(Table T4) Final depth vs. velocity and two-way traveltime data, ODP Site 178-1103

Site 1103 was one of a transect of three sites drilled across the Antarctic Peninsula continental shelf during Leg 178. The aim of drilling on the shelf was to determine the age of the sedimentary sequences and to ground truth previous interpretations of the depositional environment (i.e., topsets and foresets) of progradational seismostratigraphic sequences S1, S2, S3, and S4. The ultimate objective was to obtain a better understanding of the history of glacial advances and retreats in this west Antarctic margin. Drilling the topsets of the progradational wedge (0-247 m below seafloor [mbsf]), which consist of unsorted and unconsolidated materials of seismic Unit S1, was very unfavorable, resulting in very low (2.3%) core recovery. Recovery improved (34%) below 247 mbsf, corresponding to sediments of seismic Unit S3, which have a consolidated matrix. Logs were only obtained from the interval between 75 and 244 mbsf, and inconsistencies on the automatic analog picking of the signals received from the sonic log at the array and at the two other receivers prevented accurate shipboard time-depth conversions. This, in turn, limited the capacity for making seismic stratigraphic interpretations at this site and regionally. This study is an attempt to compile all available data sources, perform quality checks, and introduce nonstandard processing techniques for the logging data obtained to arrive at a reliable and continuous depth vs. velocity profile. We defined 13 data categories using differential traveltime information. Polynomial exclusion techniques with various orders and low-pass filtering reduced the noise of the initial data pool and produced a definite velocity depth profile that is synchronous with the resistivity logging data. A comparison of the velocity profile produced with various other logs of Site 1103 further validates the presented data. All major logging units are expressed within the new velocity data. A depth-migrated section with the new velocity data is presented together with the original time section and initial depth estimates published within the Leg 178 Initial Reports volume. The presented data confirms the location of the shelf unconformity at 222 ms two-way traveltime (TWT), or 243 mbsf, and allows its seismic identification as a strong negative and subsequent positive reflection.

An auction theoretical approach to fiscal wars

I examine a situation where a firm chooses to locate a new factory in one of several jurisdictions. The value of the factory may differ among jurisdictions and it depends on the private information held by each jurisdiction. Jurisdictions compete for the location of the new factory. This competition may take the form of expenditures already incurred on infrastructure, commitments to spend on infrastructure, tax incentives or even cash payments. The model combines two elements that are usually considered separately; competition is desirable because we want the factory to be located in the jurisdiction that values it the most, but competition in itself is wasteful. I show that the expected total amount paid to the firm under a large family of arrangements is the same. Moreover, I show that the ex-ante optimal mechanism that is, the mechanism that guarantees that the firm chooses the jurisdiction with the highest value for the factory, minimizes the total expected payment to the firm, and balances the budget in an ex-ante sense - can be implemented by running a standard auction and subsidizing participation.

Adhesively-bonded repair proposal for wood members damaged by horizontal shear using carbon-epoxy patches

In this work, a repair technique with adhesively bonded carbon-epoxy patches is proposed for wood members damaged by horizontal shear and under bending loads. This damage is characterized by horizontal crack growth near the neutral plane of the wood beam, normally originating from checks and shakes. The repair consists of adhesively bonded carbon-epoxy patches on the vertical side faces of the beam at the cracked region to block sliding between the beam arms. An experimental and numerical parametric analysis was performed on the patch length. The numerical analysis used the finite element method (FEM) and cohesive zone models (CZMs), with an inverse modelling technique for the characterization of the adhesive layer. Trapezoidal cohesive laws in each pure mode were used to account for the ductility of the adhesive used. To fully reproduce the tests, horizontal damage propagation within the wood beam was also simulated. A good correlation with the experiments was found. Regarding the effectiveness of the repair, for the conditions selected for this work, a full strength recovery was achieved for the bigger value of patch length tested.

