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  • Open Access Lithuanian
    Authors: 
    Gabrielaitis, Dovydas;
    Publisher: Institutional Repository of Vilnius University
    Country: Lithuania

    Application of Electrochemically Synthesised Poly(Pyrrole-2-Carboxylic Acid) in Glucose Biosensor Electrochemical biosensors have high selectivity and are very sensitive to the presence of an analite. Due to the fact that the number of people suffering from diabetes (diabetes mellitus) is rising, researchers still have a high level of interest towards electrochemical glucose biosensors. Glucose oxidase (GOx) and glucose dehydrogenase are enzymes mostly used in enzyme based glucose biosensors. As GOx shows much better bioelectrocatalytic activity, stability and a low price this enzyme is being used more often. One of the main aspects for constructing a high sensitivity biosensor is using the right technique for immobilization an enzyme on the surface of the indicator electrode. For this purpose electrochemically synthesized poly(pyrrole-2-carboxylic acid) (PCPy) is used. While using the carboxyl groups on the polymer, the enzyme can be easily immobilized covalently. Various electrochemical methods can be used for the signal detection. Mostly amperometric sensors are being created. In this work, differential impulse voltammetry (DPV) is used for the registration of the analytical signal. One of the main qualities of this method is its high sensitivity. The aim of this work was to construct and analyse an electrochemical glucose biosensor using a graphite electrode modified with PCPy and covalently attached GOx enzyme (GRE/PCPy-GOx). After constructing several optimization experiments it was summarised: the synthesis of PCPy on the electrode using a steady potential synthesis of +1,0 V for 30 seconds have the highest analytical signal; the optimal pH value of the acetate-phosphate buffer solutions (A-PBS) used for the immobilisation on the enzyme is 4,0; the optimal concentration of the GOx is a 40 mg/ml; the optimal immobilization duration is 30 minutes; the optimal concentration of the electron transfer mediator K3[Fe(CN)6] in the electrochemical cell is 50 mmol/l. While using these parameters, the sensor showed quite good selectivity, analytical signal stability and repeatability if the same electrode was used. Despite this, other electrochemically active materials also have insignificant effect on the size of the analytical signal. In addition to this, the morphology of the PCPy layer on electrode surface was analysed using a scanning electron microscope (SEM). SEM images showed that chaotically located PCPy clusters (1 – 5 µm in diameter) consisting of globular particles of 100 – 200 nm in diameter were formed during the synthesis.

  • Publication . Bachelor thesis . 2020
    Open Access Lithuanian
    Authors: 
    Vaišys, Laurynas;
    Publisher: Institutional Repository of Vilnius University
    Country: Lithuania

    In this study methods of automatic pneumonia detection in chest X-rays (CXR) that are found in literature are presented. These methods are based on traditional image processing techniques and convolutional neural networks. One of presented is the method proposed by A. Sharma and his colleagues. It is based on traditional image processing and Otsu thresholding. We proposed new algorithm that was based on A. Sharma’s one. In this algorithm we used HOG, Haar-like and LPB approaches to detect and cut lungs from whole image as well as Otsu thresholding. By this algorithm we created application. While testing it with real CXRs we noticed that this method could help recognize pneumonia, because for healthy lungs it showed less corrosion in lung masks and they were smoother than for lungs with present pneumonia. However, sometimes it was not able to correctly recognize lungs and cut CXRs with present pneumonia. Also, sometimes even in healthy lungs Otsu thresholding was showing some disintegration that are common for pneumonia affected lungs.

