Biomolecule structural fluctuations determine function, regulating numerous biological processes My research has shed light on several interesting cases in which structural fluctuations have been identified to assess functional differences. Chapter 2 discusses the effects of structural rearrangement of the β2-β3 loop on the DNA binding affinity of the type 6 human papillomavirus E2 protein. Chapter 3 investigates the effects of phosphorylation on the C-terminal domain of Cdc37, a protein important in the Hsp90 chaperone cycle. Chapter 4 studies the effects on cyclycization on the conformational fluctuations of a γ-AApeptide used for high-throughput libraries. Chapter 5 is a structural study on a mini-fibril of spider dragline silk, in which a native-like ensemble was generated using temperature replica exchange. Chapter 6 investigates the structural features of repetitive motifs found in spider dragline silk when subject to both dope-like and fiber-like conditions. Chapter 7 elucidates conformational differences between the RXRα and the RXRβ ligand-binding domains and seeks to understand the atomic basis for different ligand binding affinities. This body of work has contributed to the understanding of conformational fluctuations and changes that occur in protein-DNA binding systems, drug-binding, regulation of chaperones via post-translations modifications and spider dragline silk.

The thesis Economic analysis of a chosen company presents economic performance assessment of the company Rabbit Trhový Štěpánov a. s. during five closed accounting period from 2010 to 2014. The first part of the thesis is focused on the theoretical definition individual methods of economic analysis. Followed the practical part, in this are utilized in processing data emerging from company results of individual analysis. The thesis conclusion offers result data summary and evaluation and provides a baseline for recommendations on future company development.

abstract: In desert riparian ecosystems, rivers provide free water but access to that water diminishes with distance producing a steep gradient in the relative importance of water for growth and reproduction of riparian animals and hence, their biodiversity. Previous work suggests that water limited riparian predators eat more prey to meet their water demand where free water is not available. Here I explore the effect of water limitation on prey selection and per capita interaction strengths between a predatory spider ( Hogna antelucana) and two prey species occupying different trophic levels using a controlled field experiment conducted in the riparian forest of the San Pedro River, Cochise County, AZ. Lab measurements of water and energy content revealed that intermediate predators (smaller spiders in the genus Pardosa) had 100-fold higher energy: water ratios than an alternate prey species more basal in the food web (crickets in the genus Gryllus). Given this observation, I hypothesized that water-stressed predatory wolf spiders would select more water-laden crickets but switch to more energy rich Pardosa when water stress was experimentally eliminated. Additionally, I hypothesized that switching by quenched Hogna to Pardosa would reduce predation by Pardosa on Gryllus leading to increased abundance of the basal resource. Finally, I hypothesized that water mediated switching and release of basal prey would be stronger when male Hogna was the apex predator, because female Hogna have higher energetic costs of reproduction and hence, stronger energy limitation. Experimental water additions caused both sexes of Hogna to consume significantly higher numbers of Pardosa but this difference (between water and no-water treatments) did not vary significantly between male and female Hogna treatments. Similarly, strong negative interaction strengths between Hogna and Pardosa led to release of the basal prey species and positive interaction strengths of Hogna on Gryllus. Again strong positive, indirect effects of Hogna on Gryllus did not depend on the sex of the Hogna predator. However, water mediated indirect effects of Hogna (either sex) on Gryllus were the strongest for male Gryllus. These results suggest that water and energy co-dominate foraging decisions by predators and that in managing water-energy balance; predators can modify interaction pathways, sex-ratios of prey populations and trophic dynamics. / Dissertation/Thesis / Masters Thesis Biology 2015