Comparing clustering solutions: the use of adjusted paired indices

In the present paper we compare clustering solutions using indices of paired agreement. We propose a new method - IADJUST - to correct indices of paired agreement, excluding agreement by chance. This new method overcomes previous limitations known in the literature as it permits the correction of any index. We illustrate its use in external clustering validation, to measure the accordance between clusters and an a priori known structure. The adjusted indices are intended to provide a realistic measure of clustering performance that excludes agreement by chance with ground truth. We use simulated data sets, under a range of scenarios - considering diverse numbers of clusters, clusters overlaps and balances - to discuss the pertinence and the precision of our proposal. Precision is established based on comparisons with the analytical approach for correction specific indices that can be corrected in this way are used for this purpose. The pertinence of the proposed correction is discussed when making a detailed comparison between the performance of two classical clustering approaches, namely Expectation-Maximization (EM) and K-Means (KM) algorithms. Eight indices of paired agreement are studied and new corrected indices are obtained.

Análise do desempenho na administração pública com recurso a rácios financeiros

O objetivo geral deste trabalho é a Análise do Desempenho na Administração Pública com recurso a Rácios Financeiros (Caso do Município de Matosinhos). Neste estudo iremos fazer uma análise económica e financeira do Município de Matosinhos avaliando seu o desempenho nos períodos de 2011 a 2014 e também, iremos analisar alguns fatores que influenciam a estrutura de capital dos 12 Municípios de grande dimensão e o seu desempenho. Quanto à análise económica e financeira do Município de Matosinhos, os resultados mostram, que a curto prazo é possível afirmar que o Município de Matosinhos se encontra numa situação favorável em termos de liquidez, com uma boa margem de segurança, ou seja, consegue solver os compromissos a curto. Verifica-se que o Município de Matosinhos ao longo do quadriénio foi recorrendo cada vez menos a capitais alheios para conseguir financiar os seus ativos, tendência positiva em termos do equilíbrio da estrutura financeira municipal. Tentando confirmar a existência ou inexistência de uma relação entre a estrutura de capital (endividamento) e o desempenho (rendibilidade do ativo) com os fatores que as influenciam, foi realizada uma análise de correlação não paramétrica de Spearman com recurso ao SPSS versão 21. Ao contrário da hipótese formulada e das conclusões chegadas em grande parte dos estudos efetuados, verifica-se a existência de uma relação negativa a um nível de significância de 5%, entre o nível de endividamento e a dimensão do Município. Quanto a relação o entre o endividamento com composição do ativo e a rendibilidade do ativo, os resultados não são satisfatórios, mostram uma inexistência da relação entre o endividamento e esses fatores. Verifica-se uma correlação positiva para um nível de significância de 1% entre a rendibilidade do ativo e crescimento, ou seja, os Municípios com maior taxa de crescimento apresentam uma maior rendibilidade do ativo. Este resultado confirma-se a nossa hipótese 4. Porém, em relação a associação positiva entre a rendibilidade do Município e a sua dimensão, os resultados evidenciaram uma inexistência de qualquer relação entre as variáveis.

Effectiveness of brief alcohol interventions in primary care populations.

Excessive drinking contributes significantly to social problems, physical and psychological illness, injury and death. Hidden effects include increased levels of violence, accidents and suicide. Most alcohol-related harm is caused by excessive drinkers whose consumption exceeds recommended drinking levels, not the drinkers with severe alcohol dependency problems. One way to reduce consumption levels in a community may be to provide a brief intervention in primary care over one to four sessions. This is provided by healthcare workers such as general physicians, nurses or psychologists. In general practice, patients are routinely asked about alcohol consumption during registration, general health checks and as part of health screening (using a questionnaire). They tend not to be seeking help for alcohol problems when presenting. The intervention they are offered includes feedback on alcohol use and harms, identification of high risk situations for drinking and coping strategies, increased motivation and the development of a personal plan to reduce drinking. It takes place within the time-frame of a standard consultation, 5 to 15 minutes for a general physician, longer for a nurse.A total of 29 controlled trials from various countries were identified, in general practice (24 trials) or an emergency setting (five trials). Participants drank an average of 306 grams of alcohol (over 30 standard drinks) per week on entry to the trial. Over 7000 participants with a mean age of 43 years were randomised to receive a brief intervention or a control intervention, including assessment only. After one year or more, people who received the brief intervention drank less alcohol than people in the control group (average difference 38 grams/week, range 23 to 54 grams). For men (some 70% of participants), the benefit of brief intervention was a difference of 57 grams/week, range 25 to 89 grams (six trials). The benefit was not clear for women. The benefits of brief intervention were similar in the normal clinical setting and in research settings with greater resources. Longer counselling had little additional benefit.This resource was contributed by The National Documentation Centre on Drug Use.

