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Menstrual blood-derived stem cell paracrine factors possess stimulatory effects on chondrogenesis in vitro and diminish the degradation of articular cartilage during osteoarthritis
No full textArticular cartilage is an avascular tissue with a limited capacity for self-regeneration, leading the tissue to osteoarthritis (OA). Mesenchymal stem cells (MSCs) are promising for cartilage tissue engineering, as they are capable of differentiating into chondrocyte-like cells and secreting a number of active molecules that are important for cartilage extracellular matrix (ECM) synthesis. The aim of this study was to evaluate the potential of easily accessible menstrual blood-derived MSC (MenSC) paracrine factors in stimulating bone marrow MSC (BMMSCs) chondrogenic differentiation and to investigate their role in protecting cartilage from degradation in vitro. MenSCs and BMMSCs chondrogenic differentiation was induced using four different growth factors: TGF-β3, activin A, BMP-2, and IGF-1. The chondrogenic differentiation of BMMSCs was stimulated in co-cultures with MenSCs and cartilage explants co-cultured with MenSCs for 21 days. The chondrogenic capacity of BMMSCs was analyzed by the secretion of four growth factors and cartilage oligomeric matrix protein, as well as the release and synthesis of cartilage ECM proteins, and chondrogenic gene expression in cartilage explants. Our results suggest that MenSCs stimulate chondrogenic response in BMMSCs by secreting activin A and TGF-β3 and may have protective effects on cartilage tissue ECM by decreasing the release of GAGs, most likely through the modulation of activin A related molecular pathway. In conclusion, paracrine factors secreted by MenSCs may turn out to be a promising therapeutical approach for cartilage tissue protection and repair.iss. 9vol. 1
Analysis of Green Buildings' development in Lithuania and foreign countries
No full textBaigiamojo darbo tikslas – išnagrinėti žaliųjų pastatų plėtros tendencijas Lietuvoje ir užsienio šalyse, pateikti siūlymus žaliųjų pastatų plėtrai skatinti. Darbą sudaro įvadas, 4 pagrindinės dalys, išvados ir siūlymai, literatūros sąrašas. Įvadinėje dalyje įvardijamas temos aktualumas, nustatomi darbo tikslai ir uždaviniai. Pirmoje dalyje pateikiami įvairių autorių žaliųjų pastatų apibrėžimai, aptariamos labiausiai paplitusios sertifikavimo sistemos, nagrinėjami žaliųjų pastatų privalumai ir trūkumai. Antroje dalyje pateikiami tvarios statybos skatinimo būdai bei aptariamos Europoje taikomos žaliųjų pastatų plėtros skatinimo politinės priemonės. Trečioje dalyje pateikiami ir analizuojami žaliųjų pastatų gerosios praktikos pavyzdžiai Europos šalyse. Ketvirtoje dalyje nagrinėjama žaliųjų pastatų plėtra Lietuvoje, aptariami pavyzdžiai, taip pat analizuojami gyventojų anketinės apklausos rezultatai ir atliekama SSGG analizė. Darbo pabaigoje pateikiamos išvados ir siūlymai, literatūros sąrašas. Darbo apimtis – 79 puslapiai, 34 paveikslai, 5 lentelės, 84 bibliografiniai šaltiniai.The aim of the final work is to examine the development trends of green buildings in Lithuania and foreign countries, to present proposals for promoting the development of green buildings. The work consists of an introduction, 4 main parts, conclusions and suggestions, a list of references. In the introductory part, the relevance of the topic is named, the goals and tasks of the work are determined. The first part presents the definitions of green buildings by various authors, discusses the most common certification systems, examines the advantages and disadvantages of green buildings. The second part presents ways of promoting sustainable construction and discusses political measures for promoting the development of green buildings in Europe. The third part presents and analyzes good practice examples of green buildings in European countries. The fourth part examines the development of green buildings in Lithuania, discusses examples, as well as analyzes the results of a questionnaire survey of residents and performs a SWOT analysis. At the end of the work, conclusions and suggestions, a list of references are presented. The scope of the work - 79 pages, 34 pictures, 5 tables, 84 bibliographic sources
Biblioteka informuoja, 2023 Nr. 27 (619)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.27 (619)202
Bond behavior of stainless-steel and ordinary reinforcement bars in refractory castables under elevated temperatures
No full textRefractory castables, i.e., refractory aggregates and ultra-fine particle mixtures with calcium aluminate cement (CAC) and deflocculants, were created 40 years ago for the metallurgy and petrochemical industries. These materials demonstrate outstanding performance even over 1000 °C. Typically, they have no structural reinforcement, resisting compression stresses because of the combination of temperature and mechanical loads. This study is a part of the research project that develops high-temperature resistance composite material suitable for fire and explosion protection of building structures. However, this application is impossible without structural reinforcement, and the bond performance problem becomes essential under high temperatures. This experimental work conducts pull-out tests of austenitic stainless 304 steel bars and typical structural S500 steel bars embedded in refractory castables after high-temperature treatments. This study includes plain and ribbed bars and considers two castable materials designed with 25 wt% CAC content for 50 MPa compressive strength after drying (typical design) and 100 MPa strength (modified with 2.5 wt% microsilica). This test program includes 115 samples for pull-out tests and 88 specimens for compression. As expected, the tests demonstrated the plain bars’ inability to resist the bond stresses already at 400 °C; on the contrary, ribbed bars, even made of structural steel, could ensure a mechanical bond with cement matrix up to 1000 °C. However, only stainless steel bars formed a reliable bond with the high-performance castable, determining a promising object for high-temperature applications. Still, the scatter of the test results did not ensure a reliable bonding model. In addition, the castable strength might not be optimal to ensure maximum bond performance. Thus, the test results clarified the research objectives for further developing the reinforced composite.iss. 12vol.
