黑料不打烊

艩iame bakalauro darbe nagrin臈jama, ar antimitochondriniai ir antinukleariniai antik奴nai gali veikti kaip serologiniai 啪ymenys, atspindintys sunkesn臋 pirmin臋 bilijin臋 ciroz臋. 艩iame tyrime nagrin臈jamas 拧i懦 autoantik奴n懦 buvimas ir titrai, susiejant juos su biocheminiais matavimais ir histologija. Literat奴ros ap啪valgoje i拧samiai apra拧oma kepen懦 liga, jai b奴dingi antik奴n懦 啪ymenys ir bendra kepen懦 histologija. Statistin臈 tyrime dalyvavusi懦 pacient懦 duomen懦 analiz臈 rodo, kad abu autoantik奴nai yra ribotai naudingi kaip potencial奴s ligos sunkumo ir prognozavimo 啪ymenys. Darbo strukt奴ra: 寞vadas, literat奴ros ap啪valga, metodai, rezultatai, aptarimas, i拧vados, literat奴ros 拧altiniai Darb膮 sudaro: 40 puslapi懦 teksto be pried懦, 20 paveiksl懦, 14 lenteli懦 ir 36 bibliografiniai 寞ra拧ai.

This bachelor's thesis examines whether anti-mitochondrial and anti-nuclear antibodies can act as serologic markers that reflect more severe primary biliary cirrhosis. This study examines the presence and titers of these autoantibodies and relates them to biochemical measures and histology. The literature review describes the liver disease, its characteristic antibody markers, and general liver histology extensively. The statistical analyses on data from patients enrolled in the study show that both autoantibodies are limited in utility as potential severity and predictive markers. Thesis structure: introduction, literature review, methods, results, discussion, conclusions, references This thesis consists of: 40 pages of text without appendices, 20 figures, 14 tables, and 36 bibliographical entries.

艩iame magistro darbe tirti nizinu kapsuliuot懦 daleli懦 fizikocheminiai parametrai, vertinant skirting懦 biopolimer懦 tinkamum膮 nizino perna拧os sistem懦 formavimui ir kontroliuojamam atpalaidavimui. Paruo拧tos skirtingos nizino perna拧os sistemos, nustatytas j懦 寞kapsuliavimo efektyvumas, daleli懦 dydis, zeta potencialas, proteolitinis stabilumas bei nekovalentin臈s s膮veikos. Nustatyta, kad sistem懦 stabilum膮 lemia elektrostatini懦, hidrofobini懦 ir vandenilini懦 s膮veik懦 visuma. Kontroliuojamo atpalaidavimo tyrimai parod臈, kad nizino i拧siskyrimas priklauso nuo pH, temperat奴ros, jonin臈s j臈gos ir pasirinkto polisacharido. Kinetini懦 modeli懦 analiz臈 parod臈, kad atpalaidavimo proces膮 daugeliu atvej懦 geriausiai apib奴dina Higuchi modelis, rodantis difuzin寞 atpalaidavimo mechanizm膮. Darb膮 sudaro 7 dalys: 寞vadas, literat奴ros ap啪valga, tyrimo metodika, tyrimo rezultatai ir j懦 aptarimas, i拧vados ir literat奴ros s膮ra拧as. Darbo apimtis 鈥� 73 p. teksto be pried懦, 29 iliustracijos, 4 lentel臈s, 59 bibliografiniai 拧altiniai. 10 pried懦.

This master's thesis investigated the physicochemical parameters of nisin-encapsulated particles, assessing the suitability of different biopolymers for the formation and controlled release of nisin delivery systems. Different nisin delivery systems were prepared; their encapsulation efficiency, particle size, zeta potential, proteolytic stability and non-covalent interactions were determined. It was found that the stability of the systems is determined by the combination of electrostatic, hydrophobic and hydrogen interactions. Controlled release studies showed that the release of nisin depends on pH, temperature, ionic strength and the selected polysaccharide. Analysis of kinetic models showed that the release process is best described in most cases by the Higuchi model, which indicates a diffusive release mechanism. The thesis consists of 7 parts: introduction, literature review, research methodology, research results and their discussion, conclusions and references. The thesis is 73 pages long. text without appendices, 29 illustrations, 4 tables, 59 bibliographical entries. 10 attachments.

