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1.
J Colloid Interface Sci ; 606(Pt 1): 719-727, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34416461

RESUMO

The preparation of hollow materials is one of the most feasible ways to obtain efficient electromagnetic wave (EMW) absorbers. Herein, using the copper-based metal-organic frameworks (Cu-MOF-74) as templates, hollow copper-based sulfides with various morphologies (rod-like, cubic, and dodecahedral) were designed and synthesized. The outer Cu2S and/or Cu31S16 shell possesses excellent electronic conductivity and abundant heterogeneous interfaces, while the inner hollow cavity endows the absorbers with lightweight characteristics and good impedance matching according to the Maxwell-Garnett (MG) theory. Accordingly, the effective absorption bandwidth reaches 6.2 GHz at 2.3 mm with 20 wt% filler loading, exhibiting superior performance compared with the vast majority of previous MOFs derived absorbers. Furthermore, our study can serve a guide to construct hollow structured nanocomposites to tune electromagnetic parameters and strengthen EMW absorption properties.

2.
Sci Total Environ ; 806(Pt 1): 150498, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563908

RESUMO

Sediment microbial communities play critical roles in the health of fish and the biogeochemical cycling of elements in aquaculture ecosystems. However, the response of microbial communities to temporal and spatial variations in interconnected aquaculture pond and ditch systems remains unclear. In this study, 61 sediment bacterial samples were collected over one year from 11 sites (including five ponds and six ditches) in a 30-year-old fish aquaculture farm. The 16S rRNA approach was used to determine the relative abundances of microbial communities in the sediment samples. The relationships among nutrients, heavy metals, and abundant microorganisms were analyzed. Our results showed that Proteobacteria, Bacteroides and Chloroflexi were the predominant phyla in the sediments of aquaculture pond, with average abundances of 36.33%, 18.60%, and 14.58%, respectively. The microbial diversity in aquaculture sediments was negatively correlated (P < 0.05) with the concentrations of total nitrogen and total phosphorus in sediments, indicating that the microbial diversity is highly associated with the remediation of nutrients in sediments. The sediment samples with high similarities were discovered by the t-distributed stochastic neighbor embedding (t-SNE) method. The site-specific correlations between specific microorganisms and heavy metals were explored. The network analysis revealed that the microbial diversities in aquaculture ponds were more stable than that in aquaculture ditches. The network analysis also illustrated that the microbial genera with low relative abundances may become key groups of microbial communities in sediment ecosystems. Our work deepens the understanding of the relationships between microbial communities and the spatiotemporal characteristics of surface water and sediments in aquaculture farms.

3.
Cancer Lett ; 524: 82-90, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34626692

RESUMO

Long non-coding RNAs (lncRNAs) play important roles in cancer development and progression; however, their contributions to gastric cancer metastasis remain largely unknown. By lncRNA microarray screening, our study showed that 453 lncRNAs are dysregulated in gastric cancer tissues with or without lymph node metastasis, of which lnc-LEMGC ranks as one of the most significantly downregulated lncRNAs. Lnc-LEMGC inhibited cell migration and invasion both in vitro and in vivo, by combining with protein DNA-PKcs. Importantly, nucleotides 1300-1800 of lnc-LEMGC prevented DNA-PKcs phosphorylation of serine 2056 and partially abrogated the effects of downstream effectors, ErbB1, SRC and protein tyrosine kinase 2 (FAK), in the epidermal growth factor receptor (EGFR) pathway. The results of this study extend our knowledge of lncRNA's molecular mechanisms, in which lnc-LEMGC functions by directly suppressing the phosphorylation of its combined protein DNA-PKcs and inactivating the DNA-PKcs downstream EGFR signaling.

