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3.
Environ Res ; 214(Pt 1): 113786, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35798269

RESUMO

The increasing requirement and consumption of coal has resulted in a large accumulation of coal gangue. The reuse and recycling of coal gangue have become a high priority for sustainable development. A sustainable and efficient ceramsite adsorbent was prepared for copper ions adsorption by using coal gangue, coal fly ash, and copper slag as the main materials. The appropriate performance of the ceramsite could be obtained at a mixture of coal gangue, coal fly ash, and copper slag at a weight ratio of 3:4:1. The optimal sintering temperature and time were 1050 °C and 20 min, respectively. The main crystalline phases of ceramsite were quartz, mullite, and anorthite. Many micropores are connecting the interior on the surface of ceramsite under scanning electron microscope. The maximum copper ions adsorption capacity reached up to 20.6 mg/g at 303 K when pH and time were 5 and 1440 min, respectively. The adsorption kinetics and isotherm could be described by the pseudo-second-order model and Freundlich model, respectively. The adsorption mechanisms of Cu2+ with ceramsite were attributed to Cu(OH)2 precipitation formed on the alkaline surface of ceramsite and complexation reactions occurred between the O-containing groups (including C-O, Fe-O, and Si-O) from ceramsite and Cu2+. The prepared ceramsite may be also applied to other heavy metal wastewater treatments.


Assuntos
Resíduos Industriais , Poluentes Químicos da Água , Adsorção , Carvão Mineral , Cinza de Carvão , Misturas Complexas , Cobre , Íons , Cinética
4.
PLoS One ; 16(11): e0252149, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34793471

RESUMO

Estimating net primary productivity (NPP) is significant in global climate change research and carbon cycle. However, there are many uncertainties in different NPP modeling results and the process of NPP is challenging to model on the absence of data. In this study, we used meteorological data as input to simulate vegetation NPP through climate-based model, synthetic model and CASA model. Then, the results from three models were compared with MODIS NPP and observed data over China from 2000 to 2015. The statistics evaluation metrics (Relative Bias (RB), Pearson linear Correlation Coefficient (CC), Root Mean Square Error (RMSE), and Nash-Sutcliffe efficiency coefficient (NSE)) between simulated NPP and MODIS NPP were calculated. The results implied that the CASA-model performed better than the other two models in terms of RB, RMSE, NSE and CC whether on the national or the regional scale. It has a higher CC with 0.51 and a smaller RMSE with 111.96 g C·m-2·yr-1 in the whole country. The synthetic model and CASA-model has the same advantages at some regions, and there are lower RMSE in Southern China (86.35 g C·m-2·yr-1), Xinjiang (85.53 g C·m-2·yr-1) and Qinghai-Tibet Plateau (93.22 g C·m-2·yr-1). The climate-based model has widespread overestimation and large systematic errors, along with worse performances (NSEmax = 0.45) and other metric indexes unsatisfactory, especially Qinghai-Tibet Plateau with relatively lower accuracy because of the unavailable observation data. Overall, the CASA-model is much more ideal for estimating NPP all over China in the absence of data. This study provides a comprehensive intercomparison of different NPP-simulated models and can provide powerful help for researchers to select the appropriate NPP evaluation model.


Assuntos
Ciclo do Carbono , Mudança Climática , Monitoramento Ambiental , Modelos Teóricos , China , Ecossistema
5.
Artigo em Inglês | MEDLINE | ID: mdl-31740554

RESUMO

To understand the characterizations of azole resistance in Aspergillus fumigatus from potting soil samples in the hospital, a total of 58 samples were collected. Among 106 A. fumigatus samples obtained, 5 isolates from 4 soil samples located in the gerontology department were identified as azole-resistant A. fumigatus (ARAF). Four ARAF isolates harbored the TR34/L98H allele, and the other one had no mutation in the cyp51A gene. Among 174 A. fumigatus samples selected for genotyping, TRESPERG typing obtained a close discriminatory power (Simpson's index of diversity [DI], 0.9941; 95% confidence interval [CI], 0.9913 to 0.9968) compared with the short tandem repeat (STR) typing (DI, 0.9997; 95% CI, 0.9976 to 1.0000). Genotyping showed that the TR34/L98H isolates in the hospital had a close genetic relationship with ARAF isolates from China and many other countries. In conclusion, this study indicated the presence of ARAF in potting soil samples from the hospital, which might pose a risk of causing ARAF infection in patients.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Azóis/farmacologia , Farmacorresistência Fúngica/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Microbiologia do Solo , Alelos , Aspergillus fumigatus/genética , China , Infecção Hospitalar/microbiologia , Farmacorresistência Fúngica/genética , Genótipo , Repetições de Microssatélites , Técnicas de Tipagem Micológica , Reprodutibilidade dos Testes
6.
BMC Infect Dis ; 18(1): 491, 2018 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-30268099

