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1.
BMC Public Health ; 24(1): 67, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166770

RESUMO

BACKGROUND: Hepatitis B mother-to-child transmission interruption (PMTCT) poses a formidable challenge in underdeveloped regions of China. This study aims to evaluate the effectiveness of PMTCT and the health management team (HMT) model in Ningxia, China, as well as the risk factors for adverse outcomes. METHODS: The PMTCT + HMT model was established, and 360 pregnant women diagnosed with HBV infection in 2020-2022 were selected and divided into the control and the study groups based on different intervention modes. HBV serum markers and HBV DNA levels were assessed, the indicators of compliance behaviors and adverse outcomes were compared, and the factors influencing adverse outcomes were analyzed. RESULTS: The majority of subjects were residents of the local city, married, with secondary school or higher education, and employees of public sectors. The proportion of ethnic minorities was 40.8% and 34.2% in the control group and study group. HBeAg positivity was 23.3% and 26.3%, and the proportion with HBV DNA levels ≥ 2 × 105 IU/mL was 9.2% and 7.1%. Compared with the control group (PMTCT alone), the PMTCT + HMT model led to improved maternal knowledge (17.5% vs. 57.1%), voluntary counseling (34.2% vs. 63.3%), and testing (37.5% vs. 70.4%). The incidence of adverse pregnancy outcomes ((including miscarriage, preterm birth) decreased significantly (17.5% vs. 6.2%), as did adverse neonatal outcomes (low birth weight and congenital HBV) (26.9% vs. 10.5%). Adverse outcomes were associated with low educational attainment, non-locals, unmarried status, and ethnic minority identity. Additionally, HBeAg positivity and HBV DNA levels ≥ 2 × 105 IU/mL were risk factors for adverse outcomes. CONCLUSIONS: The PMTCT + HMT model demonstrates significant effectiveness in preventing mother-to-child transmission of hepatitis B in Ningxia. The unique demographic structure of Ningxia region is closely linked to poor outcomes, emphasizing the importance of monitoring HBeAg status and HBV DNA viral load level.


Assuntos
Hepatite B , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Feminino , Recém-Nascido , Gravidez , Humanos , Vírus da Hepatite B , Antígenos E da Hepatite B , Antígenos de Superfície da Hepatite B , DNA Viral , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Etnicidade , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Grupos Minoritários , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , China/epidemiologia
2.
Plant Biotechnol J ; 17(11): 2199-2210, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31004551

RESUMO

Hongkong kumquat (Fortunella hindsii) is a wild citrus species characterized by dwarf plant height and early flowering. Here, we identified the monoembryonic F. hindsii (designated as 'Mini-Citrus') for the first time and constructed its selfing lines. This germplasm constitutes an ideal model for the genetic and functional genomics studies of citrus, which have been severely hindered by the long juvenility and inherent apomixes of citrus. F. hindsii showed a very short juvenile period (~8 months) and stable monoembryonic phenotype under cultivation. We report the first de novo assembled 373.6 Mb genome sequences (Contig-N50 2.2 Mb and Scaffold-N50 5.2 Mb) for F. hindsii. In total, 32 257 protein-coding genes were annotated, 96.9% of which had homologues in other eight Citrinae species. The phylogenomic analysis revealed a close relationship of F. hindsii with cultivated citrus varieties, especially with mandarin. Furthermore, the CRISPR/Cas9 system was demonstrated to be an efficient strategy to generate target mutagenesis on F. hindsii. The modifications of target genes in the CRISPR-modified F. hindsii were predominantly 1-bp insertions or small deletions. This genetic transformation system based on F. hindsii could shorten the whole process from explant to T1 mutant to about 15 months. Overall, due to its short juvenility, monoembryony, close genetic background to cultivated citrus and applicability of CRISPR, F. hindsii shows unprecedented potentials to be used as a model species for citrus research.


