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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.
181

Low-Scaling Local and Fragment Self-Consistent Field Potentials in Molecular Systems

Werner, Martin 24 November 2017 (has links)
No description available.
182

Parasitas intestinais de Lontra Longicaudis (Olfers, 1818) (Carnivora, Mustelidae) em riacho e lagoa do Distrito de Sousas/Campinas-SP / Studys of intestinal parasite in Lontra Longicaudis (Carnivora, Mustelidae) (Olfers, 1818) in a creek an pond of Sousas District, Campinas, São Paulo, Brazil

Alarcon, Diego Fernandes 31 October 2006 (has links)
Orientador: Marlene Tiduko Ueta / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T00:02:43Z (GMT). No. of bitstreams: 1 Alarcon_DiegoFernandes_M.pdf: 8141836 bytes, checksum: 830e38e5f19d73153a16ed4df89c73bc (MD5) Previous issue date: 2006 / Resumo: Os helmintos intestinais de Lontra longicaudis (CARNIVORA, MUSTELIDAE) foram estudados, com os materiais fecais recolhidos de um pequeno riacho (Riacho Ribeirão Cachoeira) localizado em um fragmento florestal de Mata Atlântica, e de uma lagoa localizada no condomínio Notredame, ambos situados no município de Campinas, mais precisamente no distrito de Sousas. O objetivo foi relacionar, pelo levantamento de parasitas intestinais, aspectos tróficos e comportamentais de L. longicaudis à aquisição de parasitas. Em laboratório, o material fecal de cada local foi processado e analisado individualmente, utilizando-se os métodos qualitativos rotineiros de exame de fezes: sedimentação espontânea (HOFFMAN et al,. 1934) e Willis (WILLIS, 1921). Das 39 amostras coletadas em Ribeirão Cachoeira, 22 apresentaram resultados positivos para ovos e/ou larvas de helmintos (56,4%). Na lagoa do Notredame foram coletadas 29 amostras fecais, das quais 13 apresentaram resultados positivos para ovos ou larvas de helmintos (44,8%). Foram observados sete tipos morfológicos de ovos de helmintos e dois tipos de larvas de nematódeos. Dentre os ovos, os mais prevalentes, tanto no riacho (54,5% trematódeo; 22,7% Strongyloides) quanto na lagoa (46,2% trematódeo; 46,2% Strongyloides), foram o de um trematódeo e ovo de Strongyloides sp. Um dos tipos de larva encontrada foi o de Strongyloides sp, que foi a mais prevalente (54,5% riacho e 15,4% lagoa). Trata-se do primeiro registro de Strongyloides sp em lontras neotropicais / Abstract: The intestinal helminthes of the otter Lontra longicaudis (CARNIVORA, MUSTELIDAE) were studied. The fecal samples were collected in a creek (Ribeirão Cachoeira) situated in a forest fragment of Atlantic forest, and in a pond located in the Notredame house complex, both in the municipality of Campinas, Sousas district, São Paulo state, Brazil. The aim of the present study was to associate, through the intestinal parasites survey, trophic and behavioral aspects of L. longicaudis with the acquisition of parasites. The Faecal samples from each place was processed and analyzed individually, using the qualitative routine faecal methods: spontaneous sedimentation (HOFFMAN et al,. 1934) and Willis (WILLIS, 1921). From total 39 samples collected in Ribeirão Cachoeira creek, 22 were positive for eggs and /or larvae of helminthes (56,4%). In the Notredame house complex pond, samples from 29 total faecal samples collected, 13 showed positive results for eggs and /or larvae of helminthes (44,8%). Seven morphological types of helminthes eggs and two types of Nematode larvae were observed. Among the eggs, the most prevalent in the creek (54,5% trematode; 22,7% Strongyloides) and in the pond (46,2% trematode; 46,2% Strongyloides) were trematode egg and Strongyloides sp. egg. One of larvae found was of Strongyloides sp, type which was the most prevalent one (54,5% creek and 15,4% pond). This is the first occurrence of Strongyloides sp in neotropical otters / Mestrado / Mestre em Parasitologia
183