Orientador: José Chaud Netto / Banca: Edilson Divino de Araújo / Banca: Sulene Noriko Shima / Parawixia bistriata é a única espécie da família Araneidae que apresenta comportamento social. Refúgio comunal e cooperação de caça são duas características interessantes observadas nessa espécie. O presente trabalho teve como objetivos analisar a dinâmica populacional das colônias de Parawixia bistriata durante seu desenvolvimento e estudar o comportamento de caça individual das aranhas dessa espécie. Por meio de observações de campo de sete colônias de Parawixia bistriata foi possível verificar que estas passaram por um intenso processo de forrageio, bem como de procura por um hábitat ideal, na medida em que se observa uma constante mudança no local de construção do refúgio comunal. Durante esse processo de forrageio, devido à deficiência na quantidade de recursos, bem como de espaço físico, é comum observar fissões de colônias dessa espécie. Em experimentos realizados na presente pesquisa observou-se que, apesar de ocorrer decréscimo acentuado no número de indivíduos em algumas colônias, a razão sexual das mesmas não foi alterada (1:1) no período em que foi realizada a sexagem dos indivíduos. Também foi observada uma grande tolerância entre indivíduos coespecíficos não aparentados, ou seja, de colônias não irmãs. Essa aceitação confirma a significativa existência de fusões de colônias durante o desenvolvimento dos indivíduos dessa espécie, que reforçam a idéia da formação das super-colônias, mencionada anteriormente por outros autores. No que diz respeito ao comportamento de caça individual em colônias dessa mesma espécie de aranha orbitela, observou-se que estas aranhas conseguem, de certa forma, escolher um determinado tipo de presa. Isso ocorre na medida em que se observa o total desprezo pelas presas de pequeno porte, bem como a preferência pela captura de presas de tamanho grande. Um outro fator importante é o fato de que essas... (Resumo completo, clicar acesso eletrônico abaixo) / Parawixia bistriata is the unique species of Araneidae that shows social behaviour. Communal refuge and cooperative hunting are two interesting features observed in this species. The objectives of this research were to analyze the population dynamics in colonies of Parawixia bistriata and to study the individual predatory behaviour of this species. Field observations of seven colonies of Parawixia bistriata showed that these colonies developed an intense hunting activity and search for an ideal place to build the nest. During these two activities the colonies can separate its members on account of the lack of food or space to build their webs. Although the number of spiders is significantly reduced during the development in some colonies, this research showed that the sex ratio of the colonies is almost 1:1 when it is possible to do the sexual identification. It was also noted that there is a great tolerance between spiders from different colonies and because of this there are fusions of colonies that become supercolonies. In relation to the individual predatory behaviour in Parawixia bistriata it was possible to see that this spider can recognize and choose its prey. Another experiment of this research showed that the spiders refused a small prey or left it after a while, if a bigger prey was captured. It was also observed that the spider "prefers" a big prey than a small one, and the spider feeds on a big prey in the same place of the web where it was caught. This fact can be explained by the existence of intra colonial competition for food and this behaviour maybe is a strategy to avoid the robbery of food by a co-specific that lies beside it / Mestre

