To see the other types of publications on this topic, follow the link: Two tails.
Dissertations / Theses on the topic 'Two tails'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 35 dissertations / theses for your research on the topic 'Two tails.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Wang, Zhao. "Synthesis of Polyhedral Oligomeric Silsesquioxane(POSS)-Based Shape Amphiphiles with Two Polymeric Tails of Symmetric or Asymmetric Compositions." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1366825911.
Full text
2
Cook, Clive George Carleton University Dissertation Engineering Electrical. "Two stage data echo cancellation utilizing orthonormal functions for echo tail cancellation." Ottawa, 1989.
Find full text
3
Otipoby, Kevin L. "CD22 regulates B cell fate via two signaling domains within its cytoplasmic tail /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/8335.
Full text
4
SHAH, RAVI. "A numerical study on backfilling of the tail void with two-component grout based on laboratory tests." Doctoral thesis, Politecnico di Torino, 2017. http://hdl.handle.net/11583/2680098.
Full textAbstract:
In mechanized tunneling the annular gap between the segmental lining and the surrounding soil caused by tunnel driving must be backfilled instantaneously with an adequate mortar. The annular gap is caused due to the conical shape, overcut and design of the shield. The soft ground tunneling has a prime focus on the settlement control and optimization of the parameters involved. The backfilling is a key component to reduce the surface settlements and deformations after the passage of the TBM. The main functions of backfilling are to 1. lock the segmental lining in position avoiding movements due to self-weight of the lining and other forces present; 2. To bear the loads transmitted by TBM backup weight; 3. Provide a uniform contact between the lining and surrounding soil and 4. Waterproofing the tunnel.
Recent developments in the field of backfilling have led to the development of a state-of-the-art two-component grouting system. A two-component grout consists of two components, Component A (Bentonite, water, cement and a retarder), component B (Sodium silicate based accelerator and water). When these two components are mixed just behind the annular gap, the grout starts to attain plasticity in a very quick time and thus, is able to transfer the load to the segmental lining in a very short time after its injection to the annular gap.
For a good backfilling grout it is important to satisfy certain engineering aspects (Fluidity, binding and gelling time, mechanical strength). The aim of this research is to understand the behavior of a two component grout in its fresh and hardened state and implement those obtained parameters in a numerical code. A series of laboratory tests are to perform on the two-component grout to determine its physical and mechanical behaviour. Bleeding, Marsh cone and gelling time tests are conducted on the fresh grout sample to test its chemical binding, viscosity and time taken to achieve plastic strain. A series of uniaxial compressive strength (UCS) tests are conducted on the grout sample to obtain its elastic modulus in its early days of setting (up to 28 days). In order to obtain and examine the state and strength of the grout in long term, a string of UCS tests are carried out on two-component grout samples cured at natural humidity of the soil in long terms (up to 1080 days). In addition to this, permeability and dewatering properties of a two-component are determined in its early state. Furthermore, the stiffness of the hardened grout sample in confined condition is determined by conducting oedometer tests. The oedeometer tests are conducted at various time intervals to obtain a complete time-dependent stiffness of the grout.
The research deals with the development of a robust numerical model taking into account all the relevant factors involved in mechanized tunnelling but focusing mainly on the backfilling procedure using FDM software FLAC 3D. The backfilling in the tail grout is modeled as normally applied pressure in a liquid state and later a time-dependent hardening behavior of the grout is initiated. The time-dependent behavior parameters are obtained from the laboratory tests conducted. A new constitutive model (CM) named as Plastic-Hardening (PH) is implemented to model the behavior of the surrounding soil. This CM gives the user a freedom to implement different stiffness for loading and unloading. Since the Mohr-Coulomb (MC) model specifies only one elastic modulus for both loading and unloading, it is unsuitable for cyclic and staged excavation procedures such as mechanized tunnelling itself. The PH CM is validated with the FEM software PLAXIS 3D before implementing it in FLAC 3D. Moreover, Hydro-mechanical coupled analysis is also conducted in the near-field domain of the grouting zones to update the permeability and stiffness of the grout due to consolidation.
5
Ardison, Kym Marcel Martins. "Nonparametric tail risk, macroeconomics and stock returns: predictability and risk premia." reponame:Repositório Institucional do FGV, 2015. http://hdl.handle.net/10438/13666.
Full textAbstract:
Submitted by Kym Marcel Martins Ardison (kymmarcel@gmail.com) on 2015-04-06T19:04:20Z
No. of bitstreams: 1
Tail Risk - Original.pdf: 817189 bytes, checksum: 02561a6a7cb94d1480a4f78933486df4 (MD5)<br>Approved for entry into archive by BRUNA BARROS (bruna.barros@fgv.br) on 2015-04-28T12:21:10Z (GMT) No. of bitstreams: 1
Tail Risk - Original.pdf: 817189 bytes, checksum: 02561a6a7cb94d1480a4f78933486df4 (MD5)<br>Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-05-04T12:33:49Z (GMT) No. of bitstreams: 1
Tail Risk - Original.pdf: 817189 bytes, checksum: 02561a6a7cb94d1480a4f78933486df4 (MD5)<br>Made available in DSpace on 2015-05-04T12:37:02Z (GMT). No. of bitstreams: 1
Tail Risk - Original.pdf: 817189 bytes, checksum: 02561a6a7cb94d1480a4f78933486df4 (MD5)
Previous issue date: 2015-02-12<br>This paper proposes a new novel to calculate tail risks incorporating risk-neutral information without dependence on options data. Proceeding via a non parametric approach we derive a stochastic discount factor that correctly price a chosen panel of stocks returns. With the assumption that states probabilities are homogeneous we back out the risk neutral distribution and calculate five primitive tail risk measures, all extracted from this risk neutral probability. The final measure is than set as the first principal component of the preliminary measures. Using six Fama-French size and book to market portfolios to calculate our tail risk, we find that it has significant predictive power when forecasting market returns one month ahead, aggregate U.S. consumption and GDP one quarter ahead and also macroeconomic activity indexes. Conditional Fama-Macbeth two-pass cross-sectional regressions reveal that our factor present a positive risk premium when controlling for traditional factors.
6
Lawson, Vannice Rose Marie. "The molecular cloning and developmental expression of two novel mRNAs encoding putative 14 kDa ODF and FS proteins of the rat sperm tail." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq28218.pdf.
Full text
7
Chen, Qian. "Bayesian Methods for Estimation, Inference and Forecasting of Flexible Models for Value-at-Risk and Tail Conditional Expectations." Thesis, The University of Sydney, 2011. http://hdl.handle.net/2123/7863.
