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Portugal-Nunes, Diogo João. "Bioethanol production from SSLs: S. stipitis vs S. cerevisiae." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/11279.
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Mestrado em Biotecnologia - Biotecnologia Industrial e Ambiental<br>O objectivo desta dissertação foi a comparação da produção de bioetanol de 2ª geração por Scheffersomyces stipitis (em suspensão e imobilizada) e por duas estirpes industriais de Saccharomyces cerevisiae. Os substratos utilizados para a realização das fermentações foram os Licores de Cozimento ao Sulfito Ácido (SSLs) provenientes de madeira de resinosas (HSSL) e de madeiras de folhosas (SSSL – Domsjö hydrolysate). O HSSL e o SSSL são sub-produtos da indústria de pastas de papel, resultando do processo de cozimento ao sulfito com magnésio e sódio, respetivamente. Além de lenhosulfonatos, estes SSLs contêm monossacarídeos, destacando-se a glucose, xilose e manose. O ácido acético, composto inibidor da fermentação alcoólica por leveduras, também está presente em concentrações relativamente elevadas (≥ 5.0 g . L-1). O HSSL foi pré-tratado físico-quimicamente e submetido a uma remoção biológica de inibidores com P. variotii, enquanto o Domsjö hydrolysate foi utilizado sem qualquer tratamento. S. stipitis e S. cerevisiae são leveduras extensamente estudadas devido à sua capacidade de fermentação de pentoses e hexoses, respetivamente.
Num estágio prévio às fermentações dos SSLs, as leveduras foram pré-adaptadas em 60% HSSL ou 40% SSSL. Os máximos de rendimento (0.440 g etanol . g açúcares-1) e produtividade em etanol (0.885 g etanol . L-1 . h-1) foram obtidos nas fermentações com S. cerevisiae TMB 3500 em SSSL, sendo estas as variáveis com maior potencial para aplicação industrial. Embora a cultura suspensa de S. stipitis tenha resultado numa menor produtividade (0.010 g etanol . L-1 . h-1), a optimização do fornecimento de oxigénio ao biorreator deverá conduzir ao aumento da produtividade volumétrica em etanol.
A imobilização celular e o controlo do pH em 5.5 nas fermentações com S. stipitis melhoraram a eficiência fermentativa ao aumentarem a produção de etanol em 1.3 e 1.6 vezes, respetivamente. Quando aplicadas simultaneamente, estas duas condições aumentaram o rendimento em etanol 2.2 vezes, sugerindo que (i) a imobilização numa matriz de alginato de cálcio protegeu a levedura dos inibidores químicos e que (ii) o controlo de pH em 5.5 foi determinante para a produção de etanol a partir de HSSL biologicamente pré-tratado.
Os resultados comprovam que ambos os SSLs são potenciais substratos para a produção de bioetanol de 2ª geração usando S. stipitis ou S. cerevisiae, sob o conceito de biorefinaria.<br>The aim of this work was the comparison of second-generation bioethanol production by Scheffersomyces stipitis (free-culture and immobilized) and two Saccharomyces cerevisiae industrial strains, using Hardwood Spent Sulphite Liquor (HSSL) or Domsjö hydrolysate (SSSL) as substrate. HSSL and SSSL are side products of pulp and paper industry, from magnesium and sodium-based acidic sulphite pulping, respectively. Besides sulphonated lignin, SSLs contain fermentable sugars, mainly glucose, xylose and mannose. Acetic acid, a known inhibitor of ethanol fermentation by yeasts, is also present in a relatively high content (≥ 5.0 g . L-1). HSSL was previously physico-chemically pretreated and bio-detoxified with P. variotii, whereas SSSL was used without any treatment. S. stipitis and S. cerevisiae are the most widely studied pentose and hexose-fermenting yeasts, respectively.
Before fermentations in SSLs, all yeast strains were pre-adapted by growing them in 60% HSSL or 40% SSSL. The highest maximum ethanol yield (0.440 g ethanol . g sugars-1) and productivity (0.885 g ethanol . L-1 . h-1) were obtained using S. cerevisiae TMB 3500 and SSSL. Suspended S. stipitis achieved a lower ethanol productivity (0.010 g ethanol . L-1 . h-1) but further optimization on the supplied oxygen in the fermentor might lead to higher ethanol productivity. Immobilization and pH control at 5.5 on S. stipitis fermentations improved the fermentation efficiency, increasing up the ethanol production by 1.3-fold and 1.6-fold, respectively. When applied simultaneously, these two conditions increased the ethanol yield 2.2-fold, suggesting that (i) immobilization with a calcium-alginate matrix protected the yeast from the inhibitory compounds and (ii) the controlled pH at 5.5 was essential for ethanol production from bio-detoxified HSSL.
Results showed that both SSLs are potential substrates for the production of 2nd generation bioethanol by S. stipitis or S. cerevisiae, under the biorefinery concept.
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Kejser, Katrine. "“Pop a titty for the boys” -A qualitative study of negative communication towards femalestreamers on Twitch." Thesis, Örebro universitet, Institutionen för humaniora, utbildnings- och samhällsvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-92543.
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The development of technology has created many platforms for entertainment, participatorycommunities and socialization online. One of the largest current platforms for live streamingis Twitch.tv with a focus on gaming and eSports. This is a male-dominated field wherewomen often face harassment and a non-welcoming community. This paper is a qualitativestudy of the negative communication towards female streamers on Twitch with a focus onthe context in which said communication takes place. The aim of the study is to understandthe circumstances in which negative communication occurs and how it changes dependingon context. The study takes a qualitative approach and analyses the content of six streamsfrom five different channels, as well the negative communication in their chat room. Theresults show that negative communication varies depending on the content as well as thenature of the community built around the channel.
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Veselovský, Matej. "Vytvoření monitorovacího a profilovacího řešení nad BI systémem." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2017. http://www.nusl.cz/ntk/nusl-318361.
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This master’s thesis focuses on monitoring and profiling multidimensional database and reports. The project was created in MS SSIS to this purpose and it contains 4 ETL packages. The thesis is divided into three main sections. First section consists of theoretical background needed to accomplish the goal. In second section there is analysis of the company for which is the solution created and in the third part of the thesis there is described the proposal and it’s solution. Proposal of the solution and the solution itself was created in MS Visual Studio 2015, MS SQL Management Studio and Power BI.
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Lundstedt, Mattias, and Axel Norell. "Prototyp för dynamiskt beslutsstöd." Thesis, Linköpings universitet, Interaktiva och kognitiva system, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-108954.
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Företaget Nethouse har haft uppdraget att kravställa, utveckla och implementera ett verksamhetssystem åt Sveriges Skorstensfejaremästares Riksförbund (SSR). Medlemsföretagen i SSR bedriver sotarverksamhet på uppdrag av Sveriges kommuner och är beroende av insamlad data kopplad till deras verksamhet. I det nyutvecklade systemet, som går under namnet Ritz, samlas informationen i en central databas och är tillgänglig för flertalet intressenter med hjälp av ny teknik och modernare lösningar. Systemet är helt webbaserat och körs som en molntjänst, tillgängligt via antingen en webbsida eller som mobilapplikation. Åtkomsten av data baseras på företagsnivå på ”stämplad” data i databasen och för att reglera åtkomsten för företagsanvändare till respektive företags data används rollbaserad åtkomstkontroll. Detta examensarbete har syftat till att utveckla en prototyp till en beslutsstödslösning för dynamisk åtkomst till de datamängder som lagras inom Ritz. Nethouse har efterfrågat en prototyp för en BI-lösning som visar på möjligheter och fördelar för intressenter till Ritz med att implementera en sådan. Då integration och förvaltning är viktiga faktorer för Nethouse har ett krav på prototypen varit att den utvecklats inom Microsofts programvaror, precis som resten av Ritz. Prototypen färdigställdes genom konstruerandet av ett centralt data warehouse enligt Ralph Kimballs metodologier och genom implementation av en OLAP-kub byggd i Microsoft SSAS. Dataöverföringen från datakällorna till beslutsstödslösningens data warehouse skedde genom utvecklandet av en ETL-process i Microsoft SSIS. Den resulterande kuben har främst utformats för att kunna besvara den sortens frågor som länsstyrelser ställer till sotarföretag i kontrollsyfte och stöder förfrågningar mot de två centrala affärsprocesserna sotning och brandskyddskontroll. Dessa förfrågningar kan filtreras på flertalet dimensioner som exempelvis tid, utförare, status och kontrollutfall. Prototypen begränsar även åtkomst till den information som användare har rätt att ta del av genom att koppla samman användare och objekt till geografiska indelningar som kallas distrikt. Denna dynamiska säkerhetslösning ger goda förutsättningar för att kunna hantera förändringar i användarnas behörighet i framtiden. Genom den utvalda lösningen behålls den dynamiska naturen i systemet, då åtkomst till beslutsstödstjänsten kan fås genom flertalet källor som stödjer uppkoppling mot Microsofts multidimensionella beslutsstödslösningar, bland annat Excel och SQL Server Reporting Services.
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Carlsson, Jacob, and Edison Gashi. "SSDs påverkan på MySQL: En prestandajämförelse." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-21266.
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Solid State Drives (SSD) blir idag allt vanligare som lagringsmedium och håller på att bli ett alternativ till magnetiska hårddiskar. Denna studie+ har undersökt hur man på bästa sätt kan utnjytta SSDer i en MySQL-databas. Undersökningen genomfördes med hjälp av experiment där prestandamätningar gjordes för att få en klar bild på i vilken konfiguration av SSDs som ger bäst prestanda i MySQL. Mätverktygen som användes var sql-bench och mysqlslap. Resultaten visar att en databas på en enskild SSD presterar lika bra som en databas med SSD-cache under majoriteten av mätningarna och visar bättre resultat än resterande konfigurationerna som var en databas på hårddisk och transaktionsloggen på en SSD.<br>Solid State Drives (SSD) are now becoming more common as storage and is about to become an alternative to magnetic disks. This report studied how to best utilize SSDs in a MySQL database. This study was carried out using experiments in which performance benchmarks were made to get an accurate view on which configuration of SSDs that gives the best performance in MySQL. The benchmarks where made with sql-bench and mysqlslap. The results indicate that a database using only SSD storage performs equal to a database of solid-state cache under the majority of the tests and shows better results than the remaining configurations that include a database on a single hard drive and a configuration with the transaction log on a SSD.
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Roberto, Miguel Augusto Inácio. "Smart & Simple Business Solutions (SSBS)." Master's thesis, NSBE - UNL, 2010. http://hdl.handle.net/10362/10319.
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Petrusic, Dejan. "En studie av SSL." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3537.
