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1.
Materials (Basel) ; 16(20)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37895686

RESUMO

Feldspar is a high-abundance mineral in the earth's crust, and its natural weathering and dissolution processes are an important phenomenon on the earth's surface. This study focused on the dissolution behavior of silicon (Si) and aluminum (Al) in feldspar minerals (microcline and albite) when exposed to low-molecular-weight organic acids (LMWOAs). Various analytical techniques, including atomic absorption spectrophotometer, X-ray diffraction, scanning electron microscope, and Fourier-transform infrared spectroscopy, were employed to investigate these processes. The results revealed that the concentration of Si and Al released from alkali feldspar increased after treatment with LMWOAs, exhibiting non-stoichiometric dissolution. The Si/Al release ratio from feldspar deviated from the expected value of three. Among the LMWOAs tested, oxalic acid was found to be more effective in dissolving aluminum, while citric acid showed greater efficacy in dissolving silicon. Notably, the composite acid demonstrated the highest capacity for feldspar dissolution, with values of 538 µM (Si) and 287 µM (Al) after treatment for 720 h, respectively. The dissolution data for Si and Al in the organic acid solution was fittingly described by a first-order equation, with high correlation coefficients (R2 ≥ 0.992). The characterization of feldspar powders indicated that the (040) crystal plane of feldspar was particularly susceptible to attack by organic acids. In the presence of these acids, the chemical bonds Si (Al)-O, Si-Si(Al), and O-Si(Al)-O shifted to higher wavenumbers. Additionally, the surface corrosion morphology of feldspar exhibited distinct nanostructures, which became more pronounced with increasing exposure time. It was also observed that the reactivity of feldspar increased over time. These findings provide valuable insights into the natural dissolution process of feldspar and offer a new perspective for the study of this phenomenon.

2.
Materials (Basel) ; 16(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36837244

RESUMO

A high sintering temperature is required to acquire excellent performance in the production of porcelain but results in high fuel consumption. To prepare the porcelain with outstanding performance at a lower temperature, a self-produced additive containing calcium (CaK) was added into a three-component system of kaolinite-feldspar-quartz. XRD and SEM were used to characterize the samples. The toughening mechanism and Gibbs free energy were investigated. After introducing the CaK, the bending strength of the porcelain fired at 1513 K increased from 56.32 ± 0.65 MPa to 95.31 ± 0.63 MPa, which was 21.83% higher than that of the porcelain without CaK at an optimal firing temperature of 1603 K. The main crystal phase of the sample comprised mullite and quartz in the raw materials at 1453~1603 K. The anorthite was observed at 1453 K and interlocked with needle-shaped mullite at 1513 K in the porcelain after adding CaK, which resulted in the higher bending strength. Quantitative analysis indicated that the amount of anorthite decreased at 1513 K and disappeared at 1543 K; the amount of mullite increased with temperature. The Gibbs free energy of the reaction (CaO•Al2O3•2SiO2 + 2(Al2O3•2SiO2) → 3Al2O3•2SiO2 + CaO + 4SiO2) at high temperature was negative, which suggested that the formation of mullite (3Al2O3•2SiO2) from anorthite (CaO•Al2O3•2SiO2) was possible. These findings implied that the addition of CaK contributed to the appropriate phase composition and microstructure, and the excellent performance of the porcelain at a lower temperature. In addition, the transformation between anorthite and mullite was possible in the special raw material system. The results are of interest in producing anorthite/mullite ceramics at reduced sintering temperatures and the conversion between anorthite and mullite.

