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1.
Environ Res ; 255: 119208, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38782341

RESUMO

North China type coalfield are gradually mining deep, and the mixing of groundwater is intensified. Hydrogen and oxygen isotopes are important elements for tracing groundwater movement. The fractionation response mechanism under mining conditions is not clear. In this paper, combined with numerical simulation, MixSIAR isotope mixing model and other methods, according to the δD, δ18O and hydrochemical information of various water bodies, the impact of coal mining on hydrogen and oxygen isotope fractionation is analyzed from multiple perspectives. The results show that summer soil water is the main source of recharge for limestone water, accounting for 30.7%-41.5%, and the Zhan River is the main source of recharge for limestone water. Before groundwater recharge, evaporation leads to the increase of δ18O in surface water by 0.31‰-5.58‰, water loss by 1.81%-28.00%, the increase of δ18O in soil water by 0.47‰-6.33‰, and water loss by 2.74%-35.80%. Compared with the coal mining layer, the degree of hydrogen and oxygen isotope drift and water-rock interaction in the coal mine stopping layer are significantly improved. The results of numerical simulation show that the pumping activity reduces the 18O concentration in the mining layer. The ion ratio is used as a new variable to eliminate the influence of water-rock interaction when calculating the mixing ratio. The results show that the limestone water is in a state of receiving external recharge, and mixing effect increases the δ18O in limestone water by 0.86‰ on average, and the δD increases by 0.72‰ on average. The research results explain the controlled process of hydrogen and oxygen isotope fractionation under mining conditions, which is of great significance to coal mine safety production.


Assuntos
Carbonato de Cálcio , Água Subterrânea , Isótopos de Oxigênio , Isótopos de Oxigênio/análise , Água Subterrânea/química , Água Subterrânea/análise , Carbonato de Cálcio/química , Carbonato de Cálcio/análise , Minas de Carvão , Deutério/análise , Fracionamento Químico , Mineração , Movimentos da Água , Monitoramento Ambiental/métodos , China , Hidrogênio/análise , Hidrogênio/química
2.
China Tropical Medicine ; (12): 319-2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-979638

RESUMO

@#Abstract: Objective To investigate the clinical characteristics and incidence of Brucella encephalitis and meningitis in children. Methods We report the clinical data of a child with Brucella melitensis meningitis in children, and summarize the incidence, diagnosis methods and treatment of Brucella encephalitis or meningitis in children, taking into account the relevant domestic and foreign literature from January 2014 to December 2020. Results A 4-year-old girl was admitted to the hospital with status epilepticus on March 15, 2021 because of interrupted right limb numbness for 16 hours and convulsions for 2 hours. She had 2 non-febrile convulsions three months before admission and was diagnosed with epilepsy. This incident was acute, accompanied by low fever, with epilepsy as the main manifestation. Cerebrospinal fluid test suggested central nervous system infection, but the nature of infection could not be determined by routine and biochemistry of cerebrospinal fluid.The cerebrospinal fluid next generation sequencing confirmed that the pathogen of the infection was B. melitensis, which was further verified by the peripheral blood antibody test. After effective antibiotics combined with a full course of treatment, the patient recovered after six months of treatment. A total of 60 articles were retrieved in the database, including 29 in Chinese. During this period, a total of 7 cases of brucellosis in children with nervous system involvement were reported, one of which was a case report, and the other 6 cases were mentioned in the comprehensive analysis of children with brucellosis. Conclusions Brucella encephalitis or meningitis in children has a low incidence and various clinical features, which are easy to be misdiagnosed or missed.

3.
IEEE Trans Vis Comput Graph ; 22(2): 1115-26, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26731455

RESUMO

Manual editing of a metro map is essential because many aesthetic and readability demands in map generation cannot be achieved by using a fully automatic method. In addition, a metro map should be updated when new metro lines are developed in a city. Considering that manually designing a metro map is time-consuming and requires expert skills, we present an interactive editing system that considers human knowledge and adjusts the layout to make it consistent with user expectations. In other words, only a few stations are controlled and the remaining stations are relocated by our system. Our system supports both curvilinear and octilinear layouts when creating metro maps. It solves an optimization problem, in which even spaces, route straightness, and maximum included angles at junctions are considered to obtain a curvilinear result. The system then rotates each edge to extend either vertically, horizontally, or diagonally while approximating the station positions provided by users to generate an octilinear layout. Experimental results, quantitative and qualitative evaluations, and user studies show that our editing system is easy to use and allows even non-professionals to design a metro map.

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