Universidade Federal de Lavras (UFLA)
  • Lavras, Minas Gerais, Brazil
Recent publications
Resumo: A pecuária leiteira familiar é relevante para a agropecuária nacional que, embora contribua com a geração de riqueza e renda, enfrenta baixas eficiência, produtividade e custos de produção elevados. Objetivou-se analisar a eficiência técnica de propriedades leiteiras familiares no Estado de Minas Gerais. Utilizou-se a Análise por Envoltória de Dados (DEA) com modelo BCC orientado a inputs. Quanto maior foi o nível de eficiência das DMU’s, menos recursos foram utilizados em excesso. Foi identificada, ainda, a inexistência de DMU’s que realizaram manutenção preventiva de máquinas, implementos e benfeitorias, justificando o aumento da utilização, principalmente, do insumo MIB (manutenção de máquinas, implementos e benfeitorias). Com esta pesquisa, sugeriu-se o Índice de Comprometimento de Insumos em Leite (ICIL), que evidencia o percentual da produção que está comprometida para comprar um determinado insumo. Quanto maior foi o nível de eficiência das DMU’s, menor foi o ICIL, que passou de 49,36% (eficientes) para 67,47% (com eficiência baixa). Este se mostrou um importante indicador de eficiência de propriedades leiteiras, responsável por evidenciar a quantidade de leite produzido que está comprometida com o pagamento dos insumos utilizados na atividade leiteira. Também se mostrou valioso instrumento a ser utilizado como benchmark em propriedades leiteiras.
The cryopreservation of plant germplasm at ultralow temperatures is an alternative technique for the long-term storage of seeds of the genus Coffea sp. However, for this technique to be successful, cell integrity must be maintained at all stages of the process on the basis of scientific research. The present study investigated validated cryopreservation protocols for Coffea arabica L. seeds and evaluate the effects on the physiological and biochemical characteristics of the seeds at each stage of the process. Seeds were dried on silica gel or with saturated saline solution, precooled or not in a biofreezer, immersed in nitrogen, and reheated in a water bath. After each of these steps, the physiological and biochemical quality of the seeds was determined. Pre-cooling is a step that can be dispensed with in the cryopreservation of Coffea arabica seeds, direct immersion in liquid nitrogen being more indicated. Coffea arabica L. seeds tolerate cryopreservation after rapid drying in silica gel up to water contents of 17 or 20% (wb), with greater survival at 17%. The enzyme activities of catalase, polyphenol oxidase and peroxidase are indicators of the quality of C. arabica L. seeds subjected to cryopreservation.
Product sensory description is a fundamental action in sensory science, traditionally achieved through descriptive sensory tests. Rapid methods (Sorting and check all that apply [CATA]) that do not require trained sensory panels have been increasingly implemented to save time and costs. Considering the traditionality of the CATA method, this study is an extension of previous research on sensory drivers of liking of dulce de leche, comprising an investigation of Preference Sorting (PS) versus CATA to compare the results and information obtained from both techniques. PS and CATA tests showed similar results in determining dulce de leche sensory drivers of liking. However, some differences on sensory description were noted. Consumers considered the PS test more difficult than CATA. PS proved to be an alternative in determining the product sensory drivers of liking for a screening of a large number of samples, providing similar results to the traditional test—the CATA test. Practical Applications The findings of this study show practical utility for consumer‐based methodologies, focusing on sorting tasks and sensory drivers of liking determination, complementing the preference sorting studies in a comparative perspective with a traditional sensory method to understand the technique and its applicability better. In addition, they are useful for Brazilian dulce de leche producers as they enable an understanding of consumer preferences to plan production, marketing, and commercialization strategies.