Assuntos
Sistemas CRISPR-Cas , Citrus/genética , Edição de Genes , Genoma de Planta , Plantas Geneticamente Modificadas
3.
J Environ Qual ; 43(5): 1656-62, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25603251

RESUMO

Soil fumigation is an important treatment in the production chain of fruit and vegetable crops, but fumigant emissions contribute to air pollution. Biochar as a soil amendment has shown the potential to reduce organic pollutants, including pesticides, in soils through adsorption and other physicochemical reactions. A laboratory column study was performed to determine the effects of soil applications of biochar for reducing emissions of the fumigant 1,3-dichloropropene (1,3-D). The experimental treatments comprised of unamended and amended with biochar at doses of 0, 0.5, 1, 2, and 5% (w/w) in the top 5 cm soil layer. The unamended treatment resulted in the highest emission peak flux at 48 to 66 µg m s. Among the biochar amendment treatments, the highest peak flux (0.83 µg m s) was found in the biochar 0.5% treatment. The total emission loss was 35.7 to 40.2% of applied for the unamended treatment and <0.1 to 2.9% for the biochar-amendment treatments. A germination bioassay with cucumber seeds showed that ≥7 d of aeration would be needed to avoid phytotoxicity before replanting in biochar-containing fumigated soil. The results indicate that treatments with 0.5% or more biochar amendment reduced emission peak flux by >99.8% and showed total 1,3-D emission loss by >92% compared with that without biochar. The amendment of surface soil with biochar shows a great potential for reducing fumigant emissions.

4.
Breast ; 76: 103762, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38924994

RESUMO

BACKGROUND: Male breast cancer (MBC) is a rare disease. Although several large-scale studies have investigated MBC patients in other countries, the features of MBC patients in China have not been fully explored. This study aims to explore the features of Chinese MBC patients comprehensively. METHODS: We retrospectively collected data of MBC patients from 36 centers in China. Overall survival (OS) was evaluated by the Kaplan-Meier method, log-rank test, and Cox regression analyses. Multivariate Cox analyses were used to identify independent prognostic factors of the patients. RESULTS: In total, 1119 patients were included. The mean age at diagnosis was 60.9 years, and a significant extension over time was observed (P < 0.001). The majority of the patients (89.1 %) received mastectomy. Sentinel lymph node biopsy was performed in 7.8 % of the patients diagnosed in 2009 or earlier, and this percentage increased significantly to 38.8 % in 2020 or later (P < 0.001). The five-year OS rate for the population was 85.5 % [95 % confidence interval (CI), 82.8 %-88.4 %]. Multivariate Cox analysis identified taxane-based [T-based, hazard ratio (HR) = 0.32, 95 % CI, 0.13 to 0.78, P = 0.012] and anthracycline plus taxane-based (A + T-based, HR = 0.47, 95 % CI, 0.23 to 0.96, P = 0.037) regimens as independent protective factors for OS. However, the anthracycline-based regimen showed no significance in outcome (P = 0.175). CONCLUSION: As the most extensive MBC study in China, we described the characteristics, treatment and prognosis of Chinese MBC population comprehensively. T-based and A + T-based regimens were protective factors for OS in these patients. More research is required for this population.


Assuntos
Neoplasias da Mama Masculina , Mastectomia , Biópsia de Linfonodo Sentinela , Humanos , Neoplasias da Mama Masculina/patologia , Neoplasias da Mama Masculina/mortalidade , Neoplasias da Mama Masculina/terapia , Neoplasias da Mama Masculina/epidemiologia , Masculino , Pessoa de Meia-Idade , China/epidemiologia , Estudos Retrospectivos , Mastectomia/estatística & dados numéricos , Idoso , Biópsia de Linfonodo Sentinela/estatística & dados numéricos , Adulto , Prognóstico , Modelos de Riscos Proporcionais , Estimativa de Kaplan-Meier , Taxoides/uso terapêutico , Taxa de Sobrevida , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Antraciclinas/uso terapêutico , Idoso de 80 Anos ou mais
5.
Cell Transplant ; 32: 9636897231202541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37798942

