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1.
Environ Monit Assess ; 195(3): 392, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781573

RESUMO

Climate change has caused medicinal plants to become increasingly endangered. Descurainia sophia (flixweed) is at risk of extinction in Fars Province, Iran, due to climate change and modifications of land use. Flixweed is highly valuable because of its medicinal properties. The conservation of this species using habitat suitability modeling seems necessary. In this research, the geographical locations of D. sophia's distribution in southern Iran were recorded and mapped using ArcGIS 10.2.2. Then, ten important variables affecting the growth of D. sophia medicinal plants were identified and prepared as thematic layers. These variables were, namely, "elevation," "slope degree," "slope aspect," "soil physical characteristics (sand, silt, and clay percentage)," "soil chemical properties (EC and pH)," "annual mean rainfall," "annual mean temperature," "distance to roads," "distance to rivers," and "plan curvature." In this study, three bivariate models, including the "index-of-entropy (IofE)," "frequency ratio (FR)," and "weight of evidence (WofE)," were used for mapping the habitat suitability of D. sophia. Moreover, the ROC curve and AUC index were used for evaluating the accuracy of the models. Based on the results, the IofE model ("AUC": 0.93) was the most accurate, while the FR ("AUC": 0.92) and WofE ("AUC": 0.90) models ranked second and third, respectively. The models in this study can be applied as tools for the protection of endangered medicinal plants. Furthermore, the map could assist planners, decision-makers, and engineers in extending study areas. By determining the habitat maps of medicinal plants, their extinction can be prevented. Such maps can also assist in the propagation of medicinal plants.


Assuntos
Plantas Medicinais , Monitoramento Ambiental/métodos , Ecossistema , Solo , Irã (Geográfico)
2.
J Environ Manage ; 280: 111858, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360552

RESUMO

Flash flood is one of the most dangerous hydrologic and natural phenomena and is considered as the top ranking of such events among various natural disasters due to their fast onset characteristics and the proportion of individual fatalities. Mapping the probability of flash flood events remains challenges because of its complexity and rapid onset of precipitation. Thus, this study aims to propose a state-of-the-art data mining approach based on a hybrid equilibrium optimized SysFor, namely, the HE-SysFor model, for spatial prediction of flash floods. A tropical storm region located in the Northwest areas of Vietnam is selected as a case study. For this purpose, 1866 flash-flooded locations and ten indicators were used. The results show that the proposed HE-SysFor model yielded the highest predictive performance (total accuracy = 93.8%, Kappa index = 0.875, F1-score = 0.939, and AUC = 0.975) and produced the better performance than those of the C4.5 decision tree (C4.5), the radial basis function-based support vector machine (SVM-RBF), the logistic regression (LReg), and deep learning neural network (DeepLNN) models in both the training and the testing phases. Among the ten indicators, elevation, slope, and land cover are the most important. It is concluded that the proposed model provides an alternative tool and may help for effectively monitoring flash floods in tropical areas and robust policies for decision making in mitigating the flash flood impacts.


Assuntos
Tempestades Ciclônicas , Inundações , Mineração de Dados , Rios , Vietnã
3.
Clin Case Rep ; 12(5): e8879, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38721560

RESUMO

Key Clinical Message: Placenta previa, accompanied by placenta percreta, which involves invasion of the bladder, presents a significant risk of excessive bleeding during and after delivery. This case highlights that prophylactic embolization, conservative surgery, and careful monitoring offer an effective approach to avoid hysterectomy in cases of placenta percreta with adjacent organ involvement. Abstract: Placenta previa complicated by placenta percreta is associated with a high risk of massive intra and post-partum hemorrhage. We present a case of a 35-year-old woman (G2 P1) who was referred to the Akbar-Abadi hospital at 13 weeks of gestation. Color Doppler ultrasound indicated complete placenta previa-percreta with bladder invasion. After induction of fetal demise, bilateral uterine and bladder artery endovascular embolization was conducted for the patient. After 48 h, under ultrasound guidance, surgical resection of residual percreta tissue was conducted as much as possible. Eight weeks later, a follow-up sonography showed the minimum residual placenta tissue and she regained menstrual cycles after 2 months. This case indicated that the combination of prophylactic embolization, conservative surgical management with placenta left in situ, and follow-up with serial color Doppler monitoring, is an optimum method to avoid hysterectomy in placenta percreta patient with adjacent organ invasion.

4.
Environ Sci Pollut Res Int ; 30(44): 99380-99398, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37612559

RESUMO

Ensemble learning techniques have shown promise in improving the accuracy of landslide models by combining multiple models to achieve better predictive performance. In this study, several ensemble methods (Dagging, Bagging, and Decorate) and a radial basis function classifier (RBFC) were combined to predict landslide susceptibility in the Trung Khanh district of the Cao Bang Province, Vietnam. The ensemble models were developed using a geospatial database containing 45 historical landslides (1074 points) and thirteen influencing variables characterizing the topography, geology, land use/cover, and human activities of the study area. The performance of the models was evaluated based on the area under the receiver operating characteristic curve (AUC) and several other performance metrics, including positive predictive value (PPV), negative predictive value (NPV), sensitivity (SST), specificity (SPF), accuracy (ACC), and root mean square error (RMSE). The Bagging-RBFC model with PPV = 86%, NPV = 95%, SST = 95%, SPF = 87%, ACC = 91%, RMSE = 0.297, and AUC = 98% was found to be the most accurate model for the prediction of landslide susceptibility, followed by the Dagging-RBFC, Decorate-RBFC, and single RBFC models. The study demonstrates the efficacy of ensemble learning techniques in developing reliable landslide predictive models, which can ultimately save lives and reduce infrastructure damage in landslide-prone regions worldwide.


Assuntos
Deslizamentos de Terra , Humanos , Bases de Dados Factuais , Geologia , Valor Preditivo dos Testes , Benchmarking
5.
Sci Rep ; 10(1): 3203, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081935

RESUMO

The aim of the current study was to suggest a multi-hazard probability assessment in Fars Province, Shiraz City, and its four strategic watersheds. At first, we construct maps depicting the most effective factors on floods (12 factors), forest fires (10 factors), and landslides (10 factors), and used the Boruta algorithm to prioritize the impact of each respective factor on the occurrence of each hazard. Subsequently, flood, landslides, and forest fire susceptibility maps prepared using a Random Forest (RF) model in the R statistical software. Results indicate that 42.83% of the study area are not susceptible to any hazards, while 2.67% of the area is at risk of all three hazards. The results of the multi-hazard map in Shiraz City indicate that 25% of Shiraz city is very susceptible to flooding, while 16% is very susceptible to landslide occurrences. For four strategic watersheds, it is notable that in the Dorodzan Watershed, landslides and floods are the most important hazards; whereas, flood occurrences cover the largest area of the Maharlou Watershed. In contrast, the Tashk-Bakhtegan Watershed is so sensible to floods and landslides, respectively. Finally, in the Ghareaghaj Watershed, forest fire ranks as the strongest hazard, followed by floods. The validation results indicate an AUC of 0.834, 0.939, and 0.943 for the flood, landslide, and forest fire susceptibility maps, respectively. Also, other accuracy measures including, specificity, sensitivity, TSS, CCI, and Gini coefficient confirmed results of the AUC values. These results allow us to forecast the spatial behavior of such multi-hazard events, and researchers and stakeholders alike can apply them to evaluate hazards under various mitigation scenarios.

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