Baigiamajame magistro darbe tiriamas fotoliuminescencini懦 aukso nanoklasteri懦 stabilumas 寞vairiose biologin臈se terp臈se ir j懦 poveikis biologiniams objektams. Darbo metu analizuojamos aukso nanoklasteri懦 optin臈s savyb臈s, fotoliuminescencijos intensyvumo kitimas laike bei koloidinis stabilumas distiliuotame vandenyje, Neries up臈s vandenyje, gr臋啪inio vandenyje, 啪uv懦 ikr懦 ir embrion懦 auginimo terp臈se bei dumbli懦 auginimo terp臈je. Taip pat vertinamas nanoklasteri懦 dydis ir pavir拧iaus topografija, naudojant atomin臈s j臈gos mikroskopij膮, bei j懦 kaupimasis biologiniuose objektuose, taikant konfokalin臋 mikroskopij膮 ir Daphnia magna biologin寞 model寞. Darb膮 sudaro 7 dalys: 寞vadas, literat奴ros ap啪valga, metodin臈 dalis, tyrimo rezultatai bei j懦 aptarimas, i拧vados, literat奴ros s膮ra拧as, priedai. Darbo apimtis 鈥� 52 p. teksto be pried懦, 34 iliustr., 6 lent., 47 bibliografiniai 拧altiniai. Atskirai pridedami darbo priedai.

This master鈥檚 thesis investigates the stability of photoluminescent gold nanoclusters in various biological media and their effects on biological systems. The study analyzes the optical properties of gold nanoclusters, changes in photoluminescence intensity over time, and colloidal stability in distilled water, water from the Neris River, deep 鈥� well water, fish egg and embryo culture media, and algae culture media. The size and surface topography of the nanoclusters are also evaluated using atomic force microscopy, and their accumulation in biological objects is assessed using confocal microscopy and the Daphnia magna biological model. The thesis consists of 7 sections: introduction, literature review, methodology, research results and their discussion, conclusions, bibliography, and appendices. The thesis comprises 52 pages of text excluding appendices, 34 illustrations, 6 tables, and 47 bibliographic sources. The appendices are attached separately.

艩iame tyrime buvo i拧grynintas Patatinas - pagrindinis bulvi懦 gumb懦 atsarginis baltymas ir i拧tirta jo s膮veika su chitozanu, siekiant 寞vertinti galimas nano/mikroenkapsuliacijos taikymo galimybes. Jon懦 main懦 chromatografijoje buvo naudojamos skirtingos buferin臈s sistemos, norint pagerinti gryninimo efektyvum膮. Gautos frakcijos buvo analizuojamos SDS-PAGE elektroforez臈s metodu, o baltym懦 grynumas 寞vertintas naudojant 鈥濱mageJ鈥� densitometrin臋 analiz臋. Gryninimo rezultatai priklaus臈 nuo taikytos chromatografin臈s strategijos. DEAE鈫扴P chromatografijos seka parod臈 geriausius rezultatus ir leido pasiekti apie 96 % baltym懦 grynum膮. Tuo tarpu nuoseklus anijon懦 main懦 chromatografijos etap懦 taikymas reik拧mingo gryninimo pager臈jimo nesuteik臈. Galima Patatino ir chitozano s膮veika buvo tirta taikant UV-Vis bei fluorescencin臈s spektroskopijos metodus. UV-Vis spektr懦 analiz臈 parod臈, kad baltymo-polisacharido kompleksai susidaro daugiausia d臈l nekovalentini懦 s膮veik懦. Fluorescencin臈s analiz臈s rezultatai taip pat atskleid臈, kad did臈janti chitozano koncentracija palaipsniui slopino Patatino fluorescencij膮. Tyrimo rezultatai rodo, kad jon懦 main懦 chromatografija gali b奴ti efektyviai optimizuota Patatino gryninimui. Nustatyta Patatino ir chitozano s膮veika taip pat leid啪ia manyti, kad 拧ie kompleksai gali b奴ti pritaikomi maisto technologijose bei b奴simose nano/mikroenkapsuliacijos sistemose.

