976 resultados para Functions of letters


Relevância:

90.00% 90.00%

Publicador:

Resumo:

This report highlights the services the IUB provided to Iowans, along with results achieved to ensure reliability, and to improve and expand utility service infrastructure in Iowa. This information is provided in accordance with the State of Iowa Accountable Government Act, Iowa Code chapter 8E. The two basic business functions of the IUB are utility regulation and compliance, and resource management. This report covers performance information for both of these areas.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

In French the adjective petit 'small, little' has a special status: it fulfills various pragmatic functions in addition to semantic meanings and it is thus highly frequent in discourse. Résumé: This study, based on the data of two children, aged 1;6 to 2;11, argues that petit and its pragmatic meanings play a specific role in the acquisition of French adjectives. In contrast to what is expected in child language, petit favours the early development of a pattern of noun phrase with prenominal attributive adjective. The emergence and distribution of petit in the children's production is examined and related to its distribution in the input, and the detailed pragmatic meanings and functions of petit are analysed. Prenominal petit emerges early as the preferred and most productive adjective. Pragmatic meanings of petit appear to be predominant in this early age and are of two main types: expressions of endearment (in noun phrases) and mitigating devices whose scope is the entire utterance. These results, as well as instances of children's pragmatic overgeneralizations, provide new evidence that at least some pragmatic meanings are prior to semantic meanings in early acquisition.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

The transcription factors TFIIB, Brf1, and Brf2 share related N-terminal zinc ribbon and core domains. TFIIB bridges RNA polymerase II (Pol II) with the promoter-bound preinitiation complex, whereas Brf1 and Brf2 are involved, as part of activities also containing TBP and Bdp1 and referred to here as Brf1-TFIIIB and Brf2-TFIIIB, in the recruitment of Pol III. Brf1-TFIIIB recruits Pol III to type 1 and 2 promoters and Brf2-TFIIIB to type 3 promoters such as the human U6 promoter. Brf1 and Brf2 both have a C-terminal extension absent in TFIIB, but their C-terminal extensions are unrelated. In yeast Brf1, the C-terminal extension interacts with the TBP/TATA box complex and contributes to the recruitment of Bdp1. Here we have tested truncated Brf2, as well as Brf2/TFIIB chimeric proteins for U6 transcription and for assembly of U6 preinitiation complexes. Our results characterize functions of various human Brf2 domains and reveal that the C-terminal domain is required for efficient association of the protein with U6 promoter-bound TBP and SNAP(c), a type 3 promoter-specific transcription factor, and for efficient recruitment of Bdp1. This in turn suggests that the C-terminal extensions in Brf1 and Brf2 are crucial to specific recruitment of Pol III over Pol II.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

X-linked hypohidrotic ectodermal dysplasia (XLHED; OMIM 305100) is a genetic disorder characterized by absence or deficient function of hair, teeth and sweat glands. Affected children may experience life-threatening high fever resulting from reduced ability to sweat. Mice with the Tabby phenotype share many symptoms with human XLHED patients because both phenotypes are caused by mutations of the syntenic ectodysplasin A gene (Eda) on the X chromosome. Two main splice variants of Eda, encoding EDA1 and EDA2, engage the tumor necrosis factor (TNF) family receptors EDAR and XEDAR, respectively. The EDA1 protein, acting through EDAR, is essential for proper formation of skin appendages; the functions of EDA2 and XEDAR are not known. EDA1 must be proteolytically processed to a soluble form to be active. Here, we show that treatment of pregnant Tabby mice with a recombinant form of EDA1, engineered to cross the placental barrier, permanently rescues the Tabby phenotype in the offspring. Notably, sweat glands can also be induced by EDA1 after birth. This is the first example of a developmental genetic defect that can be permanently corrected by short-term treatment with a recombinant protein.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Dendritic cells (DCs) are the most potent antigen-presenting cells in the human lung and are now recognized as crucial initiators of immune responses in general. They are arranged as sentinels in a dense surveillance network inside and below the epithelium of the airways and alveoli, where thet are ideally situated to sample inhaled antigen. DCs are known to play a pivotal role in maintaining the balance between tolerance and active immune response in the respiratory system. It is no surprise that the lungs became a main focus of DC-related investigations as this organ provides a large interface for interactions of inhaled antigens with the human body. During recent years there has been a constantly growing body of lung DC-related publications that draw their data from in vitro models, animal models and human studies. This review focuses on the biology and functions of different DC populations in the lung and highlights the advantages and drawbacks of different models with which to study the role of lung DCs. Furthermore, we present a number of up-to-date visualization techniques to characterize DC-related cell interactions in vitro and/or in vivo.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

