458 research outputs found
Mechanisms for Maintaining Cell Identity in C.elegans Olfactory Neurons
Maintenance of cell identity is a complex process that depends on developmentally determined transcriptional states and on environmental input. In neurons, which are both highly differentiated and highly sensitive to external stimuli, maintenance of identity is especially challenging. In this thesis, I describe the isolation and characterization of several genes involved in maintaining the identities of two olfactory neuron subtypes, AWCON and AWCOFF, in the nematode Caenorhabditis elegans. The AWCON and AWCOFF identities are specified by a stochastic decision during embryogenesis, but several of the genes involved in this embryonic decision are subsequently downregulated. Additional mechanisms must therefore act to maintain the AWCON and AWCOFF cell fates. I cloned and characterized a transcription factor, nsy-7, that was required to maintain expression of the AWCON marker str-2. nsy-7 mutants also misexpressed the AWCOFF marker srsx-3 in both AWCs. The chemotaxis phenotype of these mutants indicated that their defects in str-2 and srsx-3 expression corresponded to a more general change in cell identity from AWCON to AWCOFF. nsy-7 expression was restricted to AWCON by the signaling pathway that controls the initial fate decision. I collaborated with the Bulyk lab to discover a specific seven-nucleotide DNA sequence bound by the NSY-7 protein. This sequence was present in the srsx-3 promoter and required for NSY-7-mediated repression of srsx-3 in AWCON. Using this sequence, I was also able to predict new transcriptional targets of NSY-7. In a screen to identify additional genes affecting maintenance of str-2 and srsx-3 expression, I isolated nineteen mutants, including the uncharacterized conserved transcription factor hmbx-1 and components of the TGF! pathway. I showed that TGF! signaling is required continuously in adults to maintain srsx-3 expression and depends on dauer pheromone, an external sensory cue. I then identified new AWCON- and AWCOFF-specific markers and examined the extent to which changes in expression of str-2 or srsx-3 correlate with larger-scale changes in gene expression in the two AWC neurons. Together, my results indicate that several interlocking genetic pathways combine to maintain the AWCON and AWCOFF cell identities, including several factors not previously known to be involved in this process
Incorporating the Skeletal Remains of Two German Lutheran Cemeteries into the Surrounding Immigrant Population of Mequon, Wisconsin
The skeletal remains of 24 individuals were disinterred from the Altenburg Lutheran Church Society Cemetery and the German Evangelical Lutheran Cemetery (Stolz Site) in 1987 and 1989, respectively. Both unmarked cemeteries were located in Mequon, Wisconsin. The majority of these individuals were interred during the mid-nineteenth century, a time when German populations were becoming established as a major cultural and ethnic force within the region. Although these cemeteries have undergone multiple analyses, they have not been incorporated into larger discussions of settlement and mortuary practices in the area. By characterizing German immigrant settlement and mortuary practices, it is possible to incorporate the Altenburg and Stolz cemeteries into this larger framework
Water deficit induces changes in H⁺-ATPase activity and its gene expres sion in Zea mays L. roots
We investigated the functioning and the gene expression of H⁺-ATPase in the microsomal fraction enri ched
with plasmalemma vesicles isolated from roots of two Zea mays cultivars: Dostatok (drought resistant)
and Pereyaslivskiy (moderately tolerant to drought). Both cultivars grew during 21 days under the optimal
water supply (soil moisture — 70 %, control) and during 10 days under the water deficit conditions (soil
moisture — 30 %, experiment). An increase in the H⁺-ATPase hydrolytic activity in both cultivars under
the water stress has been detected under drought. The enzyme hydrolytic activity is increased by twice in
Dostatok and by1.3 times in Pereyaslivskiy. The H⁺-ATPase gene expression levels in both cultivars also
increased under water deficit. It is shown that, in roots of both maize cultivars, the increase of four isoforms
of H⁺-ATPase gene expression correlates with the increase of the hydrolytic enzyme activity under
water stress conditions. However, these parameters are more sustainable in the drought-resistant cultivar
Dosta tok, by allowing one value to use the hydrolytic activity of H⁺-ATPase as a biomarker of drought resistance
for corn varieties.Досліджено функціонування Н⁺-АТФази в мікросомальній фракції, збагаченій фрагментами плазмалеми (ПМ) з
коренів 21-добових рослин кукурудзи двох сортів: Достаток (посухостійкий) та Переяслівський (не посухостійкий), які зростали за умов достатнього водозабезпечення, при вологості субстрату 70 % та за умов водного
дефіциту, протягом 10 діб, при вологості субстрату 30 %, а також експресію генів цього ензиму. Виявлено підвищення гідролітичної активності H⁺-АТФази в ПМ з коренів кукурудзи за умов посухи вдвічі в сорту Достаток і
