997 resultados para Inter-element spacing
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CREB is a cAMP-responsive nuclear DNA-binding protein that binds to cAMP response elements and stimulates gene transcription upon activation of the cAMP signalling pathway. The protein consists of an amino-terminal transcriptional transactivation domain and a carboxyl-terminal DNA-binding domain (bZIP domain) comprised of a basic region and a leucine zipper involved in DNA recognition and dimerization, respectively. Recently, we discovered a testis-specific transcript of CREB that contains an alternatively spliced exon encoding multiple stop codons. CREB encoded by this transcript is a truncated protein lacking the bZIP domain. We postulated that the antigen detected by CREB antiserum in the cytoplasm of germinal cells is the truncated CREB that must also lack its nuclear translocation signal (NTS). To test this hypothesis we prepared multiple expression plasmids encoding carboxyl-terminal deletions of CREB and transiently expressed them in COS-1 cells. By Western immunoblot analysis as well as immunocytochemistry of transfected cells, we show that CREB proteins truncated to amino acid 286 or shorter are sequestered in the cytoplasm, whereas a CREB of 295 amino acids is translocated into the nucleus. Chimeric CREBs containing a heterologous NTS fused to the first 248 or 261 amino acids of CREB are able to drive the translocation of the protein into the nucleus. Thus, the nine amino acids in the basic region involved in DNA recognition between positions 287 and 295 (RRKKKEYVK) of CREB contain the NTS. Further, mutation of the lysine at position 290 in CREB to an asparagine diminishes nuclear translocation of the protein.(ABSTRACT TRUNCATED AT 250 WORDS)
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O objetivo deste trabalho foi avaliar o desempenho de normas de sistema integrado de diagnose e recomendação (DRIS) regionais e inter-regionais no diagnóstico nutricional de café Conilon (Coffea canephora). Dados foliares de N, P, K, Ca e Mg, referentes a 268 lavouras cafeeiras do Espírito Santo e de Rondônia, foram utilizados para a definição de quatro conjuntos de normas DRIS: três para condições específicas (normas regionais) e um para todas as condições testadas (normas inter-regionais). As lavouras apresentavam grandes diferenças quanto ao manejo e às condições ambientais. Após o estabelecimento das normas, os diagnósticos nutricionais obtidos a partir delas foram confrontados entre si. Todas as normas foram efetivas em proporcionar diagnósticos que distinguissem padrões nutricionais das lavouras, tanto no Espirito Santo como em Rondônia. Na norma DRIS inter-regional, as médias e os desvios-padrão das relações multivariadas entre os nutrientes apresentaram valores intermediários, em comparação aos obtidos nos conjuntos de normas regionais. Não foi constatada aleatoriedade no diagnóstico nutricional com uso das normas inter-regionais, o qual apresentou elevado grau de concordância com o das normas regionais. Normas específicas somente devem ser utilizadas nas condições em que foram geradas, enquanto normas genéricas apresentam aplicabilidade mais ampla sem prejuízo à acurácia dos diagnósticos.
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The semi-structured diagnostic interview for genetic studies (DIGS) was developed to assess major mood and psychotic disorders and their spectrum manifestations in genetic studies. Our research group developed a French version of the DIGS and tested its inter-rater and test-retest reliability in psychiatric patients. In this article, we present estimates of the reliability of substance use and antisocial personality disorders. High kappa coefficients for inter-rater reliability were found for drug and alcohol as well as antisocial personality diagnoses and slightly lower kappas for test-retest reliability. Combined with evidence of the reliability of major mood and psychotic disorders, these findings support the suitability of the DIGS for studies of familial aggregation and comorbidity of psychiatric disorders including substance use and antisocial personality disorders.
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The U-Pb ages and the trace element content of zircon U-Pb along with major and trace element whole rock data on gabbroic dikes from the Lanzo lherzolitic massif, N-Italy, have been determined to constrain crustal accretion in ocean-continent transition zones. Three Fe-Ti gabbros were dated from the central and the southern part of the massif providing middle Jurassic ages of 161 +/- 2, 158 +/- 2 and 163 +/- 1 Ma, which argue for magmatic activity over few millions of years. Zircon crystals are characterized by high but variable Th/U ratios, rare earth element patterns enriched in heavy rare earths, pronounced positive Ce and negative Eu-anomalies consistent with crystallization after substantial plagioclase fractionation. The zircon trace element composition coupled with whole rock chemistry was used to reconstruct the crystallization history of the gabbros. A number of gabbros crystallized in situ, and zircon precipitated from trapped, intercumulus liquid, while other gabbros represent residual liquids that were extracted from a cumulus pile and crystallized along syn-magmatic shear zones. We propose a model in which the emplacement mechanism of gabbroic rocks in ocean-continent transition zones evolves from in situ crystallization to stratified crystallization with efficient extraction of residual liquid along syn-magmatic shear zones. Such an evolution of the crystallization history is probably related to the thermal evolution of the underlying mantle lithosphere.