  • Open Access Lithuanian
    Authors: 
    Šedienė, Severina;
    Publisher: Institutional Repository of Lithuanian University of Health Sciences
    Country: Lithuania

    Practical values of research Positron emission tomography with computer tomography is a very important tool for head and neck squamous cell staging, treatment response and treatment planning. We hope that after our trial 18F-FDG PET/CT will be validated for interim treatment, after induction chemotherapy, and evaluation. Research aim The aim of this thesis is to evaluate efficacy of semi-quantitative PET/CT parameters (SUVmax, SUVav, SUVpeak, MTV and TLG) for treatment response evaluation and prognostic or predictive values. Research objectives 1. To assess and compare the potential of metabolic parameters to predict the response to treatment before the planned induction chemotherapy, by calculating the 2-year disease free survival (DFS) and overall survival (OS); 2. To assess and compare the potential of the chosen threshold values of metabolic parameters to predicte the response to treatment before the planned induction chemotherapy, by calculating the 2-year disease free survival and overall survival; 3. To assess and compare the potential of the chosen threshold values of metabolic parameters delta values to predicte the response to treatment by calculating the 2-year disease free survival and overall survival; 4. To assess and compare the potential of metabolic parameters to predict the response to treatment following induction chemotherapy, by calcu-lating the 2-year disease free survival and overall survival; 5. To assess and compare the potential of the chosen threshold values of metabolic parameters to predict the response to treatment following the planned induction chemotherapy, by calculating the 2-year disease free survival and overall survival

  • Open Access Lithuanian
    Authors: 
    Gintaras Turkevičius; Vytautas Sirvydis; Arimantas Grebelis; Rasa Joana Čypienė; Palmyra Semėnienė; Vilija Jakumaitė; Gediminas Kitra; Gediminas Kundrotas; Pranas Šerpytis;
    Country: Lithuania

    Gintaras Turkevicius 1 , Vytautas Sirvydis 1 , Arimantas Grebelis 1 , Rasa Cypienė 1 , Palmyra Semėnienė 1 , Vilija Jakumaitė 2 , Gediminas Kitra 2 , Gediminas Kundrotas 2 , Pranas Serpytis 3 1 Vilniaus universiteto Sirdies ir kraujagyslių ligų klinikos Sirdies chirurgijos centras, Santariskių g. 2, LT-08661 Vilnius El. pastas: chirurgai@santa.lt 2 Klaipėdos jūrininkų ligoninė 3 Vilniaus universiteto Kardiologijos ir angiologijos centras Darbo tikslas: Isanalizuoti ligonių, sergancių ūmine kylanciosios aortos disekacija, chirurginio gydymo rezultatus. Ligoniai ir metodai: 1997–2007 metais operuoti 89 ligoniai, sergantys ūmine aortos disekacija. Isanalizuota ligonių priesoperacinė būklė, pasirinktas sirdies operacijos metodas, ankstyvieji ir vėlyvieji gydymo rezultatai. Rezultatai: Pooperaciniu laikotarpiu mirė 26 ligoniai (29,2 %). Mirties priežastys: nesustabdomas pooperacinis kraujavimas – 11, sirdies nepakankamumas – 5, galvos smegenų pažeidimas – 8 ir dauginis organų nepakankamumas – 2 ligoniams. Labiausiai kraujavo operuojant Bental de Bono metodika. Priesoperaciniu laikotarpiu 23 ligoniams (25,8 %) diagnozuota sirdies tamponada ir akivaizdus sirdies nepakankamumas. Is sių ligonių 19 (82,6 %) teko atlikti retorakotomiją dėl kraujavimo ir 6 (26,0 %) gydyti sunkų inkstų funkcijos nepakankamumą. Vėlyvuoju laikotarpiu is isgyvenusių 63 ligonių du mirė nepraėjus 12 mėnesių, 5 – praėjus 1–6 metams po operacijos. Isvados: Kylanciosios aortos disekacijos operacinio gydymo rezultatai priklauso nuo ligonių būklės pries operaciją ir operacijos pobūdžio. Sirdies tamponada pries operaciją ir didelio laipsnio sirdies nepakankamumas labai didina operacijos riziką. Vėlyvieji chirurginio gydymo rezultatai yra geri. Reiksminiai žodžiai: kylancioji aorta, disekacija, chirurgija Acute dissection of ascending aorta: data of surgical treatment Gintaras Turkevicius 1 , Vytautas Sirvydis 1 , Arimantas Grebelis 1 , Rasa Cypienė 1 , Palmyra Semėnienė 1 , Vilija Jakumaitė 2 , Gediminas Kitra 2 , Gediminas Kundrotas 2 , Pranas Serpytis 3 1 Vilnius University, Clinic of Cardiovascular Diseases, Heart Surgery Centre, Vilnius University Hospital Santariskių Clinics, Santariskių str. 2, LT-08661 Vilnius, Lithuania E-mail: chirurgai@santa.lt 2 Klaipėda Seamen’s Hospital 3 Vilnius University, Cardiology and Angiology Centre Objective: The aim of present study was to analyze the results of surgical treatment of patients suffering from dissecation of the ascending aorta. Patients and methods: During the period 1997–2007, 89 patients underwent operations because of acute dissecation of aorta. The preoperative data, methods of surgery and short-term as well as long-term results of treatment were analyzed. Results: There were 26 postoperative deaths (29.2 %). The causes of death included fatal postoperative bleeding (11), heart failure (5), brain impairment (8), multiple organ insufficiency (2). Bleeding was mostly characteristic of Bental-De Bono operations. In 23 patients (25.8 %), heart tamponade and marked heart failure were diagnosed preoperatively. In 19 of these patients (86.2 %), a rethoracotomy was required because of bleeding, and 6 (26.2 %), suffered from marked renal insufficiency. Seven of 63 survivors died during the long-term observation period (the survival time in two patients was up to 1 year, and 5 patients survived 1–6 years after the operation). Conclusion: The results of surgery for ascending aorta dissection depend on the preoperative condition of the patients and the mode of operation. The preoperative cardiac tamponade with a marked heart failure increases the risk of operation. The long-term results of the treatment are excellent. Key words: ascending aorta, dissection, surgery.

