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1.
Environ Res ; : 110713, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33428908

RESUMO

To prevent the illegal discharge of metal plating wastewater (MPW), it is necessary to explore a monitoring method that could achieve the identification of MPW in natural water bodies. Fluorescence excitation-emission matrix-parallel factor (EEM-PARAFAC) analysis might be a promising tool for the detection of MPW. However, before conducting the practical monitoring, the apparent fluorescence features of different kinds of MPW must be first understood. In this study, six types of MPW (576 samples) from ten metal plating plants were collected and their fluorescence fingerprints (FFs) were characterized by EEM-PARAFAC analysis. Results showed that pretreatment wastewater (PTW), copper-contained electroplating wastewater (Cu-EPW), copper-contained electroless wastewater (Cu-ELW), nickel-contained electroplating wastewater (Ni-EPW), Ni-ELW, and metal plating effluent (MPE) presented one, three, one, one, two, and three types of FFs, respectively. Among them, three individual fluorescent components were identified in Ni-EPW and two were decomposed in other kinds of MPW. Owing to the discrepancies of production processes, electroplating additives, wastewater treatment techniques, and management levels, different metal plating plants owned different FFs. By spectral comparison, the tyrosine-like components in PTW and Ni-ELW might derived from some phenolic and benzenesulfonic acidic compounds. Fluorescent component similarity analysis indicated that EEM-PARAFAC technique could distinguish the raw and treated MPW. This study not only constructed the first FF database for MPW, but also provided valuable guidance for their practical monitoring in aquatic environment.

2.
Neural Regen Res ; 16(8): 1606-1612, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33433491

RESUMO

In a previous study, we used natural butterfly wings as a cell growth matrix for tissue engineering materials and found that the surface of different butterfly wings had different ultramicrostructures, which can affect the qualitative growth of cells and regulate cell growth, metabolism, and gene expression. However, the biocompatibility and biosafety of butterfly wings must be studied. In this study, we found that Sprague-Dawley rat dorsal root ganglion neurons could grow along the structural stripes of butterfly wings, and Schwann cells could normally attach to and proliferate on different species of butterfly wings. The biocompatibility and biosafety of butterfly wings were further examined through subcutaneous implantation in Sprague-Dawley rats, intraperitoneal injection in Institute of Cancer Research mice, intradermal injection in rabbits, and external application to guinea pigs. Our results showed that butterfly wings did not induce toxicity, and all examined animals exhibited normal behaviors and no symptoms, such as erythema or edema. These findings suggested that butterfly wings possess excellent biocompatibility and biosafety and can be used as a type of tissue engineering material. This study was approved by the Experimental Animal Ethics Committee of Jiangsu Province of China (approval No. 20190303-18) on March 3, 2019.

3.
Inorg Chem ; 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33442984

RESUMO

Tin oxide based materials have attracted much attention as new sources for nonlinear optical (NLO) devices, while the electronic mechanism behind the structure and nonlinearity is still unclear. In this work, by precisely controlling different functionalization ligands, here a series of binuclear [(nBuSn)2(TEOA)2L2] (L = monocarboxylic acid ligand) complexes have been synthesized and characterized; we also adopted a new method to make the metal clusters and PMMA blend together for NLO testing. Importantly, the electronic structure, static third-order NLO properties, sum over states (SOS) have been studied by both experimental and density function theory (DFT) analysis. The effects for general NLO polarizability under various conditions, including different substitutions ligands and replacement of the metal cores, have been further investigated. The results indicate the static second hyperpolarizabilities (γ) is inversely proportional to the band gap decreases. Notably, the theory predicts that the third-order nonlinear coefficient will double through the synergistic effects of pull-push groups. The hole-electron analysis of the main excited states indicates the simultaneous introduction of pull-push electron groups into the system cause the excitation of the valence layer from LE to LLCT, which also leads to significant increase in the γ value of complex 13. This work demonstrates that an efficient adjustment for the intensity of NLO polarizability can be achieved by regulating the substitutions and the material structures, providing a new potential for the application of tin-oxo clusters in the field of nonlinear optics.

