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1.
Natl Sci Rev ; 10(6): nwad069, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37181085

RESUMO

With the aid of the newly developed 'Sunway' heterogeneous-architecture supercomputer, which has world-leading HPC (high-performance computer) capability, a series of high-resolution coupled Earth system models (SW-HRESMs) with up to 5 km of atmosphere and 3 km of ocean have been developed. These models can meet the needs of multiscale interaction studies with different computational costs. Here we describe the progress of SW-HRESMs development, with an overview of the major advancements made by the international Earth science community in HR-ESMs. We also show the preliminary results of SW-HRESMs with regard to capturing major weather-climate extremes in the atmosphere and ocean, stressing the importance of permitted clouds and ocean submesoscale eddies in modeling tropical cyclones and eddy-mean flow interactions, and paving the way for further model development to resolve finer scales with even higher resolution and more realistic physics. Finally, in addition to increasing model resolution, the development procedure for a non-hydrostatic cloud and ocean submesoscale resolved ESM is discussed, laying out the major scientific directions of such a huge modeling advancement.

2.
Environ Sci Pollut Res Int ; 29(36): 54467-54475, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35301632

RESUMO

Current research on prothioconazole (PTC), a broad-spectrum triazole fungicide, mainly focuses on its efficacy and residues; only a few studies have been assessing its toxicological effects. Using acute and chronic toxicity tests, we assessed the effects of PTC and its metabolite prothioconazole-desthio (PTCd) on the inhibition of the activity, growth, and reproduction of Daphnia magna. A dose-response relationship was established to determine sensitive biological indicators. In the acute and chronic toxicity tests, the 48-h EC50 (concentration for 50% of the maximal effect) of PTC and PTCd for D. magna were 2.82 and 5.19 mg/L and 0.0807 and 0.132 mg/L, respectively; in the latter test, PTC was 1.64 times more toxic than PTCd. Acute-to-chronic toxicity ratios were calculated using chronic toxicity data; the ratios were 227 and 27.5 for PTC and PTCd, respectively. Our results indicate that both PTC and PTCd affect the growth and reproduction of D. magna and that the toxicity of PTC is greater than that of PTCd. In conclusion, the metabolites of PTD are toxic to D. magna at certain concentrations, and their environmental risks should not be neglected.


Assuntos
Fungicidas Industriais , Poluentes Químicos da Água , Animais , Daphnia , Fungicidas Industriais/química , Reprodução , Testes de Toxicidade Crônica , Triazóis/análise , Poluentes Químicos da Água/toxicidade
3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-904725

RESUMO

@#Objective    To investigate the feasibility of using magnetic beads to locate small pulmonary nodules. Methods    Twelve rabbits were randomly divided into two groups, 6 in each group. One group underwent thoracotomy after anesthesia and the other group underwent percutaneous puncture under the guidance of X-ray. One and two cylindrical tracer magnets (magnetic beads) with a diameter of 1 mm and a height of 3 mm were injected adjacent to the imaginary pulmonary nodules in left lung in each group. The magnetic beads beside the imaginary nodules were attracted by a pursuit magnet with a diameter of 9 mm and a height of 19 mm. The effectiveness of localization by magnetic beads were determined by attraction between tracer and pursuit magnets. Results    All processes were uneven in 12 rabbits. There was micro hemorrhage and no hematoma in the lung tissue at the injection site of the magnetic beads. When tracked with the pursuit magnets, there was one bead divorce in cases that one bead was injected, but no migration or divorce of the magnetic beads in cases that two magnetic beads were simultaneously injected to localize the small pulmonary nodules. Conclusion    The feasibility of using magnetic beads to locate small pulmonary nodules has been  preliminarily verified.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-788955

RESUMO

Objective To investigate the epidemical characteristics and analyze the incidence trend of novel coronavirus pneumonia (NCP) in Shanghai. Methods The epidemical data on NCP in Shanghai from January 20 to February 3, 2020 were collected for epidemiological descriptive analysis. Results The number of cumulative confirmed and suspected cases increased first and then decreased from January 20 to February 3, with the peak date being January 30 and January 29 respectively. The day-on-day growth rate of the suspected cases and the cumulative confirmed cases declined after January 27. Among the confirmed cases, the proportion of the exposure history of relevant confirmed cases was on the rise. The total number of confirmed cases of the resident population exceeded that of the population from other places to Shanghai, and Pudong new area had the largest number of confirmed cases. Conclusion The incidence of NCP showed a slowdown trend in shanghai, but it also faces the pressure of the peak of population returning to city, which should be paid enough attention to.

