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Identification of Potential Adhesins Shared Among Isolates of Actinobacillus Species and Actinobacillus-Like Bacteria Cultured from Ram Lambs with Clinical EpididymitisLiu, Yu-Wen 01 May 1991 (has links)
Ram lamb epididymitis, a serious reproductive disease of sheep, is caused principally by bacteria belonging to the genera Haemophilus and Actinobacillus. Six bacteria were studied: the American Type Culture Collection (ATCC) of Actinobacillus seminis (ATCC 15768), ATCC of Actinobacillus actinomycetemcomitans (ATCC 29522), field isolates of A seminis (86722 and 4101) and field isolates of Actin obacillus- like bacteria (Y136 and D107). The objectives of this study were to quantitate the adhesion of these 6 bacteria to bovine kidney epithelial cells (BKECs) and ram epididymal epithelial cells (REECs), evaluate the effect of rabbit polyclonal antibody prepared against ATCC 15768 (PoAb 15768) on bacterial adherence to BKECs and REECs, and partially characterize the adhesins present on these bacteria.
In a bacterial adhesion assay (BAA), strain and species differences were noted. The number of bacteria adhering to each BKEC ranged (rom a low of 4.27 ± 1.00 (Actinobacillus-like 0107) to a high of 31.84 ± 2.00 (A seminis 86722). The number of bacteria adhering to each REEC ranged from a low of 3.05 ± 0.34 (Actinobacill us-like 0107) to a high of 21.61 ± 2.03 (Actinobacillus like Yl36). In a bacterial inhibition assay (BIA), PoAb 15768 inhibited the adhesion of ATCC 15768 to both BKECs and REECs by 5%. This same antiserum inhibited the adhesion of ATCC 29522 to BKECs by 14.5% and to REECs by 22%. The inhibition of A seminis 86722 adherence to BKECs and to REECs was less than 14% and 35%, respectively. For A seminis 4101, Actinobacillus-like Y136, and Actinobacillus-like 0107, PoAb 15768 failed to prevent adhesion to either BKECs or REECs. When the 6 bacteria were analyzed by autoradiography, 2 (Actinobacillus-like 0107) to 8 (ATCC 29522) potential adhesins were identified. However, the pathogenicity has not been firmly established for many Actinobacillus species and Actinobacillus-like bacteria. The potential adhesins identified in this study were not unequivocally confirmed as bacterial adhesins. An in vit ro model may facilitate the recognition of potential adhesins used by Actinobacillus species and Actinobacillus-like bacteria and may eventually lead to the development of an efficacious bacterin to prevent epididymitis in ram lambs at risk.
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A social and cultural history of the federal prohibition of psilocybinWark, Colin D. January 2007 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on December 17, 2007) Vita. Includes bibliographical references.
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Etude des phénomènes électrothermiques liés à l'amorphisation et à la cristallisation d'un matériau à changement de phase pour application aux mémoires non volatilesGIRAUD, Vincent 26 October 2005 (has links) (PDF)
Les mémoires PC-RAM intègrent entre deux électrodes un matériau à changement de phase, le chalcogénure Ge2Sb2Te5, qui peut basculer réversiblement entre un état amorphe résistif (OFF) et un état cristallin conducteur (ON). Le but de la thèse est d'étudier les phénomènes électrothermiques intervenant lors de l'amorphisation et la cristallisation. Nous caractérisons les différences thermiques et électriques des deux phases, notamment par la mesure de leur conductivité thermique (méthode 3 ω), et par le tracé des caractéristiques électriques I(V). Nous étudions également en détail les mécanismes de la transition OFF --> ON, pour laquelle nous mettons en évidence la formation d'un filament amorphe conducteur instable.Nous présentons les résultats des tests dynamiques effectués sur nos cellules microniques et submicroniques.Enfin, nous analysons quelques modélisations et simulations numériques, en montrant la difficulté expérimentale à éviter la fusion lors du processus de cristallisation.