Stringless Portland Cement Concrete Paving, February 2004

This report describes results from a study evaluating the use of stringless paving using a combination of global positioning and laser technologies. CMI and Geologic Computer Systems developed this technology and successfully implemented it on construction earthmoving and grading projects. Concrete paving is a new area for considering this technology. Fred Carlson Co. agreed to test the stringless paving technology on two challenging concrete paving projects located in Washington County, Iowa. The evaluation was conducted on two paving projects in Washington County, Iowa, during the summer of 2003. The research team from Iowa State University monitored the guidance and elevation conformance to the original design. They employed a combination of physical depth checks, surface location and elevation surveys, concrete yield checks, and physical survey of the control stakes and string line elevations. A final check on profile of the pavement surface was accomplished by the use of the Iowa Department of Transportation Light Weight Surface Analyzer (LISA). Due to the speed of paving and the rapid changes in terrain, the laser technology was abandoned for this project. Total control of the guidance and elevation controls on the slip-form paver were moved from string line to global positioning systems (GPS). The evaluation was a success, and the results indicate that GPS control is feasible and approaching the desired goals of guidance and profile control with the use of three dimensional design models. Further enhancements are needed in the physical features of the slipform paver oil system controls and in the computer program for controlling elevation.

A Ética e a transparência na Administração Pública Caboverdiana

A nossa sociedade está, visivelmente, em busca de padrões éticos, de padrões de melhoria social, de padrões de melhoria económica. Acredita-se, pois que a ética e a transparência podem se constituir em elementos essenciais no sentido de assegurar que qualquer governo atinja os seus objectivos com eficiência, efectividade e dentro dos preceitos legais da ordem democrática. Tendo o Governo de Cabo Verde eleito a ética e a transparência na gestão da coisa pública como fundamentos de uma “boa governação”, é imprescindível criar mecanismos de controlo, a fim de verificar se tal determinação está sendo efectivada. Para tanto, é fundamental que haja, uma análise criteriosa, considerando não só os aspectos da administração, mas principalmente, os aspectos políticos e sociais envolvidos. Isto se justifica, ademais, pelo facto de haver mais eficiência governativa quando as instituições funcionam com regras, com transparência, com ética, com comprometimento ao serviço público, com profissionalismo e quando estão sujeitas ao controlo social e aos mecanismos de "check and balances". Em Cabo Verde existe uma assimetria entre o governo, a oposição, e a sociedade no que diz respeito à ética e à transparência na Administração Pública. Esta constatação nos motivou a efectuar uma reflexão sobre o assunto, não no intuito de julgar mas, sim, de pesquisar os actos e as regras praticadas na Administração Pública Cabo-verdiana, ou seja, pelo Poder Executivo Cabo-Verdiano, posto que tais actos, em última instância, visam assegurar o alcance do bem comum no âmbito referido. Assim sendo, o objectivo deste trabalho é reflectir sobre a questão da ética e da transparência na Administração Pública Cabo-verdiana, desenvolvendo um pensamento crítico e fundamentado a respeito do tema. O que se busca, neste caso, é assinalar propostas práticas face ao modelo actual de Reforma Administrativa em Cabo Verde, contribuindo para o seu aperfeiçoamento. Em termos de contexto, realça-se que o estudo abrangerá a vertente da Administração Central. Para alcançar o objectivo deste trabalho, fez-se uma pesquisa bibliográfica sobre a ética e Transparência na Administração Pública e sobre diversas teorias relacionadas com a ética nas organizações. Utilizou-se o método inquisitivo baseado em 5 questionário com perguntas fechadas e abertas para se obter a percepção dos dirigentes, funcionários públicos e utentes da Administração Pública, bem como dos políticos que hoje actuam neste âmbito. Os dados recolhidos proporcionam indicações evidentes que é preciso mudar de paradigma no que diz respeito à Ética e à Transparência na Administração Pública Cabo-verdiana.