Patatin, which is the main storage protein in potato tubers, was purified and investigated for its interaction with chitosan in relation to possible nano/microencapsulation applications. Different buffer systems were applied during ion-exchange chromatography in order to improve purification efficiency. The obtained fractions were evaluated by SDS-PAGE electrophoresis, and protein purity was analyzed using ImageJ densitometry. The purification results differed depending on the chromatographic approach used. The DEAE鈫扴P sequence gave the most satisfactory outcome and yielded approximately 96% purity. On the other hand, applying consecutive anion-exchange chromatography steps did not significantly improve the purification level. Possible interactions between Patatin and chitosan were analyzed by UV-Vis and fluorescence spectroscopy. According to the UV-Vis spectra, protein-polysaccharide complexes were formed mainly through non-covalent interactions. Fluorescence analysis additionally demonstrated that increasing chitosan concentration caused gradual quenching of Patatin fluorescence. The study indicates that ion-exchange chromatography can be effectively optimized for the purification of Patatin. The observed interaction between Patatin and chitosan also suggests that these complexes could be useful in future food and nano/microencapsulation applications.

Antibiotikams atsparios bakterijos (AAB) ir antibiotik懦 atsparumo genai (AAG) yra vis da啪niau aptinkami 啪em臈s 奴kio ekosistemose. 艩is paplitimas yra susij臋s su vis did臈jan膷iu antibakteriniu atsparumu, kur寞 lemi膮 atsparumo gen懦 sklaida aplinkoje. Mikroorganizm懦 populiacij懦 gausumo ir atsparumo aplinkos veiksniams tyrimai yra svarb奴s siekiant i拧tirti bendr膮 奴ki懦 ekologin臋 b奴kl臋 ir galim膮 rizik膮 gyv奴n懦 bei 啪moni懦 sveikatai. 艩io tyrimo tikslas 鈥� apib奴dinti i拧 啪em臈s 奴kio aplinkos i拧skirtas antibiotikams atsparias bakterijas, analizuojant j懦 fenotipin寞 atsparum膮, genetinius atsparumo determinantus ir antagonistines s膮veikas, taikant molekulinius ir mikrobiologinius metodus. Tyrime analizuoti 44 i拧 啪em臈s 奴kio aplinkos i拧skirti bakterij懦 kamienai. Jiems taikyti minimalios slopinamosios koncentracijos nustatymo, pasirinkt懦 atsparumo gen懦 aptikimo PGR metodu, plazmid啪i懦 i拧skyrimo ir sek懦 analiz臈s bei antagonistinio aktyvumo vertinimo metodai. Dauginis atsparumas antibiotikams nustatytas 40,9 % izoliat懦. Da啪niausiai nustatytas atsparumas ampicilinui, jis aptiktas 59,1 % izoliat懦. Did啪iausias atsparumo profili懦 pana拧umas nustatytas tarp Klebsiella spp., Lysinibacillus spp. ir Serratia spp. Su buvein臈mis susij臋 pasiskirstymo d臈sningumai rodo didesn臋 bakterij懦 寞vairov臋 奴ki懦 dirvo啪emyje. Atsparumo genas blaTEM buvo aptiktas da啪niausiai - 50 % vis懦 izoliat懦. Plazmid啪i懦 i拧skyrimo metu buvo nustatytos dvi sekos, kurios parod臈 >95 % tapatum膮 anks膷iau apra拧ytoms plazmid啪i懦 sekoms. Atrinkt懦 antibiotikams atspari懦 bakterij懦 izoliat懦 antagoninis aktyvumas buvo nustatytas 15,9 % bakterini懦 izoliat懦 prie拧 devynias biocidini懦 mieli懦 padermes. Did啪iausia slopinimo zona (10,83 mm) buvo nustatyta Solibacillus spp. veikiant mieles Trichosporon dermatis. 艩寞 darb膮 sudaro 寞vadas, literat奴ros ap啪valga, med啪iagos ir metodai, rezultatai ir j懦 aptarimas, i拧vados bei literat奴ros s膮ra拧as. Bendras darbo puslapi懦 skai膷ius be pried懦 鈥� 66, 寞skaitant 10 paveiksl懦, 9 lenteles ir 109 bibliografiniai 拧altiniai.

Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are increasingly detected in agricultural ecosystems. The distribution of abundant microbial populations and environmental resistance is crucial for understanding overall ecological conditions and potential risks to both animal and human health. The aim of this study was to characterize antibiotic-resistant bacteria in agricultural environments by analysing their phenotypic resistance, genetic resistance determinants, and antagonistic interactions using molecular and microbiological methods. A total of 44 farmland-derived bacterial isolates were analysed using minimum inhibitory concentration testing, PCR-based detection of selected ARGs, plasmid extraction and sequence analysis, and antagonistic spot assays. Multidrug resistance was detected in 40.9% of isolates. Ampicillin resistance was the most frequent phenotype, observed in 59.1% of isolates. The highest similarity in resistance patterns was observed among Klebsiella spp., Lysinibacillus spp., and Serratia spp. Habitat-associated distribution patterns indicated greater niche specialization in farmland soil. The blaTEM gene was detected in higher abundance, identified in 50% of all isolates. Plasmid extraction resulted in two putative plasmids, showing >95% identity to previously described plasmid sequences. Antagonistic activity of selected antibiotic-resistant bacterial isolates was detected in 15.9% of the bacterial isolates against nine killer yeast strains. The largest inhibition zone with 10.83 mm was observed for Solibacillus spp. against yeast Trichosporon dermatis. This thesis consists of the introduction, review of the literature, materials and methods, results and discussion, conclusions, and references. Total number of pages without appendixes is 66, including 10 figures, 9 tables, and 109 bibliographical entries.

艩iame magistro darbe nagrin臈jamas viruso daleli懦 jud臈jimas ir j懦 s膮veika su aplinka, ypating膮 d臈mes寞 skiriant aerozolini懦 la拧eli懦 transportui ore bei j懦 s膮veikai su respiratoriumi. Darbo tikslas 鈥� i拧tirti viruso daleli懦 dinamik膮 skirtingose terp臈se ir 寞vertinti fizini懦 j臈g懦 寞tak膮 j懦 jud臈jimui bei nus臈dimui. Tyrime taikomas kombinuotas skaitinio modeliavimo metodas, apjungiantis skys膷i懦 dinamikos (CFD) ir diskre膷i懦j懦 element懦 metodo (DEM) principus. Oro ir la拧elio jud臈jimas modeliuojamas kaip dvikomponentis srautas, taikant Navj臈鈥揝tokso lygtis, leid啪ian膷ias nustatyti grei膷io ir sl臈gio laukus. Taip pat, viruso dalel臈s s膮veika su pavir拧iumi analizuojama naudojant DEM principus, 寞vertinant kontaktines mechanines s膮veikas, tokias kaip elastin臈s, adhezin臈s ir elektrostatin臈s j臈gos. Gauti rezultatai parod臈, kad viruso dalel臈s jud臈jim膮 lemia skirting懦 j臈g懦 s膮veika, kuri kinta priklausomai nuo jud臈jimo stadijos. Laisvo jud臈jimo faz臈je dominuoja aerodinamin臈s j臈gos, o art臈jant prie pavir拧iaus did臈ja kontaktini懦 j臈g懦 reik拧m臈, lemian膷i懦 dalel臈s prisitvirtinim膮. CFD modeliavimas parod臈, kad respiratoriaus filtravimo strukt奴ra reik拧mingai kei膷ia aerozolio srauto charakteristikas, ma啪ina jo greit寞 ir skatina daleli懦 nus臈dim膮, o DEM analiz臈 leid啪ia 寞vertinti dalel臈s mechanin寞 stabilum膮 kontaktin臈je zonoje. Darbo rezultatai leid啪ia kompleksi拧kai 寞vertinti viruso transporto mechanizmus, apjungiant srauto dinamik膮 ir daleli懦 s膮veik膮 su pavir拧iumi. Gauti duomenys gali b奴ti taikomi vertinant apsaugini懦 priemoni懦 efektyvum膮 bei tolesniuose aerozoli懦 sklaidos ir infekcij懦 plitimo tyrimuose.