Zona de amortecimento do parque estadual da Serra do Mar Núcleo Santa Virgínia: subsídios ao manejo sustentável dos fragmentos de mata atlântica

João Paulo Villani 12 April 2007 (has links)
O objetivo deste trabalho é coletar informações pertinentes ao manejo e práticas rurais desenvolvidas nas propriedades situadas no entorno do Parque Estadual da Serra do Mar - Núcleo Santa Virgínia. O trabalho tem como principio subsidiar a construção de uma proposta de manejo sustentável a ser desenvolvida na Zona de Amortecimento, envolvendo a participação da comunidade rural das bacias hidrográficas do Rio Paraibuna e Ribeirão da Cachoeirinha. A proposta deverá promover a sustentabilidade das atividades do entorno e a garantia e manutenção da diversidade biológica e dos recursos genéticos da unidade de conservação. A proposta focaliza o enriquecimento dos remanescentes florestais com o plantio do palmito Juçara (Euterpe edulis Mart.), como alternativa de renda para o produtor rural. Os procedimentos metodológicos para a caracterização geral da área e da comunidade envolvida foram os levantamentos de campo, fontes documentais e de entrevistas. A definição dos critérios para delimitação da zona de amortecimento e seleção dos fragmentos baseou-se no limite da bacia hidrográfica e na legislação ambiental vigente. Utilizou-se para o mapeamento e identificação dos fragmentos, o Sistema de Informação Geográfica (SIG) Arc (GIS) 8.1.2 - ESRI. Os resultados apontaram 20 fragmentos da zona de amortecimento com potencialidades para a implantação do manejo. Indicaram ainda, a necessidade de articulação dos setores da região e a adoção de estratégias que incentivem a capacitação dos técnicos da CATI e proprietários rurais. / The purpose of this project is to suggest a sustainable management of forest fragment situated in Parque Estadual da Serra do Mar Núcleo Santa Virgínia buffer zone. Considered as basic principle: the Paraibuna river basis rural community involvement, the surrounding activities will become sustainable and the guarantee and maintenance of biological diversity and the genetics resources from a protect area. The forest remainder will improve with the Juçara (Euterpe edulis Mart) palm cultivates, which, will be an alternative for the land owners. The methodology for characterization the area and the community was land visiting, documents source and interviews. The buffer zone boundary and the fragments select have been done according to the environmental law and the hydrographical basin. The use of the SIG Arc (GIS) 8.1.2 ESRI, was important for the forest fragment identification. The results 20 fragments with capacity to implementation the management inside the buffer zone, and shows that is necessary to promote the relationship between region sector and adopts strategies which capacity the CATI technician and land owners.
184

Holographic Hieroglyph / Holographic Hieroglyph

Sobotková, Adéla Unknown Date (has links)
Topics fragmentary , symbolism and memory are the basic elements of creation and thinking Adele Sobotková (1987 ) . In her installation made of clay and covered with a udusaných objects together with the soil can walk, touch , read, intervene . This raises a cryptographic magical space full of mysterious objects in the video that represent clusters of personal hieroglyphic symbols and structures without the possibility of accurate decryption. These enigmatic characters are like glass or water , are changing , floating landscapes and refer to feelings of uncertainty, and forgetting the past, which is not entirely clear - is revealed as a mirage . Hologram is a representation of reality or reality that no longer exists but in time, or never existed , dream hi - technology , the current symbol of immortality, infinite and preservation in time. " Holographic hieroglyph " is a fluid phenomenon with varying meanings depending on its reading , the transcript or constant metaphor memories and the zpřítomňování hand in hand zpřítomňování a revival oblivion . Unclear character that has certainly not decipher , and yet we have it all in front of him , we see him from all sides , but also through him is the present and yet unreal . Great recording of uncertainty. (press release of the exhibition Holographic Hieroglyph in the Youth Gallery in Brno)
185

