Science and Technology - Bachelor's theses

Selle kollektsiooni püsiv URIhttps://hdl.handle.net/10062/99557

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Nüüd näidatakse 1 - 20 48

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Characterization of HEMK2 in nuclear shape regulation
(Tartu Ülikool, 2026) Raimkul, Adiya; Mutso, Margit, juhendaja; Brūmele, Baiba, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Nuclear morphology is a widely used characteristic in clinical diagnostics, and alterations in nuclear shape are associated with a variety of disorders. Nuclear shape is determined by multiple factors, including intranuclear proteins, cytoplasmic forces, and genome organization. Recent studies have suggested that epigenetic regulation by methyltransferases may also influence nuclear shape. HEMK2 is a Class I methyltransferase that is associated with translation termination, cell proliferation, gametogenesis, and various diseases, including cancer and neurological disorders. Although some methyltransferases are associated with nuclear shape, no similar link has previously been reported for HEMK2. Therefore, the main purpose of this study was to investigate whether HEMK2 affects nuclear shape in U2OS cells. The results of this study suggest that HEMK2 is associated with nuclear shape abnormalities, as evidenced by nuclear invaginations in HEMK2-depleted cells. Additionally, lamin A/C expression level was shown to be altered among cell lines. Lastly, HEMK2 was reported to be predominantly cytoplasmic in U2OS cells. In summary, this study suggests that HEMK2 is associated with nuclear morphology in U2OS cells, and this association may be independent of HEMK2's methylation function.
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Electrode materials for water splitting in alkaline electrolysis
(Tartu Ülikool, 2026) Ivashyna, Anastasiya; Grozovski, Vitali, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Alkaline water electrolysis is a leading pathway to renewable hydrogen production, yet conventional immersed-electrode systems are constrained by bubble-induced mass transport losses and sluggish reaction kinetics. This study investigates NiMo cathodes and NiFe anodes fabricated by galvanostatic electrodeposition onto stainless steel mesh substrates (#300 and #400) for operation in a capillary-fed electrolysis cell, which supplies electrolyte via capillary action through a porous separator, enabling near bubble-free operation. The influence of mesh geometry, fluoropolymer chemistry (PTFE vs. PVDF), coating morphology, gas removal efficiency, and full-cell performance was evaluated in 1 M KOH. SEM and EDS confirmed Volmer–Weber island growth on both substrates, with the #400 mesh supporting higher nucleation density and more uniform elemental distribution. Three-electrode measurements showed NiMo reduces η10 by 222 mV and NiFe reduces η100 by 72–79 mV relative to uncoated #400 substrates. In full-cell testing, the #400 PTFE configuration achieved 1.85 V at 0.5 A and 2.18 V at 1.5 A, compared to 2.49 V at 1.5 A for the polymer-free baseline. Post-operation EDS revealed severe Mo leaching in NiMo cathodes and beneficial Fe enrichment in NiFe anodes consistent with active NiFeOOH reconstruction. The results demonstrate that full-cell performance is governed by the interaction between mesh pore geometry and fluoropolymer surface energy rather than intrinsic catalyst activity alone, with the #400 mesh paired with PTFE identified as the optimal configuration within the tested parameter space.
