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SOLUTION-PROCESSED SNO2 ELECTRON TRANSPORT LAYER: ADVANCEMENT IN FLEXIBLE PRINTED PEROVSKITE SOLAR CELLS
(Nazarbayev University School of Sciences and Humanities, 2024-08) Kiani, Muhammad Salman
The burgeoning field of flexible and printed perovskite solar cells (PSCs) presents a promising future for renewable energy applications, especially in wearable electronics and smart infrastructure. Realizing their potential hinges on developing functional layers processed at low temperatures. Due to its favorable properties, tin oxide (SnO2) has emerged as a potential material for the electron transport layer (ETL). This study delves into synthesizing and utilizing SnO2 quantum dots (QDs) for ETL fabrication in flexible and printed PSCs.
SnO2 QDs are synthesized via a solvothermal method and formulated into aqueous and printable ETL ink solutions with varying QD concentrations. The electrical conductivity of the resultant ETL films largely depends on the concentration of SnO2 QDs in the ETL inks. A compact layer of SnO2 QD-based ETL can facilitate effective electron transfer from the perovskite layer to the transparent conducting oxide (TCO) layer in PSCs. Achieving an ideal thickness of SnO2 QD-based ETL can reduce charge recombination losses and increase charge extraction efficiency in PSCs, thus improving the overall performance of devices. PSCs are fabricated on flexible plastic substrates using the slot-die coating technique. Notably, ETLs fabricated using 2 wt.% SnO2 QD inks exhibit superior performance, yielding high mean power conversion efficiency (PCE) and showcasing a champion device with 10% PCE. This investigation underscores the potential of SnO2 QDs for the scalable production of PSCs. Despite the prevailing use of SnO2 nanoparticle (NP) dispersion solutions in current PSC manufacturing processes, a comparison is made between the as-synthesized SnO2 QDs-based ETL and the SnO2 NP-based ETL inks. Our findings reveal an 11% enhancement in average device performance, attributed to SnO2 QD-based ETLs’ ability to reduce trap states in the perovskite layer and facilitate charge extraction. In conclusion, this scientific work emphasizes the transformative potential of SnO2 QDs in advancing flexible and printed PSC technology. The study contributes to the fundamental understanding of PSCs and paves the way for practical applications in renewable energy generation. Continued research in this domain promises to propel the development of sustainable energy solutions and shape the future of solar technology.
ANALYSIS OF PERIPHERAL BLOOD AND MUCOSAL EOSINOPHILS IN CHILDREN WITH CHRONIC INFLAMMATORY BOWEL DISEASES
(Nazarbayev University School of Medicine, 2024) Ayazbekova, Akbota
Inflammatory bowel diseases (IBDs) comprises Crohn’s disease (CD) and Ulcerative colitis
(UC), both of which pathogenesis is still under research. There were several studies
investigating the role of eosinophil cell activity in the peripheral blood as well as gastrointestinal
mucosa in adults, but there has been limited study in the pediatric population. This study aims to
assess eosinophil activity in peripheral blood and mucosa, and also assess the correlation in
clinical and pathological aspects. The study recruits 96 patients diagnosed with IBDs during the
period from January 1, 2018 till December 31, 2022. Patients' eosinophil counts were compared
at the first presentation. From selected patients 27 were diagnosed with CD and 69 were
diagnosed with UC. Patient’s mean age was 12.4 and 13.1 years, with male to female ratio of
1.25 and 1.3, respectively. Patients groups divided by PBE median to ‘low’ and ‘high’ group,
showed statistical difference in mucosal eosinophils (p-value < 0.05). However, groups divided
by clinical and inflammatory parameters did not show statistically significant differences (p-value
> 0.05). Overall, the study concludes that there is a correlation between eosinophil count in
peripheral blood and colonic mucosa in IBDs diagnosed pediatric patients.
EPIDEMIOLOGY OF PATIENTS WITH HYPERTHYROIDISM IN KAZAKHSTAN BASED ON DATA FROM NATIONAL REGISTRY COLLECTED BETWEEN 2013 AND 2019.
(Nazarbayev University School of Medicine, 2024) Ibrayeva, Zhanel
The excessive secretion and production of thyroid hormone leads to hyperthyroidism, which can be caused by various factors related to function of gland itself, to regulatory part and due to extra-thyroidal factors. The number one cause of hyperthyroidism is body’s self-induced overproduction of thyroid hormone, which is known as the Graves’ disease. Moreover, iodine is an essential component of thyroid hormone, therefore, the imbalance in its concentration in body may cause either hyperthyroidism or hypothyroidism. Kazakhstan is the country in Central Asia, which has various degrees of iodine deficiency across the country, despite government’s effort to solve this problem by adding iodine into the table salt. As the thyroid disorders are serious conditions, the proper study on its epidemiology is required. There is a lack of information on the epidemiological situation in Kazakhstan related to hyperthyroidism. Thus, the objective of this paper is to analyze the data from the nationwide large-pool registry, which was collected from 2013 to 2019. The statistical analysis on prevalence, incidence, all-cause mortality, survival rates and co-morbidities will be performed on the following study using statistical analysis. It is expected that women are more likely to have hyperthyroidism.
