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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

A Study on The Effect of The Warpage And Stress of PBGA Caused by The Variations of Mechanical Properties of Materials in IR-reflow Process

WANG, CHING-CHUN 20 July 2003 (has links)
The main aim of this paper is to study for the warpage and von Mises stress of PBGA package caused by the variations of mechanical properties of materials in IR-reflow process. At first, taking advantage of the package symmetry only one quarter of the package was modeled by MSC. Marc. The influence of heat transfer was considered by comparing the results of Coupled mechanical-heat transfer analysis and Mechanical analysis. In the second part, the coefficient of thermal expansions and elastic modulus of molding compound and substrate are selected as the four control factors, and the influence of the four control factors to the warpage and von Mises stress were observed. At last, emperical formulas to predicted warpage and von Mises stress values were obtained.
52

Nutritional and Microstructural Responses in Cereal Grains to Heat-Related Processing Methods

2015 October 1900 (has links)
Cereal grains share many common traits, but they also have different internal structures, nutrient values, degradation kinetics and digestion features. Heat treatments are commonly used in the feed industry. It is known that heat is able to change the nutrient values of the feed but the effect could be equivocal. In order to understand the effects of heat processing on internal structure and nutrient availability of cereal grains, two batches of wheat, triticale and corn were divided into three groups (control/raw (unheated), dry heating and moist heating) and processed at 121 °C for 80 min. Basic chemical analysis and in situ, in vitro assays were conducted and CNCPS, DVE/OEB and NRC-2001 models were used to determine the nutrient availability of the grains. In addition, two mid-IR molecular spectroscopy techniques (Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and Synchrotron Radiation Infrared Microspectroscopy (SR-IMS)) were used to gain an insight into the heat-induced changes in the functional groups. Significant (P<0.05) differences were found between the cereal grains in their nutritional availabilities, including their chemical characteristics, protein and carbohydrate fractions, energy values, the ruminal degradation kinetics, hourly effective rumen degradation ratios, potential N-to-energy synchronization, and intestinal digestion of cereal grains. Compared to dry heating, moist heating had more impact on altering the nutrient profiles and showed the potential to increase the nutrient availability of wheat and triticale for dairy cattle. Significant differences (P<0.01) were detected between different feeds and heat treatment groups by using the ATR-FTIR technique. Results were found in consistency with the conventional chemical and animal studies mentioned above despite when using the SR-IMS technique. Significant (P<0.05) correlations were detected between some structure spectral characteristics and nutrient digestion traits. In conclusion, the moist heating had more profound impact than the dry heating in increasing nutrient supplies to ruminants in wheat and triticale. The heat-induced effects found in corn were less positive. The ATR-FTIR technique could detect the internal structural changes in cereal grains, while the sensitivity and accuracy of the SR-IMS technique were not proved in this study.
53

Spectrochemical characterisation of cell transformation

Ahmadzai, Abdullah Adil January 2012 (has links)
No description available.
54

Regulation of energy balance in Caenorhabditis elegans / Reglering av energibalans i Caenorhabditis elegans