A família Theraphosidae é a maior dentre as famílias da subordem Mygalomorphae, apresentando 112 gêneros e 908 espécies. É considerada um grupo monofilético, e está dividida em nove subfamílias. A subfamília Theraphosinae é restrita ao continente americano. É caracterizada por apresentar o bulbo com êmbolo distalmente largo e grosso, com presença de quilhas, e o subtegulum largo, que se estende até a metade do tegulum, e também pela presença de pêlos urticantes de tipo I, III e IV (Raven, 1985, Pérez-Miles et al. 1996). Homoeomma foi revisado em 1972, quando possuía um elenco de dez espécies. Atualmente, o gênero apresenta 14 espécies, com distribuição restrita à América do Sul (Argentina, Brasil, Colômbia, Peru e Uruguai). O holótipo de Homoeomma pictum possui bulbo copulador e apófise tibial da perna I semelhante a Thrixopelma, sendo transferido para esse gênero. O tipo da espécie Homoeomma peruvianum também foi examinado e este provavelmente não pertence ao gênero, porém, não foi possível estabelecer um novo gênero para essa espécie. O holótipo de H. nigrum, uma fêmea com espermateca danificada, não foi examinado. Essas duas espécies são consideradas species inquirenda. As espécies H. stradlingi e H. strabo passam a ser sinônimos-júnior de Homoeomma familiare. Homoeomma hirsutum é considerada sinônimo-júnior de H. montanum. Na análise cladística, foram incluídas oito espécies de Homoeomma, além das espécies Grammostola mollicoma, Magulla obesa, Maraca cabocla, Plesiopelma flavohirtum, P. longisternalis, Tmesiphantes nubilus, Gen. n. sp.1. Para o enraizamento, foi utilizada Oligoxytre caatinga (Theraphosidae, Ischnocolinae). A análise resultou em dois cladogramas igualmente parcimoniosos, com 73 passos. O consenso estrito (75 passos) possui a seguinte topologia: (Oligoxystre caatinga ((((Homoeomma stradlingi (H. montanum (H. brasilianum (H. uruguayensis (H. elegans H. villosum)))))(Maraca humile Maraca cabocla ))(Plesiopelma longisternalis Cyriocosmus ritae (Gen. n. simoni Gen. n. sp1 Gen. n. flavohirtum )))(Tmesiphantes nubilus (Grammostola mollicoma Magulla obesa )))). Apenas seis das oito espécies de Homoeomma formam um agrupamento monofilético. Homoeomma simoni e Plesiopelma flavohirtum foram transferidas para um gênero novo, junto a uma espécie nova. O Gen. n. é bem suportado por quatro sinapomorfias. Homoeomma humile é grupo-irmão de Maraca cabocla, sendo transferida para este gênero, compartilhando três características sinapomórficas não exclusivas. O gênero Maraca é grupo-irmão de Homoeomma. As seis espécies restantes de Homoeomma formam um grupo monofilético, com três sinapomorfias não exclusivas: apófise digitiforme do bulbo grande, ângulo de 90º-135º do êmbolo em relação ao bulbo e metatarso I dos machos curvo na base. São descritas pela primeira vez as fêmeas de H. brasilianum e subtegulum. A distribuição das espécies foi atualizada e ampliada com novos registros. / Theraphosidae is the larger family within suborder Mygalomorphae, with 112 genera and 908 species. It is considered a monophyletic group, divided into nine subfamilies. The subfamily Theraphosinae is restricted to America continent. It is characterized by the presence of a papal bulb with wide and thick embulus presenting keels, wide subtegulum, extending down the bulb to half of tegulum length and by the presence of urticating hairs type I, III and IV. The present work aims the increase of the taxonomic and phylogenetic subfamily knowledge, throughout the study of Homoeomma genera Ausserer, 1871. Homoeomma was revised in 1972, including ten species on it. Nowadays, the genera has 14 species, with distribution restricted to South America (Argentina, Brazil, Colombia, Peru e Uruguay). The Homoeomma pictum holotype presents copulatory bulb and tibial apophysis of leg I that resemble Thrixopelma, so the species is transfered to these genus. The type of Homoeomma peruvianum was also examined and probably do not belong to the genus. Unfortunately, it was not possible to establish a new genus to this species. H. nigrum´s holotype, a female presenting a severed spermathecae, wasn\'t examined. These two species are considered species inquireda. H. stradlingi e H. strabo are established as junior-synonyms of H. familiare. And Homoeomma hirsutum is considered junior-synonym of. 7 The eight remaining species of Homoeomma were included in cladistic analysis, enclosed with Grammostola mollicoma, Magulla obesa, Maraca cabocla, Plesiopelma flavohirtum, P. longisternalis, Tmesiphantes nubilus, Gen. n. sp.1. Oligoxytre caatinga (subfamily Ischnocolinae) was used to set the root. The analysis resulted in two equally parsimonic trees, with 73 steps. The strict consensus (75 steps) presents this topology: (Oligoxystre caatinga ((((Homoeomma stradlingi (H. montanum (H. brasilianum (H. uruguayensis (H. elegans H. villosum)))))(Maraca humile Maraca cabocla ))(Plesiopelma longisternalis Cyriocosmus ritae (Gen. n. simoni Gen. n. sp1 Gen. n. flavohirtum )))(Tmesiphantes nubilus (Grammostola mollicoma Magulla obesa )))). The eight species of Homoeomma do not form a monophyletic group. Three transferences are proposed: Homoeomma simoni and Plesiopelma flavohirtum are transfered to a new genus, with a new species. Gen. N. is well supported by four synapomorphies. H. humile is the sister group of Maraca cabocla, sharing three non exclusive synapomorphies. The genus Maraca is considered sister group of Homoeomma. The six remaining species of Homoeomma form a monophyletic group with three non exclusive synapomorphies: a big papal bulb digitform apophysis, a 90º-135ºangle between embulus and bulb and males metatarsus I presenting a basal curvature. The females of H. brasilianum e H. elegans are described for the first time. Species distribution is updated and enlarged with new records.