  • Open Access Lithuanian
    Authors: 
    Sidabraitė, Vaida;
    Publisher: Lithuanian Academic Libraries Network (LABT)
    Country: Lithuania

    Magistro baigiamajame darbe tiriama Jungtinių Tautų Saugumo Tarybos veikla 2003–2013 m., siekiant įvertinti institucijos efektyvumą palaikant tarptautinę taiką ir saugumą. Darbą sudaro keturi skyriai. Pirmajame skyriuje aptariami instituciniai Saugumo Tarybos požymiai, Jungtinių Tautų Chartijoje nustatyti įgaliojimai ir pagrindiniai veiklos po Šaltojo karo bruožai. Antrajame skyriuje, remiantis išsamia surengtų posėdžių ir priimtų sprendimų analize, nagrinėjama Saugumo Tarybos veikla 2003–2013 m. Trečiajame skyriuje analizuojama pastebėtų veiklos tendencijų ir sprendimų priėmimo proceso įtaka Saugumo Tarybos efektyvumui. Atsižvelgiant į vykstančias diskusijas dėl Saugumo Tarybos reformos, pristatomi pagrindiniai reformos aspektai siekiant stiprinti efektyvumą. Ketvirtasis skyrius yra skirtas apžvelgti Lietuvos santykį su Saugumo Taryba, atkreipiant dėmesį į Saugumo Tarybos veiklą Lietuvos pirmininkavimo 2014 m. vasario mėnesį metu ir Lietuvos poziciją dėl Saugumo Tarybos reformos. This Master Thesis examines the activity of the United Nations Security Council during the period of 2003–2013, in order to assess the effectiveness of the institution in maintaining international peace and security. The paper consists of four chapters. The first chapter presents the institutional character of the Security Council, its powers established by the United Nations Charter and the key features of post-Cold War activity. Based on the extensive analysis of the meetings held and decisions taken, the second part of this paper examines the activity of the Security Council during the period of 2003–2013. The third chapter assesses the effectiveness of the Security Council based on the observed trends of actions and the decision making processes. In light of the ongoing discussions on the reform of the Security Council, the main aspects of the reform are presented, taking into account the stated aim of strengthening the effectiveness. The fourth chapter is devoted to an overview of Lithuania’s relationship with the Security Council, with the focus on the activity of the Security Council during the Lithuanian Presidency in February 2014 as well as the official position of Lithuania on the Security Council reform.