ÉTICA E A TRANSPARÊNCIA NA ADMINISTRAÇÃO PÚBLICA CABO-VERDIANA: QUAIS DESAFIOS?

A nossa sociedade está, visivelmente, em busca de padrões éticos, de padrões de melhoria social, de padrões de melhoria económica. Acredita-se, pois que a ética e a transparência podem se constituir em elementos essenciais no sentido de assegurar que qualquer governo atinja os seus objectivos com eficiência, efectividade e dentro dos preceitos legais da ordem democrática. Tendo o Governo de Cabo Verde eleito a ética e a transparência na gestão da coisa pública como fundamentos de uma “boa governação”, é imprescindível criar mecanismos de controlo, a fim de verificar se tal determinação está sendo efectivada. Para tanto, é fundamental que haja, uma análise criteriosa, considerando não só os aspectos da administração, mas principalmente, os aspectos políticos e sociais envolvidos. Isto se justifica, ademais, pelo facto de haver mais eficiência governativa quando as instituições funcionam com regras, com transparência, com ética, com comprometimento ao serviço público, com profissionalismo e quando estão sujeitas ao controlo social e aos mecanismos de "check and balances". Em Cabo Verde existe uma assimetria entre o governo, a oposição, e a sociedade no que diz respeito à ética e à transparência na Administração Pública. Esta constatação nos motivou a efectuar uma reflexão sobre o assunto, não no intuito de julgar mas, sim, de pesquisar os actos e as regras praticadas na Administração Pública Cabo-verdiana, ou seja, pelo Poder Executivo Cabo-Verdiano, posto que tais actos, em última instância, visam assegurar o alcance do bem comum no âmbito referido. Assim sendo, o objectivo deste trabalho é reflectir sobre a questão da ética e da transparência na Administração Pública Cabo-verdiana, desenvolvendo um pensamento crítico e fundamentado a respeito do tema. O que se busca, neste caso, é assinalar propostas práticas face ao modelo actual de Reforma Administrativa em Cabo Verde, contribuindo para o seu aperfeiçoamento. Em termos de contexto, realça-se que o estudo abrangerá a vertente da Administração Central. Para alcançar o objectivo deste trabalho, fez-se uma pesquisa bibliográfica sobre a ética e Transparência na Administração Pública e sobre diversas teorias relacionadas com a ética nas organizações. Utilizou-se o método inquisitivo baseado em 5 questionário com perguntas fechadas e abertas para se obter a percepção dos dirigentes, funcionários públicos e utentes da Administração Pública, bem como dos políticos que hoje actuam neste âmbito. Os dados recolhidos proporcionam indicações evidentes que é preciso mudar de paradigma no que diz respeito à Ética e à Transparência na Administração Pública Cabo-verdiana.

A Ética e a Transparência na Administração Pública Cabo-verdiana: Representações e Questionamentos

