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VARIATIONS IN THE CHROME SPINEL CHEMISTRY OF A SERPENTINIZED MANTLE SECTION, KEMPERSAI MASSIF, KAZAKHSTAN
No full textCr-spinel, which occurs in a variety of rocks, can serve as a valuable indicator of geological processes and formation conditions. This study focuses on the three serpentinite samples, collected from the Khromtau region, Aktobe which is geologically a part of the Kempirsai massif of southern Urals. All three samples, namely AK-3, AK-4 and AK-6, contain minerals such as olivine, serpentine and chrome spinel, in varying abundance.The mineral chemistry of the chrome spinels obtained using SEM EDS technique yielded similar composition (MgO=9-11.5%; FeO= 22-23%; Cr2O3=54-59%; Al2O3=9.5-12%) except for sample AK-3, which has an increased amount of magnesium (MgO=12.5%) and aluminum (20.95%), indicating that the sample crystallized from a slightly modified magma. However, the presence of olivine with high Mg content (Fo#=0.88-0.92) in all three samples and low magnesium in the chrome spinels in samples AK-4 and AK-6 indicate that spinel samples are almost co-crystallized with olivine. It can be therefore be concluded that serpentinization has not much altered the chrome spinel chemistry and hence can be a potential indicator of the tectonic setting. With the use of various tectonic discrimination diagrams, it can be concluded that these samples belong to supra subduction zone peridotites formed in a volcanic arc environment
Астана әкімдіктерінде әйел мамандарының аздығы: кедергі мен мәселелерді зерттеу
No full textUnderrepresentation of women in civil service poses a great challenge for the inclusivity, gender equality, and political representation of women’s needs and interests in society. Cultural norms and societal pressures exacerbate the situation further limiting women employee’s career aspirations and advancements. In the presence of systematic barriers
perpetuating underrepresentation, promotion of policies that encourage women’s
participation are found to be an effective solution. This work explores the reasons and factors behind the underrepresentation of women in local governments through a qualitative case study of several akimats of Astana city. By interviewing representatives from local municipalities research reveals emerging themes from the experiences and challenges women employees face during their work and advancement to decision-making positions. Results of the study indicate that societal and cultural biases are prominent reasons behind the underrepresentation of women in akimats. Systematic pressure built on the base of male preference and historically developed assigned roles for women was found to be significant in defining the barriers women face during promotion to decision-making positions. Additionally, the study underlines the importance of domestic responsibilities in evaluating factors that influence women’s decision to pursue political careers in Astana akimats
DELIVERY OF BIOMATERIALS WITH CYTOKINES AND GROWTH FACTORS FOR MYOCARDIAL INFARCTION TREATMENT
No full textOne of the crucial and highly specialized organs in the human body is heart. It has limited regenerative and self-healing potential after the event of injury or illness. Therefore, heart transplantation is the primary treatment for end-stage cardiovascular disorders at the moment. Cardiovascular disease, particularly ischemic heart disease, continues to be one of the main causes of mortality worldwide. After a heart attack, the injured cardiomyocytes are lost and replaced with fibrotic scar tissue (Hashimoto et al., 2018). Cardiomyocyte loss has several consequences, for instance, the reduction of ventricular contraction, which triggers more cardiomyocyte loss, pathological cardiac dilatation, and ultimately heart failure. These series of events fall under the term “cardiac remodeling” (Tenreiro et al., 2021). The main objective of many treatments has been to prevent the gradual cardiac remodeling that leads to heart failure. Currently available effective treatments are medications, coronary artery bypass grafting, percutaneous coronary intervention and heart transplantation (Head et al., 2018). This paper aims to describe a treatment protocol that includes the sequential administration of a composite cryogel with specific cytokines and growth factors. Firstly, the cryogel containing interleukin-10 (IL-10) was directly injected intramyocardially immediately after the induction of myocardial infarction, with the aim to target the acute inflammatory response. A second injection of cryogel loaded with vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) was done on day 7 post-MI. The purpose of the second injection was to stimulate tissue regeneration and the formation of new blood vessels (neoangiogenesis). In the cohort treated with Cryogel/GF, the study’s results demonstrated significant myocardial tissue regeneration. Masson’s Trichrome staining verified the echocardiographic findings, which showed decreased fibrotic areas and increased ejection fraction as well as fractional shortening. Therefore, the newly-developed chitosan-based cryogel contains anti-inflammatory and proangiogenic components, making this biomaterial an excellent cargo for the controlled release of therapeutic factors. Consequently, this will significantly improve tissue regeneration post-myocardial infarction.