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Implementation of a Zero Aware SRAM Cell for a Low Power RAM GeneratorÅkerman, Markus January 2005 (has links)
<p>In this work, an existing generator for layout of Static Random Access Memory (SRAM) is improved. The tool is completed with a block decoder, which was missing when the thesis started. A feature of generating schematic files is also added. The schematics are important to get a better overview, to test parts properly, and enable Layout versus Schematics (LVS) checks.</p><p>The main focus of this thesis work is to implement and evaluate a new SRAM cell, called Zero Aware Asymmetric SRAM cell. This cell saves major power when zeros are stored. Furthermore the pull-up circuit is modified to be less power consuming. Other parts are also modified to fit the new memory cell.</p><p>Several minor flaws are corrected in the layout generator. It does still not produce a complete memory without manual interventions, but it does at least create all parts with one command. Several tests, including Design Rule Checks (DRC) and LVS checks, are carried out both on minor and larger parts. Development of documentation that makes it easier for users and developers to use and understand the tool is initiated.</p>
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Spädbarnsanalys : När samspelet mor - barn inte fungerarHübner, Ulrika January 2010 (has links)
<p>The aim of the study is to investigate the practice of psychoanalysis with infants, and its effect on mother and child. With psychoanalytical thoeries and contemporary research on infants interaction as a basis, five interwievs with psychoanalysts in practice has been done. Also taking part of a clinical meeting with nine psychoanalysts has been done. Two of the interwieved analysts where part of this meeting, therefor the total sum of twelve psychoanalysts who reports their thoughts about the process i infantanalysis. The study also includes three participating observations of infantanalysis. The collected material has been examined with the intention to understand the psychoanalysts own experiences as well as the eventual effect the analys could have on mother, child and sometimes the father. The psychoanalysts describes how the treatment really helps both mother an child, and the proof for this is the mothers way to change her way to interact with the baby. The result shows the analysts themselves believes the interaction mother – child is improving with help from analysis. The discussion debate however the eventual effect on mother – child can be established, how the analysis is practised and if the psychoanalysts way to treat children is anything anyone could practise.</p><p> </p> / <p>Syftet med denna studie är att undersöka psykoanalys med spädbarn och dess inverkan på mor-barn samspelet. Med utgångspunkt i psykoanalytiska teorier och nutida forskning om spädbarnets medfödda samspelskompetenser har fem intervjuer med praktiserande psykoanalytiker utförts. Utöver dessa fem intervjuer har medverkande på ett kliniskt möte med nio närvarande psykoanalytiker gjorts. Två av de intervjuade ingår i gruppen psykoanalytiker på det kliniska mötet; totalt redogörs tolv psykoanalytikers uppfattningar om processerna i spädbarnsanalys. I undersökningen ingår också tre deltagande observationer av spädbarnsanalys. Det insamlade materialet har granskats med intentionen att förstå både psykoanalytikernas egna upplevelser av spädbarnsanalysen, och den eventuella effekt analysen har på mor, barn och i vissa fall även fadern. Spädbarnsanalytikerna beskriver att behandlingen hjälper både mor och barn och beviset för det är att moderns beteende och förmåga att uttrycka sig förändras så att samspelet mor-barn fungerar bättre. Resultatet visar att spädbarnsanalytikerna själva anser sig se att samspelet mellan mor och barn stärks av analys. Diskussionen tar upp hur den eventuella effekten på mor - barn i analys kan påvisas, hur analysen praktiseras och om psykoanalytikerns sätt att bemöta spädbarn kan användas av alla som möter mor - barn par där samspelet inte fungerar.</p><p> </p>
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C-RAM : en amerikansk akronym eller en svensk förmåga?Pekkari, Johan January 2009 (has links)
<p>Det här självständiga arbetet i militärteknik avhandlar huruvida Försvarsmakten, med i huvudsak redan befintlig materiel, genom en teknisk aktiv skyddslösning kan uppnå en förbättrad skyddsförmåga mot indirekt eld. Förmågan som söks är främst avsedd för, men inte begränsad till, att kunna nyttjas för att erhålla ett förbättrat skydd av Försvarsmaktens internationella camper. Därmed utgörs hotbilden framförallt av granatkastarammunition och raketer vilka inom ramen för en teknisk aktiv skyddslösning först måste kunna detekteras för att sen medge förvarning, eller ännu hellre avvärjning, innan de når sitt mål. Arbetets resultat presenteras i form av Förvarsmaktens möjligheter idag tillsammans med en rekommendation om hur skyddsförmågan kan säkerställas på något längre sikt.</p> / <p>This thesis in Military Technology deals with whether the Armed Forces, with mainly pre-existing equipment and using a technical active protection solution, can achieve enhanced protection capability against indirect fire. The capability sought is primarily for, but not limited to, the purpose of obtaining greater protection for the Swedish Armed Forces’ international camps. The threat, typically mortar ammunition and rockets, should within the framework of a technical active protection solution be detectable in order to provide early warning and preferably also interception before reaching its target. The results of the thesis are presented as possibilities for the Swedish Armed Forces today and as recommendations on how this capability can be achieved in the longer term.</p>
