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1.
Int J Phytoremediation ; 26(5): 784-792, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37846073

RESUMO

In semi-arid regions, is necessary to explore strategies to mitigate abiotic stresses such as water deficit and salinity. This study aimed to evaluate the stress tolerance capacity of three species subjected to different water regimes and salinity levels, based on dry matter production and water use efficiency (WUE). The species Handroanthus impetiginosus, Vachellia farnesiana, and Amburana cearensis were evaluated in combination with different water regimes (50%, 75%, and 100% of reference evapotranspiration - ET0) and salinity levels (0.18, 1.50, and 1.90 dS m-1). The results show that biomass accumulation increased at 50% and 75% ET0, while the WUE decreased at 100% ET0. The salinity level (1.90 dS m-1) caused reductions in leaf dry biomass (LDB), total dry biomass (TDB), LDB/TDB ratio, and WUE. The negative effects of high salinity on plant height were greater with the application of 75% ET0. The highest WUE was obtained at 50% ET0 for A. cearensis and H. impetiginosus, while V. farnesiana obtained the highest WUE at 75% ET0. A. cearensis exhibited the highest biomass accumulation (2.58 g) and WUE (0.21 g L-1). Overall, the species can tolerate drought and salinity conditions, being sensitive to high salinity concentrations during their initial growth.


The Caatinga is characterized by low water availability and soil salinization. Therefore, assessing the ability of native species to cope with these conditions allows for their utilization in reforestation programs in drought and salinity-exposed environments. Studies on the combined effects of these factors are scarce. The results indicated that native species show tolerance to drought and salinity conditions, albeit with some reductions in biomass production and water use efficiency at high NaCl concentrations. Among the species, A. cearensis performed the best under water and salinity stress conditions.


Assuntos
Fabaceae , Tabebuia , Salinidade , Água , Tolerância ao Sal , Biodegradação Ambiental , Estresse Fisiológico
2.
Sci Total Environ ; 895: 165102, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356760

RESUMO

Some strategies can optimise the use of water in crops under deficit, either by increasing yield or by reducing actual crop evapotranspiration (ET), to promote the sustainable intensification of production systems. The objective was to evaluate how the spacing, planting orientation, nitrogen fertilisation and intercropping strategies impact the dynamics of water in the soil, ET partitioning, and water use indicators for forage cactus and cactus-sorghum intercropping. Four experiments were conducted between 2018 and 2020 in the Brazilian semi-arid region. In the first two sites (I and II), the cladodes of the intercropped forage cactus and sorghum were spaced at 0.10, 0.20, 0.30, 0.40 and 0.50 m with rows-oriented east-west and north-south. In site III, the intercropped rows were spaced at 1.00, 1.25, 1.50 and 1.75 m. Site IV, which contained the forage cactus crop exclusively, was treated with four nitrogen levels (50, 150, 300 and 450 kg N ha-1). The management interventions improved water use more by increasing dry matter than by reducing ET in the cropping system. Intercropping promoted the greatest increase in water productivity (130 %). Increasing N doses in the forage cactus-only crop reduced ET by up to 39 % but increased deep drainage losses by up to 365 %. The most promising management practices for optimising water resources were as follows: spacing of 0.10 m between cactus plants in the intercropping trial under east-west row orientation, as it promoted greater water use efficiency (76 %); spacing of 0.30 m in the north-south orientation; and row spacing of 1.50 m, as it improved water productivity (6.89 kg m-3). Thus, interventions in management should be adopted to optimise water use in intercropping systems with forage cactus, aiming at sustainable intensification in dry environments.


Assuntos
Agricultura , Sorghum , Água , Nitrogênio , Zea mays , Grão Comestível , Fertilização
3.
Biomed Res Int ; 2014: 316082, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24895565

RESUMO

Antibiotic resistance is considered one of the world's major public health concerns. The main cause of bacterial resistance is the improper and repeated use of antibiotics. To alleviate this problem, new chemical substances against microorganisms are being synthesized and tested. Thiazolidines are compounds having many pharmacological activities including antimicrobial activities. For this purpose some thiazolidine derivatives substituted at position 5 in the thiazolidine nucleus were synthesized and tested against several microorganisms. Using a disc diffusion method, antimicrobial activity was verified against Gram-positive, Gram-negative, and alcohol acid resistant bacteria and yeast. The minimum inhibition concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined. All derivatives showed antimicrobial activity mainly against Gram-positive bacteria, with MIC values ranging from 2 to 16 µg/mL.


Assuntos
Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/síntese química , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Tiazolidinas/administração & dosagem , Tiazolidinas/síntese química , Relação Dose-Resposta a Droga , Dose Letal Mediana
4.
Eur J Obstet Gynecol Reprod Biol ; 155(2): 204-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21193261

RESUMO

OBJECTIVE: To evaluate the outcome of CIN 2 diagnosed by colposcopy-directed biopsy in women followed without treatment for 12 months and to verify whether the regression and progression of this lesion are associated with the woman's age at diagnosis and age at first sexual intercourse. STUDY DESIGN: Women diagnosed with CIN 2 by biopsy and with previous cervical smear showing LSIL were included in this cohort study and followed up for one year with cervical smear and colposcopy every three months. The rates of progression, persistence and regression of the CIN 2 were evaluated. The Kruskal-Wallis test was used to analyze the woman's age at diagnosis, age at first sexual intercourse and interval since the first sexual intercourse according to the CIN 2 outcome, assuming a significance level of 5%. RESULTS: At the end of 12 months of follow-up the CIN 2 regression rate was 74% (31/42), progression rate to CIN 3 was 24% (10/42) and in one case CIN 2 persisted (2%). Among women who had regression, this event was detected in the first six months of follow-up in 26 of the 31 cases. There was no statistically significant association between the evolution of CIN 2 and the woman's age at diagnosis, age at first sexual intercourse and interval since first sexual intercourse. Women whose lesions were restricted to one quadrant were more likely to have CIN 2 regression at three-month follow-up compared with women with a lesion extending to one or more quadrants (OR: 6.50; 95% CI: 1.20-35.23). CONCLUSIONS: The results of this study indicate that the majority of CIN 2 diagnosed by biopsy in women with previous Pap smear showing LSIL will regress in 12 months and therefore an expectant approach could be considered in these cases, not only for young women. Nevertheless these findings are not conclusive, and larger studies are required in order to certify when it is safe to adopt expectant management for CIN 2.


Assuntos
Progressão da Doença , Regressão Neoplásica Espontânea , Displasia do Colo do Útero/fisiopatologia , Adolescente , Adulto , Fatores Etários , Biópsia , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/fisiopatologia , Coito , Colposcopia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Teste de Papanicolaou , Estatísticas não Paramétricas , Fatores de Tempo , Carga Tumoral , Esfregaço Vaginal , Adulto Jovem , Displasia do Colo do Útero/diagnóstico
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