Utjecaj prethodne obrade ultrazvukom na sušenje dinje i modeliranje temperaturnog profila pomoću računalne dinamike fluida

Research background: Drying is one of the most traditional processes of food preservation. Optimizing the process can result in a competitive product on the market regarding its price and quality. A common method in use as a pretreatment to drying is ultrasound. The goal of this work is to analyze different drying methods with and without applying ultrasound (US) pretreatment, on heat and mass transfer, simulating numerically the temperature profile by computational fluid dynamics (CFD). Experimental approach: The melon slices were pretreated with ultrasound for 10 (US10), 20 (US20) and 30 (US30) min at 25 kHz, and the water loss and solid gain were evaluated. Samples were dried at different temperatures (50, 60 and 70 °C). The effective diffusivity was estimated, and experimental data were modelled using empirical models. The airflow in the dryer and the temperature profile in the melon slice were simulated via computational fluid dynamics (CFD). Results and conclusions: Ultrasound pretreatment reduced the drying time from 25% (samples US20 and US30 at 50 °C) to 40% (samples US20 and US30 at 70 °C). The two-term exponential model presented the best fit to the experimental data, and the diffusivity coefficients showed a tendency to increase as the time of exposure of the melon to ultrasonic waves increased. Pretreatment water loss and solid gain behaviour and drying kinetic and diffusion data were used to choose the best experimental conditions to be simulated with CFD. The heat transfer modelling through CFD showed that the temperature distribution along the melon slice was representative. Therefore, the profile obtained via CFD satisfactorily describes the drying process. Novelty and scientific contribution: The use of simulation tools in real processes allows the monitoring and improvement of existing technologies, such as food drying processes, that involve complex mechanisms, making it difficult to obtain some data. Application of CFD in the drying processes of fruits and vegetables is still very recent, being a field little explored. There is no record in the literature that uses CFD in the drying of melon.Pozadina istraživanja. Sušenje je jedan od najtradicionalnijih postupaka konzerviranja hrane. Optimiranjem postupka sušenja dobivaju se proizvodi koji su cijenom i kakvoćom konkurentni na tržištu. Primjena ultrazvuka je uobičajena metoda prethodne obrade proizvoda prije sušenja. Svrha je ovoga rada bila ispitati različite metode sušenja s prethodnom obradom ultrazvukom ili bez nje na prijenos topline i mase, te napraviti simulaciju temperaturnog profila primjenom računalne dinamike fluida. Eksperimentalni pristup. Kriške dinje su prethodno obrađene ultrazvukom pri 25 kHz tijekom 10, 20 i 30 min, te su izmjereni gubitak vode i povećanje mase suhe tvari uzoraka. Uzorci su zatim sušeni pri temperaturama od 50, 60 i 70 °C. Procijenjena je efektivna difuzivnost vode, a eksperimentalni su rezultati oblikovani pomoću empirijskih modela. Protok zraka u sušari i promjena temperature u krišci dinje simulirani su pomoću računalne dinamike fluida. Rezultati i zaključci. Prethodnom obradom ultrazvukom vrijeme se sušenja smanjilo od 25 % (za uzorke obrađene ultrazvukom tijekom 20 i 30 min, a zatim sušene na 50 °C) do 40 % (za uzorke obrađene ultrazvukom tijekom 20 i 30 min, a zatim sušene na 70 °C). Dvočlani eksponencijalni model najbolje je opisao eksperimentalne podatke, a koeficijent difuzivnosti povećavao se s produljenjem obrade uzoraka dinje ultrazvukom. Gubitak vode i povećanje mase suhe tvari tijekom prethodne obrade ultrazvukom, te kinetika sušenja i podaci o difuzivnosti korišteni su za odabir najboljih eksperimentalnih uvjeta i njihovu simulaciju pomoću računalne dinamike fluida. Modeliranjem prijenosa topline potvrđeno je da je distribucija topline u kriški dinje bila u skladu s očekivanjima. Stoga je zaključeno da temperaturni profil dobiven računalnom dinamikom fluida na zadovoljavajući način opisuje postupak sušenja. Novina i znanstveni doprinos. Alati za simulaciju stvarnih procesa omogućuju praćenje i poboljšanje postojećih postupaka obrade hrane kao što je sušenje, koje uključuje kompleksne mehanizme, što otežava dobivanje podataka. Primjena računalne dinamike fluida pri sušenju voća i povrća je noviji i slabo istražen postupak. U znanstvenoj literaturi nema podataka o upotrebi računalne dinamike fluida pri sušenju dinje