4.
Sci Total Environ ; 803: 149964, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34481162

RESUMO

Energy conversion and utilization of sewage sludge (SS) and lignocellulosic biomass are an important measure to deal with environmental pollution and resource utilization. Addressing the waste by-product in a clean way is essential. In this study, solid char fuel (hydrochar) was obtained through co-hydrothermal carbonization of SS with pinewood sawdust (PS), and methane gas was obtained through anaerobic digestion (AD) of hydrothermal carbonization wastewater (HTCWW). The energy conversion performance of the feedstock organics under different HTC conditions (temperature of 160 °C, 220 °C, and 280 °C; reaction time of 0, 2, and 4 h; feedstock liquid-solid mass ratio of 4:1, 10:1, and 16:1), and the mass and energy yields of hydrochar and methane and their influencing factors were emphasized. More than 60% of the energy in SS and PS can be recovered by coupling the HTC-AD process. With the increase in hydrothermal reaction temperature and reaction time, the mass yield of hydrochar decreased, but the higher heating value increased. The maximum energy yield of hydrochar was 86.47% under the HTC temperature of 160 °C, liquid-solid ratio of 10:1, and reaction time of 2 h. The HTCWW obtained at a lower temperature (160 °C) showed the highest cumulative methane yield of 304.16 mL-CH4/g-COD.


Assuntos
Pinus , Esgotos , Anaerobiose , Carbono , Temperatura , Águas Residuárias
5.
Oncol Lett ; 22(6): 842, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34733361

RESUMO

[This corrects the article DOI: 10.3892/ol.2017.5886.].

6.
Chemosphere ; : 133007, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34826443

RESUMO

Photocatalysis is an effective method for the removal of formaldehyde (HCHO), and high-efficiency visible-light-driven photocatalysts were urgently required. Herein, oxygen vacancies (OVs) and nano copper oxides (CuOx) synergistically modified TiO2 (CuOx/TiO2-x) photocatalysts were synthesized by one-step hydrothermal followed by impregnation method. The photocatalytic decomposition of HCHO reached 100% at initial concentration of 180 ppm under relative humidity (RH) = 60% by 0.1g CuOx/TiO2-x in 150 min visible light irradiation. Characterization results explored the complementary effect of OVs and CuOx systematically. The OVs increased the separation efficiency of photogenerated charge carriers and act as adsorption/active sites in HCHO photocatalytic oxidation. The moisture and O2 were adsorbed and actived by OVs to generate reactive oxygen species (ROS). After doped CuOx on the surface of TiO2-x, the photoexcited electrons in Cu2O could transfer to the conduction band (CB) of TiO2-x and the photoexcited electrons of TiO2-x could be captured by Cu nanoparticles. Therefore, more ROS were generated due to the synergistic effect of OVs and CuOx. The In-situ Fourier transform infrared (in-situ FTIR) measurements show the hydroxyl radical (•OH) was the dominant radical in HCHO photocatalytic oxidation, while •O2- could also upgrade the photodegradation efficiency of HCHO. Furthermore, the stability tests showed the degradation efficiency of HCHO still reached 90% after five recycles, indicating that CuOx/TiO2-x nanocomposites displayed a stable and high photoactivity in volatile organic compounds (VOCs) decomposition.

7.
BMC Pulm Med ; 21(1): 364, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772390

RESUMO

BACKGROUND: The inflammatory phenotypes of asthma predict the treatment response and prognosis. The phenotype distributions differ depending on the geographical region. This study aimed to assess the distribution of different inflammatory phenotypes among asthma patients in Jilin Province, China. METHODS: A total of 255 patients with asthma were recruited from Jilin Province, China for this cross-sectional study. Each patient underwent sputum induction following clinical assessment and peripheral blood collection. Inflammatory phenotypes were classified according to the inflammatory cell counts in the sputum. RESULTS: Paucigranulocytic asthma (PGA) was the most common inflammatory phenotype (52.2%), followed by eosinophilic asthma (EA, 38.3%), mixed granulocytic asthma (MGA, 5.2%), and neutrophilic asthma (NA, 4.3%). NA was more common among patients over 45 years old and those who were treated with higher doses of inhaled corticosteroids (ICS), but was less common following antibiotics treatment (p < 0.05). The proportion of patients with EA decreased as the ICS treatment dose and time increased (p = 0.038). Patients with uncontrolled asthma had higher numbers of sputum eosinophils and neutrophils (p < 0.05). Patients with severe asthma had a higher percentage of sputum neutrophils (p < 0.05). A greater proportion of patients with NA had severe asthma (60%) compared to those with EA (18.2%) (p = 0.016). CONCLUSIONS: The most common asthma inflammatory cell phenotype in Jilin Province, China is PGA, followed by EA, MGA, and NA. The low prevalence of NA in Jilin Province compared to other countries and also other regions in China might be due to excessive antibiotic use and irregular ICS treatment in this region.