Sheng, Ming January 2015 (has links)
Obesity is a medical condition in which excess body fat has been accumulated. It is most commonly caused by imbalance between energy intake and energy expenditure (lack of physical activity and lower metabolic rate, etc.). The control of energy metabolism involves multiple tissues and signalling pathways and there is a great need for further understanding of these different interactions. In this study, I use Caenorhabditis elegans to study these complex pathways at the level of a whole organism. The downstream target of mTOR, p70 S6 kinase (S6K), has been implicated in the phosphorylation of multiple substrates and the regulation of growth and metabolism. In this study the worm homolog of S6K, rsks-1, found to be important for fat metabolism. Previous work in our lab found that RSKS-1::GFP is expressed at high levels in a set of sensory neurons and upregulated in ASJ, ASE and BAG sensory neurons in starved worms or mutants with low insulin activity. In this study, I found that the upregulation of rsks-1 expression was affected by serotonin, but not by the other neurotransmitters. Combined with the result that rsks-1 is required for the expression of TGFβ and insulin in ASI, rsks-1 may control dietary sensing by affecting insulin and TGFβ signalling within nervous system. Quantification of fat accumulation by TLC/GC revealed that in comparison to wild type worms, rsks-1 mutants have more than two-fold higher levels of triglycerides. This was confirmed by FT-IR microspectroscopy analysis. rsks-1 mutants also contain disproportionately high levels of C16:1n9 and C18:1n9 lipids compared with wild type worms. Genetic analysis has shown that rsks-1 acts either downstream of, or in parallel to the insulin and TGFβ pathways to affect fat levels. My studies showed that rsks-1 affects fat metabolism by influencing mRNA levels of genes encoding proteins in the β-oxidation pathway. Combined with defects in dietary sensing, fatty acid absorption, fertility and mitochondria function, the loss of rsks-1 activity induced much more energy storage than wild type by making a profound metabolic shift. These results are consistent with the metabolomics data analysis. Tissue specific RNAi showed that rsks-1 was required in many different tissues to regulate fat metabolism. Taken together, it can be concluded that RSKS-1 activity is needed for co-ordination of metabolic states in C. elegans. In order to understand more about the physiology behind fat accumulation, I analysed a mutant, aex-5, that has significantly lowered lipid levels. I found that this defect is associated with a significant reduction in the rate at which dietary fatty acids are taken up from the intestinal lumen. The aex-5 gene, which encodes a Kex2/subtilisin-family, Ca2+-sensitive proprotein convertase, is required for a discrete step in an ultraradian rhythmic phenomenon called the defecation motor program (DMP). Combined with other results, we conclude that aex-5 and other defecation genes may affect fat uptake by promoting the correct distribution of acidity within the intestinal lumen. This dissertation also described how to use Fourier transform infrared (FT-IR) microspectroscopy to detect lipids, proteins and carbohydrates directly in single worm. In conclusion, in this thesis I have uncovered several components that play roles in dietary sensing, fatty acid synthesis, adiposity regulation and fatty acid absorption in C. elegans.
55

The Regulation of Growth Factor Receptors EGFR and IGF-IR and the Growth Factor VEGF by Thioredoxin-1

Bair III, Warner B January 2005 (has links)
Thioredoxin-1 (Trx-1) is a redox protein that is overexpressed in many tumors where it is associated with tumor growth, inhibited apoptosis and decreased patient survival. Through redox reactions, Trx-1 is able to reduce a number of proteins including transcription factors. Sp1 activation has been implicated in the regulation of many genes involved in cellular growth and survival and its overexpression in certain cancer correlates with decreased patient survival. We demonstrate that Trx-1 is able to activate Sp1 in a redox dependent manner. Trx-1 overexpression increases Sp1 transactivation and DNA binding whereas a redox inactive Trx-1 has no effect on Sp1 DNA binding.Sp1 has been implicated in vascular endothelial growth factor regulation and we have shown that Trx-1 expression results in increased hypoxic VEGF expression and increased tumor permeability in vivo. Trx-1 overexpression results in an increase in VEGF expression that is dependent upon Sp1, as inhibition of Sp1 expression with siRNA prevented the induction of VEGF expression by Trx-1. These results suggest that Trx-1 increases VEGF expression under normoxic conditions through a redox dependent increase in the DNA binding of the Sp1 transcription factor. VEGF regulation by Sp1 could increase angiogenesis in relatively perfused areas contributing to the stimulation of tumor growth by Trx-1.We hypothesized that Trx-1 regulation of Sp1 may be part of the mechanism of Trx-1 induction of cellular growth. Sp1 regulates many genes involved in cellular growth including epidermal growth factor receptor (EGFR) and insulin-like growth factor I receptor (IGF-IR). These two growth factor receptors are important for cellular growth and have been shown to be important therapeutic targets for cancer treatment. We report that treatment with the Trx-1 inhibitor PX-12 results in decreased Sp1 DNA binding as well as decreased Sp1 activation and transactivation of VEGF, EGFR, and IGF-IR. These results indicate that Trx-1 promotes cellular growth and survival, in part, through the redox regulation of Sp1 responsive growth genes EGFR and IGF-IR. Inhibition of Trx-1, via PX-12, results in a decrease in EGFR and IGF-IR expression and suggests a new mechanism by which Trx-1 inhibition is clinically effective for treating cancer.
56