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Space-Efficient Data Structures in the Word-RAM and Bitprobe ModelsNicholson, Patrick 06 August 2013 (has links)
This thesis studies data structures in the word-RAM and bitprobe models, with an emphasis on space efficiency. In the word-RAM model of computation the space cost of a data structure is measured in terms of the number of w-bit words stored in memory, and the cost of answering a query is measured in terms of the number of read, write, and arithmetic operations that must be performed. In the bitprobe model, like the word-RAM model, the space cost is measured in terms of the number of bits stored in memory, but the query cost is measured solely in terms of the number of bit accesses, or probes, that are performed.
First, we examine the problem of succinctly representing a partially ordered set, or poset, in the word-RAM model with word size
Theta(lg n) bits. A succinct representation of a combinatorial object is one that occupies space matching the information theoretic lower bound to within lower order terms. We show how to represent a poset on n vertices using a data structure that occupies n^2/4 + o(n^2) bits, and can answer precedence (i.e., less-than) queries in
constant time. Since the transitive closure of a directed acyclic graph is a poset, this implies that we can support reachability
queries on an arbitrary directed graph in the same space bound. As far as we are aware, this is the first representation of an arbitrary directed graph that supports reachability queries in constant time,
and stores less than n choose 2 bits. We also consider several additional query operations.
Second, we examine the problem of supporting range queries on strings
of n characters (or, equivalently, arrays of
n elements) in the word-RAM model with word size Theta(lg n) bits. We focus on the specific problem of answering range majority queries: i.e., given a range, report the
character that is the majority among those in the range, if one exists. We show that these queries can be supported in constant time
using a linear space (in words) data structure. We generalize this
result in several directions, considering various frequency thresholds, geometric variants of the problem, and dynamism. These
results are in stark contrast to recent work on the similar range mode problem, in which the query operation asks for the mode (i.e., most frequent) character in a given range. The current best data structures for the range mode problem take soft-Oh(n^(1/2)) time per query for linear space data structures.
Third, we examine the deterministic membership (or dictionary) problem in the bitprobe model. This problem asks us to store a set of n elements drawn from a universe [1,u] such that membership queries
can be always answered in t bit probes. We present several new fully explicit results for this problem, in particular for the case
when n = 2, answering an open problem posed by Radhakrishnan, Shah, and Shannigrahi [ESA 2010]. We also present a general strategy for the membership problem that can be used to solve many related fundamental problems, such as rank, counting, and emptiness queries.
Finally, we conclude with a list of open problems and avenues for future work.
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Implementation of a Zero Aware SRAM Cell for a Low Power RAM GeneratorÅkerman, Markus January 2005 (has links)
In this work, an existing generator for layout of Static Random Access Memory (SRAM) is improved. The tool is completed with a block decoder, which was missing when the thesis started. A feature of generating schematic files is also added. The schematics are important to get a better overview, to test parts properly, and enable Layout versus Schematics (LVS) checks. The main focus of this thesis work is to implement and evaluate a new SRAM cell, called Zero Aware Asymmetric SRAM cell. This cell saves major power when zeros are stored. Furthermore the pull-up circuit is modified to be less power consuming. Other parts are also modified to fit the new memory cell. Several minor flaws are corrected in the layout generator. It does still not produce a complete memory without manual interventions, but it does at least create all parts with one command. Several tests, including Design Rule Checks (DRC) and LVS checks, are carried out both on minor and larger parts. Development of documentation that makes it easier for users and developers to use and understand the tool is initiated.
