Tesi sul tema "AI-2"

Thesis (Ph. D.) -- University of Maryland, College Park, 2004.
Thesis research directed by: Cell Biology & Molecular Genetics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Bachelors
Engineering
Electrical Engineering

Les lipoproteines de haute densite (hdl) participent a l'homeostasie du cholesterol cellulaire en assurant le processus de son transport retour des tissus peripheriques vers le foie ou il peut etre elimine par les voies biliaires. C'est notamment grace a cette fonction d'epuration du cholesterol que l'on attribue aux hdl un role protecteur vis-a-vis des maladies cardiovasculaires. Si l'interaction specifique des hdl avec le tissu hepatique est communement admise, l'identification d'un domaine proteique de liaison au sein des hdl reste sujette a controverse. Nous avons precedemment decrit l'existence de deux familles de sites de liaison, de haute et basse affinite, pour les hdl3 sur une lignee cellulaire d'hepatocarcinome humain (hepg2), et l'implication de l'apolipoproteine ai (apo ai), proteine majoritaire des hdl, dans cette interaction. Afin d'identifier un domaine de liaison, les cellules hepg2 ont ete utilisees comme matrice d'affinite dans des etudes d'association dissociation de fragments trypsiques d'hdl3, permettant ainsi d'isoler et de caracteriser un peptide couvrant la region 62-77 de l'apo ai. Les parametres de liaison du peptide synthetique correspondant traduisent une interaction de haute affinite comparable a celle de l'apo ai libre. Les experiences de competitions croisees entre ce peptide et l'apo ai confirment qu'ils partagent les memes sites de liaison sur les cellules hepg2. Par ailleurs ces sites ne semblent pas impliquer le recepteur sr-bi (scavenger receptor class b type 1) recemment identifie, puisque aucune liaison specifique de ce peptide n'est observee sur des cellules epitheliales surexprimant ce recepteur. Cependant, le maintien apparent d'une liaison aux cellules hepg2 de l'apo ai deletee de la region 62-77 ne permet pas de conclure a l'unicite de ce domaine, et suggere l'existence d'un domaine de liaison redondant au sein de l'apolipoproteine. La presence de sequences consensus au sein de l'apo ai permet d'etayer cette hypothese.

The depletion of non-renewable energy resources, the environmental concern over the burning of fossil fuels, and the recent price rises and instability in the international oil markets have all combined to stimulate interest in the use of fermentation processes for the production of alternative bio-fuels. As a fuel, ethanol is mainly of interest as a petrol additive, or substrate, because ethanol-blended fuel produces a cleaner, more complete combustion that reduces greenhouse gas and toxic emissions. As a consequence of the surge in demand for biofuels, ethanol producing microorganisms, such as the bacterium Zymomonas mobilis, are of considerable interest due to their potential for industrial-scale bioethanol production. Although bioethanol has traditionally been produced in batch fermentation with the yeast Saccharomyces cerevisiae, there are advantages in using Z. mobilis as an alternative for bioethanol production. In comparison to yeast, Z. mobilis grows and ferments rapidly, without the requirement for the controlled supply of oxygen during fermentation, and has a significantly higher ethanol product rate and yield. Most importantly, it has a high tolerance for ethanol. Bacteria communicate with one another using chemical signalling molecules. In general, chemical communication involves producing, releasing, detecting, and responding to small hormone-like molecules termed autoinducers (AI). This process allows bacteria to monitor the environment for other bacteria and to alter behaviour on a population-wide scale in response to changes in the number and/or species present in a community. Currently, there are three well-defined classes of molecules that serve as the paradigms for chemical signaling in bacteria: oligopeptides, AI-1 (AHLs) and AI-2. Oligopeptide signalling is the predominant signal used by Gram-positive bacteria, and AHLs (acyl-homoserine lactones) are for species-specific communication in Gram-negative bacteria. Finally, the LuxS/AI-2 pathway is generally considered as involved in interspecies communication because the luxS gene, which is responsible for AI-2 production, is found in various bacteria. Many physiological functions in bacteria such as toxin, virulence factor and bacteriocin production, biofilm formation, bioluminescence, type III secretion, have been shown to be under the control of AI-2 quorum sensing. In Z. mobilis, in vitro synthesized and in vivo produced AI-2 treatment enhanced ethanol production by this bacterium up to a maximum of 50% in comparison with untreated control cells. This appears attributable to the overproduction of the glycolytic enzymes, enolase and pyruvate carboxylase, which are only rarely found in bacteria and the key enzymes for ethanol production. From the perspective of interspecies communication, enhanced ethanol production in Z. mobilis, under the control of the AI-2 signalling molecules, could represent a good example of a bacterium that does not produce AI-2, but responds to it. Another interesting finding is that two extracellular proteins from Z. mobilis, ZMO0994 and ZMO0134 which were originally induced by AI-2, were secreted when they were cloned, transformed and expressed in E. coli strain BL21 DE3; since it is generally accepted that nonpathogenic strains of E. coli, particularly derivatives of K12, do not secrete proteins under routine growth conditions. Presumably, these proteins possess signal sequences for secretion that could be used to provide a strategy for their use as carriers of recombinant proteins produced in E. coli K12. The merit of this system is that there would be few contaminant cytoplasmic proteins, and could possibly solve problems in protein purification, such as protease activity, protein misfolding and inclusion body formation. Finally, the discovery that the metabolic pathway leading to ethanol production is regulated by AI-2 is of considerable biotechnological importance because it will provide a basis for further engineering of strains for more efficient ethanol production. Indeed, engineering Z. mobilis by introducing the genes that encode Pfs and LuxS to produce AI-2, would be a means to stimulate increased ethanol production.

This thesis may be interesting for developers within video game industry, people who design the behaviour of agent systems, or those interested in complex robotic control systems. What potential fields give to the world of AI is a new way to implement the behaviour of the agents, giving weights to all the elements in the world, so the agent can decide if making some action deserves the cost, the combination of several potential fields is what makes this technique so efficient. An agent was created applying this technique. Implemented as a client application, the agent used the Quake protocol to connect and communicate with the server. Some tests were run on the model concerning the different functionalities a gamer agent should implement. The model turned out to be a success in a virtual environment like quake 2. Taking care of all the entities in the map and environmental factors, the agent is able to keep his state in balance, move to the most interesting positions and be able to face combat situations. The implementation is clean and mathematical oriented. Using algorithms as the heart of the model, we make the code lightweight in comparison with old bot models.
The purpose of this thesis was to test an artificial intelligence technique called "Multiple Potential Fields" in the programming of an agent playing in a multiplayer game as Quake 2. The results stated that the technique is really interesting to apply in an virtual real-time environment, having some clear advantages compared to other techniques.
hectorvcaz@hotmail.com

Multiplayer online battle arena (MOBA) games and games in general offer developers opportunities to design and test AI to further push research within the area. MOBA is a genre that has seen an increase in popularity during recent years alongside a rapidly growing esports scene.  The game's main purpose is ultimately to be enjoyed and played by human players, who often come up with and are encouraged to create their own strategies in order to beat the game or win out over their opponents.  This thesis will explore how mimicking human behavior in AI and using statistics from human players can be beneficial to AI design. The AI will be developed in a framework similar to that used by the Conference of Games for their Dota 2 5v5 AI competition. Three different strategies will be created, each of which will mimic some aspect of human behaviour, and then tested against the built-in AI in Dota 2. All the developed AI’s managed to win with varying results. The results showed some support for the notion that human gameplay and statistics can be beneficial to AI design. There are, however, difficulties with the complexity of the game that is Dota 2.

Cell-to-cell communication, termed quorum sensing, mediated by AI-2 like activity, has been reported to regulate the expression of a variety of genes in E. coli O157:H7. A previous study in our laboratory has shown that foods can contain compounds that can interfere with AI-2 signaling. The underlying hypothesis of our studies is that the autoinducer molecules such as AI-2 are involved in the virulence and survival of enteric bacterial pathogens on food and food ingredients. The influence of AI-2 like activity on the survival and expression of virulence genes (hha and yadK) in E.coli O157:H7 was studied when the organism was stored in different types of ground beef extracts such as: cooked, uncooked, and autoclaved. The survival was observed at refrigeration temperature, while change in gene expression was studied using real-time PCR. Higher survival was observed in the cell exposed to cell free supernatant (CFS) containing AI-2 like molecules, compared to the one which was exposed to heat degraded AI-2 like molecules. The survival of cells was higher when exposed to cooked ground beef extracts compared to uncooked and autoclaved ground beef extracts. Similarly, higher gene expressions of both hha and yadK genes were observed in cells that were exposed to cooked beef extract samples as compared to samples that wereuncooked or autoclaved. About a 2 fold higher gene expression for both hha and yadK gene was observed when cells were subjected to cooked ground beef extracts in the presence of AI-2 like molecules compared to the ones exposed to uncooked ground beef extracts in the presence of AI-2 like molecules. Likewise, 3-fold higher gene expression was observed for cells exposed to cooked ground beef extracts compare to autoclaved ground beef extracts in the presence of AI-2 like molecules. The results suggest that the survival and virulence of enteric bacterial pathogens such as E.coli O157:H7 can be influenced by the interaction of food components and autoinducers such as AI-2, that are involved in bacterial cell communications.