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Regulation of NF-κB-mediated inflammatory responses by miR-378a-3p in 3D epidermal model
(Tartu Ülikool, 2026) Civciša, Anna; Periyasamy, Kapilraj, juhendaja; Rebane, Ana, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
miR-378a-3p has previously been shown to be upregulated under the inflammatory stimulus and in psoriatic skin lesions, suggesting a possible role in psoriasis-associated inflammatory signalling. Previous studies have used two-dimensional (2D) keratinocyte culture model and reported that miR-378a-3p activates NF-κB signalling, resulting in increased CXCL8 (IL-8) expression. However, the effects of miR-378a-3p in differentiated keratinocyte culture models have not previously been investigated. Therefore, this thesis focuses on analysing the role of miR-378a-3p in three-dimensional (3D) keratinocyte culture models by comparing its effects on inflammatory gene expression in conventional 2D and differentiated 3D keratinocyte cultures. The study examined the effect of miR-378a-3p transfection on inflammatory gene expression, with particular focus on NF-κB pathway. In the course of the study, expression levels of CXCL8 expression and selected NF-κB-associated genes (TRAF6, NFKBIA, and EGFR) were evaluated under both unstimulated and IL-17A-stimulated conditions. In addition, the effect of miR-378a-3p transfection on keratinocyte differentiation- and proliferation-related genes (KRT5, KRT14, KRT10, and INV) were investigated. The obtained results demonstrated distinct effect of miR-378a-3p between 2D and 3D culture system. In 2D cultures, miR-378a-3p increased CXCL8 expression, consistent with previously reported pro-inflammatory effects. In contrast, differentiated 3D cultures showed reduced CXCL8 expression together with downregulation of TRAF6 and EGFR following miR-378a-3p transfection. Overall, the findings suggest that the effect of miR-378a-3p may depend on differentiation state and culture conditions.
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Development of Taï Forest alphavirus trans-replicase assay systems in mammalian and insect cells
(Tartu Ülikool, 2026) Shabanova, Evgeniya; Koit, Sandra, juhendaja; Merits, Andres, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Taï Forest alphavirus (TALV) is a poorly characterised insect-specific alphavirus that has remained difficult to study since its discovery due to its inability to grow in standard cell cultures. This study investigates the TALV by developing a mammalian and insect cell-based trans-replicase assay system. To develop the assay, plasmids separating viral replication into two functional components, the replication driver (replicase) and the replication template (minigenome), were constructed and tested by transfection into respective cell lines. The trans-replicase and split trans-replicase systems were used to investigate the compatibility of the TALV minigenome with replicases of other alphaviruses and vice versa. These results offer the first functional analysis of TALV replication, revealing that it is temperature-sensitive and dependent on unknown factors. This insight establishes a baseline for future studies of this understudied alphavirus.
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mRNA-based CAR-T Cell Engineering via Antibody-Conjugated Lipid Nanoparticles
(Tartu Ülikool, 2026) Planken, Henri; Mahlakõiv, Tanel, juhendaja; Shahpazir, Ana, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
This thesis investigates the use of lipid nanoparticles (LNPs) for chimeric antigen receptor (CAR) mRNA (messenger RNA) delivery to T cells as a non-viral approach for cell engineering. Experiments assessed LNP uptake across different cell types and demonstrated minimal uptake in T cells. To address this limitation, antibody-conjugated LNPs were used to enable efficient delivery to T cells. Transfection efficiency was evaluated using GFP reporter mRNA as well as CAR expression detected via an FMC63 idiotype antibody. Functional activity was assessed through co-culture killing assays against CD19-positive Nalm6-GFP target cells across multiple effector-to-target (E:T) ratios. The results demonstrate antibody-conjugated LNPs enhance mRNA delivery to T cells and enable the generation of functional CAR-T cells capable of mediating tumour cell killing.
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Gen2PhenSim: a configurable genotype to phenotype simulator
(Tartu Ülikool, 2026) Chaharna, Kateryna; Güler, Merve Nur, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Genotype-phenotype studies often lack known ground truth, making it difficult to evaluate whether statistical or machine-learning methods recover the true causal architecture of a trait. In this thesis, an existing genotype-phenotype simulation codebase was extended and refined into Gen2PhenSim, a configurable Python-based simulator that generates binary and quantitative phenotypes from real genotype data under user-defined genetic architectures. The simulator supports additive SNP effects, dominant and recessive encodings, second- and third-order interaction terms, Gaussian noise, and quantitative-trait heritability control. Besides, it has a feature to control for selecting SNPs based on their distance to select independent SNPs. As a proof of concept, simulated phenotypes were analysed with Regenie and GWAS hits were compared with the true simulated causal SNPs.