Study of fission of exotic actinides by relativistic reactions / Étude de la fission d'actinides exotiques par réaction relativiste

Yan, Yiman 28 September 2016 (has links)
SOFIA (Studies On FIssion with Aladin) est un programme expérimental innovant qui a pour objectif la mesure de plusieurs observables de la fission nucléaire : les taux de production isotopiques des fragments de fission, l'énergie cinétique totale des fragments, et la multiplicité des neutrons prompts. Ces informations sont obtenues pour une large variété d'actinides et de pré-actinides. Le recours à la cinématique inverse (le système fissionnant est le faisceau et non pas la cible) est le seul moyen d'identifier les fragments à la fois en charge et en masse. Le travail de doctorat présenté dans cette thèse porte sur l'expérience menée en Octobre 2014 et dédiée à la mesure de la fission de ² ³ ⁶ U induite par excitation coulombienne, soit l'analogue de la fission de ² ³⁵U induite par neutron.Les expériences SOFIA ont lieu à GSI (Darmstadt, Allemagne), la seule installation au monde capable de délivrer un faisceau d'uranium ² ³⁸ de 1 GeV par nucléon. Ce faisceau primaire subit une première fragmentation, dont les produits sont sélectionnés par le FRS (FRagment Separator) afin de former un faisceau secondaire du noyau d'intérêt, en l'occurrence ² ³ ⁶ U, qui est guidé vers l'expérience SOFIA où sa fission est déclenchée.Certains noyaux proches de ² ³ ⁶ U sont également transmis par le FRS : il est donc nécessaire de procéder à l'identification en masse et en charge du système fissionnant, puis d'identifier les deux fragments de fission. Dans les deux cas, l'identification, réalisée événement par événement, repose sur la mesure simultanée de la perte d'énergie dans un gaz, de la rigidité magnétique et du temps de vol. Seules les fissions induites par excitation coulombiennes sont pertinentes : la contribution des réactions nucléaires à la production des fragments doit donc être mesurée et soustraite.L'analyse présentée dans ce document inclut l'identification du faisceau secondaire en masse et en charge, l'identification en charge des fragments de fission, l'estimation de la contribution des réactions nucléaires, et finalement les taux de production des éléments obtenus dans la fission de ² ³ ⁶ U. Ces résultats sont comparés à ceux d'autres mesures réalisées sur SOFIA, et à des résultats antérieurs obtenus par d'autres techniques. / SOFIA (Studies On FIssion with Aladin) is an innovative experimental program which aims to measure several fission observables — the isotopic fission yields, the total kinetic energy of the fragments and the prompt neutron multiplicity, for a wide range of actinides and pre-actinides. The use of inverse kinematics (the fissioning system is the beam instead of the target) is the only way to fully identify fragments in charge and mass. The PhD work presented in this thesis concerns the experiment conducted in October 2014, and is focused on the Coulomb-induced fission of ² ³ ⁶ U, which can be regarded as the analog of the neutron-induced fission of ² ³⁵U.The SOFIA experiments take place in GSI (Darmstadt, Germany) because it is the sole facility in the world which delivers a beam of ² ³⁸U at 1 AGeV. This beam is fragmented and the products are selected by the FRS (FRagment separator) in order to deliver a secondary beam of nuclei of interest - ² ³ ⁶ U in our case, which is then guided to the SOFIA setup where its fission is triggered.Since some nuclides with close atomic and mass numbers to ² ³ ⁶ U are also transmitted by the FRS, it is necessary to identify the fissioning system from the secondary beam first, and then identify both the associated fission fragments. All identifications are performed event by event on the basis of measurements of the energy loss, the magnetic rigidity and the time of flight. Since we are only interested in the Coulomb-induced fission of ² ³ ⁶ U, the contribution of fragmentation fissions on the nuclear charge distribution of fission fragments has to be suppressed.The analysis in this paper involves the isotopic identification of the fissioning system, the nuclear charge identification of the fission fragments, the estimation of the nuclear contribution, and the extraction of the elemental fission yield. The results are then compared to other measurements performed with the SOFIA setup, as well as previous results obtained by other techniques.
186

