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1.
Sci Total Environ ; 896: 165162, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37379919

RESUMEN

Large rivers, which act as natural integrators of surface processes, contribute massive volume of terrestrial materials to the coastal oceans. However, the accelerated climate warming and increasing anthropogenic activities recorded in recent years have been severely affecting the hydrologic and physical regimes of river systems. These changes have a direct impact on river discharge and runoff, some of which are occurred rapidly in the past two decades. Here, we present a quantitative analysis on the effects of changes in surface turbidity at coastal river mouths using diffuse attenuation coefficient at 490 nm (Kd490) as a proxy of turbidity for six major Indian peninsular rivers. The time series (2000-2022) trends of Kd490 obtained from Moderate Resolution Imaging Spectrometer (MODIS) images shows a significant decreasing trend in Kd values (p < 0.001) at the mouths of the Narmada, Tapti, Cauvery, Krishna, Godavari, and Mahanadi rivers. This is despite an increased rainfall trend observed for the six studied river basins which can likely intensifies the surface runoff and deliver more sediments, suggesting that other factors such as land use changes and increased number of dam constructions are primarily responsible for the decreased sediment load from rivers to coastal mouths.

2.
Medicine (Baltimore) ; 97(20): e10645, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29768330

RESUMEN

Osteoporosis or osteopenia is a common complication in patients with cirrhosis, but little is known about the risk factors for the occurrence of osteoporosis.Patients with liver cirrhosis due to chronic virus infection and alcoholic abuse were enrolled. Bone mineral density (BMD) was determined using dual-energy x-ray absorptiometry (DXA). Osteoporosis was diagnosed according to WHO criteria. The severity of liver stiffness was measured by Fibroscan. Demographic data, such as age, gender, weight, height, and body mass index (BMI), were collected. Logistic regression analysis was used to recognize the risk factors of osteoporosis in patients with cirrhosis.A total of 446 patients were included in this study: 217 had liver cirrhosis (male, 74.2%; mean age, 57.2 ±â€Š10.27) and 229 were matched controls (male, 69%, mean age, 56.69 ±â€Š9.37). Osteoporosis was found in 44 patients (44/217, 20.3%). The spine and hip BMD in cirrhotic patients were significantly lower than that in controls. When the cirrhotic and control subjects were stratified by age, gender, and BMI, the significant difference was also observed in women patients, patients older than 60, and patients with BMI < 18. Multivariate analysis showed that the older age [odds ratio (OR) = 1.78, P = .046], lower BMI (OR = 0.63, P = .049), greater fibroscan score (OR = 1.15, P = .009), and liver cirrhosis induced by alcohol liver disease (OR = 3.42, P < .001) were independently associated with osteoporosis in cirrhotic patients.Osteoporosis occurred in about one-fifth of patients with liver cirrhosis, which was associated with age, BMI, Fibroscan score, and alcohol liver disease related liver cirrhosis.


Asunto(s)
Enfermedades Óseas Metabólicas/etiología , Diagnóstico por Imagen de Elasticidad/métodos , Cirrosis Hepática/complicaciones , Osteoporosis/etiología , Absorciometría de Fotón , Adulto , Anciano , Densidad Ósea , Enfermedades Óseas Metabólicas/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico por imagen , Factores de Riesgo , Columna Vertebral/patología
3.
Med Sci Monit ; 23: 4132-4140, 2017 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-28844074

RESUMEN

BACKGROUND Leptocarpin (LTC) has drawn much attention for suppressing tumor growth or reducing inflammation. However, the effect of LTC on osteosarcoma has rarely been reported. Our object was to determine whether LTC suppresses MG63 cell proliferation, migration, and invasion, and whether type-1 insulin-like growth factor receptor (IGF-1R) is one of the targets in LTC suppressing osteosarcoma. MATERIAL AND METHODS Cytotoxicity of LTC was performed by use of a cell-counting kit-8 (CCK-8). RNA interference (RNAi) or pEABE-bleo IGF-1R plasmid were used for silencing or overexpressing IGF-1R, Western blot (WB) analysis was used for IGF-1R expression, CCK-8 for proliferation, and transwell assay for migration and invasion. RESULTS LTC (23.533 µM) treatment for 48 h was taken as the 50% inhibiting concentration (IC50), which significantly (P<0.05) suppressed MG63 cells proliferation, migration, and invasion. LTC (IC50) obviously inhibited IGF-1R expression in MG63 cells, with similar effect to small interfering RNA (siRNA), while pEABE-bleo IGF-1R transfection overexpressed IGF-1R. siRNA silencing IGF-1R suppressed MG63 cells proliferation, migration, and invasion, while pEABE-bleo IGF-1R transfection was significantly (P<0.05) promoted. With or without siRNA or pEABE-bleo IGF-1R transfection, LTC (IC50) suppressed MG63 cells proliferation, migration, and invasion. The effect of LTC (IC50) combined with siRNA on suppressing MG63 cells proliferation, migration, and invasion was more obvious, while the effect of LTC (IC50) combined with pEABE-bleo IGF-1R transfection was less significant (P<0.05). CONCLUSIONS LTC suppressed osteosarcoma proliferation, migration, and invasion by inhibiting IGF-1R expression. IGF-1R is one of the targets in LTC suppressing osteosarcoma.


