3,949 research outputs found
Avaliação da estabilidade do oculus sul da catedral de Cantuária
Esta publicação tem por objetivos verificar a estabilidade do oculus sul do transepto da Catedral de Cantuária do Reino Unido quando sujeito ação do vento, e estudar a influência da deterioração e da grelha exterior na sua capacidade de carga. O estudo incluiu a inspeção no local, ensaios de vibração ambiental para identificação das propriedades e a análise numérica. A análise não linear estática permitiu concluir que oculus apresenta um fator de segurança igual a dez quando sujeito à ação do vento
Safety assessment of the South oculus, Canterbury catedral (UK)
The South Oculus at Canterbury Cathedral is a wrought iron space frame consisting of two layers
(Ferramenta and Grille) connected by tie bars (Pins). It is in very good condition despite its almost 850
years of history. The in situ survey of the Cathedral confirmed that the Ferramenta and the external
grille are in general in relative good condition with the exception of some local failures. On the
contrary, the pins are the most deteriorated part of the structure. Ambient vibration tests were carried
out and the modal response of the structure was identified. In order to assess the safety of the oculus
with respect to wind load, a model of the structure was built with the finite element software DIANA
and calibrated using the results of the experimental campaign. The non-linear analysis of the existing
structure resulted in a safety factor of about ten for the wind load. In addition, parametric studies have
highlighted the importance of the external grille for the structure and have provided information of the
consequences of further deterioration in terms of the load bearing capacity of the Oculus
Temperature of denture base resin under different protocols of microwave irradiation
This in vitro study evaluated the temperature of dentures after different microwave irradiation protocols. Two complete dentures (one maxillary and one mandibular denture) were irradiated separately 4 times for each of the following 5 protocols: dentures immersed in water (G1- 6 min, G2- 3 min); dentures kept dry (G3- 6 min); dentures placed in the steam sterilizer (G4- 6 min, G5- 3 min). The final temperature of the dentures was gauged in a thin and in a thick area of each denture with an infrared thermometer. All groups presented an increase in the resin base temperature. The thin areas of the dentures underwent greater heating than the thick areas. There was no significant difference (p>0.05) between the final mean temperatures of dentures immersed in water for 6 (G1) and 3 min (G2). However, the final mean temperatures recorded in G1 and G2 exceeded 71°C and were significantly higher (<0.001) than the final mean temperatures recorded in the other groups. It may be concluded that denture base resins subjected to microwave irradiation immersed in water may be exposed to deleterious temperatures.Este estudo in vitro avaliou a temperatura de próteses submetidas a diferentes protocolos de irradiação de microondas. Duas próteses totais (uma superior e outra inferior) foram irradiadas separadamente quatro vezes para cada um dos 5 protocolos que se seguem: prótese imersas em água (G1- 6 min, G2- 3 min); prótese a seco (G3-6 min); prótese no vapor (G4- 6 min, G5- 3 min). A temperatura final das próteses foi aferida em uma área fina e uma área espessa de cada prótese com um termômetro de infravermelho. Os resultados mostraram que todos os grupos sofreram aumento de temperatura. As áreas finas da prótese tiveram mais aumento da temperatura que as áreas espessas. Não houve uma diferença estatisticamente significante (p>0,05) entre a média da temperatura final das próteses imersas em água por 6 (G1) e 3 min (G2). Entretanto, a temperatura final média observada no G1 e G2 excederam 71o C e foram significativamente maiores (p<0,001) que a temperatura final média dos outros grupos. Pode-se concluir que as bases de prótese submetidas à irradiação por microondas imersas em água podem estar expostas a temperaturas deletérias.Universidade de São Paulo USP - PIBI
Proposal for the teaching of the chemical control of supragingival biofilm
The mechanical control of supragingival biofilm is accepted as one of the most important measures to treat and prevent dental caries and periodontal diseases. Nevertheless, maintaining dental surfaces biofilm-free is not an easy task. In this regard, chemical agents, mainly in the form of mouthwashes, have been studied to help overcome the difficulties involved in the mechanical control of biofilm. The aim of this paper was to discuss proposals for the teaching of supragingival chemical control (SCC) in order to improve dentists' knowledge regarding this clinical issue. Firstly, the literature regarding the efficacy of antiseptics is presented, clearly showing that chemical agents are clinically effective in the reduction of biofilm and gingival inflammation when used as adjuvant agents to mechanical control. Thus, it is suggested that the content related to SCC be included in the curricular grid of dental schools. Secondly, some essential topics are recommended to be included in the teaching of SCC as follows: skills and competencies expected of a graduate dentist regarding SCC; how to include this content in the curricular grid; teaching-learning tools and techniques to be employed; and program content
