914 resultados para Frame-timing
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Empirical research has shown that pubertal development is closely linked with adolescent externalizing (e.g., aggressive) and internalizing (e.g., anxiety) problems. In most studies, pubertal timing, pubertal status, or both, are used to examine this link. The present study adds to the existing literature by examining the link between puberty and adolescent behavior problems in a sample of predominantly urban African American adolescent girls. One hundred and seventeen adolescent girls of color, aged 11-18 (M = 14.72 SD = 1.44), and their primary caregiver participated in this study. Sixty-eight percent were African American, 22.2 % were Hispanic/Latina, and 9.4% were Haitian. Among the Hispanic/Latina girls, 9.4% were Black Hispanic/Latina. Results showed that pubertal status and perceived pubertal timing (breasts) are better predictors of externalizing behavior problems than chronological age and quality of relationship with peers. No significant findings were found with anxious/depressed symptoms.
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Pre-reperfusion administration of intravenous (IV) metoprolol reduces infarct size in ST-segment elevation myocardial infarction (STEMI). This study sought to determine how this cardioprotective effect is influenced by the timing of metoprolol therapy having either a long or short metoprolol bolus-to-reperfusion interval. We performed a post hoc analysis of the METOCARD-CNIC (effect of METOprolol of CARDioproteCtioN during an acute myocardial InfarCtion) trial, which randomized anterior STEMI patients to IV metoprolol or control before mechanical reperfusion. Treated patients were divided into short- and long-interval groups, split by the median time from 15 mg metoprolol bolus to reperfusion. We also performed a controlled validation study in 51 pigs subjected to 45 min ischemia/reperfusion. Pigs were allocated to IV metoprolol with a long (−25 min) or short (−5 min) pre-perfusion interval, IV metoprolol post-reperfusion (+60 min), or IV vehicle. Cardiac magnetic resonance (CMR) was performed in the acute and chronic phases in both clinical and experimental settings. For 218 patients (105 receiving IV metoprolol), the median time from 15 mg metoprolol bolus to reperfusion was 53 min. Compared with patients in the short-interval group, those with longer metoprolol exposure had smaller infarcts (22.9 g vs. 28.1 g; p = 0.06) and higher left ventricular ejection fraction (LVEF) (48.3% vs. 43.9%; p = 0.019) on day 5 CMR. These differences occurred despite total ischemic time being significantly longer in the long-interval group (214 min vs. 160 min; p < 0.001). There was no between-group difference in the time from symptom onset to metoprolol bolus. In the animal study, the long-interval group (IV metoprolol 25 min before reperfusion) had the smallest infarcts (day 7 CMR) and highest long-term LVEF (day 45 CMR). In anterior STEMI patients undergoing primary angioplasty, the sooner IV metoprolol is administered in the course of infarction, the smaller the infarct and the higher the LVEF. These hypothesis-generating clinical data are supported by a dedicated experimental large animal study.
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TESLA project (Transfering Energy Save Laid on Agroindustry) financed by the European Commission, had the main goals of evaluating the energy consumption and to identify the best available practices to improve energy efficiency in key agro-food sectors, such as the olive oil mills. A general analysis of energy consumptions allowed identifying the partition between electrical and thermal energy (approximately 50%) and the production processes responsible for the higher energy consumptions, as being the in the mill and paste preparation and the phases separation. Some measures for reducing energy waste and for improving energy efficiency were identified and the impact was evaluated by using the TESLA tool developed by Circe and available at the TESLA website.
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Two novelties are introduced: (i) a finite-strain semi-implicit integration algorithm compatible with current element technologies and (ii) the application to assumed-strain hexahedra. The Löwdin algo- rithm is adopted to obtain evolving frames applicable to finite strain anisotropy and a weighted least- squares algorithm is used to determine the mixed strain. Löwdin frames are very convenient to model anisotropic materials. Weighted least-squares circumvent the use of internal degrees-of-freedom. Het- erogeneity of element technologies introduce apparently incompatible constitutive requirements. Assumed-strain and enhanced strain elements can be either formulated in terms of the deformation gradient or the Green–Lagrange strain, many of the high-performance shell formulations are corotational and constitutive constraints (such as incompressibility, plane stress and zero normal stress in shells) also depend on specific element formulations. We propose a unified integration algorithm compatible with possibly all element technologies. To assess its validity, a least-squares based hexahedral element is implemented and tested in depth. Basic linear problems as well as 5 finite-strain examples are inspected for correctness and competitive accuracy.