Asunto(s)
Neoplasias Óseas/tratamiento farmacológico , Osteosarcoma/tratamiento farmacológico , Receptores de Somatomedina/antagonistas & inhibidores , Sesquiterpenos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Osteosarcoma/genética , Osteosarcoma/metabolismo , Osteosarcoma/patología , Interferencia de ARN , ARN Interferente Pequeño/genética , Receptor IGF Tipo 1 , Receptores de Somatomedina/metabolismo , Transducción de Señal
4.
Appl Opt ; 54(20): 6367-76, 2015 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-26193416

RESUMEN

Suspended sediments in water bodies are classified into organic and inorganic matter and have been investigated by remote-sensing technology for years. Focusing on inorganic matter, however, detailed information such as the grain size of this matter has not been provided yet. In this study, we present a new solution for estimating inorganic suspended sediments' size distribution in highly complex Case 2 waters by using a simple spectrometer sensor rather than a backscattering sensor. An experiment was carried out in the Pearl River Estuary (PRE) in the dry season to collect the remote-sensing reflectance (Rrs) and particle size distribution (PSD) of inorganic suspended sediments. Based on Mie theory, PSDs in the PRE waters were retrieved by Rrs, colored dissolved organic matter, and phytoplankton. The retrieved median diameters in 12 stations show good agreement with those of laboratory analysis at root mean square error of 2.604 µm (27.63%), bias of 1.924 µm (20.42%), and mean absolute error of 2.298 µm (24.37%). The retrieved PSDs and previous PSDs were compared, and the features of PSDs in the PRE waters were concluded.

5.
Mar Pollut Bull ; 54(8): 1267-72, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17537463

RESUMEN

In this paper, a method of assessing water quality from satellite data is introduced. The composite pollution index (CPI) was calculated from measured chemical oxygen demand (COD) and nutrient concentration. The relationships between CPI and 240 band combinations of SeaWiFS water-leaving radiance were analyzed and the optimal band combination for estimating CPI was chosen from the 240 band combinations. An algorithm for retrieval of CPI was developed using the optimal band combination, (L(443)xL(510))/(L(412)+L(490)). The CPI was estimated from atmospherically corrected SeaWiFS data by employing the algorithm. Furthermore, the CPI value range for each water quality level was determined based on data obtained from 850 samples taken in the Pearl River Estuary. The remotely sensed CPIs were then transferred to water quality levels and appropriate maps were derived. The remotely sensed water quality level maps displayed a similar distribution of levels based on in situ investigation issued by the State Ocean Administration, China. This study demonstrates that remote sensing can play an important role in water quality assessment.


Asunto(s)
Monitoreo del Ambiente/métodos , Agua de Mar/análisis , Contaminantes Químicos del Agua/análisis , Algoritmos , China , Fertilizantes/análisis , Oxígeno/análisis , Oxígeno/metabolismo , Ríos/química , Nave Espacial
6.
Artículo en Inglés | MEDLINE | ID: mdl-12929815

RESUMEN

This article introduces a practical method to investigate thermal pollution in coastal water from satellite data. The intensity and distribution areas of thermal pollution by the heated effluent discharge from the nuclear power plant on Daya Bay, southern China were investigated by using Landsat-5 Thematic Mapper (TM) thermal band data from 1994 to 2001. A local algorithm was developed, based on sea-truth data of water surface temperature measured when the satellite passed over the study area. The local algorithm was then applied to estimate water temperature from TM data. It shows that the remote sensing technique provides an effective means to quantitatively monitor the intensity of thermal pollution and to retrieve a very detailed distribution pattern of thermal pollution in coastal waters. The remotely-sensed results of the thermal pollution can be used for environmental management of coastal waters.


Asunto(s)
Monitoreo del Ambiente/métodos , Centrales Eléctricas , Temperatura , Contaminantes del Agua/análisis , Algoritmos , Nave Espacial , Eliminación de Residuos Líquidos
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