RESUMO

This study aims to investigate the effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2VitD3) on osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) and the activity of hPDLSC sheets and the differences in the tissue regeneration activity of hPDLSC sheets on tooth root fragment treated by different methods. Healthy caries-free premolars were collected. The hPDLSCs were obtained by enzymatic digestion. Surface markers of stem cells were analyzed by flow cytometry and the multidirectional differentiation ability of hPDLSCs was detected. During the osteogenic differentiation of hPDLSCs, 1,25(OH)2VitD3 was added and the effect of 1,25(OH)2VitD3 on osteogenic differentiation of hPDLSCs was assessed using Western blotting, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay, cell staining, and immunofluorescence. After hPDLSC sheets were prepared, histology and immunofluorescence analysis of the effect of 1,25(OH)2VitD3 on sheet activity were performed. In addition, root fragments were prepared and treated with scaling, 24% EDTA (ethylenediamide tetraacetic acid), and Er,Cr:YSGG lasers, respectively, and the tissue regeneration activity of hPDLSC sheets on different root fragments were observed. 1,25(OH)2VitD3 promoted the high gene and protein expressions of osteogenic markers ALP (alkaline phosphatase), Runx2, and OPN (osteopontin antibody) in hPDLSCs, along with enhanced ALP activity and staining, alizarin red staining, and immunofluorescence staining, indicating that the osteogenic differentiation ability of hPDLSCs was improved. Extracellular matrix secretion was increased in hPDLSC sheets, along with the positive expressions of the protein markers fibronectin and collagen I, suggesting that 1,25(OH)2VitD3 could enhance these effects. In addition, the root fragments treated by Er,Cr:YSGG laser were more suitable for the attachment and regeneration of hPDLSC sheets, demonstrating that 1,25(OH)2VitD3 could improve the tissue regeneration performance of these sheets. 1,25(OH)2VitD3 can promote osteogenic differentiation of hPDLSCs and thus plays an active role in hPDLSC sheet formation and tissue regeneration. In addition, the Er,Cr:YSGG laser can be used as the recommended treatment method for the root surface regenerated by hPDLSCs.


Assuntos
Osteogênese , Ligamento Periodontal , Humanos , Osteogênese/genética , Calcitriol/farmacologia , Calcitriol/metabolismo , Células-Tronco , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas
6.
J Steroid Biochem Mol Biol ; 232: 106347, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37331433

RESUMO

Periodontitis is a chronic inflammatory disease caused by Porphyromonas gingivalis and other bacteria, and human periodontal ligament stem cells (hPDLSCs) are a promising candidate for the treatment of periodontal supporting tissue defects. This study aimed to investigate the effect of 1α,25-dihydroxyvitamin D3 [1,25(OH)2VitD3] on osteogenic differentiation of hPDLSCs in an in vitro periodontitis model and whether it can improve inflammatory status. hPDLSCs were in vitro isolated and identified. After treatment with 1,25(OH)2VitD3 and ultrapure pure Porphyromonas gingivalis lipopolysaccharide (LPS-G), the viability of hPDLSCs was detected using Cell Counting Kit-8, the expressions of osteogenic markers and inflammatory genes using Western blotting and quantitative reverse transcription PCR (qRT-PCR), the levels of inflammatory factors in cells using enzyme linked immunosorbent assay (ELISA), and the fluorescence signal intensity of osteoblastic markers and inflammatory genes in cells using immunofluorescence assay. It was found that 1,25(OH)2VitD3 reversed the inhibition of hPDLSCs proliferation by LPS-G; LPS-G exhibited inhibitory effect on ALP, Runx2, and OPN expressions, and such inhibitory effect was significantly weakened when co-acting with 1,25(OH)2VitD3. Meanwhile, LPS-G upregulated the expressions of inflammatory genes IL-1ß and Casp1, whereas 1,25(OH)2VitD3 antagonized such an effect and improved the inflammatory status. In conclusion, 1,25(OH)2VitD3 can reverse the inhibitory effect of LPS-G on hPDLSCs proliferation and osteogenic differentiation and suppress LPS-G-induced upregulation of inflammatory gene expressions.


Assuntos
Osteogênese , Periodontite , Humanos , Ligamento Periodontal , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Periodontite/metabolismo , Inflamação/metabolismo , Células-Tronco , Diferenciação Celular , Células Cultivadas
7.
Front Neurol ; 14: 1105616, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846119

