50 resultados para Reflect Array


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Sunlight exposure causes several types of injury to humans, especially on the skin; among the most common harmful effects due to ultraviolet (UV) exposure are erythema, pigmentation and lesions in DNA, which may lead to cancer. These long-term effects are minimized with the use of sunscreens, a class of cosmetic products that contains UV filters as the main component in the formulation; such molecules can absorb, reflect or diffuse UV rays, and can be used alone or as a combination to broaden the protection on different wavelengths. Currently, worldwide regulatory agencies define which ingredients and what quantities must be used in each country, and enforce companies to conduct tests that confirm the Sun Protection Factor (SPF) and the UVA (Ultraviolet A) factor. Standard SPF determination tests are currently conducted in vivo, using human subjects. In an industrial mindset, apart from economic and ethical reasons, the introduction of an in vitro method emerges as an interesting alternative by reducing risks associated to UV exposure on tests, as well as providing assertive analytical results. The present work aims to describe a novel methodology for SPF determination directly from sunscreen formulations using the previously described cosmetomics platform and mass spectrometry as the analytical methods of choice.

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Calcium dynamics is central in cardiac physiology, as the key event leading to the excitation-contraction coupling (ECC) and relaxation processes. The primary function of Ca(2+) in the heart is the control of mechanical activity developed by the myofibril contractile apparatus. This key role of Ca(2+) signaling explains the subtle and critical control of important events of ECC and relaxation, such Ca(2+) influx and SR Ca(2+) release and uptake. The multifunctional Ca(2+)-calmodulin-dependent protein kinase II (CaMKII) is a signaling molecule that regulates a diverse array of proteins involved not only in ECC and relaxation, but also in cell death, transcriptional activation of hypertrophy, inflammation and arrhythmias. CaMKII activity is triggered by an increase in intracellular Ca(2+) levels. This activity can be sustained, creating molecular memory after the decline in Ca(2+) concentration, by autophosphorylation of the enzyme, as well as by oxidation, glycosylation and nitrosylation at different sites of the regulatory domain of the kinase. CaMKII activity is enhanced in several cardiac diseases, altering the signaling pathways by which CaMKII regulates the different fundamental proteins involved in functional and transcriptional cardiac processes. Dysregulation of these pathways constitutes a central mechanism of various cardiac disease phenomena, like apoptosis and necrosis during ischemia/reperfusion injury, digitalis exposure, post-acidosis and heart failure arrhythmias, or cardiac hypertrophy. Here we summarize significant aspects of the molecular physiology of CaMKII and provide a conceptual framework for understanding the role of the CaMKII cascade on Ca(2+) regulation and dysregulation in cardiac health and disease.

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There is a growing demand for renewable energy, and sugarcane is a promising bioenergy crop. In Brazil, the largest sugarcane producer in the world, sugarcane plantations are expanding into areas where severe droughts are common. Recent evidence has highlighted the role of miRNAs in regulating drought responses in several species, including sugarcane. This review summarizes the data from miRNA expression profiles observed in a wide array of experimental conditions using different sugarcane cultivars that differ in their tolerance to drought. We uncovered a complex regulation of sugarcane miRNAs in response to drought and discussed these data with the miRNA profiles observed in other plant species. The predicted miRNA targets revealed different transcription factors, proteins involved in tolerance to oxidative stress, cell modification, as well as hormone signaling. Some of these proteins might regulate sugarcane responses to drought, such as reduction of internode growth and shoot branching and increased leaf senescence. A better understanding on the regulatory network from miRNAs and their targets under drought stress has a great potential to contribute to sugarcane improvement, either as molecular markers as well as by using biotechnological approaches.

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This article is divided into two parts. The first presents two abstract arguments that constitute the starting point for the development of the second part, which is directed towards discussing some aspects of the distance learning policies, i.e., the role of public authorities in encouraging and shaping this type of education. First of all, it is intended to establish some assumptions to understand the emergence of this phenomenon and some of its conditioning factors and consequences; then to suggest some analytical tools to allow us to reflect on public policy in this area.

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The first days of radioactivity, the discoveries of X-rays, radioactivity, of alpha- and beta- particles and gamma- radiation, of new radioactive elements, of artificial radioactivity, the neutron and positron and nuclear fission are reviewed as well as several adverse historical marks, such as the Manhattan project and some nuclear and radiological accidents. Nuclear energy generation in Brazil and the world, as an alternative to minimize environmental problems, is discussed, as are the medicinal, industrial and food applications of ionizing radiation. The text leads the reader to reflect on the subject and to consider its various aspects with scientific and technological maturity.

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How should one consider the responsibility of the translator, who is located between the differences of two linguistic systems and in the middle of the various idioms constitute each of the languages involved in the translation? (P. Ottoni). What is the role of the translator in inter-acting with both his/her mother tongue and the idiom of the other? These two questions will be discussed in order to reflect on the responsibility of translating the un-translatable. Two hypotheses orient the paper: 1 - an idiom spoken idiomatically is known as the mother tongue and is not appropriated, so that accommodating the other in one's own language automatically considers his/her idiom (J. Derrida) and 2 - face-to-face with language and its idioms, the translator is trapped in a double (responsibility) bind; faced with something which cannot be translated, he/she is forced to perceive it in another way. In conclusion, how should one consider the responsibility of translating the un-translatable Jacques Derrida?

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PURPOSE: To describe the main success attitudes of young ophthalmologists in the first decade of their career. METHODS: This descriptive study comprised subjects selected from a sample of ophthalmologists who were participating in a congress, using a semi-structured questionnaire. The inclusion criteria were as follows: ophthalmologists under the age of 40 years, within 5-10 years from ophthalmology residency conclusion. The subjects were asked about the three main success attitudes in their personal experience during the first years of ophthalmology practice. After the initial results, the 10 most frequently mentioned attitudes were listed and volunteers were again interviewed to choose, within the latter list, the three main attitudes. RESULTS: Forty-eight ophthalmologists were interviewed, 24 (50%) were male; the mean age was 37 years (SD: 2 years, range: 33-40 years) and the mean time from ophthalmology residency conclusion was 8 years (SD: 1 year, range: 5-10 years). The frequency of such mentioned success attitudes were as follows: to invest in professional updating (22.9%), to have a good relationship with patients and professional partners (18.8%), to prioritize individual and family happiness (12.5%), initially to work in an established group (11.1%), to work in public service (9.7%), to have their own business with a homogeneous group (7.6%), to save money (7.6%), to be ready to resume work (4.2%), to get business administration skills (4.2%), and to have professional insurance (0.7%). CONCLUSIONS: The three main success attitudes consisted in investing in professional updating (22.9%), maintaining a good relationship with patients and professional partners (18.8%), and prioritizing individual and family happiness (12.5%). Although these results should not be generalized, they are helpful not only for those ophthalmologists at the beginning of a career but also those who want to reflect on what to prioritize in their professional practice.

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física