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1.
Environ Monit Assess ; 196(1): 37, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38093159

RESUMO

Soil erosion is a destructive consequence of land degradation caused by deforestation, improper farming practices, overgrazing, and urbanization. This irreversible effect negatively impacts the limited renewable soil resource, causing soil truncation, reduced fertility, and unstable slopes. To address the anticipation of erosion modulus resulting from long-term land use and land cover (LULC) changes, a study was conducted in the Swat District of Khyber Pakhtunkhwa (Kpk), Pakistan. The study aimed to predict and evaluate soil erosion concerning these changes using remote sensing (RS), geographic information systems (GIS), and the Revised Universal Soil Loss Equation (RUSLE) model. We also evaluated the impact of the Billion Tree Tsunami Project (BTTP) on soil erosion in the region. Model inputs, such as rainfall erosivity factor, topography factor, land cover and management factor, and erodibility factor, were used to calculate soil erosion. The results revealed that significant soil loss occurred under 2001, 2011, and 2021 LULC conditions, accounting for 67.26%, 61.78%, and 65.32%, falling within the category of low erosion potential. The vulnerable topographical features of the area indicated higher erosion modulus. The maximum soil loss rates observed in 2001, 2011, and 2021 were 80 t/ha-1/year-1, 120 t/ha-1/year-1, and 96 t/ha-1/year-1, respectively. However, the observed reduction in soil loss in 2021 as compared to 2001 and 2011 suggests a positive influence of the BTTP on soil conservation efforts. This study underscores the potential of afforestation initiatives like the BTTP in mitigating soil erosion and highlights the significance of environmental conservation programs in regions with vulnerable topography.


Assuntos
Monitoramento Ambiental , Solo , Monitoramento Ambiental/métodos , Conservação dos Recursos Naturais/métodos , Sistemas de Informação Geográfica , Erosão do Solo
2.
PLoS One ; 18(10): e0288024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883381

RESUMO

Hepatitis B disease is an infection caused by a virus that severely damages the liver. The disease can be both acute and chronic. In this article, we design a new nonlinear SVEICHR model to study dynamics of Hepatitis B Virus (HBV) disease. The aim is to carry out a comprehensive mathematical and computational analysis by exploiting preventive measures of vaccination and hospitalization for disease control. Mathematical properties of proposed model such as boundedness, positivity, and existence and uniqueness of the solutions are proved. We also determine the disease free and endemic equilibrium points. To analyze dynamics of HBV disease, we compute a biologically important quantity known as the reproduction number R0 by using next generation method. We also investigate the stability at both of the equilibrium points. To control the spread of disease due to HBV, two feasible optimal control strategies with three different cases are presented. For this, optimal control problem is constructed and Pontryagin maximum principle is applied with a goal to put down the disease in the population. At the end, we present and discuss effective solutions obtained through a MATLAB code.


Assuntos
Vírus da Hepatite B , Hepatite B , Humanos , Hepatite B/epidemiologia , Dinâmica não Linear , Vacinação , Reprodução
3.
Artigo em Inglês | MEDLINE | ID: mdl-36247229

RESUMO

To understand dynamics of the COVID-19 disease realistically, a new SEIAPHR model has been proposed in this article where the infectious individuals have been categorized as symptomatic, asymptomatic, and super-spreaders. The model has been investigated for existence of a unique solution. To measure the contagiousness of COVID-19, reproduction number R 0 is also computed using next generation matrix method. It is shown that the model is locally stable at disease-free equilibrium point when R 0 < 1 and unstable for R 0 > 1 . The model has been analyzed for global stability at both of the disease-free and endemic equilibrium points. Sensitivity analysis is also included to examine the effect of parameters of the model on reproduction number R 0 . A couple of optimal control problems have been designed to study the effect of control strategies for disease control and eradication from the society. Numerical results show that the adopted control approaches are much effective in reducing new infections.

4.
Toxicol Ind Health ; 38(8): 470-480, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35700117

RESUMO

The objective of the present research was to determine if dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) alone and combined exposure induced pathological alterations in laboratory reared albino mice. Adult male mice were equally divided (n = 10) into Control, corn oil (CO), DBP, DEHP, and DBP+DEHP treated groups. Dibutyl phthalate (250 mg/kg), DEHP (300 mg/kg), and DBP+DEHP (250+300 mg/kg), respectively, were administered by oral gavage mixed in corn oil (0.2 mL) for 28 days. All animals were sacrificed following 28 days of treatment and blood was collected for serum lipid profiles and liver function tests. Liver samples were also collected for observation of histological changes. Microphotographs of hematoxylin and eosin-stained sections were used for computer-based micrometry. CO, DBP, DEHP, and DBP+DEHP treatment resulted in a significant increase in the mean body and liver weights as compared with the Control group. Histological examination of the livers with DBP and/or DEHP treatment showed marked alterations leading to hepatic hypertrophy. In the treated groups, a significant increase in the mean number of mononucleated, binucleated cells, and oval cells per unit area was noticed with disorganized trabecular arrangement as compared with the Control group. Treatment with DBP and/or DEHP resulted in large regeneration zones in the liver and an increased relative nucleo-cytoplasmic index of mononuclear shepatocytes when compared with the Control group. All treatments caused a significant increases in the liver enzymes and proteins as well as altered serum cholesterol, triglycerides, LDL, and VLDL levels. The histopathological and serological findings confirmed the toxic potentials to hepatic tissue of DBP and DEHP either given alone or in combination.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Animais , Óleo de Milho , Dibutilftalato/toxicidade , Dietilexilftalato/toxicidade , Fígado/metabolismo , Masculino , Camundongos
5.
Andrologia ; 54(8): e14480, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35670728

RESUMO

This study was designed to investigate testicular and male reproductive tract histopathologies and lipid profile against di-ethylhexyl phthalate (DEHP) exposure in mice and curative potentials of aqueous garlic (Allium sativum) extract. Four groups (n = 10) were named and treated as follow (a) control (C): (normal feed and drinking water + 0.2 ml corn oil); (b) aqueous garlic extract group (AGE): (500 mg/kg body weight of aqueous garlic extract); (c) DEHP group: (500 mg/kg body weight of DEHP, dissolved in corn oil; (d) AGE + DEHP group (500 mg/kg body weight garlic aqueous extract, and DEHP 500 mg/kg body weight dissolved in corn oil). The doses were given once daily through gavages for 28 days and on the 29th day, all the animals were euthanized through cervical dislocation and reproductive organs and blood samples were collected. The results showed that exposure to DEHP caused a significant effect on body weight, testicular weight, serum cholesterol, triglycerides, lipid profile, average cross-sectional area (ACSA) of the seminiferous tubule, ACSA of the lumen of seminiferous tubule, spermatogenic cells, Leydig's cells number, vas deferens diameter, lumen, muscular thickness, and epithelial cell height of vas deferens. This study revealed that exposure to DEHP can be injurious to male reproductive health and aqueous garlic extract can decrease the toxic effects of DEHP in male mice.


Assuntos
Dietilexilftalato , Alho , Animais , Antioxidantes/farmacologia , Peso Corporal , Óleo de Milho/farmacologia , Dietilexilftalato/toxicidade , Masculino , Camundongos , Ácidos Ftálicos , Ratos , Ratos Sprague-Dawley , Testículo
6.
ACG Case Rep J ; 3(4): e182, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28119933
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