Full textAbstract:
Forecasting financial risk and risk measurement methods have been of increasing interest for financial market regulators and financial institutions in the past two decades. While the parametric and semi-parametric models have been widely reviewed in the academic literature, the non-parametric methods are popular in practice among the financial institutions. This thesis examines the forecasting models for Value-at-Risk (VaR) and conditional Value-at-Risk for financial return series. The aims of this thesis are to: 1. Estimate and forecast the potential skewness and dynamics in higher moments for conditional return distributions; 2. Develop flexible parametric models that can accurately forecast the portfolio tail risk levels. 3. Examine the impacts of asymmetry in the volatility and that in the shape of the conditional return distributions on the risk level forecasting. 4. Derive an easily applicable backtesting method for conditional VaR or expected shortfall. 5. Improve the efficiency and accuracy of Bayesian computational schemes for parameter estimation and forecasts. To achieve the above goals, this thesis first proposes a parametric approach to estimating and forecasting Value-at-Risk (VaR) and Expected Shortfall (ES) for a heteroscedastic financial return series. A GJR-GARCH is used to model the volatility process, capturing the leverage effect. To account for potential skewness and heavy tails, the model assumes an asymmetric Laplace (AL) distribution as the conditional distribution of the financial return series. Furthermore, dynamics in higher moments are captured by allowing for a time-varying shape parameter in this distribution. An adaptive Markov chain Monte Carlo (MCMC) sampling scheme is used for estimation, employing the Metropolis--Hastings (MH) algorithm with a mixture of Gaussian proposal distributions. A simulation study shows accurate estimation and improved inference of parameters in comparison with a single Gaussian proposal MH method. We illustrate the model by applying it to forecast return series from four international stock market indices, as well as two exchange rates, and generating one step-ahead forecasts of VaR and ES. We apply standard and non-standard tests to these forecasts, as well as to those from some competing methods, and find that the proposed model performs favourably compared to many popular competitors; in particular, it is the only conservative model of risk among the models considered in this work over the period studied, which includes the recent financial crisis. However, an AL conditional ditribution may forecast risk too conservatively, and over-estimate the risk levels by a factor of two. In other words, the model implies the necessity for financial institutions to set aside up to twice as much regulatory capital as they need. With fixed total capital, the capital available to invest is reduced, leading to a lowered profit potential. To address this dilemma, this study develops and employs a two-sided Weibull (TW) distribution to capture potential skewness and fat-tailed behaviour in the conditional financial return distribution for the purposes of risk measurement and management, specifically focusing on the forecasting of VaR and conditional VaR measures. Four volatility model specifications, including both symmetric and nonlinear versions, are considered to capture heteroscedasticity. An adaptive Bayesian MCMC scheme is devised for estimation, inference, and forecasting. A range of conditional return distributions (TW, AL, symmetric, and skewed Student t) are combined with the four volatility specifications to forecast risk measures. The study finds that the GARCH-type volatility specification is much less important than that of the conditional distribution and, while the Student t distribution performs particularly well on VaR forecasting, the two-sided Weibull performs at least equally well for VaR, but the most favourably for conditional VaR forecasting, both prior to as well as during and after the recent financial crisis. Nonetheless, the TW distribution can be bimodal, while the conditional distribution of real financial return series are known to be uni-modal. To address this issue, this study develops a partitioned distribution, combining the Weibull tails with a uni-modal AL centre. The proposed distribution is combined with the GJR-GARCH volatility model, to estimate and forecast the VaR and Conditional VaR. The estimation is via an adaptive MCMC sampling scheme and the MH algorithm, with a more general and flexible mixture of Student t proposal distributions. A simulation study demonstrates the estimation is marginally closer to the true values than the mixture of Gaussian proposal distributions. The model is illustrated via application to real financial return series, generating one-day-ahead forecasts and is compared with several competing models. The forecasts are evaluated by formal and non-formal backtesting methods. The model-fitting performances are demonstrated by a range of residual tests. We find the partitioned distribution forecasts financial tail risks slightly less accurately than the TW, but is most favoured by the residual tests.
8
Johansson, Maya. "Vilka möjligheter ges barn med funktionsnedsättning att komma till tals? : – ur LSS-handläggares perspektiv." Thesis, Växjö University, School of Health Sciences and Social Work, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-5958.
Full textAbstract:
<p>About 29 000 different services was given by the Swedish welfare state to children with disabilities within the ages 0-22 years before October first in the year 2008. Studies about children with disabilities and their experiences of their situation have rarely been done and it is therefore difficult to know how they think and feel about their lives. Both Swedish law and the UN:s convention about children’s rights states that children have the right to tell their opinion in matters that are of their concern. Thus, we don´t know much about if and how the Swedish welfare state maintain this right towards children with disabilities. This is aimed to reveal if and how the Swedish welfare state, trough it´s municipality servants, give children with disabilities an opportunity to speak their mind trough the perspective of the municipality servant. This study is even aimed to reveal which difficulties, if any, the servants experience in their investigations of children with disabilities. The empirical material was analyzed trough a <em>perspective of children as actors and trough the theoretical ideas; <em>power-of-modeling and <em>the organizations many hands. A qualitative method was chosen to collect the empirical data for this study because this method is the best method in order to get the deep information that was needed in order to achieve a deeper understanding for the problem. The result is that children with disabilities don´t get the opportunity to speak their mind in their own cases because of many aspects such as; communication problems, the limitations within the law called LSS, the organizations limitations of the servants and the children’s own parents. </em></em></em></p>
9
Olovsson, Katja. "Samtal med barnhandläggare : Om barn i familjehem och deras rätt att komma till tals." Thesis, Stockholms universitet, Institutionen för socialt arbete - Socialhögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-104777.
Full textAbstract:
The purpose of this study was to examine how some child welfare case workers say they go about to give children in foster homes the opportunity to be heard. The idea was also to examine how much weight is given to the children’s views and if the respondents believe that the childrens right to be heard has improved over the time they have been working with foster children and if so, how? The study was conducted by using qualitative research method and the analysis of the results was made using Shier’s model of childrens participation. The results have also been tied to previous research in the area. The conclusions of this study was that according to the respondents it’s important that they get to know the children well so that the children can have confidence enough to speak their minds. They feel it is important that the children are listened to and the childrens views also have some influence in decision-making. The respondents also believe that the opportunities for the children to express their opinions have strengthened in recent years.
10
Saia, Rafael. "Proposta de classificação para a tipologia de produção Engineer to Order e definição das melhores práticas de manufatura em tais ambientes." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18156/tde-03122013-101535/.
Full textAbstract:
A capacidade de customização de produtos é considerada atualmente um fator de competitividade muito importante para a sobrevivência das empresas. A interferência dos clientes na concepção e na fabricação dos produtos está cada vez mais intensa. Dentre as várias estratégias de customização, a tipologia de produção Engineer to Order (ETO), na qual o cliente é envolvido nas fases de design e desenvolvimento do produto, é considerada a mais complexa e ineficiente. Embora o número de organizações classificadas como ETO seja bastante elevado e os problemas associados a esta tipologia sejam bem conhecidos, não existem registros consolidados na literatura sobre qual é a melhor abordagem de gestão das cadeias produtivas destes ambientes. Além disso, as práticas de gestão sugeridas por alguns pesquisadores consideram a tipologia ETO um sistema homogêneo, no qual todas as empresas recebem as mesmas abordagens. No entanto, dentro do universo ETO existem empresas com diferentes tipos de customização. Algumas empresas fabricam produtos completamente novos, desenvolvidos para clientes específicos. Outras empresas fornecem produtos com estrutura híbrida, na qual alguns componentes são padronizados e outros são customizados. A grande diferença entre os sistemas produtivos ETO exige que cada ambiente receba uma abordagem específica para o seu modelo de negócio. Com o intuito de preencher esta lacuna, o presente trabalho propõe uma classificação da tipologia ETO com recomendações das melhores práticas de manufatura para cada subtipologia ETO definida. A classificação proposta foi baseada em estudos de caso com implementações de projetos de melhoria em diferentes ambientes ETO.<br>The ability of customizing products is considered a very important competitive factor for the survival of nowadays companies. The power of customers influence on products conception and manufacturing is increasing. Among the various customization strategies, the Engineer to Order (ETO) production typology, in which customers are involved at product design and development stages, is considered the most complex and inefficient. Although there are many organizations classified as ETO and the problems associated with this typology are very known, there is a lack of agreement in literature about the best practices for the value chain management of these environments. Furthermore, the practices suggested by some researchers consider the ETO typology as a homogeneous system where all the companies receive the same approach. However, the companies of the ETO universe show different customization approaches. Some companies produce products completely new and designed for specific customers. Other companies provide products with a hybrid structure which is formed by standardized and customized components. The big difference found between all kinds of ETO production systems implies that specific approaches have to be applied for each business model. In order to fill this gap, this work offers a classification for the ETO typology with some recommendations of the best manufacturing practices for each ETO sub typology defined. The proposed classification was based on cases of improvement projects implemented in different ETO environments.
11
Humbert, Xavier. "Détection et pronostic de l'effet blouse blanche en médecine générale Office white-coat effect tail and long-term cardiovascular risks in the Gubbio residential cohort study Impact of Sex on Office White Coat Effect Tail: Investigating Two Italian Residential Cohorts Office white-coat effect tail: a useful tool in family practice? White-coat hypertension: management and adherence to guidelines by European and Canadian GPs : a cross-sectional clinical vignette study." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMC403.