4.
Medicine (Baltimore) ; 100(1): e24120, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33429783

RESUMO

BACKGROUND: Evaluating the effectiveness and safety of external treatment of traditional Chinese medicine therapy for COVID-19 with diarrhea is the primary purpose of this systematic evaluation program. METHODS: We will search the randomized controlled trials from inception to November 2020. The following database is our focus area: Cochrane Central Register of Controlled Trials, Embase, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Database (CBM), VIP database for Chinese technical Periodicals, and Wanfang Database. We will choose articles published both in Chinese and English. Two reviewers will conduct the study selection, data extraction, and assessment independently. The assessment of risk of bias and data synthesis will be carried out using Review Manager Software V.5.3. RESULTS: The results will provide high-quality synthesis of current evidence for researchers in this subject area. CONCLUSION: This studys decision will provide evidence of whether external treatment of traditional Chinese medicine is an effective and safe intervention for coronavirus disease 2019 with diarrhea. REGISTRATION NUMBER: INPLASY2020110095 (DOI number: 10.37766/inplasy2020.11.0095).


Assuntos
/terapia , Diarreia/terapia , Diarreia/virologia , Medicina Tradicional Chinesa , Projetos de Pesquisa , Humanos
5.
Sci Rep ; 11(1): 470, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432090

RESUMO

Polypoidal choroidal vasculopathy (PCV) is a distinctive type of neovascular age-related macular degeneration prevalent in many Asian countries. However, there is still some controversy in how the subtypes of PCV are classified. This post-hoc study redefined the branching vascular network (BVN) and PCV subtypes through retrospective review of indocyanine green angiography (ICGA) and fluorescein angiography images from two observational studies (RENOWNED/REAL). Of the visual outcomes for each angiographic subtype and treatment pattern investigated, BVN was identified in 56.3% of PCV patients. The proportions and features of the re-defined PCV subtypes were 43.8%, 10.4%, and 45.8% for subtype A (without distinctive features of BVN), B (with BVN but no leakage), and C (with BVN and leakage), respectively. Subtype A had better visual outcomes when compared to subtype C. This possibly resulted from a better baseline visual acuity in subtype A. Moreover, combination therapy [photodynamic therapy plus anti-vascular endothelial growth factor (VEGF)] may lead to better visual improvement than mono-anti-VEGF treatment alone. This study provides the prevalence of PCV subtypes in Taiwan and may serve as a reference for PCV treatment strategies in a real-world setting, especially for the combination therapy and patients without distinctive features of BVN.

6.
J Chem Theory Comput ; 2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33459006

RESUMO

Various biochemical activities of metabolism and biosynthesis are fulfilled by redox processes with explicit electron exchange, which furnish redox enzymes with high chemical reactivity. However, theoretical investigation of a redox process, which simultaneously involves a complex electronic change at a redox metal center and conformational reorganization of the surrounding protein environment coupled to the electronic change, requires computationally conflicting approaches, highly accurate quantum chemical calculations, and long-time molecular dynamics (MD) simulations, limiting the physicochemical understanding of biological redox processes. Here, we theoretically examined a redox process of cytochrome c by means of a hybrid molecular simulation technique, which enables one to consistently treat the redox center at the ab initio quantum chemistry level of theory and the protein reorganization with long-time MD simulations on the microsecond timescale. The calculations successfully evaluated a large absolute redox potential, 4.34 eV, with errors of only 0.03 to 0.34 eV to the experimental ones without any problem-specific empirical parameters. Through the long-time MD sampling, large and nonlinear reorganization of the protein environment was unveiled and the molecular determinants for the redox potential were identified. The present ab initio approach significantly expands the applicability of theoretical investigation to biological redox systems with more electronically complicated redox centers such as polynuclear transition metal complexes.