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Development of low-level control system for the KuupKulgur rover
(Tartu Ülikool, 2026) Turchak, Kateryna; Tammer, Andres Aleksander, juhendaja; Tepandi, Tarvi, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Modern extraterrestrial exploration relies on unmanned planetary rovers capable of conducting experiments on cosmic bodies autonomously. This work is a part of the Estonian microrover project KuupKulgur, a lunar explorer which requires a low-level control system for on-board motors as a part of its larger autonomy software stack. This thesis presents development of the control system for the rover’s 6 skid-steering wheels by implementing and enhancing a per-wheel PID controller. The algorithm is configurable to match frequent system improvements and constantly changing requirements of the project. It is developed as a Robot Operating System (ROS) node written in C++ to be easily integrated into the project’s ROS architecture. PID controller utilizes wheel encoder data for control input calculation, and features terrain adaptation and per-wheel correction logic aimed at handling terrain inconsistency. The control system was extensively tuned and tested on several surfaces including lunar regolith analogue at Tartu Observatory, with results presented in this thesis.
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Brain-derived neurotrophic factor profiles in type 1 diabetes: a comparison between patients with and without ketoacidosis
(Tartu Ülikool, 2026) Mazure, Liva; Tagoma, Aili, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Type 1 diabetes (T1D) is a common metabolic autoimmune disease, especially in young people. It is often accompanied by several comorbidities and complications, including diabetic ketoacidosis (DKA), a serious acute metabolic disorder, which can cause neuronal alterations. Brain-derived neurotrophic factor (BDNF) is a neurotrophin involved in neuronal function and metabolic regulation, suggesting a potential association between BDNF and DKA. The aims of this study were to evaluate the associations between BDNF and DKA in individuals recently diagnosed with T1D, assess longitudinal changes in BDNF levels in samples collected 1–3 years after T1D diagnosis, and identify clinical covariates associated with BDNF levels. BDNF levels were measured from serum samples with the ELISA method. No statistically significant association between DKA and BDNF was found at either timepoint and the BDNF level remained stable in follow-up samples. Covariates associated with the level of BDNF included the presence of enterovirus IgG and IgA antibodies, the presence of GAD autoantibodies, C-peptide and IFN-γ levels, male sex, and ketonuria. In conclusion, BDNF levels in T1D were not associated with DKA and remained stable during the first years after diagnosis. BDNF could be more closely connected with immunological and metabolic factors relevant to T1D.
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Expression patterns of ataxia-associated genes during human cerebellum development
(Tartu Ülikool, 2026) Roy, Mariya; Sepp, Mari, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Ataxias are a heterogeneous group of neurological disorders, most commonly arising from dysfunction or degeneration of the cerebellum, a part of the brain that plays critical roles in motor control. Many forms of ataxia have genetic causes and more than a hundred genes are considered to be associated with hereditary ataxias. This study explores the expression patterns of ataxia-associated genes during human cerebellum development, using bulk and single-nucleus RNA-sequencing datasets. Results demonstrate that ataxia-associated genes show higher expression during cerebellum development compared to other organs. The expression of these genes increases during cerebellar development and cellular differentiation, and is particularly high in Purkinje cells. Genes associated with autosomal dominant ataxias show greater cerebellar and Purkinje cell specificity compared with genes associated with autosomal recessive ataxias. These findings contribute to our understanding of the developmental and cell type-specific mechanisms underlying ataxias.
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The role of HvSnRK2.7 and HvSnRK2.9 in stomatal regulation of barley
(Tartu Ülikool, 2026) Klavina, Marta; Merilo, Ebe, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
This thesis investigated the role of barley SnRK2 kinases HvSnRK2.7 and HvSnRK2.9 in stomatal regulation using two double mutant lines, L15 and L20, and the wild type cultivar Golden Promise. Gas exchange measurements with Licor-6800 showed that mutant plants had higher stomatal conductance and slower stomatal closure in response to reduced relative air humidity compared with wild type plants. Mutants also maintained more stable net CO₂ assimilation under low humidity conditions. No significant differences in stomatal density were detected, indicating that the altered stomatal regulation was caused by changes in stomatal aperture rather than stomatal development. Increased stomatal conductance was also observed in awns and leaf sheaths, suggesting that HvSnRK2.7 and HvSnRK2.9 regulate gas exchange in multiple above-ground organs. Overall, the results demonstrate an important role for these SnRK2 kinases in barley stomatal regulation and responses to atmospheric humidity. Higher stomatal conductance and associated rise in photosynthesis may result in yield gains in well-watered conditions.