Full textAbstract:
L’effet blouse blanche (EBB) est un phénomène connu depuis de nombreuses années. Son diagnostic est rendu difficile par les mesures multiples de pression artérielle à réaliser (en consultation et en ambulatoire). De plus, son influence cardio-vasculaire est mal connue. Dans ce contexte, nous avons développé un concept d’effet blouse blanche résiduel (EBBR), permettant de diminuer le nombre de mesures de pression artérielle à réaliser (en consultation seulement). Il est bien corrélé à l’EBB et moins à l’hypertension blouse blanche. Son impact cardio-vasculaire est important notamment chez la femme, faisant de l’EBBR, un facteur de risque cardio-vasculaire à part entière. Les recommandations doivent mieux appréhender l’EBB afin d’améliorer sa prise en charge en soins courants<br>The white coat effect (WCE) has been known for many years. Its diagnosis is made difficult by the multiple blood pressure measurements to be carried out (in clinic and outpatient). In addition, its cardiovascular influence is poorly understood. In this context, we have developed a concept of office white coat effect tail (OWCET), making it possible to reduce the number of blood pressure measurements to be carried out (in clinic only). It is well correlated with the WCE and less with white coat hypertension. Its cardiovascular impact is significant, especially in women, making EBBR a full-blown cardiovascular risk factor. The recommendations should better understand the WCE to improve its management in clinical practice
12
Nauen, Jennifer Claire. "Biomechanics of two aquatic defense systems : 1. The scaling of tail-flip kinematics and force production by the California spiny lobster Panulirus interruptus : 2. Shear sensitivity and interspecific variation in flow-stimulated dinoflagellate bioluminescence /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9823710.
Full text
13
NDRECA, SOKOL. "Queueing models for air traffic." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/1113.
Full textAbstract:
In this thesis we study
some queueing models that are worthwhile to
understand the air-traffic congestion.
From the point of view of classical queueing theory the air traffic
system is difficult to study, mainly because it is hard even to define
the basic quantities of the theory.
The system becomes complex, since there are a many factor, that
influence the air-traffic like weather conditions, technical problems,
air turbulences caused by the different types of aircrafts.
Thus is necessary to investigate the
impact of the arrivals of aircraft on air traffic.
A common hypothesis in literature is to assume that the arrivals of
aircrafts are very well modeled by a Poisson process. This assumption
is suitable for mathematical modelling,
due to the memoryless property of Poisson process that simplifies
the study of congestion in such systems.
Our first goal is to study the
property of a model of the arrival process to a system
and to compare its features to the Poisson process.
We will show in this work why
the Poissonian hypothesis for air-traffic is doomed to failure
even if the Poisson process is very similar to our process
if it is observed on a time scale sufficiently short.
We found interesting connections of this model with the statistical
mechanics of Fermi particles.
Once one understands the properties of arrival process to the system,
to study its evolution we use the theory of Markov chain.
Our second goal is
the study of the stochastic properties of other queueing systems,
relevant in the applications,
where the arrivals are described according general independent
stochastic process and the service is delivered according to various
disciplines. This
corresponds to the study of the stationary measure of a Markov chain.
In order to find the stationary distribution of such Markov chain we use
the generating function technique.
Part of this thesis is a discussion of the criteria usually presented
in literature to evaluate the goodness of various approximation
schemes. It will turn out, actually, that the generating function is
not always possible to compute explicitly, and some numerical
procedures are necessary in order to compute the relevant quantities
of the system.<br>In questa tesi studiamo dei modelli di coda che sono utili per capire
la congestione del traffico aereo. Dal punto di vista della teoria delle
code classica e' difficile studiare il sistema del traffico aereo, soprattutto
perche' e' complesso definire le quantita' di base della teoria.
Il sistema diventa complesso, poiche' ci sono molti fattori che influiscano sul traffico aereo, ad esempio le condizioni meteo, problemi tecnici, le turbolenze dell'aria causate da diversi tipi di aeromobili.
Quindi per capire il traffico aereo diventa necessario studiare la distribuzione degli arrivi degli aeroplani.
In letteratura l'ipotesi comune e' di assumere che gli arrivi degli aeroplani sono descritti molto bene dal processo di Poisson. Questa assunzione e' adatto per i modelli matematici, per la proprieta' di assenza di memoria del processo di Poisson che semplifica lo studio della congestione in tale sistema. Il primo obiettivo di questa tesi e' di studiare le proprieta' di un processo degli arrivi degli aeromobili
al sistema e di confrontare tale processo con il processo di Poisson.
In questo lavoro mostriamo come l'ipotesi Poissoniana per il traffico aereo
e' destinato a fallire anche se il processo Poissoniano e' molto simile al nostro modello degli arrivi se viene osservato su una scala di tempo opportunamente corta.
Troviamo poi, nella trattazione del nostro processo, una connessione interessante del nostro modello con la meccanica statistica di Fermioni.
Una volta comprese le proprieta' del processo degli arrivi al sistema, per studiare la sua evoluzione usiamo la teoria Markoviana. Il secondo obiettivo di questa tesi e' lo studio delle proprieta' stocastiche
di altri sistemi di coda, sempre rilevanti nelle applicazioni, in cui gli arrivi sono generali ma indipendenti, e discipline di servizio particolari rendono non banale
lo studio della distribuzione stazionaria della catena. Questo corrisponde a studiare la misura stazionaria di certe catene di Markov. Per trovare la distribuzione stazionaria usiamo il metodo della funzione generatrice. Una parte di questa tesi e' la discussione dei criteri, di solito presentati in letteratura, per valutare l'ottimalita' dei vari schemi di approssimazione.
14
Yang, Kefei [Verfasser], Sigrid [Akademischer Betreuer] Hoyer-Fender, Wolfgang [Akademischer Betreuer] Engel та ін. "Functional Analysis of Two Major Sperm Tail Proteins Identifies ODF1 as Being Essential for the Tight Linkage of the Sperm Head to the Tail via SPAG4 and ODF2 as A Component of the β-catenin Destruction Complex / Kefei Yang. Gutachter: Sigrid Hoyer-Fender ; Wolfgang Engel ; Michael Kessel ; Ernst A. Wimmer ; Detlef Doenecke ; Martin Göpfert. Betreuer: Sigrid Hoyer-Fender". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1069235199/34.
Full text
15
Nuzum, Sean Robert. "Aircraft Thermal Management using Liquefied Natural Gas." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1462460693.
Full text
16
Guo, Xiangxue. "Biochemical and Bioinformatics Analysis of CVAB C-Terminal Domain." Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/biology_diss/3.
Full textAbstract:
Cytoplasmic membrane proteins CvaB and CvaA and the outer membrane protein TolC form the bacteriocin colicin V (ColV) secretion system in Escherichia coli. CvaB functions as an ATP-binding cassette transporter with nucleotide-binding motifs in the C-terminal domain (CTD). To study the role of CvaB-CTD in the ColV secretion, a truncated construct of this domain was made and over-expressed. Different forms of CvaB-CTD were obtained during purification, and were identified as monomer, dimer, and oligomer on gel filtration. Nucleotide binding was shown critical for the CvaB-CTD dimerization: oligomers could be converted into dimers by nucleotide bindings; the removal of nucleotide from dimers resulted in transient monomers followed by CTD oligomerization and aggregation; no dimer form could be cross-linked from the nucleotide-binding deficient mutant D654H. The spatial proximity of the Walker A site and ABC signature motif in CTD dimer was identified through disulfide cross-linking of mixed CvaB-CTD with mutants A530C and L630C, while mutations did not dimerize individually. Those results indicated that the CvaB-CTD formed a nucleotide-dependent head-to-tail dimer. Molecular basis of differential nucleotide bindings was also studied through bioinformatics prediction and biochemical verification. Through sequence alignment and homology modeling with bound ATP or GTP, it was found that the Ser503 and Gln504 on aromatic stacking region (Y501DSQ-loop) of CvaB-CTD provided two additional hydrogen-bonds to GTP, but not to ATP. Site-directed mutations of the S503A and/or Q504L were designed based on the model. While site-directed mutagenesis studies of Walker A&B sites or the ABC signature motif affected little on the GTP-binding preference, the double mutation (S503A/Q504L) on the Y501DSQ-loop increased both ATP-binding and ATPase activity at low temperatures. The double mutant showed slight decrease of GTP-binding and about 10-fold increase of the ATP/GTP-binding ratio. Similar temperature sensitivity in nucleotide-binding and activity assays were identified in the double mutant at the same time. Mutations on the Y501DSQ-loop did not affect the ColV secretion level in vivo. Together, the Y501DSQ-loop is structurally involved in the differential binding of GTP over ATP.
17
Corrêa, Fernando. "Estudos termodinâmicos e estruturais da interação cabeça-cauda da , alpha-tropomiosina muscular." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-22072008-112345/.