7.
Immunity ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33453152

RESUMO

Vaccine elicitation of broadly neutralizing antibodies (bnAbs) is a key HIV-research goal. The VRC01 class of bnAbs targets the CD4-binding site on the HIV-envelope trimer and requires extensive somatic hypermutation (SHM) to neutralize effectively. Despite substantial progress, vaccine-induced VRC01-class antibodies starting from unmutated precursors have exhibited limited neutralization breadth, particularly against viruses bearing glycan on loop D residue N276 (glycan276), present on most circulating strains. Here, using sequential immunization of immunoglobulin (Ig)-humanized mice expressing diverse unmutated VRC01-class antibody precursors, we elicited serum responses capable of neutralizing viruses bearing glycan276 and isolated multiple lineages of VRC01-class bnAbs, including two with >50% breadth on a 208-strain panel. Crystal structures of representative bnAbs revealed the same mode of recognition as known VRC01-class bnAbs. Structure-function studies further pinpointed key mutations and correlated their induction with specific immunizations. VRC01-class bnAbs can thus be matured by sequential immunization from unmutated ancestors to >50% breadth, and we delineate immunogens and regimens inducing key SHM.

8.
Proc Natl Acad Sci U S A ; 118(5)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33452205

RESUMO

The outbreak of COVID-19 caused by SARS-CoV-2 has resulted in more than 50 million confirmed cases and over 1 million deaths worldwide as of November 2020. Currently, there are no effective antivirals approved by the Food and Drug Administration to contain this pandemic except the antiviral agent remdesivir. In addition, the trimeric spike protein on the viral surface is highly glycosylated and almost 200,000 variants with mutations at more than 1,000 positions in its 1,273 amino acid sequence were reported, posing a major challenge in the development of antibodies and vaccines. It is therefore urgently needed to have alternative and timely treatments for the disease. In this study, we used a cell-based infection assay to screen more than 3,000 agents used in humans and animals, including 2,855 small molecules and 190 traditional herbal medicines, and identified 15 active small molecules in concentrations ranging from 0.1 nM to 50 µM. Two enzymatic assays, along with molecular modeling, were then developed to confirm those targeting the virus 3CL protease and the RNA-dependent RNA polymerase. Several water extracts of herbal medicines were active in the cell-based assay and could be further developed as plant-derived anti-SARS-CoV-2 agents. Some of the active compounds identified in the screen were further tested in vivo, and it was found that mefloquine, nelfinavir, and extracts of Ganoderma lucidum (RF3), Perilla frutescens, and Mentha haplocalyx were effective in a challenge study using hamsters as disease model.

9.
QJM ; 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33459791

RESUMO

BACKGROUND: Recently, many studies have investigated the association between adherence to antihypertensive medication (AHM) and risk of cardiovascular disease (CVD) events for hypertensive patients; however, the results varied by different studies. AIMS: The purpose of our meta-analysis was to explore the comprehensively summarized association between AHM adherence and risk of CVD events in hypertensive patients from cohort studies. DESIGN: A dose-response meta-analysis. METHODS AND RESULTS: We conducted a systematic search in 2 databases (PubMed and Embase) from 1974 to December 15, 2019 to identify English language reports that assessed the association of AHM adherence with risk of CVD events in cohort studies. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were estimated by using a fixed- or random-effects model. Restricted cubic splines were used to evaluate the possible linear or nonlinear association. RESULTS: We included 16 cohort studies with 2,769,700 participants in the present meta-analysis. The pooled RR of CVD events was 0.66 (95% CI, 0.56-0.78, I2 =98.6%) for the highest versus lowest AHM adherence categories. We found a linear dose-response association of AHM adherence and CVD events (Pnonlinearity =0.887), each 20% increase in AHM adherence was associated with a 13% reduced risk of CVD events (RR 0.87, 95% CI 0.83-0.92, I2 =98.2%) in hypertensive patients. CONCLUSION: High AHM adherence has a protective effect on CVD events for hypertensive patients, and improving medication adherence may provide long-term CVD benefits.

