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1.
Environ Monit Assess ; 196(10): 958, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39302497

RESUMEN

Soil salinization stands as a prominent global environmental challenge, necessitating enhanced assessment methodologies. This study is dedicated to refining soil salinity assessment in the Lake Urmia region of Iran, utilizing multi-year data spanning from 2015 to 2018. To achieve this objective, soil salinity was measured at 915 sampling points during the 2015-2018 timeframe. Simultaneously, remote sensing data were derived from surface reflectance data over the same study period. Four distinct scenarios were considered such as a newly developed spectral index (Scenario I), the newly developed index combined with other salt-based spectral indices from the literature (Scenario II), indirect spectral indices based on vegetation and soil characteristics (Scenario III), and the amalgamation of both direct and indirect spectral indices (Scenario IV). Linear Regression (LR), Support Vector Machine (SVM), and Random Forest (RF) were employed to assess soil salinity. The measured data divided to 75% of the data as the calibration dataset, while the remaining 25% constituted the validation dataset. The findings revealed a correlation between soil salinity and spectral indices from the literature, with a range of -0.53 to 0.51, while the newly developed spectral index exhibited a stronger correlation (r = 0.59). Furthermore, RF yielded superior results when using the newly developed spectral index (Scenario I). Overall, SVM emerged as the most effective model (ME = -9.678, R2 = 0.751, and RPIQ = 1.78) when integrating direct and indirect spectral indices (Scenario IV). This study demonstrates the efficacy of combining machine learning techniques with a blend of newly developed and existing spectral indices from the literature for the monitoring of soil salinity, particularly in arid and semi-arid regions.


Asunto(s)
Monitoreo del Ambiente , Lagos , Salinidad , Suelo , Monitoreo del Ambiente/métodos , Suelo/química , Lagos/química , Irán , Máquina de Vectores de Soporte , Tecnología de Sensores Remotos
2.
J Nutr Health Aging ; 25(4): 454-461, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33786562

RESUMEN

BACKGROUND: There is equivocal evidence about beneficial properties of omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA) for older adults. OBJECTIVE: This study investigated the relationship between circulating ω-3 LCPUFA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels and their corresponding dietary intakes with cognition and physical function in a cohort of community-dwelling older adults at risk of dementia. METHODS: A cross-sectional analysis was conducted among 142 community-dwelling older adults (60-85 years) with subjective memory complaints. Erythrocyte fatty acids (ω-3 LCPUFA) and the omega-3 index were measured; dietary DHA and EPA were assessed with a LCPUFA specific questionnaire. Cognition was measured using the Cogstate computerised battery and Trail-making tests. Muscle strength was assessed by grip strength and physical function via the four-square step test, 30-second sit-to-stand, timed up-and-go test, and 4-m walk test. Multiple regression analysis was used to assess the relationship between erythrocyte ω-3 LCPUFA, dietary intake, cognitive and physical function. RESULTS: Higher dietary DHA and EPA were associated with better global cognitive function (DHA: ß=0.164, p=0.042; EPA: ß=0.188, p=0.020). Higher dietary EPA was associated with better attention/psychomotor composite scores (ß=0.196, p=0.024), mobility (four-square step test: ß=-0.202, p=0.015) and gait speed (4m walk test: ß=-0.200, p=0.017). No associations were found between erythrocyte ω-3 LCPUFA and cognitive or functional performance measures. CONCLUSIONS: In community-dwelling older adults with subjective memory complaints, higher dietary ω-3 LCPUFA intake was associated with better cognitive and physical function, supporting the evidence that ω-3 fatty acids play a role in optimising physical and cognitive health during ageing.


Asunto(s)
Cognición/efectos de los fármacos , Ácidos Grasos Omega-3/sangre , Salud/normas , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
3.
Phytother Res ; 23(6): 797-800, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19172582

RESUMEN

The enhancement of the antibacterial activity of ampicillin by different extracts of Berberis integerrima fruits was evaluated against Staphylococcus aureus. Disk diffusion and agar dilution methods were used to determine the antibacterial activity of ampicillin in the absence and presence of different plant extracts or various fractions eluted by column chromatography. A clinical isolate of S. aureus was used as a test strain. The active component of B. integerrima fruits involved in the enhancement of ampicillin activity was purified and identified as 1-methyl malate using different spectroscopic methods. Both the ethanol extract of B. integerrima fruits and 1-methyl malate enhanced the antibacterial activity of ampicillin. The total extract as well as 1-methyl malate increased the antibacterial activity of ampicillin against the test strain. The potency of ampicillin against the test strain was increased 64-fold when tested with a sub-toxic concentration of total extract of B. integerrima fruits. Also, 1-methyl malate increased the bactericidal activity of ampicillin. In the presence of 2 mg/mL of 1-methyl malate the MIC of ampicillin for S. aureus decreased from 128 to 1 microg/mL (128-fold).


Asunto(s)
Ampicilina/farmacología , Antibacterianos/farmacología , Malatos/farmacología , Extractos Vegetales/farmacología , Staphylococcus aureus/efectos de los fármacos , Berberis/química , Sinergismo Farmacológico , Frutas/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular
4.
Nucleosides Nucleotides Nucleic Acids ; 25(9-11): 1201-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17065091

RESUMEN

Activation of nucleoside analogues is dependent on kinases and 5'-nucleotidases and the balance between the activity of these enzymes. The purpose of this study was to analyze deoxycytidine kinase, deoxyguanosine kinase, and 4 different 5'-nucleotidases during cell cycle progression in MOLT-4 cells. The activity of both kinases was cell cycle dependent and increased during proliferation while the activity of cytosolic 5'-nucleotidase I decreased. We could show that the kinase activity was higher than the total nucleotidase activity, which was unchanged or decreased during cell cycle progression. These data may be important in designing modern combination therapy with nucleoside analogues.


Asunto(s)
5'-Nucleotidasa/biosíntesis , Ciclo Celular , Citosol/enzimología , Desoxicitidina Quinasa/biosíntesis , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Fosfotransferasas (Aceptor de Grupo Alcohol)/biosíntesis , Línea Celular Tumoral , Medio de Cultivo Libre de Suero/farmacología , Colorantes Fluorescentes/farmacología , Humanos , Concentración 50 Inhibidora , Nucleósidos/química , Sales de Tetrazolio/farmacología , Tiazoles/farmacología , Factores de Tiempo
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