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1.
Environ Sci Pollut Res Int ; 30(50): 109021-109040, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37759055

RESUMO

Seawater intrusion is a growing concern for coastal regions in Bangladesh. Overexploitation of groundwater, low rainfall, a high rate of evaporation, rising sea level, cyclones, storm surges, and shrimp cultivation are the causes of seawater intrusion that polluted the groundwater near the coastal area. High values of EC, TDS, Na+, and Cl- ions in groundwater indicate the seawater intrusion. Piper's Trilinear and Durov diagrams of groundwater indicated that most gathered groundwater show predominantly Na-Cl-type of water. Based on the USSL diagram, it is observed that the salinity of the study area is medium to high and the alkalinity is medium to very high. Also, in view of the Wilcox outline, most of the samples in the area of interest are permissible to doubtful, and doubtful to unsuitable. Chloride is moderately correlated with Na+ (R2 = 0.590) and poorly correlated with (HCO3- + CO32-) (R2 = 0.128), which indicates seawater intrusion. According to a comparison of the levels of Fe and Mn in the groundwater of the study area with those recommended by the World Health Organization (WHO) and Department of the Environment (DOE), twenty-two out of thirty-one samples exceed the acceptable limit for Fe and thirty out of thirty-one samples fall within the acceptable limit for Mn. The calculated water quality index reveals that most samples are of low drinking water quality. The research area's poor water type is found in the north-central and southern parts. The WQI geographic variation map reveals that the study's water has a WQI of more than 100, making it unsuitable for consumption. The final seawater intrusion vulnerability map clearly identifies the moderate to highly vulnerable zone of the study area using DRASTIC index parameters. DRASTIC index parameters revealed that some portions of the northwestern part of the sample area show a moderately vulnerable zone. And the rest of the sampling area indicates the highly vulnerable zone.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Bangladesh , Qualidade da Água , Água do Mar , Íons , Poluentes Químicos da Água/análise
2.
Heliyon ; 9(3): e13593, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36873528

RESUMO

Highland bamboo (Oldeania alpina) is fast growing perennial plant that occurs as small holder plantation and naturally in the highlands of Ethiopia with a wide range of values and uses. This study assessed environmental conditions where the species grows, and related the sites-suitability information to other potential regions in Ethiopia. Field survey was conducted to Oldeania alpina growing areas in Ethiopia. Data were collected on dendrometric and environmental variables from field plots of 400 m2 of bamboo stands in three replications in each of the study districts in the regions. Consultations were also held with key informants, women, youth and elder focus group discussants on the common uses and production constraints of the species. The study identified wider uses of the species from being raw material for household utensils, furniture, fencing to building local houses in Ethiopia. Observations indicate that Oldeania alpina grows in the south, south-western, central and north-western highlands of Ethiopia at altitudes ranging from 2200 to 4000 m.a.s.l. It grows rapidly, where after planting from offset, starts to yield useable culm within three to four years. The species growing sites characteristics in the present study indicated that it's well performing in the altitudinal range between 2387 and 2979 m.a.s.l. We recommend promoting highland bamboo in Ethiopia for better culm yield on sites with elevation from 2300 up to 3500 m.a.s.l with mean annual rainfall >1200 mm, temperature varying from min. 6 °C to max. 30 °C and slope from 0 to 60% to attain optimum growth across the country.

3.
Ann Math Artif Intell ; : 1-20, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36193340

RESUMO

Road network studies attracted unprecedented and overwhelming interest in recent years due to the clear relationship between human existence and city evolution. Current studies cover many aspects of a road network, for example, road feature extraction from video/image data, road map generalisation, traffic simulation, optimisation of optimal route finding problems, and traffic state prediction. However, analysing road networks as a complex graph is a field to explore. This study presents comparative studies on the Porto, in Portugal, road network sections, mainly of Matosinhos, Paranhos, and Maia municipalities, regarding degree distributions, clustering coefficients, centrality measures, connected components, k-nearest neighbours, and shortest paths. Further insights into the networks took into account the community structures, page rank, and small-world analysis. The results show that the information exchange efficiency of Matosinhos is 0.8, which is 10 and 12.8% more significant than that of the Maia and Paranhos networks, respectively. Other findings stated are: (1) the studied road networks are very accessible and densely linked; (2) they are small-world in nature, with an average length of the shortest pathways between any two roads of 29.17 units, which as found in the scenario of the Maia road network; and (3) the most critical intersections of the studied network are 'Avenida da Boavista, 4100-119 Porto (latitude: 41.157944, longitude: - 8.629105)', and 'Autoestrada do Norte, Porto (latitude: 41.1687869, longitude: - 8.6400656)', based on the analysis of centrality measures.