10.
J Environ Manage ; 280: 111818, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360390

RESUMO

To verify how does the development of technological innovation effectively mitigate carbon dioxide (CO2) emissions in Organization for Economic Co-operation and Development (OECD) countries, this study first investigates the direct impacts and moderating effects of technological innovation, measured by the development of patents on CO2 emissions by employing a balanced panel dataset for 35 OECD countries covering 1996-2015. Also, to examine the potential heterogeneity and asymmetry, the panel quantile regression approach is utilized. The empirical results indicate that technological innovation directly reduces CO2 emissions; however, this impact is significantly heterogeneous and asymmetric across quantiles. Furthermore, through analyzing the influencing mechanism, the technological innovation affects the impacts of economic growth and renewable energy through its moderating effects. Moreover, the moderating effects of technological innovation is also heterogenous. Accordingly, the main contribution of this study is that the potential heterogeneity and asymmetry of both the direct impact and moderating effect of technological innovation on CO2 emissions in OECD countries are systematically analyzed by employing the panel quantile regression approach.


Assuntos
Dióxido de Carbono , Organização para a Cooperação e Desenvolvimento Econômico , Desenvolvimento Econômico , Invenções , Energia Renovável
11.
Biochem Biophys Res Commun ; 534: 659-665, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33239168

RESUMO

Apolipoprotein A4 (ApoA4) regulates lipid and glucose metabolism and exerts anti-inflammatory effects in atherogenesis and colitis. The present study explored the presumed protective role of ApoA4 in carbon tetrachloride (CCl4)-induced acute liver injury (ALI) in mice. The ALI model in wild type (WT), ApoA4 knock-out (ApoA4-KO) and ApoA4 transgenic (ApoA4-TG) mice was induced by a single intraperitoneal administration of CCl4. Liver and blood were harvested from mice to assess liver functions, immunohistological changes, immune cell populations and cytokine profiles. ApoA4 deficiency aggravated, and ApoA4 overexpression alleviated CCl4-inflicted liver damage by controlling levels of anti-oxidant enzymes. ApoA4 deletion increased the recruitment of monocytes/macrophages into the injured liver and upregulated the plasma levels of IL-6, TNF-α and MCP-1, but lower IL-10 and IFN-γ. ApoA4 over-expression rescued this effect and resulted in lower percentages of monocytes/macrophages and dendritic cells, the ratio of blood pro-inflammatory to anti-inflammatory monocytes and reduced plasma concentrations of IL-6, but enhanced IL-10 and IFN-γ. We propose ApoA4 as a potential new therapeutic target for the management of liver damage.

12.
Bone Marrow Transplant ; 56(1): 91-100, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32581286

RESUMO

Relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia (r/r Ph+ ALL) has an extremely poor prognosis. Chimeric antigen receptor T-cell (CART) therapy has acquired unprecedented efficacy in B-cell malignancies, but its role in the long-term survival of r/r Ph+ ALL patients is unclear. We analyzed the effect of CART on 56 adults with r/r Ph+ ALL who accepted split doses of humanized CD19-targeted CART after lymphodepleting chemotherapy. 51/56 (91.1%) achieved complete remission (CR) or CR with inadequate count recovery (CRi), including 38 patients with negative minimal residual disease (MRD) tested by bone marrow BCR-ABL1 copies. Subsequently, 30/51 CR/CRi patients accepted consolidative allogeneic haematopoietic stem cell transplantation (alloHSCT). Their outcomes were compared with those of 21/51 contemporaneous patients without alloHSCT. The 2-year overall survival (OS) and leukemia-free survival (LFS) of CR/CRi patients with alloHSCT were significantly superior to those without alloHSCT (58.9%, CI 49.8-68.0% vs. 22.7%, CI 12.7-32.7%, p = 0.005; 53.2%, CI 43.6-62.8% vs. 18.8%, CI 9.2-28.4%, p = 0.000, respectively). Multivariate analysis revealed that alloHSCT and MRD-negative post-CART were the independent prognostic factors for OS and LFS. CART therapy is highly effective for r/r Ph+ ALL patients, and consolidative alloHSCT could prolong their OS and LFS.