RESUMO

Objective: This study aims to establish a radiomics-based machine learning model that predicts the risk of transient ischemic attack in patients with mild carotid stenosis (30-50% North American Symptomatic Carotid Endarterectomy Trial) using extracted computed tomography radiomics features and clinical information. Methods: A total of 179 patients underwent carotid computed tomography angiography (CTA), and 219 carotid arteries with a plaque at the carotid bifurcation or proximal to the internal carotid artery were selected. The patients were divided into two groups; patients with symptoms of transient ischemic attack after CTA and patients without symptoms of transient ischemic attack after CTA. Then we performed random sampling methods stratified by the predictive outcome to obtain the training set (N = 165) and testing set (N = 66). 3D Slicer was employed to select the site of plaque on the computed tomography image as the volume of interest. An open-source package PyRadiomics in Python was used to extract radiomics features from the volume of interests. The random forest and logistic regression models were used to screen feature variables, and five classification algorithms were used, including random forest, eXtreme Gradient Boosting, logistic regression, support vector machine, and k-nearest neighbors. Data on radiomic feature information, clinical information, and the combination of these pieces of information were used to generate the model that predicts the risk of transient ischemic attack in patients with mild carotid artery stenosis (30-50% North American Symptomatic Carotid Endarterectomy Trial). Results: The random forest model that was built based on the radiomics and clinical feature information had the highest accuracy (area under curve = 0.879; 95% confidence interval, 0.787-0.979). The combined model outperformed the clinical model, whereas the combined model showed no significant difference from the radiomics model. Conclusion: The random forest model constructed with both radiomics and clinical information can accurately predict and improve discriminative power of computed tomography angiography in identifying ischemic symptoms in patients with carotid atherosclerosis. This model can aid in guiding the follow-up treatment of patients at high risk.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36141835

RESUMO

Based on the data from the 2012-2018 China Family Panel Survey, this study examines the impact of household wealth on individuals' mental health using a two-way fixed effects model. The findings indicate that household wealth exerts a significant positive effect on individuals' mental health. Furthermore, this study shows that the impact of household wealth on individuals' mental health is nonlinear but inverted U-shaped. Considering the possible endogeneity problem, this study further examines the effect of household wealth on residents' mental health using two-stage least squares, and the conclusions remain robust. The results of the heterogeneity analysis indicate that household wealth has a greater impact on the mental health of residents in the low-education group and western region. Furthermore, the results of the mechanisms reveal that household wealth affects mental health by influencing insurance investment and individuals' labor supply. Moreover, this study finds that household wealth affects individuals' mental health not only in the short term but also in the medium and long terms. This study provides policy implications for the government toward improving individuals' mental health.


Assuntos
Saúde Mental , China/epidemiologia , Humanos , Fatores Socioeconômicos , Inquéritos e Questionários , Recursos Humanos
9.
Zhonghua Wai Ke Za Zhi ; 49(10): 907-10; discussion 911-3, 2011 Oct 01.
Artigo em Zh | MEDLINE | ID: mdl-22321681

RESUMO

OBJECTIVE: To study the assessment and management for abdominal aortic aneurysm (AAA)'s special distal landing zones in endovascular repair (EVAR). METHODS: The clinic data of 66 AAA patients with complicated distal landing zones From January 2007 to December 2010 was retrospectively analyzed. There were 45 male and 21 female patients, aged from 53 to 87 years with a mean of 62 years. All patients underwent the CT angiography examination (1 to 2 mm interval) to obtain the necessary anatomical data. In this group, there were 20 cases with type I and IIA lesions, including 10 cases with narrow common iliac arteries/external iliac arteries (> 50%), 6 cases with seriously distorted common iliac arteries/external iliac arteries, 4 cases with the characters of the above, 16 cases with bilateral common iliac aneurysms, 46 cases with bilateral common iliac aneurysms combined internal iliac aneurysms (unilateral 32 cases, bilateral 14 cases). The vascular stent-grafts' usage was as follow: Metronic 46 cases, COOK 14 cases, Microport 4 cases, Lifetech 2 cases. RESULTS: The mean operative time was 90 min. There were significant stent-graft shortening in 22 cases (33.3%), type II endoleak in 18 cases (27.3%), type III endoleak in 5 cases (7.6%), iliac stents' stenosis (> 50%) in 2 cases (3.0%), type II combined with type III endoleak in 5 cases (7.6%), iliac stents' stenosis combined with type III endoleak in 4 cases (6.1%). Patients were followed for a mean of 22 months (range from 3 to 36 months), during the time of follow-up, the following conditions were observed: stent-graft displacement (to the remote < 10 mm) in 2 cases (3.0%), iliac stents restenosis (> 50%) 2 cases, type II endoleak healed in 18 cases (18/23, 78.3%), and no type III endoleak remained. The fatality rate was 3.0% (2/66). CONCLUSIONS: Special distal landing zones increased the operative complication rate in EVAR. Being familiar with the features of stent-graft and appropriate use of various surgical management can increase the success ratio of EVAR.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Stents , Resultado do Tratamento
10.
World J Clin Cases ; 9(23): 6624-6638, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34447810

