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2.
Nat Commun ; 12(1): 53, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397907

RESUMO

With the advent of the big data era, applications are more data-centric and energy efficiency issues caused by frequent data interactions, due to the physical separation of memory and computing, will become increasingly severe. Emerging technologies have been proposed to perform analog computing with memory to address the dilemma. Ferroelectric memory has become a promising technology due to field-driven fast switching and non-destructive readout, but endurance and miniaturization are limited. Here, we demonstrate the α-In2Se3 ferroelectric semiconductor channel device that integrates non-volatile memory and neural computation functions. Remarkable performance includes ultra-fast write speed of 40 ns, improved endurance through the internal electric field, flexible adjustment of neural plasticity, ultra-low energy consumption of 234/40 fJ per event for excitation/inhibition, and thermally modulated 94.74% high-precision iris recognition classification simulation. This prototypical demonstration lays the foundation for an integrated memory computing system with high density and energy efficiency.

3.
Anticancer Drugs ; Publish Ahead of Print2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33394687

RESUMO

Evodiamine (Evo), a quinazoline alkaloid and one of the most typical polycyclic heterocycles, is mainly isolated from Evodia rugulosa. Vasculogenic mimicry (VM) is a newly identified way of angiogenesis during tumor neovascularization, which is prevalent in a variety of highly invasive tumors. The purpose of this study was to investigate the effect and mechanism of Evo on VM in human colorectal cancer (CRC) cells. The number of VM structures was calculated by the three-dimensional culture of human CRC cells. Wound-healing was used to detect the migration of HCT116 cells. Gene expression was detected by reverse transcription-quantitative PCR assay. CD31/ PAS staining was used to identify VM. Western blotting and immunofluorescence were used to detect protein levels. The results showed that Evo inhibited the migration of HCT116 cells, as well as the formation of VM. Furthermore, Evo reduced the expression of hypoxia-inducible factor 1-alpha (HIF-1α), VE-cadherin, VEGF, MMP2, and MMP9. In a model of subcutaneous xenotransplantation, Evo also inhibited tumor growth and VM formation. Our study demonstrates that Evo could inhibit VM in CRC cells HCT116 and reduce the expression of HIF-1α, VE-cadherin, VEGF, MMP2, and MMP9.

4.
Cell Reprogram ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33400599

RESUMO

To investigate the feasibility of ß-tricalcium phosphate (TCP)/gelatine scaffold combined with allogeneic adipose-derived stem cells (ASCs) to repair hole shape defect, third-passage ASCs were seeded onto composite scaffolds to prepare an ASC-ß-TCP/gelatine tissue-engineered bone to pack into the rabbit cavernous bone defects of experimental groups. In animal models, the bone defect area was completely filled and difficult to recognize in the experimental group at 12 weeks post-surgery by gross observation and radiographic examination. The average bone mineral density value of them was higher than that of the control group. Because of the biocompatibility with allogenic ASCs and the osteoconductivity of ß-TCP/gelatine scaffolds, ß-TCP/gelatine is suitable as a plastic scaffold for the ASC-seeded tissue-engineered bone to repair cavernous defects.

5.
J Econ Entomol ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33438024

RESUMO

With significant surge of international trade in recent decades, increasingly more arthropod species have become established outside their natural range of distribution, causing enormous damage in their novel habitats. However, whether a species can colonize its new environment depends on its ability to overcome various barriers which may result in establishment failure, such as inbreeding depression and difficulty to find mates. Here, we used a haplodiploid pest, Tetranychus ludeni Zacher (Acari: Tetranychidae), which is native to Europe but now cosmopolitan, to investigate whether its reproductive strategies have facilitated its invasion success, providing knowledge to develop programs for prediction and management of biological invasions. We show that inbreeding had no negative influence on female reproductive outputs and longevity over 11 successive generations, allowing mother-son and brother-sister mating to occur at the invasion front without adverse consequences in fitness. Virgin females produced maximum number of sons in their early life to ensure subsequent mother-son mating but later saved resources to prolong longevity for potential future mating. Females maximized their resource allocation to egg production immediately after mating to secure production of maximum number of both daughters and sons as early as possible. Furthermore, mated females with mating delay increased proportion of daughters in offspring produced to compensate the loss of production of daughters during their virgin life. We suggest that the lack of inbreeding depression in successive generations and the ability to adjust resource allocations depending whether and when mating occurs may be the key features that have facilitated its invasion success.