3.
Transl Lung Cancer Res ; 10(4): 1711-1719, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34012787

RESUMO

BACKGROUND: Some pulmonary nodules are not suitable for computed tomography-guided percutaneous localization. This study aimed to investigate the feasibility and safety of real-time localization for these non-palpable pulmonary nodules using watershed analysis of the target pulmonary artery during thoracoscopic wedge resection. METHODS: Watershed analysis is a novel technique that can be used to create a specific area on the lung surface for nodule localization. This analysis is performed by temporarily blocking the target pulmonary artery and using indocyanine green fluorescence during surgery. In our study, the surgery was simulated and evaluated preoperatively using a high-precision three-dimensional reconstruction model obtained by multidetector spiral computed tomography. The lung was observed using an infrared thoracoscopy system after an intravenous injection of indocyanine green (2.5 mg/mL), and the white-to-blue transitional zone was marked using electrocautery, after which a wedge resection was performed. RESULTS: A total of 25 out of 26 patients underwent successful wedge resection. The mean tumor size and depth based on computed tomography scans were 13.2±6.4 and 12.2±7.8 mm, respectively. The mean operation duration was 142.6±52.8 min. The mean bleeding volume during surgery was 12.9±9.7 mL. The mean drainage tube indwelling time was 35.6±20.0 h, and the median length of postoperative stay was 3 days (range, 2-6 days). CONCLUSIONS: Our experience showed that the watershed analysis of the target pulmonary artery for nodule localization was safe and feasible. It may become an effective and attractive alternative method for localizing non-palpable pulmonary nodules in selected patients undergoing thoracoscopic wedge resection.

4.
Environ Sci Technol ; 55(8): 4658-4668, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33754703

RESUMO

Microplastics (MPs) pollution has caused a threat to soil ecosystem diversity and functioning globally. Recently, an increasing number of studies have reported effects of MPs on soil ecosystems. However, these studies mainly focused on soil bacterial communities and a few limited functional genes, which is why MPs effects on soil ecosystems are still not fully understood. Fertilization treatment often coinsides with MPs exposure in practice. Here, we studied effects of an environmentally relevant concentration of polyethylene on soil properties, microbial communities, and functions under different soil types and fertilization history. Our results showed that 0.2% PE MPs exposure could affect soil pH, but this effect varied according to soil type and fertilization history. Long-term fertilization history could alter effects of MPs on soil bacterial and fungal communities in diverse farmland ecosystems (P < 0.05). Soil fungal communities are more sensitive to MPs than bacterial communities under 0.2% PE MPs exposure. MPs exposure has a greater impact on the soil ecosystem with a lower microbial diversity and functional genes abundance and increases the abundance of pathogenic microorganisms. These findings provided an integrated picture to aid our understanding of the impact of MPs on diverse farmland ecosystems with different fertilization histories.


Assuntos
Microbiota , Poluentes do Solo , Ecossistema , Fazendas , Fertilização , Microplásticos , Plásticos , Solo , Microbiologia do Solo , Poluentes do Solo/análise
5.
Thorac Cancer ; 12(6): 970-973, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33502105

RESUMO

A 48-year-old woman presented to our department and chest computed tomography (CT) revealed five pulmonary nodules, two of which were in the left upper lobe of the lung and three in the superior segment of the left lower lobe., All the lesions were resected for comprehensive histological assessment in order to distinguish synchronous multiple primary lung cancers (SMPLCs) from intrapulmonary metastases. The nodules were all successfully removed by minimally invasive surgery under the guidance of three dimensional (3D) reconstruction, in order to preserve as much lung function for the patient as possible. Postoperative histopathological examination demonstrated the presence of SMPLC. The patient was discharged from hospital on postoperative day 4 without any complications.


Assuntos
Imageamento Tridimensional/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade
6.
Anal Chem ; 92(23): 15472-15479, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33169970

RESUMO

The rapid spread of antibiotic resistance threatens our fight against bacterial infections. Environments are an abundant reservoir of potentially transferable resistance to pathogens. However, the trajectory of antibiotic resistance genes (ARGs) spreading from environment to clinic and the associated risk remain poorly understood. Here, single-cell Raman spectroscopy combined with reverse D2O labeling (Raman-rD2O) was developed as a sensitive and rapid phenotypic tool to track the spread of plasmid-borne ARGs from soil to clinical bacteria via transformation. Based on the activity of bacteria in assimilating H to substitute prelabeled D under antibiotic treatment, Raman-rD2O sensitively discerned a small minority of phenotypically resistant transformants from a large pool of recipient cells. Its single-cell level detection greatly facilitated the direct calculation of spread efficiency. Raman-rD2O was further employed to study the transfer of complex soil resistant plasmids to pathogenic bacteria. Soil plasmid ARG-dependent transformability against five clinically relevant antibiotics was revealed and used to assess the spreading risk of different soil ARGs, i.e., ampicillin > cefradine and ciprofloxacin > meropenem and vancomycin. The developed single-cell phenotypic method can track the fate and risk of environmental ARGs to pathogenic bacteria and may guide developing new strategies to prevent the spread of high-risk ARGs.