Numerical analysis of two-stroke engine diffuser
No full textBaigiamajame darbe yra analizuojamos dvitakčio variklio difuzoriaus srauto charakteristikos, gautos taikant skaitinį tyrimų metodą. Taikomas skaitinis metodas yra paremtas baigtinių tūrių metodu, kuriuo pasirinkta programinė įranga „Ansys“ apskaičiuoja pasirinktos geometrijos srauto charakteristikas pritaikant skirtingas ribines sąlygas. Skaitine programine įranga buvo sukurta variklio modelio, analogiško realiam varikliui, difuzoriaus ir alkūninio veleno sąveikos simuliacija. Tokiu būdu buvo ištirtos srauto charakteristikos, kurios vėliau buvo lyginamos su modifikuotos geometrijos difuzoriaus srauto charakteristikomis. Palyginus difuzoriaus skirtingų modifikacijų srauto charakteristikas buvo galima daryti išvadas, kokia geometrijos modifikacija perneša daugiausiai srauto į variklio vidų ir didina variklio efektyvumą. Darbą sudaro 5 dalys: įvadas, literatūros analizės ir tyrimo metodų apžvalga, dvitakčio variklio difuzoriaus tyrimas, išvados ir literatūros sąrašas. Darbo apimtis – 64 p. teksto be priedų, 41 iliustracija, 3 lentelės ir 31 literatūros šaltinis.This master thesis, using numerical analysis method, examines airflow characteristics of specificic two-stroke engine. Mentioned analysis method in this thesis is based on finite volume method, which is applied by using specific software „Ansys“. By using mentioned software, characteristics of airflow are being analysed by applying different boundary conditions. Exact replica real two-stroke engine diffuser was recreated by using corresponding software. Recreated geometry was used to simulate working principle of this engine component, including its interaction with rotationary crankshaft. This way it was possible to analyze airflow characteristics of the whole process. Afterwards modifications were made to the geometry of the diffuser and same simulations were performed for each. All results and characteristics were compare between each other. After comparison conclusions were made and geometry modifications with best and worst performances were highlighted. Afterwards diffuser modification, which provided most airflow to the engine and had lowest ammound of pressure loss was concluded to be the most optimum for the work of whole two-stroke engine. Structure of thesis consists of 5 main parts: Introduction, literature analysis and overview of possible methods, two-stroke engine diffuser investigation, conclusions and references. Thesis consists of 64 p. of text without appendixes, 41 pictures, 3 tables and 31 references
Research of OpenFlow Protocol
No full text„OpenFlow“ šiuo metu yra vienintelis protokolas, galintis įgyvendinti programiškai valdomų tinklų pradininkų skelbiamas idėjas. Protokolas unikalus tuo, jog geba atskirti duomenų perdavimo įrenginio (komutatoriaus/maršrutų parinkuvo) valdymo ir duomenų perdavimo plokštumas. Visa valdymo logika perduodama dedikuotiems įrenginiams – valdikliams. Baigiamajame magistro darbe apžvelgiami ir įgyvendinami būdai, kaip pasitelkiant „OpenFlow“ protokolo savybes galima užtikrinti teikiamų duomenų perdavimo paslaugų kokybę. Darbą sudaro 5 dalys: įvadas, paslaugų kokybės valdymas duomenų perdavimo tinkluose, OpenFlow protokolo panaudojimas kokybinių parametrų valdymui, kompleksiniai kokybės valdymo uždaviniai, kokybinių parametrų valdymo metodas, išvados, literatūros sąrašas. Darbo apimtis – 52 p. teksto be priedų, 37 iliustr., 1 lent., 24 bibliografiniai šaltiniai.OpenFlow currently is the only one protocol that can implement ideas of the Software Defined Networking pioneers. The Protocol is unique because of ability to separate any network device control and data planes. All network intelligence is (logically) centralized in dedicated controllers. Objective of the master thesis is to analyze current QoS solutions provided by the protocol and propose new method that enhances QoS in data networks by using OpenFlow protocol. Master thesis contents: Introduction, Quality of Service Control in Data Networks, OpenFlow Use Cases for the Control of Quality Parameters, Integrated Problems of QoS, Method to Ensure QoS, Summary of Results. Thesis consists – 52 p. text without appendixes, 37 illustrations, 1 table, 24 references