Hypothesis: cryogel containing IL-10 cytokine and VEGF/FGF-2 growth factors delivered
sequentially will improve cardiac regeneration after MI
EXAMINING THE CORRELATION OF SECONDARY SCHOOL’S COLLEGE COUNSELING SERVICE ON UNIVERSITY READINESS: A QUANTITATIVE STUDY
No full textThis thesis examines the influence of college counseling services on university readiness among first and second-year university students. Utilizing a quantitative survey method, the study collected data from 60 participants across various universities in Kazakhstan and abroad, employing a mix of convenience and purposive sampling techniques. The research focused on assessing how counseling services contribute to aspects of university readiness such as academic preparedness and social integration. The findings indicated that students who actively engaged with college counseling services reported varied levels of readiness, highlighting significant differences based on whether students were attending universities domestically or abroad. Particularly, students aiming for education overseas exhibited higher engagement with counseling services but reported lower satisfaction levels, suggesting a potential mismatch between service provision and the specific needs of these students. Moreover, a substantial proportion of the student sample sought additional external support for university preparation, pointing to perceived gaps in the efficacy of school-provided services. This trend underscores a crucial demand for more specialized and personalized counseling approaches, especially for students pursuing education outside their home countries. The study acknowledges limitations including the small sample size and the non-random sampling method, which may affect the generalizability of the findings. Future research is recommended to involve larger, more diverse populations and to incorporate mixed methods to better capture the complexities of college counseling's impact on university readiness. This thesis may contribute to the understanding of the pivotal role of college counseling services and calls for enhanced strategies to better meet the diverse needs of students transitioning to higher education
EFFECT OF CURING REGIME ON PROPERTIES OF GEOPOLYMER MIXTURES CONTAINING BASIC OXYGEN FURNACE SLAG (BOFS) AGGREGATES
No full textBasic oxygen furnace slag (BOFS) is a by-product material from the steel industry, which might be used as a substitute for the natural aggregates in the construction industry. The issue pertaining to the use of BOFS as an aggregate is the volume expansion in the concrete matrix by Ca(OH)2 (calcium hydroxide) or Mg(OH)2 (magnesium hydroxide) formed by free calcium oxide (f-CaO) and free magnesium oxide (f-MgO) components in BOFS. Mineral sequestration (CO₂ curing) and the geopolymerization technique are potential remedies for the BOFS expansion problem. This research studied the mechanical, durability, and microstructural characteristics of BOFS-based geopolymer mortar under different curing regimes and durations. While flowability and air content are among the fresh properties of geopolymer mixtures, compressive strength, dielectric constant, drying shrinkage, and expansion (1M NaOH solution and water expansion) are the primary focus of the hardened properties and durability of geopolymer mixtures. Scanning electron microscope (SEM) image, Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analysis were carried out to investigate the microstructural properties of geopolymer mortar.
Four different curing regimes were evaluated: air, water, steam, and combined steam and CO₂ curing. It was looked into how various curing times affected the characteristics of the geopolymer mortar based on BOFS: 6- and 12-hours steam curing and 6-, 12- and 24-hours combined steam and CO₂ curing. Additionally, three different BOFS/Sand ratios of 100/0, 75/25, and 50/50 were compared. The test methods started with evaluating the mortar’s fresh properties: flowability and air content.
The fresh property test results indicate that the mixture with a BOFS/Sand ratio of 75/25 has high flowability, and the air content of mortar mixtures increases with the decrease of BOFS content. Furthermore, compressive strength results indicate that steam curing and combined steam and CO₂ curing increase the compressive strength and have a higher dielectric constant value in comparison to ambient air-cured BOFS-based geopolymer mortar. BOFS/Sand ratio of 75/25 and the longer steam and CO₂ curing favored the compressive strength development. However, the BOFS/Sand ratio and duration of steam curing and CO₂ curing do not significantly affect the dielectric constant value.
For drying shrinkage and 1M NaOH and water expansion tests, both steam curing and the combined steam and CO2 curing hindered the excessive drying shrinkage and expansion in 1M NaOH solution compared to air or water-cured mixtures. The water and 1M NaOH expansion characteristic curves underwent less fluctuation for longer steam and CO₂ curing duration. The drying shrinkage was favored by longer steam curing duration. However, it was not affected by CO₂ curing duration.
