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Avalia??o do desempenho da parede celular de leveduras como aditivo anti-micotoxinas na intoxica??o experimental por aflatoxina, zearalenona ou fumonisina / Evaluation of yeast cell wall as antimycotoxin additive on experimentall intoxication by aflatoxin, zearalenone or fuminosinPERALI, Christianne 29 March 2016 (has links)
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Previous issue date: 2016-03-29 / Brazilian pig farming is among the most important in the world. Brazil is always ranks as one of the leading exporters of this and other meats, as well as its important role in grain production. In the last decade, society in general has been increasingly concerned with the quality of food consumed not only by humans but also for animals that produce human food. Thus, mycotoxins have become a concern for all governments around the world, enacting restrictions and limits for the presence of these compounds in almost all food products, especially those from other countries. The scientific community has been searching for affordable and social and environmentally correct alternatives to minimize the adverse effects of these toxins. In this sense, the yeast cell wall (YCW), especially from Saccharomyces cerevisiae has been identified as one of the most promising alternatives. So, three experiments were developed to evaluate the ability of yeast cell wall in controlling the negative effects of three mycotoxins separately, aflatoxin B1 (AFB1), zearalenone (ZEA) and fumonisin B1 (FB1). Were evaluated: organic parameters (body weight, liver relative weight, kidneys relative weight, liver enzymes, urea and creatinine, among others), production parameters (weight gain, feed intake and feed conversion) and for AFB1 and ZEA also carcass quality parameters and meat quality. In Chapter 1 is presented a brief review of main issues inherent to the subject, as the production of Brazilian grain, Brazilian pork production, mycotoxins and their effects and, finally, the anti-mycotoxin additives and yeast cell wall. Chapter 2, 3 and 4 respectively presents the results of the above parameters obtained in each experiment that evaluated the PCL's ability to control the negative effects of AFB1 (Cap.2), ZEA (chapter 3) and FB1 (cap.4 ). After these evaluations, it was concluded that the studied PCL was able to control the negative effects of the three mycotoxins in the concentrations evaluated. / A suinocultura brasileira est? entre as mais importantes do mundo. O Brasil est? sempre figurando como um dos maiores exportadores mundiais desta e de outras carnes, al?m de seu important?ssimo papel na produ??o de gr?os. Na ?ltima d?cada, a sociedade de forma geral vem se preocupando cada vez mais com a qualidade dos alimentos consumidos n?o apenas pelo homem, mas tamb?m pelos animais que produzem o alimento humano. Assim, as micotoxinas passaram a ser uma preocupa??o de todos os governos ao redor do mundo, decretando restri??es e limites para a presen?a destes compostos em quase todos os produtos aliment?cios, em especial naqueles provenientes de outros pa?ses. A comunidade cient?fica vem buscando alternativas economicamente vi?veis e social e ambientalmente corretas para minimizar os efeitos nefastos destas toxinas. Neste sentido, a parede celular de leveduras (PCL), especialmente da Saccharomyces cerevisae vem sendo apontada como umas das alternativas mais promissoras, assim, no presente trabalho foram desenvolvidos tr?s experimentos objetivando avaliar a capacidade da parede celular de levedura em controlar os efeitos negativos de tr?s micotoxinas isoladamente, a saber, aflatoxina B1 (AFB1), zearalenona (ZEA) e fumonisina B1 (FB1), quando foram avaliados par?metros org?nicos (peso vivo, peso relativo do f?gado, peso relativo dos rins, enzimas hep?ticas, ur?ia e creatinina, entre outros), par?metros produtivos (ganho de peso, consumo de ra??o e convers?o alimentar) e, para AFB1 e ZEA tamb?m par?metros de qualidade de carca?a e de carne. No cap?tulo 1 est? apresentada uma breve revis?o de literatura que aborda os principais assuntos inerentes ao tema, como a produ??o de gr?os brasileira, situa??o da suinocultura nacional, as micotoxinas e seus efeitos e, finalmente, os aditivos anti-micotoxinas e a parede celular de leveduras. No cap?tulo 2, 3 e 4 est?o apresentados os resultados dos par?metros acima descritos obtidos no experimento que avaliou a capacidade da PCL em controlar os efeitos negativos respectivamente da AFB1 (cap.2), ZEA (cap.3) e FB1(cap.4). Ap?s estas avalia??es, concluiu-se que a PCL estudada foi capaz de controlar os efeitos negativos das tr?s micotoxinas estudadas, nas concentra??es avaliadas.