Full textAbstract:
Tropomiosina (Tm) é uma das proteínas que compõe o filamento fino (actina, Tm, Troponina) do sistema muscular esquelético e desempenha um importante papel na regulação da contração muscular. Tm é um coiled-coil de 284 resíduos que forma longos homopolímeros lineares através da sobreposição de onze resíduos entre os terminais de Tms adjacentes (Interação cabeça-cauda) em condições de baixa força iônica. A presença de vários resíduos carregados (D2, K5, K6, K7, D275, H276 e D280) nas extremidades da Tm sugere que contatos intermoleculares eletrostáticos entre estes aminoácidos podem ter um importante papel na estabilidade dos polímeros. Entretanto, a estrutura do complexo cabeça-cauda demonstra que a maioria dos contatos intermoleculares na interface é de natureza hidrofóbica. A fim de analisarmos a contribuição dos grupos carregados para a estabilidade do complexo cabeça-cauda, construímos fragmentos recombinantes correspondentes à metade amino (ASTm1-142 ) e carboxi (Tm143-284(5OHW269)) terminais da proteína contendo mutações pontuais daqueles resíduos para alanina, e adicionalmente H276 para Glu. Medimos a afinidade entre todas as possíveis combinações destes fragmentos na ausência e presença de íons Mg2+, visto que este cátion está sempre presente em condições fisiológicas e é importante para estabilizar a interação entre Tm e actina. Os efeitos das mutações foram analisados por simulações de docking, desnaturações térmicas e ciclos de duplos mutantes. Os resultados demonstram que os aminoácidos K5, K7 e D280 presentes na interface formam contatos intermoleculares essenciais para a estabilidade do complexo. Enquanto, D2, K6, D275 e H276 não participam na formação de contatos intermoleculares, no entanto, contribuem para a estabilidade da interação cabeça- cauda através de suas interações intramoleculares que atuam na estabilidade das hélices individuais. Os aumentos na estabilidade da metade C-terminal da Tm (Tm143-284(5OHW)) induzidos por Mg2+ foram dependentes das mutações neste trecho da proteína sugerindo a presença de um sítio de ligação para este íon na extremidade carboxi terminal da molécula no trecho que forma a interação cabeça- cauda. Construímos um fragmento menor do C-terminal (Tm259-284(W269)) para acompanharmos mudanças no deslocamento químico induzidas pela ligação do íon usando ressonância magnética nuclear. Os resultados obtidos comprovaram nossa hipótese e nos permitiram definir pela primeira vez que a estrutura da Tm tem um ou mais sítios de ligação Mg2+ em uma região próxima ao resíduo H276 que está localizado entre vários resíduos carregados negativamente que participam da interação cabeça-cauda. Por último, estudamos os efeitos de solventes cosmótropicos (TFE e glicerol) nas estabilidades dos fragmentos da Tm, uma vez que a instabilidade (flexibilidade) da extremidade C-terminal é importante para a formação do complexo cabeça-cauda. Observamos que TFE, porém não glicerol, reduziu a afinidade entre os terminais. Ambos os co-solventes induziram aumentos na estabilidade dos fragmentos, no entanto, apenas TFE induziu um aumento no conteúdo de α-hélice e causou uma redução significativa na cooperatividade de desenovelamento das proteínas. Estes resultados indicam que estes compostos orgânicos estabilizam as estruturas dos fragmentos individuais da Tm de maneiras diferentes e que estas diferenças podem estar relacionadas aos diferentes efeitos observados na formação da interação cabeça-cauda.<br>Tropomyosin (Tm) is a protein component of the skeletal muscle thin filament (actin, Tm, Troponin) which has an important role in the regulation of muscle contraction. Tm is a dimeric coiled-coil (284 aminoacids) which forms long linear homopolymers through the overlap of eleven residues of adjacent Tm termini (Head- to-tail interaction) in low ionic strength conditions. The presence of several charged amino acids (D2, K5, K6, K7, D275, H276 e D280) in Tm extremities suggests that electrostatic contacts among those residues may have an important role in the stability of the polymers. Nevertheless, the solution structure of the head-to-tail complex demonstrated that most of the contacts in the interface are hydrophobic. In order to study the contribution of these charged residues to the stability of the head- to-tail complex, we built recombinant fragments corresponding to the amino (ASTm1-142) and carboxy (Tm143-284(5OHW269)) termini containing single mutations of those amino acids to alanine, and additionally a substitution of H276 for Glu. We measured the binding affinities among all possible combinations of wild-type and mutant fragments in the absence or presence of Mg2+ ions. This cation is always physiologically present in the muscle and it is known to strengthen the binding of Tm to actin. The effects of the mutations were analyzed by protein-protein docking, thermodynamic cycles and thermal denaturations. The results show that residues K5, K7 and D280 are essential to the stability of the complex. Though D2, K6, D275 and H276 are exposed to the solvent and do not participate in intermolecular contacts in the NMR structure, they may contribute to the complex stability by modulating the stability of the helices at the Tm termini. Mg2+-induced increases in stability of the C- terminal were sensitive to mutations in residues located in the head-to-tail overlap region, suggesting that Mg2+ ions may bind specifically to the carboxy extremity of the protein. We produced a small peptide (Tm259-284(W269)) to follow amide chemical shift perturbations upon Mg2+ binding by nuclear magnetic resonance measurements. The results obtained with this peptide allowed us to define for the first time that the Tm structure has one or more Mg2+ binding sites in a region centered in the vicinity of H276 in which are located several negatively charged residues that participate in the head-to-tail interaction. We also studied the effects of kosmotropic co-solvents (TFE and glycerol) in the stability of Tm fragments, as the instability (flexibility) of the C- terminal region has been pointed as important for the formation of the head-to-tail complex. We observed that TFE, but not glycerol, reduces the affinity between the termini. Both TFE and glycerol increased the stability of the isolated N- and C- terminal fragments; however, only TFE caused an increase in the helical content and a significant reduction in the cooperativity of unfolding of the proteins. Our results show that these two co-solvents stabilize the structures of individual Tm fragments in different manners and that these differences may be related to their different effects on head-to-tail complex formation.
18
Vilander, Carolin, and Evelina Johansson. "Barnets vilja i tvister om vårdnad, boende och umgänge : En studie om hur barnets vilja framkommer och beaktas i svenska tingsrättsdomar." Thesis, Linnéuniversitetet, Institutionen för socialt arbete (SA), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-64939.
Full textAbstract:
The aim of this study was to increase understanding of the extent to which the child's will is given in Swedish courts' overall assessments of the best interests of the child in disputes on custody, resident and visitation (VBU). 18 District Court judgments have been collected from the database Zeteo via court judgments from Sweden's six Courts of Appeal. Based on a qualitative research effort, a content analysis was conducted on the judgments. The content analysis resulted in the following three categories being identified: The court judges according to the expressed will of the child, The court judges against the expressed will of the child, and The will of the child was omitted in the district court's assessment. The results were mainly analyzed based on childhood sociological perspectives, Hart’s ladder of participation and family law regulations. The theoretical framework was used to illustrate how the child was presented and socially constructed, and what impact this had on the space the child's will was given in the court's assessments of the best interests of the child. This was then reflected in the prevailing laws. The results of the study showed that the child's will appeared in about half of the cases, and that the court judged according to the will of the child in less than one third of them. The study also showed that the court tended to question the authenticity of the will of the children whose wishes did not comply with what the court considered to be the best interests of the child. In the majority of the cases where the children’s will were not given any room in the judgment, the court generally gave no reasons why the will was not reported.
19
Butterworth, Mary Michele. "Felinus Domus: A Veterinary Hospital for Cats in Old Town Alexandria, Virginia." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/34535.
Full textAbstract:
Throughout time man has discovered that the human form, in all its harmonious proportion, can be used as a guide, gauge and tool to design and build structures. However, the human figure has not been the only organic form used to create architecture. Many animals create dwellings that synchronize with not only their own unique physical characteristics and survival instincts, but with their aesthetic preferences as well. It is logical that a design should respond to its surroundings, program and most importantly, its inhabitants.
This thesis design is for two specific occupants: the cat and the human. They are both meant to inhabit the building wholly and simultaneously. The way each of them experiences and uses the space, however, differs greatly.