The objective of this study was to evaluate the wood chemical and energetic characteristics of Eucalyptus spp. clones planted in three sites in the Midwest of Brazil. Thus, five clones from Eucalyptus spp. were planted in different sites aiming to determine the qualitative characteristics of the wood resulting from the variation in the tree growth environment and the genetic material. The same clones was planted in the three sites to determine the genotype x environment interaction. The trees were then sampled at five years after planting for their physical-chemical and energetic characterization. The results showed that the wood characteristics vary in different proportions according to the clone, just as the growth environment of the trees alters the behavior of the clones for the same characteristics. The edaphic variables affected the wood characteristics, inferring that the water content in the soil has more effect on the wood properties than the water content in the air, mainly on wood basic density. The results of this study indicate that using the appropriate genotype related to the environment conditions determines the wood characteristics, since the wood properties are strongly influenced by the edaphoclimatic variables.
The cave environment is one of the most threatened habitats in the face of mineral exploration and urban development, even though it is classified as a Brazilian cultural, biological and geological heritage. More and more on the margins of the impacts of human activities, today Brazilian caves are under high pressure for licensing, including those classified as of maximum relevance, hitherto prevented from being impacted. The diversification of ecological and conservation studies expanded to other groups, such as herpetofauna, can bring new insights into subterranean environments and increasingly consolidate the paths for the recognition of their ecological importance.
Tadarida brasiliensis, the Brazilian free-tailed bat, is an insectivorous molossid with a wide distribution in the Americas. It occurs in different ecosystems and uses varied shelters, from caves and crevices to human constructions, such as roofs and ceilings. Despite its wide distribution, there are several sampling gaps that make it difficult to identify the regions where the species occurs. This is a particular problem for the sub-species T. brasiliensis brasiliensis in South America, a region with few studies in comparison to North America. Considering these problems involved with identifying the distribution of T. b. brasiliensis in South America, we inferred its distribution based on 121 confirmed occurrences for the subspecies. We created a species distribution model (SDM) using the ensemble approach from the combination of BIOCLIM, SVM, GLM and MaxEnt algorithms. The resulting model suggested that the subspecies is unlikely to occur in the Amazon region and has a positive affinity with human population density, topography, a lower vegetation index, and the precipitation in the driest month. Our results show there is a large continuous area suitable for T. b. brasiliensis in central and eastern South America, with interruptions and narrow areas toward Central America. The population in this last area is separated from a smaller site in Chile by Andean deserts, snowy peaks, and high-altitude points. Our results demonstrated that along its distribution suitable habitat for T. b. brasiliensis is not continuous. The discontinuities in populations require further investigation to determine if there are phylogeographic consequences for the species.
This article aims to understand how the language of law mediates the relations between the lifeword and system, theoretically supporting social management by considering society as the leading actor of public actions. Social management is considered a manifestation of a non-state public interest in the complex relationships between state, market and society, whose language of law socializes and integrates, make organizations and institutions Interact and affects individuals’ public and private autonomy. To solve problems related to the tension between the lifeword and the systems, Habermas detailed his political theory along with the law, linking republicanism and liberalism, public and private autonomy, facticity, and validity. The transformations that understanding law undergo in Habermas’ work: Theory of communicative action and Law and democracy stand out. In the tensions that threaten solidarity and understanding and result in the colonization in the lifeworld by functional subsystems, the law moves from the first condition of juridicalization of social relations to the mediating position between the life world and system of converting communicative power into administrative power. Social management is an expression of the tension and mediation between the lifeworld and the system is also expression. of the tension between facticity and validity of the law, between public autonomy, and between liberalism and republicanism.