5.
J Hazard Mater ; 304: 409-16, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26595900

RESUMO

The current research investigated a process combining leaching, purification and membrane electrodeposition to recover tin from the metal components of WPCBs. Experimental results showed that with a solid liquid ratio of 1:4, applying 1.1 times of stoichiometric SnCl4 dosage and HCl concentration of 3.5-4.0 mol/L at a temperature of 60-90°C, 99% of tin can be leached from the metal components of WPCBs. The suitable purification conditions were obtained in the temperature range of 30-45°C with the addition of 1.3-1.4 times of the stoichiometric quantity of tin metal and stirring for a period of 1-2h; followed by adding 1.3 times of the stoichiometric quantity of Na2S for sulfide precipitation about 20-30 min at room temperature. The purified solution was subjected to membrane electrowinning for tin electrodeposition. Under the condition of catholyte Sn(2+) 60 g/L, HCl 3 mol/L and NaCl 20 g/L, current density 200 A/m(2) and temperature 35°C, a compact and smooth cathode tin layer can be obtained. The obtained cathode tin purity exceeded 99% and the electric consumption was less than 1200 kW h/t. The resultant SnCl4 solution generated in anode compartment can be reused as leaching agent for leaching tin again.

6.
International Eye Science ; (12): 1301-1302, 2015.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-639283

RESUMO

AlM:To observe the changes of binocular vision in V-pattern exotropia children before and after surgical correction, and the effect of training in reconstructing the binocular vision after surgical corrections.METHODS: Sixty V-pattern exotropia children were enrolled in this study and were divided into three groups according to their age:group A (4~6 years old), group B (7~9 years old), and group C (10~12 years old), 20 cases for each group. Patients received routine refraction and ophthalmic examinations. Distance and near deviation were measured by prism-covering method and synoptophore. The simultaneous perception and fusion were examined with a synoptophore, and the stereacuity was measured with stereograms ( Titmus) . The children who didn’t reconstruct binocular vision function 1wk after surgery received binocular vision training. The data were recorded before and 1 , 2, 4, and 8wk after surgery. RESULTS: Binocular vision significantly improved among the children after surgery in group A and B ( P0. 05). CONCLUSlON: V - pattern exotropia children can benefit from early surgical correction and training after surgery in reconstruct binocular vision.

7.
Environ Sci Technol ; 48(9): 5101-7, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24730751

RESUMO

Hydrous manganese oxide (HMO) is generally negatively charged at circumneutral pH and cannot effectively remove anionic pollutants such as phosphate. Here we proposed a new strategy to enhance HMO-mediated phosphate removal by immobilizing nano-HMO within a polystyrene anion exchanger (NS). The resultant nanocomposite HMO@NS exhibited substantially enhanced phosphate removal in the presence of sulfate, chloride, and nitrate at greater levels. This is mainly attributed to the pHpzc shift from 6.2 for the bulky HMO to 10.5 for the capsulated HMO nanoparticles, where HMO nanoparticles are positively charged at neutral pH. The ammonium groups of NS also favor phosphate adsorption through the Donnan effect. Cyclic column adsorption experiment indicated that the fresh HMO@NS could treat 460 bed volumes (BV) of a synthetic influent (from the initial concentration of 2 mg P[PO4(3-)]/L to 0.5 mg P[PO4(3-)]/L), while only 80 BV for NS. After the first time of regeneration by NaOH-NaCl solution, the capacity of HMO@NS was lowered to ∼ 300 BV and then kept constant for the subsequent 5 runs, implying the presence of both the reversible and irreversible adsorption sites of nano-HMO. Additional column adsorption feeding with a real bioeffluent further validated great potential of HMO@NS in advanced wastewater treatment. This study may provide an alternative approach to expand the usability of other metal oxides in water treatment.