6.
J Clin Lab Anal ; : e23693, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33389794

RESUMO

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is the most common category of non-Hodgkin lymphoma (NHL). However, the underlying molecular mechanism of DLBCL remains unclear. METHODS: Real-time PCR and Western blot analysis were performed to assess the expression of ubiquitin-specific peptidase 21 (USP21) or enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2). CCK8 assay and cell death staining were carried out to examine the role of USP21 in cell proliferation and cell death, respectively. RESULTS: We found that the deubiquitinase USP21 was highly expressed in the DLBCL lymphoid tissue. The expression of USP21 promoted DLBCL cell proliferation, while it had no obvious effect on cell death. In addition, we found that USP21 regulated cell proliferation via cysteine 221, the catalytic site of USP21. Furthermore, we identified that USP21 could stabilize EZH2, a protein required for germinal center formation and lymphoma formation. CONCLUSION: The deubiquitinase USP21 promotes cell proliferation by maintaining the EZH2 protein level in DLBCL.

7.
Res Social Adm Pharm ; 17(1): 1819-1824, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32249102

RESUMO

BACKGROUND: The novel coronavirus pneumonia (COVID-19), which was first detected in Wuhan City, has now became a pandemic that affecting patients around the world. Particularly, the community patient population are at high risk of infection and are facing potential failure of proper medication use during the pandemic. OBJECTIVE: To discuss community pharmacists' role and the content of pharmaceutical care (PC) during the novel coronavirus pandemic to promote effective prevention and control and safe drug use of the community patient population. METHOD: Collect and summarize the experience Chinese community pharmacies gained from providing pharmacy services during the COVID-19 outbreak, and taking patients' PC needs into consideration, analyze and discuss the methods and strategies that community pharmacies and pharmacists shall use to provide PC during the pandemic. RESULTS: Community pharmacy management teams shall support PC services by providing adequate supply of COVID-19 related medications and preventative products, following environment regulations, and providing sufficient staff trainings. Pharmacists shall use various approaches to provide PC services in drug dispensing, consulting and referrals, chronic disease management, safe use of infusions, patient education, home care guidance and psychological support to promote the COVID-19 pandemic control and ensure safe medication use of community patients during the pandemic. CONCLUSION: PC services in communities during the COVID-19 shall possess different properties due to disease characteristics and related change in patients' need. Community pharmacies shall work as a strong supporter of patient's medication and protective equipment supply. Community pharmacists shall be prepared to provide skilled and effective PC services for community patient population to ensure medication safety and promote the overall COVID-19 pandemic control.


Assuntos
/prevenção & controle , Serviços Comunitários de Farmácia/organização & administração , Farmacêuticos/organização & administração , /epidemiologia , China , Necessidades e Demandas de Serviços de Saúde , Humanos , Equipamento de Proteção Individual/provisão & distribução , Papel Profissional
8.
Transl Stroke Res ; 12(1): 49-56, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32601933

RESUMO

A significant portion of ischemic stroke is on account of emboli caused by fibrous cap rupture of vulnerable plaque with intraplaque neovascularization as a significant triggering factor to plaque vulnerability. Contrast-enhanced ultrasound (CEUS) could offer detailed information on plaque surface and intraplaque microvascular. This study aims to comprehensively assess the value of CEUS for the detection of plaque rupture and neovascularization in histologically verified plaques that had been removed from the patients who had undergone carotid endarterectomy (CEA). Fifty-one consecutive subjects (mean age, 67.0 ± 6.5 years; 43 [84.3%] men) scheduled for CEA were recruited. Standard ultrasound and CEUS were performed prior to surgery. Based on the direction of the contrast agents that diffuse within the plaques, plaques were divided as "inside-out" direction (contrast agents diffuse from the artery lumen towards the inside of the plaque) and non-inside-out direction. Plaque enhancement was assessed by using a semi-quantitative grading scale (grade 1: no enhancement; grade 2: moderate enhancement; grade 3: extensive enhancement). Plaques were evaluated for histopathologic characteristics according to Oxford Plaque Study (OPS) standard postoperative. Intraplaque neovascularization as manifested by the appearance of CD34-positive microvessels was characterized in terms of microvessel density (MVD), microvessel area (MVA), and microvessel shape (MVS). In 51 plaques, the sensitivity, specificity, positive, and negative predictive values of contrast agent inside-out direction diffusion for the detection of plaque fibrous cap rupture were 87.5%, 92.6%, 91.3%, and 89.3%, respectively. The incidence of cap rupture was significantly higher in contrast agent inside-out direction diffusion than non-inside-out direction diffusion (73.9% vs 25.0%, p < 0.001), and inside-out direction diffusion did exhibit higher frequency of vulnerable plaques (OPS grades 3-4) (95.7% vs 53.6%, p = 0.001). Multivariate logistic regression analysis revealed the contrast agent inside-out direction diffusion as an independent correlate to plaque rupture (OR 8.5, 95% CI 2.4-30.1, p = 0.001). With increasing plaque enhancement, plaque MVD (p < 0.001), plaque MVA (p = 0.012), and percentage of highly irregular-shaped microvessels increased (p < 0.001). Contrast agent inside-out direction diffusion could indicate plaque rupture. The increase in plaque enhancement paralleled increased, larger, and more irregular-shaped microvessels, which may suggest an increased risk of plaque vulnerability.