Campomanesia rufa (O. Berg) Nied. is a Myrtaceae species native to the Brazilian Cerrado. As C. rufa is considered endangered, in vitro propagation is an alternative for its conservation. However, the lack of effective disinfection protocols for endophytic microorganisms naturally present in plant tissues hinders the success of micropropagation. In this context, the objective of this study was to isolate, molecular identify, and control endogenous occurring bacteria of C. rufa propagated in vitro. Purified PCR products of bacterial isolates were sequenced by the Sanger method and aligned with homologous sequences using the Basic Local Alignment Search Tool (BLAST) available in National Centre for Biotechnology Information (NCBI) database. MEGA7 software was used to align all sequences and to draw phylogenetic trees. Survival, shoot height, and efficiency of antibiotics (streptomycin, ampicillin, and chloramphenicol) at different concentrations in the culture medium were evaluated. Different Bacillus sp. strains were observed in the plant tissues. When testing the control of Bacillus sp. with antibiotics, 32 mg L⁻¹ ampicillin caused a significant reduction in bacterial contamination with no effect on explant survival. On the other hand, 256 mg L⁻¹ streptomycin caused the greatest reduction in contamination but was lethal to over 90% of the explants. This study is the first report on the occurrence of endogenous bacteria and their control in the context of in vitro native species conservation. Index terms: ‘Casaqueira’; phylogenetic tree; Bacillus sp.; antibiotics
Resumo O objetivo deste trabalho é compreender como a linguagem do direito mediatiza as relações entre mundo-da-vida e sistema, fundamentando teoricamente a gestão social ao colocar a sociedade como protagonista das ações públicas. Consideramos, nesse aspecto, a gestão social como manifestação de um interesse público não-estatal no âmbito das relações complexas entre Estado, Mercado e Sociedade, cuja linguagem do direito socializa e integra, faz interagir organizações, instituições e afeta a autonomia pública e privada dos indivíduos. Para solucionar os problemas relativos à tensão entre mundo-da-vida e sistema, Habermas dedicou-se a detalhar sua teoria política juntamente com o direito, articulando republicanismo e liberalismo, autonomia pública e privada, facticidade e validade. O emprego do conceito de gestão social, em sua vertente habermasiana, suscita questões relativas ao direito, as quais receberam pouca atenção dos teóricos, apesar da centralidade que assumiram nas obras do autor. Destacam-se as transformações que a compreensão do direito sofre nas seguintes obras de Habermas: Teoria do agir comunicativo e Direito e democracia. As tensões que ameaçam a solidariedade e o entendimento e que resultam na colonização do mundo-da-vida pelos subsistemas funcionais, o direito transita da condição primeira de juridicialização das relações sociais para a posição mediadora entre o mundo-da-vida e o sistema, de conversão do poder comunicativo em poder administrativo. A gestão social como expressão da tensão e mediação entre mundo-da-vida e sistema é também expressão da tensão entre facticidade e validade do direito, entre autonomia pública e autonomia privada, entre liberalismo e republicanismo.
In the vast Neotropic seasonal environment, the most diverse family of bats, the Phyllostomidae (leaf-nosed bats), includes up to 93 species. As the quality and quantity of food resources fluctuate in the habitats, diet heterogeneity is observed among bat species and regions of the Neotropics. In this study, we investigated by faecal analyses, how the dietary niche (DN) of eight Phyllostomidae bat species (Artibeus planirostris, A. fimbriatus, Carollia brevicauda, C. perspicillata, Chiroderma villosum, Glossophaga soricina, Platyrrhinus lineatus, and Sturnira lilium) that occur in a karstic area in the Midwest region of Minas Gerais, Brazil, change in response to seasonal food availability. We recorded the consumption of insects and nine plant families. Moraceae was the most frequent, followed by Piperaceae. Given that seasonal dietary changes can be subtle and hardly noticeable along with fluctuating habitat conditions, we performed the DN decomposition of the eight bats species into subniches, by analysing the data with the WitOMI, which is a decomposition of the niche into temporal subniches. By improving the accuracy and details of the results, we assessed the effects of abiotic (precipitation and environmental temperature) and biotic (quantity and quality of food resources) interactions within the phyllostomid bat community. For each species, we compared niche breadth and overlap and found higher values for the dry season among morphologically similar species. The results of our study suggest that ecologically similar bat species coexist occupying different DNs.
