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1.
RSC Adv ; 14(16): 11007-11016, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38586448

RESUMO

This study systematically investigates the mechanism of NOx emissions during the sintering process, with a focus on the utilization of biochar as an auxiliary fuel to replace a portion of the coke traditionally used in iron ore sintering. The research involved the simulation of sintering raw material ratios using iron ore, biochar, and coke powder. Substitution levels of biochar for coke were set at 0%, 20%, 40%, 50%, 60%, 80%, and 100%. NOx emissions during the sintering process were monitored using a sintering flue gas detection system. Simultaneously, a comprehensive analysis of the sintered ore was conducted with the aim of producing samples that meet sintered ore requirements while reducing NOx emissions. Experimental results revealed that when biomass charcoal substitution for coke reached 50%, the lowest NO emissions were observed during the sintering process, with a reduction of over 90% in accumulated NO emissions in the exhaust gas. In this process, due to the participation of biochar, CO2 emissions were reduced by approximately 50% compared to traditional sintering processes. The study also analyzed the physicochemical properties of the sintered ore using methods such as XRD, Raman, FTIR, and Vickers hardness testing. The results indicated that the hardness fluctuated within the range of 610 to 710N for sintered products with different levels of biochar substitution, and there were minimal changes in Fe element content and crystal phase transformations.

2.
Front Med (Lausanne) ; 10: 1138507, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324149

RESUMO

Background: Vaginal microecology has a definite influence on human papillomavirus (HPV) infection and clearance, but the specific correlation is still controversial. This research aimed to investigate the differences in the vaginal microenvironment of different types of HPV infection and also provide data supporting clinical diagnosis and treatment. Methods: According to strict inclusion and exclusion criteria, the case data of 2,358 female patients who underwent vaginal microecology and HPV-DNA tests at the same time in the Department of Obstetrics and Gynecology of the First Affiliated Hospital of Xi'an Jiaotong University from May 2021 to March 2022 were retrospectively analyzed. The population was divided into two groups: an HPV-positive group and an HPV-negative group. HPV-positive patients were further classified into HPV16/18-positive group and HPV other subtypes positive group. The vaginal microecology of HPV-infected patients was analyzed using the chi-square test, Fisher's exact test, and logistic regression. Results: Among the 2,358 female patients, the HPV infection rate was 20.27% (478/2,358), of which the HPV16/18 infection rate was 25.73% (123/478), and the HPV other subtypes infection rate was 74.27% (355/478). The difference in HPV infection rates between the age groups was statistically significant (P < 0.01). The prevalence of mixed vaginitis was 14.37% (339/2,358), with bacterial vaginosis (BV) paired with aerobic vaginitis (AV) accounting for the majority (66.37%). The difference in HPV infection rates among mixed vaginitis was not statistically significant (P > 0.05). The prevalence of single vaginitis was 24.22% (571/2,358), with the most frequent being vulvovaginal Candidiasis (VVC; 47.29%, 270/571), and there was a significant difference in HPV infection rates among single vaginitis (P < 0.001). Patients with BV had a higher risk of being positive for HPV16/18 (OR: 1.815, 95% CI: 1.050-3.139) and other subtypes (OR: 1.830, 95% CI: 1.254-2.669). Patients with Trichomoniasis were at higher odds of other HPV subtype infections (OR: 1.857, 95% CI: 1.004-3.437). On the contrary, patients with VVC had lower odds of becoming infected with other HPV subtypes (OR: 0.562, 95% CI: 0.380-0.831). Conclusion: There were disparities in HPV infection among different age groups; therefore, we should pay attention to the prevention and treatment of susceptible individuals. BV and Trichomoniasis are linked to HPV infection; hence, restoring the balance of vaginal microecology could assist in the prevention of HPV infection. As a protective factor for other HPV subtype infections, VVC may provide new insights into the development of immunotherapeutic therapies.

3.
J Int Med Res ; 50(7): 3000605221103546, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35796516

RESUMO

OBJECTIVE: To comprehensively evaluate the significance of circular RNAs (circRNAs) as potential diagnostic biomarkers for systemic lupus erythematosus (SLE) via pooled analyses of data from published studies that focussed on the association between circRNAs and SLE. METHODS: The systematic review and meta-analysis protocol was registered in PROSPERO (registration No. CRD42021229383). Relevant studies published before 3 April 2022 were selected to verify the relationship between circRNA expression levels and SLE. Extracted data were analysed using a random-effects model with Meta-DiSc 1.4 and Stata 16 software. Transcription factors related to hsa_circ_0000479 and its parental gene were extracted from the TRCirc and hTFtarget databases, respectively. RESULTS: A total of 10 studies, involving 438 patients with SLE and 434 controls, were included in the meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio of circRNAs in detecting SLE were 0.66 (95% confidence interval [CI] 0.63, 0.70), 0.79 (95% CI 0.76, 0.82), and 10.80 (95% CI 6.58, 17.73), respectively. The area under the summary receiver operating characteristic curve was 0.8366. CONCLUSIONS: Meta-analysis of pooled data indicated a moderate accuracy of circRNAs in diagnosing SLE. The exact diagnostic value of circRNAs and the mechanisms of interaction between circRNAs and their parental genes should be confirmed in further studies.