9.
J Craniofac Surg ; 32(1): e19-e20, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32858607

RESUMO

OBJECTIVES: The aim of this study was to study and explore the genetic mechanism of familial meningiomas through 3 cases of familial tuberculum sellae meningioma. METHODS: A retrospective analysis of clinical data of 3 cases of familial tuberculum sellae meningioma patients, and the pathological results of types and immunohistochemical results of the 3 patients were compare. REULTS: Three cases of postoperative pathology were meningiomas (mixed type), immunohistochemical examination showed that Vimentin, epithelial membrain antigen , and Ki67 were positive. CONCLUSIONS: The occurrence of meningiomas is associated with ≥1 chromosomal deletions, and the absence of certain tumor suppressor genes may be the genetic basis for the familial growth of meningiomas.

10.
Ultrasound Med Biol ; 47(3): 517-526, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33277109

RESUMO

The purpose of this study was to explore the value of pre-operative prediction of lymphovascular invasion (LVI) in primary breast cancer patients undergoing modified radical mastectomy and to develop a nomogram based on multiparametric ultrasound and clinicopathologic indicators. All patients with primary breast cancer confirmed by pre-operative biopsy underwent B-mode ultrasound and contrast-enhanced ultrasound examinations. Post-operative pathology was used as the gold standard to identify LVI. Lasso regression was used to select predictors most related to LVI. A nomogram was developed to calculate the diagnostic efficacy. We bootstrapped the data for 500 times to perform internal verification, drawing a calibration curve to verify prediction ability. A total of 244 primary breast cancer patients were included. LVI was observed in 77 patients. Ten predictors associated with LVI were selected by Lasso regression. The area under the curve, sensitivity, specificity and accuracy for the nomogram were 0.918, 92.2%, 76.7% and 81.6%, respectively. And the nomogram calibration curve showed good consistency between the predicted probability and the actual probability. The nomogram developed could be used to predict LVI in primary breast cancer patients undergoing modified radical mastectomy and to help in clinical decision-making.

11.
Liver Int ; 41(2): 333-347, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33159371

RESUMO

BACKGROUND & AIMS: Patients with obstructive jaundice (OJ) are considered to be prothrombotic with increased risk of thromboembolism complications. The role of neutrophil extracellular traps (NETs) in procoagulant activity (PCA) and thrombosis risk in patients with OJ is unclear. In this study, we investigated NETs formation in OJ patients and the role of elevated unconjugated bilirubin (UCB) in inducing NETs, resulting in enhanced PCA and endothelial injury. METHODS: NETs of OJ patients and healthy controls were measured. NETs PCA was assessed via coagulation time (CT), fibrin formation and purified coagulation complex production assays. Visualization of NETs and mitochondrial reactive oxygen species (MitoROS) were performed with a fluorescence microscope. We further used confocal microscopy to quantify the exposure of phosphatidylserine (PS), fibrin strands and FVa/Xa on Human umbilical vein endothelial cells (HUVECs). RESULTS: Assessment of NETs components levels revealed greater NETs production in OJ patients than in healthy controls. Importantly, OJ-NETs were responsible for enhanced PCA. UCB induced NETs formation via MitoROS accumulation and mitochondrial mobilization. HUVECs cocultured with OJ NETs lost their cell-cell junctions and consequently converted to a procoagulant phenotype. The PCA was attenuated by using DNase I alone or in combination with lactadherin. CONCLUSIONS: Our results suggest that UCB-induced NETs play a prominent role in promoting the hypercoagulable and prothrombotic state in OJ patients. The increased MitoROS accumulation in neutrophils initiated NETosis. NETs are promising targets for indicating or improving coagulation disorders in OJ patients.