For a building to survive it needs many of the same things as living creatures: sunlight, air and movement, to name a few. It also needs to function like a living creature. It must breathe, sleep, respond to the changing seasons, and adapt over time. This thesis is an investigation of how both human and cat can dwell in a building of harmonious proportion, scale, light, and material.<br>Master of Architecture
20
Troilo, Maurizio. "Web 2.0, contenuti aperti e produzione tra pari: analisi economica delle possibili sinergie." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amslaurea.unibo.it/1201/.
Full textAbstract:
Analisi in chiave economica e sociale dell'evoluzione di Internet, delle tecnologie legate al Web 2.0, dei fenomeni della pirateria, del software libero ed open source, del copyleft, dei contenuti aperti e della produzione tra pari.
Introduzione dei concetti di economia del gratis ("freeconomics") e di coda lunga.
Consigli manageriali pratici per i nuovi mercati digitali e per la competizione nella rete Internet.
21
Son, Sébastien. "Organogels et aérogels obtenus à partir de phénylalanine : étude de l'organisation supramoléculaire et élaboration d'un nouveau type de super-isolant thermique." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0004/document.
Full textAbstract:
Depuis 1973, l’un des objectifs principaux de la France est la diminution de la consommation des énergies de chauffage des bâtiments du résidentiel et du tertiaire qui représentent plus de 40% de la consommation énergétique totale du pays. Le développement des isolants thermiques a été par conséquent un sujet de recherche qui a abouti à de nouveaux matériaux : les super-isolants thermiques de conductivité thermique inférieure à 25 mW.m-1.K-1. Les aérogels organiques de faible densité de Z-Phe-NH-Napht étudiés au LCPM présentent une structure fibrillaire qui leur confère des propriétés thermiques intéressantes malgré une résistance mécanique faible. Une étude fondamentale de l’organisation supramoléculaire nous a permis d’une part de démontrer l’existence de deux modes d’empilement des molécules organogélatrices : tête-à-tête (monocristaux) et tête-à-queue (gels), caractérisées par une signature infrarouge propre à des pseudo-cycles respectivement en C12 et C10/C14. D’autre part, nous avons étudié le mécanisme de formation séquentiel de ces gels et abouti à un modèle complet d’organisation de la molécule isolée à la fibre basé sur une symétrie hexagonale. En vue d’une commercialisation d’un isolant à base d’aérogel organique, nous avons tout d’abord optimisé le protocole d’obtention des aérogels pour ensuite travailler à l’amélioration des propriétés thermiques et mécaniques. Nous sommes parvenus à un nouvel isolant hydrophobe présentant une conductivité thermique de l’ordre de celles des super-isolants et de bonnes propriétés mécaniques compatibles avec les pré-requis industriels pour une application dans le bâtiment<br>Since 1973, France's main objective in this domain has been to reduce the consumption of energy in heating residential and industrial buildings, which represents more than 40% of the national consumption. Consequently, the development of heat insulators has been the subject of research which has resulted in new materials: super thermal insulators with a thermal conductivity of less than 25 mW.m-1.K-1. Organic aerogels with a low density of Z-Phe-NH-Napht have been studied at LCPM for the past 10 years. Despite their very weak mechanical resistance they present a fibrillar structure which gives them very interesting thermal properties. A fundamental study of the supermolecular self-assembly allowed us to demonstrate the existence of two stacking methods of gelling molecules: head-to-head (monocrystals) and head-to-tail (gels) which are characterized by a specific infrared signature to the pseudo-cycles respectively on C12 and C10/C14. In addition, we also studied the sequential formation mechanism of these gels which resulted in a full model of their molecular organization from the single molecule to the fiber and based on a hexagonal packing symmetry. In aim of commercializing an insulator made from organic aerogels, we firstly optimized the protocol for obtaining aerogels to then work on improving their thermal and mechanical properties. We created a new hydrophobic insulator which has both a thermal conductivity in the range of the super heat insulators' and good mechanical properties that are compatible with industrial prerequisites for the construction of buildings
22
Enee, Véronique. "Synthèse d'oligo(3-octylthiophènes) régioréguliers : briques moléculaires pour l'élaboration de polymères conjugués incluant des complexes de métaux de transition." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10012.
Full textAbstract:
Le but de ce travail consiste en la synthese d'un polymere conjugue a complexes organometalliques, afin de creer un materiau original jouissant des proprietes du polymere et du complexe organometallique. Ainsi, selon la longueur des bras espaceurs conjugues de la matrice polymere, un couplage entre sites metalliques voisins pourra se produire ou non. De plus, (et cela constitue notre objectif majeur), les proprietes intrinseques du polymere pourraient se coupler a celles du complexe: il serait alors possible de modifier les proprietes du polymere, en agissant sur celles du metal (ou inversement). Pour ce faire, le complexe organometallique doit etre integre dans la chaine conjuguee du polymere, tout en conservant la conjugaison. Il nous a fallu alors choisir l'espaceur conjugue (nature et longueur), le ligand et la position de couplage entre les deux entites precedentes adequats. Nous avons choisi, comme bras espaceurs conjugues, des oligo(3-octylthiophenes) qui possedent des proprietes de solubilite et de conductivite. Nous avons mis au point une nouvelle synthese par etapes, regiospecifique d'oligo(3-octylthiophenes) regioreguliers (aux couplages exclusivement tete a queue). L'originalite de notre methode reside dans la haute purete isomerique des oligomeres obtenus et dans les bons rendements. Nous avons choisi un ligand conjugue type bipyridine, connue pour sa capacite a complexer divers metaux. Nous avons optimise les conditions operatoires pour conduire, efficacement, le couplage entre l'unite complexante (bipyridine dihalogenee) et l'espaceur (diorganometallique). Ainsi, nous avons obtenu le polymere entierement conjugue. Les essais de complexation restent encore a realiser. Les oligo(3-octylthiophenes) regioreguliers, materiaux ordonnes, possedent des proprietes electrochimiques et optiques interessantes. Differentes caracterisations ont ete effectuees. Le polymere a complexes organometalliques pourra, lui aussi, pretendre a diverses proprietes (magnetiques, valences mixtes ou photophysiques)
23
Tavares, Lucas Alves. "O envolvimento da proteína adaptadora 1 (AP-1) no mecanismo de regulação negativa do receptor CD4 por Nef de HIV-1." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17136/tde-06012017-113215/.