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Investigations of HP1 and insulator partner protein 1 (HIPP1)Glenn, Steve Ehren 01 December 2018 (has links)
Drosophila HP1 and Insulator Partner Protein 1 (HIPP1) is the homologue of the human co-repressor Chromodomain Y family of proteins that repress neuronal gene expression in mammals. HIPP1 was identified by its extensive co-localization with Heterochromatin Protein 1a (HP1a) in heterochromatic regions of the genome and insulator binding proteins in euchromatic regions. The majority of HIPP1 binding to euchromatin is at binding sites for Drosophila Suppressor of Hairy-wing [Su(Hw)]. Su(Hw) is a zinc finger DNA binding protein that functions as an insulator, activator, and repressor. Transcriptional regulation by Su(Hw) is essential in the ovary and testis, where Su(Hw) functions primarily as a repressor of neuronal genes. However, the mechanism of Su(Hw) dependent repression is not clear. The focus of my thesis work has been defining the role of HIPP1 in development and its contribution to Su(Hw) function and heterochromatin formation. As part of this work, CRISPR was used to generate multiple Hipp1 null alleles and a tagged derivative of the endogenous gene (Hipp1GFP). Hipp1 null flies were found to be viable. Study of HIPP1 expression revealed it is present in most tissues and restricted to the nucleus. HIPP1 showed limited colocalization with HP1a, and tests of repression of transgenes in heterochromatin suggested that HIPP1 is not required for heterochromatin formation. Investigations of HIPP1 binding revealed that Su(Hw) is responsible for the majority of HIPP1 recruitment to euchromatin. Despite this, HIPP1 was found to be dispensable for the transcriptional and insulator functions of Su(Hw) as well as for female and male fertility. These data indicate that HIPP1 is not a critical Su(Hw) cofactor. Further studies are needed to clarify the role of HIPP1 in Drosophila development.
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冷戰後俄國軍售蘇愷戰機之研究:1992-2011 / The Study of Russian Sukhoi Fighter Sales after Cold War:1992-2011王洪謙, Wang, Hung Chien Unknown Date (has links)
由於蘇聯的解體導致冷戰結束,原本由東西兩方所撕裂的世界對立已然消
失,正所謂「飛鳥盡,良弓藏,狡兔死,走狗烹」,原本用來阻止敵對勢力侵犯的軍隊自然面臨大量裁軍與刪除鉅額預算的困境。這種情況在冷戰剛結束後的世界各國皆如此,美國四個軍種都各自終止諸多高科技武器的研發項目,並大量裁減軍隊規模,歐洲亦然,而俄國的情況更惡劣,金融方面不僅缺乏稅收,盧布也巨幅貶值,不僅軍隊的薪餉無法發放,連裁退老舊武器的資金都還得靠西方國家資助,俄國軍隊面對前所未遇的巨大難關。
同時,俄國的軍工複合體也缺乏資金,面臨無以為繼的情況。不過此時有
個巨星從破敗的俄國軍工複合體中出現,就是-Su-27 家族戰機。
由上述假設命題衍生出來下列邏輯相關的子命題:
(一)為何蘇愷戰機能得到冷戰後國際軍火市場的青睞?
(二)冷戰後外銷蘇愷戰機所得之外匯對於俄國經濟有何影響?
(三)冷戰後外銷蘇愷戰機所得之外匯對於俄國航空工業之影響為何?
(四)蘇愷戰機的外銷在冷戰後的俄國對外政策中扮演何種角色?
(五)綜合以上,可得到什麼結論?