13.
Waste Manag ; 120: 650-658, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33243600

RESUMO

Solid waste management (SWM) is a key issue for sustainable development and environment protection, and waste collection and transportation (WCT) is one of the most important steps in managing solid waste. A well-designed SWM system with optimised location and capacity of waste transfer stations (WTSs) and final disposal facilities (FDFs) plays a critical role in waste management. However, uncertainties are inevitable in a general SWM system, which could involve in any stage of the waste management. In this paper, we propose to use the reliability analysis method to manage the uncertainties for the multiple-stage SWM system. Furthermore, an optimisation model is developed to maximise the reliability of SWM systems by optimising the allocation of waste treatment demand between facilities. We also generated an event-tree to analyse the failure mode of the whole system. Finally, a case study was undertaken in Hong Kong to demonstrate the effectiveness of the methodology. The case study results indicate that the proposed method can: (i) estate the risk level of a SWM system, (ii) provide a solution to improve the system reliability or reduce the risk level, (iii) analyse the potential contributions of different policies on the reliability index, (iv) identify the critical facilities in a SWM system.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Hong Kong , Reprodutibilidade dos Testes , Resíduos Sólidos
14.
J Crohns Colitis ; 15(1): 99-114, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-32599618

RESUMO

BACKGROUND AND AIMS: There is evidence for a disturbed necroptosis function in many inflammatory diseases, but its role in inflammatory bowel diseases [IBD] and the underlying mechanisms are unclear. Here, we studied the functional significance and molecular mechanisms of ABIN3, a ubiquitin-binding protein, in regulating the ubiquitination and activation of necroptosis in IBD. METHODS: The expression of necroptosis hallmarks and ABIN3 were assessed in inflamed samples of IBD patients, dextran sodium sulphate [DSS]-induced colitis models, and azoxymethane [AOM]/DSS models in mice. ABIN3 was overexpressed and silenced to explore its function in regulating necroptosis, inflammation, and intestinal barrier function. Immuoprecipitiation [IP] and co-IP assays were performed to investigate the cross-talk between ABIN3 and deubiquitinating enzyme A20, and the mechanisms of coordinating ubiquitination modification to regulate necroptosis. RESULTS: Excessive necroptosis is an important contributory factor towards the uncontrolled inflammation and intestinal barrier defects in IBD and experimental colitis. Blocking necroptosis by Nec-1s or GSK'872 significantly prevented cell death and alleviated DSS-induced colitis in vivo, whereas in the AOM/DSS model, necroptosis inhibitors aggravated the severity of colitis-associated colon carcinogenesis [CAC]. Mechanistically, ABIN3 is rapidly recruited to the TNF-RSC complex, which interacts and coordinates with deubiquitinating enzyme A20 to control the K63 deubiquitination modification and subsequent activation of the critical necroptosis kinase, RIPK3, to suppress necroptosis. CONCLUSIONS: ABIN3 regulates inflammatory response and intestinal barrier function by interacting with A20 and coordinating the K63 deubiquitination modification of necroptosis in IBD.