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Electrical deep brain stimulation (DBS) is an efficient method to treat movement disorders. Many models of DBS, based mostly on finite elements, have recently been proposed to better understand the interaction between the electrical stimulation and the brain tissues. In monopolar DBS, clinically widely used, the implanted pulse generator (IPG) is used as reference electrode (RE). In this paper, the influence of the RE model of monopolar DBS is investigated. For that purpose, a finite element model of the full electric loop including the head, the neck and the superior chest is used. Head, neck and superior chest are made of simple structures such as parallelepipeds and cylinders. The tissues surrounding the electrode are accurately modelled from data provided by the diffusion tensor magnetic resonance imaging (DT-MRI). Three different configurations of RE are compared with a commonly used model of reduced size. The electrical impedance seen by the DBS system and the potential distribution are computed for each model. Moreover, axons are modelled to compute the area of tissue activated by stimulation. Results show that these indicators are influenced by the surface and position of the RE. The use of a RE model corresponding to the implanted device rather than the usually simplified model leads to an increase of the system impedance (+48%) and a reduction of the area of activated tissue (-15%).
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cAMP response element binding protein-2 (CREB-2) is a basic leucine zipper (bZIP) factor that was originally described as a repressor of CRE-dependent transcription but that can also act as a transcriptional activator. Moreover, CREB-2 is able to function in association with the viral Tax protein as an activator of the human T-cell leukemia virus type I (HTLV-I) promoter. Here we show that CREB-2 is able to interact with C/EBP-homologous protein (CHOP), a bZIP transcription factor known to inhibit CAAT/enhancer-dependent transcription. Cotransfection of CHOP with CREB-2 results in decreased activation driven by the cellular CRE motif or the HTLV-I proximal Tax-responsive element, confirming that CREB-2 and CHOP can interact with each other in vivo.
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Yritysten välinen yhteistyö kasvaa asiantuntijamarkkinoilla. Suppean palvelutarjooman omaavat yritykset muodostavat laajempia palveluita yhdistämällä osaamisiaan kumppaneidensa kanssa. Näin muodostuvat yritysryhmittymät uhkaavat alaa hallitsevia monipuolisen palvelutarjooman omaavia kansainvälisiä moniosaajayrityksiä. Tämän diplomityön tavoitteena on selvittää minkälaisia hyötyjä moniosaajayritys voi saada näitä ryhmittymiä vastaan lisäämällä omaa yhteistyötään. Tavoitteeseen pääsemiseksi markkinoilla olevat yritysryhmittymät tunnistetaan ja selvitetään minkälaisia asioita asiakas pitää tärkeänä ostaessaan asiantuntijapalveluita. Toimialan trendit ja aikaisemmat tutkimukset yritysten välisestä yhteistyöstä sekä asiakkaan ostokäyttäytymisestä osoittavat, että yhteistyön avulla yrityksellä on mahdollisuus saavuttaa monia hyötyjä. Tietoa olemassa olevista yritysryhmittymistä ja asiakkaiden ostokäyttäytymisestä kerättiin haastattelemalla yhden kansainvälisen moniosaajayrityksen henkilöstöä sekä asiakkaita. Tuloksena löytyi yritysryhmittymiä, joista osa uhkaa moniosaajayrityksen kilpailuetua. Asiakkaiden ostokäyttäyminen suosi hieman enemmän asiantuntijapalveluiden hankkimista yritysryhmittymältä moniosaajayrityksen sijaan. Tekemällä yhteistyötä ja tarjoamalla tiettyjä palveluita yhdessä kumppanin kanssa, moniosaajayritys voi saavuttaa hyötyjä yritysryhmittymiä vastaan ja vaikuttaa positiivisesti asiakkaan ostokäyttäytymiseen.
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In Arabidopsis (Arabidopsis thaliana), the blue light photoreceptor phototropins (phot1 and phot2) fine-tune the photosynthetic status of the plant by controlling several important adaptive processes in response to environmental light variations. These processes include stem and petiole phototropism (leaf positioning), leaf flattening, stomatal opening, and chloroplast movements. The PHYTOCHROME KINASE SUBSTRATE (PKS) protein family comprises four members in Arabidopsis (PKS1-PKS4). PKS1 is a novel phot1 signaling element during phototropism, as it interacts with phot1 and the important signaling element NONPHOTOTROPIC HYPOCOTYL3 (NPH3) and is required for normal phot1-mediated phototropism. In this study, we have analyzed more globally the role of three PKS members (PKS1, PKS2, and PKS4). Systematic analysis of mutants reveals that PKS2 (and to a lesser extent PKS1) act in the same subset of phototropin-controlled responses as NPH3, namely leaf flattening and positioning. PKS1, PKS2, and NPH3 coimmunoprecipitate with both phot1-green fluorescent protein and phot2-green fluorescent protein in leaf extracts. Genetic experiments position PKS2 within phot1 and phot2 pathways controlling leaf positioning and leaf flattening, respectively. NPH3 can act in both phot1 and phot2 pathways, and synergistic interactions observed between pks2 and nph3 mutants suggest complementary roles of PKS2 and NPH3 during phototropin signaling. Finally, several observations further suggest that PKS2 may regulate leaf flattening and positioning by controlling auxin homeostasis. Together with previous findings, our results indicate that the PKS proteins represent an important family of phototropin signaling proteins.