Su-27 家族戰機是蘇聯在解體之前所完成開發的兩種第四代戰機之一,而且Su-27 家族是屬於重型戰機分類,所以無論在航程、武裝搭載量上都遠勝輕型戰機甚多,同時又因為Su-27 的先天不穩定設計,使Su-27 家族的機動性大幅提高,更重要的是Su-27 家族來自幣值與消費水準相對低的俄國,使的造價也相對低廉,再者,俄國相對於美國在出售武器方面的政治限制也較低,在以上諸多因素的交互作用之下,Su-27 便暢銷世界,成為冷戰後俄國軍工產業對外軍售最成功的產品之一,俄國軍機產業也因此保存了下來。因此本文將探討為何Su-27 能在如此艱困的大環境下還能如此逆勢成長。 / The collapse of the Soviet Union means the Cold War ends. The opposition between the East and the West had been disappeared. There is so called " when the fish is caught ,
the net is laid aside." So all the arming forces of each country were facing the reduction inquantity and in the budget. For example, all types of American arming forces were ended a lot of R&D plans and disarmament, and the European countries were facing the same situation. In Russia, the situation became much worse than the West. Not only lack of financial taxes support, the depreciation of the ruble was also huge. Let the salary of the military troopers could not be issued. And the Russian government was also lack ofmoney to retire the expired weapons. Russian troops faced an unprecedented dilemma.
Meanwhile, the military industrial complex of Russia was also lack of funds. Butthere was a super star rising from the ashes, it was the Su-27 Flanker family.
This thesis will explore why the Su-27 family could become one of the best-selling fighters of the world in the post-Cold War period.
Propositions derived from the above assumptions the following logical propositions:
(A) Why the Sukhoi fighters could be one of the best-selling fighters in the international arms market in the post-Cold War period?
(B) The foreign exchange earnings from the selling the Sukhoi fighters brings what kind of influence to the Russian economy?
(C) The foreign exchange earnings from the selling the Sukhoi fighters brings what kind of influence to the Russian aviation industry?
(D) The export of the Sukhoi fighters in the post-Cold War plays what kind of role in the Russian foreign policy?
(E) What can we conclude from the above questions?
The Su-27 Flanker family belongs to the class of heavy fighter, it has high performance and less cost compare to the Western products. And the most important is, Russia could sell it to all countries which wants to buy it. Russian government realized the potential political power of the Su-27 family so it decided to put it into the international arms market. The interaction between government and the technicaladvantage of the Su-27 family makes the Su-27 family become one of the best-selling fighters in the world.
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Conception et réalisation d'un bio-microsystème basé sur la diélectrophorèse et l'électrofusion en vue de l'immunothérapie du cancerMottet, Guillaume 14 September 2009 (has links) (PDF)
Notre sujet de recherche vient d'une demande de cliniciens pour obtenir en grande quantité des hybridomes issus de la fusion entre cellules cancéreuses et cellules dendritiques. Ces travaux s'insèrent dans la recherche contre le cancer par un procédé proche de la vaccination, appelé immunothérapie du cancer. Il existe actuellement des dispositifs commercialisés, mais ceux-ci ne parviennent pas à produire de façon importante des hybridomes de qualités. L'idée était donc de se placer à l'échelle des cellules, pour interagir sur elles de façon précise, tout en bénéficiant de la miniaturisation pour contrôler un grand nombre de cellules en parallélisant le dispositif. Restait à choisir quelles forces utiliser pour agir sur les cellules pour les déplacer, les placer et les fusionner, car à l'échelle microscopique le rapport des forces sont différents de ceux à notre échelle. Nous avons opté pour l'emploi de la microfluidique pour le transport des cellules, de la diélectrophorèse pour les positionner et de l'électrofusion pour les fusionner. Ce projet est à la conjonction de savoir-faire dans les domaines de la microtechnologie, de l'interaction champs électriques-cellules et de la biologie cellulaire.