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In recent decades the importance of structuring sciences such as botany or phytosociology faced a declining attention from the scientific community. This was accompanied by a growing interest in theoretical ecology. For such scenario greatly contributed an hypothetical exhaustion of research topics in these areas, but especially the introduction of new technologies that have provided powerful tools for data analysis. This allowed, for example, to make predictions about the impacts of climate change on species and plant communities and the consequent recognition of theoretical ecology, as one of the most prestigious pieces of current biological sciences. However, theoretical ecology has been facing serious knoledge gaps that greatly compromise their results, putting again the spotligth on structuring sciences. For example there are enourmous gaps in knowledge and data on dispersal, species and communities chorology and abundace, as well as in biological interactions. These data is essential, since they will determine ecological behavior of species. Its omission always limits the understanding and proper execution of the models generated by theoretical ecology. In this conference we will present a review on the gaps in knowledge and data in flora and vegetation fields in order to identify situations where geobotanical knowledge can make their major contribution. Furthermore, we will emphasize the need to reformulate objectives in geobotanical sciences in order to give it the deserved scientific recognition, considering the relationship between different scientific knowledges.
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2011
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2015
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A partire dal 1986, nell’Olanda settentrionale si sta verificando un incremento di fenomeni sismici superficiali di medio-bassa intensità. Siccome la zona è considerata a basso rischio sismico, tali fenomeni sono legati all’estrazione di gas nella regione Groningen situata a nord-est del paese, la quale rappresenta il più grande giacimento d’Europa. Di conseguenza, si sono verificati danni ingenti sulle strutture che sorgono in zona, che di fatto non erano state progettate per resistere a forze orizzontali legate all’accelerazione del suolo. Ricercatori, aziende e università sono stati coinvolti nel progetto di ricerca finalizzato alla valutazione della vulnerabilità sismica delle costruzioni esistenti, in modo da poter avviare interventi di miglioramento o adeguamento sismico. A questo scopo, presso l’università tecnica di Delft sono stati svolti diversi test sperimentali e analitici su murature non rinforzate tipiche olandesi, che rappresentano la tipologia costruttiva più diffusa e si distinguono per la presenza di maschi murari snelli, grandi aperture e inadeguatezza delle connessioni tra gli elementi strutturali. Lo scopo della tesi è verificare l’adeguatezza del modello a telaio equivalente implementato nel software 3Muri per la modellazione di due tipiche case a schiera in muratura non rinforzata. Tali case, precedentemente ricostruite e testate in laboratorio attraverso un’analisi pushover, differiscono per metodologia costruttiva ed i materiali utilizzati.
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The aim of this thesis was to quantify experimentally in the field the effects of different timing regimes of hypoxia on the structure of benthic communities in a transitional habitat. The experiment was performed from 8 July to 29 July 2019 in a shallow subtidal area in Pialassa Baiona (Italy), a lagoon characterized by mixing regimes dominated by the tide. The benthic community was isolated using cylinders 15,5Cm x 20Cm size. Hypoxic conditions were imposed by covering the treated cylinders with a black plastic bag while control cylinders were left uncovered. We created 4 different timing regimes of hypoxia by manipulating both the duration of hypoxia (4 or 8 days) as well as the ratio between the duration of subsequent periods of hypoxia and the duration of a normoxic period between subsequent hypoxic events (D4R3/2, D8R3/2). At the end of each experimental trial, the benthic communities within each pot were retrieved, sieved in the field and subsequent analyzed in the laboratory where organisms were identified and counted. Results showed that benthic organism were generally negatively affected by hypoxic stress events. As expected, longer hypoxic events caused a stronger decrease of benthic community abundance. When the hypoxic events were interrupted by the normoxic event there were two different results. If the hypoxic period was too long, the normoxic period didn’t cause a positive recovery effect, and further decline of the benthic community was observed. Conversely normoxia had positive effects if the period of hypoxia was short enough not to compromise the benthic community. This resulted in a statistically significant interaction between the tested factors Duration and Ratio. Amphipods were the most sensitive organisms to hypoxia. We conclude that the effects of hypoxia can be greatly relieved by short normoxic periods if they happen frequently enough.
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The Crescent Shaped Brace (CSB) is a new simple steel hysteretic device proposed to be used as an enhanced diagonal brace in framed structures. The CSB allows the practical designer to choose the lateral stiffness independently from the yield strength of the device, due to its peculiar ad-hoc shape. In the present thesis, a complete study referring to different CSB configurations has been presented. After the validation of the hysteretic capacities of the Crescent Shaped Braces, the seismic concept of the "enhanced first story isolation" system has been proposed within the PBSD. It relies on the total separation between the Vertical Resisting System (VRS) and the Horizontal Resisting System (HRS) in order to attain a certain objective curve of the structure. An applicative example has been studied following this concept and exploiting the advantages of the CSBs as seismic dissipative devices used for the HRS. Then several geometrical configurations called Single CSB system, Single 2 CSB system, Double CSB system, Coupled CSB system, Coupled with high length CSB system, and the final one was Cross bracing system have been introduced and modelled with SAP2000 and the results have been compared.