RESUMO

Nonalcoholic fatty pancreas disease (NAFPD) is an emerging disease that has gained an increasing amount of attention in recent years. It describes fat accumulation in the pancreas with insignificant alcohol consumption, but the pathogenesis is largely unknown. A wide range of terms have been used to describe the phenomenon of pancreatic fat accumulation, but NAFPD remains an under-recognized and non-independent disorder. Obesity, age, sex, race, and unhealthy lifestyle are established independent risk factors for NAFPD, which is strongly associated with metabolic syndrome, type 2 diabetes, pancreatitis, pancreatic fistula, pancreatic cancer, and nonalcoholic fatty liver disease. At present, imaging techniques are common diagnostic aids, but uniform criteria and consensus are lacking. Therapeutically, healthy diet, weight loss, and exercise are the mainstays to reduce pancreatic fat accumulation. It can be seen that there is a limited understanding of NAFPD at this stage and further exploration is needed. Previous studies have revealed that NAFPD may directly affect diagnosis and clinical decision-making. Therefore, exploring the pathophysiological mechanism and clinical associations of NAFPD is a major challenge for researchers and clinicians.

11.
Micromachines (Basel) ; 12(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34357211

RESUMO

Focusing on service control factors, rapid changes in manufacturing environments, the difficulty of resource allocation evaluation, resource optimization for 3D printing services (3DPSs) in cloud manufacturing environments, and so on, an indicator evaluation framework is proposed for the cloud 3D printing (C3DP) order task execution process based on a Pareto optimal set algorithm that is optimized and evaluated for remotely distributed 3D printing equipment resources. Combined with the multi-objective method of data normalization, an optimization model for C3DP order execution based on the Pareto optimal set algorithm is constructed with these agents' dynamic autonomy and distributed processing. This model can perform functions such as automatic matching and optimization of candidate services, and it is dynamic and reliable in the C3DP order task execution process based on the Pareto optimal set algorithm. Finally, a case study is designed to test the applicability and effectiveness of the C3DP order task execution process based on the analytic hierarchy process and technique for order of preference by similarity to ideal solution (AHP-TOPSIS) optimal set algorithm and the Baldwin effect.

12.
Micromachines (Basel) ; 12(11)2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34832838

RESUMO

In order to reduce the cost of manufacturing and service for the Cloud 3D printing (C3DP) manufacturing grid, to solve the problem of resources optimization deployment for no-need preference under circumstance of cloud manufacturing, consider the interests of enterprises which need Cloud 3D printing resources and cloud platform operators, together with QoS and flexibility of both sides in the process of Cloud 3D printing resources configuration service, a task-service network node matching method based on Multi-Objective optimization model in dynamic hyper-network environment is built for resource allocation. This model represents interests of the above-mentioned two parties. In addition, the model examples are solved by modifying Mathematical algorithm of Node Matching and Evolutionary Solutions. Results prove that the model and the algorithm are feasible, effective and stable.

13.
Int Angiol ; 39(4): 314-322, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32138469

RESUMO

BACKGROUND: We present the expression of miR-146a in abdominal aortic aneurysms (AAA) patients, and its mechanism for regulating inflammation and development in AAA patients. METHODS: The expression of miR-146a in serum, PBMC, and abdominal aorta tissues was measured in AAA patients. RESULTS: We found that level of miR-146a in the serum and its expression in AAA tissues were significantly higher than that in healthy people or normal abdominal aorta tissues. Pearson's method analysis showed that miRNA-146a in the serum of AAA patients was negatively correlated with serum TNF-α, IFN-γ and CRP, and was positively correlated with serum IL-10. The luciferase reporter gene system confirmed that miR-146a targeted inhibition of CARD10 expression in THP-1 and human umbilical vein endothelial cells (HUVECs), and miR-146a was negatively correlated with the expression of CARD10 in the tissues/PBMC of AAA patients. In PBMC of healthy people, over-expression of miR-146a by transferring miR-146a-mimic could increase the expression of SIRT1 but decreased the expression of p65 and the level of TNF-α secretion. Moreover, HUVECs cellular activity change by TNF-α in a dose-dependent manner. CONCLUSIONS: These results suggested that miR-146a suppressed the inflammation of peripheral blood in AAA patients by targeting CARD10, and miR-146a blocked the progression of AAA through CARD10/SIRT1/p65 pathway.