Orientadores: Arnaldo Yoshiteru Kuaye, Dirce Yorika Kabuki
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Enterococcus faecium e Enterococcus faecalis são espécies de patógenos oportunistas que infectam principalmente imunocomprometidos. Estas espécies são encontradas em produtos lácteos e possuem capacidade de formar biofilme em superfícies que contatam com os alimentos. A sua remoção é muito dependente dos procedimentos de higienização. Os Enterococcus spp. utilizam o sistema de comunicação célula-célula (quorum sensing) para a formação de biofilmes. A formação de biofilme mono e multiespécie, a eficácia dos procedimentos de higienização no controle destes biofilmes e a produção de moléculas sinalizadoras de quorum sensing por cepas de E. faecalis, E. faecium, Bacillus cereus e Listeria monocytogenes foram avaliadas. Os ensaios foram realizados com cupons de aço inoxidável e variando-se a temperatura (7, 25 e 39 °C) e o tempo (0, 1, 2, 4, 6 e 8 dias). Após 1 e 8 dias de contato nas temperaturas de 25 e 39 °C, os cupons foram submetidos a diferentes processos de higienização. Os sanitizantes testados foram: hipoclorito de sódio (0,2%), ácido peracético (0,2%), quaternário de amônio (3,0%) e biguanida (1,0%). A detecção das moléculas sinalizadoras de quorum sensing AI-2 foi realizada através da avaliação do gene luxS e de ensaio biológico de bioluminescência. Nenhum dos micro-organismos avaliados foi capaz de formar biofilmes a 7 ?C. Enterococcus sp. foram capazes de formar biofilmes, com contagens acima de 8 log ufc/cm2 para as temperaturas de 25 e 39 °C após 8 dias de contato. Em cultivo multiespécie, a temperatura 25 °C favoreceu o desenvolvimento do biofilme de L. monocytogenes (contagens acima de 6 log ufc/cm2). Por sua vez, a 39 °C observou-se o efeito negativo no desenvolvimento do biofilme de L. monocytogenes em cultivo misto, com redução significativa nas contagens ao longo do tempo (valores abaixo de 0,4 log ufc/cm2). As contagens de B. cereus, para ambas as temperaturas em diferentes tempos de exposição situaram-se abaixo de 4,1 log ufc/cm2. Em contrapartida, a contagem de esporos de B. cereus evoluiu ao longo do tempo, atingindo contagens em torno de 4,6 log ufc/cm2. A limpeza com tensoativo aniônico complementada por outra etapa (limpeza ácida, limpeza ácida + sanitização ou sanitização) foi capaz de remover os biofilmes mono e multiespécie em todas as condições testadas. O ácido peracético foi o sanitizante mais eficiente e a biguanida o menos eficiente. Todas as cepas de Enterococcus spp. e B. cereus apresentaram o gene luxS e induziram o fenômeno de bioluminescência em Vibrio harveyi BB170, indicando a presença de autoindutores AI-2
Abstract: Enterococcus faecium and Enteroccus faecalis are opportunistic pathogens species that infect mainly immunocompromised individuals. These species are found in dairy products and are capable of forming biofilms on surfaces that contact with food. Their removal is highly dependent on the cleaning procedures. It is known that enterococci use the cell-cell communication (quorum sensing) to biofilm formation. The formation of mono- and multi-species biofilm, the effectiveness of sanitization procedures to control these biofilms and the production of signaling molecules of quorum sensing (AI-2) by strains of E. faecalis, E. faecium, Bacillus cereus and Listeria monocytogenes were evaluated in this work. The biofilms were grown on stainless steel coupons at various incubation temperatures (7, 25 and 39 °C) and times (0, 1, 2, 4, 6 and 8 days). After 1 and 8 days of contact at 25 and 39 °C, the coupons were subjected to different sanitation procedures: anionic tensioactive cleaning, acid-anionic tensioactive cleaning, sanitization, anionic tensioactive cleaning + sanitization, acidic- anionic tensioactive cleaning + sanitization and chlorinated alkaline cleaning. The sanitizers tested were: sodium hypochlorite (0.2%), peracetic acid (0.2%), quaternary ammonium (3%), and biguanide (1%). The detection of AI-2 molecules was performed by evaluating the luxS gene and biological bioluminescence assay. None of the microorganisms evaluated was able to form biofilms at 7 °C. Enterococcus sp. were able to form biofilms, with counts above 8 log CFU/cm2 for the temperatures of 25 and 39 °C after 8 days of contact. In multi-species culture, the temperature of 25 °C favored the development of L. monocytogenes biofilms (counts above 6 log CFU/cm2). On the other hand, at 39 °C it was observed a negative effect in the development of L. monocytogenes biofilms in mixed culture, with a significant reduction in counts over time (values below 0.4 log CFU/cm2). The counts of B. cereus, for both temperatures at different exposure times were below 4.1 log CFU/cm2. In contrast, the spore counts of B. cereus evolved over time, reaching scores of around 4.6 log CFU/cm2. The anionic tensioactive cleaning complemented by an aditional step (acid cleaning, acid cleaning + sanitization or sanitization) was able to remove mono- and multi-species biofilms in all tested conditions. The peracetic acid was the most effective sanitizer and the less efficient was biguanide. All strains of Enterococcus spp. and B. cereus showed the luxS gene and induced the phenomenon of bioluminescence in Vibrio harveyi BB170, indicating the presence of AI-2 autoinducers
Doutorado
Tecnologia de Alimentos
Doutora em Tecnologia de Alimentos

In nature, bacteria can exist as a multi species consortium of cells adherent to a surface and able to co-ordinate cellular metabolism via quorum sensing molecules. The effect of biofilm formation can have both positive as well as negative impacts on human society. In order to engineer systems where the positive impacts of biofilms are enhanced and the negative impacts are curbed, a detailed understanding of the environmental signals and molecular mechanisms that trigger the formation and maintenance of biofilms is necessary. As a first step in this direction, the molecular mechanisms underlying the formation of biofilms arc investigated in Bacillus cereus; biofi Im formation in which has positive impacts on society such as. aiding waste water treatment and bioremediation as well as negative impacts such as biofouling of implants and causation of disease. This investigation of cell surface characteristics and production of extracellular polymeric substances via Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, zetapotcntial analysis and various techniques in proteomics suggest that during biofilm formation, the surface chemistry of the cells and the composition of the EPS changes, most likely by glyeosylation of surface and secreted polymers, in order to aid biofilm formation and that biofilms arc predominantly stabilized by electrostatic interactions between the cell surface and EPS polymers. This work also establishes that the presence of other microorganisms in the culture environment, mimicked by the addition of quorum sensing signal, Al-2 affects the surface chemistry, motility, cellular metabolism and EPS production in Bacillus cereus and improves biofilm formation in Bacillus cereus. The use of quorum sensing signals could therefore be a possible mechanism for biofilm control. However, additional investigations into the glycobiome of Bacillus cereus and the regulation of post translation control need to be carried out before quorum sensing signals can be employed to reliably control biofilm formation in Bacillus cereus.

O presente trabalho trata do estudo da oligomerização de eteno catalisada pelo complexo Ni[MeCN]6[BF4]2 imobilizado por adsorção seletiva nos suportes inorgânicos [Al]-MCM41 e SiO2 associado ao agente alquilante AlEt3. O sistema suportado foi avaliado em suspensão empregando diclorometano como solvente, em um reator semicontínuo com alimentação a pressão constante de eteno. A caracterização por DRIFT e XPS do sistema suportado em [Al]-MCM-41 mostrou que a esfera de coordenação do níquel foi modificada. As análises de TEM e XRD demonstraram que a organização dos poros da [Al]-MCM-41foi mantida após a etapa de imobilização do complexo. A análise de TEM demonstrou ainda que o diâmetro dos poros é de 3 nm. A análise de adsorção de N2 demonstrou que a imobilização do complexo de níquel ocorreu dentro dos poros dos suportes [Al]-MCM-41 e SiO2.pois as áreas superficiais tiveram uma diminuição média de 25% após o processo de imobilização. Os resultados referentes aos testes catalíticos mostraram que esses novos sistemas são ativos na dimerização e trimerização de eteno, A concentração do agente alquilante (AlEt3) mostrou-se um parâmetro muito sensível em relação a produção seletiva de buteno-1, pois a medida que era aumentada essa proporção os sistemas que apresentavam o suporte [Al]-MCM-41, aumentavam sua seletividade mas diminuíam sua freqüência de rotação. Foram relatados para comparação, resultados de experiências realizadas com o mesmo complexo e o mesmo agente alquilante, mas em fase homogênea. Diferenças significativas foram observadas em termo de atividade catalítica, seletividade e sensibilidade em relação à proporção relativa de AlEt3 com o complexo de níquel. A reação conduzida com o complexo imobilizado, nas nossas condições reacionais, leva à produção em buteno-1 com uma seletividade 84% para o sistema Ni–[Al]-MCM-41 e de 75% para o sistemas Ni-SiO2 enquanto em condições similares, em meio homogêneo, a seletividade em buteno-1 é de 67%.
The present work deals with the study of the oligomerization of ethene catalyzed by the immobilized Ni[MeCN]6[BF4]2 complex for selective adsorption in the inorganic supports [ Al]-MCM41 and SiO2, associated with alkylation agent AlEt3. The supported system was evaluated in diclorometane suspension using as solvent, in a semicontinuous reactor with feeding at constant pressure of ethene. The characterization for DRIFT and XPS of the system supported in [Al]-MCM-41 showed that the sphere of coordination of nickel was modified. The analyses of tem and XRD had demonstrated that to the organization of the pores of [Al]-MCM-41was kept after the stage of immobilization of the complex. The analysis of TEM still demonstrated that the diameter of the pores is 3 nm. The analysis of adsorption of N2 demonstrated that the immobilization of the nickel complex occurred inside of the pores of the supports [Al]-MCM-41 and SiO2.because the superficial areas had an medium reduction of 25% after the immobilization process. The results referring to the catalytic tests had shown that these new systems are active in the dimerization and trimerization of ethene, The concentration of the alkylation agent (AlEt3) revealed to be a very sensible parameter in relation to the selective production of butene-1, Therefore ,as was increased this ratio the systems that presented the support [Al]-MCM-41, as increased its selectivity but they decreased its turnover frequency. They had been told for comparison, resulted of experiences carried through with the same complex and the same alkylation agent, but in homogeneous phase. Significant differences had been observed in term of catalytic activity, selectivity and sensitivity in relation to the relative ratio of AlEt3 with the nickel complex. The reaction lead with the immobilized complex, in our reactional conditions, leads to the production in butene-1 with selectivity 84% for the Ni-[Al]-MCM-41 system and of 75% for the Ni-SiO2 systemswhile in similar conditions, homogeneous way, the selectivity in buteno-1 is of 67%.