в 1,3 раза — в сорту Переяслівський. Встановлено, що рівень експресії генів у обох сортів за умов водного
дефіциту був вищим, ніж за умов достатнього водозабезпечення, що корелює з даними гідролітичної активності
ензиму, яка також була вищою в умовах дефіциту води. Причому ці показники мали більш сталий характер у
посухостійкого сорту Достаток, що дає підставу використовувати значення гідролітичної активності H⁺-
АТФази як біомаркер посухостійкості сортів кукурудзи.Проведены исследования функционирования H⁺-АТФазы в микросомальной фракции, обогащенной фрагментами
плазмалеммы (ПМ) из корней 21-суточных растений кукурузы двух сортов: Достаток (засухоустойчивый) и
Переясловский (не засухоустойчивый), которые росли в условиях достаточного водообеспечения, при влажности
субстрата 70 % и в условиях водного дефицита, на протяжении 10 суток, при влажности субстрата 30 %, а
также экспрессии генов этого энзима. Установлено повышение гидролитической активности H⁺-АТФазы в ПМ из
корней кукурузы в условиях засухи в два раза у сорта Достаток и в 1,3 раза у сорта Переясловский. Показано, что
уровень экспрессии генов у обоих сортов в условиях водного дефицита был более высоким, чем в условиях достаточного водообеспечения, что коррелирует с данными по определению гидролитической активности энзима,
которая также была более высокой в условиях дефицита воды. Причём эти показатели имели более устойчивый
характер у засухоустойчивого сорта Достаток, что позволяет использовать значения гидролитической активности H⁺-АТФазы в качестве биомаркера засухоустойчивости сортов кукурузы
DM-PhyClus: A Bayesian phylogenetic algorithm for infectious disease transmission cluster inference
Background. Conventional phylogenetic clustering approaches rely on arbitrary
cutpoints applied a posteriori to phylogenetic estimates. Although in practice,
Bayesian and bootstrap-based clustering tend to lead to similar estimates, they
often produce conflicting measures of confidence in clusters. The current study
proposes a new Bayesian phylogenetic clustering algorithm, which we refer to as
DM-PhyClus, that identifies sets of sequences resulting from quick transmission
chains, thus yielding easily-interpretable clusters, without using any ad hoc
distance or confidence requirement. Results. Simulations reveal that DM-PhyClus
can outperform conventional clustering methods, as well as the Gap procedure, a
pure distance-based algorithm, in terms of mean cluster recovery. We apply
DM-PhyClus to a sample of real HIV-1 sequences, producing a set of clusters
whose inference is in line with the conclusions of a previous thorough
analysis. Conclusions. DM-PhyClus, by eliminating the need for cutpoints and
producing sensible inference for cluster configurations, can facilitate
transmission cluster detection. Future efforts to reduce incidence of
infectious diseases, like HIV-1, will need reliable estimates of transmission
clusters. It follows that algorithms like DM-PhyClus could serve to better
inform public health strategies
The Equitable Inclusion of Women in Higher Education: Some Consequences for Teaching
Although admission of women to higher education has increased, equitable inclusion of women in the academy has not kept pace. Women often experience marginality in the classroom because they may have different styles of learning and because women’s experiences are not represented in mainstream knowledge. We suggest a narrative, inductive teaching strategy that deliberately acknowl- edges women’s differences and that will contribute to knowledge. This strategy requires teaching practices aimed at (1) establishing an affirming student/teacher relationship, (2) facilitating relationships among students, (3) enabling students to articulate their knowledge and experience, and (4) helping students to engage meaningfully with course content. This approach raises new difficulties for teach- ers, difficulties to be overcome in pursuing the equitable inclusion of women in higher education. Bien que de plus en plus de femmes poursuivent des études supérieures, l’inclu- sion équitable des femmes dans les corps professoraux laisse à désirer. La marginalité dont font l’expérience les femmes dans les salles de cours tient peut- être au fait qu’elles ont des styles d’apprentissage différents et que les expérien- ces des femmes ne sont pas représentées dans les connaissances courantes. Nous proposons une stratégie pédagogique narrative et inductive qui reconnaît délibéré- ment les différences des femmes et qui contribuera à l’évolution des connaissan- ces. Cette stratégie exige des méthodes d’enseignement qui visent (1) à établir une relation manifeste entre l’étudiant et le professeur, (2) à faciliter les relations entre les étudiants, (3) à permettre aux étudiants d’articuler leurs connaissances et leurs expériences et (4) à aider les étudiants à s’engager d’une manière féconde vis-à-vis de la matière du cours. Cette approche pose de nouvelles difficultés aux professeurs, difficultés qui seront surmontées par l’inclusion équitable des femmes dans l’enseignement supérieur.