RETROSPECTIVE ANALYSIS OF MATERNAL, NEONATAL AND EARLY-LIFE FACTORS IN CHILDREN AFFECTED WITH DIABETES MELLITUS TYPE I
(Nazarbayev University School of Medicine, 2024) Saniya, Kuan
There is a rapid growth in the incidence of Type 1 Diabetes Mellitus (T1DM) in recent years. Several types of environmental factors related to maternal, neonatal and early life may play a role as triggering factors that lead to emergence of the disease in the genetically susceptible individuals. Current evidence demonstrates conflicting results on the factors that can lead to T1DM. The main aim of this study to analyze the effect of factors, such as birthweight for gestational age, mode of delivery, type of feeding and place of residence on developing T1DM. This is case-control study of the patients that were admitted to Somatic Department of Mother and Child hospital at Astana, Kazakhstan. Patients’ guardians were asked to answer questionaries, and medical records were extracted. There were 52 patients with Type 1 Diabetes Mellitus that were listed as cases and 50 patients that were included as controls. Descriptive data include date of birth, sex, place of residence, birthweight, height at birth, week of birth, type of feeding, birth type, allergies, family history and parity. The association between risk factors and T1DM was assessed by logistic regression analysis by calculation of the odds ratios(ORs) and 95% confidence intervals (CIs). In the multivariate analysis length at birth revealed a significant association with T1DM risk in children born taller (Adjusted OR 1.30, p-value 0.036). Weight, gender, birth timing, residency, feeding methods, and delivery mode resulted in no significant association with T1DM risk.
EVALUATION OF OPTIMAL TIME AND PREGNANCY TERMINATION MODALITIES IN PATIENTS WITH DIABETES MELLITUS
(Nazarbayev University School of Medicine, 2024) Gabbassova, Saniya
Background: The poor management of diabetes mellitus (DM) type 1, type 2, and gestational diabetes in pregnant patients is associated with higher risk of adverse outcomes affecting both maternal and neonatal health. Therefore, to reduce the risk of adverse pregnancy outcomes, it is important to determine appropriate time and mode of delivery in patients with DM.
Methods: This retrospective cohort study included 281 patients with diabetes mellitus delivered between 2013-2017. Patients were divided into five groups based on the weeks of gestation at delivery: <37w, 37-37(+6)w, 38-38(+6)w, 39-39(+6)w, and 40-41 weeks. Additionally, based on the mode of delivery: vaginal delivery, cesarean section, induced vaginal delivery, and emergency cesarean section.
Results: Out of 281 patients 49 (17.44%) delivered < 37 weeks and at 37-37(+6)weeks, 63 (22.42%) patients delivered at 38-38(+6)weeks, 82 (29.18%) patients at 39-39(+6)weeks, and 38 (13.52%) patients delivered at 40-41weeks of gestation. According to the mode of delivery, 62 (22.78%) patients had vaginal delivery, 145 (51.60%) had planned cesarean section, 45 (16.01%) patients had induced vaginal delivery, and 27 (9.61%) patients had undergone emergency cesarean section. Patients with preeclampsia (OR 10.73[4.90, 23.55]), chronic hypertension (OR 2.25 [1.17, 4.32]), diabetic nephropathy (OR 4.06 [2.02, 8.18]), and pathologic CTG (OR 5.06 [2.61, 9.80]) were more likely to deliver before 37 weeks. In neonates born preterm the odds of Apgar score < 7 at 5 min (OR 5.06 [1.22, 21.00]), resuscitation (OR 7.84 [3.62, 16.96]), intubation of the lung (OR 4.67 [1.61, 13.56]), use of oxygen mask (OR 7.84 [3.62, 16.95]), broncho-pulmonary disease (OR 4.83 [1.76, 13.26]), and other diseases (OR 3.44 [1.71, 6.93]) were higher. The macrosomia was 2.38 times more likely in babies born at 40-41 weeks. Neonates born at 38-38(+6)w and 39-39(+6)w groups were less likely to have resuscitation (OR 0.13 [0.03, 0.56]), use of oxygen mask (OR 0.06 [0.01, 0.46]). In terms of mode of delivery, in DM type 2 the odds of having emergency CS were 2.68 times higher. The PROM was associated with vaginal delivery, and pathologic CTG with emergency CS (OR 2.50 [0.16, 5.36] and OR 2.76 [1.21, 6.32], respectively). The use of oxygen mask was less likely in babies born by vaginal delivery (OR 0.19 [0.04, 0.80]).
Conclusion: The delivery at 39th week of gestation was common. Participants mostly delivered by cesarean section. Patients with obstetric complications had higher rates of preterm delivery. Neonates born before 37th week were more likely to develop complications. Macrosomia was more common in babies born at 40-41 weeks. Among neonates born at 38th and 39th week resuscitation was less common. Patients with type 2 DM had higher rates of emergency CS. Except for the use of oxygen mask, there was no association between neonatal complications and mode of delivery.
Recommendations: Based on results of the study, for achieving favorable neonatal outcomes the delivery at 38-38(+6) weeks or 39-39(+6) weeks of gestation is recommended.