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Dokumentet är ett resultat av studier gjorda under kursen Kandidatarbete I Datavetenskap. Arbetet utforskade, genom fallstudie, två egenskaper av distribuerade informationssystem och relation mellan dessa: säkerhet och prestanda. Målet med fallstudien har varit att belysa nackdelen med användning av Secure Socker Layer (SSL) dvs. dess effekt på hastigheten och fördelen med SSL, dvs. SSL:s roll i informationssäkerhetsarbetet. Arbetet visar hur prestanda i ett tillämpad distribuerat informationssystem kan påverkas av en SSL tillämpning. Systemets responstid testades för skillnader mellan en SSL säkrad uppkoppling och utan. Det testade systemet var ett bokningssystem som används för administration av resor, utvecklat i DotNet utvecklingsplattform. Arbetet har dessutom visat genom studien av informationssäkerhetsstandarden ledningssystem för informationssäkerhet (LIS) vilken plats som SSL protokollet har i informationssäkerhetsarbetet i organisationer. Metoden för jämförelse utvecklades och baserades på interaktionsmodellen. Hypotesen för arbetet var att mjukvara som tillämpar SSL gör att responstiden blir längre men gör också att informationssystemet uppfyller krav enligt standarden för ledningssystem av informationssäkerhet SS-ISO/IEC 17799 och SS 62 77 99-2. Hypotesen bekräftades då resultatet för mätningen visade en ökning på 37,5 % i medel för klienten med säkrad SSL uppkoppling och att resultatet av LIS studien visade att organisationer uppfyller viktiga krav ställda i standarden genom at ha en SSL säkrad kommunikation i sitt informationssystem.<br>This study shows the impact of SSL application on performance in a distributed information system. Further, the case study shows also, through studies of information security standard SS-ISO/IEC 17799, the place that SSL has in applying information security in organisations.<br>dejanpetrusic@hotmail.com, is00dpe@student.bth.se
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Homaidi, Omar Al. "Data Remanence : Secure Deletion of Data in SSDs." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5165.
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The ongoing fast pace research in hardware and software technology has resulted in memory devices efficient and faster than ever before. However, the issue of security of the contained data is rarely discussed. There is an evident capability of these devices to retain data even when it is erased. In this thesis, a study is conducted to qualitatively analyze the extent to which data deletion is important and why secure deletion should be applied. Afterwards, following the sequential exploratory procedure, this paper presents an analysis of methods used to recover the data after being deleted in addition to the techniques used to securely delete this data. Based on this study, some recommendations are made to ensure the safety of data.
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Vinje, Eivind. "Educational implementation of SSL/TLS." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13834.
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Bradley, Jeremy T. "The SSL Reference Implementation Project." Thesis, University of Bristol, 2000. http://hdl.handle.net/1983/916f1961-2fc1-461e-b76b-2c5d9fb18a5e.
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Madron, Lukáš. "Datové sklady a OLAP v prostředí MS SQL Serveru." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-235916.
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This paper deals with data warehouses and OLAP. These technologies are defined and described here. Then an introduction of the architecture of product MS SQL Server and its tools for work with data warehouses and OLAP folow. The knowledge gained is used for creation of sample application.
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Bijanskienė, Simona. "Kolektyvinės tapatybės formavimas SSRS ir ES: ekonominio veiksnio įtaka." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080610_140515-88047.
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Šio magistrinio darbo pavadinimas „Kolektyvinės tapatybės formavimas SSRS ir ES: ekonominio veiksnio įtaka“. Istorinės ribos apima laikotarpį nuo SSRS susikūrimo iki šių dienų aktualijų, žodis "formavimas" nurodo analizuojamo proceso t��stinumą. Pagrindinė darbo analizės ašis – kolektyvinė tapatybė.
Darbo pagrindinis tikslas yra įvertinti ES kolektyvinio tapatumo formavimo perspektyvumą, remiantis Sovietų Sąjungos patirtimi ir nustatyti ekonominio veiksnio ryšį su kolektyvinio tapatumo formavimo procesu. Siekiant užsibrėžtų tikslų, reikia atlikti šiuos išsikeltus uždavinius: visų pirma, reikia išsiaiškinti kaip yra konstruojamas kolektyvinis tapatumas, kokie veiksniai tai lemia ir kokia yra ekonominio veiksnio reikšmė kolektyvinio tapatumo formavimui; antra, reikia išanalizuoti SSRS kolektyvinio tapatumo formavimo trūkumus; trečia, reikia išanalizuoti ES kolektyvinio tapatumo formavimo ypatumus bei į perspektyvą nukreiptą formavimo politiką, įvertinant ekonominio veiksnio svarbą; ketvirtą, reikia palyginti ES ir Sovietų Sąjungos kolektyvinio tapatumo formavimo specifiką, remiantis gautais duomenimis, padaryti išvadas.
Darbe yra keliamos šios hipotezės:
1. ekonominis veiksnys yra svarbus kolektyvinio tapatumo formavimo procese;
2. kolektyvinio tapatumo formavimo specifika SSRS ir ES turi sąryšio taškų, tai yra - juos įtakoja tie patys veiksniai;
3. ES turi daugiau perspektyvų suformuoti kolektyvinį tapatumą nei SSRS.
Darbe taikomi tyrimo metodai: analitinis – aprašomasis... [toliau žr. visą tekstą]<br>The title of this master thesis is “Formation of Collective Identity in USSR and EU: Impact of Economic Factor“. It defines historical period from USSR foundation till nowadays. The main aspect according to which these multinational blocks are analyzed is collective identity. Special efforts are given to analyze factors which have impact to collective identity formation, but the biggest attention is paid to analyze importance of economic factor.
Identity – the sense of dependence. This concept at one time contains as the connective as also separative elements. This is a result of identification process which helps to define human or group exceptional indications.
As individual or collective identity formation problems are widely discussed in today’s society discourses. Its importance is comprehensible as to the individual as also to the communities behavior motivation. The perception of identity allows to know better your historical or cultural roots, and also to know yourself and others better. But the concept of identity is so wide and variant, that it leaves a lot of place to the following discussions. This work appoints a lot of attention to collective identity forming and it’s specific.
Actuality of the topic remains also in today’s political discourses undisputed – if we clear, how to construct common identity it would emerge a possibility to evaluate, what main mistakes in it forming maid USSR and what perspectives in common identity constructing has EU. This... [to full text]
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Pastuszek, Jakub. "Extrakce dešifrovaného provozu z SSL spojení." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2019. http://www.nusl.cz/ntk/nusl-399194.
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Cílem této práce je vyvinout aplikaci schopnou dešifrovat zabezpečená spojení a přeposlat dešifrovaná data na jinou stanici v síti pro další analýzu. Daná aplikace vybízí k nelegálním účelům, avšak zamýšleným použitím výsledného produktu jsou legální odposlechy. Pro tuto práci byla z množiny nástrojů vybrána aplikace SSLsplit díky jejím vlastnostem a výkonnosti. Toto rozhodnutí bylo na základě srovnávacích testů a porovnání vlastností. Pomocí vlastního certifikátu SSLsplit podepisuje certifikáty cílových serverů, které jsou vytvářené za běhu. Spuštěná aplikace běží v režimu transparentní proxy přímo na centrálním prvku dané sítě (routeru). SSLsplit provádí man-in-the-middle útok mezi klientem a serverem bez toho, aby to některá ze stran zaznamenala. Dále umožnuje dešifrovaný obsah odeslat na předem daný uzel v síti pro jeho další zpracování. Pro možnost snažší konfigurace SSLsplitu byla implementována integrace do netc rozhraní. Aplikace byla otestována za účelem zjištění jejich výkonnostních limitů. Výkonnostní testy výsledného řešení ukazují značný pokles počtu transakcí za sekundu (TPS) při použití SSLsplit v porovnání s pouhým přeposíláním provozu. Funkce zrcadlení významně neovlivňuje počet TPS ani neomezuje samotný SSLsplit. Výsledky ukazují, že SSLsplit je schopen reálného provozu s určitým omezením.
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PINABIAUX, NOWAK VERONIQUE, and PATRICE PINABIAUX. "Sclerose systemique sans sclerodermie : ssss ; a propos de 12 observations." Lille 2, 1991. http://www.theses.fr/1991LIL2M037.
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Akyay, Ilkay. "Replication of Akers' SSSL Model on Turkish Male Narcotics Arrestees." VCU Scholars Compass, 2007. http://scholarscompass.vcu.edu/etd_retro/63.
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This research examines the substance abuse severity problem of the male narcotics arrestees of Turkey within the framework of Akers' Social Structural and Social Learning (SSSL) model. The SSSL model is tested to understand the impact of social structural factors on drug abuse severity of narcotics offenders, in mediation of social learning process. The research design consists of secondary data analysis and modeling techniques to test the hypotheses pertaining to the SSSL model. The data, consisting of 1,647 male cases, have been obtained from the TUBIM Program. The U.S. ADAM Program year 2003 data including 6,730 cases have also been utilized with the purpose of observing the similarities and/or differences among substance abusers across the nations, as described in Chapter 5. Accordingly, the narcotics criminals of Turkey and the U.S. were compared in terms of demographic status, criminal background, substance abuse behavior and state of substance related treatment. Eventually, it was found that substance abusing populations across these two nations are significantly different. In the second phase of the study, Akers' SSSL model was developed and tested on the male narcotics offenders of Turkey. Structural Equation Modeling (SEM) analysis was used to test the hypotheses of the study. A model for the drug offenders whose last charge is drug related (substance abuse or substance distribution) was developed and the model's robustness was tested on those narcotics offenders who have reported committing property and violent offenses before the last charge. It is found that the impact of the social factors on drug abuse and dependence behavior through social learning constructs is non-significant except for the age variable for the drug related offenders subset. Furthermore, the impact of all social structural factors on the seriousness of substance abuse in the mediation of social learning constructs is insignificant for the property and violent offenders subset. Also, the social learning construct of the property and violent offenders' subset does not significantly influence the seriousness of substance abuse.
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Xia, Qianbin. "Towards Design and Analysis For High-Performance and Reliable SSDs." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4904.
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NAND Flash-based Solid State Disks have many attractive technical merits, such as low power consumption, light weight, shock resistance, sustainability of hotter operation regimes, and extraordinarily high performance for random read access, which makes SSDs immensely popular and be widely employed in different types of environments including portable devices, personal computers, large data centers, and distributed data systems.
However, current SSDs still suffer from several critical inherent limitations, such as the inability of in-place-update, asymmetric read and write performance, slow garbage collection processes, limited endurance, and degraded write performance with the adoption of MLC and TLC techniques. To alleviate these limitations, we propose optimizations from both specific outside applications layer and SSDs' internal layer. Since SSDs are good compromise between the performance and price, so SSDs are widely deployed as second layer caches sitting between DRAMs and hard disks to boost the system performance. Due to the special properties of SSDs such as the internal garbage collection processes and limited lifetime, traditional cache devices like DRAM and SRAM based optimizations might not work consistently for SSD-based cache. Therefore, for the outside applications layer, our work focus on integrating the special properties of SSDs into the optimizations of SSD caches. Moreover, our work also involves the alleviation of the increased Flash write latency and ECC complexity due to the adoption of MLC and TLC technologies by analyzing the real work workloads.
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Ryzhkov, Pavel. "Bioengineering of S-layers: molecular characterization of the novel S-layer gene sslA of Sporosarcina ureae ATCC 13881 and nanotechnology application of SslA protein derivatives." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1204126129404-82781.
