372 research outputs found
Simulação da deposição de líquido e avaliação de pontas de pulverização para aplicação de herbicidas.
Objetivou-se, com este trabalho, realizar a simulação da deposição de líquido e
avaliação de pontas de pulverização para aplicação de herbicidas. Foram realizados
quatro experimentos com o objetivo de avaliar a distribuição volumétrica e o espectro
de gotas de pontas de pulverização de baixa deriva; a distribuição de líquido da ponta de
pulverização com indução de ar e jato excêntrico AIUB 8502 sob diferentes condições;
a simulação da deposição de líquido de uma barra para aplicação de herbicidas em faixa
em áreas florestais com diferentes pontas de pulverização; e a distribuição volumétrica
de pontas de pulverização de longo alcance. Todas as análises foram realizadas nos
laboratórios do Centre de Mecanització Agrária de la Genaralitat de Catalunya no
campus Universitário da Universitat de Lleida – Espanha. No experimento 1 observou se que as pontas proporcionaram perfil descontínuo nas pressões de 300 e 400 kPa e
uniforme a 200 kPa. Ocorre menor CV (abaixo de 7%) com maior pressão de trabalho e
menor espaçamento entre pontas. À medida que se aumenta a pressão de trabalho,
reduz-se o DMV. As pontas TTI110015 e AI110015 em todas as pressões e a ponta
AVI11001, na pressão de 200 kPa, produzem gotas extremamente grossas e gotas
grossas nas pressões de 300 e 400 kPa apenas para a ponta AVI11001. As pontas
proporcionam baixos valores de amplitude relativa (A.R.) e gotas de tamanho uniforme. As pontas produzem baixa porcentagem de gotas menores que 100 µm, principalmente
as pontas TTI110015 e AI110015, com menor risco de deriva. Foi observado no
experimento 2 que a ponta AIUB 8502 apresentou distribuição de líquido excêntrica
com um lado descontínuo e extremidade oposta excêntrica, com queda abrupta do
volume de líquido. À medida que se aumentou a altura da barra e a pressão de trabalho,
alongou-se o perfil do jato. O maior número de configurações uniformes foi obtido na
altura de 50 cm decrescendo nas alturas de 40 e 30 cm. A vazão e o ângulo do jato
excêntrico aumentaram com o incremento na pressão, não havendo diferença entre o
ângulo do jato descontínuo e total entre as pressões de 400 e 500 kPa, e 200 e 300 kPa.
No experimento 3 somente foi observado perfil uniforme da barra para a ponta AIXR
nos espaçamentos de 100 e 120 cm e da ponta AIRMIX no espaçamento de 100 cm.
Todas as pontas apresentaram vazão de acordo com a norma ISSO 5682-1 de
codificação por cores. No experimento 4 foram observados que as pontas XT010 e
XP10 apresentaram perfil irregular em todas as condições avaliadas com picos de
deposição próxima a localização da ponta. A ponta XP20 apresentou perfil ligeiramente
mais uniforme, com maior deposição de líquido na faixa central e redução abrupta nas
extremidades. Foram observados CV% com valores entre 24,74 a 59,91%. A ponta
XP20 apresentou sete configurações com CV% abaixo de 40% e as pontas XT010 e
XP10 seis e duas respectivamente. O incremento na pressão e na altura promoveu
alongamento do perfil e aumento da faixa de aplicação pulverizada, com valores entre
1,95 até 5,00 m. Essas pontas apresentam potencial uso na aplicação de herbicidas que
não exigem boa cobertura e uniformidade do alvo como, os herbicidas sistêmicos
aplicados em pós-emergência e herbicidas aplicados em pré-emergência.This work had the objective to simulate the liquid deposition and spray nozzles
to herbicides application. Therefore, was conducted four experiments to evaluate: 1) the
volumetric distribution and droplet spectra by low drift spray nozzles; 2) liquid
distribution of air induction and off-center spray nozzle under different conditions; 3)
simulation of liquid deposition of a spray boom to herbicide application in tracks in
forests areas with different spray nozzles and 4) volumetric distribution of long range
eccentric spray nozzles. All tests were performed in the laboratories of the Centre de
Mecanització Agraria de la Genaralitat de Catalunya on the campus of the Universitat
de Lleida – Spain. In experiment 1 showed the nozzles provided discontinuous profile
in 300 and 400 kPa and uniform profile at 200 kPa. Satisfactory CV (under 7%)
obtained, when it was used highest pressure and lowest space between nozzles. The
droplet size (VMD) was reduced as pressure was increased. Nozzles TTI110015 and
AI11015 in all pressures and nozzle AVI11001, in 200 kPa had presented extra coarse
droplets and coarse droplets with AVI11001 under 300 and 400 kPa pressures. The
nozzles (AI and TTI) had presented more uniformity of droplet size on the highest
pressure than AVI, considering the value of span. Nozzles had presented low % 100