This master鈥檚 thesis investigates the motion of virus particles and their interaction with the surrounding environment, with a particular focus on aerosol droplet transport in air and interaction with filtration surfaces. The aim of the study is to analyze virus particle dynamics in different media and evaluate the influence of physical forces on their movement and deposition. The study applies a combined numerical modeling approach integrating computational fluid dynamics (CFD) and the discrete element method (DEM). The airflow and droplet behavior are modeled as a two-phase flow using the Navier鈥揝tokes equations, allowing the determination of velocity and pressure fields. The interaction between virus particles and surfaces is analyzed using DEM principles, considering contact mechanics such as elastic, adhesive, and electrostatic forces. The results demonstrate that virus particle motion is governed by the interaction of multiple forces that vary depending on the stage of motion. Aerodynamic forces dominate during the free motion phase, while contact forces become significant near surfaces, determining particle attachment. CFD simulations show that the mask filtration structure significantly alters the aerosol flow, reduces its velocity, and enhances particle deposition, while DEM analysis provides insight into the mechanical stability of particles upon contact. The findings enable a comprehensive evaluation of virus transport mechanisms by combining flow dynamics and particle鈥搒urface interaction analysis. The results can be applied in assessing the efficiency of protective equipment and in further studies of aerosol dispersion and infection transmission.

艩iame magistro darbe nagrin臈jama elektroencefalografijos (EEG) duomen懦 analiz臈, siekiant nustatyti informatyviausias galvos odos sritis optimaliam nanoelektrod懦 masyvui projektuoti. Tyrime analizuoti EEG duomenys, susij臋 su regos apdorojimu, kai tiriamieji steb臈jo tris semantines vizualini懦 stimul懦 kategorijas: gyv奴nus, maist膮 ir drabu啪ius. Duomen懦 paruo拧imo metu signalai buvo filtruojami, skaidomi 寞 epochas, balansuojami pagal klases ir vertinami pagal signalo kokyb臋. Galutinei klasifikacijai atrinkti 32 tiriam懦j懦 duomen懦 rinkiniai. Vizualini懦 kategorij懦 atskyrimui taikyti atramini懦 vektori懦 ma拧inos, atsitiktinio mi拧ko, EEGNet bei CTNet modeliai. Informatyviausiems EEG kanalams nustatyti naudota atsitiktinio mi拧ko po啪ymi懦 svarbos analiz臈 ir Grad-CAM aktyvacijos 啪em臈lapiai. Geriausi膮 klasifikavimo tikslum膮 pasiek臈 atsitiktinio mi拧ko modelis 鈥� 63,2 %. Remiantis gautais rezultatais, rekomenduojamas tankesnis nanoelektrod懦 i拧d臈stymas frontocentrin臈je ir frontotemporalin臈je srityse, 寞vertinant tarpsubjektin寞 kintamum膮 kaip argument膮 individualizuotam masyvo projektavimui. Darb膮 sudaro a拧tuonios dalys: 寞vadas, literat奴ros ap啪valga, metodai ir med啪iagos, rezultatai ir j懦 aptarimas, i拧vados, literat奴ros 拧altiniai, pad臈ka ir priedai. Darbo apimtis 鈥� 54 p. teksto be pried懦, 17 iliustracij懦, 79 bibliografinai 拧altiniai. Baigiamajame darbe yra pridedami priedai.