Teisės į kūno neliečiamumą ir vientisumą gynimo lyginamieji aspektai Lietuvos Respublikoje ir Jungtinėje Karalystėje / The comparative aspects of the protection of the person's right to the bodily inviolability and integrity: the republic of lithuania and the united kingdom

Andrijauskaitė, Dovilė 24 November 2010 (has links)
Šiame magistro darbe lyginamuoju metodu nagrinėjamas teisės į kūno neliečiamumą ir vientisumą gynimas skirtingos teisės sistemos valstybėse - Lietuvos Respublikoje ir Jungtinėje Karalystėje. Šiame magistro darbe siekiama atsakyti į klausimą kada ir kokiais būdais yra ginama asmens teisė į kūno neliečiamumą ir vientisumą gydymo procese. Pažymėtina, kad pagrindinis nagrinėjamos teisės gynimo būdas yra draudimas atlikti bet kokią intervenciją į žmogaus kūną be galiojančio asmens sutikimo tokioms intervencijoms. Gydytojas, kaip ir bet kuris kitas asmuo, negali gydyti ir net liesti paciento be galiojančio paciento sutikimo. Bet kokia medicininė intervencija be galiojančio paciento sutikimo yra neteisėta, nebent ją galima pateisinti tam tikromis išimtimis. Todėl daugiausia dėmesio darbe yra skiriama sutikimo medicininiams ir moksliniams tyrimams, bandymams svarbos, sutikimo elementų, išimčių iš bendrojo principo, kai sutikimas nėra reikalingas, analizei. Išskiriami tokie būtini sutikimo gydymui elementai, kaip informacijos atskleidimas, veiksnumas ir laisva valia. Kaip vienas iš asmens autonomijos įgyvendinimo aspektų analizuojama ir asmens teisė atsisakyti siūlomo gydymo. Kadangi asmens teisė į kūno neliečiamumą ir vientisumą nėra absoliuti, tai nemažas dėmesys darbe yra skiriamas aptarti situacijoms, kai asmuo gali būti gydomas ir be tokio asmens sutikimo. / The present master’s work primarily deals with the analysis of the comparative aspects of the protection of the person’s right to the bodily inviolability and integrity in different law systems – the Republic of Lithuania and the United Kingdom. Moreover, the aim of the present research is to analyse when and how the person’s right to the bodily inviolability and integrity is protected. It should be noted that the primary protection method of this right is prohibition to perform any medical intervention without the patient’s valid consent. The physician, like others, is not allowed to treat or even touch a patient without the patient’s valid consent. Any medical intervention without the patient’s valid consent is considered unlawful, unless it falls within very few exceptions. Therefore this master’s work deals mostly with analyse of the importance of consent to the medical and scientific examinations and research, the elements of the consent and the exceptions from general principal. There are three essential elements of the consent to the treatment – disclosure of the relevant information, capacity and voluntaries. As one aspect of the persons autonomy, the right to withdraw the treatment is also analyse in this master‘s work. Since the right to the bodily inviolability and integrity is not absolute one, this master’s work also deals with situations when the consent to medical interventions is not necessary and the patient could be treated without consent.
57