In dynamic models of energy allocation, assimilated energy is allocated to reproduction, somatic growth, maintenance or storage, and the allocation pattern can change with age. The expected evolutionary outcome is an optimal allocation pattern, but this depends on the environment experienced during the evolutionary process and on the fitness costs and benefits incurred by allocating resources in different ways. Here we review existing treatments which encompass some of the possibilities as regards constant or variable environments and their predictability or unpredictability, and the ways in which production rates and mortality rates depend on body size and composition and age and on the pattern of energy allocation. The optimal policy is to allocate resources where selection pressures are highest, and simultaneous allocation to several body subsystems and reproduction can be optimal if these pressures are equal. This may explain balanced growth commonly observed during ontogeny. Growth ceases at maturity in many models; factors favouring growth after maturity include non-linear trade-offs, variable season length, and production and mortality rates both increasing (or decreasing) functions of body size. We cannot yet say whether these are sufficient to account for the many known cases of growth after maturity and not all reasonable models have yet been explored. Factors favouring storage are also reviewed.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Abstract Protein degradation is an indispensable process for cells which is often deregulated in various diseases, including malignant conditions. Depending on the specific cell type and functions of expressed proteins, this aberration may have different effects on the determination of malignant phenotypes. A discrete, inherent feature of malignant glioma is its profound invasive and migratory potential, regulated by the expression of signaling and effector proteins, many of which are also subjected to post-translational regulation by the ubiquitin-proteasome system (UPS). Here we provide an overview of this connection, focusing on important pro-invasive protein signals targeted by the UPS.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

En este trabajo se expone e ilustra un modelo teórico para entender las funciones de la identidad, así como los mecanismospsicosociales asociados a su construcción: “Modelo Evolutivo y Funcional de la Identidad Mediada” (MEBIM). La identidad, mediada narrativamente, cumple una función personal orientada a la dirección de la propia vida, así como una función sociocultural vinculada a la búsqueda de reconocimiento de los derechos de los grupos sociales a los que uno se siente apegado. Se ilustran los factores asociados a la construcción de la identidad personal (sí mismos posibles, transiciones vitales, vínculo afectivo) y sociocultural (acción-transformación e identificación simbólica) a partir de 12 historias de vida realizadas con mestizos e indígenasde la Universidad Intercultural de Chiapas (México). Se sugiere que en contextos educativos formales, como la escuela o la Universidad, se deben propiciar narrativas personales y socioculturales con el objetivo de optimizar la identidad en un mundo a la vez globalizado y plural

Relevância:

90.00% 90.00%

Publicador:

Resumo:

We present a new indicator taxa approach to the prediction of climate change effects on biodiversity at the national level in Switzerland. As indicators, we select a set of the most widely distributed species that account for 95% of geographical variation in sampled species richness of birds, butterflies, and vascular plants. Species data come from a national program designed to monitor spatial and temporal trends in species richness. We examine some opportunities and limitations in using these data. We develop ecological niche models for the species as functions of both climate and land cover variables. We project these models to the future using climate predictions that correspond to two IPCC 3rd assessment scenarios for the development of 'greenhouse' gas emissions. We find that models that are calibrated with Swiss national monitoring data perform well in 10-fold cross-validation, but can fail to capture the hot-dry end of environmental gradients that constrain some species distributions. Models for indicator species in all three higher taxa predict that climate change will result in turnover in species composition even where there is little net change in predicted species richness. Indicator species from high elevations lose most areas of suitable climate even under the relatively mild B2 scenario. We project some areas to increase in the number of species for which climate conditions are suitable early in the current century, but these areas become less suitable for a majority of species by the end of the century. Selection of indicator species based on rank prevalence results in a set of models that predict observed species richness better than a similar set of species selected based on high rank of model AUC values. An indicator species approach based on selected species that are relatively common may facilitate the use of national monitoring data for predicting climate change effects on the distribution of biodiversity.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Background: HAART has contributed to decrease the HIV-related mortality and morbidity. However, the prevalence of HIV-associated neurocognitive disorders (HAND) seems to have increased. The aim of this study was to determine the prevalence of cognitive complaint and of HAND in a cohort of aviremic HIV_patients in the South-western part of Switzerland. Design/Methods: Two hundred HIV_ patients who had (1) undetectable HIV RNA concentrations in the plasma for_3 months, (2) no history of major opportunistic infection of the CNS in the past three years, (3) no current use of IV drugs and (4) no signs of major depression according to the DSM-IV criteria, answered a questionnaire designed to elicit cognitive complaints. Cognitive functions of a subset of HIV_ patients with or without cognitive complaints were assessed using the HIV Dementia scale (HDS) and a battery of neuropsychological tests evaluating the sub-cortical functions. Cognitive impairment was defined according to the revised diagnostic criteria for HAND. Non-parametric tests were used for statistics and a Bonferroni corrected standard p level of pB0.002 was applied for multiple comparisons. Results: The prevalence of cognitive complaints was 27% (54 patients) among the 200 questioned patients. At the time of writing this abstract, cognitive functions of 50 complaining and 28 noncomplaining aviremic patients had been assessed with the HDS and the full neuropsychological battery. The prevalence of HAND producing at least mild interference in daily functioning (mild neurocognitive disorders [MND] or HIV-associated dementia [HAD]) was 44% (34/78 patients) in the group who underwent neuropsychological testing. Objective evidences of HAND were more frequent in complaining than in non-complaining patients (pB0.001). Using a ROC curve, a cut-off of 13 on the HDS was found to have a sensitivity of 74% and a specificity of 71% (p_0.001) for the diagnosis of HAND. A trend for lower CNS Penetrating-Effectiveness scores for HAART in patients with MND or HAD as compared to the others was present (1.59 0.6 vs. 1.990.6; p_0.006 [Bonferroni correction]). Conclusions/Relevance: So far, our results suggest that (1) the prevalence of HAND is high in HIV_ patients with a long-term suppression of viremia, and (2) cognitive complaints expressed by aviremic HIV_ patients should be carefully investigated as they correlate with objective evidences of cognitive decline in a neuropsychological testing. HAART with a high CNS penetrating-effectiveness may contribute to prevent HAND. Funding: Swiss HIV Cohort Study.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Background:In January 2011 Spain modified clean air legislation in force since 2006, removing all existing exceptions applicable to hospitality venues. Although this legal reform was backed by all political parties with parliamentary representation, the government's initiative was contested by the tobacco industry and its allies in the hospitality industry. One of the most voiced arguments against the reform was its potentially disruptive effect on the revenue of hospitality venues. This paper evaluates the impact of this reform on household expenditure at restaurants and bars and cafeterias. Methods and empirical strategy:We use micro-data from the Encuesta de Presupuestos Familiares (EPF) for years 2006 to 2012 to estimate "two part" models where the probability of observing a positive expenditure and, for those who spend, the expected level of expenditure are functions of an array of explanatory variables. We apply a before-after analysis with a wide range of controls for confounding factors and a flexible modeling of time effects.Results:In line with the majority of studies that analyze the effects of smoking bans using objective data, our results suggest that the reform did not cause reductions in households' expenditures on restaurant services or on bars and cafeteria services.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