FTIR spectroscopy, SEM image analysis and XRD results indicated that the geopolymerization of the mixture was more apparent during the steam curing and CO₂ curing in comparison to water curing and air curing regimes. The longer duration of steam and CO₂ curing also promoted the formation of more stable and dense geopolymer matrix structure, due to longer hydration and formation of stable carbonate compounds
EFFECT OF AIR CONTENT, TEMPERATURE, AND SALINITY ON POLYMER DEGRADATION
No full textWith rising global energy demands, the oil and gas sector is tasked with optimizing output from mature oil fields. These fields, once powered by natural pressures for primary production, now yield less due to the limitations of traditional recovery methods like gas and water drives. This necessitates a shift towards secondary and then to enhanced oil recovery (EOR) techniques for better efficiency and economic feasibility. Polymer flooding, a key EOR strategy, improves recovery using water-soluble polymers to enhance water viscosity, addressing inefficiencies such as fingering and channeling within reservoirs. While successfully boosting oil recovery worldwide, this method encounters obstacles including polymer degradation, adsorption issues, and reduced effectiveness, mainly due to the challenging conditions within reservoirs such as varying oxygen levels, temperatures, and salinity. These environmental factors critically affect the performance and success of polymer flooding.
This research investigates the impact of adding specific ions to brine on polymer viscosity and stability in oil recovery processes, particularly polymer flooding.
The whole experimental part of this research was divided into three steps, which are rheology test, thermal stability test and oil displacement test. During the rheology test, the difference in viscosity values of polymer solutions prepared on different brine compositions was analyzed. On the thermal stability test, the effect of air and nitrogen injection, effect of additional ions on the ability of polymer to withstand the higher temperature for the long period between 14 and 60 days can be observed. Finally, oil displacement test was conducted, with the optimized brine composition for polymer preparation, to see how the optimization of brine composition improves the recovery.
It was found that while calcium chloride (CaCl2) negatively affects polymer viscosity, sodium sulfate (Na2SO4) enhances it, especially in the presence of other ions, indicating that overall salinity is a crucial factor in polymer behavior. Notably, Na2SO4 protects polymers from oxygen-induced degradation, suggesting that oxygen removal, which requires additional facilities, might not be necessary. Long-term thermal stability tests showed that polymers with added Na2SO4 are more stable and less sensitive to oxygen presence. The optimal combination of 4 doses of Na2SO4 and 2 doses of CaCl2 was identified, leading to the most stable polymer with the highest viscosity and lowest degradation. This optimal solution demonstrated improved oil recovery in displacement tests, with 4.6% of additional recovery per each injected PV, compared to 2.9%/PV for the polymer solution prepared on standard CSW, although, total recovery factor at the end of polymer flooding stage was 90% of OOIP. It happens due to negatively charged sulfate ions reducing attraction between the polymer and formation rock walls, thus maintaining polymer structure stability. These findings highlight the potential of optimized ion concentrations in enhancing polymer flooding efficiency
EFFECT OF HYPOCALORIC DIET ON FAT MASS AND LEAN BODY MASS IN POSTMENOPAUSAL WOMEN: A META-ANALYSIS
No full textIntroduction
Postmenopausal women experience significant physiological changes that are associated with an increased risk of metabolic disorders and cardiovascular health risks. One of the strategies to address this issue is to modify dietary intake in response to these changes to maintain health and quality of life. A hypocaloric diet, which involves reduced calorie intake without malnutrition, has been stated as a strategy to target body composition to optimise health outcomes. The objective of this study is to provide a comprehensive assessment of the effectiveness of hypocaloric diets by systematically reviewing the data on the effect of these diets on weight, fat mass, and lean body mass in postmenopausal women.
Methods
A quantitative, systematic review and meta-analysis were conducted. Studies were searched in Pubmed, Web of Science, and Embase databases for relevant studies. Overweight or obese, healthy postmenopausal women that were investigated on the effects of a hypocaloric diet alone in comparison with control groups were included. Meta-analyses were conducted on the outcomes that assessed changes in weight, fat mass, and lean body mass using a random-effects model.
Results
Six studies and nine interventions with 564 participants were included in the meta-analysis. Dietary intervention groups had significantly greater weight, fat mass, and lean body mass loss than control groups (weight difference in means -4.83, 95% CI, -6.01 to -3.66, P < 0.001; fat mass difference in means -2.94, 95% CI, -3.87 to -2.01, P < 0.001; lean body mass difference in means -1.46, 95% CI, -1.87 to -1.05, P < 0.001). A moderate to high level of heterogeneity was present in all three meta-analyses (weight: Q=30.96, P < 0.001, I2= 73.85%; fat mass: Q=20.98, P < 0.001, I2=82.98%; lean body mass: Q=20.67, P < 0.001, I2=65.40%).