12.
J Dairy Sci ; 104(1): 47-60, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33162096

RESUMO

Infant formula is used as a supplement for newborns. Although bovine milk-based infant formulas dominate the market, caprine milk-based infant formula has attracted increasing attention because of its lower allergenicity. This study compared the digestive peptidome of bovine and caprine milk serum proteins by using in vitro infant simulating conditions. The result showed that the degradation pattern of milk proteins was similar, whereas the digestive rates of milk proteins differed between bovine and caprine milks. Several proteins, such as α-lactalbumin (LALBA), ß-lactoglobulin (LGB), serum amyloid A protein (SAA1), glycosylation-dependent cell adhesion molecule 1 (GLYCAM1), and lactotransferrin (LTF), released more peptides during digestion of caprine milk serum than during digestion of bovine milk serum; however, more peptides derived from αS1-casein (CSN1S1) were found in bovine digesta. In addition, antimicrobial-related peptides were mostly only found in caprine intestinal digesta. The results of this study may be useful in understanding the digestion characteristics of milk serum proteins and providing guidance on the improvement of infant formula.

13.
J Biomol Struct Dyn ; 39(1): 310-318, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31872783

RESUMO

Src homology 3 (SH3) domains are small protein modules involved in the regulation of important cellular pathways such as proliferation and migration, which canonically prefer to recognize and interact with proline-rich peptide ligands with class I or class II motif. Previously, we identified two self-binding peptides (SBPs) in human c-Src tyrosine kinase, of which the first SBP (fSBP) segment (248SKPQTQGLAK257) fulfills intramolecular interaction with the kinase SH3 domain to regulate the kinase function. The segment (and its equivalents in other c-Src family members) does not contain canonical class II motif (PxxQxL versus PxxPx+), but can bind to SH3 domain in a routine class II mode. Existing theories such as non-polyproline-II binding conformation, unusual peptide-binding pocket and extensive use of contacts cannot explain this atypical recognition phenomenon. Here, we performed a systematic investigation of SH3-fSBP binding in different conditions, including the segment in full-length kinase or in isolated state, the kinase in different forms and the fSBP residue mutations, by using microsecond molecular dynamics simulations, conformational clustering analyses and binding energetics calculations. We purposed a new mechanism that the protein context is primarily responsible for the atypical intramolecular SH3-fSBP recognition in c-Src kinase, which can promote the tight packing of segment against domain surface, support the segment polyproline-II (PPII) conformation in unbound state, and avoid unfavorable segment interactions with SH3 charged region by forming a C-terminal t-turn. In addition, the only proline residue Pro250 of fSBP segment is also required for the segment recognition by SH3 domain in c-Src kinase context; lack of Pro250 residue the segment exhibits considerable disorder and cannot maintain in PPII helical conformation, thus largely impairing the domain-segment binding capability. Further binding analysis confirms that the isolated fSBP peptide cannot bind effectively to SH3 domain out of kinase context, whereas its mutant version, i.e. fSBP(Q253P/L255R) peptide, which possesses the canonical class II motif, exhibits an increased affinity to the domain.Communicated by Ramaswamy H. Sarma.

14.
Phytochemistry ; 182: 112613, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33316595

RESUMO

Seven undescribed isopimarane diterpene glycosides hypoxylonoids A-G, along with five known analogues were obtained from the fungus Xylaria hypoxylon. The structures and absolute configurations of hypoxylonoids A-G were confirmed by extensive spectroscopic and single-crystal X-ray diffraction analyses. Among these compounds, the γ-lactone moiety formed between C-19 and C-6 of hypoxylonoid A; the 1,2-methyl shift of Me-18 of hypoxylonoids B and E; and the decarboxylation of C-19 of hypoxylonoid E, make them outstanding from the isopimarane family. Single crystal X-ray diffraction analyses of hypoxylonoids A, C, F, and 15-hydroxy-16-α-D-mannopyranosyloxyisopimar-7-en-19-oic acid was performed to determine their absolute structural configuration.

