999 resultados para Rhythmic part
Resumo:
We have shown previously that a fetal sheep liver extract (FSLE) containing significant quantities of fetal ovine gamma globin chain (Hbgamma) and LPS injected into aged (>20 months) mice could reverse the altered polarization (increased IL-4 and IL-10 with decreased IL-2 and IFNgamma) in cytokine production seen from ConA stimulated lymphoid cells of those mice. The mechanism(s) behind this change in cytokine production were not previously investigated. We report below that aged mice show a >60% decline in numbers and suppressive function of both CD4(+)CD25(+)Foxp3(+) Treg and so-called Tr3 (CD4(+)TGFbeta(+)), and that their number/function is restored to levels seen in control (8-week-old) mice by FSLE. In addition, on a per cell basis, CD4(+)CD25(-)Treg from aged mice were >4-fold more effective in suppression of proliferation and IL-2 production from ConA-activated lymphoid cells of a pool of CD4(+)CD25(-)T cells from 8-week-old mice than similar cells from young animals, and this suppression by CD25(-)T cells was also ameliorated following FSLE treatment. Infusion of anti-TGFbeta and anti-IL-10 antibodies in vivo altered Treg development following FSLE treatment, and attenuated FSLE-induced alterations in cytokine production profiles.
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During the last two decades there has been an increase in using dynamic tariffs for billing household electricity consumption. This has questioned the suitability of traditional pricing schemes, such as two-part tariffs, since they contribute to create marked peak and offpeak demands. The aim of this paper is to assess if two-part tariffs are an efficient pricing scheme using Spanish household electricity microdata. An ordered probit model with instrumental variables on the determinants of power level choice and non-paramentric spline regressions on the electricity price distribution will allow us to distinguish between the tariff structure choice and the simultaneous demand decisions. We conclude that electricity consumption and dwellings’ and individuals’ characteristics are key determinants of the fixed charge paid by Spanish households Finally, the results point to the inefficiency of the two-part tariff as those consumers who consume more electricity pay a lower price than the others.
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Life on earth is subject to the repeated change between day and night periods. All organisms that undergo these alterations have to anticipate consequently the adaptation of their physiology and possess an endogenous periodicity of about 24 hours called circadian rhythm from the Latin circa (about) and diem (day). At the molecular level, virtually all cells of an organism possess a molecular clock which drives rhythmic gene expression and output functions. Besides altered rhythmicity in constant conditions, impaired clock function causes pathophysiological conditions such as diabetes or hypertension. These data unveil a part of the mechanisms underlying the well-described epidemiology of shift work and highlight the function of clock-driven regulatory mechanisms. The post-translational modification of proteins by the ubiquitin polypeptide is a central mechanism to regulate their stability and activity and is capital for clock function. Similarly to the majority of biological processes, it is reversible. Deubiquitylation is carried out by a wide variety of about ninety deubiquitylating enzymes and their function remains poorly understood, especially in vivo. This class of proteolytic enzymes is parted into five families including the Ubiquitin-Specific Proteases (USP), which is the most important with about sixty members. Among them, the Ubiquitin-Specific Protease 2 (Usp2) gene encodes two protein isoforms, USP2-45 and USP2-69. The first is ubiquitously expressed under the control of the circadian clock and displays all features of core clock genes or its closest outputs effectors. Additionally, Usp2-45 was also found to be induced by the mineralocorticoid hormone aldosterone and thought to participate in Na+ reabsorption and blood pressure regulation by Epithelial Na+ Channel ENaC in the kidneys. During my thesis, I aimed to characterize the role of Usp2 in vivo with respect to these two areas, by taking advantage of a total constitutive knockout mouse model. In the first project I aimed to validate the role of USP2-45 in Na+ homeostasis and blood pressure regulation by the kidneys. I found no significant alterations of diurnal Na+ homeostasis and blood pressure in these mice, indicating that Usp2 does not play a substantial role in this process. In urine analyses, we found that our Usp2-KO mice are actually hypercalciuric. In a second project, I aimed to understand the causes of this phenotype. I found that the observed hypercalciuria results essentially from intestinal hyperabsorption. These data reveal a new role for Usp2 as an output effector of the circadian clock in dietary Ca2+ metabolism in the intestine.