An adverse endogenous environment during early life predisposes the organism to develop metabolic disorders. We evaluated the impact of intake of an iso-caloric fructose rich diet (FRD) by lactating mothers (LM) on several metabolic functions of their male offspring. On postnatal d 1, ad libitum eating, lactating Sprague-Dawley rats received either 10% F (wt/vol; FRD-LM) or tap water (controls, CTR-LM) to drink throughout lactation. Weaned male offspring were fed ad libitum a normal diet, and body weight (BW) and food intake were registered until experimentation (60 d of age). Basal circulating levels of metabolic markers were evaluated. Both iv glucose tolerance and hypothalamic leptin sensitivity tests were performed. The hypothalamus was dissected for isolation of total RNA and Western blot analysis. Retroperitoneal (RP) adipose tissue was dissected and either kept frozen for gene analysis or digested to isolate adipocytes or for histological studies. FRD rats showed increased BW and decreased hypothalamic sensitivity to exogenous leptin, enhanced food intake (between 49-60 d), and decreased hypothalamic expression of several anorexigenic signals. FRD rats developed increased insulin and leptin peripheral levels and decreased adiponectinemia; although FRD rats normally tolerated glucose excess, it was associated with enhanced insulin secretion. FRD RP adipocytes were enlarged and spontaneously released high leptin, although they were less sensitive to insulin-induced leptin release. Accordingly, RP fat leptin gene expression was high in FRD rats. Excessive fructose consumption by lactating mothers resulted in deep neuroendocrine-metabolic disorders of their male offspring, probably enhancing the susceptibility to develop overweight/obesity during adult life.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This report highlights the services the IUB provided to Iowans, along with results achieved to ensure reliability, and to improve and expand utility service infrastructure in Iowa. This information is provided in accordance with the State of Iowa Accountable Government Act, Iowa Code chapter 8E. The two basic business functions of the IUB are utility regulation and compliance, and resource management. This report covers performance information for both of these areas.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Abstract : The maintenance of genome stability is a challenge for all living organisms. DNA is regularly subjected to chemical alterations by both endogenous and exogenous DNA damaging agents. If left unrepaired, these lesions will create mutations or lead to chromosomal instability. DNA crosslinking agents probably bring about the most toxic lesions. By linking covalently the two strands of DNA, crosslinking agents will impede essential cellular processes such as replication and transcription. Cells from Fanconi anaemia patients are extremely sensitive to these agents. Fanconi anaemia (FA) is a rare chromosomal instability disorder that leads to developmental defects, pancytopenia and cancer susceptibility. FA is a genetically heterogeneous disease with thirteen complementation groups identified. Proteins encoded by the FA genes work together in the FA pathway. Eight of these proteins form the FA core complex (FANC-A, B, C,E, F, G, L and -M), whose integrity is required to monoubiquitinate FANCD2 and FANCI in response to DNA damage. The hypersensitivity of FA cells to crosslinking agents, which perturb the progression of replication forks, has led to the hypothesis that FA proteins play a crucial role in the response to replication stress. However, at the molecular level, the functions of the FA pathway remain largely unknown. Our efforts were first focused on the characterization of FANCD2, "the key effector of the FA pathway". Using different substrates, we found that in vitro, purified hFANCD2 preferentially binds single strand DNA and double strand DNA extremities. Concomitantly, FANCM was identified as a new component of the FA core complex. Moreover FANCM was shown to have specific branch migration activities and probably a role as a "landing platform" on DNA for the other components of the core complex. By using FANCM mutants carrying deletions within the internal domain, we investigated the role of FANCM as a DNA anchor protein for the core complex. We observed that indeed, a specific part of the internal domain of FANCM interacts with components of the core complex. Finally, in collaboration with Weidong Wang's lab we characterized two new components of the FA pathway: FAAP10 and FAAP16. As a heterodimer these two proteins show affinity for dsDNA, and anneal complementary oligonucleotides in vitro. Moreover these proteins can associate with FANCM via a part of its internal domain. We find that FANCM, FAAP 10 and FAAP 16 can co-exist on the branch point of replication and recombination intermediates, and that FAAP10 and FAAP16 stimulate replication fork reversal by FANCM. These results suggest that FANCM may function as a landing platform for the core complex. After loading on DNA, the core complex can activate FANCD2 through monoubiquitination leading to its recruitment to the site of damage. Since ssDNA and double strand breaks are intermediates that are generated as a consequence of collapsed replication forks, FANCD2 by binding to ds DNA ends and ssDNA could protect such structures from the recombination repair machinery and prevent unscheduled recombination events. Alternatively, FANCD2 could avoid nucleases from gaining access to collapsed forks, preserving the DNA in state that can be used as