Assuntos
Compostos de Manganês/química , Óxidos/química , Fosfatos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Nanopartículas , Espectrofotometria Ultravioleta
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-446598

RESUMO

BACKGROUND:Schwann cells are important celllines in the process of repairing peripheral nerve injury, and human amniotic homogenate supernatant is shown to secrete a variety of cytokines, which could promote the proliferation of Schwann cells. OBJECTIVE:To investigate the effect of different concentrations of human amniotic homogenate supernatant on the proliferation of rat Schwann cell96. METHODS:Schwann cell96 was cultured with high-glucose DMEM containing 20%fetal bovine serum, and the second generation of Schwann cell96 was applied for experiments. The cultured cells were divided into five groups according to different volume fractions of human amniotic homogenate supernatant (0%, 10%, 15%, 20%, 25%) in the medium. RESULTS AND CONCLUSION:The total protein concentration of human amniotic homogenate supernatant was 675μg/mL, in which the concentration of epidermal growth factor, basic fibroblast growth factor and vascular endothelial growth factor were respectively (470.625±2.546), (4.121±0.026) and (0.172±0.002) ng/L. At 1-7 days, the cellproliferation rate of the 10%and 15%concentration groups was greater than that in 20%and 25%concentration groups (P0.05). Low concentrations (10%, 15%) of human amniotic homogenate supernatant promote the proliferation of Schwann cell96, while high concentrations (20%, 25%) of human amniotic homogenate supernatant inhibit cellproliferation.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-313709

RESUMO

<p><b>OBJECTIVE</b>To investigate the effect of short hairpin RNA (shRNA) targeting hypoxia-inducible factor-1 alpha (HIF-1 alpha) on the human breast carcinoma MCF-7 cell line.</p><p><b>METHODS</b>The hypoxia environment was achieved by treating cells with cobalt chloride. The shRNA eukaryotic expression vector targeting HIF-1 alpha was constructed, and transfected into MCF-7 cells through lipofectamine 2000. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to study the expression of vascular endothelial growth factor (VEGF). The mRNA and protein level of HIF-1 alpha were detected by real-time PCR and Western blot. Sub-G1 apoptotic population analysis, Annexin V/PI binding assay, and DNA ladder analysis were applied to investigate the cell apoptosis. The cell cycle was detected by flow cytometry.</p><p><b>RESULTS</b>The mRNA and protein level of HIF-1 alpha increased after exposure of MCF-7 cells to hypoxia (P < 0.01). However, apoptosis was lower in hypoxia compared with normoxia (P < 0.05). The HIF-1 level of MCF-7 transfected with HIF-1 alpha shRNA decreased approximately 91.63% (P < 0.01). When the cells were treated with or without apoptosis inducer Ara-C, the apoptosis of MCF-7 cells transfected with HIF-1 alpha shRNA increased by 1.75 times (P < 0.01) and 61. 31 times (P < 0.01), respectively. The expression of VEGF in MCF-7 cells transfected with HIF-1 alpha shRNA decreased 66.8% compared with untransfected cells (P < 0.05). Cell cycle progression was inhibited when the MCF-7 cells were transfected with HIF-1 alpha shRNA.</p><p><b>CONCLUSIONS</b>HIF-1 alpha plays an anti-apoptotic role in human breast carcinoma MCF-7 cell line. The shRNA we designed targeting HIF-1 alpha in MCF-7 can promote cell apoptosis, inhibit the expression of VEGF, and delay cell cycle progression.</p>


Assuntos
Feminino , Humanos , Apoptose , Neoplasias da Mama , Genética , Metabolismo , Patologia , Ciclo Celular , Linhagem Celular Tumoral , Regulação para Baixo , Subunidade alfa do Fator 1 Induzível por Hipóxia , Genética , Interferência de RNA , RNA Mensageiro , Genética , RNA Interferente Pequeno , Genética , Transfecção , Fator A de Crescimento do Endotélio Vascular , Metabolismo
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