µm, out standing the nozzle TTI110015 and AI110015 with smaller value, therefore with smallest drift risk. Was observed in experiment 2, the nozzle AIUB 8502,
presented an eccentric distribution of liquid with a discontinuous side and eccentric
opposing end, with sharp decrease in the volume of liquid. Increases in the height of the
bar and the working pressure extended up the profile distribution. The largest number of
uniform configurations was obtained in the height of 50 cm, decreasing in the heights of
40 and 30 cm. The angle and flow rate of the off-center nozzle increased with the
increase in pressure, with no differences between discontinuous and total angles
between 400 and 500 kPa, and 200 and 300 kPa pressure ranges. Experiment 3 was only
observed uniform profile of the bar with the nozzle AIXR space in 100 and 120 cm and
the nozzle AIRMIX spaced in 100 cm. All nozzles presented flow rate according to ISO
5682-1 color-coding. In experiment 4 it is observed irregular profile in all conditions to
the nozzles XT010 and XP10 with peaks of deposition near to the tip location. The
nozzle profile XP20 has slightly more uniform, with greater deposition of liquid in the
central belt and abrupt reduction in the extremities. CV% was observed with values
ranging from 24.74 to 59.91%. The nozzle XP20 presented seven configurations with
CV% below 40% and nozzles XT010 and XP10 with six and two respectively. The
increase in pressure and height promoted elongation of the profile and increase the
range of spray application, ranging from 1.95 to 5.00 m. The spray nozzles have
potential for use in the application of herbicides that do not require good coverage and
uniformity of the target as the systemic herbicides applied in post-emergency and
herbicides applied in pre-emergency
Avaliação de pontas de pulverização sob diferentes condições operacionais.
CNPqObjetivou-se, neste trabalho, avaliar diferentes pontas de pulverização em diferentes condições operacionais, visando fornecer subsídios para a seleção correta de pontas de pulverização para aplicação de agrotóxicos. O
trabalho constou de dois experimentos. No primeiro foi avaliado a deposição de gotas no dossel da soja pelas pontas de pulverização XR11002 (XR), TXA-8002 (TX), TT11002 (TT) e TJ60-8002 (TJ), submetidas a pressões de 827, 552 e 276 kPa. Quantificou-se o diâmetro da mediana volumétrica (DMV) da população de gotas, densidade de gotas (gotas cm-2) e porcentagem de cobertura. A coleta das gotas foi realizada em três posições no dossel da soja: terço superior, médio e inferior da planta em esquema fatorial 4x3x3 (quatro
pontas de pulverização, três pressões e três posições no dossel da planta) em um DBC com quatro repetições. No segundo experimento avaliou-se as características técnicas das pontas de pulverização LA-1JC e SR-1 sob diferentes condições operacionais. Avaliou-se o perfil de distribuição das pontas em bancada de ensaios padronizada seguindo a norma ISO 5682/2 em alturas de 30, 40 e 50 cm, determinou-se a vazão das pontas, o espectro de gotas, o ângulo de pulverização esquerdo, direito e total. Todas as características avaliadas foram submetidas as pressões de 100, 200 e 300 kPa. Observou-se no experimento de deposição de calda no dossel da soja, que a população de gotas apresentou maior DMV no terço superior da planta,
entretanto a ponta TJ proporcionou gotas com DMV homogêneo nas posições avaliadas. Independente da ponta de pulverização utilizada, a pressão de 276kPa permitiu deposição de gotas com tamanho uniforme nas três posições. Para as demais pressões, maior DMV foi obtido no terço superior da planta. A ponta TJ, proporcionou cobertura do alvo semelhante nos três terços e x cobertura superior as demais pontas no terço médio e inferior da planta. As pontas promoveram maior densidade de gotas no terço superior da planta,
decrescendo à medida que se reduz a altura, exceto para ponta TJ, que apresentou densidade de gotas homogênea nas três posições. Avaliando as características técnicas das pontas SR-1e LA-1JC, observou-se perfil de distribuição contínuo para as pontas LA1-JC em todas as pressões e da SR-1 quando utilizado a pressão de 100 kPa, sendo indicado para aplicação em faixa. A ponta SR-1 nas pressões de 200 e 300 kPa apresentou perfil descontínuo, sendo indicado para aplicação em área total. Houve melhor uniformidade de distribuição (menor coeficiente de variação), com menor espaçamento entre pontas e maior altura de barra. Para ambas as pontas, à medida que se aumentou a pressão diminuiu-se o DMV. Independente da pressão de trabalho utilizada, as pontas LA-1JC e SR-1 proporcionaram gotas extremamente grossas. O CH está adequado aos padrões para pontas de jato plano (menor que 5), apresentando boa homogeneidade no espectro de gotas em todas as pressões de trabalho. A ponta LA-1JC apresentou maior vazão em