8.
Nat Commun ; 12(1): 6551, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772944

RESUMO

The enantioselective construction of C-CF2R (R: alkyl or fluoroalkyl) bonds has attracted the attention of synthetic chemists because of the importance of chiral fluorinated compounds in life and materials sciences. Catalytic asymmetric fluoroalkylation has mainly been realized under organocatalysis and Lewis acid catalysis, with substrates limited to carbonyl compounds. Few examples using transition-metal catalysis exist, owing to side reactions including decomposition and isomerization of fluoroalkylating reagents. Herein we report umpolung asymmetric difluoroallylation of hydrazones with 3-bromo-3,3-difluoropropene (BDFP) under palladium catalysis. Difluoroallylation products having quaternary chiral carbon centers are afforded in good yields with high α/γ- and enantioselectivities. The usefulness of the reaction products is demonstrated and an inner-sphere mechanism of the reaction is proposed. The use of chiral N-heterocyclic carbene as ligand is the key for the selectivities as well as the productivity of the reaction.

9.
BMC Cancer ; 21(1): 1214, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34773999

RESUMO

BACKGROUND: Neoadjuvant therapy can lead to different tumor regression grades (TRG) in rectal cancer after neoadjuvant therapy. The purposes of this study are to investigate the relationships among TRG, pathologic complete response (pCR) and long-term survival, on the basis of reconstructed individual patient data (IPD). METHODS: The PubMed, Embase, Ovid and Cochrane CENTRAL databases were searched. The primary endpoint was to evaluate the survival landscape of different TRGs after neoadjuvant therapy and the secondary endpoint was to evaluate the associations between pCR and survival. IPD were reconstructed with Kaplan-Meier curves. RESULTS: The 10-year overall survival (OS) and 5-year disease-free survival (DFS) were clearly higher in the pCR group than in the non-pCR (npCR) group (80.5% vs. 48.3, 90.1% vs. 69.8%). Furthermore, the OS and DFS increased with improvement in tumor regression after neoadjuvant therapy. According to the IPD, the pCR group had longer OS (HR = 0.240, 95% CI = 0.177-0.325, p < 0.001) and DFS (HR = 0.274, 95% CI = 0.205-0.367, p < 0.001) than the npCR group. Better tumor regression was associated with better survival outcomes (p < 0.005). Direct calculation of published HR values yielded similar results. CONCLUSIONS: Our results indicate a positive relationship between better tumor regressions and improved survival benefits among the npCR group and patients with rectal cancer achieving pCR had much longer OS and DFS than patients achieving npCR, presenting a survival landscape of different TRGs and pCR in rectal cancer after neoadjuvant therapy.

10.
Nat Nanotechnol ; 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34782776

RESUMO

The growth of wafer-scale single-crystal two-dimensional transition metal dichalcogenides (TMDs) on insulating substrates is critically important for a variety of high-end applications1-4. Although the epitaxial growth of wafer-scale graphene and hexagonal boron nitride on metal surfaces has been reported5-8, these techniques are not applicable for growing TMDs on insulating substrates because of substantial differences in growth kinetics. Thus, despite great efforts9-20, the direct growth of wafer-scale single-crystal TMDs on insulating substrates is yet to be realized. Here we report the successful epitaxial growth of two-inch single-crystal WS2 monolayer films on vicinal a-plane sapphire surfaces. In-depth characterizations and theoretical calculations reveal that the epitaxy is driven by a dual-coupling-guided mechanism, where the sapphire plane-WS2 interaction leads to two preferred antiparallel orientations of the WS2 crystal, and sapphire step edge-WS2 interaction breaks the symmetry of the antiparallel orientations. These two interactions result in the unidirectional alignment of nearly all the WS2 islands. The unidirectional alignment and seamless stitching of WS2 islands are illustrated via multiscale characterization techniques; the high quality of WS2 monolayers is further evidenced by a photoluminescent circular helicity of ~55%, comparable to that of exfoliated WS2 flakes. Our findings offer the opportunity to boost the production of wafer-scale single crystals of a broad range of two-dimensional materials on insulators, paving the way to applications in integrated devices.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34783150