Potential variables for the reproductive success of beef cows were evaluated. Included in the model were the age of the cow at calving; the interval between the Julian calving date and the end of the breeding season; the body weight and conditions at calving, at 75 days post-partum and at the end of the breeding season; and the mean daily variation in weight between these dates. Logistic regression was used in the analysis, with the parameters evaluated using the odds ratio statistic, estimating the chance of pregnancy. The mean rate of pregnancy was 84% and 55% for early and late-weaned cows, respectively. For early weaned cows, the regression variables were the Julian calving date, age of the cow, weight gain from calving to 75 days post-partum, and from 75 days post-partum to the end of the reproductive period. For late-weaned cows, there were only two regression variables, weight at calving and weight gain from calving to the end of the reproductive period. For every year above the average age of the herd, early weaned cows have an 80.9% greater chance of pregnancy, while a reduction of one year reduces the chance of pregnancy by 44.7%. In early weaned cows, every seven days after the mean Julian calving date reduces the chances of pregnancy by 22.6%, whereas every seven days before the mean calving date increases pregnancy by 29.2%. Greater gains in cow body weight, from calving to the end of the reproductive period, determine a greater probability of pregnancy.
Grapevine downy mildew, caused by the fungus Plasmopara viticola is a disease with a great economic impact on grapevine in the Brazil. The objective of this study was to evaluate resistance to downy mildew in seedless grapevine hybrids and one susceptible cultivar ‘Thompson Seedles’ using natural infection (cross-contamination) and artificial inoculation method under greenhouse conditions. The experiments were performed at Embrapa Semiarid, Petrolina, Pernambuco, Brazil. The first used natural infection from plants with diseased vines, and the second artificial infection in which plants were sprayed with a spore suspension with a concentration of 105 conidia mL−1. The evaluated variables were final incidence, final severity, area under the curve of disease incidence progression and area under the curve of disease severity progression. All evaluated genotypes showed symptoms of downy mildew. The CPATSA 28.14 genotype presented the lowest values of final severity, final incidence, area under the disease severity progress curve and area under the disease incidence progress curve in both experiments. Therefore, the CPATSA 28.14 genotype was identified as having greater resistance to grapevine downy mildew. Clustering by the unweighted pair grouping method using arithmetic averages (UPGMA) resulted in the separation of the genotypes into three and two similarity groups in Experiments I and II, respectively, indicating low diversity among the grapevine hybrids evaluated.
The objective of this study was to assess the impact of incorporating vermiculite into germination tests for both chemically treated and untreated stored cotton seeds. To that end, two independent experiments were conducted using cotton seeds of the cultivar DP1746B2RF under chemical treatment with a mixture of fungicide, insecticides, and nematicide; and both experiments were set up in a completely randomized design with four replications. In Experiment 1, the objective was to determine the ideal water volume for moistening the vermiculite. Four water volumes were used: 1.5, 2.0, 2.5, and 3.0 times the weight of the dry vermiculite. Experiment 2 was conducted in a 2 × 2 × 2 triple factorial arrangement consisting of two substrates (germitest paper and germitest paper + vermiculite), two treatments (chemically treated seeds and untreated seeds), and two storage periods (0 and 150 days). First germination count and germination were evaluated in the two experiments. From the results found in Experiment 1, the water volume corresponding to 3.0 times the weight of the vermiculite provided the best conditions for germination. In Experiment 2, the most appropriate substrate for conducting the germination test of untreated and chemically treated cotton seeds is vermiculite, which led to rapid germination and uniform seedling development.
Lead is a potentially toxic chemical element, being responsible for many deleterious effects in living organisms. Therefore, understanding its dynamics and influence on plant growth is relevant for food security. The influence of Pb doses on nutrient accumulation in sorghum and soybean in two tropical soils with different buffering capacities was tested in a greenhouse study with four independent experiments (one per species/soil combination). The hypothesis was that the presence of Pb in soil decreases the accumulation of nutrients in soybean and sorghum plants. Soybean cultivated in a Typic Hapludox (TH) and sorghum, cultivated in both a Rhodic Acrudox (RA) and a TH, received 0, 200, 400, 800, 1200, 1600, 2200, and 2800 mg/kg of Pb, while soybean cultivated in RA received 0, 200, 400, 800, and 1600 mg/kg of Pb. Seeds were sown 24 h after application of Pb. Plants were harvested 21 days after the emergence of at least 50% of plants from the control treatment (approximately 30 days in total). Lead, macro, and micronutrient contents were determined in the shoot dry matter (SDM), and bioavailable Pb in soil was assessed by Mehlich-1. In general, TH allowed greater Pb uptake by plants, due to its lower buffering capacity. Soybean was the most affected crop with decreasing concentrations of N, K, Mg, and Ca, the latter was especially affected, with deficiency symptoms being observed. Effects on a longer time-scale are unknown, since significant decreases in nutrient contents were observed.