a starting point for resumption of DNA synthesis. The overall comprehension of the FA pathway is far from been complete. Our results unravel new aspects of Fanconi Anaemia, which hopefully in the near future will address keys questions leading to a better understanding of the fascinating Fanconi Anaemia. Résumé : Le maintien de l'intégrité du génome est fondamentale chez tous les organismes vivants. L'ADN est constamment altéré par des composés aussi bien endogènes qu'exogènes. Si ces altérations ne sont pas réparées, elles peuvent conduire à l'apparition de mutations, ainsi qu'à une instabilité génomique accrue. Les lésions les plus sévères qui peuvent survenir sur l'ADN, sont les pontages inter caténaires. Des agents pontants en liant de façon covalente les deux brins d'ADN, vont empêcher le déroulement normal de processus cellulaires essentiels tels que la réplication ou la transcription. La compréhension des mécanismes permettant à la cellule de tolérer et réparer ces lésions est primordiale, notamment dans le cas des patients atteints de l'anémie de Fanconi qui présentent une très grande sensibilité à ces composés pontants. L'anémie de Fanconi est une maladie génétique rare appartenant à un groupe de pathologies associées à une grande instabilité chromosomique. Les patients atteints de l'anémie de Fanconi présentent des malformations du squelette, une pancytopénie et une forte propension à la survenue de cancer. L'anémie de Fanconi est génétiquement très hétérogène. À ce jour, 13 gènes codant pour 13 protéines FANC différentes ont été identifiés. Huit de ces protéines fonctionnent ensemble au sein d'un complexe (nommé le complexe FANC) ayant pour but de monoubiquitiner FANCD2 et FANCI en réponse à la formation de lésions sur l'ADN. L'extrême sensibilité des cellules de patients atteints de l'anémie de Fanconi à ces agents pontant l'ADN suggère l'implication des protéines FANC dans la réponse cellulaire suite à une stress réplicatif. Cependant, le rôle moléculaire exact de ces protéines demeure encore inconnu. Après purification, nous avons observé que FANCD2 était capable de lier l'ADN simple brin, ainsi que les extrémités d'ADN in vitro. Dans le même temps, FANCM fut identifié comme appartenant au complexe FANC. FANCM est décrit comme une translocase capable de promouvoir le déplacement de point de jonction dans des structures d'ADN spécifiques in vitro. De plus, en se liant à l'ADN, FANCM peut agir comme une plateforme pour les autres protéines FANC, leur permettant ainsi d'être adressées à l'ADN. En créant des protéines FANCM recombinantes ayant des délétions dans le domaine interne, nous avons pu observer que certaines protéines du complexe FANC se fixent à des sites spécifiques sur le domaine interne de FANCM. Enfin, au travers d'une collaboration, nous avons été amenés à caractériser deux nouvelles protéines appartenant au complexe FANC : FAAP 10 et FAAP16. Elles s'associent à FANCM par l'intermédiaire du domaine interne, et forment ainsi un hétérotrimére. La présence de FAAP10 et FAAP16 n'affecte pas la liaison de FANCM à l'ADN, mais semble potentialiser son activité de régression in vitro. FANCM semble donc fonctionner comme une plateforme pour les autres composants du complexe FANC. Ces derniers, une fois liés à l'ADN permettent la monoubiquitination de FANCD2 et son recrutement au site lésé de l'ADN. FANCD2 en se liant de façon préférentielle à l'ADN simple brin et aux extrémités d'ADN qui sont générés lors de l'arrêt et du démantèlement d'une fourche de réplication, pourrait protéger ces même fourches de réplication arrêtées, d'évènements de recombinaison aléatoires. Nos résultats apportent de nouveaux éléments concernant les mécanismes moléculaires de l'anémie de Fanconi. Enfin, l'étude de l'anémie de Fanconi permet aussi de mieux comprendre les mécanismes mis en place par la cellule pour tolérer des lésions survenant lors de la réplication.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Bone morphogenetic proteins (Bmps) regulate the expression of the proneural gene Atoh1 and the generation of hair cells in the developing inner ear. The present work explored the role of Inhibitor of Differentiation genes (Id1-3) in this process. The results show that Id genes are expressed in the prosensory domains of the otic vesicle, along with Bmp4 and Bmp7. Those domains exhibit high levels of the phosphorylated form of Bmp-responding R-Smads (P-Smad1,5,8), and of Bmp-dependent Smad transcriptional activity as shown by the BRE-tk-EGFP reporter. Increased Bmp signaling induces the expression of Id1-3 along with the inhibition of Atoh1. Conversely, the Bmp antagonist Noggin or the Bmp-receptor inhibitor Dorsomorphin elicit opposite effects, indicating that Bmp signaling is necessary for Id expression and Atoh1 regulation in the otocyst. The forced expression of Id3 is sufficient to reduce Atoh1 expression and to prevent the expression of hair cell differentiation markers. Together, these results suggest that Ids are part of the machinery that mediates the regulation of hair cell differentiation exerted by Bmps. In agreement with that, during hair cell differentiation Bmp4 expression, P-Smad1,5,8 levels and Id expression are downregulated from hair cells. However, Ids are also downregulated from the supporting cells which contrarily to hair cells exhibit high levels of Bmp4 expression, P-Smad1,5,8, and BRE-tk-EGFP activity, suggesting that in these cells Ids escape from Bmp/Smad signaling. The differential regulation of Ids in time and space may underlie the multiple functions of Bmp signaling during sensory organ development.