Full textAbstract:
O Vírus da Imunodeficiência Humana (HIV) é o agente etiológico da Síndrome da Imunodeficiência Adquirida (AIDS). A AIDS é uma doença de distribuição mundial, e estima-se que existam atualmente pelo menos 36,9 milhões de pessoas infectadas com o vírus. Durante o seu ciclo replicativo, o HIV promove diversas alterações na fisiologia da célula hospedeira a fim de promover sua sobrevivência e potencializar a replicação. A rápida progressão da infecção pelo HIV-1 em humanos e em modelos animais está intimamente ligada à função da proteína acessória Nef. Dentre as diversas ações de Nef está a regulação negativa de proteínas importantes na resposta imunológica, como o receptor CD4. Sabe-se que esta ação resulta da indução da degradação de CD4 em lisossomos, mas os mecanismos moleculares envolvidos ainda são totalmente elucidados. Nef forma um complexo tripartite com a cauda citosólica de CD4 e a proteína adaptadora 2 (AP-2), em vesículas revestidas por clatrina nascentes, induzindo a internalização e degradação lisossomal de CD4. Pesquisas anteriores demonstraram que o direcionamento de CD4 aos lisossomos por Nef envolve a entrada do receptor na via dos corpos multivesiculares (MVBs), por um mecanismo atípico, pois, embora não necessite da ubiquitinação de carga, depende da ação de proteínas que compõem os ESCRTs (Endosomal Sorting Complexes Required for Transport) e da ação de Alix, uma proteína acessória da maquinaria ESCRT. Já foi reportado que Nef interage com subunidades dos complexos AP-1, AP-2, AP-3 e Nef não parece interagir com subunidades de AP-4 e AP-5. Entretanto, o papel da interação de Nef com AP-1 e AP-3 na regulação negativa de CD4 ainda não está totalmente elucidado. Ademais, AP-1, AP-2 e AP-3 são potencialmente heterogêneos devido à existência de isoformas múltiplas das subunidades codificadas por diferentes genes. Todavia, existem poucos estudos para demonstrar se as diferentes combinações de isoformas dos APs são formadas e se possuem propriedades funcionais distintas. O presente trabalho procurou identificar e caracterizar fatores celulares envolvidos na regulação do tráfego intracelular de proteínas no processo de regulação negativa de CD4 induzido por Nef. Mais especificamente, este estudo buscou caracterizar a participação do complexo AP-1 na modulação negativa de CD4 por Nef de HIV-1, através do estudo funcional das duas isoformas de ?-adaptina, subunidades de AP-1. Utilizando a técnica de Pull-down demonstramos que Nef é capaz de interagir com ?2. Além disso, nossos dados de Imunoblot indicaram que a proteína ?2-adaptina, e não ?1-adaptina, é necessária no processo de degradação lisossomal de CD4 por Nef e que esta participação é conservada para degradação de CD4 por Nef de diferentes cepas virais. Ademais, por citometria de fluxo, o silenciamento de ?2, e não de ?1, compromete a diminuição dos níveis de CD4 por Nef da membrana plasmática. A análise por imunofluorêsncia indireta também revelou que a diminuição dos níveis de ?2 impede a redistribuição de CD4 por Nef para regiões perinucleares, acarretando no acúmulo de CD4, retirados por Nef da membrana plasmática, em endossomos primários. A depleção de ?1A, outra subunidade de AP-1, acarretou na diminuição dos níveis celulares de ?2 e ?1, bem como, no comprometimento da eficiente degradação de CD4 por Nef. Além disso, foi possível observar que, ao perturbar a maquinaria ESCRT via super-expressão de HRS (uma subunidade do complexo ESCRT-0), ocorreu um acumulo de ?2 em endossomos dilatados contendo HRS-GFP, nos quais também detectou-se CD4 que foi internalizado por Nef. Em conjunto, os resultados indicam que ?2-adaptina é uma importante molécula para o direcionamento de CD4 por Nef para a via ESCRT/MVB, mostrando ser uma proteína relevante no sistema endo-lisossomal. Ademais, os resultados indicaram que as isoformas ?-adaptinas não só possuem funções distintas, mas também parecem compor complexos AP-1 com diferentes funções celulares, já que apenas a variante AP-1 contendo ?2, mas não ?1, participa da regulação negativa de CD4 por Nef. Estes estudos contribuem para o melhor entendimento dos mecanismos moleculares envolvidos na atividade de Nef, que poderão também ajudar na melhor compreensão da patogênese do HIV e da síndrome relacionada. Em adição, este trabalho contribui para o entendimento de processos fundamentais da regulação do tráfego de proteínas transmembrana no sistema endo-lisossomal.<br>The Human Immunodeficiency Virus (HIV) is the etiologic agent of Acquired Immunodeficiency Syndrome (AIDS). AIDS is a disease which has a global distribution, and it is estimated that there are currently at least 36.9 million people infected with the virus. During the replication cycle, HIV promotes several changes in the physiology of the host cell to promote their survival and enhance replication. The fast progression of HIV-1 in humans and animal models is closely linked to the function of an accessory protein Nef. Among several actions of Nef, one is the most important is the down-regulation of proteins from the immune response, such as the CD4 receptor. It is known that this action causes CD4 degradation in lysosome, but the molecular mechanisms are still incompletely understood. Nef forms a tripartite complex with the cytosolic tail of the CD4 and adapter protein 2 (AP-2) in clathrin-coated vesicles, inducing CD4 internalization and lysosome degradation. Previous research has demonstrated that CD4 target to lysosomes by Nef involves targeting of this receptor to multivesicular bodies (MVBs) pathway by an atypical mechanism because, although not need charging ubiquitination, depends on the proteins from ESCRTs (Endosomal Sorting Complexes Required for Transport) machinery and the action of Alix, an accessory protein ESCRT machinery. It has been reported that Nef interacts with subunits of AP- 1, AP-2, AP-3 complexes and Nef does not appear to interact with AP-4 and AP-5 subunits. However, the role of Nef interaction with AP-1 or AP-3 in CD4 down-regulation is poorly understood. Furthermore, AP-1, AP-2 and AP-3 are potentially heterogeneous due to the existence of multiple subunits isoforms encoded by different genes. However, there are few studies to demonstrate if the different combinations of APs isoforms are form and if they have distinct functional properties. This study aim to identify and characterize cellular factors involved on CD4 down-modulation induced by Nef from HIV-1. More specifically, this study aimed to characterize the involvement of AP-1 complex in the down-regulation of CD4 by Nef HIV-1 through the functional study of the two isoforms of ?-adaptins, AP-1 subunits. By pull-down technique, we showed that Nef is able to interact with ?2. In addition, our data from immunoblots indicated that ?2- adaptin, not ?1-adaptin, is required in Nef-mediated targeting of CD4 to lysosomes and the ?2 participation in this process is conserved by Nef from different viral strains. Furthermore, by flow cytometry assay, ?2 depletion, but not ?1 depletion, compromises the reduction of surface CD4 levels induced by Nef. Immunofluorescence microscopy analysis also revealed that ?2 depletion impairs the redistribution of CD4 by Nef to juxtanuclear region, resulting in CD4 accumulation in primary endosomes. Knockdown of ?1A, another subunit of AP-1, resulted in decreased cellular levels of ?1 and ?2 and, compromising the efficient CD4 degradation by Nef. Moreover, upon artificially stabilizing ESCRT-I in early endosomes, via overexpression of HRS, internalized CD4 accumulates in enlarged HRS-GFP positive endosomes, where co-localize with ?2. Together, the results indicate that ?2-adaptin is a molecule that is essential for CD4 targeting by Nef to ESCRT/MVB pathway, being an important protein in the endo-lysosomal system. Furthermore, the results indicate that ?-adaptins isoforms not only have different functions, but also seem to compose AP-1 complex with distinct cell functions, and only the AP-1 variant comprising ?2, but not ?1, acts in the CD4 down-regulation induced by Nef. These studies contribute to a better understanding on the molecular mechanisms involved in Nef activities, which may also help to improve the understanding of the HIV pathogenesis and the related syndrome. In addition, this work contributes with the understanding of primordial process regulation on intracellular trafficking of transmembrane proteins.
24
Meller, Rafał. "Dwustronne oszacowanie momentów wieloliniowych form losowych - przypadek rzeczywisty i wektorowy." Doctoral thesis, 2020. https://depotuw.ceon.pl/handle/item/3657.
Full textAbstract:
In the following thesis we are investigating random multilinear forms, which are called random chaoses, defined by S := X i1,...,id ai1,...,idXi1···Xid, where d∈N, X1,...,Xn are independent random variables, and ai1,...,id ∈F, where (F,k·k) is a Banach space. We want to derive two-sided bounds of kSkp :=(EkSkp)1/p under some conditions about the structure of (ai1,...,id)i1,...,id and the distribution of (X1,X2,...). The first part of the thesis concerns the case when F =R (the real case). In the first chapter we assume that the random variables X1,X2,... are nonnegative and their moments do not grow "too fast". In the second chapter we consider the symmetric random variables satisfying the same moment condition. The second part is dedicated to vector-valued chaoses. We derive certain upper bounds which turn out to be two-sided in a special class of Banach spaces (which includes Lq spaces). In the third and fourth chapters we analyze the case when the random variables X1,X2,... have Gaussian distributionand d=2or d>2respectively.Inthefifthchapterwestudyvariableswithlog-concave tails and d=2. AMS 2000 subject classifications: Primary: 60E15. Secondary: 60B11.<br>Niniejsza rozprawa poświęcona jest losowym formom wieloliniowym, zwanym chaosami losowymi, które są zdefiniowane jako S := X i1,...,id ai1,...,idXi1···Xid, gdzie d ∈N, X1,...,Xn są niezależnymi zmiennymi losowymi natomiast ai1,...,id są współczynnikami z przestrzeni Banacha (F,k·k). Naszym celem jest znalezienie dwustronnych oszacowań momentów całkowych zmiennej S określonych jako kSkp :=(EkSkp)1/p. Będziemy przy tym zakładać pewne warunki o strukturze współczynników (ai1,...,id)i1,...,id oraz o rozkładzie zmiennych losowych (X1,X2,...). W pierwszej części pracy rozważamy przypadek gdy F =R (przypadek rzeczywisty). W pierwszym rozdziale zakładamy, że zmienne losowe X1,X2,... są nieujemne oraz, że momenty tych zmiennych nie rosną "za szybko". W drugim rozdziale rozważamy symetryczne zmienne losowe, które spełniają ten sam warunek na wzrost momentów. Druga część pracy poświęcona jest przypadkowi chaosów losowych o wartościach wektorowych. Wyprowadzamy górne oszacowania na momenty, które można odwrócić w pewnej klasie przestrzeni Banacha (zawierającej przestrzenie Lq). Trzeci i czwarty rozdział poświęcony jest przypadkowi, gdy zmienne X1,X2,... mają rozkład normalny oraz, gdy odpowiednio d=2 i d >2. W ostatnim rozdziale omówiony jest przypadek zmiennych losowych o logarytmicznie wklęsłych ogonach oraz d=2.
