Experimental Determination of the Convective Coefficient of Heat Transfer Using the Global Capacitance Method

The heat transfer coefficient (h) is an extremely important variable in the evaluation of convective heat transfer, however, its determination is a great challenge due to the various factors that influence it: fluid viscosity, fluid density, specific heat of the fluid, thermal conductivity of the fluid, coefficient of volumetric expansion, fluid velocity. The objective of this work is the experimental determination of the convective heat transfer coefficient by means of the global capacitance method. Three test bodies, two cylindrical bodies and one spherical body were used. These specimens were individually heated in a stove, and heating was monitored by means of a thermocouple and a data logger. The results showed a good concordance between the values of h obtained experimentally and the literature

Genetic diversity and population structure of Cynara cardunculus L. in southern Portugal

Cynara cardunculus L. is a cardoon species native to the Mediterranean region, which is composed of three botanical taxa, each having distinct biological characteristics. The aim of this study was to examine wild populations of C. cardunculus established in Portugal, in order to determine their genetic diversity, geographic distribution, and population structure. Based on SSR markers, 121 individuals of C. cardunculus from 17 wild populations of the Portuguese Alentejo region were identified and analysed. Ten SSRs were found to be efficient markers in the genetic diversity analysis. The total number of alleles ranged from 9 to 17 per locus. The expected and observed means in heterozygosity, by population analysed, were 0.591 and 0.577, respectively. The wild population exhibited a high level of genetic diversity at the species level. The highest proportion of genetic variation was identified within a geographic group, while variation was lower among groups. Geographic areas having highest genetic diversity were identified in Alvito, Herdade da Abo´boda, Herdade da Revilheira and Herdade de São Romão populations. Moreover, significant genetic differentiation existed between wild populations from North-Alentejo geographic locations (Arraiolos, E´ vora, Monte da Chamine´ ) and Centro Hortofrutı´cola, compared with other populations. This study reports genetic diversity among a representative number of wild populations and genotypes of C. cardunculus from Portugal. These results will provide valuable information towards future management of C. cardunculus germplasm.info:eu-repo/semantics/publishedVersio

Genetic diversity of bromeliaceae species from the atlantic forest

The Bromeliaceae family includes a range of species used for many purposes, including ornamental use and use as food, medicine, feed, and fiber. The state of Espírito Santo, Brazil is a center of diversity for this family in the Atlantic Forest. We evaluated the genetic diversity of five populations of the Bromeliaceae family, including specimens of the genera Aechmea, Billbergia (subfamily Bromelioideae), and Pitcairnia (subfamily Pitcairnioidea), all found in the Atlantic Forest and distributed in the state of Espírito Santo. The number of alleles per locus in populations ranged from two to six and the fixation index (F), estimated for some simple sequence repeats in bromeliad populations, was less than zero in all populations. All markers in the Pitcairnia flammea population were in Hardy-Weinberg equilibrium (P < 0.05). Moreover, significant deviations from Hardy-Weinberg equilibrium were observed at some loci in populations of the five bromeliad species. In most cases, this can be attributed to the presence of inbreeding or the Wahlund effect. The genetic diversity indices of five species showed greater allelic richness in P. flammea (3.55). Therefore, we provide useful information for the characterization of genetic diversity in natural populations of Aechmea ramosa, Aechmea nudicaulis, Billbergia horrid, Billbergia euphemia, and P. flammea in Atlantic Forest remnants in the south of Espírito Santo state. © 2017 The Authors