This master's thesis examines the analysis of electroencephalography (EEG) data to identify the most informative scalp regions for the design of an optimal nanoelectrode array. The study analyses EEG data related to visual processing, recorded while participants viewed three semantic categories of visual stimuli: animals, food, and clothing. During data preparation, signals were filtered, segmented into epochs, balanced across classes, and evaluated according to signal quality. A total of 32 participant datasets were selected for final classification. Support Vector Machine, Random Forest, EEGNet, and CTNet models were applied to classify the visual categories. Random Forest feature importance analysis and Grad-CAM activation maps were used to identify the most informative EEG channels. The best classification accuracy was achieved by the Random Forest model, reaching 63.2%. Based on the results, a denser nanoelectrode arrangement is recommended in the fronto-central and fronto-temporal regions, with inter-subject variability highlighted as an argument for individualised array design. The thesis consists of eight parts: introduction, literature review, materials and methods, results and discussion, conclusions, references, acknowledgements, and appendices.The total length of the thesis is 54 pages of text excluding appendices, 17 figures, and 79 bibliographic sources. Appendices are attached separately.

Baigiamajame magistro darbe kuriamas ir tiriamas mikrobinis biokuro elementas, kuriame naudojamas biologinis komponentas yra Saccharomyces cerevisiae miel臈s. Darbe nagrin臈jama, kaip grafito elektrodo pavir拧iaus oksidacija, anglies nanovamzdeli懦 sluoksni懦 skai膷ius ir papildomas aukso nanodaleli懦 naudojimas veikia mikrobinio biokuro elemento elektrochemin寞 atsak膮, galios generavim膮 ir stabilum膮. Tyrimo metu grafito elektrod懦 pavir拧ius buvo aktyvinamas elektrochemin臈s oksidacijos metodu, o funkciniai sluoksniai formuoti u啪la拧inimo metodu. Elektrod懦 pavir拧iaus savyb臈s vertintos ciklin臈s voltamperometrijos metodu, nustatant talpin寞 atsak膮 prie拧 modifikavim膮 ir po jo. Mikrobinio biokuro elemento atsakas 寞 gliukoz臋 analizuotas pagal srov臈s tankio priklausomyb臋 nuo gliukoz臈s koncentracijos, o gauti duomenys apra拧yti Hilo lygties pagalba. Taip pat atlikti 寞tampos, galios tankio ir stabilumo matavimai, siekiant 寞vertinti sukurt懦 sistem懦 veiksmingum膮 ir efektyvum膮. Gauti rezultatai parod臈, kad elektrodo pavir拧iaus modifikavimas anglies nanovamzdeliais padidina pavir拧iaus talpin寞 atsak膮 ir sudaro palankesnes s膮lygas kr奴vio kaupimui elektrodo pavir拧iuje. Pagal bendr膮 srov臈s tankio, Hilo parametr懦 ir galios tankio analiz臋 optimali modifikacija nustatyta dviej懦 nanovamzdeli懦 sluoksniuose: 拧i sistema pasi啪ym臈jo stabiliu atsaku 寞 gliukoz臋 ir did啪iausiu galios generavimo efektyvumu. Stabilumo tyrimas parod臈, kad mikrobinio biokuro elemento i拧laik臈 funkcin寞 aktyvum膮 iki 4 savai膷i懦, ta膷iau ilgalaikiam stabilumui patikimai 寞vertinti reikalingi papildomi tyrimai. Darb膮 sudaro 6 dalys: 寞vadas, literat奴ros analiz臈, metodologija, rezultatai ir j懦 aptarimas, i拧vados, literat奴ros s膮ra拧as. Darbo apimtis 鈥� 50 psl. teksto be pried懦, 17 iliustr., 2 lent., 51 bibliografiniai 拧altiniai. Atskirai pridedami darbo priedai.