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S-layer proteins of S. ureae ATCC 13881 form on the cell surface an S-layer lattice with p4 square type symmetry and a period of about 13.5 nm. These lattices were shown to be the excellent nanotemplates for deposition of regular metal clusters. The synthesis of the S. ureae S-layer protein is highly efficient, the protein accounts for approximately 10-15 % of the total cell protein content, judged by the SDS-PAGE results. Besides, the S-layer protein production is tightly regulated, since only negligible amounts of S-layer proteins are observed in the medium at different cell growth phases. At the same time, mechanisms of the regulation of S-layer protein synthesis are poorly understood. As several hundreds of S-layer proteins are produced per second during the cell growth, the S-layer gene promoters are among the strongest prokaryotic promoters at all. However, little is known about factors regulating the expression of S-layer genes, furthermore, no experimental identification of other upstream regulatory sequences except for -35/-10 and RBS sequences was presented to our knowledge to date. A sequence of the S-layer gene of S. ureae ATCC 13881, encoding the previously described S-layer protein, was identified in this work by combination of different approaches. The largest part of the gene, excluding its upstream regulatory and ORF 5’ regions, was isolated from a genomic library by hybridization. The sequence of the isolated fragment proved to contain additionally an 1.9 kb non-coding region and an incomplete 0.8 kb ORF region in its 3’-part. No RBS sequence and apparent promoter regions could be identified in front of the latter sequence, suggesting that it might represent a pseudogene sequence. The sequences of the 5’ and upstream regions of the S. ureae ATCC 13881 S-layer gene were identified by combination of PCR-sequencing and chromosome walking. Totally, a sequence of the 6.4 kb long region of S. ureae genomic DNA was established. The sequence of the S. ureae S-layer protein was deduced from the respective gene sequence and agreed with the peptide sequences, obtained after N-terminal sequencing of tryptic peptides of the S. ureae ATCC 13881 S-layer protein. For the protein the name SslA was proposed, which is an abbreviation for “Sporosarcina ureae S-layer protein A”. Several specific features were observed in gene organisation of sslA, which are also characteristic for other S-layer genes. The distance between the -35/-10 region and the ATG initiation codon is unusually long and a 41 bp palindromic sequence is present in the immediate vicinity of the -35/-10 region. Besides, a distant location of the rho-independent transcription terminator, which is 647 bp remote from the stop codon, will result in the mRNA transcripts with unusually long trailer region. Both the long 5’ UTR and the long 3’ trailer may have a regulatory function, either by conferring increased mRNA stability and/or by affecting translation efficiency. Potentially these sequences may define the binding sites of regulatory proteins. For example, palindromic sequences constitute the regulatory sites in several bacterial operons and may act as the binding sites of regulatory dimeric proteins. In respect to the conservation of the sslA sequence high similarity to the sequences of other functional S-layer genes, especially the slfA and slfB genes of B. sphaericus, was observed, whereas the results of phylogenetic analysis support the hypothesis that S-layer genes may have evolved via the lateral gene transfer. Based on the sslA sequence, several recombinant proteins with truncations of the terminal protein parts or C-terminal fusion of either EGFP or histidine tags were constructed. For all the truncated or EGFP-fusion SslA derivatives high level overexpression in E. coli was possible. For native SslA a moderate level of expression was observed suggesting that its high intracellular concentration may downregulate the protein synthesis. Interestingly, fluorescence microscopy indicates the same intracellular localization for heterologously produced recombinant proteins with fusions of EGFP either to the precursor or to the native SslA protein, suggesting that SslA secretion signal is not functional in E. coli. Heterologously produced SslA derivatives with truncations of N-, C- or both N- and C-terminal parts were shown to self- assemble in vitro, although the size of self-assembly structures was different from that observed upon the self-assembly of the native SslA. In the latter case extended self-assembly layers with the size up to 5x10 µm were observed, with a surface area of up to two orders of magnitude higher than that of S-layer patches, routinely isolated from S. ureae surface. Dependent on the applied recrystallization conditions preferential formation of single- or multilayer self-assembly structures was observed.
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Ryzhkov, Pavel. "Bioengineering of S-layers: molecular characterization of the novel S-layer gene sslA of Sporosarcina ureae ATCC 13881 and nanotechnology application of SslA protein derivatives." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A24121.
Full textAbstract:
S-layer proteins of S. ureae ATCC 13881 form on the cell surface an S-layer lattice with p4 square type symmetry and a period of about 13.5 nm. These lattices were shown to be the excellent nanotemplates for deposition of regular metal clusters. The synthesis of the S. ureae S-layer protein is highly efficient, the protein accounts for approximately 10-15 % of the total cell protein content, judged by the SDS-PAGE results. Besides, the S-layer protein production is tightly regulated, since only negligible amounts of S-layer proteins are observed in the medium at different cell growth phases. At the same time, mechanisms of the regulation of S-layer protein synthesis are poorly understood. As several hundreds of S-layer proteins are produced per second during the cell growth, the S-layer gene promoters are among the strongest prokaryotic promoters at all. However, little is known about factors regulating the expression of S-layer genes, furthermore, no experimental identification of other upstream regulatory sequences except for -35/-10 and RBS sequences was presented to our knowledge to date. A sequence of the S-layer gene of S. ureae ATCC 13881, encoding the previously described S-layer protein, was identified in this work by combination of different approaches. The largest part of the gene, excluding its upstream regulatory and ORF 5’ regions, was isolated from a genomic library by hybridization. The sequence of the isolated fragment proved to contain additionally an 1.9 kb non-coding region and an incomplete 0.8 kb ORF region in its 3’-part. No RBS sequence and apparent promoter regions could be identified in front of the latter sequence, suggesting that it might represent a pseudogene sequence. The sequences of the 5’ and upstream regions of the S. ureae ATCC 13881 S-layer gene were identified by combination of PCR-sequencing and chromosome walking. Totally, a sequence of the 6.4 kb long region of S. ureae genomic DNA was established. The sequence of the S. ureae S-layer protein was deduced from the respective gene sequence and agreed with the peptide sequences, obtained after N-terminal sequencing of tryptic peptides of the S. ureae ATCC 13881 S-layer protein. For the protein the name SslA was proposed, which is an abbreviation for “Sporosarcina ureae S-layer protein A”. Several specific features were observed in gene organisation of sslA, which are also characteristic for other S-layer genes. The distance between the -35/-10 region and the ATG initiation codon is unusually long and a 41 bp palindromic sequence is present in the immediate vicinity of the -35/-10 region. Besides, a distant location of the rho-independent transcription terminator, which is 647 bp remote from the stop codon, will result in the mRNA transcripts with unusually long trailer region. Both the long 5’ UTR and the long 3’ trailer may have a regulatory function, either by conferring increased mRNA stability and/or by affecting translation efficiency. Potentially these sequences may define the binding sites of regulatory proteins. For example, palindromic sequences constitute the regulatory sites in several bacterial operons and may act as the binding sites of regulatory dimeric proteins. In respect to the conservation of the sslA sequence high similarity to the sequences of other functional S-layer genes, especially the slfA and slfB genes of B. sphaericus, was observed, whereas the results of phylogenetic analysis support the hypothesis that S-layer genes may have evolved via the lateral gene transfer. Based on the sslA sequence, several recombinant proteins with truncations of the terminal protein parts or C-terminal fusion of either EGFP or histidine tags were constructed. For all the truncated or EGFP-fusion SslA derivatives high level overexpression in E. coli was possible. For native SslA a moderate level of expression was observed suggesting that its high intracellular concentration may downregulate the protein synthesis. Interestingly, fluorescence microscopy indicates the same intracellular localization for heterologously produced recombinant proteins with fusions of EGFP either to the precursor or to the native SslA protein, suggesting that SslA secretion signal is not functional in E. coli. Heterologously produced SslA derivatives with truncations of N-, C- or both N- and C-terminal parts were shown to self- assemble in vitro, although the size of self-assembly structures was different from that observed upon the self-assembly of the native SslA. In the latter case extended self-assembly layers with the size up to 5x10 µm were observed, with a surface area of up to two orders of magnitude higher than that of S-layer patches, routinely isolated from S. ureae surface. Dependent on the applied recrystallization conditions preferential formation of single- or multilayer self-assembly structures was observed.
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Binti, Mohd Najib Norazwana. "Dual mode suspended substrate stripline (SSS) filter." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/20593/.
Full textAbstract:
Evolution of wireless communication systems towards high flexibility, low cost and high efficiency leads to tremendous activity in the area of microwave filters. In an RF front-end of a cellular radio base station, signals are being transmitted and received simultaneously. In the receive band, there are chances of intermodulation products from the power amplifier being fed to the receiver,thus the transmit filter must have a very high level of signal rejection. Furthermore, the transmit filter must also have low passband insertion loss since it impacts the power transmitted and the overall transmit system efficiency. Recently, filters with dual-mode operation were being investigated due to their ability to produce two degenerate modes using a single physical structure; therefore, the size and cost of the filter can be reduced without compromising any figure-of-merits. A dual mode suspended substrate stripline filter is presented in this thesis. These filters enable achieving low insertion loss, high Q, high selectivity and good spurious response. Initially, a dual mode ring resonator structure is investigated using suspended substrate stripline technology. This technology is used due to its advantages which are comparable to microstrip or any other planar transmission lines. The HFSS three dimensional finite element method (FEM) is used to evaluate the resonant frequency, quality factor and the first harmonics. A second order suspended substrate stripline filter was designed with capacitive coupled input and output feeding method. The input and output feed were positioned 90 degree from each other while a notch was used in this filter to couple two degenerate modes which also control the bandwidth of the filter. A high performance Generalized Chebychev filter was designed to meet the stringent electrical requirement in the RF front-end of a cellular radio base station. With this fourth order filter, four finite frequency transmission zeros were achieved due to phase cancellation between two paths which results in high selectivity filter response. Metal tuning screws were added to improve any practical imperfections. Finally an asymmetrical Generalized Chebychev filter was designed with real frequency transmission zeros positioned on one side of the passband. With this design, the aim of achieving higher selectivity filter response above the passband was demonstrated.
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Lindström, Per, and Oscar Pap. "Mapping the current state of SSL/TLS." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138391.
Full textAbstract:
The focus of this thesis is to analyze cryptographic protocol and algorithm usage based on three different data sets where the largest set contains one million websites. Ciphers, algorithms and different versions of cryptographic protocols are described and discussed. Some of the common attacks that make the ciphers or protocols obsolete are also presented and explained. In order to obtain the data sets and analyze them, a web crawler and a prober program were developed. The results from the analysis show that more popular websites have better security compared to the not so popular ones. The results also show that many broken and insecure ciphers and protocols are still very popular today. The thesis discusses the use of old software as a potential reason for why so many websites support weak protocols and ciphers.
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Hutar, Jan. "Detekce a analýza přenosů využívajících protokoly SSL/TLS." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-317032.
