Recent developments on the thermal properties, stability and applications of nanofluids in machining, solar energy and biomedicine

In this review work, the recent progress made in the use of nanofluids (NFs) applied in three specific areas will be presented: machining, solar energy, and biomedical engineering. Within this context, the discussions will be guided by emphasizing the thermal and stability properties of these fluids. In machining, NFs play a prominent role in the processes of turning, milling, drilling, and grinding, being responsible for their optimization as well as improving the useful life of the tools and reducing costs. In the solar energy field, NFs have been used in the thermal management of the panels, controlling and homogenizing the operating temperature of these systems. In the biomedical area, the advantages of using NFs come from the treatment of cancer cells, the development of vaccines before the improvement of diagnostic imaging, and many others. In all lines of research mentioned in this study, the main parameters that have limited or encouraged the use of these fluids are also identified and debated. Finally, the discussions presented in this review will inspire and guide researchers in developing new techniques to improve the applications of NFs in several fields.This research was partially funded by the Portuguese national funds of FCT/MCTES (PIDDAC) through the base funding from the following research units: UIDB/00690/2020 (CIMO), UIDB/04077/2020 (MEtRICs), and UIDB/00532/2020 (CEFT). The authors are also grateful for the funding of ANI and CIMO through the projects POCI-01-02B7-FEDER-069844 and CMFPE3- EXPL2021CIMO_01, respectively. The authors also acknowledge partial financial support from the project NORTE-01-0145-FEDER-030171 (PTDC/EMD-EMD/30171/2017), PTDC/EME-TED/7801/ 2020 and EXPL/EME-EME/0732/2021 funded by the NORTE 2020 Portugal Regional Operational Programme, under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) and by Fundação para a Ciência e Tecnologia (FCT)

GENETIC PARAMETERS AND PREDICTIVE GENETIC GAIN IN MAIZE WITH MODIFIED RECURRENT SELECTION METHOD

The modified recurrent selection method suggests a less productive population to test the other population more productive and itself aiming to have more genetic gains than tradition recurrent selection method that uses one population to test the other one. The objectives of this work were to estimate the genetic components, to predict and to evaluate the genetic gains of the SynFlint and Syndent populations of maize ( Zea mays L.), applying a modified recurrent selection method. Two recombination cycles were carried out, with 144 S1 progeny per cycle. These progenies were test crossed with SynFlint, generating a SynFlint × Syndent inter-population and a SynFlint × SynFlint intra-population. The progenies were evaluated in five environments in the first cycle of selection and in three in the second cycle of selection, in a 12 × 12 lattice. Genetic variability in plant height and ear height, ear weight and prolificacy was observed in the first cycle of selection and in plant height and ear height in the second cycle. The intensity of selection practiced in the first cycle exhausted the genetic variability in ear weight and prolificacy. It can conclude that the two maize populations evaluated do not show adequate levels of genetic variability and predicted genetics gains estimates to allow their use in breeding programs to obtain lines and superior hybrids; and the modified recurrent selection method is inefficient to increase in population performance per se for the two populations

PARENTAL COMMERCIAL MAIZE SELECTION FOR SILAGE PRODUCTION

The objectives of this study were to select maize genitors and determine the selection strategy for obtaining high quality silage maize hybrids. An experiment was conducted involving 45 hybrids obtained using a diallel scheme among commercial hybrids and four controls, in a triple lattice 7 x 7 design. The general combining ability (GCA) and specific combining ability (SCA) were significant for dry matter yield (DMY) and crude protein (CP), indicating additive and non-additive gene effects in genetic control. Only GCA was significant for plant height (PH), green matter yield (GMY) and hemicelluloses (HEM), which indicates a greater importance of additive than non-additive genetic effects in genetic control. The GCA and SCA of neutral detergent fiber (NDF) and acid detergent fiber (ADF) did not differ significantly between the hybrids, but there was a variance of 33% to 49% for NDF and 15 to 24% for ADF. The cultivars P30F90 and SHS4070 were the most recommended for increasing PH, GMY and DMY, while 2B619 and DKB466 were recommended to increase CP, and BRS3003 and AG1051 to reduce HEM. The hybrid combinations XB8028 x DKB 466, Valent x CD307, Valent x DKB466, SHS4070 x AG1051, BRS3003 x 2B619 and 2B619 x AG1051 are promising for maize silage production, because of their associated productive and qualitative traits

Controle genético da resistência aos enfezamentos do milho Genetic control of the resistance to corn stunt