Chemi-code : an innovative method for wood product tracking

Smiley, Bryce Carson 05 1900 (has links)
Chain of custody in the forest sector is very dependent on effectively tracking products though the supply chain and manufacturing processes, including sawmilling, drying, planing, and pulp processes. The effectiveness of a tracking system is largely influenced by the characteristics of the process it works within, the nature of the tracking system being used, and increasingly by the penetration of technologically advanced material tracking methods into on-the-ground CoC practices. A variety of CoC systems that exist in the global marketplace accommodate the use of advanced materials tracking systems as a tool for their their implementation. These advances not only offer the potential to reinforce the traceability of products in inventory, but also promote maintenance of their certified status between the various organizations that exist along the wood product supply chain, and ultimately to the end consumer. In the past, a number of different product tracking methods have been used, all of which suffer certain shortcomings in the challenging environment of the forest industry, and the extremely complex nature of Chain of Custody tracking. This work explores the development of a novel material tracking method using the innate IR signatures of polymeric compounds, varied by compound and concentration to develop millions of potential combinations, and consequently millions of unique identities. The combined variation of multiple IR peak frequencies and magnitudes provide the conceptual basis of a chemical barcode system, named "Chemi-Code", to be explored. To prove the validity of this concept, a series of polymers were assayed for suitability in such a system by tracking their IR response stability in the presence of solar UV radiation and over time. As well, the feasibility of varying polymer concentration, and subsequently identification of concentrations by DRIFT spectroscopy was explored by constructing response curves between polymer concentration and peak absorbance, and assessing associated error. Seven polymers were identified and assessed. Only two of these polymers were found to be sufficiently stable for use in the context of the forest industry, and of those two, only one behaved in a manner that would allow peak absorbance to be used as an identifiable chemical variable. Although only one of the seven polymers was suitable for use in the "Chemi-Code" system, the study did demonstrate the validity of the concept by showing that polymers can be exploited for use in such a system.
58

Vakarų Lietuvos nuosėdinės storymės viršutinės dalies (hercininio ir alpinio struktūrinų kompleksų) 3D modelis / The 3d model of the upper part sedimentary cover of west lithuania (hercynian and alpine structural complexes)

Stankevičiūtė, Sandra 08 September 2009 (has links)
Magistrinio darbo metu buvo tiriama Vakarų Lietuvos nuosėdinės storymės viršutinės dalis, heryninio ir alpinio struktūrinio kompleksų uolienų slūgsojimas, tektoninės struktūros, tektoniniai judesių amplitudės ir laikotarpiai. Sudaryti hercyninio ir alpinio struktūrinių kompleksų stratigrafinių vienetų struktūriniai žemėlapiai (37vnt.), kurie buvo pagrindas sudarant tridimensinį (3D) modelį. Dabo tikslas - sudarytas Vakarų Lietuvos nuosėdinės storymės viršutinės dalies ( hercinio ir alpinio struktūrinių kompleksų) 3D modelis. Darbo uždavinai: • Sukurta gręžinių duomenų bazę (naudojant Exsel programą) • Sudaryti struktūriniai žemėlapiai (naudojant MapInfo programą) • Sudarytas 3D modelis ( naudojant Vertical Mapper programą). Atlikus visus darbo uždavinius padarytos tokios išvados: 1. struktūriniuose žemėlapiuose nustatytas strutūrinių vienetų uolienų slūgsojimo struktūriniai ypatumai, išskirti disjunktyviniai lūžiai (sprūdžiai), tektoninės pakilumos ir įlinkiai. 2. remiantis sudarytais struktūriniais žemėlapiais buvo išskirta nauja struktūra Telšių pakopoje – tai subplatuminės krypties (lygiagretus Telšių lūžiui) pietinis Telšių pakopos gūbrys (pakiluma), esantis netoli Telšių lūžio. 3. išskirtas Telšių prielūžinis įlinkis tarp gūbrio ir Telšių lūžio (antsprūdžio) zonoje. 4. devono sistemos svitų paplitimo ribos nustatytos sulyginus devono stratigrafinių vienetų struktūrinius žemėlapius su permo pado struktūriniu žemėlapiu. 5. nustatyti atskirų tektoninių vienetų (pakopų... [toliau žr. visą tekstą] / Reconstruction of the structure of the upper part of the sedimentary cover (Hercynian and Alpine structural complexes) of Western Lithuania and its visualization in 3D was the major aim of the master theses. The major tasks of this research were defined and fulfilled: -to collect the comprehensive depth data from wells and compile the relevant data base; -to compile a set of structural maps of the bottom of 37 different Hercynian and Alpine formations; -to visualize the set of compiled the structural maps in 3D. Data from more than 250 boreholes from the Western part of Lithuania were collected, the data base, containing numbers of depths of occurrence of 37 formations was compiled. Based on collected data, 37 structural maps were created and following, 3D visualization of set of compiled maps was carried out by the means of MapInfo and Vertical Mapper software. Detail structural and tectonic analysis of the compiled set of maps allowed to define the major structural units of the studied area, structural trends particular for each of studied formation, trends of the structural evolution of the studied territory, magnitude and timing of the major tectonic events and, the most important, to distinguish two absolutely new tectonic units – sub-latitudional Southern Elevation of the Telšiai Step and Telšiai near-fault Depression.
59