Full textAbstract:
This diploma thesis deals with a detection and analysis of secure connections of electro- nic communication through SSL/TLS protocols. The thesis begins with introduction to SSL/TLS protocols. Thereafter, an analysis of messages used to establish secure con- nections using STARTTLS and postal protocols SMTP, POP3, and IMAP was made. Metadata detection and extraction of secured simplex and duplex connections take place using deep packet inspection tools. The tool of choice is the nDPI library from the Ntop project. The library was extended to detect the connections and extract the metadata based on studies and analysis of transmitted messages. Finally, testing is performed on a training data set and a basic analysis of acquired metadata is made.
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Pieri, Naira Caroline Godoy. "Espermatogênese xenogênica pós-transplante de células tronco caninas no testículo de camundongos." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-10052016-120531/.
Full textAbstract:
As células tronco espermatogoniais (SSCs) são caracterizadas pela capacidade de autorrenovação, proliferação e transmissão das informações genéticas. Em caninos a primeira tentativa de xenotransplante não obteve o sucesso da produção de espermatozoides, no entanto, há evidências de que as células testiculares xenogênicas podem ser transplantadas no testículo do animal hospedeiro, e gerar espermatozoides viáveis do doador. Portanto, este estudo tem como objetivo realizar o xenotransplante das células germinativas caninas em camundongos imunosuprimidos, e com isto promover à produção de espermatozoides caninos viáveis, geneticamente modificados. E por meio desta técnica, analisar a eficiência da espermatogênese pós-transplante. Células germinativas testiculares foram caracterizadas, isoladas e cultivadas de cães pré-púberes, por meio de sistemas de cultura de enriquecimento e fatores de crescimento. As células foram transduzidas com um gene repórter GFP e LacZ, e por um vetor lentiviral para indentificar as SSCs nos testículos receptores. As SSCs transduzidas foram transplantadas nos testículos de camundongos (C57BL/6) tratados com Busulfan, após diferentes períodos os animais receptores foram eutanasiados e analisados. Aos 10 dias de cultivo as células germinativas adultas foram positivas para CD49f, CD117, e com 5 dias uma expressão semelhante de GFRA1 e DAZL, demonstrando a presença de SSCs e algumas células em meiose. Transplantamos 105 células e 20-43% das células transplantadas foram identificadas na membrana basal dos túbulos seminíferos do animal receptor. Portanto, o transplante das células germinativas caninas, mostrou que a purificação e o cultivo realizados são possíveis para obter SSCs caninas, as quais colonizaram os túbulos seminíferos dos camundongos imunodeficientes e mantiveram-se vivas na membrana basal por 90 dias após transplante, mesmo que estes animais tenham distância filogenética<br>The spermatogonial stem cells (SSCs) are characterized by the capacity for self-renewal, proliferation and transmission of genetic information. In canines the first attempt to xenotransplantation did not achieve the success of sperm production. However, there is evidence that testicular xenogeneic cells can be transplanted into the testis of the host animal, and generate viable sperm donor. Therefore, this study aims conduct xenotransplantation of the canine germ cells in immunosuppressed mice, and thereby promote the production of viable sperm canines, genetically modified. And by this technique, analyze the efficiency of post-transplant spermatogenesis. Testicular germ cells were identified, isolated and cultured prepuberes dogs through enrichment culture systems and growth factors. Cells were modificated with a reporter gene GFP and LacZ. The SSCs canine was transplanted in mice (C57Bl/6), after different period and then the recipient animals were euthanized and analyzed. After 10 days in culture the germ cells were positive for CD49f, CD117, and 5 days a similar expression of GFRA1 and DAZL was observed, demonstrating the presence of SSCs and some cells in meiosis. 105 cells were transplanted and 20-43% of the transplanted cells were identified in the basement membrane of the seminiferous tubules after 90 days after transplantation. Therefore, the transplantation of canine germ cells showed that the cultivation and purification are performed possible for canine SSCs, it can colonize the seminiferous tubules the mice infertility remained alive in the basement membrane for 90 days after transplanting, even though these animals have phylogenetic distance
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Zhang, Jin. "Immunological modulation of antioxidants in side-stream cigarette smoke (SSCS) exposed mice." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280048.
Full textAbstract:
Environmental tobacco smoke (ETS) is a complex mixture of chemicals generated during the burning of tobacco products. The principle contributor to ETS is side-stream cigarette smoke (SSCS), the material emitted from the smoldering tobacco product between puffs Our hypothesis is that reactive oxygen species from SSCS are playing an essential role in disease promotion and antioxidant supplementation (a single form of alpha-tocopherol or a mixture of multiple antioxidants) will potentially prevent SSCS associated tissue damage, pulmonary dysfunction. The specific aims of the present study are to determine if: (1) SSCS would induce tissue lipid peroxidation and proinflammatory responses; (2) SSCS would provoke pulmonary and cardiac function changes; (3) SSCS would cause oxidative stress, reduce nutrient concentrations and suppress immune function in murine retrovirus infections; (4) dietary alpha-tocopherol, specifically, can enhance resistance to oxidative damage by SSCS and improve lung function; (5) multiple antioxidant supplementation can modulate proinflammatory cytokine secretion and tissue lipid peroxidation induced by SSCS exposure in old healthy mice. SSCS exposure methodology in a murine model was developed to facilitate these goals. For the first time we established a SSCS model in murine retrovirus infection. Also we conduced a SSCS dose-response model for a cardiac function study. We found that SSCS exposure in mice consistently increased oxidation, depleted tissue vitamin E levels, and promoted inflammatory cytokines production. SSCS exposure at 120-min/day, 5 days/week for 12 weeks decreased heart contractile function and increased vascular resistance. SSCS induced increased oxidative stress, reduced nutrient concentrations and suppressed immune function, which could make mice with murine retrovirus more susceptible to opportunistic infections. Dietary alpha-tocopherol enhanced resistance against SSCS-induced oxidation and improved lung function, primarily through the antioxidant property of alpha-tocopherol and its modulation of local cytokine production. The multiple antioxidant with beta-carotene, bioflavanoids, Coenzyme Q10, d-alpha-tocopherol, L-ascorbic acid, L-carnitine, magnesium, N-acetylcysteine, retinol, selenium and zinc given as a dietary supplementation prevented oxidation and IL-6 production in healthy old mice during SSCS exposure. (Abstract shortened by UMI.)
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Lokaj, Lukáš. "Analýza správy podnikových dokumentů v SSČS a.s. a návrh na její optimalizaci." Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-199591.
Full textAbstract:
This thesis focuses on design of document exchange solution used between Stavební spořitelna České spořitelny a.s. (SSČS) and its external sales network, which is outdated and doesn't meet the needs of SSČS or sales network. The thesis also includes the identification of suitable basic principles used in the service-oriented architecture (SOA) concept and their application in design solutions. The aim of the thesis is a conceptual solution design, based on the principles of SOA and the following technological design of changes in existing environment, so that on this basis could be created a functional and technical specification for suppliers of these applications. Stated objective is achieved through an initial analysis of the current environment, which identifies the possibilities of existing applications, and identifies weaknesses in the process that will be changed in the new solution. The analysis covers as the environment of external sales network as the related environment in SSČS, which together figure in the process of documentation exchange. As the results of the analysis and based on theoretical knowledge and consultation with experts in the field of SOA is then formulated a proposed solution at the conceptual level, which is further elaborated in the description of the proposed changes in individual components of the new solution. The outputs of this thesis will serve SSČS both in terms of describing the existing and the new environment, and as an input for the specifications of the proposed amendments to the supplier concerned applications. Structure of the thesis consists of introduction, devoted to the characterization of SSČS and providing an initial framework for solved domain. This is followed by a description and the analysis of external sales network, particularly in terms of application equipment and communication flows, followed by a description of the environment in SSČS, which contains the components processing sent documents. Next part of thesis is devoted to the formulation of the basic concepts of SOA and selection of appropriate principles that are followed in the subsequent section to draft the solution itself, first at the conceptual level, followed by a detailed description of the necessary changes. Everything is then evaluated in the final part.
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Xiang, Jianwei. "Stochastic Estimation of Hydraulic Spatial Properties." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/195209.
Full textAbstract:
A tomographic survey provides different coverages and perspectives on subsurface heterogeneity--incompletely overlapping information about the subsurface. Fusion of these pieces of information expands and enhances the capability of a conventional survey, provides cross-validation, and constrains inherently ill-posed field-scale inverse problems. In this study, we explore the possibility of using river stage variation for basin-scale subsurface tomographic surveys. Basin-scale tomography requires energy sources of great strengths; spatially and temporally varying natural stimuli are ideal energy sources for this purpose. Specifically, we use numerical models to simulate groundwater level changes in response to temporal and spatial variations of river stage in a hypothetical groundwater basin. We then exploit the relation between temporal and spatial variations of well hydrographs and river stage to image the heterogeneous characteristics of the basin.Next, we apply the hydraulic tomography testing technique and analysis algorithm to synthetic fractured media. The application aims to explore the potential utility of the technique and the algorithm for characterizing fracture zone distribution and their connectivity. Results of this investigation show that using hydraulic tomography with a limited number of wells can map satisfactorily the fracture zone distribution and the general pattern of its connectivity although estimated hydraulic property fields are smooth. As the number of wells and monitoring ports increases, the fracture zone distribution and connectivity becomes more vivid and the estimated hydraulic properties approach the true values.Further we develop a new parameter identification method that allows for simultaneous inclusion of all observed hydrographs from hydraulic tomography to map aquifer heterogeneity. A procedure is then recommended to diagnose and denoise observed hydrographs. Subsequently, we introduce methods that exploit these processed hydrographs for estimating effective parameters, boundary conditions, and statistical spatial structures of heterogeneity, which are the required inputs for the new hydraulic tomography analysis method. This new method and the data processing procedure are tested in a synthetic aquifer and subsequently applied to a sand box experiment. The estimated parameter fields for the sand box experiment are validated by predicting the head distribution induced by an independent pumping test, which was not used in the hydraulic tomography analysis.
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Holtzhausen, David Schalk. "Development of distributed control system for SSL soccer robots." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80221.
Full textAbstract:
Thesis (MScEng)--Stellenbosch University, 2013.<br>ENGLISH ABSTRACT: This thesis describes the development of a distributed control system for SSL
soccer robots. The project continues on work done to develop a robotics research
platform at Stellenbosch University. The wireless communication system
is implemented using Player middleware. This enables high level programming
of the robot drivers and communication clients, resulting in an easily
modifiable system. The system is developed to be used as either a centralised
or decentralised control system. The software of the robot’s motor controller
unit is updated to ensure optimal movement. Slippage of the robot’s wheels
restricts the robot’s movement capabilities. Trajectory tracking software is developed
to ensure that the robot follows the desired trajectory while operating
within its physical limits.
The distributed control architecture reduces the robots dependency on the
wireless network and the off-field computer. The robots are given some autonomy
by integrating the navigation and control on the robot self. Kalman filters
are designed to estimate the robots translational and rotational velocities. The
Kalman filters fuse vision data from an overhead vision system with inertial
measurements of an on-board IMU. This ensures reliable and accurate position,
orientation and velocity information on the robot. Test results show an
improvement in the controller performance as a result of the proposed system.<br>AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die ontwikkeling van ’n verspreidebeheerstelsel vir SSL
sokker robotte. Die projek gaan voort op vorige werk wat gedoen is om ’n
robotika navorsingsplatform aan die Universiteit van Stellenbosch te ontwikkel.