15.
Sci Total Environ ; 752: 141958, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32892054

RESUMO

Biochar addition can reduce methane (CH4) emissions from paddy soils while the mechanisms involved are not entirely clear. Here, we studied the effect of biochar addition on CH4 emissions, and the abundance and community composition of methanogens and methanotrophs over two rice cultivation seasons. The experiment had the following five treatments: control (CK), chemical fertilizer application only (BC0), and 0.5% (w/w) (BC1), 1% (BC2), and 2% of biochar applied with chemical fertilizers (BC3). The season-wide CH4 emissions were decreased (P < 0.05) by 22.2-95.7% in biochar application compared with BC0 in the two rice seasons (2017 and 2018). In 2017, biochar application decreased methanogenic archaea (mcrA) but increased methanotrophic bacteria (pmoA) abundances, and decreased the ratio of mcrA/pmoA, as compared with BC0 (P < 0.05). In 2018, the abundance of mcrA was lower in BC2 and BC3 than in BC0 (P < 0.05) but was not different between BC0 and BC1, and the abundance of pmoA was lower in BC1, BC2 and BC3 than in BC0 (P < 0.05). The CH4 emissions were positively related to abundances of the mcrA gene (P < 0.01) but not to that of the pmoA gene in two rice seasons. Rice grain yield was increased by 62.2-94.1% in biochar addition treatments compared with BC0 in the first year (P < 0.01) and by 29.9-37.6% in BC2 and BC3 compared with BC0 in the second year (P < 0.05). Biochar application decreased CH4 emissions by reducing methanogenic archaea abundance in the studied flooded paddy soil.


Assuntos
Oryza , Solo , Archaea/genética , Carvão Vegetal , Metano , Microbiologia do Solo
16.
Dev Comp Immunol ; 115: 103880, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33022353

RESUMO

IκB kinase α (IKKα) is a vital component of the IKK complex, which is involved in innate immune response, inflammation, cell death and proliferation. Although the functional characteristics of IKKα have been extensively studied in mammals and fish, the roles of IKKα in avian remain largely unknown. In this study, we cloned and characterized the duck IKKα (duIKKα) gene for the first time. DuIKKα encoded a protein of 757 amino acid residues and showed high sequence identities with the goose IKKα. The duIKKα was expressed in all tested tissues, and a relatively high expression of duIKKα mRNA was detected in liver and heart. Overexpression of duIKKα dramatically increased NF-κB activity and induced the expression of duck cytokines IFN-ß, IL-1ß, IL-6, IL-8 and RANTES in DEFs. Knockdown of duIKKα by small interfering RNA significantly decreased LPS-, poly(I:C)-, poly(dA:dT)-, duck enteritis virus (DEV)-, or duck Tembusu virus (DTMUV)-induced NF-κB activation. Moreover, duIKKα exhibited antiviral activity against DTMUV infection. These findings provide important insights into the roles of duIKKα in avian innate immunity.

17.
Dev Comp Immunol ; 115: 103906, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33127560

RESUMO

Duck Tembusu virus (DTMUV) is a newly emerging pathogenic flavivirus that caused severe egg drop syndrome in laying ducks in China since 2010, leading to massive economic losses to the duck industry. Although the DTMUV E protein is considered to be critical in inducing the protective immune response, the functional epitopes within this protein remain largely unknown. In the present study, we isolated a DTMUV neutralizing monoclonal antibody (mAb) 3B8 from DTMUV E-immunized mice. Epitope mapping showed that mAb 3B8 recognized a novel linear epitope FSCLGMQNR located on the extreme N-terminal of the domain I (EDI) of E protein. Sequence alignment and Western blot analyses showed that the epitope is greatly conserved with high DTMUV-specificity. Moreover, upon cloning the heavy and light chain variable region sequences of mAb 3B8, we prepared the single-chain variable antibody fragment (scFv) 3B8 by connecting the two chains via a flexible peptide linker. The recombinant scFv 3B8 exhibited antiviral activity against DTMUV infection in vitro and in vivo. Our results provide valuable implications for the development of DTMUV vaccines and therapeutics.