In most games today the movements of computer players is controlled by a web of waypoints that have been predefined by the creators of the map, or automatically generated by an application on beforehand. This data is precompiled to save precious CPU cycles for the player of the game, but what if we want these computer players to be able to explore how to get around the map by themselves? How could this be done and how would the result change if we had several of these players cooperating to explore the map? We explore some of the possibilities for exploration and discovery of maps using approaches that is often found in robotics. We also look at what happens when there is a penalty for communicating between these computer players, and what effect different amounts of map coverage will have on the performance of them. By setting up a test environment inside an existing commercial computer game we developed a client side bot system that made it possible for us to test different parameters and settings. Based on the analysis of the test results we propose ways to describe and predict the effects of the number of bots and the communication rate, and we describe several ways of how to further advance on these ideas and experiments.

When a company includes a new technology or innovation into their value proposition, customers may perceive it as an enhancement or deterioration. This phenomenon was explored in this study with a case study of a present case in the esports industry. Research have shown that AI (Artificial Intelligence) technology can be used to predict which team is going to win in a match in the esports game DotA 2. A prototype AI called Znipe Sense was developed and analyzed during this study to answer the question: How can a predictive AI affect the value proposition of live esports consumption? Znipe Sense was included into Znipe Esports’ value proposition during a tournament in February 2018. It was observed that Znipe Sense could predict outcomes of professional matches with a higher accuracy than human experts. The observations of Znipe Sense, an interview with experienced players, interviews with business professionals and internal company documents were used as empirical material for the analysis. How Znipe Sense affected the value proposition was analyzed through the factors: Performance, Ease-of-use, Reliability, Flexibility and Affectivity, also known as the PERFA framework. It was concluded that a predictive AI can enhance the value proposition of live esports consumption through the Performance and Ease-of-use factors, and it would not affect the value proposition through Reliability or Flexibility. However, in the analysis of the Affectivity factor it was identified that there is a risk related to negative effects of gambling addiction that could deteriorate the value proposition.
När ett företag inkluderar en ny teknik eller innovation i sitt värdeerbjudande kan kunderna uppleva det som en förbättring eller försämring. Detta fenomen undersöktes i denna studie med en fallstudie av ett aktuellt fall i esportsindustrin. Forskning har visat att AI (Artificiell Intelligens) teknik kan användas för att förutsäga vilket lag som kommer att vinna i en match i esports spelet DotA 2. En AI prototyp, Znipe Sense, utvecklades och analyserades under denna studie för att svara på frågan: Hur kan ett prediktivt AI påverka värdeerbjudandet av live esports konsumtion? Znipe Sense inkluderades i Znipe Esports värdeerbjudande under en turnering i februari 2018. Det observerades att Znipe Sense var bättre än mänskliga experter på att förutse det vinnande laget i professionella matcher. Observationerna av Znipe Sense, en intervju med erfarna spelare, intervjuer med affärsfolk och interna företagsdokument användes som empiriskt material. Hur Znipe Sense påverkade värdeerbjudandet analyserades genom faktorerna: ”Performance”, ”Ease-of-use”, ”Reliability”, ”Flexibility” och ”Affectivity”, även känt som PERFA-ramverket. Slutsatsen visar på att ett prediktivt AI kan öka värdeerbjudandet av live esports konsumtion genom Performance och Ease- of-use faktorerna, och att värdeerbjudandet inte skulle påverkas genom Reliability och Flexibility. I analysen av Affectivity-faktorn identifierades emellertid att det finns en risk i relaterat till negativa effekter av spelberoende som kan försämra värdeerbjudandet.

Bacterial quorum sensing is regarded as a novel target for the design of antimicrobials. Based on lead structures identified from HTS, 39 analogues have been synthesized and evaluated in Vibrio haveyi. Potent inhibitors with IC50 values at single-digit micromolar concentrations for AI-2 mediated quorum sensing have been identified. On the second project, post-synthesis modifications of DNA provide easy functionalizations for expanded applications such as aptamer selection. A CBT-modified thymidine analogue (CBT-TTP) has been synthesized and used for enzymatic incorporation into DNA. Post-synthesis modifications through condensation with 1,2-aminothiol for installation of a boronic acid moiety or a fluorophore have been achieved. On the third project, H2S has been recognized as an important gasotransmitter and its concentration is relevant to a variety of diseases. A novel fluorescent probe (DNS-Az) has been developed for quantitation of H2S in aqueous solutions. This probe has been used to measure H2S concentrations in the blood.

Vibrio vulnificus is a model environmental organism exhibiting a classical starvation response during nutrient limitation as well as a non-culturable state when exposed to low temperatures. In addition to these classic global responses, this organism is an opportunistic pathogen that exhibits numerous virulence factors. This organism was chosen as the model organism for the identification of regulators of the viable but nonculturable response (VBNC) and the starvation-induced maintenance of culturability (SIMC) that occurs when cells are starved prior to low temperature incubation. In order to accomplish this, three indirect approaches were used; proteomics, investigation of intercellular signalling pathways and genetic analysis of regulators involved in these responses. Two-dimensional gel electrophoresis was used to identify proteins expressed under conditions that induced SIMC. It was determined that carbon and long-term phosphorus starvation were important in the SIMC response. V. vulnificus was shown to possess genes, luxS and smcR, that are homologues of genes involved in signalling system system 2 in Vibrio harveyi. Signal molecules were produced upon starvation and the entry to stationary phase in V. vulnificus. Furthermore, a null mutation in smcR, a transcriptional regulator was shown to have pleiotropic effects in V. vulnificus, including up-regulation of numerous virulence factors and a defect in starvation survival and development of the SIMC response. We propose that V. vulnificus possesses a signalling system analogous to that of system 2 in V. harveyi, and that this system is involved in the regulation of stationary phase and starvation adaptation in this organism.

Carbohydrates are known to play important roles in a large number of physiological and pathological processes. Conceivably, “binders” of carbohydrates of biological importance could be used as diagnostic and therapeutic agents. Currently, lectins are the major available tools in research for carbohydrate recognition. However, the available lectins often have cross-reactivity issues, along with the high costs and stability issues. Therefore, there is a critical need to develop alternatives (lectin mimics). In this regard, there have been very active efforts in developing different “binders”, such as small molecule lectinmimics and aptamers. Among all the small molecule lectinbmimics developments, boronic acid stands out as the most important building blocks of the sensors design for carbohydrates biomarkers due to its intrinsic binding affinities with diols. To address a fundamental question that whether boronic acid also binds to six-membered ring sugars, with very limited precedents, we provided a concrete experimental evidence of the binding. Specifically, a series of isoquinolinylboronic acids were found to have remarkably high binding affinities with fluorescence change upon binding to representative sugars. Most importantly, these isoquinolinylboronic aicds showed weak but very encouraging bindings with six-membered sugar model. All these promising results paves the way of using boronic acids, especially isoquinolinylboronic acid as building blocks for chemosensors design for biological carbohydrates biomarkers, which universally contain six-membered ring and liner diols. Aptamer provides another alternative way for sensors development for carbohydrates biomarkers as lectin mimics. Compared to lectins, they are normally cheaper and more stable. However, there is much less options. Another challenging area for aptamer-based lectin mimics development is the difficulty to differentiate changes in glycosylation patterns of a glycoprotein, which affect the function of a glycoprotein and thus recognized as biomarkers. To address this major challenge, our group first demonstrated that the incorporation of a boronic acid into DNA would allow for the aptamer selection process to gravitate towards the glycosylation site. To examine the generality of boronic acid incorporation, increase the structural diversity, and broaden the application of boronic acid-modified DNA, a series of B-TTP analogues with simplified structures were designed, synthesized, and successfully incorporated into DNA. A simple route was also developed using 1,7-octadiyne as a linker for both Sonogashira coupling with thymidine and CuAAC tethering of a boronic acid moiety. This paves the way for the preparation of a large number of B-TTPs with different structural features for aptamer selection or array analysis. Finally, bacterial quorum sensing has received much attention in recent years because of its relevance to pathological events such as biofilm formation. As one of the very first groups that developed a series of antagonists for AI-2 mediated quorum sensing, we herein designed and synthesized a series of analogues based on the structures of two lead inhibitors identified through virtual screening. Besides, we also examined their inhibitory activities, twelve of which showed equal or better inhibitory activities compared with the lead inhibitors. The best compound showed an IC50 of about 6 mM in a whole cell assay using Vibrio harveyi as the model organism. This encouraging results and SAR discuss also paves the way for the finding of more potent compound through further structure optimization.