15.
Eur J Drug Metab Pharmacokinet ; 46(1): 129-139, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33140264

RESUMO

BACKGROUND AND OBJECTIVE: Rapamycin and its semi-synthetic analogues (rapalogues) are frequently used in combination with other prescribed medications in clinical settings. Although the inhibitory effects of rapalogues on cytochrome P450 enzymes (CYPs) have been well examined, the inhibition potentials of rapalogues on human esterases have not been investigated. Herein, the inhibition potentials and inhibitory mechanisms of six marketed rapalogues on human esterases are investigated. METHODS: The inhibitory effects of six marketed rapalogues (rapamycin, zotarolimus, temsirolimus, everolimus, pimecrolimus and tacrolimus) on three major esterases, including human carboxylesterases 1 (hCES1A), human carboxylesterases 2 (hCES2A) and butyrylcholinesterase (BuChE), were assayed using isozyme-specific substrates. Inhibition kinetic analyses and docking simulations were performed to investigate the inhibitory mechanisms of the rapalogues with strong hCES2A inhibition potency. RESULTS: Zotarolimus and pimecrolimus displayed strong inhibition of human hCES2A but these agents did not inhibit hCES1A or BuChE. Further investigation demonstrated that zotarolimus could strongly inhibit intracellular hCES2A in living HepG2 cells, with an estimated IC50 value of 4.09 µM. Inhibition kinetic analyses revealed that zotarolimus inhibited hCES2A-catalyzed fluorescein diacetate hydrolysis in a mixed manner, with the Ki value of 1.61 µM. Docking simulations showed that zotarolimus could tightly bind on hCES2A at two district ligand-binding sites, consistent with its mixed inhibition mode. CONCLUSION: Our findings demonstrate that several marketed rapalogues are potent and specific hCES2A inhibitors, and these agents can serve as leading compounds for the development of more efficacious hCES2A inhibitors to modulate the pharmacokinetic profiles and toxicity of hCES2A-substrate drugs (such as the anticancer agent irinotecan).

16.
Biochim Biophys Acta Mol Cell Res ; 1868(1): 118895, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33096144

RESUMO

MutT Homolog 1 (MTH1) is a mammalian 8-oxodGTPase for sanitizing oxidative damage to the nucleotide pool. Nudix type 5 (NUDT5) also sanitizes 8-oxodGDP in the nucleotide pool. The role of MTH1 and NUDT5 in non-small-cell lung cancer (NSCLC) progression and metastasis remains unclear. In the present study, we reported that MTH1 and NUDT5 were upregulated in NSCLC cell lines and tissues, and higher levels of MTH1 or NUDT5 were associated with tumor metastasis and a poor prognosis in patients with NSCLC. Their suppression also restrained tumor growth and lung metastasis in vivo and significantly inhibited NSCLC cell migration, invasion, cell proliferation and cell cycle progression while promoting apoptosis in vitro. The opposite effects were observed in vitro following MTH1 or NUDT5 rescue. In addition, the upregulation of MTH1 or NUDT5 enhanced the MAPK pathway and PI3K/AKT activity. Furthermore, MTH1 and NUDT5 induce epithelial-mesenchymal transition both in vitro and in vivo. These results highlight the essential role of MTH1 and NUDT5 in NSCLC tumor tumorigenesis and metastasis as well as their functions as valuable markers of the NSCLC prognosis and potential therapeutic targets.

17.
Cancer Lett ; 497: 137-153, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33080309

RESUMO

Arsenic, a human carcinogen, causes various human cancers, including those of the skin, lung, and liver. Hepatocellular carcinomas (HCCs), which have high mortality, are common malignancies worldwide. Tumor-associated macrophages (TAMs), which are considered to be similar to M2-polarized macrophages, promote tumor invasion and progression. Small non-coding RNAs (miRNAs) regulate expression of genes involved in progression of various malignancies. Extracellular vesicles (EVs), as mediators of cell communication, pass specific miRNAs directly from TAMs to tumor cells, promoting tumor pathogenesis and metastasis. In HCCs, large tumor suppressor kinase 1 (LATS1), functions as a tumor suppressor. However, the molecular mechanism by which miRNA modulates LATS1 expression in HCCs remains unclear. The results show that exposure to arsenite, increased miR-15b levels and induced M2 polarization of THP-1 cells. Elevated levels of miR-15b were transferred from arsenite-treated-THP-1 (As-THP-1) cells to HCC cells via miR-15b in EVs inhibited activation of the Hippo pathway by targeting LATS1, and was involved in promoting the proliferation, migration, and invasion of HCC cells. In conclusion, miR-15b in EVs from As-THP-1 cells is transferred to HCC cells, in which it targets and downregulates LATS1 expression and promotes the proliferation, migration, and invasion of HCC cells.