  • Open Access Lithuanian
    Authors: 
    Truncaitė, Anna; Paulavičius, Sigitas;
    Publisher: Kaunas University of Technology
    Country: Lithuania

    In order for maintenance or migration of a legacy system to be efficient and safe, complete documentation is required, which might be non-existent, lost or out-dated. Recovery of this information from legacy system itself is possible through the proceses of reverse engineering. This work is concerned with reverse data engineering to recover of complete logical schema by first extracting explicitly declared database structure and constraints and then completing it by extarcting implicit constructs and constraints from source code and data analysis. The methology described in this work is sought to be simple to use and oriented mainly towards data migration efforts, which was found to be the field where reverse data engineering is used the most. The methodology is concerned with extraction of complete logical schema, although it is not always required for data migration proccess in its full extent. An issue of discovery and separation of joined entities is adressed in this work. Joined entity can be defined as multiple conceptual entities that were joined into single database table due to certain external limitations on number of entities. This situation is not rare in legacy systems especially and is not found to be adressed by any other method of database reverse engineering. Magistro darbe pateikta atvirkštinės duomenų inžinerijos (ADI) analizė. Remiantis analizės rezultatais sudaryta ADI metodika, kuri yra lengvai pritaikoma praktikoje ir skirta išsamios loginės schemos atstatymui. Taip pat aprašyta sudarytos ADI metodikos aplinka ir vartotojai. Pateiktas ADI įrankio prototipo projektas, kuris skirtas metodikos veiksmingumo eksperimentiniam tyrimui atlikti. Aprašyta ADI įrankio prototipo realizacija ir pateiktas eksperimentinis metodikos tyrimas. Tai pat pateiktas sudarytos ADI metodikos įvertinimas lyginant metodiką su kitais metodais ir kokybinis įvertinimas apklausiant ekspertus.

  • Open Access Lithuanian
    Authors: 
    Dumbliauskas, Vytautas;
    Publisher: Institutional Repository of Vilnius University
    Country: Lithuania