Idades de soterramento de grãos de quartzo pelos isótopos cosmogênicos \'ANTPOT.26 Al\' e \'ANTPOT.10 Be\' foram obtidas em depósitos sedimentares que assorearam os sistemas de cavernas associados aos vales cegos dos riachos das Almas e Água de Rega, região de Iraquara (BA). Os resultados também incluem a caracterização faciológica e uma abordagem preliminar sobre a arquitetura dos depósitos, além do mapeamento em campo do contexto geomórfico dos sistemas de condutos e seu preenchimento sedimentar. Coberturas terciárias assentadas sobre todas as unidades pré-cambrianas testemunham que a superfície cárstica e os sistemas de condutosfazem parte de uma longa história de evolução, envolvendo episódios de exposição, soterramento e exumação. Durante os dois últimos milhões de anos, a drenagem superficial e os sistemas de cavernas estavam plenamente articulados na condução de água e sedimentos, com rotas de fluxo subterrâneas que incluíam ainda trechos labirínticos pré-existentes, que serviam de repositório de sedimentos durante os eventos de inundação, proporcionando também, rotas alternativas ao canal,na medida em que o sistema agradava. A sucessiva migração do canal por estas redes labirínticas originou o padrão distributário observado na Lapa Doce e na Gruta da Torrinha. Os depósitos sedimentares estudados nas cavernas dividem-se em dois grupos: fluviais e de água estagnada. Osdepósitos fluviais ocorrem na base e são constituídos por fácies de canal e fácies de inundação. As idades de soterramento de grãos de quartzo destes sedimentos apontam para um período de assoreamento fluvial compreendido entre 1,91±0,12 e 0,36±0,08 milhões de anos para o sistema Lapa Doce-Torrinha (riacho Água de Rega) e 1,37±0,15 e 0,87±0,17 milhões de anos para o sistema Cão-Talhão (riacho das Almas). No sistema Lapa Doce-Torrinha as idades de soterramento concentram-se no intervalo compreendido por dois períodos úmidos (350-450 Ka e 900-1000 Ka), registrados em estudos anteriores através do crescimento de tufas calcárias no semiárido baiano.Tal fato sugere que a agradação fluvial verificada, tanto nos rios quanto nas cavernas, esteja associada a fatores climáticos, particularmente o aumento da carga dos rios derivado da diminuição na estabilidade dos grãos nas vertentes exercida por uma vegetação arbustiva esparsa ou ausente. No topo, os depósitos de água estagnada, preferencialmente compostos por lamas, não possuem estruturas trativas ou de corrente e são associados a uma sedimentação em ambiente freático,para o qual é necessário considerar a subida do nível de base. Gretas de contração, além de relações estratigráficas e erosivas destes depósitos com crostas calcíticas evidenciam que eles não foram depositados em um evento único. Idades U/Th obtidas nas crostas calcíticas apontam para uma deposição durante o Pleistoceno Tardio. Interpreta-se que as lamas foram depositadas durante períodos de elevação do nível de base devido aos eventos úmidos abruptos de escala milenar que ocorreram no nordeste brasileiro ao longo dos últimos 210 ka.
\'ANTPOT.26 Al\' and \'ANTPOT.10 Be\' burial ages have been obtained from quartz grains sampled in extensive sedimentary deposits that fill cave systems associated with Das Almas and Agua de Rega creeks blind valleys, Iraquara region, Bahia (Brazil). The geomorphic context of the caves and their sedimentary record is presented, as well a facies analyses and a preliminary architecture approach for subterranean deposits. Tertiary covers deposited over all Precambrian geological units give evidence that karstic surface and conduit systems are features of a long term evolving landscape, sculpted during episodes of exposure, burial and exhumation. In the last two million years, surface drainage and cave systems were full connected in terms of water and sediment transport.Conduit systems still connected with preexisting passage networks, working as sediment repositories during floods and offering alternative routes to the channels as the systems aggraded. Sucessive channel migration led to the distributary pattern observed in the caves Lapa Doce and Gruta da Torrinha. The cave sedimentary record can be divided into two major categories: alluvial and slackwater deposits. At the bottom of the sediments, channel and flood facies were recognized in alluvial deposits. Quartz simple burial ages point to fluvial aggradation between 1,91±0,12 and 0,36±0,08 My in Lapa Doce-Torrinha cave system (Água de Rega creek) and between 1,37±0,15 and 0,87±0,17 million years in Cão-Talhão cave system (Das Almas creek). Burial ages from Lapa Doce-Torrinha samples group in between two past humid periods (350-450 Ky and 900-1000 Ky) recorded in previous studies from travertines growth in arid regions of Bahia State. This fact suggests that valley and cave aggradation is associated with climate factors, particularly an increase in river load derived from decreased stabilization of hillslopes due to a sparse or absent forest vegetation. At the top of sedimentary pile slackwater deposits are ordinarily muddy without tractive or current sedimentary structures. They are assigned to be deposited in a phreatic environment which, in turn, necessarily requires the base level to rise longer than seasonal floods. Mud cracks, erosive surfaces and stratigraphic relations to calcite crusts and flowstones prove that they were not deposited in a single event. U/Th ages from interstratal calcite crusts point to mud deposition during the Late Pleistocene. Slackwater deposits are interpreted to be a result of sedimentation during successive abrupt wet events defined on millennial time scale for the Brazilian northeast during the last 210ky.

La première partie de ce manuscrit est consacrée à l'inhibition des glycosidases. Ces enzymes sont impliquées dans de très nombreux processus biologiques et, par voie de conséquence, dans de nombreuses maladies (diabète, cancer, maldadies lysosomales etc...). Outre l'intérêt de développer de nouveaux médicaments, les glycosides hydrolases font aussi figure de cibles de choix pour étudier les itinéraires conformationnels au cours de l'hydrolyse de la liaison glycosidique et en particulier au niveau de l'état de transition. La mise en parallèle de l'importance de l'orientation des liaisons C2-O2 et C3-O3 dans la stéréosélectivité des réactions de b-mannopyranosylation dirigées par les groupements 4,6-O-benzylidène, avec le rôle des interactions avec la liaison C3-O3 dans la catalyse enzymatique pour les b-mannosidases, nous a conduits à nous intéresser au développement de nouveaux glycoimidazoles, potentiellement inhibiteurs de ces enzymes. Nous nous sommes attachés à développer ce type de molécules car ils sont considérés, à l'heure actuelle, comme les meilleurs mimes de l'état de transition. La catalyse par les b-mannosidases passerait par un état de transition de type B2,5. Ce chemin conformationnel semble inhabituel mais serait le plus approprié au développement du caractère de double liaison entre le carbone anomérique et l'oxygène endocyclique ainsi qu'à la charge positive lorsque le système est proche de l'état de transition. De plus, il semblerait que la conformation B2,5 soit aussi privilégiée pour les a-mannosidases, ce qui renforce l'intérêt thérapeutique de synthétiser de nouveaux inhibiteurs de glycosidases. La stratégie de synthèse s'appuie sur des travaux de Vasella. Elle repose sur la construction du squelette bicyclique des tétrahydroimidazopyridines, via une réaction de cyclisation intramoléculaire d'oxoéthylamidines intermédiaires, qui permet d'obtenir de nouveaux glycoimidazoles en une quinzaine d'étapes. Dans la seconde partie, sont exposés les travaux concernant la préparation et l'utilisation en synthèse de glutaconaldéhydes oxydés en position 2 et de N-acylaminopentadiènals. Après avoir rappelé l'importance des glutaconaldéhydes et des aminopentadiènals dans les hypothèses de biogenèse des alcaloïdes marins de la famille des manzamines, nous avons vu que ces espèces pouvaient être considérés comme des intermédiaires possibles pour la synthèse d'alcaloïdes marins de la famille des pyrrole-2-aminoimidazoles (P-2-AI). La nouvelle méthode de préparation des sels de glutaconaldéhydes nous a permis de synthétiser un glutaconaldéhyde oxydé en position 2 et de commencer à étudier la réactivité des 2-alkoxy-N-acylaminopentadiènals. Le dernier chapitre de cette partie traite d'une méthode de préparation de N-acyl-5-aminopenta-2,4-diènals via l'ouverture de furfurylamines N-acylées développée en parallèle avec les travaux précédemment cités.