Die kommunikasiestelsel is geïmplementeer met behulp van Player middelware.
Dit stel die robotbeheerders en kommunikasiekliënte in staat om in hoë vlak
tale geprogrameer te word. Dit lei tot ’n maklik veranderbare stelsel. Die
stelsel is so ontwikkel dat dit gebruik kan word as óf ’n gesentraliseerde of verspreidebeheerstelsel.
Die sagteware van die motorbeheer eenheid is opgedateer
om optimale robot beweging te verseker. As die robot se wiele gly beperk dit
die robot se bewegingsvermoëns. Trajekvolgings sagteware is ontwikkel om
te verseker dat die robot die gewenste pad volg, terwyl dit binne sy fisiese
operasionele grense bly.
Die verspreibeheerargitektuur verminder die robot se afhanklikheid op die
kommunikasienetwerk en die sentrale rekenaar. Die robot is ’n mate van outonomie
gegee deur die integrasie van die navigasie en beheer op die robot self te
doen. Kalman filters is ontwerp om die robot se translasie en rotasie snelhede
te beraam. Die Kalman filters kombineer visuele data van ’n oorhoofse visiestelsel
met inertia metings van ’n IMU op die robot. Dit verseker betroubare
en akkurate posisie, oriëntasie en snelheids inligting. Toetsresultate toon ’n
verbetering in die beheervermoë as ’n gevolg van die voorgestelde stelsel.
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Lesniewski-Laas, Christopher T. (Christopher Tur) 1980. "SSL splitting and barnraising : cooperative caching with authenticity guarantees." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/16981.
Full textAbstract:
Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.<br>Includes bibliographical references (p. 35-37).<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>SSL splitting is a cryptographic technique to guarantee that public data served by caching Web proxies is endorsed by the originating server. When a client makes a request, the trusted server generates a stream of authentication records and sends them to the untrusted proxy, which combines them with a stream of data records retrieved from its local cache. The combined stream is relayed to the client, a standard Web browser, which verifies the data's integrity. Since the combined stream simulates a normal Secure Sockets Layer (SSL) [7] connection, SSL splitting works with unmodified browsers; however, since it does not provide confidentiality, it is appropriate for applications that require only authentication. The server must be linked to a patched version of the industry-standard OpenSSL library; no other server modifications are necessary. In experiments replaying two-hour access.log traces taken from LCS Web sites over a DSL link, SSL splitting reduces bandwidth consumption of the server by between 25% and 90% depending on the warmth of the cache and the redundancy of the trace. Uncached requests forwarded through the proxy exhibit latencies within approximately 5% of those of an unmodified SSL server.<br>by Christopher T. Lesniewski-Laas.<br>M.Eng.
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Meihong, Li, Zhang Qishan, and Wang Jun. "RESEARCH AND IMPLEMENTATION OF MOBILE BANK BASED ON SSL." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/605837.
Full textAbstract:
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>SSL protocol is one industrial standard to protect data transferred securely on Internet. Firstly SSL is analyzed, according to its characteristics, one solution plan on mobile bank based on SSL is proposed and presented, in which GPRS technology is adopted and elliptic curve algorithm is used for the session key, finally several functional modules of mobile bank are designed in details and its security is analyzed.
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Menon, Smita Kesavankutty. "X-ray crystallographic studies of the proteins from sulfolobus spindle-shaped viruses (SSVs)." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/menon/MenonS0809.pdf.
Full textAbstract:
Viruses populate virtually every ecosystem on the planet. Fuselloviridae are ubiquitous crenarchaeal viruses found in high-temperature acidic hot springs around the world. However, compared to eukaryotic and bacterial viruses, our knowledge of viruses infecting the archaea is limited. Fuselloviral genomes show little similarity to other organisms, generally precluding functional predictions. However, structural studies can reveal distant evolutionary relationships and provide functional insights that are not apparent from the primary amino acid sequence alone. Several such structural studies have already contributed to our understanding of the Sulfolobus Spindle-shaped viruses (Fuselloviridae). Here we report the structure of two proteins, SSV1 F112 and SSVRH D212. Biochemical, proteomic and structural studies of F112 reveal a monomeric intracellular protein that adopts a winged helix DNA binding fold. Continuing these efforts, a second structure was also determined where the overall fold and conservation of active site residues place D212 within the PD-(D/E)XK nuclease superfamily. Notably, the structure of F112 contains an intrachain disulfide bond, prompting analysis of cysteine usage in this and other hyperthermophilic viral genomes. The analysis supports a general abundance of disulfide bonds in the intracellular proteins of hyperthermophilic viruses and the evolutionary implications of such distribution are discussed. Here we review and describe our progress towards understanding these viruses at a molecular level.
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Britton, Warner H. Eaves Ronald C. "The Sensation Seeker Attention Scale (SSAS) a measure of sensation seeking by adolescents /." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Fall%20Dissertations/Britton_Warner_10.pdf.
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Polato, Ivanilton. "Energy savings and performance improvements with SSDs in the Hadoop Distributed File System." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-31102016-155908/.
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Energy issues gathered strong attention over the past decade, reaching IT data processing infrastructures. Now, they need to cope with such responsibility, adjusting existing platforms to reach acceptable performance while promoting energy consumption reduction. As the de facto platform for Big Data, Apache Hadoop has evolved significantly over the last years, with more than 60 releases bringing new features. By implementing the MapReduce programming paradigm and leveraging HDFS, its distributed file system, Hadoop has become a reliable and fault tolerant middleware for parallel and distributed computing over large datasets. Nevertheless, Hadoop may struggle under certain workloads, resulting in poor performance and high energy consumption. Users increasingly demand that high performance computing solutions address sustainability and limit energy consumption. In this thesis, we introduce HDFSH, a hybrid storage mechanism for HDFS, which uses a combination of Hard Disks and Solid-State Disks to achieve higher performance while saving power in Hadoop computations. HDFSH brings, to the middleware, the best from HDs (affordable cost per GB and high storage capacity) and SSDs (high throughput and low energy consumption) in a configurable fashion, using dedicated storage zones for each storage device type. We implemented our mechanism as a block placement policy for HDFS, and assessed it over six recent releases of Hadoop with different architectural properties. Results indicate that our approach increases overall job performance while decreasing the energy consumption under most hybrid configurations evaluated. Our results also showed that, in many cases, storing only part of the data in SSDs results in significant energy savings and execution speedups<br>Ao longo da última década, questões energéticas atraíram forte atenção da sociedade, chegando às infraestruturas de TI para processamento de dados. Agora, essas infraestruturas devem se ajustar a essa responsabilidade, adequando plataformas existentes para alcançar desempenho aceitável enquanto promovem a redução no consumo de energia. Considerado um padrão para o processamento de Big Data, o Apache Hadoop tem evoluído significativamente ao longo dos últimos anos, com mais de 60 versões lançadas. Implementando o paradigma de programação MapReduce juntamente com o HDFS, seu sistema de arquivos distribuídos, o Hadoop tornou-se um middleware tolerante a falhas e confiável para a computação paralela e distribuída para grandes conjuntos de dados. No entanto, o Hadoop pode perder desempenho com determinadas cargas de trabalho, resultando em elevado consumo de energia. Cada vez mais, usuários exigem que a sustentabilidade e o consumo de energia controlado sejam parte intrínseca de soluções de computação de alto desempenho. Nesta tese, apresentamos o HDFSH, um sistema de armazenamento híbrido para o HDFS, que usa uma combinação de discos rígidos e discos de estado sólido para alcançar maior desempenho, promovendo economia de energia em aplicações usando Hadoop. O HDFSH traz ao middleware o melhor dos HDs (custo acessível por GB e grande capacidade de armazenamento) e SSDs (alto desempenho e baixo consumo de energia) de forma configurável, usando zonas de armazenamento dedicadas para cada dispositivo de armazenamento. Implementamos nosso mecanismo como uma política de alocação de blocos para o HDFS e o avaliamos em seis versões recentes do Hadoop com diferentes arquiteturas de software. Os resultados indicam que nossa abordagem aumenta o desempenho geral das aplicações, enquanto diminui o consumo de energia na maioria das configurações híbridas avaliadas. Os resultados também mostram que, em muitos casos, armazenar apenas uma parte dos dados em SSDs resulta em economia significativa de energia e aumento na velocidade de execução
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Tarnowski, Christian Gabriel. "Desenvolvimento e caracterização de marcadores microssatélites (SSRs) para Cedrela Lilloi C. de Candolle." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/94114.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Recursos Genéticos Vegetais, Florianópolis, 2010<br>Made available in DSpace on 2012-10-25T06:44:29Z (GMT). No. of bitstreams: 1
287627.pdf: 1226059 bytes, checksum: 2337976f95da6827275c91baaf2701fc (MD5)<br>Cedrela lilloi (Meliaceae) é uma das quatro espécies de cedro nativas da Argentina e encontra-se estritamente distribuída na Selva de Yungas na região noroeste do país. Como tantas outras espécies florestais de importância econômica, as populações de C. lilloi encontram-se vulneráveis a exploração e fragmentação. No país são escassos os estudos referentes à diversidade e estrutura genética destas populações. Assim, os objetivos principais deste estudo foram a) desenvolver marcadores microssatélites específicos para a espécie e, b) estimar a variabilidade genética de três populações naturais. O DNA genômico de C. lilloi foi digerido com enzima, purificado, enriquecido através de sondas de oligos CT(8), GT(8) e TTC(8), clonado em bactérias e finalmente isolado e sequenciado. Dos 258 clones sequenciados, a porcentagem total de sequências microssatélites observadas foi muito baixa (14%). Foram desenhados iniciadores para essas 37 regiões microssatélites encontradas e somente quatro locos amplificaram produtos polimórficos. Devido a que os poucos locos desenvolvidos não foram suficientes para analisar as populações, foi considerado a alternativa da transferibilidade. Foram transferidos cinco iniciadores provenientes de outras espécies da família Meliaceae. No total, foram utilizados oito locos, três próprios de C. lilloi e cinco transferidos (média de 5,25 alelos), para analisar três populações com um total de 140 indivíduos. Nenhum loco apresentou desequilíbrio de ligação e não foi observada a presença de alelos nulos. A heterozigosidade observada (Ho) total foi de 0,406 e a esperada (He) de 0,416. O índice de fixação dentro das populações (FIS=0,035) não foi estatisticamente diferente de zero, indicando que a probabilidade de acasalamento entre indivíduos aparentados não é diferente do esperado no equilíbrio de Hardy-Weinberg. A endogamia a nível grupal (FIT=0,140) e a diferenciação genética entre as populações foram iguais e moderadas (FST=0,108), indicando que as populações estão estruturadas por causa da perda de alelos devido à deriva genética. As duas populações da região norte das Yungas (Baritú e San Andrés) foram geneticamente mais similares entre si e apresentaram maior diversidade gênica em comparação a população amostrada na região sul (El Siambón).