4.
Sensors (Basel) ; 21(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34833794

RESUMO

With the rapid growth and development of cities, Intelligent Traffic Management and Control (ITMC) is becoming a fundamental component to address the challenges of modern urban traffic management, where a wide range of daily problems need to be addressed in a prompt and expedited manner. Issues such as unpredictable traffic dynamics, resource constraints, and abnormal events pose difficulties to city managers. ITMC aims to increase the efficiency of traffic management by minimizing the odds of traffic problems, by providing real-time traffic state forecasts to better schedule the intersection signal controls. Reliable implementations of ITMC improve the safety of inhabitants and the quality of life, leading to economic growth. In recent years, researchers have proposed different solutions to address specific problems concerning traffic management, ranging from image-processing and deep-learning techniques to forecasting the traffic state and deriving policies to control intersection signals. This review article studies the primary public datasets helpful in developing models to address the identified problems, complemented with a deep analysis of the works related to traffic state forecast and intersection-signal-control models. Our analysis found that deep-learning-based approaches for short-term traffic state forecast and multi-intersection signal control showed reasonable results, but lacked robustness for unusual scenarios, particularly during oversaturated situations, which can be resolved by explicitly addressing these cases, potentially leading to significant improvements of the systems overall. However, there is arguably a long path until these models can be used safely and effectively in real-world scenarios.


Assuntos
Aprendizado Profundo , Previsões , Processamento de Imagem Assistida por Computador , Qualidade de Vida
5.
Pak J Pharm Sci ; 28(3): 855-61, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26004717

RESUMO

Bi-layer tablets of tramadol hydrochloride were prepared by direct compression technique. Each tablet contains an instant release layer with a sustained release layer. The instant release layer was found to release the initial dose immediately within minutes. The instant release layer was combined with sustained release matrix made of varying quantity of Methocel K4M, Methocel K15MCR and Carbomer 974P. Bi-layer tablets were evaluated for various physical tests including weight variation, thickness and diameter, hardness and percent friability. Drug release from bi-layer tablet was studied in acidic medium and buffer medium for two and six hours respectively. Sustained release of tramadol hydrochloride was observed with a controlled fashion that was characteristic to the type and extent of polymer used. % Drug release from eight-hour dissolution study was fitted with several kinetic models. Mean dissolution time (MDT) and fractional dissolution values (T25%, T50% and T80%) were also calculated as well, to compare the retarding ability of the polymers. Methocel K15MCR was found to be the most effective in rate retardation of freely water-soluble tramadol hydrochloride compared to Methocel K4M and Capbomer 974P, when incorporated at equal ratio in the formulation.


Assuntos
Resinas Acrílicas/farmacocinética , Analgésicos Opioides/farmacocinética , Composição de Medicamentos , Metilcelulose/farmacocinética , Comprimidos/farmacocinética , Tramadol/farmacocinética , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Dureza , Comprimidos/química
6.
Pak J Pharm Sci ; 22(2): 155-61, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19339225

RESUMO

This investigation describes the preparation and in vitro evaluation of gastroretentive floating tablet of theophylline. Two hydrophilic cellulose derivatives, Methocel K100M and Methocel K15MCR were evaluated for their gel forming and release controlling properties. Sodium bicarbonate and citric acid were incorporated as gas generating agents. The effects of soluble components (sodium bicarbonate and citric acid), gel forming agents and amount variation of theophylline on drug release profile and floating properties were investigated. Tablets were prepared by direct compression technique. Formulations were evaluated for in vitro buoyancy and drug release study was evaluated for eight hours using USP XXII paddle-type dissolution apparatus using 0.1N HCl as dissolution medium. The release mechanisms were explored and explained with zero order, first order, Higuchi and Korsmeyer equations. The release rate, extent and mechanisms were found to be governed by polymer and floating agent content. The content of active ingredient was also a vital factor in controlling drug release pattern. It was found that polymer content and amount of floating agent significantly affected the mean dissolution time, percentage drug release after 8 hours, release rate constant and diffusion exponent.


Assuntos
Portadores de Fármacos , Metilcelulose/química , Teofilina/química , Química Farmacêutica , Ácido Cítrico/química , Preparações de Ação Retardada , Difusão , Composição de Medicamentos , Mucosa Gástrica/metabolismo , Géis , Cinética , Modelos Químicos , Bicarbonato de Sódio/química , Solubilidade , Comprimidos , Teofilina/metabolismo
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