Nepilnamečių grupiniai nusikaltimai ir jų prevencijos problemos / Juvenile Gang Crimes and Problems of their Prevention

Stundžia, Gintaras 04 March 2009 (has links)
Santrauka Nepilnamečių grupiniai nusikaltimai ir jų prevencijos problemos Juvenile group crimes and difficulties of their prevention Šiame darbe aptarimas nepilnamečių nusikalstamumas kaip specifinis socialinis reiškinys, pateikiant nepilnamečių nusikalstamumo sampratą bei išskiriant specifinius bruožus, tai: asmens amžius, nepilnamečių padarytų nusikaltimų grupiškumas, didelis nepilnamečių grupinių nusikaltimų latentiškumas. Grupiškumas baudžiamosios teisės ir kriminologijos prasme reiškia, kad asmuo darydamas nusikaltimą veikia ne vienas. Todėl aptariant nepilnamečių grupinių nusikaltimų sampratą buvo remtasi bendrininkavimo institutu. Egzistuoja labai daug nepilnamečių grupių klasifikacijų, bet kriminologine prasme labiausiai domimasi neformaliomis nepilnamečių grupėmis, pradedant nuo subkultūrų (neformalių nepilnamečių judėjimų) iki visai mažų grupių bei jų susidarymo ir gyvavimo sąlygomis. Didėjant nepilnamečių nusikalstamumui didėjo ir nepilnamečių grupiniai nusikaltimai, kita vertus, pastaraisiais metai pastebima nepilnamečių nusikalstamumo mažėjimas. Tačiau neramina tai, jog daugėja nepilnamečių iki 14 m. amžiaus padariusių nusikalstamas veikas. Kalbant apie veiksnius, įtakojančius nepilnametį dalyvauti grupiniame nusikaltime, negalima išskirti pagrindinio. Manytina, visų veiksnių visuma, t. y. šeima, mokykla, bendraamžiai, žiniasklaida, sudaro prielaidas tokiam nepilnamečio elgesiui. Analizuojant nepilnamečių grupinių nusikaltimų prevenciją, būtina atkreipti dėmesį į... [toliau žr. visą tekstą] / Summary Juvenile group crimes and difficulties of their prevention Nepilnamečių grupiniai nusikaltimai ir jų prevencijos problemos This paper aims to investigate delinquency as a specific social phenomenon, providing the concept of the delinquency and identifying the specific features that are: the age of a person, group crimes committed by delinquent children, big latency of group crimes committed by the delinquent children. A group in the sense of the criminal law and criminology means that a person committing the crime is not alone. Therefore, discussion of the delinquent crime concept was based on the accessory to the crime institute. There are a lot of under-age groups’ classifications but in the criminological sense the most interesting part is nonformal under-age groups, starting from subcultures (nonformal movement of the under-age) to really small groups, there forming and existing conditions. With the rise of the delinquency the number of the delinquent group crimes was growing as well, otherwise, a reduction of the delinquency could be observed in the last few years. The problem is that the number of crimes committed by children under 14 years old is growing. Speaking about the factors that influence the under-age to participate in the group crime you cannot identify the main one. It is thought that the complex of all factors: i.e. the family, school, contemporaries, media make a precondition for such behaviour of the under-age. Analyzing the prevention of the... [to full text]
60