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Adaptive Range Counting and Other Frequency-Based Range Query ProblemsWilkinson, Bryan T. January 2012 (has links)
We consider variations of range searching in which, given a query range, our goal is to compute some function based on frequencies of points that lie in the range. The most basic such computation involves counting the number of points in a query range. Data structures that compute this function solve the well-studied range counting problem. We consider adaptive and approximate data structures for the 2-D orthogonal range counting problem under the w-bit word RAM model. The query time of an adaptive range counting data structure is sensitive to k, the number of points being counted. We give an adaptive data structure that requires O(n loglog n) space and O(loglog n + log_w k) query time. Non-adaptive data structures on the other hand require Ω(log_w n) query time (Pătraşcu, 2007). Our specific bounds are interesting for two reasons. First, when k=O(1), our bounds match the state of the art for the 2-D orthogonal range emptiness problem (Chan et al., 2011). Second, when k=Θ(n), our data structure is tight to the aforementioned Ω(log_w n) query time lower bound.
We also give approximate data structures for 2-D orthogonal range counting whose bounds match the state of the art for the 2-D orthogonal range emptiness problem. Our first data structure requires O(n loglog n) space and O(loglog n) query time. Our second data structure requires O(n) space and O(log^ε n) query time for any fixed constant ε>0. These data structures compute an approximation k' such that (1-δ)k≤k'≤(1+δ)k for any fixed constant δ>0.
The range selection query problem in an array involves finding the kth lowest element in a given subarray. Range selection in an array is very closely related to 3-sided 2-D orthogonal range counting. An extension of our technique for 3-sided 2-D range counting yields an efficient solution to adaptive range selection in an array. In particular, we present an adaptive data structure that requires O(n) space and O(log_w k) query time, exactly matching a recent lower bound (Jørgensen and Larsen, 2011).
We next consider a variety of frequency-based range query problems in arrays. We give efficient data structures for the range mode and least frequent element query problems and also exhibit the hardness of these problems by reducing Boolean matrix multiplication to the construction and use of a range mode or least frequent element data structure. We also give data structures for the range α-majority and α-minority query problems. An α-majority is an element whose frequency in a subarray is greater than an α fraction of the size of the subarray; any other element is an α-minority. Surprisingly, geometric insights prove to be useful even in the design of our 1-D range α-majority and α-minority data structures.
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A Rapid Assessment Method Examining the Ecological Health of Tidal Marine Wetlands in Galveston Bay, TexasStaszak, Lindsey Ann 2010 August 1900 (has links)
Wetlands are one of the most productive ecosystems in the world, housing diverse biota and serving important functions as nursery habitat and feeding grounds. However, nearly 70% of coastal wetlands, including 21% of the salt marshes in Texas, have been lost since 1950, due primarily to coastal development and declines in water quality. Restoration of wetlands is essential to reestablish lost functions, but there is no standard method to assess the ecological health of restored salt marshes in Texas. Numerous recent salt marsh restoration projects in Galveston Bay have made it an ideal model system to develop and implement an ecosystem health assessment, known as a rapid assessment method (RAM). In this study, I modified an established RAM, the Mid-Atlantic Tidal Fringe Assessment, to compare the ecological health of representative reference salt marshes to restored marshes around Galveston Bay.
I measured 14 biotic and abiotic characteristics at 12 restored and 6 reference sites around Galveston Bay, and then grouped those measurements into four functional groups: landscape/site characteristics, hydrology, wildlife habitat, and soil characteristics. I then developed a scoring system (minimum 0, maximum 100) to summarize the overall health of each site.
Most of the restored salt marshes in this study scored lower than reference marshes. The average reference site score was 81.8 and the average restored site score was 69.7. Functional group values for landscape/site characteristics, soil, and wildlife habitat were significantly lower in restored than in reference sites. In particular, restored sites had more hydrological modifications, more fill material, and fewer macrobenthos than reference wetlands.
The Galv-RAM effectively and efficiently identified restoration successes and weaknesses. With this information, management agencies can address restoration shortcomings by adapting management goals. The Galv-RAM will streamline monitoring protocols and facilitate long-term examination of restored wetland health. As a result, management decisions can be modified based on the scores received in different categories or variables to improve and or meet the goals of the project.
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