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Genetic and molecular factors affecting vitamin B12 levels in Estonian Biobank
(Tartu Ülikool, 2026) Belkouraichi, Mouna; Abner, Erik, juhendaja; Batool, Kanwal, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Vitamin B12 is an essential micronutrient involved in DNA synthesis, red blood cell formation, and neurological function. Low levels of vitamin B12 are associated with a variety of clinical conditions, including pernicious anemia, serious neurological problems, and cardiometabolic diseases. In this study, we analyzed circulating vitamin B12 levels in 74,669 participants from the Estonian Biobank using a genome-wide association study. Associated single-nucleotide variants were annotated to identify genes and molecular mechanisms related to vitamin B12 transport and metabolism, with additional focus on coding variants of potential biological relevance. From this analysis, we identified 26 genome-wide significant loci comprising 8,876 candidate variants that mapped to the vicinity of 527 genes, with the strongest signals in genes involved in vitamin B12 transport, absorption and metabolism. These findings expand our understanding of genetic factors affecting circulating vitamin B12 levels, and provide a structural basis for understanding how specific genetic coding variants may affect the transport molecular mechanisms of vitamin B12 transport.
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Engineering and validation of single-cycle alphavirus replicon particles
(Tartu Ülikool, 2026) Aliyeva, Natavan; Väljaots, Evelin, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
MAYV, RRV, ONNV, and BFV are understudied alphaviruses, often investigated using tools developed for model viruses, such as SINV and CHIKV. This study aimed to develop and evaluate VRP systems for a panel of alphaviruses using ZsGreen and mCherry reporter replicons and a split-helper system in BHK-21 cells. The VRPs were analysed by second-round infection using fluorescence microscopy. The results showed that VRP production differed between alphavirus backbones. SINV and MAYV produced relatively high titers of VRPs, whereas RRV and BFV were less efficient. Removal of the capsid enhancer sequence improved ONNV VRP production but reduced RRV VRP titers and abolished detectable BFV VRP titers. Second-round infection confirmed that the generated VRPs were single-cycle. Overall, this thesis demonstrates that alphavirus VRP production is virus-specific and that regulatory elements optimised for model alphaviruses cannot be assumed to function universally across the genus.
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Characterizing the genomic diversity of prevalent gut microbiome bacterial species using metagenome-assembled genomes
(Tartu Ülikool, 2026) Kholonivskyi, Oleksandr; Pantiukh, Kateryna, juhendaja; Krigul, Kertu Liis, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Metagenome-wide association studies enable the identification of associations between the human microbiome and host physiological traits, such as inflammatory bowel disease, type 2 diabetes, and mental disorders, as well as many other physiological features, including diet, stress, exercise, and drug intake. In these studies, microbiome composition is typically characterized at the species level. As the gut microbiota is known to exhibit structured diversity below the species level, association studies at the within-species level may yield stronger associations. A major challenge is that the within-species structure of most gut microbial species remains poorly defined. In this study, we investigated the within-species structure of the five most abundant and prevalent microbial species using open data. The results showed clear within-species structures for four of the five species.
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Cell-penetrating peptides for in vitro delivery of small interfering RNA and splice-correcting oligonucleotides
(Tartu Ülikool, 2026) Khrystynchenko, Polina; Porosk, Ly, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Optimization of carrier systems is required to enhance the development of nucleic acid therapies. Cell-penetrating peptides (CPPs) are promising transport vectors for this purpose, which can form nanoparticles with therapeutic nucleic acids and facilitate their transport to intracellular targets. As part of this work, the potential of five amphipathic PepFect14-based CPPs complexed with small interfering RNA (siRNA) and splice-correcting oligonucleotides (SCOs) was studied in the formation of nanoparticles and the delivery of nucleic acid into the cell. All new analogs tested formed CPP-nucleic acid complexes with both siRNA and SCOs. In addition, the stability of CPP/siRNA nanoparticles was tested against enzymatic degradation and polyanionic heparin. The four analogs possessed a suitable profile as siRNA transport vectors, while only two analogs were suitable as tested under the given conditions for both siRNA and SCO. None of the CPP/siRNA and CPP/SCO nanoparticles tested had a significant impact on cell viability.