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Schmidt, Andréa Branco. "Desenvolvimento e caracterização de marcadores microssatélites (SSRs) para Araucaria angustifolia (Bert.) O. Kuntze." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/103108.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias. Programa de Pós-Graduação em Recursos Genéticos Vegetais.<br>Made available in DSpace on 2013-07-16T02:57:05Z (GMT). No. of bitstreams: 0<br>Este trabalho apresenta os resultados do desenvolvimento e caracterização de marcadores microssatélites para Araucaria angustifolia a partir de bibliotecas genômicas enriquecidas para seqüências microssatélites (SSR). O trabalho envolveu clonagem de segmentos genômicos, transformação bacteriana, sequenciamento de clones, desenho de iniciadores específicos e otimização de marcadores. A triagem dos iniciadores foi feita utilizando-se inicialmente quatro indivíduos em gel de agarose 2%. Para a otimização foram utilizados 16 indivíduos de 5 diferentes populações em gel de poliacrilamida 4%, com detecção em nitrato de prata. Foram obtidos 29 marcadores microssatélites inéditos para Araucaria angustifolia, com a possibilidade de utilização imediata. Os marcadores desenvolvidos revelaram elevada heterozigosidade esperada para os locos, com uma detecção média de 8,1 alelos por loco. Os marcadores microssatélites demonstraram elevado conteúdo informativo para os estudos de diversidade genética e discriminação genotípica de indivíduos. As sequências originais contendo regiões microssatélites foram depositadas no GenBank (NCBI - National Center for Biotechnology Information). Um estudo de diversidade genética e estrutura de duas populações naturais de Araucaria angustifolia foi desenvolvido utilizando-se locos microssatélites específicos desenvolvidos para a espécie. Para realizar a genotipagem das duas populações: Guamirim Gateado e Parque Ecológico de Lages, foram utilizados dois sistemas de detecção alélica colorimétrico baseado em nitrato de prata, aplicado a sete locos microssatélites e outro com detecção por fluorescência aplicado a nove locos microssatélites. Os resultados mostram que, grande parte da variabilidade genética observada nas duas populações encontra-se dentro das populações e não entre as populações. As análises feitas a partir de genotipagens em sistema com nitrato de prata, superestimaram os valores de heterozigosidade. O sistema de detecção fluorescente mostrou-se necessário quando os marcadores microssatélites são baseados em seqüências de di-nucleotídeo, pois facilitam a análise em sistema "multiplex" utilizados na mesma reação de amplificação e/ou analisados conjuntamente na mesma eletroforese, propiciando redução de gastos e maior confiabilidade nos resultados devido à leitura automática do sistema, baseado no marcador de tamanho de fragmento conhecido. As comparações das análises populacionais feitas nos distintos sistemas de detecção revelaram que o sistema de detecção com fluorescência, é significativamente mais preciso devido à presença de bandas fantasmas, formadas pela separação das duas fitas de DNA durante a eletroforese, detectadas nas análises com nitrato de prata. Diferenças estatisticamente significativas entre os valores de heterozigosidade das duas populações estudadas foram obtidas com marcadores isoenzimáticos, fato este que não foi confirmado com o uso de marcadores microssatélites (0,87 e 0,86 para He e de 0,59 e 0,58 para Ho, respectivamente). Marcadores isoenzimáticos revelaram diferença estatística na estrutura genética entre as duas populações. No estudo com marcadores microssatélites não foi detectada divergência significativa entre as duas populações estudadas (FST=0,023).
(Instituição financiadora: FAO - Food and Agriculture Organization of the United Nations/Ministério do Meio Ambiente).
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Malhotra, Vasudha. "Teachers' perspectives on teaching of socio-scientific issues (SSIs) in Indian science classrooms." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15428/.
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This thesis explores the teachers’ perspectives on the teaching of Socio-Scientific Issues (SSIs) and the factors that influence their teaching. SSIs are those contemporary issues that are deep rooted in sciences, have an impact on society, involve moral and ethical reasoning and are controversial in nature. The study has been conducted in the context of Indian science classrooms, with fourteen upper primary and secondary stage science teachers from five schools. Three of the five selected schools are Green Schools, which have an explicit focus on the teaching of environmental SSIs. The data was collected using semi-structured interviews and classroom observation sessions, with a focus on following two questions. (1) What are the methods and strategies used by the teachers for teaching SSIs? (2) What are the factors that influence the teaching of SSIs? The results showed that the majority of teachers supported the teaching of SSIs and for some this links to specific SSIs in their lives and local communities in their Indian context, particularly pollution and environmental threats. However, a significant level of variation was witnessed in their actual classroom practices for teaching SSIs. The various profiles of teachers, classified based on their beliefs and classroom practices, have been discussed. Among the methods used by the teachers for teaching SSIs, the two most common method for teaching SSIs were discussions and lecture method. Four different forms of discussions and two different forms of lecture method have been delineated based on the strategies used by the teachers for teaching SSIs. Results indicated that teachers’ beliefs, school leadership and assessment system are the most influential factors for SSIs teaching. Implications and the major findings of this research have been discussed which contribute towards the acute lack of empirical studies over the teaching of SSIs in Indian schools.
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Jeschke, Jonathan Michael. "Funktionelle Reaktionen von Konsumenten: die SSS Gleichung und ihre Anwendung." Diss., lmu, 2002. http://nbn-resolving.de/urn:nbn:de:bvb:19-5159.
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Nunga, Jude, and Godwin Okeke. "Investigating Security Options for StudentDevelop.com and the Testing of SSL." Thesis, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), School of Information Science, Computer and Electrical Engineering (IDE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-18970.
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Security issues have become a key problem with most e-commerce platforms these days and information sent over the internet needs to be protected. When operating an e-commerce platform such as studentdevelop.com financial transactions are involved. Data communication is very vital to e-commerce and needs to be processed securely. This thesis shall investigate Secure Socket Layer (SSL) as a possible solution to provide added security such as data integrity and confidentiality on the StudentDevelop.com web portal. This thesis shall also compare other known security suites available for use which could suit the StudentDevelop.com web platform. A vivid comparison shall be carried out to evaluate SSL and Pretty Good Privacy (PGP) with the aim of testing the preferred choice to provide encryption and data confidentiality on the StudentDevelop.com platform. Protocols like SSL make up the next layers of mechanisms that support applications with electronic payment schemes. Cryptography being an essential security technology involving the encryption algorithm and digital signatures can provide the basic building blocks. SSL shall be tested on the StudentDevelop.com platform by installing a self-signed certificate, including a test of a digital certificate obtained from a certificate authority. In SSL, the web browser is the client and the web-site server is the server. As a result to authenticate consumers on e-commerce platform such as studentdevelop.com, SSL increased the security for web transactions by using public-key encryption and digital certificate to achieve authentication. Encryption algorithm and digital signatures provided the basic building blocks, while SSL protocol made up the next layer of mechanisms that in return support the application layer. In the fourth coming sub chapters, we will look in to the problem description of this thesis and the investigation of security solutions for studentdevelop.com.
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Jeschke, Jonathan M. "Funktionelle Reaktionen von Konsumenten die SSS-Gleichung und ihre Anwendung /." [S.l.] : [s.n.], 2002. http://edoc.ub.uni-muenchen.de/archive/00000515.
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Svensson, Pär. "Upgrading the SSL protocol to TLS in the Roxen WebServer." Thesis, Linköping University, Department of Electrical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1475.
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<p>The company Roxen Internet Software have an implementation of the secure network protocol SSL (Secure Sockets Layer) which is used in their web server product. This report describes the upgrading of that implementation to the TLS1.0 (Transport Layer Security) standard. It also describes a performance investigation of the SSL/TLS support in the Roxen WebServer and compares it with other common web servers. The initial setup time for the secure SSL/TLS connection was found to be very long in the Roxen Webserver compared to its competitors. The main bottleneck, in the Roxen implementation, was found to be the modular exponentiation that is the core of the RSA decryption algorithm. One suggested improvement is to upgrade the bignumber numerical package used in Roxen WebServer, GMP (The GNU Multiple Precision arithmetic library) from version 2.0 to version 4.0. The newer version of the bignumber package have been measured to have considerably better performance in its modular exponentation operation.</p>
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Kauschke, Christina. "Frühe lexikalische Verzögerung als Indikator für SSES? : Neue Befunde zur Entwicklung von Late Talkern." Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/1890/.
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Auszug:
Seit langem ist bekannt, dass Kinder mit Sprachentwicklungsstörungen meist schon in einem frühen Stadium ihrer Sprachentwicklung auffallen: die ersten Wörter werden verspätet produziert, der Wortschatz wächst langsamer an, der Vokabularspurt setzt verzögert ein oder bleibt aus, so dass das produktive Vokabular mit zwei Jahren weniger als 50 Wörter umfasst. Außerdem treten keine Wortkombinationen auf. Obwohl bei nahezu jeder Sprachentwicklungs-störung retrospektiv derartige frühe Anzeichen auszumachen sind, mündet andererseits nicht jede frühe Verzögerung in eine anhaltende Störung. Diese Beobachtung hat Anlass zu einer regen Forschungstätigkeit gegeben. Im Zentrum steht die Frage, anhand welcher Kriterien sich der weitere Entwicklungsverlauf eines sprachlich verzögerten Kindes prognostizieren lässt. Der Forschungsstand zu diesem Bereich wurde an anderer Stelle bereits ausführlich beschrieben (z. B. in Kauschke 2000, 2003, 2006a). In diesem Beitrag möchte ich die Entwicklungswege dieser Population anhand aktueller Studien skizzieren, die Problematik der Prädiktion ansprechen und eine Studie über Sprachentwicklungsverläufe im dritten Lebensjahr vorstellen, in der ungestörte Kinder und sprachlich verzögerte längsschnittlich beobachtet wurden. Es folgen Überlegungen zur Therapienotwendigkeit und Therapiekonzeption, die durch die Darstellung eines exemplarischen Therapieverlaufs bei einem Einzelfall illustriert werden. [...]
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Bashir, Muhammad Shahid, and Mohd Zalmy Zakaria. "Hesitation on adoption Self-Service Technologies (SSTs) : A case study on self payment machine." Thesis, Umeå University, Department of Informatics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34814.
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<p><em>Self service providers are making such systems which offer faster and more flexible service to the user. Most of us are familiar about self service technologies such as Kiosk, Auto Teller Machine, Self Check in machine, Self payment machine etc. Unfortunately, users are not using these SSTs commonly as advancement has been occurring in SSTs. Sometimes, people look annoyed and feel fear to use such kind of technology at public spaces. Generally, these systems need interaction between users and technology to create service outcome instead of interacting with a service personnel. These technological interfaces have been called Self-service technologies (SSTs). Yet, not all users choose to use the new technologies and they still feel some hesitations to adopt this technologies in this case SSTs. This study investigated the factors that make users hesitate to use and adopt SSTs.</em></p>
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Lokusethu, Hewage Don Danuska Hasitha. "TBM tunnelling through unfavourable ground conditions : a case study, SSDS tunnel F, Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/192957.