The focus of this thesis is on the liminal space, limen being Latin for threshold. The liminal space is used as a means of figuring and reading artworks that appear to be in a process of becoming and disappearing. A dialectical and reciprocal reading is made of Bourgeois’ “neo-Baroque” artwork Spider (1997) and Michelle Key’s Betwixt-in-Between (2004). Liminality here is discussed within the theoretical framework of several key conceptual concerns, including abjection (as examined principally by Julia Kristeva), Baroque thought (as discussed by Mieke Bal, Gilles Deleuze, Jacques Lacan and Slavoj Žižek) and allegory (as figured primarily by Walter Benjamin and commentators on Benjamin’s writings). What links these concerns are their focus on indeterminacy, instability, and process as opposed to certitude and finitude. The exploration of the inscription of time in space; that is the temporal process, which gives rise to, which produces, the spatial dimension, is attempted in order to make meaning, however provisionally, of what may be argued to destabilise meaning and to consider possibilities for both art-making and interpretation that would engage critically with this instability.

Orientador: Stephen Hyslop / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T16:25:10Z (GMT). No. of bitstreams: 1 Sutti_Rafael_M.pdf: 1515999 bytes, checksum: 405faa9b9c1e523dc2e0bf64268e2bdd (MD5) Previous issue date: 2011 / Resumo: A hialuronidase (Hyase) de peçonha contribui para a difusão da peçonha do local da inoculação. Neste trabalho, foi purificada e caracterizada a Hyase da peçonha da Vitalius dubius (Araneae, Theraphosidae), uma aranha caranguejeira encontrada no sudeste do Brasil. A peçonha obtida por estimulação elétrica de machos e fêmeas adultas foi fracionada por cromatografia em gel filtração em uma coluna Superdex 75 (tampão acetato de sódio 0,1 M, pH 6, contendo 0,15 M de NaCl), a um fluxo de 1 ml/min. O perfil de eluição foi monitorado a 280 nm e frações de 1,5 ml foram coletadas e analisadas para Hyase. As frações ativas foram reunidas e aplicadas em uma coluna de afinidade heparin-Sepharose (em acetato de sódio 0,01 M, pH 6). A coluna foi lavada com o mesmo tampão e as proteínas foram eluídas com um gradiente linear de NaCl (0-1 M). As frações ativas foram agrupadas e avaliadas quanto à pureza por SDS-PAGE e RP-HPLC. O pH ótimo, a estabilidade térmica, a presença das isoformas, e a neutralização por flavonóides e antivenenos comerciais também foram avaliadas. A Hyase foi purificada em duas etapas cromatográficas, com atividade específica de 148 unidades de redução de turbidez (TRU)/mg (peçonha: 36 TRU/mg; fator de purificação de ~ 4). A Hyase apresentou uma massa molecular estimada em 43 kDa por SDS-PAGE, que não foi afetada por ?-mercaptoetanol. Zimografia em gel contendo ácido hialurônico confirmou atividade sobre o substrato. O pH ótimo foi de 4 a 5, com atividade ótima à 37°C. A Hyase manteve estabilidade até 60°C, mas perdeu rapidamente a atividade em altas temperaturas; a atividade se manteve após vários ciclos de congelamento e descongelamento. A atividade enzimática foi totalmente inibida por dois (apigenina e naringina) dos cinco flavonóides testados. A concentração de NaCl (0,05-1 M) não influenciou a atividade. A enzima apresentou maior atividade com ácido hialurônico em relação ao sulfato de condroitina A e foi totalmente neutralizada pelo antiveneno aracnídeo polivalente contra peçonha de aranha-marrom (Loxosceles sp.), aranha armadeira (Phoneutria nigriventer) e escorpião amarelo (Tityus serrulatus), mas não por antivenenos contra peçonha de lagarta (Lonomia obliqua), escorpião (T. serrulatus e Tityus bahiensis) ou serpente (Bothrops, Crotalus e Micrurus). A Hyase aumentou a permeabilidade vascular na pele dorsal de ratos. As propriedades bioquímicas da Hyase foram semelhantes às Hyases encontradas em outras peçonhas. A neutralização pelo antiveneno aracnídeo (mas não pelo escorpiônico) indicou que esta enzima compartilha epítopos antigênicos com enzimas semelhantes em peçonhas de outras aranhas / Abstract: Venom hyaluronidase (Hyase) contributes to the diffusion of venom from the site of inoculation. In this work, we purified and characterized Hyase from the venom of Vitalius dubius (Araneae, Theraphosidae), a large theraphosid found in southeastern Brazil. Venom obtained by electrical stimulation of adult male and female V. dubius was initially fractionated by gel filtration on Superdex 75 (in 0.1 M sodium acetate, pH 6, containing 0.15 M NaCl), at a flow rate of 1 ml/min. The elution profile was monitored at 280 nm and 1 ml fractions were collected and assayed for Hyase. Active fractions were pooled and applied to an affinity column of heparin-Sepharose (in 0.01 M sodium acetate, pH 6). The column was washed with the same buffer and proteins were eluted with a linear gradient of NaCl (0-1 M). Active fractions were pooled and assessed for purity by SDS-PAGE and RP-HPLC. The pH optimum, heat stability, presence of isoforms and neutralization by flavonoids and commercial antivenoms were also assessed. Hyase was purified in two chromatographic steps with a specific activity of 148 turbidity reducing units (TRU)/mg (venom: 36 TRU/mg; purification factor of ~4). Hyase had a molecular mass of 43 kDa by SDS-PAGE that was unaffected by ?-mercaptoethanol. Zymography in gels containing hyaluronic acid indicated that there were no isoforms. The pH optimum was 4-5, with optimal activity at 37°C. Hyase was stable up to 60°C, but rapidly lost activity at higher temperatures and maintained activity after several freeze-thaw cycles. Enzyme activity was completely inhibited by two (apigenin and naringin) of five flavonoids tested. The NaCl concentration (0.05-1 M) did not influence activity. Hyase had greater activity towards hyaluronic acid compared to chondroitin sulphate and was completely neutralized by polyvalent arachnid antivenom raised against brown spider (Loxosceles spp.), banana spider (Phoneutria nigriventer) and yellow scorpion (Tityus serrulatus) venoms, but not by antivenoms to caterpillar (Lonomia obliqua), scorpion (T. serrulatus and Tityus bahiensis) or snake (Bothrops, Crotalus and Micrurus species) venoms. Hyase increased vascular permeability in rat dorsal skin. The biochemical properties of this Hyase were similar to other venom Hyases. The neutralization by arachnid but not scorpion antivenom indicated that this enzyme shared antigenic epitopes with similar enzymes in other spider venoms / Mestrado / Farmacologia / Mestre em Farmacologia