This master鈥檚 thesis focuses on the development and investigation of a microbial biofuel cell in which Saccharomyces cerevisiae yeast is used as the biological component. The study examines how graphite electrode surface oxidation, the number of carbon nanotube layers, and the additional use of gold nanoparticles in yeast affect the electrochemical response, power generation, and stability of the microbial biofuel cell. During the study, the surface of graphite electrodes was activated by electrochemical oxidation, while functional layers of carbon nanotubes were formed using the drop-casting method. To assess the effects of these modifications, the surface properties of the electrodes were evaluated by cyclic voltammetry, specifically by determining the capacitive response before and after modification. The response of the microbial biofuel cell to glucose was then analysed by examining how current density depended on glucose concentration, with the data described using the Hill equation. Voltage, power density, and stability measurements were performed to evaluate the practical efficiency of the developed microbial biofuel cell. The results showed that modifying the electrode surface with carbon nanotubes increased the electrode's capacitive response and created more favourable conditions for charge accumulation. Based on the overall analysis of current density, Hill parameters, and power density, the most favourable modification was identified as the microbial biofuel cell with two carbon nanotube layers. This system demonstrated a stable response to glucose and the highest power generation efficiency. The stability study showed that the microbial biofuel cell retained functional activity for up to four weeks; however, further studies are required to reliably evaluate long-term stability (Grammarly, 2026). The thesis consists of six parts: introduction, literature review, methodology, results and discussion, conclusions, and references. The scope of the thesis is 50 pages of text, 17 figures, 2 tables, and 51 bibliographic sources. Appendices attached separatly

Baigiamajame bakalauro darbe konstruojami Ensifer meliloti bakterijomis pagr寞sti mikrobiniai biokuro elementai, naudojant grafito ir anglies pluo拧to veltinio anodus bei dviej懦 mediatori懦 sistem膮, ir vertinama anod懦 pavir拧iaus modifikacij懦 寞taka sistemos veikimui. Literat奴ros analiz臈s dalyje ap啪velgiami mikrobini懦 biokuro element懦 veikimo principai, elektron懦 perna拧os mechanizmai, anod懦 med啪iagos ir j懦 modifikavimo b奴dai. Metodikos dalyje apra拧omas grafito ir anglies pluo拧to veltinio anod懦 paruo拧imas, j懦 modifikavimas 9,10-fenantrenchinonu bei polipirolio ir aukso nanodaleli懦 kompozitu, bakterij懦 kultivavimas, mikrobinio biokuro elemento surinkimas. Elektrod懦 pavir拧iaus morfologijai ir elektrochemin臈ms savyb臈ms 寞vertinti taikyti skenuojan膷ios elektronin臈s mikroskopijos ir ciklin臈s voltamperometrijos metodai. Mikrobinio biokuro element懦 veikimas 寞vertintas apskai膷iuojant generuojam膮 gali膮 ir galios tank寞. Rezultat懦 dalyje pateikiamas skirting懦 anod懦 bei j懦 modifikacij懦 poveikio mikrobinio biokuro element懦 veikimui vertinimas. Darb膮 sudaro 寞vadas, literat奴ros analiz臈, med啪iagos ir metodai, rezultatai, i拧vados ir literat奴ros s膮ra拧as. Darbo apimtis 44 psl.,28 iliustracijos, 2 lentel臈s, 37 bibliografiniai 拧altiniai.