RESUMO

BACKGROUND: Carbapenem resistance in Acinetobacter baumannii in China was mainly mediated by OXA-23-like carbapenemases, while OXA-24/40-like carbapenemases were rarely identified. OXA-72 is one variant of OXA-24/40-like carbapenemases. This study aimed to demonstrate the epidemiology and characterizations of OXA-72-producing A. baumannii in a Chinese hospital. METHODS: A total of 107 clinical A. calcoaceticus-A. baumannii (Acb) complex isolates were collected in a Chinese hospital during between 2014 and 2016. These isolates were identified using Vitek 2 system and gyrB multiplex PCR. Vitek 2 system was used for antibiotic susceptibility testing. Genes encoding for major classes of carbapenemases were investigated by PCR. Rep-PCR was used for genotyping of all the A. baumannii isolates. The risk factors for carriage of OXA-72-producing or OXA-23-producing A. baumannii were analyzed through univariate and multivariate logistic regression. RESULTS: Of the 107 Acb isolates collected, 101 isolates (94.4%) and 6 isolates (5.6%) were identified as A. baumannii and A. pittii, respectively. 78 A. baumannii isolates (77.2%) were carbapenem resistant and mainly cultured from intensive care unit (ICU). blaOXA-72 and blaOXA-23 genes were identified in 45(57.7%) and 33(42.3%) carbapenem-resistant A. baumannii (CRAB), respectively. Multivariate risk factor analyses showed that prior carbapenem usage and nasogastric intubation were significantly associated with carriage of OXA-72-producing A. baumannii or OXA-23-producing A. baumannii. Rep-PCR analysis showed that 9 and 22 Rep-PCR types were assigned to 78 CRAB isolates and 23 carbapenem-susceptible A. baumannii (CSAB) isolates, respectively. A higher diverstiy of Rep-PCR patterns was observed among OXA-72-producing A. baumannii isolates than OXA-23-producing A. baumannii isolates, but all of them belonged to the same clone complex. MLST analysis suggested that the OXA-72 isolates from this study correspond to CC92/CC2 clone complex. CONCLUSIONS: This study demonstrates high prevalence and potential clonal spread of closely related genotypes of OXA-72-producing A. baumannii within a Chinese hospital. Continuous surveillance is necessary to monitor the dissemination of these strains in other healthcare settings to guide infection control policies in order to curb the spread of this bacterium.


Assuntos
Infecções por Acinetobacter/diagnóstico , Acinetobacter baumannii/metabolismo , Proteínas de Bactérias/genética , beta-Lactamases/genética , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , China/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana/genética , Feminino , Humanos , Unidades de Terapia Intensiva , Modelos Logísticos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Adulto Jovem , beta-Lactamases/metabolismo
7.
Biosci Rep ; 37(2)2017 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-28115594

RESUMO

Adhesion of the knee is a major concern after knee surgery, the treatment of which is difficult. Botulinum toxin A (BTX-A) injection is demonstrated as efficient in treating knee adhesion after surgery. However, the treatment outcomes and the mechanism of action are not yet determined. The aim of the present study was to examine the effects and molecular mechanism of a BTX-A treatment in preventing adhesion of the knee. Twenty-four Wistar rats were randomly divided into a BTX-A treatment group and a control group. BTX-A or saline was injected into the cavity of the knee in the BTX-A treatment or control group respectively. Gross and histopathological examinations of interleukin 1 (IL-1) and fibroblast growth factor (FGF) levels, as well as fibroblast cell numbers, were assessed in the knee intra-articular adhesions in each group 6 weeks after recovery from the surgery. Macroscopic observations showed a significant reduction in adhesion severity in the BTX-A treatment group compared with the control group. In addition, the levels of IL-1 and FGF were lower and the number of fibroblasts was smaller in the BTX-A treatment group compared with those in the control group. BTX-A prevented intra-articular adhesion of knee in the rats, which might be associated with reduced expressions of IL-1 and FGF.


Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Membro Posterior/efeitos dos fármacos , Membro Posterior/cirurgia , Traumatismos do Joelho/tratamento farmacológico , Traumatismos do Joelho/cirurgia , Animais , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Cartilagem Articular/cirurgia , Fatores de Crescimento de Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Membro Posterior/metabolismo , Interleucina-1/metabolismo , Traumatismos do Joelho/metabolismo , Masculino , Ratos , Ratos Wistar
8.
Zhongguo Gu Shang ; 30(6): 499-502, 2017 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-29424167

RESUMO

OBJECTIVE: To investigate surgical skills and clinical effects of manipulative reduction and percutaneous Kirschner wire internal fixation in treating grade IV supination-external rotation ankle fractures. METHODS: From May 2013 to October 2016, 35 patients with grade IV supination-external rotation ankle fractures were treated with percutaneous Kirschner wire internal fixation, involving 22 males and 13 females with an average age of 38.2 years ranged from 18 to 65 years old. The time from injury to operation ranged from 2 h to 10 d with an average of 5 d. Reduction quality was assessed by Burwell-Charnley radiological criteria. Baird-Jackson ankle scoring system was used to assess clinical effects. RESULTS: Thirty-three patients were followed up from 10 to 28 months with an average of 14 months. Fracture healing time ranged from 10 to 18 weeks with an average of 12 weeks. According to Burwell-Charnley radiological criteria, 30 cases were obtained anatomic reduction, 3 cases moderate. According to Baird-Jackson ankle scoring system, total score was 93.8±5.4, 17 cases got excellent result, 12 good, 2 fair and 2 poor. CONCLUSIONS: Manipulative reduction and percutaneous Kirschner wire internal fixation in treating grade IV supination-external rotation ankle fractures has advantages of reliable efficacy, less complications. But higher require techniques were required for closed reduction. It is not suitable for severe crushed fracture and compressive articular surface fracture.


Assuntos
Fraturas do Tornozelo/cirurgia , Fios Ortopédicos , Fraturas Ósseas/cirurgia , Adulto , Idoso , Fraturas do Tornozelo/patologia , Traumatismos do Tornozelo/cirurgia , Feminino , Fixação de Fratura/métodos , Fixação Interna de Fraturas , Fraturas Ósseas/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Manipulações Musculoesqueléticas/métodos , Rotação , Supinação , Resultado do Tratamento
10.
Zhongguo Gu Shang ; 23(2): 107-10, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20345032

RESUMO

OBJECTIVE: To compare the therapeutic effect of impacted high tibial osteotomy and conventional high tibial osteotomy for the treatment of flexional medial osteoarthritis of knee joint in aged patients. METHODS: From July 2003 to July 2006, 30 patients with flexional medial knee osteoarthritis were treated with impacted high tibial osteotomy or conventional high tibial osteotomy randomly. All patients,aged from 60 to 82 years,were suffered from 7 degrees to 19 degrees knee flexion deformities and 3 to 20 years medical histories. The bone healing periods, the recover of flexion and inversion deformities, and the recover of the knee joint function were observed postoperatively. The patients were followed up at 4, 6, 8, 9, 10, 12 and 16 weeks, and 5, 7, 9 and 12 months postoperatively. The bone healing periods and the recover of flexional and inversion deformities were evaluated and compared. Twelve months postoperatively,the knee joint function were assessed with the Lysholm scoring criteria, and the therapeutic effects were compared between the two groups. RESULTS: There was a significant difference in the average bone healing period between the impacted high tibial osteotomy group (9.26 +/- 2.23) weeks and the conventional high tibial osteotomy group (11.53 +/- 3.15) weeks. The knee joint function were evaluated according to the Lysholm clinical rating scales. One year postoperatively,the average Lysholm score were (88.5 +/- 4.4) points in the impacted high tibial osteotomy group,and the results showed excellent in 14 cases, good in 1. The average Lysholm score were (78.1 +/- 5.7) points in the conventional high tibial osteotomy group. The results showed 8 cases excellent, 5 good, 2 fair, accordingly. Postoperatively, the flexion deformities of the knee in the impacted high tibial osteotomy group were -1.1 degrees to 0 degrees and was corrected averagely (130 +/- 3.30) after surgery, and that in conventional high tibial osteotomy group (140 +/- 3.30) (the same as preoperation). The average postoperative femorotibial angle (FTA) were 170.2 degrees (ranged from 169.1 degrees to 172.3 degrees) and was corrected 12.3 degrees to 12.5 degrees after surgery in both groups. CONCLUSION: Compared with conventional high tibial osteotomy, impacted high tibial osteotomy can significantly shorten the bone healing period, improve the knee flexion, varus deformity, and the knee function.


Assuntos
Osteoartrite do Joelho/cirurgia , Tíbia/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Consolidação da Fratura , Humanos , Masculino , Pessoa de Meia-Idade
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