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Lo studio che verrà presentato in questo lavoro di tesi riguarda la caratterizzazione di Silicon PhotoMultiplier (SiPM): essi sono sensori a semiconduttore che sono stati proposti per la realizzazione del layer Time-Of-Flight (TOF) del nuovo esperimento proposto ad LHC, ALICE 3. Sono stati testati sensori diversi, sia in termini di casa di fabbricazione (FBK o HPK), sia in termini di struttura; in particolare, i modelli a disposizione di produzione FBK sono singoli SPAD, singoli SiPM e mini-array di SiPM, mentre i modelli HPK sono tutti singoli SiPM. La caratterizzazione è avvenuta mediante misure di corrente e capacità del sensore al variare della tensione (curve IV e curve CV); l'obiettivo primario è studiare e confrontare tali andamenti, in modo da poter selezionare i sensori con caratteristiche simili per la costruzione del layer del TOF. Si è osservato che sensori della stessa casa produttrice e con la stessa struttura interna esibiscono comportamenti quasi sovrapponibili, dimostrando in generale una ottima uniformità.
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Spider venoms contain neurotoxic peptides aimed at paralyzing prey or for defense against predators; that is why they represent valuable tools for studies in neuroscience field. The present study aimed at identifying the process of internalization that occurs during the increased trafficking of vesicles caused by Phoneutria nigriventer spider venom (PNV)-induced blood-brain barrier (BBB) breakdown. Herein, we found that caveolin-1α is up-regulated in the cerebellar capillaries and Purkinje neurons of PNV-administered P14 (neonate) and 8- to 10-week-old (adult) rats. The white matter and granular layers were regions where caveolin-1α showed major upregulation. The variable age played a role in this effect. Caveolin-1 is the central protein that controls caveolae formation. Caveolar-specialized cholesterol- and sphingolipid-rich membrane sub-domains are involved in endocytosis, transcytosis, mechano-sensing, synapse formation and stabilization, signal transduction, intercellular communication, apoptosis, and various signaling events, including those related to calcium handling. PNV is extremely rich in neurotoxic peptides that affect glutamate handling and interferes with ion channels physiology. We suggest that the PNV-induced BBB opening is associated with a high expression of caveolae frame-forming caveolin-1α, and therefore in the process of internalization and enhanced transcytosis. Caveolin-1α up-regulation in Purkinje neurons could be related to a way of neurons to preserve, restore, and enhance function following PNV-induced excitotoxicity. The findings disclose interesting perspectives for further molecular studies of the interaction between PNV and caveolar specialized membrane domains. It proves PNV to be excellent tool for studies of transcytosis, the most common form of BBB-enhanced permeability.
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Witches' broom disease (WBD) of cacao differs from other typical hemibiotrophic plant diseases by its unusually long biotrophic phase. Plant carbon sources have been proposed to regulate WBD developmental transitions; however, nothing is known about their availability at the plant-fungus interface, the apoplastic fluid of cacao. Data are provided supporting a role for the dynamics of soluble carbon in the apoplastic fluid in prompting the end of the biotrophic phase of infection. Carbon depletion and the consequent fungal sensing of starvation were identified as key signalling factors at the apoplast. MpNEP2, a fungal effector of host necrosis, was found to be up-regulated in an autophagic-like response to carbon starvation in vitro. In addition, the in vivo artificial manipulation of carbon availability in the apoplastic fluid considerably modulated both its expression and plant necrosis rate. Strikingly, infected cacao tissues accumulated intracellular hexoses, and showed stunted photosynthesis and the up-regulation of senescence markers immediately prior to the transition to the necrotrophic phase. These opposite findings of carbon depletion and accumulation in different host cell compartments are discussed within the frame of WBD development. A model is suggested to explain phase transition as a synergic outcome of fungal-related factors released upon sensing of extracellular carbon starvation, and an early senescence of infected tissues probably triggered by intracellular sugar accumulation.
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This work indicates presuppositions for the qualitative research in Physical Education, starting with a literature review based on the cultural frame of reference. Firstly, we introduce the debate concerning the natural and the human sciences and implications for the Physical Education; we then use a cultural axis as a ground basis for the research in the area, proposing the 'dense description' as a possibility for knowledge building; finally, we bring up examples of studies conducted with such an approach. This theoretical methodological approach allows the study of the human being as a cultural being, thus opposed to the naturalised view of a human - predominant in Physical Education.
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Universidade Estadual de Campinas . Faculdade de Educação Física