A nossa sociedade está, visivelmente, em busca de padrões éticos, de padrões de melhoria social, de padrões de melhoria económica. Nesse sentido, a ética e a transparência na gestão da coisa pública constituem fundamentos indispensáveis para o alcance dos objectivos governamentais com eficiência e efectividade e dentro dos preceitos legais da ordem democrática. Mas o que se verifica em Cabo Verde é a existência de uma assimetria entre o governo, a oposição, e a sociedade no que diz respeito à ética e à transparência na Administração Pública. Esta constatação mais directamente vinculada ao âmbito da Administração Central gerou questionamentos sobre as razões dessa ocorrência, conduzindo a uma reflexão sobre as implicações e os desafios concernentes ao alcance do bem comum no contexto referido. Nesse intuito, buscou-se desenvolver uma análise criteriosa, considerando não só os aspectos da administração, mas principalmente, os aspectos políticos e sociais envolvidos nessa dinâmica. O estudo também se justifica pois denota-se que há maior eficiência governativa quando as instituições funcionam com regras, com transparência, com ética, com comprometimento ao serviço público, com profissionalismo e quando as referidas instituições estão sujeitas ao controlo social e a mecanismos de "check and balances". Assim, com o objetivo de verificar a percepção de dirigentes, políticos, funcionários públicos e utentes da Administração Pública, sobre esta problemática, realizou-se, inicialmente, uma extensa pesquisa bibliográfica acompanhada de análise documental em busca de uma visão fundamentada e crítica sobre o tema em estudo. O levantamento de dados empíricos ocorreu por meio da aplicação, pelo pesquisador, de um questionário com perguntas abertas e fechadas, a um total de sessenta e quatro respondentes assim distribuidos: a) Representantes da Administração Central: Secretaria de Estado da Administração Pública: 9; Ministério da Saúde: 5; Ministério da Educação: 7; Ministério das Finanças: 6; Gabinete do Ministro-Adjunto das Comunidades e Emigração: 5; Ministério da Agricultura: 4; b) Políticos (deputados): 8; c) Utentes da Administração Pública: de um total de 20 respondentes, foi conferida atenção especial aos serviços da Saúde (4 utentes), Educação (4), Finanças (4 utentes), Agricultura (4 utentes) e Secretaria de Estado da Administração Pública (4 utentes). A margem de erro, do ponto de vista da análise estatística dos dados, não ultrapassa os 4% e o coeficiente de confiança é de 95%. Os resutados da análise confirmam a importância do estudo, revelando questões decisivas para o aprofundamento do processo democrático e a conquista da cidadania em Cabo Verde. Dentre estas, há que destacar, por seu impacto na sociedade e no exercício da democracia no contexto referido, os seguintes índices: apenas 6% dos inquiridos consideram a ética e a transparência como novidades no contexto da Reforma do Estado; 64 % aponta a existência de corrupção na gestão da coisa pública; e, por fim, 70,4% dos inquiridos definem como satisfatória a actuação dos funcionários públicos cabo-verdianos no que tange à ética e à transparência na gestão da coisa pública.

Use of Longitudinal Subdrains in the 3R Program, HR-509, Progress Report #2, 1981

The main consideration for base construction under the pavement, in the design of Iowa's interstate, was structural capacity. The material was dense graded with the aim of supporting the pavement and distributing the load as it is transferred to the underlying grade. The drainage characteristics of the base was apparently not given adequate consideration. On jointed portland cement concrete pavement, the water that is trapped immediately beneath the pavement causes severe problems. The traffic causes rapid movement of the water resulting in the hydraulic pressures or "pumping" (movement and redeposit of base fine material), further resulting in faulting between individual slabs. The objective of this evaluation is to determine if longitudinal subdrains are effective in preventing or reducing pumping, faulting and related deterioration. Results suggest that, based upon the flow from the outlets observed during periodic checks and evidence of water flow at the outlets, it appears that to date the subdrains are effective in draining the subbase and subgrade. Because of the limited data available at this time, however, the pavement condition and faulting results are inconclusive.

Use of Longitudinal Subdrains in the 3R Program, Progress Report 1, HR-509, 1980

The main consideration for base construction under the pavement, in the design of Iowa's interstate, was structural capacity. The material was dense graded with the aim of supporting the pavement and distributing the load as it is transferred to the underlying grade. The drainage characteristics of the base was apparently not given adequate consideration. On jointed portland cement concrete pavement, the water that is trapped immediately beneath the pavement causes severe problems. The traffic causes rapid movement of the water resulting in the hydraulic pressures or "pumping" (movement and redeposit of base fine material), further resulting in faulting between individual slabs. The objective of this evaluation is to determine if longitudinal subdrains are effective in preventing or reducing pumping, faulting and related deterioration. Results suggest that, based upon the flow from the outlets observed during periodic checks and evidence of water flow at the outlets, it appears that to date the subdrains are effective in draining the subbase and subgrade. Because of the limited data available at this time, however, the pavement condition and faulting results are inconclusive.