25
"Two-Tail Non-Linear Moving Tape Displays." Master's thesis, 2012. http://hdl.handle.net/2286/R.I.15039.
Full textAbstract:
abstract: Fixed-pointer moving-scale tape displays are a compact way to present wide range dynamic data, and are commonly employed in aircraft and spacecraft to display the primary parameters of airspeed, altitude and heading. A limitation of the moving tape format is its inability to natively display off scale target, reference or 'bug' values. The hypothesis tested was that a non-linear fisheye presentation (made possible by modern display technology) would maintain the essential functionality and compactness of existing moving tape displays while increasing situational awareness by ecologically displaying a wider set of reference values. Experimentation showed that the speed and accuracy of reading the center system value was not significantly changed with two types of expanded range displays. The limited situational awareness tests did not show a significant improvement with the new displays, but since no functionality was degraded further testing of expanded range displays may be productive.<br>Dissertation/Thesis<br>M.S. Applied Psychology 2012
26
Daniel, Donald L. "A tail of two ends 5 ́and 3 ́modifications of mRNAs and their functional significance /." 1997. http://catalog.hathitrust.org/api/volumes/oclc/37571577.html.
Full text
27
Lu, Yu-Ren, and 盧俞任. "Portfolio Optimization Under Conditional Value at Risk and Tail isk: Based on Two-Stage Stochastic Linear Programming Model." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/61408191884791332618.
Full textAbstract:
碩士<br>中原大學<br>工業與系統工程研究所<br>97<br>In response to the high degree uncertainty of financial market, how to estimate the potential loss of portfolio is the most important topic concerned by investors when they are pursuing the maximum of reward.
Due to the return rate and risk of asset in stock are full of uncertainty, investors will face more complex investment problems than usual. In this thesis, we apply the modified Conditional Value-at-Risk (CVaR) model to be uncertainty to select the portfolio with riskless. Although CVaR be used in finance perform well, the portfolio that select by it is still risky. Therefore, in order to avoid any intensity fluctuates of risk, we structure our model based on safety-first model to control downside risk.
In this thesis we compare two relative linear programming models for solving the single period portfolio selection problem. The first model is considered a stochastic linear programming (SLP) model by using minimization of Conditional Value-at-Risk as objective function, and constrain is structured by safety-first model. The second is based on safety-first model using original data. However, test results of ours performances are better than market and the safety-first model with original data.
28
ZHEN, REN-JIE, and 鄭仁杰. "A two-dimensional unstructured Euler/Navier-Stokes solver and its application to the flutter analysis of wing-tail configurations." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/91641332317078537796.
Full text
29
Schaefer, Moritz. "Cysteine residues of the mammalian GET receptor: Essential for tail-anchored protein insertion?" Doctoral thesis, 2017. http://hdl.handle.net/11858/00-1735-0000-0023-3E49-D.
Full text
30
Yang, Kefei. "Functional Analysis of Two Major Sperm Tail Proteins Identifies ODF1 as Being Essential for the Tight Linkage of the Sperm Head to the Tail via SPAG4 and ODF2 as A Component of the β-catenin Destruction Complex". Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0022-5FA2-A.
Full text
31
Huang, Yi-ching, and 黃益青. "The Study of Network Recommendation Method in Long Tail Market''s Two Sides Application: Take Taiwan''s Digital Music Industry as an Example." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/84242134743483930509.
Full textAbstract:
碩士<br>逢甲大學<br>企業管理所<br>96<br>Web2.0 is the contour and new game rule of latter network world. Long Tail is the network marketing criterion and new economics of the culture creative industry in Web2.0 world. The music industry changed rapidly in the last decade, and the product sales changed from physical CD disks to digital music. All industry emerged from the new patterns in essential and operational. The proposes of the research are to explore (1) the fit of latter Taiwan''s digital music industry application in Web2.0 and Long Tail; (2) the recommendation effect of the network recommendation method in that; (3) the future developing tendency in digital music industry.
Through the exploration of research questions with perspectives of bibliographical conferring, this research divides consumers'' preferences of the top mass market and the rear niche market into audiences of pop music and niche music. The types of latter digital music divide into three types: P2P Files Exchange, Streaming and Charge for Downloading. Network recommendation method divide equally emphasized basis of media and information in marketing effect into two dimensions: the message''s media sources and the recommendation message''s delivery.
Through in-depth interview, this research has discovered that (1) P2P Files Exchange is the most prevalent channel of consumers'' illegal downloading music; (2) Streaming has developed to the popular legal digital music; (3) it''s hard to survive due to Charge for Downloading is too expensive. Furthermore, the consumers of preferring niche music have better accepted recommendation effect to (1) the message''s media sources of higher autonomous content; (2) the recommendation message''s delivery of higher individual controlling content.
32
Chutter, Ashley. "Elemental abundance investigation of two candidate extragalactic globular clusters (NGC 5024, NGC 5466)." Thesis, 2008. http://hdl.handle.net/1828/1355.
Full textAbstract:
High resolution spectra have been analyzed for two and three stars respectively in the candidate extragalactic globular clusters, NGC 5024 and NGC 5466, with the High-Resolution Spectrograph on the 9.2 m Hobby-Eberly Telescope. The goal of this investigation is to evaluate the proposed extragalactic origins of these two globular clusters. Evidence of a tidal tail in NGC 5466 (Belokurov et al., 2006) and the association of NGC 5024 with the Sagittarius stream (Martinez-Delgado et al., 2004) targeted the clusters as likely remnants of recent accretion events and thus potentially of extragalactic origin. Determination of their chemical abundance patterns could provide unique evidence to either support or dispute these claims. NGC 5024 has been associated with a proposed wrap in the Sagittarius stream which could be supported if the chemistry of NGC 5024 is similar to other clusters associated with the stream. NGC 5466 has the longest tidal tail known, which hints at an origin in a now dispersed dwarf spheroidal galaxy. Additional evidence for these clusters' capture origins has been compiled by Yoon & Lee (2002), demonstrating that these two low metallicity clusters, along with five others, are aligned in a single highly inclined plane in the outer halo. Confirmation that these clusters are remnants of dwarf galaxies would support a Galactic history which includes recent accretion events. Such evidence may bolster the cold dark matter hierarchical clustering scenario, which postulates the presence of a significant amount of substructure in the Milky Way.
Unfortunately, at the metallicity of the target clusters ([Fe/H] = -1.9), the chemical distinction between Galactic stars and known dSph stars is not significant. The low [alpha/Fe] of dSph stars seen at higher metallicity is not apparent at [Fe/H] = -1.9 in either Galactic or dSph stars. Aside from a few mild discrepancies, NGC 5024 and NGC 5466 appear chemically similar to the Galactic field stars and globular clusters compiled by Pritzl et al. (2005). A moderate enhancement in the [Ba/Y] ratios relative to the halo field stars is the only positively detected chemical signature that is typically observed in dSph stars. Comparisons with Galactic GCs of similar age, metallicity and horizontal branch morphology (NGC 2298, NGC 6397 and NGC 5897) reveal a few other differences, but these could be attributed to systematic effects in the different analysis techniques. Although NGC 5024 has a similar metallicity to the GC Arp 2 that was stripped from the merging Sagittarius dwarf, neither Arp 2 (Mottini et al., 2008) nor the clusters in this study show any particularly unusual chemical abundance patterns. Thus, no conclusive evidence in support of or in opposition to the target clusters' proposed extragalactic origins has been discovered.