Role of HIV Subtype Diversity in the Development of Resistance to Antiviral Drugs
Despite the fact that over 90% of HIV-1 infected people worldwide harbor non-subtype B variants of HIV-1, knowledge of resistance mutations in non-B HIV-1 and their clinical relevance is limited. Due to historical delays in access to antiretroviral therapy (ART) on a worldwide basis, the vast majority of reports on drug resistance deal with subtype B infections in developed countries. However, both enzymatic and virological data support the concept that naturally occurring polymorphisms among different nonB subtypes can affect HIV-1 susceptibility to antiretroviral drugs (ARVs), the magnitude of resistance conferred by major mutations, and the propensity to acquire some resistance mutations. Tools need to be optimized to assure accurate measurements of drug susceptibility of non-B subtypes. Furthermore, there is a need to recognize that each subtype may have a distinct resistance profile and that differences in resistance pathways may also impact on cross-resistance and the selection of second-line regimens. It will be essential to pay attention to newer drug combinations in well designed long-term longitudinal studies involving patients infected by viruses of different subtypes
An audiovisual works
RESUMÉ Název diplomové práce: Audiovizuální díla Ve své diplomové práci jsem se pokusil shrnout současnou právní úpravu audiovizuálních děl a práv a povinností s nimi spojených. V práci se hlavně orientuji na českou soukromoprávní právní úpravu, zejména zakotvenou v zákoně č. 121/2000 Sb., autorském zákoně, a s ohledem na licenční smlouvu v zákoně č. 89/2012 Sb., občanském zákoníku, či ostatních právních předpisech. V první kapitole se zaměřuji na různé prameny právní úpravy audiovizuálních děl a její historického vývoje v rámci mezinárodního práva veřejného, sekundárního práva EU a také národní úpravy. Ve druhé, třetí a čtvrté kapitole blíže rozvádím definici pojmu "audiovizuální dílo" a jeho autora a rovněž pak pojem a osobu autora "díla audiovizuálně užitého" a "výkonů audiovizuálně užitých". Tato díla a výkony společně se zvukovými záznamy představují základní prvky, z nichž mohou být audiovizuální díla utvářena. V kapitole páté a šesté zdůrazňuji zvláštní postavení výrobců zvukových a zvukově obrazových záznamů a definuji pojem "výrobce zvukového záznamu" a "výrobce zvukově obrazového záznamu". Kromě toho jsou výrobci zvukově obrazových záznamů navíc nadáni zvláštními právy ve vztahu k autorům děl a výkonů audiovizuálně užitých, a to za účelem nerušeného zhodnocení své investice. V sedmé a osmé...Name of the thesis: An audiovisual works In my final thesis, I tried to summarize the current legal regulation of an audiovisual works and the rights and obligation relating thereto. In the thesis, I mainly deal with Czech private law legislation, as regulated particularly in Act No. 121/2000 Coll., Copyright Act, as amended, and with regards to License Agreement in Act No. 89/2012 Coll., Civil Code, as amended, or other legal acts. In the first chapter, I focus on different sources of legal regulation of an audiovisual works and its historical development in public international law, secondary law of the EU and also in national legislation. In the second, third and fourth chapter, I elaborate on the defintion of the term "audiovisual work" and its author, as well as the term and author of a "work audiovisually used" and "performances audiovisually used." These works and performances, together with audio records, constitute basic elements which audiovisual works might be composed of. In chapter five and six, I highlight the specific position of audio and audiovisual records producers and define the term of a "producer of audio record" and "producer of audiovisual record". Moreover, producers of an audiovisual works are given particular rights towards authors of works and performances audiovisually...Institute of Copyright, Industrial Property and Competition LawÚstav práva autorského, práv průmyslových a práva soutěžníhoPrávnická fakultaFaculty of La
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