Assuntos
Resistência Microbiana a Medicamentos/genética , Fenótipo , Análise de Célula Única/métodos , Análise Espectral Raman/métodos , Humanos , Plasmídeos/genética , Risco , Coloração e Rotulagem
7.
Ann Thorac Surg ; 109(4): 1040-1046, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31926158

RESUMO

BACKGROUND: Patients undergoing thoracic lung wedge resection could benefit from tubeless strategies. However, postoperative pneumothorax is a primary limiting factor for such strategies. Accordingly, we evaluated the safety and efficacy of the prophylactic use of an air-extraction catheter as an improved drainage strategy and compared the findings with those for chest tube drainage in patients undergoing thoracic wedge resection. METHODS: Patients undergoing thoracic wedge resection between August 2017 and October 2018 were enrolled in this single-center, randomized, open-label, noninferiority trial. Patients who received an improved drainage strategy involving the use of a prophylactic air-extraction catheter were randomized to the intervention group, whereas those who underwent routine chest tube drainage were assigned to the control group. Analysis was based on the per-protocol population. The primary outcome was the incidence of pneumothorax on postoperative day 1. Secondary outcomes included patient recovery and related complications, including pleural effusion, lung infection, numeric rating scale score for pain, postoperative chest tube or catheter removal, postoperative hospitalization, and chest tube reinsertion. RESULTS: A total of 96 patients were randomized. Baseline demographic and clinical characteristics were similar between groups. The incidence of pneumothorax in the intervention and control groups was 10.0% and 9.1%, respectively (noninferiority, P = 1.00). In addition, there were no significant between-group differences in secondary outcomes. A significantly lower pain score was observed in the intervention group (P = .001). CONCLUSIONS: The improved drainage strategy is not inferior to standard chest tube drainage after thoracic wedge resection and should be popularized.


Assuntos
Drenagem/métodos , Pneumopatias/cirurgia , Pneumonectomia/efeitos adversos , Pneumotórax/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Toracoscopia/efeitos adversos , Adulto , Idoso , Tubos Torácicos , Feminino , Humanos , Incidência , Pneumopatias/complicações , Masculino , Pessoa de Meia-Idade , Pneumotórax/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos
8.
Sci Rep ; 8(1): 15861, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367176

RESUMO

In this prospective study, we compared the performance of readout segmentation of long variable echo trains of diffusion-weighted imaging (RESOLVE DWI) and diffusion kurtosis imaging (DKI) for the prediction of radiotherapy response in patients with nasopharyngeal carcinoma (NPC). Forty-one patients with NPC were evaluated. All patients underwent conventional MRI, RESOLVE DWI and DKI, before and after radiotherapy. All patients underwent conventional MRI every 3 months until 1 year after radiotherapy. The patients were divided into response group (RG; 36/41 patients) and no-response group (NRG; 5/41 patients) based on follow-up results. DKI (the mean of kurtosis coefficient, Kmean and the mean of diffusion coefficient, Dmean) and RESOLVE DWI (the minimum apparent diffusion coefficient, ADCmin) parameters were calculated. Parameter values at the pre-treatment period, post-treatment period, and the percentage change between these 2 periods were obtained. All parameters differed between the RG and NRG groups except for the pretreatment Dmean and ADCmin. Kmean-post was considered as an independent predictor of local control, with 87.5% sensitivity and 91.3% specificity (optimal threshold = 0.30, AUC: 0.924; 95% CI, 0.83-1.00). Kmean-post values of DKI have the potential to be used as imaging biomarkers for the early evaluation of treatment effects of radiotherapy on NPC.


Assuntos
Biomarcadores/análise , Imagem de Tensor de Difusão/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Adulto , Idoso , Área Sob a Curva , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Curva ROC , Resultado do Tratamento , Adulto Jovem
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