MUDANÇA DO USO DA TERRA E DINÂMICA DE CARBONO ORGÂNICO DO SOLO NO PLATÔ DE IRECÊ, BAHIA

O desmatamento indiscriminado da Caatinga e sua substituição por cultivos têm causado processos de degradação do solo na região semiárida brasileira. O objetivo do estudo foi verificar a evolução, ao longo do tempo, das áreas com vegetação nativa de Caatinga por meio do uso de imagens de satélite e analisar as alterações no estoque de carbono orgânico do solo decorrentes da substituição de Caatinga por cultivos de sequeiro e irrigado na unidade geoambiental do Platô de Irecê, Bahia. Foram coletadas amostras de solos até a profundidade de 0,60 m, em áreas de Caatinga, agricultura de sequeiro e irrigada. Os resultados indicam que entre 1980 e 2007 ocorreu perda de 61,42% de área com vegetação de Caatinga; a maior redução de área de Caatinga ocorreu na década de 1980, período que a região tornou-se a maior produtora de grãos do Nordeste; a substituição da Caatinga por usos agrícolas proporcionou perda estimada de 725.000 Mg de carbono do sol

Estimatives and utilization of field capacity

Estudou-se o conceito da capacidade de campo de Veihmeyer e Hendrickson e sua versão utilizando a curva de retenção de água. O trabalho experimental de campo foi conduzido em dois solos de propriedades físico-químicas distintas: um Latossolo Vermelho-Amarelo fase arenosa e um Terra Roxa Estruturada em uma parcela de 6x4m em cada solo. Em cada parcela foram instalados 20 tensiômetros com manômetro de mercúrio em linha, distantes 0,5m um do outro e alternando as profundidades em 15 e 25 cm. As medições em laboratório para elaboração das curvas de retenção, foram realizadas usando amostras de solo com estrutura indeformada (anel volumétrico de 50 cm<sup>3</sup>). As tensões utilizadas foram 5, 10, 60 e 100 cm de água em funil de placa porosa, e 344, 1033, 3099, 5165 e 15495 cm de água em câmaras de pressão de Richards. O ajuste das curvas foi feito segundo a equação de Van GENUCHTEN (1980). As determinações da umidade a base de massa do solo nas parcelas de campo ao longo do tempo, foram realizadas com ?trado holandês? e as densidades do solo para cada local da amostragem com anéis cilíndricos. Os resultados mostraram grande variabilidade para os parâmetros potencial da água, porosidade total e granulometria, em ambos os solos e em todas as profundidades, e a necessidade de apresentar o conceito de uma forma dinâmica, enfocando medidas como fluxo de água ao longo do perfil e menos as características de sua matriz.Veihmeyer & Hendrickson?s concept of field capacity and it?s version involving the soil water retention curve, were studied using two soils with distinct physicochemical properties: one Yellow Red Latosol, sandy fase and ?Terra Roxa Estruturada?. ln 6x4m experimental plots 20 mercury manometer tensiometers were installed, along a transect, 0.5 m apart from each other, alternating the depth from 15 to 25 cm. Laboratory soil water retention curves were established using core samples of 50 cm<sup>3</sup>, submitted to suction in porous plate finnels for pressure heads of -5, -10, -60 and -100 cm of water, and submitted to pressure in pressure plate apparatus, for pressure heads of -344, -1033, -3099, -5165 and -15495 cm of water. The curves were adjusted according to Van GENUCHTEN'S (1980) model. Soil water content determinations in the field plots, as a function of time, were made using a traditional auger. Data was transformed in a volumetric basis using bulk density data obtained through the use of volumetric cylinders of 50 cm<sup>3</sup>. Results show a great variability in space and time, for soil water potential, total porosity and particle size distribution, indicating the need of a dynamic presentation of the concept, giving more emphasis to soil water fluxes within the profile, and less emphasis to soil matrix characteristics

Hourly, Daily, and Monthly Soil Temperature Fluctuations in a Drought Tolerant Crop

<div><p>ABSTRACT Soil temperature is a physical property of great agricultural importance in the soil-plant relationship and in energy exchange with the atmosphere. This study was conducted in a degraded Cambissolo Háplico Ta Eutrófíco (Cambisol; Inceptisol) in the Irecê Identity Territory, Bahia, Brazil, aiming to evaluate the hourly, daily, and monthly fluctuations of soil temperature at depth, and soil thermal diffusivity in the castor bean crop. Hourly soil temperature data from February 4, 2014, to September 30, 2015, were obtained by using thermocouple sensors (copper-constantan) horizontally installed at 0.05, 0.10, and 0.20 m depths. Soil thermal diffusivity was estimated by phase and amplitude methods. Results showed that, for most days, the soil temperature was at the level recommended for castor bean. The maximum and minimum hourly and daily soil temperatures were observed in October and July, respectively, and the maximum soil temperature values occurred at 4 p.m. (0.05 m), 5 p.m. (0.10 m), and 7 p.m. (0.20 m). Soil temperature variability is low, requiring few measurement points to estimate this factor in an area. The amplitude method led to soil thermal diffusivity values compatible with results in the literature. The absence of a relationship between thermal diffusivity and soil moisture was attributed to the clay-loam soil texture, predominance of micropores, and iron oxides allowing greater approximation to the soil particles, with high thermal diffusivity even under low soil moisture conditions.</p></div