relação a ponta SR-1, nas pressões de 200 e 300 kPa, não sendo verificada diferença quando utilizada a pressão de 100 kPa. O ângulo de pulverização esquerdo e direito foram simétricos não havendo diferenças entre pontas e pressão. Houve aumento no ângulo a medida que se aumentou a pressão para ambas as pontas.This work had the objective to evaluate different spray nozzle by different operational conditions in order to have subsidies for the correct selection of spray nozzle for pesticide application. The work consisted of two
experiments. On the first, it was evaluated the deposition of drops on the soybean canopy by spray nozzle XR11002 (XR), TXA8002 (TX), TT11002 (TT) and TJ60-8002 (TJ) exposed to pressure of 827, 552 and 276 kPa. It was quantified the volume median diameter (DMV) of the drop population, density of drops (drops cm-2) and covering percentage. The drops were collected in three positions on the soybean canopy: superior third, medium and inferior of the plant by factorial scheme 4x3x3 (four spray nozzle, three pressure and
three positions on the soybean canopy) in a totally occasional sketch with four repetitions. On the second experiment, the technical characteristics of spray nozzle LA-1JC and SR-1 were evaluated by different operational conditions. It was evaluated the pattern check of spray nozzle in test workbench following
the pattern ISO 5682/2 on heights of 30, 40 and 50 cm, determining spray nozzle outflow, drops spectrum, left, right and total angle spray. All characteristics analyzed were submitted to pressure of 100, 200 and 300 KPa.
In the experiment about the deposition of drops on the soybean canopy, it was realized that the drop population showed higher DMV on the superior third of the plant. However, the nozzle TJ provided drops with homogeneous DMV in the evaluated positions. Independent of spray nozzle utilized, the pressure of
276 KPa allowed deposition of drops with same size on the three positions. For the other pressures, it was obtained higher pressure on the superior third of the plant. The TJ nozzle provided similar covering of the aim on the three third and superior covering on the other nozzle of the medium third and xii inferior of the plant. The nozzles promoted higher density of drops on the superior third of the plant, decreasing in proportion to reduce the height, except TJ nozzle which showed homogeneous density in the three positions. Analyzing technical characteristics of SR-1 and LA-1JC nozzles, it was observed continuous pattern check to the LAI-JC nozzles in all pressure and SR-1 when utilized pressure of 100kPa that was indicated for stripe. SR nozzle showed discontinued pattern in the pressure of 200 and 300 kPa, which is indicated for application in total area. There was better uniformity in the distribution (lower rate of variation), with lower set at intervals on the nozzles
and higher bar height. For both nozzles DMV decreased in proportion to the increase of the pressure. Independent of the work pressure utilized, LA-1JC and SR-1 nozzles provided extremely dense drops. CH is adequate to the patterns of jet plane nozzle (lower than 5) showing great homogeneity in the drops spectrum in every work pressure. LA-1JC nozzle showed higher outflow than SR1, on the pressure of 200 and 300 kPa, having no difference observed when 100 kPa pressure was utilized. The left and right angle of pulverization
were symmetrical that there weren’t differences between nozzle and pressure. There was increasing on the angle in proportion to the pressure improvement on the nozzle. It is indicated TJ nozzle for pesticides application in adequate climate conditions
Relato de uma Viagem sem Dinheiro pelo Brasil, Bolívia e Peru em 2015/2016
The objective of this article is to report a moneyless trip made across Brazil, Bolivia and Peru in 70 days (December 2015 to February 2016). A spiritual and adventure path, totalizing 5,500 km. The theme choice is based on a personal need to prove that it is possible to travel without financial resources, emphasizing the human relationships. The problematic is questioning the centrality of tourism as an economic activity, something that minimizes its other perspectives. The methodology used is qualitative and bibliographical, besides the field work. The text was structured as follows: theoretical foundations that approach tourism beyond the economic bias; report, detailing the inspiration, preparation, path and experiences; and the results that are the contributions of the trip as a professional formation. After 45 hitchhikings and 33 shelters, the sociocultural nature of tourism and human hospitality were confirmed. It