (p < 0.05). Higher rates of metastatic survival are associated with a high level of expression and amplification of the GSTP1 gene (log-rank test p = 0.02 and p = 0.05). Conclusion. Thus, a complex assessment of the chemotherapy’s gene expression is important not only for understanding the heterogeneity and molecular biology of breast cancer but also to obtain a more accurate disease prognosis