    Magistro darbo tikslas – ištirti Sovietų Lietuvos ekonominio savarankiškumo idėjų raidą 1988-1989 metais. Darbo tikslui pasiekti buvo sprendžiami šie uždaviniai: 1.Atskleisti XX a. 9 dešimtmečio pabaigoje vykusias diskusijas dėl Lietuvos kaip Sovietų Sąjungos išlaikytinės statuso. 2.Pristatyti Lietuvos ekonominio savarankiškumo koncepciją ir išanalizuoti jos įgyvendinimą.3.Išnagrinėti savų pinigų idėjas bei pristatyti Lietuvos pinigų ir kredito sistemos koncepciją. Atliekant tyrimą bei atsakant į išsikeltus klausimus, prieita prie šių išvadų: 1.Lietuvos ūkis per visą sovietinės okupacijos laikotarpį buvo nuosekliai integruotas į Sovietų Sąjungos ūkį. Centralizuota ūkio valdymo – planavimo, aprūpinimo materialiniais ištekliais, produkcijos realizavimo, bankų ir finansų – sistema jokio savarankiškumo atskiriems SSRS regionams neleido, todėl ir Lietuvoje ūkinis gyvenimas buvo iš esmės toks pats kaip ir visoje Sovietų Sąjungoje. 2.„Perestroikos“ autorių pabrėžiama ūkiskaitos sąvoka leido Lietuvos ekonomistams kalbėti ne tik apie įmonės, bet ir apie visos respublikos ūkiskaitą. Susikūrus Lietuvos persitvarkymo sąjūdžiui, buvo pradėta naudoti ir respublikos ekonominio savarankiškumo sąvoka, kuria buvo nusakomi kokybiškai kitokie santykiai su centrine sovietų valdžia. 3.Diskusijose apie respublikos ūkiskaitą ir ekonominį savarankiškumą mūsų ekonomistai argumentuotai paneigė centrinės sovietų valdžios teiginius, kad Lietuvos išlaidos viršija jos pajamas, t.y. kad Lietuva yra Sovietų... [toliau žr. visą tekstą] I have chosen the subject “Ideas of Economic Independence in Soviet Lithuania in 1988-1989”, because it is not widely investigated in Lithuanian historiography. Lithuanian Soviet Socialist Republic was established after Soviet Occupation of Lithuania in 1940 and existed to 1990. The Lithuanian SSR was renamed the Republic of Lithuania again on March 11, 1990, all legal ties of sovereignty were cut with the Soviet Union as Lithuania declared the restitution of its independence. But its way to independence was long and not easy. The last five years of occupation beginning in 1985, when Mikhail Gorbachev made significant changes in the economy were perestroika and glasnost. His policy of glasnost gave some freedom for media and hope for occupied nations. The objective of master thesis is to investigate process and development of ideas of economic independence in Soviet Lithuania (1988-1989). To obtain the objective I made three tasks: 1) to review Soviet Lithuanian economy in the end on 1980s and to show discussions about Lithuanian SSR as dependant republic of Soviet Union; 2) to introduce “Lithuania’s economic independence conception” and to analyze its implementation; 3) to review ideas about its own currency and to introduce Lithuania’s system of money and credit conception. In the end I came to these conclusions: 1) Soviet Lithuania’s economy was integrated to Soviet Union’s central economy and there was no self-sufficiency for Soviet republics; 2) in the discussions about... [to full text]

  • Open Access Lithuanian
    Authors: 
    Barsytė, Goda;
    Publisher: Kaunas University of Technology
    Country: Lithuania

    The aim - to perform Lithuanian University of Health Sciences Kaunas klinikos hospital waste management system analysis and propose methods that will enable to reduce the quantities of medical waste and increase the efficiency of their management. Following an analysis of the literature has identified the main infected waste treatment methods: burning, processing and microwave digestion. Also, many of the world's hospital pays great attention to food waste reduction. Most acceptable methods of their decline is the acquisition of composting, sorting. However, Lithuania does not pay close attention to trends in sustainable waste management system in health care facilities. In order not allocated to finance not created the legal framework. After analysis of literature, Kaunas Hospital Waste Management System has been used in this analysis methodology: cleaner production, material flow analysis, environmental management cost assessment, as well, based on sustainable development principles. Lithuanian University of Health Sciences Kaunas Clinics Hospital Waste Management sustainability analysis designed to assess the indicator system covering social, economic and environmental aspects. It was found that the high costs allocated to utilities payment (4.606.418,85 €). The main causing factors: inadequate waste streams maintenance and management of municipal waste is not sorted, the workers are not encouraged and motivated. Applying the basic principles of waste management were offered food waste composting hospital area - a municipal waste stream could be reduced by 90%, infected waste management buy-processing technology, which reduces the amount of waste by 80% and reduces management costs 5 times. Darbo tikslas - atlikti Lietuvos sveikatos mokslų universiteto ligoninės Kauno klinikos atliekų tvarkymo sistemos analizę ir pasiūlyti metodus, leisiančius mažinti medicininių atliekų kiekius ir efektyvinti jų tvarkymą. Atlikus literatūros analizę buvo nustatyti pagrindiniai infekuotų atliekų apdorojimo būdai: deginimas, apdorojimas mikrobangomis ir autoklavavimas. Taip pat, daugelis pasaulio ligoninių didelį dėmesį skiria maisto atliekų mažinimui. Priimtiniausi būdai jų mažėjimui yra kompostavimo sistemos įsigijimas, rūšiavimas. Tačiau Lietuvoje nėra tendencijos skirti didelį dėmesį darniai atliekų tvarkymo sistemai sveikatos priežiūros įstaigose. Tam nėra skiriama finansų, nėra sukurtos įstatyminės bazės. Atlikus literatūros analizę, Kauno klinikų atliekų tvarkymo sistemos analizei buvo naudotos šios metodikos: švaresnės gamybos, medžiagų srautų analizės, aplinkos vadybos kaštų vertinimo, taip pat, remtasi darnios plėtros principais. Lietuvos sveikatos mokslų universiteto ligoninės Kauno klinikos atliekų tvarkymo darnumo analizei vertinti sukurta indikatorių sistema, apimanti socialinius, ekonominius ir aplinkosauginius aspektus. Nustatyta, jog dideli kaštai skiriami komunalinių paslaugų apmokėjimui (4.606.418,85 €). Pagrindiniai veiksniai tai lemiantys: nepakankama atliekų srautų priežiūra ir valdymas, komunalinės atliekos nerūšiuojamos, darbuotojai nėra skatinami ir motyvuojami. Pritaikius atliekų tvarkymo pagrindinius principus buvo pasiūlyta maisto atliekas kompostuoti ligoninės teritorijoje – tai komunalinių atliekų srautą galima būtų sumažinti 90%, infekuotų atliekų tvarkymui įsigyti apdorojimo technologiją, kuri atliekų kiekį sumažina 80%, o tvarkymo kaštai sumažėja 5 kartus.