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Investigating the genetic and ancestral diversity of an immune response locus
(Tartu Ülikool, 2026) Polishchuk, Sofiia Stefaniia; Dannemann, Michael, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Neanderthal introgression is known to affect a variety of traits of modern humans, including immune response. Specifically, genes involved in defense against RNA viruses have been shown to be enriched in Neanderthal ancestry. However, less is known about the impact of archaic admixture on response to DNA viruses. In this study we investigate the genetic and ancestral diversity of a locus linked to increased measurements of viral load in blood of Epstein-Barr virus. To do this we utilized genomic data from present-day populations, an archaic introgression map and genome-wide association summary statistics for EBV load in blood. We identified a Neanderthal-like haplotype which carried the highest number of increase-associated alleles. However, several haplotypes of predominantly African ancestry also carried a small proportion of increase-associated alleles. We found that the local lead SNP segregates in both the Neanderthal haplotype and in one African haplotype. These findings suggest that Neanderthal introgression is likely not the sole contributor to the virus association signal and that there is notable genetic diversity possibly linked to the GWAS signature at this locus in African populations as well.
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Study of direct current electrocatalytic hydrogen evolution on bismuth (111) electrode in diluted acidic solutions
(Tartu Ülikool, 2026) Abidi, Syed Muhammad Kumail Mehdi; Grozovski, Vitali, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
This thesis investigates the Hydrogen Evolution Reaction (HER) on Bismuth (111) single crystal electrodes in dilute acidic solutions (pH 2.0 to 3.5) to validate a robust chronopotentiometric model that characterizes the transition from proton reduction to water reduction and identifies the specific moment of near-electrode alkalization. Using cyclic voltammetry (CV) for surface characterization and chronopotentiometry to monitor potential transients under constant current, the study demonstrates that HER on Bi(111) is a diffusion-controlled process that is highly sensitive to proton availability. Experimental data analysis revealed that the unified diffusion coefficient (D) decreases with increasing bulk pH, a trend consistent with the Grotthuss mechanism, while the cathodic charge transfer coefficient (αc) increases from approximately 0.74 at pH 2.0 to 0.9 at pH 3.0, suggesting improved electron transfer kinetics in less acidic environments. Ultimately, the research confirms that while Bismuth (111) is an ineffective HER catalyst compared to noble metals due to its weak hydrogen binding and slow Volmer adsorption steps, the proposed mathematical model accurately determines critical kinetic parameters and benchmarks catalytic activity by identifying the exact point of surface pH shifts.
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Investigation of epitranscriptomic regulation in Scribble-mediated epithelial polarity disruption during Drosophila eye development
(Tartu Ülikool, 2026) Rudman, Tamara; Shimmi, Osamu, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Understanding epithelial tissue homeostasis is critical in animal development and disease, with apicobasal polarity (ABP) as a key regulatory mechanism. The ABP determinants, such as Scribble, also function as tumour suppressors, yet their role in growth regulation remains incompletely understood. N⁶-methyladenosine (m⁶A), an epitranscriptomic RNA modification mediated by Mettl3, has recently been implicated in gene regulation during cancer progression, but its role in polarity-loss-driven tumorigenesis is unclear. This study uses the Drosophila compound eye to investigate how altered Mettl3 activity influences tumour progression in scrib mutant cells. Using MARCM-based eyFLP mosaic analysis, scrib mutant clones with Mettl3 knockdown or overexpression were generated, and ommatidial disruption was quantified to assess tissue integrity. Altered Mettl3 expression increased tissue disruption, indicating that m⁶A acts as a modifier of ABP driven morphogenesis.