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The present study contemplates in a scient ific way the act ion of air ent raining agents in mortars produced in laboratory and the ef fects on the coat ings appl ied on porous subst rates (ceramic blocks, concrete blocks) . This is an experimental work, aiming to test the effect of the air entraining agents in fresh mortars, hardened state and the remaining ai r in coat ing appl ied. The variables were: ai r content , type of subst rate and sur face finishing. Adopt ing a methodology for varying levels of ent raining ai r, keeping fixed the subst rate, the form of appl icat ion and the type of sur face finishing, evaluat ing the propert ies of mortars in order to obtain the ideal air content of dosage. Other studies were done after evaluat ion of opt imal ai r content , keeping i t as a fixed condi t ion and varying the type of subst rate, appl icat ion type and the type of sur face finishing, in order to analyze thei r inter f erence in the amount of remaining ai r, as wel l as such inter ference coat ing appl ied.
O presente t rabalho aborda a ação da incorporação de ar em argamassas de revest imentos, produzidas em laboratór io, e seus efei tos em revest imentos apl icados sobre substratos porosos (bloco cerâmico, bloco de concreto, super fície de concreto). Trata -se de um estudo experimental , onde se aval ia os efei tos dos adi t ivos incorporadores de ar em argamassas nos estados f resco, no estado endurecido e como revest imento apl icado sendo que as principais variáveis estudadas foram: t ipo de adi t ivo, teor de ar, t ipo de sub st rato, t ipo de cimento e o t ipo de acabamento super ficial . Aval iou-se a inf luência da variação do teor de ar nas propriedades mecânicas das argamassas e revest imentos e ver ificou-se a variação do t ipo de acabamento super ficial influencia na resistência de aderência à tração e no desgaste do corte . Na aval iação das caracter íst icas físicas e das propriedades mecânicas dessas argamassas obteve-se um valor para o teor ót imo de ar incorporado. O estudo que teve como condições fixas o t ipo de subst rato padrão e a forma de apl icação, variando o teor de ar incorporado. Como resul tado constatou -se que há um teor ót imo para incorporação de ar , acima do qual as propriedades no estado f resco e endurecido começam a ser prejudicadas, devendo -se evi tar tais teores. Foi possível ainda veri f icar um melhor desempenho das argamassas com ar incorporado com relação à permeabi l idade à água quando comparadas com as argamassas sem adi t ivo incorporador de ar .

La presente ricerca intende affrontare due questioni tra loro interconnesse. La prima potrebbe definirsi, ormai, un esercizio ineludibile per tutti coloro che intendono confrontarsi con le categorie fondamentali del diritto del lavoro: alludiamo, quindi, alla nota questione della collocazione sistematica e, prima ancora, del modo d’essere delle collaborazioni organizzate dal committente. Si tratta, infatti, di un tema che ha visto cimentarsi l’intera “accademia” del diritto del lavoro e, tuttavia, sembra adesso possibile svolgere una sintesi ragionata sulle opinioni presentate dalla dottrina, grazie alla visuale privilegiata di chi si approccia a tale esercizio “a valle” dell’intervento di interpretazione “autentica” dell’art. 15 del d.lgs. 81 del 2017 nonché dei primi pronunciamenti giurisprudenziali. Il secondo quesito che si intende affrontare è ben espresso dall’ultimo spunto ricostruttivo offerto in merito alla vicenda delle collaborazioni etero organizzate, e cioè se la nuova disciplina offra «maggiore tutele alle nuove fattispecie di lavoro che, a seguito della evoluzione e della relativa introduzione sempre più accelerata delle recenti tecnologie, si stanno sviluppando». L’art. 2 del d.lgs. 81/2015, disponendo che “si applica” la disciplina del rapporto di lavoro subordinato “anche” ai rapporti di collaborazione che si concretano in prestazioni di lavoro esclusivamente personali e continuative, a condizione che le modalità di esecuzione siano organizzate dal committente anche in relazione ai tempi ed al luogo di lavoro, è destinato ad operare nell’area assai controversa del lavoro personale continuativo prestato nell’altrui interesse. E ciò, allo scopo di mettere ordine al noto problema delle prestazioni di lavoro sulla frontiera tra subordinazione e autonomia, al quale il lavoro a progetto non aveva saputo dare una risposta adeguata. Nel presente elaborato, si procederà, anzitutto, alla ricostruzione dello summa divisio che caratterizza la nostra materia e con la quale devono, sempre, confrontarsi tutte le “nozioni” che intercettano e descrivono un modo d’essere di una prestazione di lavoro. 4 In secondo luogo, ripercorreremo, sinteticamente, le vicende del lavoro coordinato che hanno preceduto l’introduzione della figura delle collaborazioni organizzate dal committente e ciò, per un duplice ordine di considerazioni: da un lato, è la formulazione della norma dell’art. 2 del d.lgs. 81 del 2015 a richiamare elementi di fattispecie delle collaborazioni “autonome” ex art. 409 c.p.c., per cui è ineludibile riferirsi al modello genetico per chiarire il significato e le divergenze della nuova disciplina; dall’altro, da un punto di vista certamente “cronologico” e, come si vedrà, anche “logico”, la disciplina delle collaborazioni organizzate dal committente eredita l’ingrata funzione anti elusiva del lavoro a progetto. Allo scopo di comprendere il terreno elettivo delle collaborazioni etero organizzate, e quindi la “zona grigia”, sarà opportuno spiegare, brevemente, i mutamenti avvenuti nei paradigmi economico – produttivi che hanno contribuito allo scollamento del modo di prestare lavoro rispetto al binomio oppositivo accolto nel nostro codice civile. Allo stesso tempo, si dovrà dare conto delle diverse “stagioni della giurisprudenza” nazionale sulla subordinazione perché, in un sistema a «categorie mutualmente esclusive e complessivamente esaustive», le flessioni di un polo comportano ripercussioni complementari all’altro capo. A questo punto, si affronterà in dettaglio la prima questione del presente elaborato. Si tenterà di delineare i tratti fisionomici delle collaborazioni organizzate dal committente e, conseguentemente, si analizzeranno partitamente i requisiti costitutivi della fattispecie fotografata dal primo comma dell’art. 2 del d.lgs. 81 del 2015: esclusiva personalità della prestazione; continuità ed etero-organizzazione “anche” dei tempi e del luogo della prestazione. Dopo aver qualificato il modo d’essere collaboratori etero organizzati, si potrà affrontare con maggiore consapevolezza la questione dell’inquadramento teorico, non prima però di aver svolto qualche considerazione sulla tecnica legislativa impiegata dal Legislatore. La questione dell’inquadramento teorico delle collaborazioni organizzate dal committente è stata ed è tuttora al centro del dibattito segnalato in apertura, anche a seguito della prima applicazione giurisprudenziale della disposizione. 5 Conseguentemente, non si potrà fare a meno di fornire e incasellare le principali letture proposte dagli operatori del diritto, osservando come le stesse si risolvono, in ultima analisi, nella riconduzione delle collaborazioni ex art. 2 del d.lgs. 81 del 2015 ora all’area del lavoro subordinato ora a quella del lavoro autonomo. A prima vista, siffatta diatriba potrebbe sembrare prima di risvolti pratici posto che, a prescindere da qualsivoglia ricostruzione dogmatica si scelga, alle collaborazioni organizzate dal committente si applicherà, comunque, la disciplina del rapporto di lavoro subordinato come stabilito espressamente dall’art. 2, d.lgs. 81/2015. E, tuttavia, è bene sin d’ora ricordare che secondo alcuni orientamenti, di cui si darà conto, la scelta esegetica inciderebbe in ordine alla selezione delle norme dello statuto del lavoro subordinato concretamente estendibili alle collaborazioni organizzate dal committente. Una volta fornita l’interpretazione “autentica” delle collaborazioni etero organizzate e chiarito il quantum di disciplina della subordinazione che si applica a mente dell’art. 2, si potrà procedere all’indagine sulla seconda questione oggetto del presente elaborato: si metterà l’interpretazione raggiunta alla prova del mondo del lavoro digitale. Specificatamente, si analizzerà il modello operativo ed organizzativo del lavoro prestato nelle piattaforme digitali, identificandone elementi comuni e tratti differenziali sia rispetto al tradizionale lavoro “sconnesso” e sia tra le differenti ed eterogenee realtà che lo “rappresentano”. Si procederà, quindi, a verificare se le tradizionali categorie dell’autonomia e della subordinazione siano in grado di “intercettare” tale fenomeno lavorativo e di produrre un sistema di tutela soddisfacente, sperimentando altresì la nuova disposizione delle collaborazioni organizzate dal committente. Da ultimo, anticipando gli esiti deludenti della verifica sopra tratteggiata, si prenderà posizione sulle tecniche di regolazione del lavoro digitale e sulle modalità di imputazione delle tutele al prestatore di lavoro nella piattaforma.
This thesis aims to address two interrelated research questions. The first one has now become an inescapable intellectual exercise for anybody dealing with the fundamental categories of labor law. Specifically, we allude to the well-known topic of the systematic effects and, before that, of the way of being of the collaborations hetero-organized by the client introduced by art. 2, Legislative Decree n. 81/2015. Indeed, the entire "academy of labor law” has been offering multiple interpretations since the introduction of this legal category without coming to an agreed solution. However, it is now possible to carry out a final synthesis of the doctrine thanks to the privileged view of whom investigates this research question after the "authentic" interpretation provided by art. 15 of Legislative Decree 81 of 2017 and the first rulings. The second research question that we will address concerns the analysis of the provisions governing the hetero-organized work and, specifically, if this new category offers a better (or, at least, sufficient) protection on the new digital work scenarios in comparison with the traditional rights of subordinate work. Article. 2 of Legislative Decree 81/2015, by establishing that "subordinate work protective statute" also "applies" to collaborative work performed continuously and exclusively by an individual worker, providing that the methods of execution are hetero-organized by the client “also in relation to time and place of work”, will intercept the activities falling in the very controversial area of continuous personal work in the interest of a second party. By doing this, this new legal category should address the “ancestral” question of the qualification of the workers performing on the frontier between subordination and autonomy, to which the so called “project work” category had proven not to be able to give an adequate solution. Consequently, we will proceed first to a brief historical analysis of the traditional labor law categories of subordinate work and autonomy against which any new legal category has to be compared. Secondly, we will review the main stages and regulations of the work carried out under a coordinate way with the client that precede the legal category of the collaborations hetero-organized by the client for the following purposes: on the one hand, the legal words used by the art. 2 of Legislative Decree 81 of 2015 inevitably recall requirements of the “old” category of the autonomous collaborations pursuant to art. 409 c.p.c. Therefore, it is mandatory to investigate the “genetic model” to clarify the meaning of the new discipline. On the other hand, both from a "chronological" and "logical" point of view, the provisions for the collaborations hetero-organized by the client “inherit” the anti-elusive spirit and goal of the “project work”. In order to understand the targeted work performances of the hetero-organized collaborations, it will be useful to explain the changes that have taken place in the economic-productive paradigms that have contributed to the detachment of the way of working with respect to the binary system model between subordinate work and autonomy accepted in our civil code. At the same time, we will analyze and categorize the main historical stages of the Italian Jurisprudence on qualification of works since in a system of "mutually exclusive and overall exhaustive categories", the decline of a legal category generates a complementary effect on the other. At this point, the first research question will be discussed in details. We will attempt to outline the key “features” of the collaborations hetero-organized by the client and, consequently, we will analyze the requirements of the work scenario “portrayed” by the first paragraph of art. 2 of Legislative Decree 81 of 2015: an exclusively personal work; continuity and hetero-organization "also" of the time and place of the collaboration. Once identified the key features of the new category, it will be possible to challenge the research question concerning the theoretical framework where the collaborations hetero-organized by the client should fall. To address this question, we will first provide the principal interpretations proposed by the legal practitioners which, eventually, link the new category of the collaborations pursuant to art. 2 of Legislative Decree 81 of 2015 to one of the traditional binary categories of subordinate work or self-employment. At first glance, such radical opposition does not seem to yield any practical implications given that, the collaborations hetero-organized by the client will be ruled according to the provisions set for subordinate work as established expressly by the art. 2, Legislative Decree 81/2015. Nevertheless, it has to be acknowledged that according to some doctrines the theoretical framework choice affects the provisions that can be concretely extended to the collaborations hetero-organized by the client. Once provided the "authentic" interpretation of the new legal category and clarified the “quantum” of discipline of the subordination work that applies to hetero-organized works as per art. 2, it will be possible to proceed with the second research question: we will test the new category against the digital work scenario. Specifically, we will analyze the operational and organizational model of the work performed within a “digital work platform”, identifying common elements and differential traits with respect to both traditional "offline-work” and all the multiple forms in which the digital works take place. We will therefore proceed to verify if the traditional binary categories of autonomy and subordination are able to "intercept" and “qualify” this recent work phenomenon and contribute to a fair protection of digital workers. Finally, anticipating the disappointing outcomes of the above mentioned investigation, we will take a position on digital job regulation techniques thus suggesting a possible way to protect the employee in the working platforms.