is concluded that sharing tourism is possible, without compulsory payment. The main references used were Cunha (2010), Campbell (2015), Trigo (2013), and others.Esta investigación tuvo como objetivo relatar un viaje sin dinero por Brasil, Bolivia y Perú durante 70 días (de diciembre/2015 a febrero/2016). Un camino espiritual y de aventuras que totalizó 5.500 km. La elección del tema parte de la necesidad personal de la estudiante en probar ser posible viajar sin recursos financieros, enfatizando las interrelaciones humanas. La problemática es el cuestionamiento de la centralidad del turismo como una actividad económica, que minimiza otras perspectivas. La metodología utilizada fue la bibliográfica de carácter cualitativo, además del trabajo de campo. El texto se estructuró de la siguiente manera: la fundamentación teórica que aborda el turismo más allá de su concepto económico; el relato detallando la inspiración, preparación, trayectoria y experiencias; y los resultados que fueron las contribuciones del viaje a la formación profesional. Después de 45 viajes a dedo y 33 refugios, se confirma la naturaleza sociocultural del turismo y de la hospitalidad. Se concluye que es posible un turismo de compartir, sin la obligatoriedad de pagar. Los principales autores utilizados fueron Cunha (2010), Campbell (2015), Trigo (2013), entre otros.O objetivo deste artigo é relatar uma viagem feita sem dinheiro pelo Brasil, Bolívia e Peru em setenta dias (dezembro de 2015 a fevereiro de 2016). Um caminho espiritual e de aventuras, totalizando 5.500 quilômetros. A escolha do tema parte da necessidade pessoal da estudante em provar ser possível viajar sem recursos financeiros próprios, enfatizando as relações humanas. A problemática é o questionamento da centralidade do turismo como uma atividade econômica, algo que minimiza suas outras perspectivas. A metodologia usada foi bibliográfica de caráter qualitativo, além do trabalho de campo. O texto foi estruturado da seguinte maneira: os fundamentos teóricos que abordam o turismo além do viés econômico; o relato, detalhando a inspiração, preparação, trajeto e experiências; e os resultados que são as contribuições da viagem para a formação profissional. Após 45 caronas e 33 abrigos, confirma-se a natureza sociocultural do turismo e da hospitalidade humana. Conclui-se ser possível um turismo de compartilhamento, sem pagamento obrigatório. As principais referências foram Cunha (2010), Campbell (2015), Trigo (2013), entre outros
Productivity and physiology of kale inoculated with entomopathogenic fungi of Amazon region to control caterpilla
The use of biological control agents such as entomopathogenic fungi is an alternative for the control of kale(Brassica oleracea L.) defoliating caterpillars. The objective was to investigate the efficacy of entomopathogenicfungi of Amazon region in the control of defoliating caterpillars in kale and their impacts on the physiologicaland agronomic responses of the crop. Field and greenhouse experiments were conducted in randomized blockdesign and completely randomized design, respectively. The treatments consisted in the application of isolatesof entomopathogenic fungi: Beauveria bassiana, Isaria sp., Metarhizium anisopliae and Trichoderma asperellum.The control treatment consisted of the application of an chemical insecticide based on deltamethrin.Variablesreferring to the development, yield and physiology of the plants were evaluated. Field results revealed thatplants treated with the fungi B. bassiana, M. anisopliae and T. asperellum showed levels of severity, number ofleaves and commercial yield that did not differ from the standard treatment; however, they showed a lowerpopulation density of the defoliating caterpillar complex. The application of the treatments with M. anisopliaeand chemical insecticide showed better photosynthetic performance. In greenhouse, the fungus T. asperellumprovided greater plant height and robustness index in relation to the treatment with chemical insecticide.The entomopathogenic fungi of Amazon region can be contributed to the integrated management of leafdefoliating caterpillars in kale. These microorganisms have similar efficiency with chemical insecticides, beingecologically and economically viable to mitigate the negative impacts caused by the systematic use ofchemicals
New records of mesoclemmys raniceps (Testudines, chelidae) for the states of amazonas, pará and Rondônia, north Brazil, including the Tocantins basin
Pandemia de covid-19 e a criação da Ficha de Investigação e Notificação Ocupacional de Doenças Infectocontagiosas (FINODI)
Mathematical Modeling of the Differential Sticking Coefficient of Clay Drilling Fluids