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A study of the Strategic Sewage Disposal Scheme (SSDS) Stage 1 Tunnel F in Hong Kong was carried out as it is a great example of deep sub-sea hard rock TBM tunnelling through unfavourable, fault-affected ground conditions with heavy water inflows. The main objective of this study was to document events that took place during Tunnel F excavation and collate geological and geotechnical data related to the excavation, to aid future tunnel designers and contractors to assess the risk involved with such tunnelling projects. Data relevant to Tunnel F was collected from many personnel involved with the excavation, and from the Hong Kong Geological Survey (HKGS) of the Geotechnical Engineering Office. Geological maps, ground investigation data, tunnel mapping records, ground water inflow records and grouting records were reviewed and used to summarise the ground conditions and to analyse various potential relationships.
Knowledge of ground conditions is the most important requirement for any tunnelling project. This dissertation addresses the differences between actual and predicted ground conditions and the consequences of lack of ground investigation data. The major difference between predicted and observed ground conditions during Tunnel F excavation was the amount of water ingress into the tunnel. Hundreds of liters per minute of water at up to 13bar pressure was encountered from a few probe and grout holes. In the Tolo Channel Fault area, low Q values and very high ground water inflows were experienced, and heavy temporary support and large grout volumes were required to complete the tunnel.<br>published_or_final_version<br>Applied Geosciences<br>Master<br>Master of Science
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Drogat, Julie. "Rôle des protéines Ssl3 et Ssl38 dans la transmission des chromosomes chez Schizosaccharomyces Pompe." Bordeaux 2, 2007. http://www.theses.fr/2007BOR21497.
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La transmission fidèle des chromosomes lors des divisions mitotiques est essentielle à la stabilité du génome. En début de mitose, les chromosomes préalablement dupliqués en phase S condensent sous la forme de deux chromatides soeurs associées et les centromètres capturent les microtubulures du fuseau. Lors de la transition métaphase-anaphase, la cohésion des chromatides soeurs est éliminée, déclenchant leur migration vers les pôles opposés du fuseau. La cohésion est assurée par le complexe cohésine, chargé sur les chromosomes en phase G1 du cycle cellulaire et maintenu jusqu'en anaphase. Les mécanismes par lesquels les cohésines s'associent aux chromosomes et assurent la cohésion sont mal compris. Les centromères sont généralement constitués d'hétérochromatine, une forme compacte de la chromatine, dont l'assemblage fait intervenir la machinerie de RNAi. Des mutations affectant certains composants structuraux de l'hétérochromatine, comme Swi6/HP1 chez Saccharomyces pombe, altèrent la ségrégation des chromosomes en mitose. Afin d'appréhender les rôles de Swi6, ses partenaires fonctionnels ont été recherchés par un crible génétique. Ici, je présente l'étude des gènes ss13 et ss138 (swi6 synthétique létal). Le gène ss13 code un facteur de chargement des cohésines en phase G1 du cycle cellulaire, dont la fonction est conservée au cours de l'évolution. Etonnament, ss138 code un composant du spliceosome. Les résultats présentés montrent que Ss138 est nécessaire à l'intégrité de l'hétérochromatine centromérique. La signification biologique du lien entre Ss138, la maturation des ARNs, et l'assemblage de l'hétérochromatine centrométrique est discutée<br>In all eukaryotes, the genome stability relies on accurate chromosome segregation throughout mitotic divisions. During early mitosis, each duplicated chromosomes condense into a pair of tightly linked sister chromatids and centromeres capture spindle microtubules. At the metaphase to anaphase transition, cohesion between sister chromatids is removed, triggering their migration towards the opposite spindle poles. Sister chromatid cohesion is ensured by cohesin, a proteinaceous complex loaded onto chromosomes in G1 and maitained chromosomally bound until anaphase onset. The mechanisms through which cohesin is loaded onto chromosomes and ensures cohesion are ill defined. In most eukaryotes, centromeres are made of heterochromatin : a specialized form of chromatin whose assembly and maintenance rely on the RNAi pathway. Mutations affecting structural components of heterochromatin, such as Swi6/HP1 in fission yeast, impair chromosome segregation. In order to investigate the biological functions of Swi6, its functional partners were sought through a genetic screen. Here I report on the study of ss13 and ss138 (swi6 synthetic lethal). The ss13 gene encodes a cohesin loading factor, whose function in G1 in evolutionarily conserved. Unexpectedly, ss138 encodes a spliceosome component. Experimental data indicate that ss138 is essential for centrometric heterochromatin integrity and accurate chromosome segregation. The biological significance of a link between Ss138, RNA modifications and the assembly of centrometric heterochromatin is discussed
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Vignudelli, Andrea. "Filtraggio e censura dei servizi Internet Un'analisi sul protocollo SSL/TLS." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13204/.
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Obiettivo ultimo di questa tesi è fornire le competenze necessarie per poter capire come effettuare politiche di filtraggio dei contenuti fruibili su Internet in contesti prevalentemente di network locali come LAN aziendali ma anche su scala maggiore, effettuando politiche di blocco al livello logico 7 della pila protocollare ISO/OSI.
Nello specifico verranno approfondite le specifiche tecniche del protocollo SSL/TLS e su queste basi teoriche verranno implementate e testate regole di blocco di specifici servizi Internet simulando il contesto di una piccola rete domestica con un Firewall di frontiera posto davanti al gateway della rete locale che funge da filtro per la comunicazione con la rete Internet.
Verranno inoltre esposte delle problematiche direttamente correlate a quella che è l'infrastruttura giuridica fisicamente costruita intorno all'accertamento dell'identità digitale degli enti/soggetti all'interno di comunicazioni che sfruttano le funzionalità del protocollo SSL/TLS come strumento per criptare i dati ed avere garanzia sull'identità che si cela sul lato Server della comunicazione, trattando nello specifico alcuni casi storici di brecce informatiche all'interno delle infrastrutture fisiche dei Certificate Authorities, enti predisposti al ruolo di certificatori delle identità digitali sopracitate, o dell'uso improprio da parte loro del potere conferitogli, saranno inoltre esposti e replicati su scala minore esempi di come alcuni enti governativi nazionali sfruttano alcune caratteristiche intrinseche di questo protocollo per bloccare determinati servizi all'interno della sottorete Internet da loro gestita e di come in un contesto storico nel quale venisse a mancare il caposaldo della Network Neutrality, proprio quelle specifiche protocollari potrebbero essere utilizzate per effettuare politiche di gestione prioritaria nell'instradamento dei pacchetti all'interno della rete Internet.
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Garin, Etienne. "Développement du 188Re-SSS lipiodol pour le traitement des carcinomes hépatocellulaires." Rennes 1, 2004. http://www.theses.fr/2004REN1B084.
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Nous décrivons une moriginale, simple et reproductible de marquage du lipiodol au technétium 99m et au rhénium 188 pour la radiothérapie métabolique des carcinomes hépatocellulaires. La procédure de marquage repose sur la synthèse d'un complexe lipophile du technétium 99m ou du rhénium 188 (le complexe métal-SSS) secondairement solubilisé dans du lipiodol. Le 99mTc-SSS lipiodol obtenu avec une PCR et un rendement de marquage élevés (respectivement 92 et 96%). Stable in vitro au moins 24 heures. Ns avons vérifié chez le porc sain, que le 99mTc-SSS lipiodol était stable et qu'il se fixait de façon très sélective au niveau du foie, après injection au niveau de l'artère hépatique. Le 188Re-SSS lipiodol obtenu à basse activité avec une PCR et un rendement élevés (respectivement 94 et 97%). Stable in vitro au moins 48 heures. Ns avons vérifié, après injection au niveau de l'artère hépatique chez le porc sain et le rat porteur d'un CHC, que le 188Re-SSS lipiodol se fixait préférentiellement au niveau du foie et se concentrait dans la tumeur avec un rapport de fixation "tumeur/foie non tumoral" voisin de 4. Nous avons mis en évidence une élimination urinaire et digestive très faible du 188Re-SSS lipiodol à l'inverse de ce qui a été décrit antérieurement avec d'autres marquages du lipiodol à l'iode 131 et au rhénium 188. Ce point témoigne d'une meilleure stabilité in vitro du 188Re-SSS lipiodol. Une étude de survie avec l'utilisation d'un mélange 188Re-SSS lipiodol/131i-lipiodol, de 188Re-SSS lipiodol seul et de 131i-lipiodol seul chez le rat porteur d'un CHC a été réalisée. Avec un recul de 6 mois elle n'a pas permis de mettre en évidence de supériorité du mélange 188Re-SSS lipiodol/131i-lipiodol ni d'efficacité significative du 188Re-SSSlipiodol. Les résultats de cette étude font évoquer une efficacité limitéé du 188Re-SSS lipiodol sur les lésions de relativement petite taille.
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Wiseen, Åberg Erik. "Implementing a PPP-based SSL VPN Client for Clavister Security Gateways." Thesis, Umeå universitet, Institutionen för datavetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-128406.
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In this thesis, we describe how an SSL VPN client utilizing the UNIX program called pppd was developed. pppd enables the creation of point to point links through the Point-To-Protoco l(PPP) which is capable of carrying protocols such as IP, allowing the VPN to connect to the SSL VPN service of Clavisters security gateways. We then perform ananalysis of the degradation of network communication through put caused by this approach. Our findings suggest that the usage of pppd may be the cause of lower than acceptable throughput, making this approach non-viable as the basis for a VPN solution
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Dernaika, Maher. "Molecular Characterization Of Strawberry By Applying Dna Fingerprinting Technique Using Simple Sequence Repeats (ssrs) Markers." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12611258/index.pdf.
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In this study, strawberry fruit was taken as the studied model. An attempt was carried on trying to identify a unique DNA fingerprint in each of the selected different strawberry cultivars of Fragaria x ananassa Duch species available in Turkey. The basis of the study was to examine the fruit characteristics at the molecular level rather than at the morphological level. It is of great importance to differentiate and trace the origin of any variety by examining its DNA by using a very sophisticated molecular technique. In this case, DNA fingerprinting technique depending on the Simple Sequence Repeats (SSRs) markers which are also called Microsatellite markers were used. DNA fingerprinting technique reveals the specific DNA profile which is unique as a fingerprint for a fruit specimen and this DNA profile is the same and constant throughout different parts of the fruit as well as its developmental stages. In this thesis work, nine primers flanking the SSR markers already available in the online databases were designed hoping to detect SSRs that could differentiate among the five selected cultivars of strawberry.
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Masters, Seth Lucian. "The role of the SPRY domain in the SPRY domain containing SOCS box proteins (SSBs) /." Connect to thesis, 2005. http://eprints.unimelb.edu.au/archive/00001571.
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Thesis (Ph.D.)--University of Melbourne, The Walter and Eliza Hall Institute of Medical Research, Division of Cancer and Haematology, Dept. of Medical Biology,Faculty of Medicine,Dentistry and Health Sciences, 2006.<br>Typescript. Includes bibliographical references (leaves 192-210).