33
Scafone, Teresa, Lucio Grandinetti, and Dina Bellizzi. "Study of two epigenetic age-associated modifications: DNA methylation of the rRNA gene promoter in humans and histone tail acetylation at the subtelomeric region in S. cerevisiae." Thesis, 2014. http://hdl.handle.net/10955/1250.
Full textAbstract:
PhD Program in Operation Research XXVII Ciclo a.a. 2014<br>Il presente lavoro di tesi è stato realizzato in parte presso il laboratorio di genetica dell'Università della Calabria, sotto la supervisione della Professoressa Dina Bellizzi e in parte presso la Davis School of Gerontology, in collaborazione con il Professor Valter Longo direttore del USC Longevity Institute.
L'invecchiamento è un processo complesso. I fenotipi d’invecchiamento variano da organismo a organismo, ma un generale declino fisiologico si realizza con l’avanzare dell'età.
Una correlazione tra modificazioni epigenetiche e invecchiamento è stato proposto molti anni fa, e nel corso degli anni molteplici studi hanno fornito le prove dell’esistenza di tale connessione, suggerendo che si tratta di un fenomeno conservato lungo il processo evolutivo. In questo lavoro sono stati investigati due dei più importanti meccanismi epigenetici associati all’invecchiamento: la metilazione del DNA e l’acetilazione degli istoni.
È noto che a livello globale la metilazione del DNA tende a diminuire nel corso dell’invecchiamento, con un concomitante aumento, invece, ai promotori di specifici geni. Presso il laboratorio di genetica dell’Università della Calabria è stata investigata la presenza di citosine metilate in siti CpG all’interno della regione del promotore dei geni che codificano per l’RNA ribosomiale umano nonché l’associazione tra tali livelli, l’invecchiamento e la frailty.
L’attenzione è stata focalizzata su questo sito a causa di alcune peculiari caratteristiche che esso presenta: il ruolo cruciale dell’rRNA ribosomiale nelle funzioni cellulari, l’alto livello di conservazione di questa sequenza nucleotidica lungo il processo evolutivo, nonchè l’organizzazione in cluster dei geni che codificano per l’rRNA.
I livelli di metilazione sono stati valutati in campioni di sangue estratti da individui di età differente e con differenti fenotipi d’invecchiamento mediante la piattaforma Sequenom MassARRAY EpiTYPER. Dall’analisi è emersa l’esistenza di una correlazione tra i livelli di metilazione di specifici dinucleotidi CpG, presenti nel promotore genico da noi investigato, l’invecchiamento e i diversi fenotipi ad esso correlati. I risultati di questo studio sono mostrati nel Capitolo 2.
Studiare l’invecchiamento negli esseri umani, tuttavia, comporta numerose difficoltà, per questa ragione sono spesso utilizzati sistemi modello. Uno dei più importanti organismi modello è il lievito Saccharomyces cerevisiae attraverso cui è stato possibile individuare numerosi geni rilevanti nel processo di invecchiamento, tra cui il gene Sir2 che codifica per un’istone deacetilasi.
Sir2 è un gene associato con resistenza cellulare allo stress e con la regolazione della durata della vita sia replicativa che cronologica nel lievito. Presso il laboratorio del Prof. Longo è stato in precedenza dimostrato che Sir2 blocca l’estensione della durata della vita cronologica causata dalla restrizione calorica o da mutazioni nei pathway Tor/Sch9, Ras/cAMP/PKA e promuove, inoltre, la protezione cellulare sia contro lo stress termico che ossidativo.
Evidenze crescenti dimostrano che Sir2 e la sua controparte, Sas2, regolano la durata della vita di S. cerevisiae mediante acetilazione e deacetilazione degli istoni H4K16 nella regione sub-telomerica. In questo studio, abbiamo identificato un nuovo meccanismo attraverso cui Sir2, agendo sulla regione sub-telomerica, regola la protezione contro il danno ossidativo, senza influenzare l'invecchiamento cronologico, segno che questi eventi sono regolati da pathway differenti. I dati riportati supportano i risultati ottenuti in precedenza e allo stesso tempo forniscono una spiegazione parziale del meccanismo sottostante alla maggiore resistenza mostrata dalle cellule mancanti del gene Sir2, come riportato nel Capitolo 3.
Durante il periodo trascorso presso i laboratori del Longevity Institute sono stata inoltre coinvolta in un secondo progetto, dimostrando che una dieta ipocalorica e non solo il digiuno sono efficaci nel ridurre la progressione tumorale e gli effetti collaterali associati alla chemioterapia, identificando inoltre nel sistema immunitario un attore fondamentale di questo processo. Data la rilevanza di questi dati, la USC si riserva la possibilità di bloccarne la divulgazione prima della pubblicazione. Tuttavia, una breve descrizione di questo lavoro è fornita in appendice A.
Nella prima parte del mio programma di dottorato di ricerca, condotta presso l'Università della Calabria, ho inoltre collaborato ad uno studio volto a risolvere il dibattito circa la possibile presenza di citosine metilate all'interno del DNA mitocondriale (mtDNA). I risultati di questo studio sono illustrati nell’articolo scientifico “The Control Region of Mitochondrial DNA Shows an Unusual CpG and Non-CpG Methylation Pattern”, DNA Research, riportato in appendice B.<br>University of Calabria
34
Malinowski, Alexander. "Financial Models of Interaction Based on Marked Point Processes and Gaussian Fields." Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-000D-F0EF-6.
Full text
35
Hannich, Theresa. "Digital transformation in the german sports broadcasting industry : a qualitative study on the impact of the disruptor OTT." Master's thesis, 2020. http://hdl.handle.net/10400.14/31131.
Full textAbstract:
The study investigates the impact of the OTT (over-the-top) technology for the German sports broadcasting industry. For this purpose of the study, OTT is defined as streaming technology that bypasses traditional distribution and offers content directly over the Internet anywhere at any time. All potential OTT initiatives from different stakeholders that impact the industry are examined.
The incumbent technology, traditional TV, is challenged by innovative business models that provide sports content over-the-top via the Internet. Pure OTT channels such as DAZN and digital giants such as Amazon entered the sports rights market forcing old leaders to rethink their business model and to adapt to the new technology.
Besides of changing consumer requirements, different market dynamics such as the digitization of sports rights, the trend towards D2C (direct-to-consumer), niche targeting and features around digital fan experiences push OTT in becoming the leading sports consumption technology.
The fast-paced and vibrant market movements in the sports media industry make estimations difficult. The findings from qualitative and quantitative findings identified the consolidation of the market to a concentrated number of content aggregators operating in the premium sports right segment as most the likely scenario for the industry in 5-10 years. This trend goes along with a starting content endgame initiated by top rightsholders who implement D2C business models for secondary markets. The major change in the market will be the end of market fragmentation to a more consolidated sports rights market led by major D2C and OTT platforms.<br>O estudo investiga o impacto da tecnologia OTT (over-the-top) para a indústria alemã de transmissão desportiva. Para este efeito do estudo, a OTT é definida como uma tecnologia de streaming que ultrapassa a distribuição tradicional e oferece conteúdos diretamente através da Internet, em qualquer lugar e a qualquer momento.
A tecnologia já existente de televisão tradicional é desafiada por modelos de negócio inovadores que fornecem conteúdos desportivos através da Internet. Os canais OTT puros como o DAZN e gigantes digitais como a Amazon entraram no mercado dos direitos desportivos, obrigando os antigos líderes a repensar o seu modelo de negócio.
Além da modificação das exigências dos consumidores, diferentes dinâmicas de mercado, como a digitalização dos direitos desportivos, a tendência para D2C (direct-to-consumer), a segmentação de nichos de mercado e as características em torno das experiências digitais dos adeptos, impulsionam a OTT a tornar-se a tecnologia de consumo desportivo líder.
No entanto, as conclusões dos resultados qualitativos e quantitativos identificaram a consolidação do mercado para um número concentrado de agregadores de conteúdos que operam no segmento dos direitos desportivos premium como o cenário mais provável para a indústria dentro de 5-10 anos. Esta tendência vai de par com um jogo final de conteúdos iniciado pelos titulares de direitos de topo que implementam modelos de negócio D2C para os mercados secundários. A grande mudança no mercado será o fim da fragmentação do mercado para um mercado de direitos desportivos mais consolidado, liderado pelas principais plataformas D2C e OTT.