Impact of social capital on internationalization of Lithuanian small and medium size firms
No full textBaigiamajame magistro darbe nagrinėjamas socialinio kapitalo poveikis MVĮ internacionalizacijai. Apžvelgiami internacionalizacijos ir socialinio kapitalo teoriniai aspektai, analizuojamos internacionalizacijos bei socialinio kapitalo sampratos, internacionalizaciją skatinantys ir ribojantys veiksniai, taip pat socialinio kapitalo ir internacionalizacijos sąsajos. Baigiamajamojo darbo tyrimo dalyje pateikiama tyrimų metodologija, tiriamojo reiškinio ir jo aplinkos apžvalga, atliktas ekspertinis vertinimas ir kiekybinis tyrimas, pateikiami atliktų tyrimų duomenų analizė ir rezultatai. Remiantis literatūros analize ir tyrimo duomenimis pateikiamos išvados ir pasiūlymai. Darbą sudaro šios dalys: įvadas, trys dalys (Internacionalizacijos teoriniai aspektai; Socialinio kapitalo teoriniai aspektai; Socialinio kapitalo poveikio Lietuvos mažose ir vidutinėse įmonėse tyrimas), išvados ir pasiūlymai, literatūros sąrašas, priedai.The aim of this thesis is to examine the impact of social capital on the internationalization of Lithuanian SMEs. The paper provides an overview of internationalization and social capital concepts, driving and hindering factors of SMEs internationalization, relationship of social capital and internationalization. In this thesis the research methodology, investigated phenomenon and its environment are presented, expert evaluation and a questionnaire survey of businesses are carried out. After literature analysis and research data, conclusions and suggestions are stated. Structure: introduction, three parts (Theoretical aspects of internationalization; Theoretical aspects of social capital; Investigation of Social Capital impact on Lithuanian Small and Medium Enterprises) conclusions, references, annexes
Optical response of the hybrid Tamm-surface plasmon polariton modes on the surface lattice array of gold nano-bumbs
No full textAnalysis of Body Composition Determination Techniques and Research of the Relationship between Body Composition and Physical Fitness
No full textBaigiamojo magistrinio darbo tikslas yra nustatyti ryšį tarp kūno sudėties ir fizinio pajėgumo. Išanalizuota mokslinė literatūra, kurioje aprašomi kūno kompozicijos ir fizinio pajėgumo nustatymo būdai ir priemonės bei nagrinėjami gauti rezultatai. Sudaryta kūno kompozicijos ir fizinio pajėgumo tyrimo metodika ir eiga. Tyrime dalyvavo trisdešimt žmonių (14 merginų ir 16 vaikinų). Nustatyti žmogaus kūno kompozicijai naudojami du metodai, o fiziniam pajėgumui - šeši testai. Atlikta rezultatų analizė ir įvertintas patikimumas, taikant statistinius metodus. Gautas ryšys tarp kūno kompozicijos ir fizinio pajėgumo parametrų. Pateiktos baigiamojo magistrinio darbo išvados. Darbą sudaro trys dalys: teorinė, metodologinė ir tiriamoji analitinė. Darbo apimtis – 82 p. teksto be priedų, 46 iliust., 24 lent., 85 literatūros šaltiniai. Atskirai pridedami darbo priedai.The aim of Master degree final work is to determine relationship between body composition and physical fitness. Analysis of scientific literature was made where methods, means and results of body composition and physical fitness were discussed. The measurements techniques and process of body composition and physical fitness was made. Thirty people (14 girls and 16 boys) participated in this research. To estimate body composition there were used two different methods, and for physical fitness – 6 methods. Analysis of results and reliability was made using statistical methods. Received relationship between body composition and physical fitness parameters. Conclusions of final work were made. This final work consists of three parts: theoretical, methodological and analytical research. The volume of the work is 82 pages of text without appendixes, 46 figures, 24 tables and 85 bibliographical entries. Appendixes are added separately