RESUMO

Intramolecular noncovalent interactions (INIs) have served as a powerful strategy for accessing organic semiconductors with enhanced backbone planarity and charge transport properties. Herein, we apply the INI strategy for developing dopant-free hole-transporting materials (HTMs) by constructing two small-molecular HTMs featuring an INI-integrated backbone for high-performance perovskite solar cells (PVSCs). Upon incorporating noncovalent S···O interaction into their simple-structured backbones consisting of a bithiophene core and two triphenylamine ends, the resulting HTMs, BTORA and BTORCNA, showed self-planarized backbones, tuned energy levels, enhanced thermal properties, appropriate film morphology, and effective defect passivation. More importantly, the high film crystallinity enables the materials with substantial hole mobilities, thus rendering them as promising dopant-free HTMs. Consequently, the BTORCNA-based inverted PVSCs delivered a remarkable power conversion efficiency of 21.10% with encouraging long-term device stability, significantly outperforming the devices based on BTRA without S···O interaction (18.40%). This work offers a general and practical approach to designing charge transporting layers with high intrinsic mobilities for high-performance PVSCs.

13.
Opt Express ; 29(21): 33679-33693, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809175

RESUMO

This study presents a partially coherent illumination based (PCI-based) SIM apparatus for dual-modality (phase and fluorescent) microscopic imaging. The partially coherent illumination (PCI) is generated by placing a rotating diffuser on a monochromatic laser beam, which suppresses speckle noise in the dual-modality images and endows the apparatus with sound sectioning capability. With this system, label-free quantitative phase and super-resolved/sectioned fluorescent images can be obtained for the same sample. We have demonstrated the superiority of the system in phase imaging of transparent cells with high endogenous contrast and in a quantitative manner. In the meantime, we have also demonstrated fluorescent imaging of fluorescent beads, rat tail crosscut, wheat anther, and hibiscus pollen with super-resolution and optical sectioning. We envisage that the proposed method can be applied to many fields, including but not limited to biomedical, industrial, chemistry fields.

14.
Chem Commun (Camb) ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812448

RESUMO

We report here a catalytically active nano covalent organic framework [COF(Fe)] with high drug loading capacity for reversing tumor multidrug resistance (MDR). The Fe catalytic sites in COF(Fe) could convert intracellular overexpressed H2O2 into highly reactive ˙OH to induce oxidation stress and down-regulate MDR protein. Therefore, COF(Fe) could enhance the intracellular drug accumulation to overcome MDR, which was demonstrated both in vitro and in vivo.

16.
Cancer Gene Ther ; 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34799724

RESUMO

N6-methyladenosine (m6A) RNA methylation and its associated methyltransferase METTL3 play an important role in tumorigenesis of a series of tumors. However, dysregulation of METTL3 in gallbladder cancer (GBC) remains obscure. Here, we showed that upregulated METTL3 level predicted poor prognosis and correlated with increased lymphatic metastasis and high TNM stage. Functionally, we found that METTL3 could promote cell proliferation, invasion, and migration of GBC-SD and NOZ cells. Mechanistically, we revealed the METTL3-mediated m6A-modification profile in GBC cells and identified DUSP5 as the downstream gene of METTL3. METTL3 promoted the degradation of DUSP5 mRNA in a YTHDF2-dependent manner. Rescue assays showed that downregulation of DUSP5 could attenuate the knockdown METTL3-mediated inhibition of cell proliferation, invasion, and migration of GBC-SD and NOZ cells. Thus, our finding shows that elevated METTL3 expression contributes to tumor aggression in GBC, suggesting that METTL3 is a possible prognostic predictor and therapeutic target against GBC.