Objective we aim to understand Instagram's sociotechnical role in the modest fashion market in Brazil, proposing a theoretical-empirical model to analyze this social media as a market-thinking infrastructure. Theoretical framework the research is based on market-thinking infrastructure studies recently incorporated into the marketing area. Method in this research, two techniques were used for data collection: (a) semi-structured and in-depth interviews with 27 agents of the modest fashion market and (b) non-participant observation on Instagram. Results the results demonstrate that Instagram offers an infrastructure that mediates and standardizes interactions between market actors, allowing the construction of the modest fashion market, once seen as stigmatized. Instagram's infrastructure establishes rules that will dictate users' (market actors) success (or exercised power) in the network and, consequently, in the market. Although it is impossible to carry out monetary transactions through Instagram in Brazil, it offers various material devices that encourage economic exchanges. Conclusions this study contributes to the market-thinking infrastructures literature by showing how the standardization designed to "neutralize the network's power of agency" in users' actions ends up having the opposite effect, (re)affirming its political and symbolic elements. Instagram can be considered a democratic space if its users understand and apply its neoliberals rules. Keywords: market-thinking infrastructures; market devices; market construction; social media
Eremanthus erythropappus , a species of economic importance for α-bisabolol production, has great potential for genetic improvement. However, limited knowledge on genetic parameters during the exploitation of commercial plantations hampers its progress. In this study, we estimated genetic parameters and correlations for silvicultural traits in a provenance and progenies test of E. erythropappus at 11 years of age, aiming to identify promising provenances and families. The experiment, conducted in Baependi, involved five provenances and 116 half-sib families in a complete randomized block design. Height (H), diameter at breast height (DBH), survival (SOB), and volume (Vol) were measured, and the REML/BLUP mixed model approach was used to estimate genetic parameters. Our results revealed significant genotype-level effects for all traits, except H at the provenance level. Narrow sense heritability ranged from 0.05 (SOB) to 0.17 (DBH), suggesting a substantial influence of environmental factors. Genotypic variation surpassed that of provenances, and positive phenotypic and genotypic correlations between growth traits were observed, ranging from moderate to strong. Notably, the provenances Itabirito and Delfim Moreira exhibited outstanding performance in terms of DBH and Vol. Furthermore, families 4, 6, 37, 118, and 124 emerged as top contenders for H, DBH, and Vol. Despite low heritability, selection strategies within and between provenances and families for silvicultural traits are viable. Importantly, high phenotypic and genotypic correlations allow for indirect selection, thus streamlining assessment efforts. These findings advance our understanding of genetic parameters providing valuable insights for the genetic improvement of E. erythropappus , fostering its sustainable utilization in various industries.
Plant loss occasionally occurs in field experiments with coffee crops in experimental plots. In breeding programs, such loss can be harmful, especially when the corresponding statistical analyses are not consistent with the experimentally generated data. Herein, we analyzed productivity data to determine whether the compensatory effect occurs in coffee crops, evaluated the need to correct experimental failures, and identified the best stand correction method. We used productivity data from six harvests of eleven experiments with Coffea arabica plants. The experiments were implemented in a randomized block design, with four replications and six plants per plot. The following stand correction methods were evaluated: rule of three; Zuber; Vencovsky and Cruz covariance of the average or ideal stands; and Cruz, and the data were compared without correction adjustments. The most adequate correction methods were selected based on genetic variance, selective accuracy, and progeny ordering. The compensatory effect was evident from the analyzed data, with stand correction being evidenced as beneficial in progeny competition experiments. The best results were obtained for the covariance methods using average or ideal stands, followed by the method proposed by Cruz. The rule of three and Zuber method exhibited unsatisfactory results and are not recommended for stand correction in progeny competition experiments with coffee crops.