Multiplayer online battle arena (MOBA) games have properties that make them suitable for research in artificial and computational intelligence. MOBA games are generally played team vs team meaning planning and organizing the team is one of the most important aspects. This makes it suitable for research in artificial intelligence agent cooperation. This paper presents a literature review performed in the area of artificial and computational intelligence regarding MOBA games. The findings are that there is little or no research made in the area. The research found concerning MOBA games is in the context of player behaviour and toxic behaviour in the MOBA game league of legends. What is found is encouragement on developing frameworks supporting 5v5 matches in MOBA games which this paper also presents, a 5v5 framework for bot-matchmaking in DotA 2 making it possible for users to develop bots to be run versus the in-game AI.

Mobile robotics has become a rapidly developing field of interdisciplinary research within robotics. This promising field has attracted the attention of academicy, industry, several government agencies. Currently from security to personal service mobile robots are being used in a variety of tasks. The use of such robots is expected to only increase in the near future. In this study, it is aimed to design and manufacture a versatile robot base. This base is aimed to be the main driving unit for various applications performed both indoors and outdoors ranging from personal service and assistance to military applications. The study does not attempt to individually address any specific application, indeed it is aimed to shape up a robotic module that can be used in a wide range of application on different terrain with proper modification. The robot base is specifically designed for mixed terrain applications, yet this study attempts to provide some guidelines to help robot designers. The manufactured robot base is tested with tracks, wheels, and with both tracks and wheels, results are provided as guidelines to robot designers. Last but no the least, this study aims to obtain the know-how of building functional and flexible robots in Turkey by facilitating local resources as much as possible.

In this study the design of the sanitary ware and bathrooms are examined, concentrating on small bathrooms and changing design aspects of bathrooms. The design considerations of bathrooms and the design of the bath tub, wash basin and toilet which forms the sanitary ware sets in bathrooms is reviewed as for being dominant elements of bathroom design.

In this study, it is aimed to relate architecture with the changing definitions of territory. In this context, the research will focus on the issue of in-between, where the boundaries between public and private domains are blurred in the modern world. The Dutch Embassy in Berlin designed by OMA / Rem Koolhaas is built upon a creative redefinition of blurring boundaries between &
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. Given the fact that the Embassy is a diplomatic structure for which the safety factor is one of the most important design criteria, how Koolhaas interprets the idea of openness, of transparency, modernity which are meant to symbolize the Netherlands, will be studied in this research.

In this study, the geometric Additive market models are considered. In general, these market models are incomplete, that means: the perfect replication of derivatives, in the usual sense, is not possible. In this study, it is shown that the market can be completed by new artificial assets which are called &ldquo
power-jump assets&rdquo
based on the power-jump processes of the underlying Additive process. Then, the hedging portfolio for claims whose payoff function depends on the prices of the stock and the power-jump assets at maturity is derived. In addition to the previous completion strategy, it is also shown that, using a static hedging formula, the market can also be completed by considering portfolios with a continuum of call options with different strikes and the same maturity. What is more, the portfolio optimization problem is considered in the enlarged market. The optimization problem consists of choosing an optimal portfolio in such a way that the largest expected utility of the terminal wealth is obtained. For particular choices of the equivalent martingale measure, it is shown that the optimal portfolio consists only of bonds and stocks.

Self compacting concrete (SCC) is first developed in Japan in the late 1980s in order to overcome the consolidation problems associated with the presence of congested reinforcement. It is also termed as a high performance concrete, as it can flow under its own weight and completely fill the formworks. As the fresh properties of SCC are quite important, mix design of a SCC is performed by considering various workability related fresh properties. Therefore, a well designed SCC should satisfy all requirements of a hardened concrete, besides its superior workability properties. The aim of this research is to assess the effects of some basic ingredients of SCC on the fresh properties of SCC. This will be performed by applying design of experiment techniques and obtaining significant statistical models, which will give valuable information about the effects of the model parameters on the rheology and fresh state characteristics of SCC. In this research program, four different variables
use of fly ash replacement, use of high range water reducing admixture (HRWRA), use of viscosity modifying admixtures (VMA) and water-cementitious material ratio, are considered as the variables of the experimental design. Central Composite Design (CCD), a design of experiment technique, is employed throughout the experimental program and a total of 21 mixtures of concrete are cast. Slump flow, V-funnel, L-box, sieve segregation, initial and final setting time tests are performed, furthermore
to investigate the effects of these variables to the rheology of SCC, relative plastic viscosity and relative yield stress, which are the parameters of Bingham Model are measured with the help of a concrete rheometer. As a result of the experimental program, the fresh state properties of SCC are expressed by mathematical equations. Those equations are then used in order to explain the effects of fly ash replacement, HRWRA and VMA concentration, and the w/cm ratio on the fresh state properties of SCC. According to the derived models, it is stated that the water-cementitious material ratio of the concrete mixture is the most effective parameter on the flowability and passing ability of SCC beside the other parameters utilized in this research as its coefficient was the highest in the related models.

In this thesis, the measurement uncertainty of Coordinate Measuring Machine (CMM) is analysed and software is designed to simulate this. Analysis begins with the inspection of the measurement process and structure of the CMMs. After that, error sources are defined with respect to their effects on the measurement and then an error model is constructed to compensate these effects. In other words, systematic part of geometric, kinematic and thermal errors are compensated with error modelling. Kinematic and geometric error model is specific for the structure of CMM under inspection. Also, a common orthogonal kinematic model is formed and with using the laser error data of the CMM and error maps of the machine volume is obtained. Afterwards, the models are compared with each other by taking the difference and ratio. The definition and compensation of the systematic errors leave the uncertainty of measurements for analysing. Measurement uncertainty consists of the uncompensated systematic errors and random errors. The other aim of the thesis is to quantify these uncertainties with using the different methods and to inspect the success of these methods. Uncertainty budgeting, comparison, statistical evaluation by designing an experiments and simulation methods are examined and applied to the CMM under inspection. In addition, Virtual CMM software is designed to simulate the task specific measurement uncertainty of circle, sphere and plane without using the repeated measurements. Finally, the performance of the software, highly depending on the mathematical modelling of machine volume, is tested by using actual measurements.