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The level of information provided by ink evidence to the criminal and civil justice system is limited. The limitations arise from the weakness of the interpretative framework currently used, as proposed in the ASTM 1422-05 and 1789-04 on ink analysis. It is proposed to use the likelihood ratio from the Bayes theorem to interpret ink evidence. Unfortunately, when considering the analytical practices, as defined in the ASTM standards on ink analysis, it appears that current ink analytical practices do not allow for the level of reproducibility and accuracy required by a probabilistic framework. Such framework relies on the evaluation of the statistics of the ink characteristics using an ink reference database and the objective measurement of similarities between ink samples. A complete research programme was designed to (a) develop a standard methodology for analysing ink samples in a more reproducible way, (b) comparing automatically and objectively ink samples and (c) evaluate the proposed methodology in a forensic context. This report focuses on the first of the three stages. A calibration process, based on a standard dye ladder, is proposed to improve the reproducibility of ink analysis by HPTLC, when these inks are analysed at different times and/or by different examiners. The impact of this process on the variability between the repetitive analyses of ink samples in various conditions is studied. The results show significant improvements in the reproducibility of ink analysis compared to traditional calibration methods.
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The endodermis acts as a "second skin" in plant roots by providing the cellular control necessary for the selective entry of water and solutes into the vascular system. To enable such control, Casparian strips span the cell wall of adjacent endodermal cells to form a tight junction that blocks extracellular diffusion across the endodermis. This junction is composed of lignin that is polymerized by oxidative coupling of monolignols through the action of a NADPH oxidase and peroxidases. Casparian strip domain proteins (CASPs) correctly position this biosynthetic machinery by forming a protein scaffold in the plasma membrane at the site where the Casparian strip forms. Here, we show that the dirigent-domain containing protein, enhanced suberin1 (ESB1), is part of this machinery, playing an essential role in the correct formation of Casparian strips. ESB1 is localized to Casparian strips in a CASP-dependent manner, and in the absence of ESB1, disordered and defective Casparian strips are formed. In addition, loss of ESB1 disrupts the localization of the CASP1 protein at the casparian strip domain, suggesting a reciprocal requirement for both ESB1 and CASPs in forming the casparian strip domain.
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Most anticancer drugs are characterised by a steep dose-response relationship and narrow therapeutic window. Inter-individual pharmacokinetic (PK) variability is often substantial. The most relevant PK parameter for cytotoxic drugs is the area under the plasma concentration versus time curve (AUC). Thus it is somewhat surprising that therapeutic drug monitoring (TDM) is still uncommon for the majority of agents. Goals of the review were to assess the rationale for more widely used TDM of cytotoxics in oncology. There are several reasons why TDM has never been fully implemented into daily oncology practice. These include difficulties in establishing appropriate concentration target ranges, common use of combination chemotherapies for many tumour types, analytical challenges with prodrugs, intracellular compounds, the paucity of published data from pharmacological trials and 'Day1=Day21' administration schedules. There are some specific situations for which these limitations are overcome, including high dose methotrexate, 5-fluorouracil infusion, mitotane and some high dose chemotherapy regimens. TDM in paediatric oncology represents an important challenge. Established TDM approaches includes the widely used anticancer agents carboplatin, busulfan and methotrexate, with 13-cis-retinoic acid also recently of interest. Considerable effort should be made to better define concentration-effect relationships and to utilise tools such as population PK/PD models and comparative randomised trials of classic dosing versus pharmacokinetically guided adaptive dosing. There is an important heterogeneity among clinical practices and a strong need to promote TDM guidelines among the oncological community.