We previously demonstrated that a 50% caloric restriction from birth improves several cardiometabolic risk factors in young rats. In this study, we investigated in middle-aged rats the consequences of a 50% caloric restriction (CR) from birth on cardiometabolic risk factors, heart function/morphology, ventricular arrhythmia, and fibrillation incidence, and cardiac intracellular proteins involved with redox status and cell survival. From birth to the age of 18 months, rats were divided into an Ad Libitum group (AL18), which had free access to food, and a CR18 group, which had food limited to 50% of that consumed by the AL18. Resting metabolic rate, blood pressure, and heart rate were recorded, and oral glucose and intraperitoneal insulin tolerance tests were performed. Blood was collected for biochemical analyses, and visceral fat and liver were harvested and weighed. Hearts were harvested for cardiac function, histological, redox status, and western blot analyses. The 50% CR from birth potentially reduced several cardiometabolic risk factors in 18-month-old rats. Moreover, compared with AL18, the CR18 group showed a ~50% increase in cardiac contractility and relaxation, nearly 3-5 times less incidence of ventricular arrhythmia and fibrillation,~18% lower cardiomyocyte diameter, and ~60% lower cardiac fibrosis. CR18 hearts also improved biomarkers of antioxidant defense and cell survival. Collectively, these results reveal several metabolic and cardiac anti-aging effects of a 50% CR from birth in middle-aged rats.
It is known that emulsifiers can modify the crystallization behavior of fats, improving their stability. In this sense, changes in the crystallization behavior of cocoa butter (CB) may contribute to reducing oil migration through its crystalline structure. This study analyzed the effect of adding sucrose stearate (S‐370) and sucrose behenate (B‐370) emulsifiers at different concentrations on oil migration in CB. The compatibility diagram curves indicated a miscible phase behavior between CB and the emulsifiers S‐370 and B‐370 at concentrations of 0.1%, 0.3%, and 0.5%, confirming the compatibility between its components. There is a significant difference (p≤0.05) for the melting point of mixtures containing 0.3% and 0.5% of S‐370, yet we can consider that all samples reach their total melting at 35°C. However, the samples containing S‐370 showed a higher firmness profile than those containing B‐370, corroborating the results of compatibility and melting point. CB exhibited characteristic two‐step isothermal crystallization at 17.5°C, with distinct effects of the emulsifiers for each crystallization step. S‐370 and B‐370 modify the solids dissolution process and oil migrating through cocoa butter. The physical properties of CB were altered by adding S‐370 and B‐370. The oil migration process differed for each emulsifier, although diffusion, the identified migration mechanism, is the same for both.
O esgoto contém grande diversidade de microrganismos, incluindo patógenos como os vírus, sendo, portanto, um meio propício para identificação da circulação de doenças infectocontagiosas – técnica conhecida como wastewater-based epidemiology (WBE). A WBE se mostra uma poderosa ferramenta de saúde pública para rastrear e sinalizar a situação epidemiológica da população, visto que as partículas virais do SARS-CoV-2 podem ser expelidas nas fezes e urina dos contaminados antes mesmo do surgimento de sintomas e do diagnóstico clínico de COVID-19. Este estudo apresenta uma revisão de literatura sobre a presença de SARS-CoV-2 e outros vírus no esgoto doméstico e as possibilidades de remoção em estações de tratamento de esgoto (ETEs) convencionais e avançadas, bem como as técnicas de concentração e detecção em amostras ambientais. Ao final do artigo, foi apresentada uma análise econômica da aplicabilidade da WBE como instrumento de predição epidemiológica da COVID-19 em um município brasileiro.
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Antonio Chalfun-Junior
  • Departamento de Biologia
Roberto Braga
  • Automatica Departament
Vania Helena Techio
  • Departamento de Biologia
Sandro Silva
  • Departamento de Educação Física
Filippe Elias de Freitas Soares
  • Departamento de Química
Epamig Câmpus Universitário, P.O.BOX: 176, 37200-000, Lavras, Minas Gerais, Brazil
Head of institution
Empresa de Pesquisa Agropecuaria de Minas Gerais
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