Assuntos
Aneurisma da Aorta Abdominal , Proteínas Adaptadoras de Sinalização CARD , MicroRNAs , Aneurisma da Aorta Abdominal/genética , Células Endoteliais , Humanos , Inflamação , Leucócitos Mononucleares , MicroRNAs/genética
14.
Ann Transl Med ; 8(10): 649, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32566586

RESUMO

BACKGROUND: In Chinese culture, smoking can promote social connectedness and integration. We therefore hypothesized that smoking would be negatively associated with loneliness in China. Given that loneliness is common and associated with adverse academic and health outcomes in university freshmen, examining correlates of loneliness in this population may deepen our understanding on the etiology of loneliness. This study investigated the association between smoking and loneliness in Chinese university fresh students. METHODS: In this cross-sectional study, by using a two-stage cluster sampling approach, we recruited a total of 1,452 fresh students from a comprehensive university in Wuhan, China. These students completed a self-administered questionnaire containing the Chinese six-item De Jong Gierveld Loneliness Scale (DJGLS) and standardized questions on socio-demographics, internet use, and substance use, including smoking and use of alcohol and illicit drugs. Multiple linear regression was used to test the independent association of loneliness with smoking. RESULTS: In Chinese university freshmen, current smokers had significantly higher DJGLS scores than non-smokers (11.9±4.60 vs. 8.53±3.72, t=7.351, P<0.001). After controlling for socio-demographic variables, current drinking, lifetime illicit drug use, and daily hours of internet use, the positive association between current smoking and DJGLS score remained statistically significant (unstandardized coefficient: 3.053, P<0.001). CONCLUSIONS: Smoking is independently and positively associated with loneliness in Chinese university freshmen. Smoking cessation might be helpful for preventing and reducing loneliness among Chinese university fresh students.

15.
Waste Manag ; 101: 180-187, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622863

RESUMO

With the rapid development of photovoltaic industry, the recycling of waste solar photovoltaic (PV) panels is becoming a critical and global challenge. Considering PV panels recycling is significantly effective and worthwhile to save natural resources and reduce the cost of production, how to selectively recycle valuable components of PV panels is the hot and dominant topic. Different from current mechanical crushing, heat treatment and chemical operation processes, novel and environment-friendly recycling approaches by using high voltage pulse discharge in water, called high voltage fragmentation (HVF), was discussed under different discharge conditions. The results showed that discharging across surface and interior of PV panels produced ablation round holes, sputter metal particles and dendritic channels. The average particle size decreased with the ascent of pulse number and voltage amplitude. Considering the energy consumption, the optimal condition of HVF in this paper was 160 kV for 300 pulses with the energy consumption of 192.99 J/g, crushing the PV panels into particles of 4.1 mm in average (13.7% of the initial size). More particle was distributed among the 0.1-2 mm size fractions as the energy increased. Selective fragmented products, such as Cu, Al, Pb, Ag and Sn, are concentrated on the fractions under 1 mm. Finally, hybrid crushing energy consumption model combined with fractal theory was discussed, which presented close relationship between energy and average particle size. Walker's model (n = 2.047 determined by fractal theory) had the best fitting effect.