  • Open Access Lithuanian
    Authors: 
    Tomas Kaulius; Arvydas Ramonas;
    Country: Lithuania

    Straipsnyje analizuojama žmogiškojo asmens struktūra Edith Stein filosofijoje. Pristatomos mąstytojos personalistinio ir antropologinio mąstymo įžvalgos. Akcentuojama fenomenologinio metodo reikšmė, apibrėžiant žmogiškąjį asmenį (apimant klasikinę jo struktūrą: kūną, sielą ir dvasią). Gilinamasi, ar, taikant šį metodą, asmens struktūra yra atpažįstama. Analizuojama, kokiu būdu prasmingai išgyvenama žmogiškoji patirtis apie žmogiškąjį asmenį. Edith Stein’s theoretical overview of the human person presented in the article contributes to better understanding of the meaning of phenomenological analysis. The said analysis is carried out by thorough exploration of the subject’s mental reality and soul, i.e. an individual is examined with the aim of bringing out the structure of the human person in the context of the world experienced by him. The structure is presented in compliance with ethical and religious reasoning. The article defines phenomenological analysis as a search for individual’s basic nature through his intersubjective relations. Specific relation, named empatia in Edith Stein’s works, confirms the fundamental correlation of person-I and person-Other. From Stein’s point of view, humans are inevitably connected through a personal-emotional network, primarily ethical and spiritual, due to which each person has a motivated responsibility for another person. That helps to understand the structure of the human person as a three-dimensional construction: the body (corpo), the soul (psyche), and the spirit (spirito). This approach allows understanding better individual’s irreducible value, dignity, and originality, and enables one seeing that one’s personal activity is intentionally directed towards “another person” and the community. Therefore, Edith Stein’s philosophy is undoubtedly significant primarily due to the elevation of the value and significance of the human person.

  • Publication . Master thesis . 2014
    Open Access Lithuanian
    Authors: 
    Kapusto, Rimas;
    Publisher: Lithuanian Academic Libraries Network (LABT)
    Country: Lithuania

    Ištirti mažos galios horizontaliosios ašies vėjo jėgainės energetines charakteristikas ir nustatyti efektyvumo didinimo galimybes. Survey energy characteristics of little capacity horizontal axis wind power plant and identify efficiency increase potential.

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