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OBJECTIVES: This study investigated the relationship between inter-arm coordination and the energy cost of locomotion in front crawl and breaststroke and explored swimmers' flexibility in adapting their motor organization away from their preferred movement pattern. DESIGN: Nine front-crawlers performed three 300-m in front crawl and 8 breaststrokers performed three 200-m in breaststroke at constant submaximal intensity and with 5-min rests. Each trial was performed randomly in a different coordination pattern: freely chosen, 'maximal glide' and 'minimal glide'. Two underwater cameras videotaped frontal and side views to analyze speed, stroke rate, stroke length and inter-limb coordination. METHODS: In front crawl, inter-arm coordination was quantified by the index of coordination (IdC) and the leg beat kicks were counted. In breaststroke, four time gaps quantified the arm to leg coordination (i.e., time between leg and arm propulsions; time between beginning, 90° flexion and end of arm and leg recoveries). The energy cost of locomotion was calculated from gas exchanges and blood lactate concentration. RESULTS: In both front crawl and breaststroke, the freely chosen coordination corresponded to glide pattern and showed the lowest energy cost (12.8 and 17.1Jkg(-1)m(-1), respectively). Both front-crawlers and breaststrokers were able to reach 'maximal glide' condition (respectively, +35% and +28%) but not 'minimal glide' condition for front crawl. CONCLUSIONS: The freely chosen pattern appeared more economic because more trained. When coordination was constrained, the swimmers had higher coordination flexibility in breaststroke than in front crawl, suggesting that breaststroke coordination was easier to regulate by changing glide time.
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The integrative and conjugative element ICEclc is a mobile genetic element in Pseudomonas knackmussii B13, and an experimental model for a widely distributed group of elements in Proteobacteria. ICEclc is transferred from specialized transfer competent cells, which arise at a frequency of 3-5% in a population at stationary phase. Very little is known about the different factors that control the transfer frequency of this ICE family. Here we report the discovery of a three-gene operon encoded by ICEclc, which exerts global control on transfer initiation. The operon consists of three consecutive regulatory genes, encoding a TetR-type repressor MfsR, a MarR-type regulator and a LysR-type activator TciR. We show that MfsR autoregulates expression of the operon, whereas TciR is a global activator of ICEclc gene expression, but no clear role was yet found for MarR. Deletion of mfsR increases expression of tciR and marR, causing the proportion of transfer competent cells to reach almost 100% and transfer frequencies to approach 1 per donor. mfsR deletion also caused a two orders of magnitude loss in population viability, individual cell growth arrest and loss of ICEclc. This indicates that autoregulation is an important feature maintaining ICE transfer but avoiding fitness loss. Bioinformatic analysis showed that the mfsR-marR-tciR operon is unique for ICEclc and a few highly related ICE, whereas tciR orthologues occur more widely in a large variety of suspected ICE among Proteobacteria.
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Référence bibliographique : Toledano, Marieschi, 35d
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Tiedosta on tullut määräävä tekijä yrityksensuorituskyvylle. Yritykset hankkivat aktiivisesti uutta tietoa ulkoisesta ympäristöstään ja tallentavat sitä tietokantoihinsa. Uusi tieto on innovaatioiden ja uusien ideoiden peruselementti. Uudet ideat pitää myös kaupallistaa, jotta niiden avulla voidaan hankkia kilpailuetua. Absorptiivisen kapasiteetin malli yhdistää tiedon prosessointiin liittyvät kyvykkyydet, jotka vaikuttavat yrityksen kykyyn hyödyntää tietoa tehokkaasti. Ennen kuin tietoa voidaan käyttää uusien tuotteiden ja palveluiden luomiseen, täytyy sitä jakaa yrityksessä ja muuttaa se yrityksen toimintaa palvelevaksi. Aiemmissa tutkimuksissa innovaatiot ovat vahvasti liitetty yrityksen kykyyn uudistua. Tämä pro gradu -tutkielma tutkii sosiaalisten integraatiomekanismien vaikutusta potentiaalisen absorptiivisen kapasiteetin muuttamiseen toteutuneeksi absorptiiviseksi kapasiteetiksi. Yksilöiden ja osastojen välisen yhteistyön sekä luottamuksen vaikutus tiedon sisäistämiseen tutkittiin. Tutkielma pohjautuu monikansallisessa yrityksessä keväällä 2006 suoritettuun uudistumiskyky-tutkimukseen. Tutkielma keskittyy yrityksen kykyyn uudistua uuden tiedon ja innovaatioiden avulla. Tutkielma on kvantitatiivinen tapaustutkimus. Tutkielmassa tehtyjen havaintojen mukaan sosiaaliset integraatiomekanismit ovat tärkeitä uuden tiedon hyödyntämisessä. Tiedon eksplisiittyyden havaitaan vaikuttavan tiedon muuttamiseen yritykselle hyödylliseksi resurssiksi.