Authentic Leadership Questionnaire: invariance between samples of Brazilian and Portuguese employees
The Authentic Leadership Questionnaire (ALQ) is used to assess authentic leadership (AL). Although ALQ is often used in empirical research, cross-cultural studies with this measure are scarce. Aiming to contribute to filling this gap, this study assesses the invariance of the ALQ measure between samples of Brazilian (N = 1019) and Portuguese (N = 842) employees. A multi-group confirmatory factor analysis was performed, and the results showed the invariance of the first- and second-order factor models between the Brazilian and Portuguese samples. The results are discussed considering their cultural setting, with the study’s limitations and future research directions being pointed out
Physical exercise as a preventive procedures inflammation of aging
Ao longo do processo de envelhecimento observa-se complexa remodelagem do sistema imunitário. Estas alterações estão associadas ao desenvolvimento de patologias responsáveis por grande parte da mortalidade em população idosa. Recentemente, a prática regular de atividades físicas tem sido proposta como intervenção não-medicamentosa com amplos benefícios sobre a regulação de processos decorrentes da imunossenescênia. Neste sentido, o presente trabalho revisou e discutiu estudos que abordam a ação de mediadores pró-inflamatórios crônicos e possíveis ações do exercício físico como agente antiinflamatório. Baseado nos resultados de estudos na literatura sugere-se que, em conjunto, a interleucina-6 (IL-6) e o fator de necrose tumoral-α (TNF- α) são as principais citocinas associadas à aterosclerose, sarcopenia e déficits cognitivos. Embora os mecanismos não sejam totalmente elucidados, o exercício reduz a atividade de citocinas pró-inflamatórias e aumenta a liberação de substancias anti-inflamatórias.During the aging is observed complex remodeling of immune system. These changes are associated with the development of diseases responsible for much of the mortality in the elderly. Recently, the regular practice of exercise has been proposed as an intervention non-medication with broad benefits on regulation processes arising from Immunosenescence. In sense, this paper reviewed and discussed studies addressing the action of pro-inflammatory mediator's chronic and possible actions of physical exercise as anti-inflammatory agent. Based on the results of studies in the literature suggest that, together, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) are the main cytokines associated with atherosclerosis, sarcopenia and cognitive deficits. Though mechanisms are not fully elucidated, the Exercise reduces the activity of pro-inflammatory and increases the release of anti-inflammatory substances
Effects of sucrose reduction on the structural characteristics of sponge cake
ABSTRACTThe consumption of reduced-calorie cakes has been increasing, however this has presented challenges to be overcome concerning the formation of their structure when the sucrose is substituted by alternative sweeteners, gums or thickening agents. The present study evaluated the internal characteristics of cakes with a reduction in sucrose, and the effects of its substitution on starch gelatinisation. Starting with a pre-established formulation, the sucrose was gradually substituted by a 1.0% mixture of sucralose in a 1.5% xanthan gum solution. In the substituted cake mix, the apparent viscosity and its thermal properties were evaluated using differential scanning calorimetry (DSC). Specific volume (SV) and cell count (CC) were evaluated in the cakes. As the sucrose content decreased (52.17 to 10.00%), the specific volume (1.94 to 0.7 mL/g), cell count (36.2 to 4.0 cell/cm2) and the apparent viscosity of the batter (337.56 to 631.40 cP) were also reduced. The results showed that substituting the sucrose contributed greatly to the formation of defects in the cake structure (holes). From the data obtained, and thermograms of standard cake batters and those with a reduction in sucrose, it can be concluded that sucralose reduced the temperature of starch gelatinisation, speeding the process and causing compaction of the cake structure during baking, favouring the formation of bubbles throughout the batter
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