Diagnóstico da variabilidade espacial e manejo da fertilidade do solo no Cerrado

O conhecimento da variabilidade espacial dos atributos químicos do solo permite um manejo mais eficiente da fertilidade. Objetivou-se caracterizar a variabilidade espacial dos atributos químicos e realizar o manejo da fertilidade de um Latossolo Vermelho distrófico no cerrado piauiense por meio das ferramentas da geoestatística. Para a realização do estudo foram retiradas 100 amostras de solo na camada de 0,00-0,20 m, em grid de 100 x 30 m. Foram avaliados o pH, fósforo, potássio, cálcio, magnésio, alumínio trocável, acidez potencial, capacidade de troca de cátions total, capacidade de trocas de cátions efetiva, soma de bases, saturação por alumínio e saturação por bases. Todas as variáveis apresentaram dependência espacial, indicando que o número de amostra foi suficiente para mapear a área em estudo, utilizando-se técnicas da geoestatística. O uso da geoestatística e a elaboração dos mapas de isolinhas por krigagem permitem a visualização das zonas de manejo da fertilidade do solo onde ocorrem os maiores e menores níveis dos atributos químicos avaliados. Além da elaboração dos mapas diagnóstico da fertilidade e da recomendação de fertilizantes e corretivos. A geoestatística pode ser usada como ferramenta para estimar os indicadores da fertilidade do solo, possibilitando orientar o manejo da fertilidade para áreas específicas

Frequency of intestinal parasites in patients attended at a university hospital in Maceió, state of Alagoas, Brazil

The aim of this study was to analyze the parasitological tests of a population at a public hospital in Maceió-AL. A descriptive study was made between January and July of 2015 analyzing the parasitological tests of a population at a public hospital in Maceió-AL. Variables such as gender, age, positive tests, protozoan species, helminths species and parasitic associations were analyzed. Out of 1.581 tests, 806 (51%) tested positive. Regarding gender, 535 (67%) were from women. Helminths were the most predominant infections (63.94%), compared to protozoans (36.06%). The Helminths with the highest number of infections were: Ascaris lumbricoides (93.23%), Trichuris trichiura (2.32%) and Enterobius vermicularis (1.26%). Among protozoans, Endolimax nana and Entamoeba coli corresponded to 78.09% and 15.91% respectively. Although non pathogenic, it suggests fecal contamination. According to the degree of parasitism, 84.0% were monoparasitism. It can be concluded that the number of positive tests for enteroparasites was high, mainly in men. The species A. lumbricoides was the main helminth detected, while E. nana was the main protozoan found in the tests. The age group between 24 and 59 years old was the one that had the highest amount of positive tests. The results observed strengthen the need for the implementation of prevention measures for intestinal parasitic infections

Resistance exercise with blood flow restriction elicits perceptual responses similar to high-load resistance exercise in women with type 2 diabetes: a crossover and randomized study

Introduction: Physical training with blood flow restriction (BFR) may provide health benefits for people with diabetes. However, the negative effects cannot be overlooked. Aim: This study aimed to analyze the acute effect of resistance exercise BFR on the rating of perceived exertion (RPE) and subjective perception of pain in untrained women with type 2 diabetes (T2DM). Methods: Ten untrained women with T2DM (56.9 ± 7.4 years; diagnostic time: 10.6 ± 4.1 years) participated in this study. Participants attended a local gym for four non-consecutive days. Initially, predictive values of one maximum repetition (1RM) and arterial occlusion pressure (AOP) were measured. In random order, second, third, and fourth visits were allocated to the following: high-load (HL) exercise (65% 1RM; three sets of 10 repetitions), low-load (LL) exercise (20% of 1RM; three sets of 15 repetitions), and LL exercise with BFR (LL+BFR) (20% 1RM; three sets of 15 repetitions; 50% of AOP). RPE and pain perception were assessed immediately after each set. RPE increased significantly over the sets for all exercise protocols (p<0.05). The perception of pain increased significantly throughout the sets only in the HL and LL+BFR exercise protocols (p<0.05). LL+BFR and HL exercises showed similar RPE values and pain perception, but significantly higher than the LL exercise (p<0.05). We conclude that LL resistance exercise with BFR promotes perceptual responses similar to traditional HL exercise in untrained women with T2DM

Atributos morfogênicos de pastos de capim-mombaça adubados com resíduo de laticínio.