Atsparumą antibiotikams suteikiančių siurblių TetA ir AcrAB veiklos Escherichia coli ląstelėse tyrimas / Studies of antibiotic resistance pumps teta and acrab activity in escherichia coli cells

Švambarytė, Sandra 08 September 2009 (has links)
Šiame darbe tirta TetA ir AcrAB siurblių veikla Escherichia coli ląstelėse, panaudojant lipofilinius tetrafenilfosfonio (TPP+) jonus bei mikrobiologiniais ląstelių gyvybingumo tyrimo metodais įvertintas pasirinktų E. coli padermių jautrumas tetraciklinui. Buvo nustatyta, kad atspariausios tetraciklinui yra IQ86 ląstelės, transpozone Tn10 turinčios TetA siurblį koduojančius genus. Registruodami TPP+ pasiskirstymą tarp ląstelių ir jų inkubacinės terpės, nustatėme, kad tetraciklinas didina E. coli ląstelių išorinės membranos (IM) laidumą lipofiliniams junginiams. EDTA pagalba pralaidinus E. coli ląstelių IM, tetraciklinas lengviau patenka į ląstelę. Tai rodo, kad šis antibiotikas į ląstelę patenka ne tik per porinus, bet ir prasiskverbdamas per IM lipidinį dvisluoksnį. TPP+ jonus iš E.coli ląstelių išmetinėjantys DVA siurbliai taip pat sąveikauja ir su tetraciklinu bei chloramfenikoliu. Inkubuojant ląsteles su tetraciklinu, indukuojama šį antibiotiką išstuminėjančio TetA siurblio genų raiška. Vienok, inkubacija su tetraciklinu gali sutrikdyti kitų E. coli ląstelėse esančių DVA siurblių veiklą. Rezerpinas ir chlorpromazinas efektyviai slopina tetracikliną iš ląstelių išstuminėjančių siurblių veiklą, o fenilalanin-arginin-&#61538; naftilamidas E. coli ląstelių atveju nepasižymi DVA siurblius slopinančiu poveikiu. Nustatyta, kad DVA siurblių slopiklių poveikis stipresnis, kai jie sąveikauja su ląstelėmis terpėje be antibiotikų. / We used lipophilic tetraphenilphosphonium (TPP+) ions for functional analysis of multidrug resistance (MDR) pumps TetA and AcrAB in Escherichia coli cells. We have found that tetracycline increases the cell outer membrane permeability to lipophilic compounds. Tetracycline entered the cells faster when the bacterial outer membrane was permeabilized using EDTA. These results indicate that tetracycline enters the cell not only through the porins, but also it penetrates the lipid bilayer of the outer membrane. MDR pumps extruding TPP+ ions from E. coli cells, also interact with tetracycline and chloramphenicol. Genes of TetA pump are induced, when the cells are incubated with low concentrations of tetracycline. On the other hand, incubation of the cells with tetracycline disturbs the activity of others MDR pumps in E. coli. Reserpine and chlorpromazine effectively inhibit activity of tetracycline-extruding MDR pumps, but Phe-Arg-&#946;-naphtylamide does not show any inhibitory activity. Finally, it has been shown that action of the MDR pump inhibitors is stronger, when they are added to the bacterial suspension in the absence of antibiotics.

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