18.
J Environ Manage ; 277: 111325, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949949

RESUMO

Technological progress greatly contributes to the promotion of carbon productivity (CP). This study aims to identify an appropriate mode of technological progress that increases CP. A data envelopment analysis-based method was used to investigate the impacts of four forms of technological progress under two classifications of CP: the progress of neutral technology (NT) and capital-embodied technology (CET) under a technological source and the progress of energy technology (ET) and carbon technology (CT) under an abatement process. We applied dynamic panel data models to deeply analyze the different impacts of the four forms of technological progress on the CPs of Chinese manufacturing industries from 1995 to 2015. Results show that (1) a change in ET contributes more to the promotion of CP than a change in CT; (2) a change in CET promotes CP more than a change in NT; and (3) the indirect effect of a change in CET on CP through a change in ET and the indirect effect of a change in NT on CP through a change in CT are advantageous. These findings provide important policy implications in promoting technological progress and improving Chinese MIs' CPs. Significant policy measures based on theoretical and empirical conclusions are proposed.


Assuntos
Carbono , Tecnologia , Carbono/análise , Dióxido de Carbono/análise , China , Eficiência , Indústria Manufatureira
19.
J Ultrasound Med ; 40(1): 151-161, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32681744

RESUMO

OBJECTIVES: The aim of this study was to explore a modified model to simplify the diagnostic process for American College of Radiology Breast Imaging Reporting and Data System category 3 to 5 breast lesions and evaluate the model's diagnostic efficacy. METHODS: A retrospective review was conducted of breast lesions examined by B-mode ultrasound (US) and contrast-enhanced ultrasound (CEUS) and diagnosed by histopathologic examination from October 2016 to August 2019. The US characteristics of a combined model (US + CEUS model) with relatively high diagnostic value were selected by a lasso regression analysis to establish a modified model. Two nomograms were developed. The results were internally validated by bootstrap resampling. RESULTS: Overall, 206 breast lesions in 198 patients, 136 benign and 70 malignant, were included. Ultrasound characteristics included in the modified model were shape, margin, microcalcification, enhanced intensity, enhanced scope, and enhanced time. For the US + CEUS model and modified model, sensitivities were 94.3% and 93.3%; specificities were 85.9% and 81.4%; accuracies were 89.3% and 88.7% and areas under the curve were 0.957 and 0.944, respectively. No statistically significant differences were seen in the diagnostic efficacies of the models (P = .097). Bootstrap-corrected sensitivities, specificities. and accuracies of the models were consistent with these results. Bootstrap-corrected areas under the curve for the US + CEUS model and the modified model were 0.955 and 0.940, respectively. CONCLUSIONS: The modified model with fewer indicators conveniently and effectively diagnosed the malignancy of Breast Imaging Reporting and Data System category 3 to 5 breast lesions without reducing diagnostic efficacy.

20.
Chemosphere ; 263: 127950, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297019

RESUMO

In this study, the catalytic ability and mechanisms involved in activating peroxymonosulfate (PMS) with Mn3O4 and the degradation pathways of bisphenol-AF (BPAF) removal was investigated. SO4-• and ·OH which were explored by and scavenging tests were the major reactive radicals in the Mn3O4/PMS system. A simple simulation algorithm was also used to calculate the relative concentrations of SO4-• ([SO4-•]) and ·OH ([·OH]) which were 8.39 × 10 -15 M and 6.96 × 10 -13 M, respectively. The mechanism for the electron transfer between the Mn (II) and Mn (III) species was discussed. Three degradation pathways of BPAF were determined by the GC/MS and LC/MS technology, including chemical mechanism of oxidation, hydroxylation, electron transfer, polymerization, and ring-cleavage. In addition, the results suggested that the Mn3O4/PMS system had an efficient total organic carbon (TOC) removal rate and excellent environmental adaptability, the removal rate of TOC being as high as 73.2% in the control condition. Furthermore, the reuse experiments and the comparison on the structural and componential changes of Mn3O4 powder before and after reaction demonstrated that the Mn3O4 catalyst possessed excellent stability and reusability. Finally, a maximum BPAF degradation of approximately 90.0% was achieved on the optimal conditions for 500 mg/L Mn3O4 dosage, 4 mM PMS concentration, 7.0 ± 0.2 initial pH, and 5 mg/L BPAF concentration respectively. And the effect of the coexisting anions and natural environmental water quality were also considered. This study demonstrated the Mn3O4/PMS system can be considered as a green approach for the removal of environmental reluctant pollutants.


Assuntos
Óxidos , Peróxidos , Catálise , Oxirredução
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