Extruded sorghum (Sorghum bicolor L.) reduces metabolic risk of hepatic steatosis in obese rats consuming a high fat diet

The study investigated the effect of extruded sorghum flour (ESF) in a high fat diet (HFD) on biometric measurements and hepatic lipogenesis. Male Wistar rats were fed a normal diet (AIN-93M), HFD, HFD plus ESF replacing 50% cellulose and 100% corn starch (HFDS50), or HFD plus ESF replacing 100% cellulose and 100% corn starch (HFDS100) for eight weeks. ESF reduced the body mass index and liver weight of obese rats. Additionally, ESF reduced hepatic lipogenesis by increasing adiponectin 2 receptor gene expression and gene and protein expressions of peroxisome proliferator-activated receptor α (PPARα), while reducing the gene expression of sterol regulatory element-binding transcription factor 1. Molecular docking analysis revealed the affinity of ESF compounds (luteolinidin, apigeninidin, 5-methoxy-luteolinidin, and 7-methoxy-apigeninidin) with the PPAR-α receptor. Histological analysis confirmed the decreased grade of hepatic steatosis in obese rats. These data indicate the potential of ESF to reduce metabolic risk of hepatic steatosis associated with lipogenesis and obesity

Bacupari peel extracts (Garcinia brasiliensis) reduces the biometry, lipogenesis and hepatic steatosis in obese rats

The aim was to evaluate the effect of the ethanol extract of bacupari peel (EEB) on biometric measurements, hepatic lipogenesis and progression of non-alcoholic fatty liver disease (NAFLD) in obese Wistar rats. Chemical analysis of the bacupari peel extract identified 7-epiclusianone as the major constituent (140.02 mg/g) followed by morelloflavone (35.86 mg/g). Animals treated with high fat diet plus EEB (BHFD) reduced body mass index (BMI), liver weight and hepatosomatic index in relation to the obese control. The food intake was similar between hyperlipid group (HFD) groups with or without EEB. However, the normal control group (AIN-93 M) presented higher food intake and lower final weight compared to the obese control (HFD). The PPAR-α, CPT-1a and the ADIPOR2 genes expressions, and the concentration of the PPAR-α and the adiponectin protein level increased in the BHFD group in relation to the obese control. The EEB promoted reduction of the SREBP-1c gene expression and the percentage of hepatic fat and the degree of steatosis in relation to HFD. It was concluded that EEB showed a protective effect on NAFLD, as it promoted a reduction in BMI, induced lipid oxidation, reduced lipogenesis and hepatic steatosis. Moreover, our results suggest an interaction that can lead to an agonist activity of the EEB to the PPAR-α receptor

Detection of Helicobacter pylori resistance to clarithromycin and fluoroquinolones in Brazil : a national survey

AIM To evaluate bacterial resistance to clarithromycin and fluoroquinolones in Brazil using molecular methods. METHODS The primary antibiotic resistance rates of Helicobacter pylori (H. pylori) were determined from November 2012 to March 2015 in the Southern, South-Eastern, Northern, North-Eastern, and Central-Western regions of Brazil. Four hundred ninety H. pylori patients [66% female, mean age 43 years (range: 18-79)] who had never been previously treated for this infection were enrolled. All patients underwent gastroscopy with antrum and corpus biopsies and molecular testing using GenoType HelicoDR (Hain Life Science, Germany). This test was performed to detect the presence of H. pylori and to identify point mutations in the genes responsible for clarithromycin and fluoroquinolone resistance. The molecular procedure was divided into three steps: DNA extraction from the biopsies, multiplex amplification, and reverse hybridization. RESULTS Clarithromycin resistance was found in 83 (16.9%) patients, and fluoroquinolone resistance was found in 66 (13.5%) patients. There was no statistical difference in resistance to either clarithromycin or fluoroquinolones (p = 0.55 and p = 0.06, respectively) among the different regions of Brazil. Dual resistance to clarithromycin and fluoroquinolones was found in 4.3% (21/490) of patients. The A2147G mutation was present in 90.4% (75/83), A2146G in 16.9% (14/83) and A2146C in 3.6% (3/83) of clarithromycin-resistant patients. In 10.8% (9/83) of clarithromycin-resistant samples, more than 01 mutation in the 23S rRNA gene was noticed. In fluoroquinolone-resistant samples, 37.9% (25/66) showed mutations not specified by the GenoType HelicoDR test. D91N mutation was observed in 34.8% (23/66), D91G in 18.1% (12/66), N87K in 16.6% (11/66) and D91Y in 13.6% (9/66) of cases. Among fluoroquinolone-resistant samples, 37.9% (25/66) showed mutations not specified by the GenoType HelicoDR test. CONCLUSION The H. pylori clarithromycin resis­tance rate in Brazil is at the borderline (15%-20%) for applying the standard triple therapy. The fluoroqui­nolone resistance rate (13.5%) is equally concerning