Stringless Portland Cement Concrete Paving, TR-490, 2004

This report describes results from a study evaluating the use of stringless paving using a combination of global positioning and laser technologies. CMI and Geologic Computer Systems developed this technology and successfully implemented it on construction earthmoving and grading projects. Concrete paving is a new area for considering this technology. Fred Carlson Co. agreed to test the stringless paving technology on two challenging concrete paving projects located in Washington County, Iowa. The evaluation was conducted on two paving projects in Washington County, Iowa, during the summer of 2003. The research team from Iowa State University monitored the guidance and elevation conformance to the original design. They employed a combination of physical depth checks, surface location and elevation surveys, concrete yield checks, and physical survey of the control stakes and string line elevations. A final check on profile of the pavement surface was accomplished by the use of the Iowa Department of Transportation Light Weight Surface Analyzer (LISA). Due to the speed of paving and the rapid changes in terrain, the laser technology was abandoned for this project. Total control of the guidance and elevation controls on the slip-form paver were moved from string line to global positioning systems (GPS). The evaluation was a success, and the results indicate that GPS control is feasible and approaching the desired goals of guidance and profile control with the use of three dimensional design models. Further enhancements are needed in the physical features of the slipform paver oil system controls and in the computer program for controlling elevation.

CoDiab-VD: protocol of a prospective population-based cohort study on diabetes care in Switzerland.

BACKGROUND: Diabetes represents an increasing health burden worldwide. In 2010, the Public Health Department of the canton of Vaud (Switzerland) launched a regional diabetes programme entitled "Programme cantonal Diabète" (PcD), with the objectives to both decrease the incidence of diabetes and improve care for patients with diabetes. The cohort entitled CoDiab-VD emerged from that programme. It specifically aimed at following quality of diabetes care over time, at evaluating the coverage of the PcD within this canton and at assessing the impact of the PcD on care of patients with diabetes. METHODS/DESIGN: The cohort CoDiab-VD is a prospective population-based cohort study. Patients with diabetes were recruited in two waves (autumn 2011--summer 2012) through community pharmacies. Eligible participants were non-institutionalised adult patients (≥ 18 years) with diabetes diagnosed for at least one year, residing in the canton of Vaud and coming to a participating pharmacy with a diabetes-related prescription. Women with gestational diabetes, people with obvious cognitive impairment or insufficient command of French were not eligible. Self-reported data collected, included the following primary outcomes: processes-of-care indicators (annual checks) and outcomes of care such as HbA1C, (health-related) quality of life measures (Short Form-12 Health Survey--SF-12, Audit of Diabetes-Dependent Quality of Life 19--ADDQoL) and Patient Assessment of Chronic Illness Care (PACIC). Data on diabetes, health status, healthcare utilisation, health behaviour, self-management activities and support, knowledge of, or participation to, campaigns/activities proposed by the PcD, and socio-demographics were also obtained. For consenting participants, physicians provided few additional pieces of information about processes and laboratory results. Participants will be followed once a year, via a mailed self-report questionnaire. The core of the follow-up questionnaires will be similar to the baseline one, with the addition of thematic modules adapting to the development of the PcD. Physicians will be contacted every 2 years. DISCUSSION: CoDiab-VD will allow obtaining a broad picture of the care of patients with diabetes, as well as their needs regarding their chronic condition. The data will be used to evaluate the PcD and help prioritise targeted actions. TRIAL REGISTRATION: This study is registered with ClinicalTrials.gov, identifier NCT01902043, July 9, 2013.