18.
Waste Manag ; 119: 1-10, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33032153

RESUMO

Disaster waste clean-up after large disasters is one of the core activities at the recovery stage of disaster management, which aims to restoring the normal functioning of the disaster affected area. In this paper we considered a waste clean-up system consists of (i) demolition operation, (ii) collection of waste from customer nodes to temporary disaster waste management sites (TDWMSs), (iii) processing at TDWMSs, and (iv) transportation of the waste to final disposal sites in the recovery of disasters. A multi-objective mixed integer programming model is developed to minimise the total clean-up cost and time. Three different approaches are developed to solve the problem, which are tested with artificial instances and a real case study. Results of artificial instances indicate that the models developed can be used to obtain close to optimal solutions within an acceptable computing time. Results of the case study can facilitate the decision-makers to develop the waste clean-up with minimised total cost and clean-up time by selecting the right location of TDWMSs and setting up the proper waste clean-up schedule.


Assuntos
Desastres , Eliminação de Resíduos , Gerenciamento de Resíduos , Transportes
19.
Sci Total Environ ; 754: 142151, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916496

RESUMO

River damming has seen a growing trend in demand worldwide and the impounded reaches are considered hotspots of greenhouse gas emissions. However, it remains unclear how the spatial distribution of C-gas in sediments and methane (CH4) emissions of dammed tributary changes under different operation periods of the Three Gorges reservoir (TGR). We measured CH4 and carbon dioxide (CO2) concentrations in sediment and CH4 emissions from a dammed river of the TGR, and evaluated the effect of damming on the spatial variability of carbon in the sediment and on CH4 flux. It was found that damming led to a distinct spatial pattern of total organic carbon (TOC) in the sediment, which resulted in higher CH4 and CO2 in upstream sediment compared to the downstream. During the TGR impounding period, the upstream CH4 diffusive flux (0.253-0.427 mg m-2 h-1) across the water-air interface was higher than in the downstream (0.093 mg m-2 h-1), which was consistent with the spatial variation of CH4 in the sediments. However, the CH4 emission was predominantly by ebullition and the flux in the downstream (169.173 mg m-2 h-1) was significantly higher than upstream (12.23-123.05 mg m-2 h-1) in the discharging period. This can be attributed to a sharp increase in TOC in downstream sediment due to riparian zone soil erosion on both banks, which was caused by periodic large fluctuation in the water level, and a shallow water depth in the downstream. This study adds to our understanding of effects of the TGR's operation on CH4 emissions from a dammed tributary and suggests that the water level fluctuation of tributaries which has direct influence on ebullition and methane oxidation caused by manipulation of the TGR should not be overlooked.

20.
Exp Cell Res ; 398(1): 112401, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33253711

RESUMO

The ubiquitin-like protein FAT10 and the hexokinase protein HK2 play vital regulatory roles in several cellular processes. However, the relationship between these two proteins and their role in the pathogenesis of bladder cancer are not well understood. Here, we found that FAT10 and HK2 protein levels were markedly higher in bladder cancer tissues than in normal adjacent tissues. In addition, RNAi-mediated silencing of FAT10 led to reduced HK2 levels and suppressed bladder cancer progression in vivo and in vitro. The results of our in vivo and in vitro experiments revealed that HK2 is critical for FAT10-mediated progression of bladder cancer. The current study demonstrated that FAT10 enhanced the progression of bladder cancer by positively regulating HK2 via the EGFR/AKT pathway. Based on our findings, FAT10 is believed to stabilize EGFR expression by modulating its degradation and ubiquitination. The results of the current study indicate that there is a correlation between FAT10 and HK2 in the progression of bladder cancer. In addition, we identified a new pathway that may be involved in the regulation of HK2. These findings implicate dysfunction of the FAT10, EGFR/AKT, and HK2 regulatory circuit in the progression of bladder cancer.

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