O objetivo deste trabalho foi identificar o controle genético da resistência aos enfezamentos do milho (Zea mays L.). Foram realizados dois experimentos em março de 2001 nos municípios de Coimbra e Sete Lagoas, em Minas Gerias. Cada experimento foi constituído por 25 tratamentos, dos quais cinco foram representados pelos híbridos e os demais pelas combinações híbridas e suas recíprocas. Utilizou-se o delineamento em blocos ao acaso, com três repetições. A parcela experimental foi aproveitada integralmente, constituindo-se de duas linhas com 5 m de comprimento e espaçamento de 0,9 m, com 25 plantas por linha, representando uma população de aproximadamente 55.000 plantas por hectare. Na época do enchimento dos grãos realizaram-se as avaliações de incidência e severidade dos enfezamentos. Utilizou-se, ainda, o índice de doença. Nos dois locais, foram avaliadas as produções de grãos de milho em cada parcela. Em virtude de o método baseado na incidência dos sintomas apresentar alta herdabilidade, foi possível confirmar sua eficiência. Os alelos com efeitos predominantemente aditivos controlam a resistência do milho aos enfezamentos; os genitores diferiram quanto à freqüência de alelos aditivos e não-aditivos para resistência aos enfezamentos.<br>The objective of this work was to identify the genetic control of the resistance to corn (Zea mays L.) stunt. Two experiments were set up at March 2001, in Coimbra and Sete Lagoas, Minas Gerais State, Brazil. Each experiment consisted of 25 treatments, five of them were represented by maize hybrids. Other treatments were the hybrid combinations and their reciprocal ones. The randomized blocks design with three replicates was used. The experimental plot was integrally used and consisted of two 5 m rows at a 0.9 m spacing from each other, with 25 plants per row, representing a population around 55,000 plants ha-1. At the time of kernel fulfilling, the evaluations were performed for incidence and severity of the corn stunt. The disease index was also used. In both places, the productivity of the maize kernels were evaluated for each plot. Therefore, since this method presents high heritability it was possible to confirm its efficiency. The genetic control of the resistance to corn stunt is mainly controlled by the alleles with predominant addictive effects; the parents differed in relation to the frequency of the addictive and nonaddictive alleles for resistance to corn stunt

Efeito da fertilização fosfatada na produção de raízes, liteira e nodulação de Mimosa caesalpiniifolia benth Effects of phosphorus fertilization on root, litter and nodule production of Mimosa caesalpiniifolia

Este trabalho visou avaliar o efeito da adubação fosfatada sobre a nodulação, deposição de liteira e desenvolvimento do sistema radicular de M. caesalpiniifolia Benth, antes e depois da poda, na Estação Experimental de Itambé, da Instituto Agronômico de Pernambuco - IPA. Os tratamentos foram níveis de adubação fosfatada (0, 100 e 200 kg.ha-1 de P2O5), em delineamento com blocos casualizados com seis repetições no bloco I e sete no II, sendo o critério para formação de blocos a data do corte de uniformização. Amostragens foram realizadas antes e depois da poda da parte aérea. O comprimento, a massa seca radicular, a matéria seca de nódulos e a liteira tiveram resultados semelhantes antes e depois da poda. O número de nódulos antes da poda foi de 2, 15 e 6 nos níveis de 0, 100 e 200 kg.ha-1 de P2O5, respectivamente, e 1, 6 e 7 após a poda. Comprimentos radiculares médios variaram entre 552 e 734 cm antes da poda e 389 e 455 cm após. Apenas de agosto a novembro de 2005 o número de nódulos apresentou variação, sendo observados valores de 2 a 15 nódulos antes da poda e 1 a 7 depois.<br>This work aimed to evaluate the effect of phosphorus fertilization on nodulation, litter deposition and root system development of M. caesalpiniifolia Benth, before and after pruning, at the Itambé Experimental Station of Pernambuco Agronomical Institute - IPA in Pernambuco, Brazil. Treatments were levels of phosphorus fertilization (0, 100 and 200 kg.ha-1 of P2O5) arranged in a randomized block design with six replicates in block I and seven in block II, with the criterion for block formation being uniformization cut date. Samplings were taken before and after pruning of the aerial part Root length and root, nodule and litter dry matter had similar results before and after pruning. Nodule numbers before pruning were 2, 15 and 6 for 0, 100 and 200 kg.ha-1 of P2O5, respectively, and 1, 6 and 7 after pruning. Average root lengths ranged from 552 to 734 cm before and from 389 to 455 cm after pruning. The number of nodules presented variation only from August to November 2005, with values from 2 to 15 and from 1 to 7 nodules, before and after pruning, respectively