In this thesis, microbial biofuel cells based on Ensifer meliloti bacteria are constructed using graphite and carbon fiber felt anodes and a dual-mediator system, and the influence of anode surface modifications on system performance is evaluated. The literature review discusses the operating principles of microbial biofuel cells, electron transfer mechanisms, anode materials, and their modification methods. The methodology section describes the preparation of graphite and carbon fiber felt anodes, their modification with 9,10-phenanthrenequinone and a polypyrrole鈥揼old nanoparticle composite, bacterial cultivation, and assembly of the microbial biofuel cells. Scanning electron microscopy and cyclic voltammetry were employed to evaluate the surface morphology and electrochemical properties of the electrodes. The performance of the microbial biofuel cells was assessed by calculating the generated power and power density. The results section presents an evaluation of the effects of different anodes and their modifications on the performance of microbial biofuel cells. The thesis consists of an introduction, literature review, materials and methods, results, conclusions, and references. It contains 44 pages, 28 illustrations, 2 tables, 37 bibliographical sources.

Baigiamojo bakalauro darbo metu buvo susintetintos modifikuotos heterociklin臈s purino baz臈s bei tirtas j懦 katabolizmas naudojant mikroorganizmus. I拧 viso buvo susintetinta penkiolika modifikuot懦 adenino ir guanino darini懦. Susintetinti junginiai charakterizuoti bei j懦 grynumas 寞rodytas taikant UV/Vis ir NMR spektroskopijos, taip pat HPLC analiz臈s metodus. Purin懦 auksotrofai buvo naudojami kaip pagrindin臈 eksperimentin臈 strategija, skirta tirti modifikuot懦 purin懦 katabolizm膮, nes j懦 augimas minimalioje terp臈je tiesiogiai priklauso nuo Escherichia coli geb臈jimo skaidyti modifikuot膮 jungin寞. Buvo naudojami E. coli kamienai, kuriuose atliktos atitinkamai purA, purH, guaA arba guaB gen懦 delecijos. Parodyta, kad i拧 vis懦 tirt懦 susintetint懦 jungini懦 E. coli gali skaidyti N6-metiladenin膮, N6-metilguanin膮, O6-metilguanin膮, taip pat tris komercinius junginius 2-chlor-6-aminopurin膮, 2-amino-6-chlorpurin膮, 6 chlorpurin膮. Kanamicino atsparumo kaset臈s pa拧alinimas i拧 螖purH kamieno nepakeit臈 auksotrofinio augimo fenotipo. Darbo strukt奴ra: 寞vadas, literat奴rin臈 dalis, metodin臈 dalis, tyrimo rezultatai bei j懦 aptarimas, i拧vados, literat奴ros s膮ra拧as, priedai. Darbo apimtis: 50 puslapiai be pried懦, 19 iliustracij懦, 6 lentel臈s, 40 bibliografiniai 拧altiniai. Priedai pridedami atskirai.

This bachelor's thesis focused on the chemical synthesis of modified heterocyclic purine bases and the investigation of their catabolism using microorganisms. A total of fifteen modified derivatives of adenine and guanine were synthesized. The identity and purity of synthesized compounds were confirmed by UV/Vis, NMR spectroscopy and HPLC analysis methods. Purine auxotrophs were used as the main experimental strategy for studying the catabolism of the modified purines, as their growth in minimal medium directly depends on the ability of Escherichia coli to catabolize the supplemented compound. E. coli strains with deletions of purA, purH, guaA and guaB genes, respectively, were used. It was shown that E. coli can catabolize N6-methyladenine, N6-methylguanine, O6-methylguanine and isoguanine out of all synthesized compounds as well as commercially available 2-chloro-6-aminopurine, 2-amino-6-chloropurine, 6-chloropurine. The removal of the kanamycin resistance cassette from the 螖purH strain did not alter the auxotrophic growth phenotype. Thesis structure: introduction, literature review, methodology, results and discussion, conclusions, references, appendices. Scope of work: 50 pages without appendices, 19 illustrations, 6 tables, 40 bibliographic sources. Appendices are attached separately.