Assuntos
Resíduo Eletrônico , Metais , Reciclagem
16.
Chemosphere ; 212: 563-571, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30165283

RESUMO

Chloropicrin fumigation had strong inhibitory effect on soil N cycling. Knowledge gap existed about the performance of reactive N in soil applied with different amendments used to improve the fumigation function or soil quality. In this study, we employed four amendments, i.e., wheat straw residue, manure, biochar and ammonium thiosulfate, incorporated into soil at the regular application rate. Simultaneously, bare soil was selected as control (CK). Based on a three months incubation assay, soil reactive N and activity of three enzymes governing N-mineralization was measured, i.e., protease, arylamidase and l-glutaminase, as well the soil fluorescein diacetate (FDA) hydrolysis, basal soil respiration, and dissolved soil organic carbon (DOC). Result showed that, compared with the bare soil, the addition of straw or manure to soil markedly enhanced the FDA and the resistance of arylamidase and l-glutaminase to the fumigation, while significantly decreased the concentration of DON, NH4+N and NO3--N. The addition of biochar to soil had no effect on the reactive N, but contrasting effects on the three enzymes, i.e., suppressed protease activity, and enhanced arylamidase activity. The ammonium thiosulfate showed an inert effect on the measured microbiological indices and reactive N except the enhanced concentration of NH4+N. DOC content of amendments governed microbial activity under fumigation condition. In synthesis, our findings suggested that under chloropicrin fumigation the use of straw or manure enhanced the microbial abundance and the activity of N-mineralization enzymes, which may lead to low reactive N by the microbial N immobilization for a longer period.


Assuntos
Fumigação/métodos , Hidrocarbonetos Clorados/efeitos adversos , Solo/química
17.
Artigo em Zh | MEDLINE | ID: mdl-27062855

RESUMO

OBJECTIVE: To investigate the ability of autologous peripheral blood endothelial progenitor cells (EPCs) in promoting neovascularization of tissue engineered bone and osteogenesis of bone marrow mesenchymal stem cells (BMSCs). METHODS: The peripheral blood EPCs and BMSCs from No. 1-9 New Zealand rabbits were isolated, cultured, and identified. According to the cell types, the third generation of cells were divided into 3 groups: EPCs (group A), BMSCs (group B), and co-cultured cells of EPCs and BMSCs (group C, EPCs : BMSCs = 1 : 2). Then cells were seeded on the partially deproteinised bone (PDPB) packaged with fibronectin to construct tissue engineered bone. After 4 days, autologous heterotopic transplantation of tissue engineered bone was performed in the rabbit's muscles bag of groups A, B, and C (the right arm, left arm, right lower limb respectively, 2 pieces each part). At 2, 4, and 8 weeks after transplantation, the growth of tissue engineered bone was observed, and the rate of bone ingrowth was calculated by HE staining; the expressions of CD34, CD105, and zonula occludens protein 1 (ZO-1) were compared by immunohistochemical staining at each time point in tissue engineered bone among 3 groups. RESULTS: The EPCs and BMSCs were isolated and identified successfully; immunofluorescent staining showed that EPCs were positive for CD34, CD133, and von Willebrand factor (vWF), and BMSCs were positive for CD29 and CD90 and were negative for CD34. The tissue engineered bone constructed in 3 groups was transplanted successfully. At 2, 4, and 8 weeks after autologous heterotopic transplantation, the general observations showed that the soft tissue around the tissue engineered bone increased and thickened gradually in each group with time passing; the boundary between bone and soft tissue was not clear; the pore space of tissue engineered bone gradually was filled, especially in group C, the circuitous vascular network could be seen in the tissue engineered bone. HE staining showed capillaries and collagen fibers increased gradually, tissue engineered bone ingrowth rate was significantly higher in group C than groups A and B at 4 and 8 weeks (P < 0.05), and group B was significantly higher than group A (P < 0.05). Immunohistochemical staining showed that the expressions of CD34, CD105, and ZO-1 in tissue engineered bone of 3 groups all increased with the extension of time, showing significant differences between groups at each time point (P < 0.05). At 2 weeks after transplantation, the expression of CD 105 in group C was significantly higher than that in groups A and B (P < 0.05); at 4 and 8 weeks, CD34, CD 105, and ZO-1 expressions showed significant differences between 2 groups (P < 0.05); the expression was the highest in group C, and was the lowest in group B. CONCLUSION: Autologous peripheral blood EPCs and BMSCs have synergistic effect, and can promote neovascularization and osteogenesis of tissue engineered bone in vivo.


Assuntos
Neovascularização Patológica , Osteogênese , Engenharia Tecidual , Animais , Osso e Ossos , Células Cultivadas , Técnicas de Cocultura , Células Progenitoras Endoteliais , Coelhos , Transplante Autólogo
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