Méthodes RMN pour la découverte de nouveaux ligands ciblant les récepteurs couplés aux protéines G / NMR methods for G-protein coupled receptors drug discovery

Raingeval, Claire 23 October 2019 (has links)
Les récepteurs couplés aux protéines G (RCPGs), constituent la plus grande famille de protéines membranaires dans le génome humain. Les RCPGs sont des protéines de signalisation, qui exercent leur action à la surface des cellules, en réponse à une grande variété de stimuli extérieurs. Ils jouent un rôle primordial dans de nombreuses fonctions physiologiques et sont donc impliqués dans une multitude de pathologies comme les maladies cardiovasculaires, métaboliques, neurodégénératives, psychiatriques et oncologiques. L'attribution du prix Nobel de chimie 2012 aux professeurs Robert Lefkowitz et Brian Kobilka pour leurs travaux et avancées spectaculaires dans le champ de recherches des RCPGs, souligne encore leur importance. Les RCPGs constituent également la plus importante cible thérapeutique, avec 30% des médicaments actuellement disponibles sur le marché qui exercent leur action via un RCPG. Cependant, la découverte de nouveaux ligands reste un chalenge. Le but est de développer des approches basées sur la RMN à l’état liquide, qui auront un impact positif sur la recherche de ligand de RCPGs, grâce à l’étude et la caractérisation de récepteur pleine taille, solubilisés en micelles de détergents ou enchâssés en bicouches lipidiques natives / G protein-coupled receptors (GPCRs) are the largest class of membrane proteins in the human genome. GPCRs act as cell surface signalling proteins and respond to a variety of external signals. They play a pivotal role in many physiological functions and are therefore associated with a multitude of diseases, including cardiovascular, metabolic, neurodegenerative, psychiatric, and oncologic diseases. The 2012 noble Prize in Chemistry was awarded jointly to Robert J. Lefkowitz and Brian K. Kobilka for studies of GPCRs, highlighting the importance of this protein superfamily. GPCRs constitute also the most important family of drug targets in the human body, with 30% of current drugs acting on GPCRs. However, drug discovery targeting GPCRs remains difficult, owing to the restricted structural information on GPCRs related to the instability of these proteins when isolated from their cell membrane environments. There is also a lack of knowledge for the structural and functional consequences of the interactions of small-molecule compounds with GPCR. The aim is to develop methods to study and characterize a full GPCR solubilized in detergents or in native lipid bilayers, both in its free form and in small molecule bound forms, using liquid-state NMR experiments. The aim is to develop NMR-based approaches that will strongly impact the structure-based drug discovery process for the GPCR family
187

Modifications in Cellular Responses of Mononuclear Cells Exposed to Mycobacterium Avium Serovar-specific Glycopeptidolipid and Its Lipopeptide Fragment

Pourshafie, Mohammed R. 12 1900 (has links)
Immunological and ultrastructural changes in mononuclear cells exposed to Mycobacterium avium serovar-specific glycopeptidolipid (GPL) and the chemically derived R-lipid (lipopeptide fragment) were examined.
188