Conclusion
Postmenopausal women who followed a hypocaloric diet experienced a reduction in weight and fat mass compared to those in the control group. However, the hypocaloric diet did not meet our hypotheses on increasing lean body mass, as the intervention only included a diet without any exercise, implying the use of stored fat and occasionally muscles
EXPLORING THE ROLE OF CHATGPT IN LANGUAGE AND LITERACY PRACTICES IN AN EMI UNIVERSITY: VOICES OF KAZAKHSTANI STUDENTS
Get PDFArtificial intelligence (AI) technologies rapidly evolve and revolutionize various domains, including higher education. Due to the recent emergence of generative artificial intelligence (AI) large language models (LLM), its potential benefits and challenges are leading debates and concerns about ethical issues. Thus, these concerns influence higher education policies, which either restrict or ban the use of AI tools. Although various research studies have focused on AI’s impact on the English as a foreign language (EFL) field, AI’s role as a language strategy has not been deeply explored in relation to literacy practices. In addition, academic reading and writing with AI are frequently examined from a skills-based perspective focusing on cognitive aspects of literacy, which do not recognize the students’ literacy events and literacy practices shaped by different factors such as culturally valued practices and EMI implementation. Therefore, the study draws on Street’s (1984) literacy as a social practice theoretical framework to explore the influence of institutional and social practices on how foundation-year university students use ChatGPT, one of the most frequently used and advanced AI tools, for literacy practices from student perspectives. The study also focuses on students’ language learning strategy use, employing Oxford’s (1990) classification to identify how they utilize AI for language learning.
This study adopted a qualitative phenomenological research design. Data were obtained from nine foundation-year students at an EMI university in Kazakhstan through diverse data collection instruments, including focus group interviews, two art-based research instruments (image-based reflections and significant circles), and qualitative questionnaires. The findings of this study revealed that foundation-year students have positive and negative perspectives about using ChatGPT. The results also indicated that foundation-year students used AI to socialize and navigate the EMI university’s institutional and social literacy practices in various ways. Moreover, the study found that foundation-year students used ChatGPT as a language strategy, which results from the influence of institutional and social literacy practices. The findings of this study may provide insights to policymakers and university instructors about how foundation-year students utilize AI for literacy practices and how it can foster students’ socialization to literacy practices. In addition, this study may offer language teachers a perspective of artificial intelligence’s potential in scaffolding student learning
60 GHZ PHASED ARRAY PHASE SHIFTER DESIGN FOR 5G APPLICATION
No full textThe purpose of this research work is to design a phase shifter and antenna for integration into a 60 GHz phased array transceiver designed specifically for 5G applications. A phased array transceiver consists of an active device (e.g. amplifier), phased array matrix, and antenna. This thesis focuses on the design of a 60 GHz phased antenna array with no active device. A butler matrix is implemented for the phased array matrix. In the methodology part, the development process of the butler matrix and patch antenna is presented.
In this study, various types of beamforming networks are examined and written in the literature review section. The fundamental components of the Butler matrix are systematically designed, showing each step of the process. At the implementation step, CST software was used. Design is implemented on a substrate material known as Rogers RT/duroid 5880, with a 0.127 mm thickness. The results indicate the good reflection coefficient at the operating frequency of 60 GHz. Proposed design with patch antenna results in four orthogonal beams, each directed at +5°, +37°, -37°, and −5°
REGULATORY IMPACT ASSESSMENT IN GEORGIA, KAZAKHSTAN, AND RUSSIA: POLICY LEARNING AND POLICY CAPACITY
No full textThis dissertation explores the implementation of Regulatory Impact Assessment (RIA) reforms in Georgia, Kazakhstan, and Russia through the lens of policy learning and policy capacities. The study aims to explain the implementation gap between the de jure stated and de facto implemented RIA reforms in these countries. The empirical analysis focuses on measuring the implementation gap using an embedded mixed-method approach, where the quantitative scorecard technique on the quality and analytical depth of RIA reports is embedded within a qualitative explaining outcome causal process-tracing method based on semi-structured interviews and participatory observation notes.
The research reveals that the quality of RIA reports has not improved over time in the study countries. Despite the horizontal and vertical diffusion of RIA reforms, the predominant hetero-hierarchical learning mode resulted in perfunctory RIA implementation in Russia. The advisory nature of oversight body review limits the effective enforcement of RIA quality in Russia. The study attributes moderate success in RIA implementation to the mandatory nature of the oversight body review in Kazakhstan. Georgia, despite international support, demonstrates a failure in epistemic learning mode, leading to low RIA institutionalization.
These findings have significant implications for understanding how RIA reforms can be better implemented and improved. The study underscores the need for stronger political commitment and enhanced accountability mechanisms for policymakers and practitioners. The comparative analysis sheds light on the importance of learning modes and institutional contexts in shaping the effectiveness of regulatory reforms. Consequently, this research provides valuable lessons for other countries seeking to enhance their regulatory frameworks and improve their business environments through effective RIA implementation