The main objective of this work is to propose a mathematical model for the differential sticking coefficient of clayey drilling fluids with a lubricant as an additive and evaluate the influence of differential pressure and lubricant content on filter cake thickness and permeability. Tests were carried out on fluids composed of water and 4.86% of active bentonite clay prepared in Hamilton Beach agitators at a high rotation speed (17000 rpm) for 20 minutes. After a 24-hour time-out in a closed container, lubricants were added to the fluids at different levels. To obtain the differential sticking coefficient (DSC), and the filter cake, a differential sticking tester by Fann with a spherical torque plate was used, and the filter cake thickness was determined in an extensometer. The setting time, differential pressure, and lubricant content were defined as the input variables (independent variables) to the DSC mathematical model. The differential pressure and lubricant rate were the independent variables to the mathematical model of filter cake thickness (FCT) and permeability (K), which varied according to a factorial planning, was known as a second order model. The experimental data regression was performed utilizing Statistic software, version 7.0. The results clearly showed that it was possible to obtain a statistically meaningful and predictive mathematical model for DSC. It was also observed that the increase in the lubricant content was responsible for a DSC value reduction due to the fact that the lubricant was a dispersing agent reducing the filtrate volume and the filter cake thickness, and thereby decreasing the sticking risk due to differential pressure. Finally, from the analysis of point values and response surfaces for FCT and K, it was possible to observe tendencies that made clear that the differential pressure and lubricant content influenced filter cake properties
Leucine and Its Importance for Cell Signalling Pathways in Cancer Cachexia-Induced Muscle Wasting
The anabolic effects of a supplemented diet with branched-chain amino acids, especially leucine, on skeletal muscle wasting and as a co-adjuvant in cancer treatment have been well-studied. Leucine is a precursor of protein synthesis and acts as a nutritional signal, affecting multiple metabolic processes (e.g., satiety, thermogenesis, energy efficiency, and body composition). Previous studies related to nutritional therapy have mainly focused on myopenia, which is the loss of skeletal muscle mass in some pathologies, including cancer. Leucine plays a role in the maintenance and even increase of lean body mass in healthy individuals as well as the prevention of disease states that culminate in myopenia. Herein, we review the available data addressing the mechanisms by which leucine acts as a cellular signal, thereby stimulating muscle protein synthesis, leading to the inhibition of muscle catabolism, especially in an experimental model of cancer cachexia. We also show differences found in the metabolomic and proteomic analyses, including the use of leucine in maternal diets as a preventative for muscle wasting as supported by our experimental data
Leucine-Rich Diet Modulates the Metabolomic and Proteomic Profile of Skeletal Muscle during Cancer Cachexia
Background: Cancer-cachexia induces a variety of metabolic disorders, including skeletal muscle imbalance. Alternative therapy, as nutritional supplementation with leucine, shows a modulatory effect over tumour damage in vivo and in vitro. Method: Adult rats distributed into Control (C), Walker tumour-bearing (W), control fed a leucine-rich diet (L), and tumour-bearing fed a leucine-rich diet (WL) groups had the gastrocnemius muscle metabolomic and proteomic assays performed in parallel to in vitro assays. Results: W group presented an affected muscle metabolomic and proteomic profile mainly related to energy generation and carbohydrates catabolic processes, but leucine-supplemented group (WL) recovered the energy production. In vitro assay showed that cell proliferation, mitochondria number and oxygen consumption were higher under leucine effect than the tumour influence. Muscle proteomics results showed that the main affected cell component was mitochondria, leading to an impacted energy generation, including impairment in proteins of the tricarboxylic cycle and carbohydrates catabolic processes, which were modulated and improved by leucine treatment. Conclusion: In summary, we showed a beneficial effect of leucine upon mitochondria, providing information about the muscle glycolytic pathways used by this amino acid, where it can be associated with the preservation of morphometric parameters and consequent protection against the effects of cachexia
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