Autoinducer 2 (AI-2) molecules produced by bacterial cells are thought to be involved in controlling a variety of bacterial cellular processes by coordinated gene and protein expression. Previous work in our laboratory has shown that ground beef contains compounds that can interfere with AI-2-mediated bioluminescence expression in Vibrio. harveyi. The underlying hypothesis of this work was that AI-2 molecules affect the protein expression in Escherichia coli O157:H7 and AI-2 inhibitory molecules negate the influence of AI-2 molecules. The main objectives of this study were to identify, characterize, and isolate the factors responsible for inhibition of AI-2 molecules from ground beef extracts, elucidate the role of LuxS/AI-2 cell signaling system in E. coli O157:H7 protein expression, and determine if inhibitory factors present in ground beef extract can negate the influence of AI-2 molecules on the protein expression. Using a solvent extraction procedure and gas chromatography analysis, AI-2 inhibitory factors present in ground beef extracts were identified as both medium and long chain fatty acids. When identified fatty acids were tested at different concentrations for AI-2 inhibition, AI-2 inhibition ranging from 25% to 90% was observed. Both ground beef extracts and mixture of selected fatty acids also resulted in 2- to 4-fold reduced AI-2 influenced biofilm formation by E. coli K12 cells. Identification of LuxS/AI-2-mediated protein expression in E. coli O157:H7 was conducted using two dimensional gel electrophoresis. Protein expression analysis showed that the LuxS/AI-2 system modulates the expression of proteins involved in different cellular processes such as carbohydrate and amino acid metabolism, stress response, and formation of flagella and motility. When AI-2 inhibitory factors were added along with AI-2 molecules, the expression patterns of three AI-2-influenced proteins (GlmS, SpeE, and NikA) were changed suggesting that AI-2 inhibitors can negate the influence of AI-2 molecules on protein expression of selected proteins. Collectively, these results highlight that proteins associated with different cellular processes in E. coli O157:H7 can be modulated depending on whether cells are in contact with AI-2 molecules in the presence or absence of AI-2 inhibitory factors.

Bacteria produce and respond to external stimuli using molecules termed autoinducers. Poultry meat contains inhibitors which interfere with AI-2 signaling. The primary objective of this work was to understand the effects of AI-2 on the virulence and growth of Salmonella Typhimurium, and if the introduction of AI-2 inhibiting compounds would influence these effects. Using DNA microarray analysis, expression of 1136 virulence-related genes in a Salmonella Typhimurium wild type and a luxS mutant strain, PJ002 (unable to produce AI-2), was monitored after exposure to treatments containing in vitro synthesized AI-2 (AI-2) and poultry meat (PM) inhibitors. Responding gene expression was unique in the presence of AI-2, with 23 genes differentially expressed at least 1.5-fold (p < 0.05). The combined AI-2 + PM treatment resulted in 22 genes being differentially expressed. Identification of inhibitory compounds was attempted using GC analysis on a hexane solvent extract obtained from a PM wash. From this analysis, chemical standards of linoleic, oleic, palmitic, and stearic acid were tested for inhibition using V. harveyi BB170. Combined fatty acids (FA) demonstrated inhibition against AI-2 at 60 % while 10-fold and 100-fold concentrations had inhibition of 84 % and 70 %, respectively. Growth of PJoo2, was studied using M-9 minimal medium with FA of varying concentrations, supplemented with either AI-2, or 1X phosphate buffered saline (PBS). Comparative analysis was done calculating the growth constants based on OD 600 values for each treatment. No significant difference in the combined FA + AI-2 treatments was observed against the AI-2 treatment. A significant increase in the growth rate constants of the AI-2 treatments was observed, however, compared to the PBS control (P = 0.01). Bacterial invasiveness, using a murine macrophage cell line, RAW 264.7, was also studied. AI-2 decreased cell invasiveness (P = 0.02), while the addition of combined FA improved invasiveness to normal levels. The results of these studies indicate that AI-2 does have an effect on the growth and virulence of Salmonella, but this is not uniformly modulated by the introduction of fatty acids, that inhibit AI-2 activity, suggesting that inhibition may be based on species specific transport systems.

碩士
國立清華大學
分子醫學研究所
96
Quorum sensing is a phenomenon with which bacteria detect high population density and change their phenotype. Bacteria secrete some signal molecules called autoinducer, then detect autoinducer concentration to achieve quorum sensing. Autoinducer-2 (AI-2) is a signal molecule in common use among many bacterial species, and it is synthesized by LuxS . If there is a luxS gene in a bacterial genome, the bacteria may secrete the AI-2. Lactobacillus casei ATCC 334 is a lactic acid bacteria of which the genome has been sequenced completely. It has luxS gene, and AI-2 activity can be detected . In order to study which phenotype is controlled by AI-2 in Lactobacillus casei ATCC 334, we directly added AI-2 to incubate Lactobacillus casei ATCC 334. We purified recombinant protein LuxS and used it to synthesize AI-2 for purification. We used GC-MS and NMR proton spectrum to determine whether the enzyme product was AI-2. We tested the effects of AI-2 on three phenotypes：biofilm、antibacterial ability and antioxidative ability. There is no significant difference.

Relatório de Estágio do Mestrado Integrado em Ciências Farmacêuticas apresentado à Faculdade de Farmácia
A resistência bacteriana a antibióticos é dos problemas que mais preocupa ossistemas de saúde a nível mundial. Sendo que, a velocidade de desenvolvimento desta émaior que a de aparecimento de novos antibióticos, surge, assim, a necessidade de encontrarnovas abordagem para prevenir e tratar doenças infeciosas causadas por bactérias.O Quorum Sensing (QS) é um processo que permite que as bactérias comuniquementre si, podendo, assim, sincronizar o seu comportamento com base na densidadepopulacional. Sendo que, a comunicação é possível devido a pequenas moléculassinalizadoras, denominadas de auto-indutores (AI). Os AIs mais comum, nas bactérias Gramnegativo, são as acil-homosserina lactonas e, nas bactérias Gram, positivo são os peptídeosauto-indutores. No entanto, existe um AI universal, descrito tanto em bactérias Gramnegativo como Gram positivo: o auto-indutor-2 (AI-2).Estes diferentes sistemas de QS regulam a expressão de vários genes, culminando emalterações fenotípicas, que se encontram intimamente relacionadas com a patogenicidade dasbactérias. Assim, um maior conhecimento destes sistemas permitirá o desenvolvimento denovas terapias que interfiram com a comunicação, e, consequentemente, com o decurso dainfeção.Vários são os alvos existentes no sistema de QS dependente de AI-2 para oscompostos inibidores. No entanto, estes não se encontram diretamente relacionado comprocessos essenciais ao crescimento das bactérias, o que faz com que a pressão seletivaexercida por estas abordagens seja baixa. Assim, é expectável que a velocidade dedesenvolvimento de resistência seja menor do que a que se registou para os antibióticostradicionais.Muitos compostos sintéticos e naturais têm sido descritos como inibidores dosistema de QS dependente de AI-2, sendo que os mecanismos de ação de alguns já sãoconhecidos. Existe ainda muito trabalho a fazer nesta área mas estas são abordagens têmmuito potencial.
Drug resistance in bacteria is one of the most concerning problems for health caresystems worldwide. Since the speed of drug resistance’s emergence is greater than that ofdevelopment of new antibiotics, there is a need to find new approaches to prevent and treatbacterial infectious diseases.Quorum Sensing (QS) allows bacteria to communicate with each other andsynchronize their behavior based on their population density. Communication is due to smallsignaling molecules: the autoinducers (AI). The most common AIs, in Gram negative bacteria,are acylhomoserin lactones and, in Gram positive bacteria, are autoinducing peptides.However, there is a universal AI, described both in Gram negative and Gram positivebacteria: Autoinducer-2 (AI-2).The differents QS systems regulate the expression of several genes, which leads tophenotypic changes that are closely related to the pathogenicity of bacteria. Thus, a greaterknowledge of these systems will allow the development of new therapies that interfere withcommunication and, consequently, with the course of the infection.AI-2 quorum sensing have several targets. However, these are not directly related toessential processes to the growth of bacteria, which means that the selective pressureexerted by this approach is low. Thus, the speed of development of resistance will be lessthan that registered for traditional antibiotics.Many synthetic and natural compounds have been described as inhibitors of the AI-2--QS system, and some the mechanisms of action are already known. There is still a lot ofwork to do in this area but these are very promising approaches.