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Despite a common disorder population-based data on gastro-esophageal reflux disease (GERD) in Bangladesh is lacking. This epidemiological study was designed to determine the prevalence of GERD and its association with lifestyle factors. This population-based cross-sectional study was done by door to door interview of randomly selected persons in both urban and rural areas of North Eastern part of Bangladesh by using a validated questionnaire. A cutoff point 3 was chosen as a valid and reliable scale to confirm GERD. Statistical analysis was done by SPSS-12 version and the level of significance was set at P < or = 0.05. A total of 2000 persons with an age range of 15 to 85 years were interviewed; 1000 subjects from urban area and 1000 from rural area. Among the study subjects 1064 were male and 936 were female. A total of 110 persons (5.5%) were found to have GERD symptoms and among them 47 were men and 67 were women. The monthly, weekly and daily prevalence of heart-burn and or acid regurgitation was 5.5%, 5.25% and 2.5% respectively. Female sex, increased age and lower level of education were significantly associated with GERD symptoms. Prevalence was found more among city dwellers (approximately 6.0% versus 4.8%), married (6.23%, n = 86), widowed/widowers (16.83%, n = 17) and day labourer (8.78%). Level of education inversely influenced the prevalence. No significant association of GERD was found with body mass index (BMI) and smoking. Prevalence of GERD in North-Eastern part of Bangladesh was lower than that of western world. Prevalence was found higher in urban population, women, married, widowed/widowers and in poor an dilliterate persons. BMI and smoking had no significant association with GERD.
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This paper is the first to examine the implications of switching to PT work for women's subsequent earnings trajectories, distinguishing by their type of contract: permanent or fixedterm. Using a rich longitudinal Spanish data set from Social Security records of over 76,000 prime-aged women strongly attached to the Spanish labor market, we find that PT work aggravates the segmentation of the labor market insofar there is a PT pay penalty and this penalty is larger and more persistent in the case of women with fixed-term contracts. The paper discusses problems arising in empirical estimation (including a problem not discussed in the literature up to now: the differential measurement error of the LHS variable by PT status), and how to address them. It concludes with policy implications relevant for Continental Europe and its dual structure of employment protection.
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In this paper we construct a data set on EU cohesion aid to Spain during the planning period 2000-06. The data are disaggregated by region, year and function and attempt to approximate the timing of actual executed expenditure on assisted projects.
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El projecte Aula Matemàtica consta de dues parts. 1. Elaborar un material d'autoaprenentatge en suport digital que cobreixi tots els temes de Matemàtiques de 1r. curs de les carreres de Ciències (Biologia, Química, etc.) i les Enginyeries. Aquest material, accessible des de qualsevol ordinador connectat a Internet, és una base de dades de problemes que els alumnes poden utilitzar per a treballar el temes explicats a classe, o be per cobrir deficiències a la seva formació pre-universitària. Al mateix temps, es poden realitzar exàmens, i els alumnes poden practicar amb els problemes d'examen. 2. Durant unes hores cada dia, oferir una (o diverses) aules d'informàtica al campus de la UAB amb presència de personal de suport (professors, o becaris de darrers cursos de matemàtiques o doctorat) per tal que els alumnes que vulguin (o necessitin) puguin practicar amb ajuda, i consultat els dubtes que tinguin. En la fase actual del projecte s’han fet les següents actuacions: 1. S’ha obert una aula d’informàtica amb suport de becaris a la facultat de Ciències, on a més de practicar els alumnes, s’han efectuat exàmens. 2. S’ha treballat en el programa per tal de fer-lo més amigable. 3. S’ha ampliat la base de problemes fins a 1450, i cobrir totes les assignatures de Matemàtiques i Estadística de 1r. curs de la facultat de Ciències i l’Escola Tècnica Superior d’Enginyeries. 4. S’ha començat a treballar per a la utilització del programa a Secundària. 5. S’han fet avanços molt importants per tal d’incorporar problemes amb resposta oberta. 6. El programa és accessible des de qualsevol ordenador amb Internet.