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Microtechnologies polymères pour les laboratoires sur pucesAbgrall, Patrick 07 February 2006 (has links) (PDF)
Linvention du concept de µTAS (micro total chemical analysis system) au début des années quatre vingt dix a ouvert aux fluides la porte du monde des microsystèmes. Un laboratoire sur puce intègre toutes les fonctions dun laboratoire macroscopique (déplacer, mélanger, chauffer des liquides, filtrer, séparer, détecter des molécules, etc.) sur une petite surface (typiquement quelques centimètres carrés). Le challenge technologique repose sur le couplage entre un microsystème conventionnel et un réseau microfluidique. Si les procédés silicium et verre ont été largement utilisés durant les années quatre vingt dix, ils présentent plusieurs inconvénients rédhibitoires : incompatibilité des technologies silicium avec les forts champs électriques nécessaires pour les séparations électrophorétiques et/ou le pompage électroosmotique, technologies non adaptées pour des grandes surfaces, difficultés dintégration dans un système complet, prix élevé des matériaux et des procédés associés, etc. La solution explorée dans cette thèse consiste à construire directement le réseau microfluidique sur un microsystème conventionnel dans des résines photosensibles (SU-8), ce qui facilite lintégration et autorise la fabrication de structures 3D avec un excellent alignement niveau à niveau. Les outils de caractérisation microfluidique développées et utilisés dans le cadre de ce travail sont présentés. Les effets de surface étant fondamentaux à cette échelle, une stratégie générique de modification des propriétés physicochimiques de la SU-8 est proposée et caractérisée.
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Torsion de Reidemeister non abélienne et forme volume sur l'espace des représentations du groupe d'un noeudDubois, Jérôme 10 October 2003 (has links) (PDF)
Pour un n\oe ud $K$ dans $S^3$, on construit dans l'esprit de Casson -- et plus précisément en s'inspirant des travaux ultérieurs de Lin (cf. J. Differential Geom. 35 (1992) 337-357) et Heusener (cf. Topology Appl. 127 (2003) 175-197) -- une forme volume sur l'espace des représentations du groupe $G_K$ du n\oe ud $K$ dans $SU(2)$. Plus exactement, si $\mathrm(Reg)(K)$ désigne l'ensemble des classes de conjugaison des représentations \emph(régulières) de $G_K$ dans $SU(2)$, alors $\mathrm(Reg)(K)$ est une variété unidimensionnelle et on établit qu'elle possède aussi une $1$-forme volume naturelle. On montre ensuite comment on peut interpréter cette forme volume en termes de torsion de Reidemeister non abélienne. On termine par des exemples : le calcul explicite de la forme volume que l'on vient de construire pour les n\oe uds toriques et les n\oe uds fibrés ainsi que celui de la torsion de Reidemeister des sphères d'homologie de Brieskorn à coefficients dans la représentation adjointe. On étudie également le comportement (à signe près) de la forme volume que l'on a construite sous l'effet d'une mutation.
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Strategic Determinants in the Software Industry : a study of six software companies in SwedenZink, Bjørn-Henrik January 2003 (has links)
<p>Background: The software industry is being described as an industry of fierce competition and rapid technology change. The innovation pace is said to be so high that today's new technology might be history tomorrow. Where do the companies of the software industry focus when making strategic decisions? According to the strategic literature, a firm can focus on either the external environment or the internal environment as strategic starting points. </p><p>Purpose: The purpose of this thesis is to find out what determines the strategy of firms in the software industry. </p><p>Procedure: Interviews with six software companies in Sweden. </p><p>Result: Four strategic determinants were identified: Flexible software solution, Markets that fit the software solution, Market Segmentation, Customers within the market segment. In this way, both the internal and external environment determines the strategies of the software companies.</p>
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The role of the Suppressor of Hairy-wing insulator protein in chromatin organization and expression of transposable elements in Drosophila melanogasterWallace, Heather Anne 01 December 2010 (has links)