17.
Calcif Tissue Int ; 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800131

RESUMO

Paget's disease of bone (PDB) is a rare metabolic bone disorder, which is extremely rare in Asian population. This study aimed to investigate the phenotypes and the pathogenic mutations of woman with early-onset PDB. The clinical features, bone mineral density, x-ray, radionuclide bone scan, and serum levels of alkaline phosphatase (ALP), procollagen type 1 N-terminal propeptide (P1NP), and ß-carboxy-terminal cross-linked telopeptide of type 1 collagen (ß-CTX) were measured in detail. The pathogenic mutations were identified by whole-exon sequencing and confirmed by Sanger sequencing. We also evaluated the effects of intravenous infusion of zoledronic acid on the bones of the patient and summarized the phenotypic characteristics of reported patients with mutation at position 155 of the valosin-containing protein (VCP). The patient only exhibited bone pain as the initial manifestation with vertebral compression fracture and extremely elevated ALP, P1NP, and ß-CTX levels; she had no inclusion body myopathy and frontotemporal dementia. The missense mutation in exon 5 of the VCP gene (p.Arg155His) was identified by whole-exome sequencing and further confirmed by Sanger sequencing. No mutation in candidate genes of PDB, such as SQSTM1, CSF1, TM7SF4, OPTN, PFN1, and TNFRSF11A, were identified in the patient by Sanger sequencing. Rapid relief of bone pain and a marked decline in ALP, P1NP, and ß-CTX levels were observed after zoledronic acid treatment. Previously reported patients with VCP missense mutation at position 155 (R155H) always had myopathy, frontotemporal dementia, and PDB, but the patient in this study exhibited only PDB. This was the first report of R155H mutation-induced early-onset in the VCP gene in Asian population. PDB was the only manifestation having a favorable response to zoledronic acid treatment. We broadened the genetic and clinical phenotype spectra of the VCP mutation.

18.
BMC Cardiovasc Disord ; 21(1): 529, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749678

RESUMO

BACKGROUND: Neutrophil-lymphocyte ratio (NLR) is a valuable indicator for evaluating inflammation and adverse outcomes after cardiac surgery. The objective of this study was to evaluate the association of perioperative NLR with clinical outcomes in infants undergoing congenital heart surgery with cardiopulmonary bypass. METHODS: We performed a retrospective review of 424 consecutive infants (≤ 1 year) undergoing cardiac surgery between January 2019 and September 2019. Neonates (≤ 28 days) and patients with incomplete NLR data were excluded. The study endpoint was a composite of poor outcomes after surgery. We assess the correlation between perioperative NLR and clinical outcomes. A receiver operating characteristic curve and multivariable logistic regression were applied to identify the prognosis performance of postoperative NLR for poor outcomes. RESULTS: A total of 68 (16%) infants experienced at least one of the poor outcomes. Postoperative NLR on the third day after the surgery showed the best prognostic significance (AUC = 0.763, 95%CI 0.700-0.826) among perioperative period, with a cut-off value of 2.05. Postoperative NLR was also strongly correlated with mechanical ventilation time, length of ICU and hospital stay (p < 0.001). Multivariable logistic regression revealed that elevated postoperative NLR (OR 3.722, 95%CI 1.895-7.309, p < 0.001) was an independent risk factor for poor outcomes in infants after cardiac surgery. CONCLUSIONS: Postoperative NLR was correlated with increased mechanical ventilation time, length of ICU and hospital stay. Elevated postoperative NLR was an independent predictor for poor outcomes after cardiac surgery in infants.

19.
Adv Mater ; : e2103620, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34808008

RESUMO

The wettability of graphene remains controversial owing to its high sensitivity to the surroundings, which is reflected by the wide range of reported water contact angle (WCA). Specifically, the surface contamination and underlying substrate would strongly alter the intrinsic wettability of graphene. Here, we investigate the intrinsic wettability of graphene by measuring WCA on suspended, superclean graphene membrane using environmental scanning electron microscope. An extremely low WCA with an average value ∼ 30o was observed, confirming the hydrophilic nature of pristine graphene. This high hydrophilicity originates from the charge transfer between graphene and water molecules through H-π interaction. Our work provides a deep understanding of the water-graphene interaction and opens up a new way for measuring the surface properties of 2D materials. This article is protected by copyright. All rights reserved.

20.
Appl Intell (Dordr) ; : 1-15, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-34764591

RESUMO

Knowledge in the source domain can be used in transfer learning to help train and classification tasks within the target domain with fewer available data sets. Therefore, given the situation where the target domain contains only a small number of available unlabeled data sets and multi-source domains contain a large number of labeled data sets, a new Multi-source Fast Transfer Learning algorithm based on support vector machine(MultiFTLSVM) is proposed in this paper. Given the idea of multi-source transfer learning, more source domain knowledge is taken to train the target domain learning task to improve classification effect. At the same time, the representative data set of the source domain is taken to speed up the algorithm training process to improve the efficiency of the algorithm. Experimental results on several real data sets show the effectiveness of MultiFTLSVM, and it also has certain advantages compared with the benchmark algorithm.

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