Thermal diffusion in solids : an overview

Thermal diffusion in liquids and gases has been the focus of a number of studies and is considered, at present, a reasonably wellknown topic. In solids though, the phenomena is far less understood namely in what regards the effects of thermal gradients upon the integrity and characteristics of materials. Furthermore it is not clear whether or not thermal diffusion can be used as a purificating method for solids. Yet, many current techniques such as the laser, used in metal working and other solids, induce strong thermal gradients being, therefore, potential cause for the occurrence of thermal diffusion. In this work, a survey and discussion of theoretical and experimental studies of thermal diffusion in solids is undertaken

The validity of the Hoffman and Emery equation in thermal diffusion

The most widely used equation in thermal diffusion is discussed in what concerns its range of validity. It is shown that when the separation curves are non-symmetrical with respect to the initial composition the error involved in the Hoffman and Emery equation when using a value of t=0.3 tr for the lower limit of the time, may be significantly larger than those predicted by their original authors. Experimental cases described in the literature are discussed on the light of previous analysis

Evaluation of the genetic polymorphism of Plasmodium falciparum P126 protein (SERA or SERP) and its influence on naturally acquired specific antibody responses in malaria-infected individuals living in the Brazilian Amazon

<p>Abstract</p> <p>Background</p> <p>The <it>Plasmodium falciparum </it>P126 protein is an asexual blood-stage malaria vaccine candidate antigen. Antibodies against P126 are able to inhibit parasite growth <it>in vitro</it>, and a major parasite-inhibitory epitope has been recently mapped to its 47 kDa N-terminal extremity (octamer repeat domain – OR domain). The OR domain basically consists of six octamer units, but variation in the sequence and number of repeat units may appear in different alleles. The aim of the present study was to investigate the polymorphism of P126 N-terminal region OR domain in <it>P. falciparum </it>isolates from two Brazilian malaria endemic areas and its impact on anti-OR naturally acquired antibodies.</p> <p>Methods</p> <p>The study was carried out in two villages, Candeias do Jamari (Rondonia state) and Peixoto de Azevedo (Mato Grosso state), both located in the south-western part of the Amazon region. The repetitive region of the gene encoding the P126 antigen was PCR amplified and sequenced with the di-deoxy chain termination procedure. The antibody response was evaluated by ELISA with the Nt47 synthetic peptide corresponding to the P126 OR-II domain.</p> <p>Results</p> <p>Only two types of OR fragments were identified in the studied areas, one of 175 bp (OR-I) and other of 199 bp (OR-II). A predominance of the OR-II fragment was observed in Candeias do Jamari whereas in Peixoto de Azevedo both fragments OR-I and OR-II were frequent as well as mixed infection (both fragments simultaneously) reported here for the first time. Comparing the DNA sequencing of OR-I and OR-II fragments, there was a high conservation among predicted amino acid sequences of the P126 N-terminal extremity. Data of immune response demonstrated that the OR domain is highly immunogenic in natural conditions of exposure and that the polymorphism of the OR domain does not apparently influence the specific immune response.</p> <p>Conclusion</p> <p>These findings confirm a limited genetic polymorphism of the P126 OR domain in <it>P. falciparum </it>isolates and that this limited genetic polymorphism does not seem to influence the development of a specific humoral immune response to P126 and its immunogenicity in the studied population.</p

Promoting ecosystems conservation and community-based economic alternatives in a changing climate: impacts of tourism (Cananéia, São Paulo, Brazil)

Cananéia is the southernmost city in the state of São Paulo, Brazil. It is a municipality where the tertiary sector is the main contributor to the economy parallel to the maintenance of artisanal fishing activities. The authors perform a study on the impact of tourism in the municipality area (performed through surveys in an attempt to determine how the different population segments [residents, promoters, users] see the activity and its impacts on nature and on the local economy). The majority of tourists surveyed come from the state of São Paulo (83.3%) and the rest of Santa Catarina and Paraná, with ages from 19-25 (36.7%) (70% having higher education). 43.3% of the inquired stated that tourism is not correctly managed (however without relevant environmental impacts). 93.3% of the boaters and 66.7% of the interviewed referred lack of information about the sites ecology and the drivers of change of biodiversity, ecosystem services, and climate change. Questionnaires results clearly demonstrated the need for visitor information and interpretation envisaging sustainable tourism implementation.info:eu-repo/semantics/publishedVersio

Mercury toxicity to freshwater organisms: extrapolation using species sensitivity distribution

Mercury toxicity to aquatic organisms was evaluated in different taxonomic groups showing the following species sensitivity gradient: Daphnia magna > Daphnia longispina > Pseudokirchneriella subcapitata > Chlorella vulgaris > Lemna minor > Chironomus riparius. Toxicity values ranged from 3.49 μg/L (48 h-EC₅₀ of D. magna) to 1.58 mg/L (48 h-EC₅₀ of C. riparius). A species sensitivity distribution was used to estimate hazardous mercury concentration at 5 % level (HC5) and the predicted no effect concentration (PNEC). The HC5 was 3.18 μg Hg/L and the PNEC varied between 0.636 and 3.18 μg Hg/L, suggesting no risk of acute toxicity to algae, plants, crustaceans and insects in most freshwaters.We thank João Pedrosa, Tânia Vidal and Abel Ferreira (Department of Biology of the University of Aveiro) for providing C. riparius, L. minor cultures and algae cultures, respectively. The Portuguese Foundation for Science and Technology (FCT) supported the Post-doctoral fellowship SFRH/BPD/45807/2008 and CAPES- FCT 240/09 and the doctoral fellowship SFRH/BD/ 27637/2006.publishe