A morfogênese determina o crescimento da planta, e está, dentre outros fatores, sob influência do aporte de nutrientes. Neste contexto, objetivou-se com este trabalho avaliar o efeito do uso de águas residuais da indústria de laticínios (RLL) como fornecedor de nutrientes, sobre características morfogênicas do capimmombaça. Para isso foram estudadas seis doses de resíduo líquido de laticínio, correspondentes a: 10; 50; 100; 150; 200 e 400 m³ ha-¹ avaliadas em quatro ciclos produtivos e comparadas à adubação química. Os tratamentos foram dispostos em delineamento em blocos casualisados sendo arranjados em quatro repetições. Foram mensuradas as características de expansão e aparecimento foliar, senescência foliar, alongamento do colmo e perfilhamento. A aplicação de águas residuárias da indústria de laticínios influenciou (P<0,05) positivamente a taxa de alongamento foliar (TAlF), taxa de aparecimento foliar (TApF), taxa de alongamento de colmo (TAlH) e a taxa de aparecimento de perfilhos (TApP). Houve diminuição da taxa de senescência foliar (TSF) e do filocrono na gramínea. A aplicação de 400 m³ ha-¹ de RLL elevou as taxas morfogênicas do capim-mombaça, substituindo até 25% da adubação fosfatada e 100% da adubação potássica, possuindo também, efeito residual positivo no crescimento do capim. O resíduo líquido de laticínio é potencial fornecedor de potássio para o pasto de capim-mombaça.The morphogenesis determines the model of plant growth, and is, among other factors, under the influence of nutrient availability. In this context, the aim of this work was to evaluate the effect of using wastewater from the dairy industry (RLL) as a supplier of nutrients in the morphogenesis of grass Mombaça. For this we studied six doses of liquid dairy waste, corresponding to: 10, 50, 100, 150, 200 and 400 m³ ha-1 evaluated in four production cycles and compared to chemical fertilizer. The treatments were arranged in a completely randomized design with four replications compounds. We measured the characteristics of expansion and leaf appearance, leaf senescence, stem elongation and tillering. The application of wastewater from the dairy industry has positively influenced the leaf elongation rate, leaf appearance rate, stem elongation rate and the rate of tillering. A reduction in the rate leaf senescence and the phyllochron in the grass. The application of 400 m³ ha-¹ RLL guarantees satisfactory morphogenic indices in intensive grazing system, replacing up to 25% of phosphorus and potassium fertilization of 100%, having also a positive residual effect on the growth of grass. The liquid waste is a potential supplier of dairy grazing potassium for the pastures

Atributos químicos de um Neossolo Quartzarênico sob capimmarandu adubado com resíduo líquido de frigorífico

This study was conducted to evaluate the effect of liquid waste of bovine slaughter (RLF) on the chemical characteristics of a Entisol under pasture grass Marandu. We applied four levels of RLF (0, 37.5, 75, 112.5 m³ ha-1). The experimental design was randomized blocks. The soil samples were collected at 0-10, 10-20, 20-30, 30-40 cm, deep five replicates, which were analyzed in pH, available P and K+, Ca2+, Mg2+ and Al3+, CTCpH7,0, CTCeffective, organic matter content and potential acidity (H+ Al3+). We calculated the saturation of exchangeable bases (V%) and aluminum (m%). The applications of RLF in doses of 75 and 112.5 m³ ha-1 reduced the pH and level of Al3+. We observed increased of the value the V% at 0-10 cm and CTCeffective in 10-20 cm. The organic matter content had no significant increases for the implementation of RLF. The Mg2+ increased in the 30-40 cm layer at 112.5 m³ ha-1. The results suggest that application of 37.5 m³ ha-1 increases the pH and Ca2+ and K+ at a depth of 0-10 cm and the value of CTCpH7,0 to 30 cm. The pH, total bases, CTC, CTCpH 7,0 , saturation on base, K+, Ca2+, Mg2+ were influenced by the depth with higher values in the 0-10 cm depth compared with other in all the treatments. Este experimento foi realizado com o objetivo de avaliar o efeito da aplicação de resíduo líquido de frigorífico (RLF) sobre as características químicas de um Neossolo Quartzarênico Órtico típico sob pastagem de capim-Marandu. Foram aplicadas quatro doses de RLF (0; 37,5; 75; 112,5 m³ ha- 1). O delineamento experimental utilizado foi em blocos inteiramente casualizados. Foram coletadas amostras de solo nas profundidades de 0-10, 10-20, 20-30, 30-40 cm, em cinco repetições, nas quais foram analisados pH, P e K+ disponíveis, Ca2+, Mg2+ e Al3+ trocáveis, CTCpH7,0, CTCefetiva, teores de matéria orgânica e acidez potencial (H+Al) após 90 dias da aplicação do resíduo líquido. Foi calculada a saturação por bases trocáveis (V%) e por alumínio (m%). A aplicação de RLF nas doses de 75 e 112,5 m³ ha-1 reduziram o pH e os teores de Al3+ e aumentaram a V% na camada de 0-10 cm e a CTCefetiva na camada de 10-20 cm. Os teores de matéria orgânica não foram influenciados pela aplicação do RLF. Os teores de Mg2+ aumentaram na camada 30-40 cm na dose de 112,5 m³ ha-1. Os resultados evidenciam que a aplicação de 37,5 m³ ha-1 aumentou o pH e os teores de Ca2+ e K+ na profundidade de 0-10 cm e o valor da CTCpH7,0 de 0 a 30 cm. O pH, soma de bases, CTC efetiva, CTC pH 7, saturação por bases, K+, Ca2+, Mg2+ foram influenciados pela profundidade com maiores valores na camada de 0-10 cm em relação às demais, em todos os tratamentos