Synthetic Peptides Model Instability of Cardiac Myosin Subfragment-2

Taei, Nasrin 08 1900 (has links)
Hypertrophic cardiomyopathy (HCM), a heart-related abnormality, is the most prevalent cause of sudden death in young athletes at sporting events. A cluster of cardiomyopathy mutations are localized in β-cardiac myosin at the N-terminal region of subfragment-2. Using resonance energy transfer probes, a synthetic peptide model system was developed to study stability of the coiled coil (S2 fragment) structure by determining monomer-dimer equilibrium of the peptide. Fluorescence resonance energy transfer and MacroModel software suite were used to obtain distance measurements along with measurement of coiled coil formation. The model peptide was used to characterize the effects of disease-causing-mutations and examine potential candidate drugs (polyamines) to counteract effects of mutations causing HCM. Distance measurements between donor and acceptor probes obtained by computational simulation and fluorescence resonance energy transfer (FRET) were consistent. Measurements also agreed with simulations of unlabeled wildtype, indicating coiled coil structural stability of the peptide. Interaction of the site-specific antibody with the peptide strongly inhibited dimerization and destabilized coiled coil structure of the peptide. Presence of negatively charged glutamate residues in the region of subfragment-2 strongly suggested a potential interaction site for positively charged polyamines. Binding of certain polyamines, such as poly-L-Lysine 11 residues and poly-D-Lysine 17 residues, demonstrated the ability to enhance dimerization and improve stability of the coiled coil structure, while some other polyamines were shown to have insignificant impact on the structure. In an attempt to characterize the effect of HCM-causing-mutations, peptides containing E924K mutation and lethal mutation E930 deletion were synthesized. Fluorescence resonance probes were conjugated to the mutant peptides to determine coiled coil formation. Results obtained from both dynamic simulations and resonance energy transfer experiments indicated that these mutations strongly inhibit dimerization, and thus, destabilize coiled coil structure of the peptide. Further experiments were conducted using heterodimers containing a chain of wildtype and a chain of mutant peptide. Both E924K & Edel930 mutations destabilized coiled coil formation and prevented dimerization. This peptide model system would provide a promising tool for drug development targeting HCM-causing-mutations along the S2 region of myosin.
189

Fem fragment om måleri

Ingvarsson, Sunniva January 2021 (has links)
This bachelor essay presents some aspects of Sunniva Ingvarssons painting process.  Comparing the painterly act with writing (about the field of her practice) the text aims to grasp some outlooks on the use of words or verbal contentmaking connected to a nearly nonverbal expression.  The painted gestures and markmakings are being discussed as meaningless in a meaningful way, arguing whether the parameters of the established should be taken in consideration in the artistic research, or not.  Based on subjective experiences and some readings including Susan Sontag, Judith Butler (and Friedrich Schlegel) there is an aim to make the reader understand the eventual importance of the un-validated thoughts art possibly can consist of, with permission of only the artist.
190

Denaturants or Cosolvents Improve the Specificity of PCR Amplification of a G + C-Rich DNA Using Genetically Engineered DNA Polymerases

Varadaraj, Kulandaiappan, Skinner, Dorothy M. 01 January 1994 (has links)
We describe conditions that improve the specificity of amplification of a G + C-rich (57% G + C) DNA by PCR. Under standard conditions a 368-bp segment of the approx. 2.1-kb repeat unit of a satellite DNA that accounts for approx. 3% of the genome of the Bermuda land crab, Gecarcinus lateralis, was not amplified specifically. To establish optimal conditions for amplification of the segment of the G + C-rich satellite, we used two genetically engineered enzymes, AmpliTaq DNA polymerase and AmpliTaq DNA polymerase. Stoffel fragment (SF), and a number of denaturants or co-solvents. In the absence of denaturants or co-solvents, amplified products of both enzymes contained non-specific bands upon gel electrophoresis. Addition of certain denaturants or co-solvents to PCR mixtures resulted in the production of the single specific band of the expected size. Reagents that improved specificity of the amplified product were formamide, glycerol, DMSO, Tween-20 and NP-40; on the other hand, urea, ethanol and 1-methyl-2-pyrrolidone (NMP) inhibited amplification. Of the two enzymes, SF was more specific and efficient. The products of AmpliTaq DNA polymerase included one or more extra bands, even in the presence of denaturants or co-solvents, except for glycerol or DMSO.

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