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Sign language recognition and reasoning pipeline for human-robot interaction
(Tartu Ülikool, 2026) Suzuki, Temma; Vunder, Veiko, juhendaja; Kruusamäe, Karl, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Modern technologies enable seamless interactions between humans and machines through voice recognition, as seen in in-car multimedia systems and smart speakers. Such benefits are not accessible to deaf and hard-of-hearing people. Sign Language Recognition (SLR) translates sign language into text, widening the means of communication. However, many studies primarily focus on improving recognition accuracy, and the solutions are usually not deployed in real life to help people. Additionally, deaf and hard-of-hearing people are usually not well involved in their development or performance evaluation, and this gap has repeatedly raised questions about the real-world applicability of such studies. This thesis aims to develop a sign-language-controllable robot. First, signers sign in front of the robot’s camera, and MediaPipe, a machine learning framework for real-time hand and pose landmark detection, is used to estimate participants’ skeletal models during sign language performance. Then, the SLR model, which recognises American Sign Language (ASL) letters, is utilised to construct sentences letter by letter. Minor distortions are corrected by Gemma 3n, a locally deployed lightweight Large Language Model (LLM). Lastly, Gemma 3n also performs context extraction, and the robot moves accordingly. The entire pipeline was implemented on ROS 2. 15 videos were collected from 3 native signers performing sentences in everyday places such as kitchens and living rooms. The average Character Error Rate (CER) was 0.079, and the plan success rate and execution success rate both reached 1.00. In addition, the in-person user study with one of the native signers in a domestic environment showed that the average CER was 0.254. Despite such circumstances, the plan and execution success rates achieved 0.70. This thesis can be further developed for real-world robot applications to make technologies more accessible to deaf and hard-of-hearing people.
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Functional analysis of bCA1 splice forms in stomatal CO2 responses
(Tartu Ülikool, 2026) Vydzhak, Viktoriia; Wang, Yuh-Shuh, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
Plants tightly control their stomatal apertures to balance CO2 uptake for photosynthesis with water loss through transpiration. Elevated CO2 causes stomata to close, whereas low CO2 triggers stomatal opening. Carbonic anhydrases (CAs) have been implicated as key upstream regulators of guard cell CO2 signaling. Although four different splice forms of bCA1 with distinct subcellular localization have been identified to date, only the longest chloroplast-localized bCA1.2 has been shown to play a role in stomatal CO2 responses. Moreover, there is uncertainty in the literature regarding the localization of different bCA1 splice forms. This thesis aimed to verify the subcellular localization of bCA1 splice forms and determine their role in guard cell CO2 signaling. In addition, we have identified a putative kinase-interaction motif (KIM) in bCA1 and aimed to explore the effect of its disruption on the localization and function of bCA1.3. Our results indicate that splice forms bCA1.2 and bCA1.3 are localized to chloroplasts, whereas bCA1.1 and bCA1.4 are cytosolic proteins. Using transgenic Arabidopsis plants, we demonstrate that all four splice forms can function in guard cell CO2 signaling. Destroying the putative KIM affected both the localization and function of bCA1.3, although the mechanisms behind these effects remain to be elucidated.
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Vision-based human posture and gesture recognition for SemuBot
(Tartu Ülikool, 2026) Keskin, Yigithan; Raudmäe, Renno, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Bioinseneeria instituut
This bachelor’s thesis outlines the design of SemuBot’s real-time human posture and gesture recognition system. SemuBot is the first of its kind social assistive robot from Estonia. Social robots in both healthcare and elderly care environments need strong non-verbal communication skills and opportunistic safety monitoring and socializing features. To provide those features without incorporating wearable sensors, the system utilizes the YOLOv8-pose estimation model in combination with an Intel RealSense D435i depth camera. Heuristic algorithms were created to analyze the spatio-temporal relations of the 17 body keypoints. The recognition system also analyzes the relative heights and wrist position to the width of the shoulders in order to determine waving/assistive gestures. The system also includes an opportunistic mechanism to help classify and monitor temporal velocity and the posture of the user, which identifies and classifies the user as standing, sitting, or laying. Evaluated under the constraints of edge computing, the system is able to address the needs with high accuracy and low latency.

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