Tese de mestrado, Biologia (Biologia Evolutiva e do Desenvolvimento), 2009, Universidade de Lisboa, Faculdade de Ciências
O intestino de mamíferos é habitado por comunidades de bactérias residentes. Apesar de muitas das espécies já terem sido identificadas, os mecanismos que permitem o seu estabelecimento e a sua permanência são em grande parte desconhecidos. A espécie Escherichia coli é uma das primeiras a colonizar o intestino de mamíferos. As bactérias desta espécie podem comunicar entre si pela produção e secreção de moléculas que são detectadas por biossensores de densidade celular. Uma destas moléculas, o autoindutor- 2 (AI-2), é sintetizado e pode ser detectado por um grande número de espécies bacterianas. A detecção de AI-2 leva à expressão de genes importantes para a colonização de novos habitats, como aqueles que estão envolvidos na formação de biofilmes. Apesar de alguns estudos mostrarem que a detecção de AI-2 influencia o desenvolvimento da virulência de bactérias patogénicas, a influência deste sistema em bactérias não patogénicas permanece por explorar. Assim, procurou-se avaliar se a produção de AI-2 por estirpes não patogénicas de E. coli teria alguma influência na colonização do ambiente intestinal de ratinhos, e se estas bactérias apresentariam uma vantagem adaptativa durante o processo de colonização relativamente a mutantes que não produzem o sinal. Ratinhos foram inoculados com uma estirpe selvagem de E. coli, uma estirpe mutante que não consegue produzir o sinal AI-2, e com uma mistura 1:1 destas duas estirpes. O número de bactérias inoculadas presente nos intestinos dos animais foi determinado ao longo de quatro dias após tratamento do conteúdo das fezes através de um protocolo desenvolvido. Os resultados obtidos mostram que não houve diferenças significativas entre os níveis de colonização das estirpes inoculadas. Apesar destes resultados favorecerem a hipótese de que os biossensores de AI-2 de E. coli não são importantes para a colonização, serão discutidas outras explicações relacionadas com as especificidades dos sistemas de detecção de AI-2.
Mammalian intestines are populated by resident bacterial communities. Although many of these species have already been identified, the mechanisms by which they establish themselves in the intestines and persist throughout time are to a great extent unknown. Escherichia coli is one of the first species to colonize this environment. These bacteria can communicate by producing and secreting molecules which are in turn detected by their quorum-sensing systems. One of these molecules, the autoinducer-2 (AI-2), is synthesized and can be sensed by bacteria from a high number of species. This detection leads to the up-regulation of important genes for the colonization of new habitats, like the ones involved in biofilm assembling. Even though several studies show that AI-2- mediated quorum-sensing influences the virulence of pathogenic bacteria, its influence in non-pathogenic bacteria remains yet to be determined. In order to address this question, experiments were conducted to determine if AI-2 production by nonpathogenic E. coli strains would influence their colonization process in mice intestines, and if these bacteria would present any adaptive advantage during this colonization process in comparison with mutants which do not produce AI-2. Mice were either colonized with a wild-type E. coli strain, a mutant strain unable to produce AI-2 or a 1:1 mixture of the two above mentioned strains. Numbers of inoculated bacteria that were present in mice intestines were determined during four days by processing feces using a protocol developed for that end. There were no significant differences between the colonization levels of all inoculated strains. Even though the results favour the non essentiality of E. coli AI-2-mediated quorum-sensing systems for intestinal colonization, other hypotheses will be discussed that account for the idiosyncrasies of this specific quorum-sensing system.

The overall goal of this research was to understand the role of inter-kingdom signaling in enterohemorrhagic Escherichia coli (EHEC) infections of the human gastro-intestinal (GI) tract from the perspective of both the invading pathogen and the human intestinal epithelial cells, which they colonize. Differential gene expression of EHEC was studied upon exposure to the human neuroendocrine hormones epinephrine and norepinephrine. We determined that these hormones increase EHEC chemotaxis, motility, biofilm formation, colonization of host cells, and virulence gene expression. We also studied the EHEC response to the GI tract commensal bacterial signaling molecules indole and autoinducer-2 (AI-2). We observed that indole decreases all the EHEC phenotypes that are increased by the human hormones and represses EHEC virulence. However, the effect of AI-2 was similar to that observed with hormones and opposite to that observed with indole, i.e. AI-2 increases EHEC virulence phenotypes. We studied changes in host cell transcriptome in the presence of the commensal bacterial signal indole. Indole increases expression of genes involved in tight junction and gap junction formation, and production of mucins and actin cytoskeleton genes. Indole also down-regulates genes encoding for pro-inflammatory cytokines, chemokines, and Toll-like receptors. The gene expression results were confirmed with phenotypic assays where we observed an increase in trans-epithelial resistance, increase in the anti-inflammatory cytokine IL-10, decrease in the pro-inflammatory cytokine IL-8, decrease in the activity of the pro-inflammatory transcription factor NF-κB, and decrease in colonization by EHEC of the indole-pre-treated HCT-8 cells. We established that factors secreted by epithelial cells are important determinants of EHEC virulence. Gene expression studies showed that 34 out of 41 LEE virulence genes were induced when EHEC was cultured in conditioned medium. In addition, the data showed increased expression of the shiga toxin-2 prophage 933W. These changes in gene expression were corroborated by a 5-fold increase in HCT-8 cell colonization and increased intracellular Stx2 phage titers. We determined that the HCT-8-secreted factor(s) was protein-based and that it was greater than 3 kDa in size. In conclusion, we have characterized the pathogen response to various eukaryotic and prokaryotic GI tract signals. We have established, for the first time, that the commensal bacterial signal indole is an inter-kingdom signal for the host epithelial cells. Overall, our studies provide a greater understanding of host-pathogen interactions.

碩士
國立臺北科技大學
建築與都市設計研究所
99
In recent years people have higher demand of the quality of living environment, and a proper balcony space is supposed to be the place where inhabitants can get in touch with nature, thus enhancing the quality of their living. But the growth of population that accompanies the fast growth of cities results in the rise of traffic, which in turn brings noise pollution that seriously damages the quality of living for those whose houses sit alongside the road. Urban balconies are therefore categorized as subsidiary decorations and fail to exert their original function. The target of this research is the balcony space on the 3rd floor, 95-2, 2nd sec., Ren-ai Road, Taipei. Via literature discussion and analysis of conditions of the present base, this research concludes 12 attributes and ‘the social intercourse garden reciprocating the treed boulevard’ as its design concept. Its spatial design strategy of situation transformation, which applies techniques including balcony based noise test, noise transmission test, theoretical analysis of road noise barrier and Cadna-A simulation to decide the height of railings, 120cm, and proper decoration materials, reduces the noise and enlivens the space of the balcony.

The mammalian gut microbiota is a complex and diverse community composed of many bacterial species and other unicellular organisms. Gut bacteria play essential functions impacting many aspects of host health, but are also influenced by the host through diet, lifestyle, and antibiotics use. Antibiotics compromise the balanced microbiota composition, resulting in dysbiosis. Previous results from our group showed that bacterial signalling, mediated by quorum sensing, can be used to promote microbiota recovery after disturbances. Interspecies quorum sensing allows bacteria from different species to communicate through the autoinducer-2 (AI-2) signal, and we showed that by boosting AI-2 levels it is possible to accelerate microbiota recovery after long antibiotic-induced dysbiosis. Here, we studied members of the Barnesiella and Muribaculum genera, which are highly abundant in the homeostatic gut, but were shown to be greatly affected by antibiotics. Additionally, we have evidence that they respond to AI-2 in vivo. We aim to characterize these bacteria and identify respective AI-2-regulated phenotypes. We focused on the utilization of fucosylated compounds since previous work provides evidence for AI-2-mediated regulation of fucosidases in a closely related bacterium. Additionally, we also studied the impact of AI-2 and of Muribaculum intestinale colonization on microbiota recovery after short antibiotic treatment. To study AI-2-regulated functions in Barnesiella intestinihominis, Barnesiella viscericola, and Muribaculum intestinale, growth conditions and PCR-based assays were optimized to identify these species. A Peptone Yeast extract-based broth was modified to test carbon source supplementation and assess bacterial growth in fucosylated compounds with or without added synthetic AI-2. Our results show that B. intestinihominis and M. intestinale consume these fucosylated compounds and provide preliminary evidence that their growth in these compounds might be influenced by AI-2. Lastly, our results in a mouse model of short antibiotic treatment, show that increasing AI-2 levels promotes faster recovery of gut microbiota diversity from dysbiosis.

Este tiempo y espacio compartidos nos llevaron a valorar la producción conjunta como una nueva posibilidad en nuestro hacer de artistas, hasta ahora siempre individual. Al inicio del 2020 habíamos comenzado a considerar hacer nuestro Trabajo Final en grupo, como algo viable y enriquecedor para ambas. Y luego llegó la pandemia del COVID-19, el aislamiento, la vida en cuarentena, las salas y los museos cerrados tuvieron la última palabra. Decidimos hacer de esta circunstancia una oportunidad y aprovecharla para generar nuestro proyecto, aprovechando el recurso de la conexión en línea y las redes sociales. Nos animamos a desarrollar esta experiencia artística en un ámbito en el que antes no habíamos incursionado: la virtualidad. Nuestra propuesta es el desarrollo de una instalación virtual, configurada con el aporte colectivo de amigos, conocidos, familiares, compañeros y profesores de la carrera, artistas, y cualquier otra persona que respondió a la convocatoria de enviarnos una foto o un video de alguna experiencia personal.
Fil: Geisa, Magali Ailen. Universidad Nacional de Córdoba. Facultad de Artes. Departamento Académico de Artes Visuales; Argentina.
Fil: Peyrano, Andrea Luz. Universidad Nacional de Córdoba. Facultad de Artes. Departamento Académico de Artes Visuales; Argentina.