Environmental control of the Pom1-dependent cell-size regulation pathway in fission yeast

Cells couple their growth and division rate in response to nutrient availability to maintain a constant size. This co-ordination happens either at the G1-S or the G2-M transition of the cell cycle. In the rod-shaped fission yeast, size regulation happens at the G2-M transition prior to mitotic commitment. Recent studies have focused on the role of the DYRK-family protein kinase Pom1, which forms gradients emanating from cell poles and inhibits the mitotic activator kinase Cdr2, present at the cell middle. Pom1 was proposed to inhibit Cdr2 until cells reached a critical size before division. However when and where Pom1 inhibits Cdr2 is not clear as medial Pom1 levels do not change during cell elongation. Here I show that Pom1 gradients are susceptible to environmental changes in glucose. Specifically, upon glucose limitation, Pom1 re-localizes from the poles to the cell sides where it delays mitosis through regulating Cdr2. This re-localization occurs due to microtubule de- stabilization and lateral catastrophes leading to transient deposition of the Pom1 gradient nucleator Tea4 along the cell cortex. As Tea4 localization to cell sides is sufficient to recruit Pom1, this explains the mechanism of Pom1 re-localization. Microtubule destabilization and consequently Tea4 and Pom1 spread depends on the activity of the cAMP-dependent Protein Kinase A (PKA/Pka1), as pka1 mutant cells have stable microtubules and retain polar Tea4 and Pom1 under limited glucose. PKA signaling negatively regulates the microtubule rescue factor CLASP/Cls1, thus reducing its ability to stabilize microtubules. Thus PKA signaling tunes CLASP activity to promote microtubule de-stabilization and Pom1 re-localization upon glucose limitation. I show that the side-localized Pom1 delays mitosis and balances the role of the mitosis promoting, mitogen-associated protein kinase (MAPK) protein Sty1. Thus Pom1 re-localization may serve to buffer cell size upon glucose limitation. -- Afin de maintenir une taille constante, les cellules régulent leur croissance ainsi que leur taux de division selon les nutriments disponibles dans le milieu. Dans la levure fissipare, cette régulation de la taille précède l'engagement mitotique et se fait à la transition entre les phases G2 à M du cycle cellulaire. Des études récentes se sont focalisées sur le rôle de la protéine Pom1, membre de la famille des DYRK kinase. Celle-ci forme un gradient provenant des pôles de la cellule et inhibe l'activateur mitotique Cdr2 présent au centre de la cellule. Le model propose que Pom1 inhibe Cdr2 jusqu'à atteindre une taille critique avant la division. Cependant quand et à quel endroit dans la cellulle Pom1 inhibe Cdr2 n'était pas clair car les niveaux médians de Pom1 ne changent pas au cours de la l'élongation des cellules. Dans cette étude, je montre que les gradients de Pom1 sont sensibles aux changements environnementaux du taux de glucose. Plus spécifiquement, en conditions limitantes de glucose, Pom1 se relocalise des pôles de la cellule pour se distribuer sur les côtés de celle-ci. Par conséquent, un délai d'entrée en mitose est observé dû à l'inhibition Cdr2 par Pom1. Cette délocalisation est due à la déstabilisation des microtubules qui va conduire à une déposition transitoire de Tea4, le nucléateur du gradient de Pom1, tout au long du cortex de la cellule. Comme la localisation de Tea4 sur les côtés de la cellule est suffisante pour recruter la protéine Pom1, ceci explique le mécanisme de relocalisation de celle-ci. La déstabilisation des microtubules et par conséquent la diffusion de Tea4 et Pom1 dépendent de l'activité de la protéine kinase A dépendante de l'AMP cyclique (PKA/Pka1). En absence de pka1, la stabilité des microtubules n'est pas affectée ce qui permet la rétention de Tea4 et Pom1 aux pôles de la cellule même en conditions limitantes de glucose. La signalisation via PKA régule négativement le facteur de sauvetage des microtubules CLASP/Cls1 et permet donc de réduire sa fonction de déstabilisation des microtubules. Ainsi la signalisation via PKA affine l'activité des CLASP pour promouvoir la déstabilisation des microtubules et la relocalisation de Pom1 en conditions limitantes de glucose. Je montre que la localisation sur les côtés retarde l'entrée en mitose et compense l'action de la protéine Sty1, connue pour être une MAPK qui induit l'entrée en mitose. Ainsi, la relocalisation de Pom1 pourrait servir à tamponner la taille de la cellule en condition limitantes de glucose. -- Various cell types in the environment such as