No description available.

Circadian clocks are endogenous time keeping mechanisms that are ubiquitous among animals. They enable coordination of many essential biological and metabolic processes in relation to the 24 hour light cycle on earth. However, there are many habitats on earth that are not subject to this light cycle. This study aims to look at the potential genetic drift of the circadian rhythm of a subterranean spider, Meta ovalis, as well as gathering general natural history information on this under-studied spider. This study will fill general gaps in knowledge of this spider and its habitat, highlight the importance of studying organisms within a subterranean environment, and place importance on cave conservation and acquiring knowledge of these specialized, and sensitive species. This study integrates circadian and foraging theory to evaluate species as circadian specialists and generalists based on how narrowly or widely their activity is spread over the 24 h cycle. We suggest that M. ovalis benefits from a generalist strategy, showing small bursts of focused activity widely dispersed across the 24 h cycle, allowing it to capture prey opportunistically whenever it is available. Live spiders were collected from area caves, monitored in an environment controlled for light and temperature, and returned to their cave of origin. The activity of each spider was analyzed for differences in circadian activity among and between populations to determine if there is a significant drift of the circadian strategy between isolated populations of Meta ovalis. We expect to see a different circadian strategy implemented between populations due to drift from the spiders being isolated from other populations.

This diploma thesis deals with the financial health of the three largest commercial insurance companies of the Czech insurance market. The literature review part is focused on the financial health theme, largely treating the financial analysis in particular. Also, the literature review is concerned with in rating of insurance companies as well as with the level indicators of the insurance market. The practical part is focused on the development of macroeconomic indicators in the period of 2012-2016 and the development of the Czech insurance market. Next in this part, the financial analysis of the commercial insurance companies is presented. The assessment of relative, performance and market value indicators makes the substance of the part. The financial analysis is completed with the spider analysis of the period under review. Then the aggregate result comparison of the insurance companies and the industry follows. The financial analysis gives rise to the econometric model. The last part seeks to compare individual results with the analysis procedures in a broad context.