ABSTRACT Chromatin insulators are required for proper temporal and spatial expression of genes in metazoans. Insulators are thought to play an important role in the regulation of gene expression through the formation of higher-order chromatin structures. One of the best characterized insulators is the Drosophila gypsy insulator, which is located in the gypsy retrovirus. Several proteins are required for gypsy insulator function, including Su(Hw), Mod(mdg4), and CP190. In addition to the gypsy insulator, these proteins are located throughout the genome at sites which are thought to correspond to endogenous insulators. Analysis of the distribution of insulator proteins across a region of chromosome 2R in Drosophila polytene chromosomes shows that Su(Hw) is found in three structures differentially associated with insulator proteins: bands, interbands and domains of coexpressed genes. Bands are formed by condensation of chromatin within genes containing one or more Su(Hw) binding sites, while Su(Hw) sites in interbands appear to form structures normally associated with open chromatin. Bands characterized by the lack of CP190 and BEAF-32 insulator proteins are formed by clusters of coexpressed genes, and these bands correlate with the distribution of specific chromatin marks. Conservation of the band interband pattern, as well as the distribution of insulator proteins in nurse cells, suggests that this organization may represent the basic organization of interphasic chromosomes. We also show that, in addition to the gypsy insulator, sequence analysis predicts the presence of Su(Hw) binding sites within a number of transposable elements. Su(Hw) binds to predicted sites within gtwin and jockey, which possesses enhancer-blocking activity. Su(Hw) affects the tissue-specific expression of transposable elements, although this effect is unrelated to the presence of Su(Hw) binding sites within the element or control of the elements via the piRNA pathway. Additionally, the effect of Su(Hw) on transposable element expression often differs from that of Mod(mdg4). Taken together, these results suggest that insulator proteins associate specifically with, and may help to define, various levels of chromatin organization on polytene chromosomes. Also, gypsy insulator proteins may influence the expression of transposable elements in a way that does not depend on Su(Hw) binding sites within the elements themselves.
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Strategic Determinants in the Software Industry : a study of six software companies in SwedenZink, Bjørn-Henrik January 2003 (has links)
Background: The software industry is being described as an industry of fierce competition and rapid technology change. The innovation pace is said to be so high that today's new technology might be history tomorrow. Where do the companies of the software industry focus when making strategic decisions? According to the strategic literature, a firm can focus on either the external environment or the internal environment as strategic starting points. Purpose: The purpose of this thesis is to find out what determines the strategy of firms in the software industry. Procedure: Interviews with six software companies in Sweden. Result: Four strategic determinants were identified: Flexible software solution, Markets that fit the software solution, Market Segmentation, Customers within the market segment. In this way, both the internal and external environment determines the strategies of the software companies.
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Aneuploidy compensatory mechanisms and genome-wide regulation of gene expression in Drosophila melanogasterLundberg, Lina January 2013 (has links)
Stimulation or repression of gene expression by genome-wide regulatory mechanisms is an important epigenetic regulatory function which can act to efficiently regulate larger regions or specific groups of genes, for example by compensating for loss or gain of chromosome copy numbers. In Drosophila melanogaster there are two known chromosome-wide regulatory systems; the MSL complex, which mediates dosage compensation of the single male X-chromosome and POF, which stimulates expression from the heterochromatic 4th chromosome. POF also interacts with the heterochromatin inducing protein HP1a, which represses expression from the 4th chromosome but which also has been assigned stimulatory functions. In addition to these two, there is another more elusive and less well-characterized genome-wide mechanism called buffering, which can act to balance transcriptional output of aneuploidy regions of the genome (i.e. copy number variation). In my thesis, I describe the presence of a novel physical link between dosage compensation and heterochromatin; mediate by two female-specific POF binding sites, proximal to roX1 and roX2 on the X chromosome (the two non-coding RNAs in the MSL complex). These sites can also provide clues to the mechanisms behind targeting of chromosome-specific proteins. Furthermore, to clarify the conflicting reports about the function of HP1a, I have suggested a mechanism in which HP1a has adopted its function to different genomic locations and gene types. Different binding mechanisms to the promoter vs. the exon of genes allows HP1a to adopt opposite functions; at the promoter, HP1a binding opens up the chromatin structure and stimulates gene expression, whereas the binding to exons condense the chromatin and thus, represses expression. This also causes long genes to be more bound and repressed by HP1a. Moreover, I show that buffering of monosomic regions is a weak but significant response to loss of chromosomal copy numbers, and that this is mediated via a general mechanism which mainly acts on differentially expressed genes, where the effect becomes stronger for long genes. I also show that POF is the factor which compensates for copy number loss of chromosome 4.
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