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Oliveira, Karine Miranda. "Desenvolvimento de marcadores moleculares EST-SSRs e mapeamento funcional em cana-de-açucar (Saccharum spp.)." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316466.
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Orientadores: Anete Pereira de Souza, Antonio Augusto Franco Garcia<br>Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia<br>Made available in DSpace on 2018-08-08T00:10:19Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006<br>Resumo: A cana-de-açúcar (Saccharum spp.) está entre as espécies de maior importância econômica no mundo, constituindo uma das principais fontes de produção de açúcar e álcool. Apesar do Brasil ocupar posição de destaque, como o maior produtor mundial, os níveis de produtividade são considerados baixos. Os programas de melhoramento para obtenção de novas variedades de cana-de-açúcar, mais produtivas e resistentes a pragas e doenças, podem ser acelerados com o desenvolvimento de marcadores genéticos, PCR específicos, fortemente ligados a genes que controlam as características de interesse. A utilização de marcadores em estudos de mapeamento genético e de QTL¿s (Quantitative Trait Loci) tem proporcionado um importante progresso no conhecimento da estrutura genômica e na genética da cana-de-açúcar. Sabe-se que os ESTs (Expressed Sequence Tags) apresentam grande potencial para serem utilizados com tais finalidades. O projeto de seqüenciamento de ESTs (SUCEST), do programa Genoma da FAPESP, identificou cerca de 43 mil clusters que representam os genes de cana-de-açúcar, potenciais para serem utilizados no desenvolvimento de marcadores genéticos. Neste contexto, o presente trabalho teve como objetivo desenvolver e mapear marcadores EST-SSRs em uma progênie derivada do cruzamento entre duas variedades pré-comerciais de cana-de-açúcar, complementando os programas de mapeamento genético desta população. Uma busca no banco de dados do SUCEST resultou na identificação de marcadores microssatélites ou SSRs (Single sequence repeats) em 2005 clusters. Trezentos e setenta e dois locos EST-SSRs foram desenvolvidos e analisados e, destes, 149 foram selecionados para estudo de mapeamento genético. Um total de 2303 marcadores polimórficos (SSRs, EST-SSRs, RFLPs, EST-RFLPs e AFLPs) foi identificado nos 100 indivíduos da progênie F1, dos quais 1669 (72%) eram marcadores em dose simples (1:1 e 3:1), segregantes na população. As análises de mapeamento foram baseadas na metodologia de identificação de marcadores em dosagem única no genoma, com o auxílio dos programas JoinMap (versão 3.0) e OneMap. Para a formação dos grupos de co-segregação (GCs) utilizou-se LOD 5 e fração de recombinação de 0.35. A função de mapeamento de Kosambi foi adotada para conversão das freqüências de recombinação em distâncias de mapa em centiMorgans (cM). Dos 1669 marcadores segregantes, 664 (40%) foram distribuídos em 192GCs, gerando um mapa com 6261.1 cM de comprimento. Os 192 GCs foram agrupados em 14 prováveis grupos de homologia. Cento e treze dos 149 EST-SSRs avaliados foram mapeados e apresentaram homologia a genes conhecidos de outras espécies. A adição dos marcadores provenientes de seqüências expressas, aumentou a cobertura e densidade do mapa prévio desta população, possibilitando também a construção do primeiro mapa funcional de cana-de-açúcar. Os EST-SSRs desenvolvidos têm potencial
de utilização na detecção de QTL¿s associados a características de importância econômica para a cultura da cana-de-açúcar<br>Abstract: Sugarcane (Saccharum spp.) is one of the most important cash crops, highly contributing towards the production of raw sugar and bioethanol produced worldwide. Even though Brazil is the major producer, sugar yield is considered low. Breeding programs for the attainment of new improved sugarcane varieties, which are more productive and more resistant to plagues and illnesses, could be sped up with the development of genetic markers that are PCR-specific and strongly linked to genes that control the desired agronomic traits. The use of genetic markers in genetic mapping and QTL (Quantitative Trait Loci) studies has allowed important progress in the knowledge of the genomic structure and genetics of sugarcane. It is a known fact that the ESTs (Expressed Sequence Tags) have great potential to be used with such purposes. The Sugarcane Expressed Sequence Tag Project (SUCEST) has identified about 43000 clusters that represent the sugarcane genes with a potential to be used in the development of genetic markers. In this context, the objective of the present work was to develop and map EST-SSR markers in a progeny obtained by the cross between two pre-commercial sugarcane varieties, complementing the genetic mapping programs of this population. A search in the SUCEST database resulted on the identification of the microssatellites or SSR (Single sequence repeats) markers in 2005 clusters. Thus, three hundred and seventy two EST-SSR loci had been developed and analyzed and, out of these, 149 were selected for mapping analyses. A total of 2303 polymorphic markers (SSRs, EST-SSRs, RFLPs, EST-RFLPs and AFLPs) were identified among the 100 F1 individuals, of which 1669 (72.5%) were single dose (SD ¿ segregated 1:1 and 3:1) markers. Map analyses were carried out using JoinMap (version 3.0) and OneMap algorithm, based on a single-dose marker approach. The linkage relationships of simplex markers were determined at a LOD score threshold of 5 and a recombination fraction threshold of 0.35 and map distances were derived from the recombination fraction using the Kosambi function. Out of these 1669 SD markers, 664 (40%) were scattered onto 192 co-segregation groups (CGs) with a total estimated map length of 6261.1 cM. Using both genomic and EST-derived SSR and RFLP, 120 of the 192 CGs were formed into fourteen putative homology groups (HGs). One hundred and thirteen of the 149 EST-SSRs evaluated were mapped and presented homology to previously studied genes of other species. The addition of the EST-derived markers increased the coverage and density of the previous map of this population, which also enabled the construction of the first functional linkage sugarcane map. The EST-SSRs developed have the potential to be used in the detection of QTLs associated to important economic traits for sugarcane culture<br>Doutorado<br>Genetica Vegetal e Melhoramento<br>Doutor em Genetica e Biologia Molecular
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Schuck, Mariane Ruzza. "Caracterização molecular de variedades de videira (VITIS spp.) de Santa Catarina por marcadores microssatélites (SSRs)." Florianópolis, SC, 2007. http://repositorio.ufsc.br/xmlui/handle/123456789/90280.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias. Programa de Pós-Graduação em Recursos Genéticos Vegetais.<br>Made available in DSpace on 2012-10-23T08:02:20Z (GMT). No. of bitstreams: 1
246930.pdf: 1667453 bytes, checksum: 9c6854327742d0448d006ae863e79f08 (MD5)<br>A videira é a frutífera economicamente mais importante no mundo e é cultivada para que seus frutos produzam uvas de mesa, suco, uvas passas e vinhos. A espécie Vitis vinifera L. é cultivada pelo mundo todo e muitas variedades importantes têm sido selecionadas durante os séculos. O inventário das variedades de videira descritas na literatura revela a existência de mais de 14000 variedades. Esta grande diversidade genética foi originada pela antiga prática da propagação vegetativa. A dispersão das variedades de videira ou populações de diferentes origens por meio da migração e do comércio conduziu a um grande número de sinônimos, homônimos e ambigüidades na identificação das variedades. Deste modo, a análise genética molecular, baseada no polimorfismo de DNA detectado em locos marcadores tem sido útil no estudo de diversidade genética das coleções de germoplasma facilitando a classificação correta de amostras, bem como a identificação de sinônimos e homônimos. A coleção de germoplasma de videira do Estado de Santa Catarina mantém plantas de videiras que necessitam ser identificadas e caracterizadas corretamente a fim de evitar duplicatas ou sinonímias. Este trabalho objetivou caracterizar e identificar as variedades de videira, das coleções públicas e privadas de Santa Catarina, por marcadores microssatélites. Foram utilizados cinco painéis de marcadores microssatélites (multiplex-seqüenciador) constituídos por primers marcados com fluorocromos para a genotipagem semi-automática em seqüenciador de DNA de 246 amostras de videira, coletados em 7 regiões do Estado de Santa Catarina. Dez locos marcadores distribuídos no genoma da videira foram genotipados utilizando os painéis multiplex e os dados utilizados para identificar variedades sinônimas, de origem desconhecida e erros de identificação, e criar um banco de dados referencial informatizado das variedades de videira (Vitis spp.) de Santa Catarina. Das 246 amostras genotipadas, 181 foram identificadas com segurança e o restante (n=65) por terem amplificado em menos de 6 locos SSRs, não foram identificadas, pois pouco ou nenhum dado referente ao tamanho dos alelos foi suficiente para identifica-lás com segurança. A análise com microssatélites das 181 amostras identificadas resultou em 68 perfis moleculares únicos (68 variedades diferentes), 10 casos de variedades sinônimas (entre as variedades coletadas em Santa Catarina quando comparadas com aquelas encontradas nos 'database' e literatura internacional), identificação de 10 amostras de origem genética desconhecida, 7 casos de erro de identificação e 7 casos de variabilidade intravarietal. Um grande número de alelos pôde ser detectado, o que comprovou a natureza multialélica deste tipo de marcador e a alta eficiência na caracterização e discriminação do germoplasma de Vitis sp. a nível de variedade, gerando fingerprintings únicos para um grande número de genótipos. A metodologia de genotipagem utilizando painéis de microssatélites marcados com fluorescência e genotipados em seqüenciador automático de DNA apresentada mostrou ser um procedimento eficiente, rápido e simples na detecção de polimorfismo SSRs.
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Orlando, Giulia. "Molecular mechanisms of ARF regulation in response to DNA damage." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:fde8ab19-bc7f-4ad8-8396-6c5f5f385d34.
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DNA is a highly unstable molecule. Endogenous souces of DNA damage, such as reactive oxygen species (ROS), can cause DNA damage and it has been estimated that 20000 lesions occur in a cell per day. BER is the major pathway for the repair of these lesions and therefore maintains genome stability, thus preventing the development of human diseases such as neurodegenerative diseases and cancer. Therefore, if BER cannot accomplish the repair, accumulation of DNA damage occurs, triggering different cellular responses, such as cell cycle delay and senescence. The ARF tumour suppressor protein, the gene of which is frequently mutated in many human cancers, plays an important role in the cellular stress response by orchestrating upregulation of p53 protein. Moreover, ARF expression is upregulated in senescent cells, suggesting that ARF induction might be triggerred in response to persistent DNA damage. Although ARF has been reported to be important in the regulation of proteins involved in the DNA damage response, its role is still controversial. Here, it has been shown that ARF gene transcription is induced by DNA strand breaks (SBs) and that ARF protein accumulates in response to persistent DNA damage generated by disabling BER. These data suggest that PARP1-dependent poly(ADP-ribose) synthesis at the sites of SBs initiates DNA damage signal transduction by reducing the cellular concentration of NAD<sup>+</sup>, thus inhibiting SIRT1 activity and consequently activating E2F1-dependent ARF transcription. These findings suggest a vital role for ARF in DNA damage signalling, and furthermore explain the critical requirement for ARF inactivation in cancer cells, which are frequently deficient in DNA repair and accumulate DNA damage.