Assessing university student perceptions and comprehension of climate change (Portugal, Mexico and Mozambique)

Higher education system has a critical role to play in educating environmentally aware and participant citizens about global climate change (CC). And, as shown by the 21st Conference of the Parties of the UN Convention on Climate Change – COP 21, held in Paris in December 2015, there is still a path to be followed regarding the role played by universities in the negotiations and in influencing decision-making on a matter of such global importance. The purpose of this first study conducted within Portuguese (Europe), Mexican (Spanish-speaking North America University) and Mozambican (Africa) universities is to investigate higher education system students’ perceptions on CC. Design/methodology/approach The data were collected through a questionnaire aiming at characterising students from the socio-demography, and from their perceptions, motivations, attitudes and knowledge relating to the topic of CC. Statistical analysis was used to compare and characterise the three national groups under study. Findings This study did not show significant perception differences among the analysed subsamples, although there was a tendency for Mexican students to express lesser belief that CC was happening, and for Mozambicans to show a greater belief in CC issues and motivation to mitigate its effects which may be related to the specifics contexts. The results show that relevant differences among nationalities mostly concerned the magnitude of choices (e.g. most respondents of each nationality expressed interest in CC issues, but the magnitude of this expression differed according to nationality). The principal component analysis (second and third components) clearly embodied nationality profiles (discussed in the context of different cultures, educational structures and CC impacts). Research limitations/implications Further research is warranted to understand the integration of CC into higher education curriculum to improve and target educational efforts to suit students’ needs. Practical implications How CC perceptions vary cross-nationally and how research studies that examine the integration of CC into higher education curriculum are areas for which more research is needed. Originality/value The results highlight the importance of socio-cultural dimensions of each country in relation to the understanding or perception of CC issues, namely, in what concerns aspects related with gender roles, age, active learning and citizenship. This study’s data evidenced that despite the surveyed students being familiarized with CC phenomena, this knowledge does not translate necessarily into concrete mitigation practices and behaviours.info:eu-repo/semantics/publishedVersio

Is There Any Difference between the In Situ and Systemic IL-10 and IFN-γ Production when Clinical Forms of Cutaneous Sporotrichosis Are Compared?

Submitted by Sandra Infurna ([email protected]) on 2016-12-15T11:14:37Z No. of bitstreams: 1 fernanda_morgado_etal_IOC_2016.pdf: 4768094 bytes, checksum: 5ab755cd6bdf28be44e74b4620b05950 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2016-12-15T11:30:54Z (GMT) No. of bitstreams: 1 fernanda_morgado_etal_IOC_2016.pdf: 4768094 bytes, checksum: 5ab755cd6bdf28be44e74b4620b05950 (MD5)Made available in DSpace on 2016-12-15T11:30:54Z (GMT). No. of bitstreams: 1 fernanda_morgado_etal_IOC_2016.pdf: 4768094 bytes, checksum: 5ab755cd6bdf28be44e74b4620b05950 (MD5) Previous issue date: 2016Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Imunoparasitologia. Rio de Janeiro, RJ. Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa em Leishmaniose. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz, Instituto Nacional de Infectologia Evandro Chagas. Serviço de Infectologia - VigLeish. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz, Instituto Nacional de Infectologia Evandro Chagas. Serviço de Infectologia - VigLeish. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz, Instituto Nacional de Infectologia Evandro Chagas. Serviço de Infectologia - VigLeish. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz, Instituto Nacional de Infectologia Evandro Chagas. Serviço de Infectologia - VigLeish. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz, Instituto Nacional de Infectologia Evandro Chagas. Serviço de Infectologia - VigLeish. Rio de Janeiro, RJ, Brasil / New University of Lisbon (UNL). Hygiene and Tropical Medicine Institute (IHMT). Lisboa, Portugal.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Imunoparasitologia. Rio de Janeiro, RJ. Brasil.Fungus of the Sporothrix schenckii complex can produce skin lesions in humans, commonly lymphocutaneous (LC) and fixed (F) forms of sporotrichosis. Some authors have suggested that clinical forms are influenced by differences in virulence and genetic profile of isolates. But little is known about the role of immune response in determining the clinical outcome of sporotrichosis. To verify the profile of systemic and in situ IFN-γ and IL-10 expression in sporotrichosis patients, and consequently to detect any difference between the two compartments and/or clinical presentation, we quantified the number of IFN-γ and IL-10 producer peripheral blood mononuclear cells stimulated with S. schenckii antigen (Ss-Ag) by Elispot, and quantified cytokines expression by in situ immunohistochemistry in the same patient. Three groups were formed: 1- LC (n = 9); 2- F (n = 10); 3- healthy individuals (n = 14). All sporotrichosis patients produced high amounts of systemic IFN- γ when compared to uninfected individuals. No differences were observed between LC and F groups. Regarding in situ IL-10 expression, a difference between LC and F groups was observed: LC lesions presented higher amounts of IL-10 than F lesions differently from systemic IL-10 which showed similarities. Our data suggests that LC lesions present higher IL-10 expression which could be related to regulatory mechanisms for compensating the tissue injury, however favoring fungal persistence in the lesions. Surprisingly, there were no differences in systemic and in situ IFN- γ expression between CL and F patients, although it was significantly higher expressed in these patients than in healthy individuals