Resumo:
Aquest projecte és continuació dels projectes "Aula Matemàtica, un projecte per a la millora de l'aprenentatge de les Matemàtiques a la UAB", primera i segona part, Ref 2003MQD 00030 i Ref 2006MQD00072, els quals han permès identificar els problemes i oferir als estudiants de primer curs d'algunes titulacions pilot de Ciències de la UAB una plataforma d'autoaprenentatge que han valorat positivament. Es tracta d'una base de dades de problemes de resposta tancada, accessible per internet, que permet als estudiants practicar pel seu compte, autoevaluar-se i també al seu professor posar-los-hi un examen i controlar el temps de pràctica dels estudiants. L'aprenentatge de les Matemàtiques requereix l'automatització de certes tècniques de caire, per exemple, manipulatiu, per a l'adquisició de la qual és imprescindible un treball repetitiu d'entrenament de l'estudiant. Es tracta de proporcionar material interactiu que permeti aquest entrenament, al ritme de l’estudiant, de manera autònoma, no presencial i atractiva per a les noves generacions; però alhora oferir suport presencial quan sigui necessari. L'enorme diversificació observada en la formació inicial dels estudiants, amb la convivència de diferents vies de batxillerat en moltes titulacions de ciències, provoca una dificultat d'adaptació de les assignatures de primer curs. Es requereix per tant una major tutorització dels estudiants i oferta d'eines i material complementari per al treball individual. El projecte actual té com a objectius l'elaboració de més material i la classificació d'aquest per permetre l'adaptació de la plataforma a un major nombre d'assignatures i la millora de l'accessibilitat i la gestió d'aquesta plataforma.
Resumo:
CONTEXTE: Pour diverses raisons, les adultes et en particulier les parents croient que la pratique sportive à l'adolescence est un facteur de protection contre les comportements à risque tels que la consommation de substances. Les preuves présentes à l'intérieur de la littérature ne sont toutefois pas concluantes à ce sujet. Le principal objectif de notre étude était donc de comparer la prévalence de la consommation de substances psychoactives (licites et illicites) et de substances ergogéniques et dopantes entre les jeunes de Suisse Romande pratiquant un sport et ceux n'en pratiquant pas.METHODES: À l'aide de plusieurs méthodes de recrutement, des adolescents sportifs et non sportifs âgés de 16 à 20 ans furent invités à répondre à un questionnaire anonyme en ligne sur leur consommation de substances. Les substances psychoactives étudiées furent principalement le tabac, l'alcool, et le cannabis. Le dopage a été limité à la volonté d'améliorer les performances tout en utilisant des produits interdits selon l'Agence Mondiale Antidopage (liste 2009). Plusieurs produits légaux liés à la pratique sportive ont également été étudiés. Sur une période de 10 mois, un total de 1303 questionnaires ont été complétés. De l'échantillon final pondéré, les réponses de 1247 sujets éligibles ont été analysées.RESULTATS ET CONCLUSIONS: Dans l'ensemble, l'effet protecteur d'une pratique sportive contre l'utilisation de substances psychoactives semble dépendre de la substance à l'étude.Les jeunes non-sportifs sont plus susceptibles de fumer que les sportifs, et, parmi ces derniers, ceux évoluant dans un contexte de loisir sont plus susceptibles de fumer que ceux en pratique compétitive. Au contraire, aucune différence concernant l'abus d'alcool n'a été observée entre les adolescents sportifs et non-sportifs, indiquant que la pratique sportive ne représente pas une protection contre l'abus d'alcool. Bien que les jeunes non-sportifs soient deux fois plus susceptibles d'être utilisateurs actuels de cannabis, un jeune sportif sur neuf en a néanmoins consommé dans le dernier mois.Les trois quarts des jeunes sportifs interrogés indiquent utiliser activement des produits pour améliorer leurs performances, confirmant la tendance actuellement perçue. Parmi les substances utilisées pour améliorer les performances sportives, les produits contenant de la caféine, les boissons sportives et les suppléments alimentaires sont les trois plus souvent signalés.Peu de jeunes sportifs en Suisse Romande semblent utiliser des substances bannies par l'Agence Mondiale Antidopage, le cannabis étant celui le plus fréquemment cité.Parmi les jeunes sportifs, ceux en pratique compétitive semblent plus susceptibles d'utiliser des produits pour améliorer leurs performances que ceux évoluant dans un contexte de loisir. En outre, Un lien entre les substances psychoactives et celles prises pour améliorer les performances sportives semblent exister: tous les jeunes sportifs signalant soit fumer, avoir abusé de l'alcool récemment ou consommer actuellement du cannabis ont démontré une consommation plus élevée de produits dopants. L'usage du cannabis comme un moyen d'améliorer les performances sportives semble assez fréquent chez les consommateurs récréatifs de cette substance.Les jeunes sportifs évoluant au niveau international ont montré des taux plus bas d'abus d'alcool et de cannabis.