bacterial, plant or animal cells have a distinct cellular size. Maintaining a constant cell size is important for fitness in unicellular organisms and for diverse functions in multicellular organisms. Cells regulate their size by coordinating their growth rate to their division rate. This coupling is important otherwise cells would get progressively smaller or larger after each successive cell cycle. In their natural environment cells may face fluctuations in the available nutrient supply. Thus cells have to coordinate their division rate to the variable growth rates shown under different nutrient conditions. During my PhD, I worked with a single-celled rod shaped yeast called the fission yeast. These cells are longer when the nutrient supply is abundant and shorter when the nutrient supply is scarce. A protein that senses changes in the external carbon source (glucose) is called Protein Kinase A (PKA). The rod shape of fission yeast cells is maintained thanks to a structural backbone called the cytoskeleton. One of the components of this backbone is called microtubules, which are small tube like structures spanning the length of the cell. They transport a protein called Tea4, which in turn is important for the proper localization of another protein Pom1 to the cell ends. Pom1 helps to maintain proper shape and size of these rod shaped yeast cells. My thesis work showed that upon reduction in the external nutrient (glucose) levels, microtubules become less stable and show an alteration in their organization. A significant percentage of the microtubules contact the side of the cell instead of touching only the cell tip. This leads to the spreading of the protein Pom1 away from the tips all around the cell periphery. This helps fission yeast cells to maintain the proper size required under these conditions of limited glucose supply. I further showed that the protein PKA regulates microtubule stability and organization and thus Pom1 spreading and maintenance of proper cell size. Thus my work led to the discovery of a novel pathway by which fission yeast cells maintain their size under limited supply of glucose. -- Divers types cellulaires dans l'environnement tels que les bactéries, les plantes ou les cellules animales ont une taille précise. Le maintien d'une taille cellulaire constante est importante pour le fitness des organismes unicellulaire ainsi que pour multiples fonctions dans les organismes multicellulaires. Les cellules régulent leur taille en coordonnant le taux de croissance avec le taux de division. Ce couplage est essentiel sinon les cellules deviendraient progressivement plus petites ou plus grandes après chaque cycle cellulaire. Dans leur habitat naturels les cellules peuvent faire face a des fluctuations dans le taux de nutriment disponible. Les cellules doivent donc coordonner leur taux de division aux taux variables de croissances perçus dans les différentes conditions nutritionnels. Pendant ma thèse, j'ai travaillée sur une levure unicellulaire, en forme de bâtonnet, nommé levure fissipare ou levure de fission. La taille de ces cellules est plus grande quand le taux de nutriments est grand et plus courte quand celui-ci est plus faible. Une protéine qui perçoit les changements dans le taux externe de la source de carbone (glucose) est nommée PKA pour protéine kinase A. La forme en bâtonnet de la cellule est due aux caractères structuraux du cytosquelette. Une composante importante de ce cytosquelette sont les microtubules, dont la structures ressemble à des petit tubes qui vont d'un bout à l'autre de la cellule. Ces microtubules transportent une protéine importante nommée Tea4 qui à leur tour importante pour la bonne localisation d'une autre protéine Pom1 aux extrémités de la cellule. La protéine Pom1 aide à maintenir la taille appropriée des levures fissipares. Mon travail de thèse a montré qu'en présence de taux faible de nutriments (glucose) les microtubules deviennent de moins en moins stables et montrent une désorganisation globale. Un pourcentage significatif des microtubules touche les côtés de la cellule aux lieu d'atteindre uniquement les extrémités. Ceci a pour conséquence une diffusion de Pom1 tout au long du cortex de la cellule. Ceci aide les levures fissipares à maintenir la taille appropriée pendant ce stress nutritionnel. De plus, je montre que PKA régule la stabilité et l'organisation des microtubules et par conséquent la diffusion de Pom1 et le maintien d'une taille constante. En conclusion, mon travail a conduit à la découverte d'un nouveau mécanisme par lequel la levure fissipare maintient sa taille dans des conditions limitantes en glucose.