Assuntos
Lúpus Eritematoso Sistêmico , RNA Circular , Biomarcadores/metabolismo , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/genética , RNA Circular/genética , Curva ROC
4.
Front Plant Sci ; 13: 803472, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783922

RESUMO

Golden buckwheat (Fagopyrum cymosum) is used in Traditional Chinese Medicine. It has received attention because of the high value of its various medicinal and nutritional metabolites, especially flavonoids (catechin and epicatechin). However, the metabolites and their encoding genes in golden buckwheat have not yet been identified in the global landscape. This study performed transcriptomics and widely targeted metabolomics analyses for the first time on rhizomes of golden buckwheat. As a result, 10,191 differentially expressed genes (DEGs) and 297 differentially regulated metabolites (DRMs) were identified, among which the flavonoid biosynthesis pathway was enriched in both transcriptome and metabolome. The integration analyses of the transcriptome and the metabolome revealed a network related to catechin, in which four metabolites and 14 genes interacted with each other. Subsequently, an SG5 R2R3-MYB transcription factor, named FcMYB1, was identified as a transcriptional activator in catechin biosynthesis, as it was positively correlated to eight flavonoid biosynthesis genes in their expression patterns and was directly bound to the promoters of FcLAR2 and FcF3'H1 by yeast one hybrid analysis. Finally, a flavonoid biosynthesis pathway was proposed in the rhizomes of golden buckwheat, including 13 metabolites, 11 genes encoding 9 enzymes, and 1 MYB transcription factor. The expression of 12 DEGs were validated by qRT-PCR, resulting in a good agreement with the Pearson R ranging from 0.83 to 1. The study provided a comprehensive flavonoid biosynthesis and regulatory network of golden buckwheat.

5.
Front Plant Sci ; 13: 828454, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386677

RESUMO

Powdery mildew has a negative impact on wheat growth and restricts yield formation. Therefore, accurate monitoring of the disease is of great significance for the prevention and control of powdery mildew to protect world food security. The canopy spectral reflectance was obtained using a ground feature hyperspectrometer during the flowering and filling periods of wheat, and then the Savitzky-Golay method was used to smooth the measured spectral data, and as original reflectivity (OR). Firstly, the OR was spectrally transformed using the mean centralization (MC), multivariate scattering correction (MSC), and standard normal variate transform (SNV) methods. Secondly, the feature bands of above four transformed spectral data were extracted through a combination of the Competitive Adaptive Reweighted Sampling (CARS) and Successive Projections Algorithm (SPA) algorithms. Finally, partial least square regression (PLSR), support vector regression (SVR), and random forest regression (RFR) were used to construct an optimal monitoring model for wheat powdery mildew disease index (mean disease index, mDI). The results showed that after Pearson correlation, two-band optimization combinations and machine learning method modeling comparisons, the comprehensive performance of the MC spectrum data was the best, and it was a better method for pretreating disease spectrum data. The transformed spectral data combined with the CARS-SPA algorithm was able to extract the characteristic bands more effectively. The number of bands screened was more than the number of bands extracted by the OR data, and the band positions were more evenly distributed. In comparison of different machine learning modeling methods, the RFR model performed the best (coefficient of determination, R 2 = 0.741-0.852), while the SVR and PLSR models performed similarly (R 2 = 0.733-0.836). Taken together, the estimation accuracy of spectral data transformation using the MC method combined with the RFR model (MC-RFR) was the highest, the model R 2 was 0.849-0.852, and the root mean square error (RMSE) and the mean absolute error (MAE) ranged from 2.084 to 2.177 and 1.684 to 1.777, respectively. Compared with the OR combined with the RFR model (OR-RFR), the R 2 increased by 14.39%, and the R 2 of RMSE and MAE decreased by 23.9 and 27.87%. Also, the monitoring accuracy of flowering stage is better than that of grain filling stage, which is due to the relative stability of canopy structure in flowering stage. It can be seen that without changing the shape of the spectral curve, and that the use of MC to preprocess spectral data, the use of CARS and SPA algorithms to extract characteristic bands, and the use of RFR modeling methods to enhance the synergy between multiple variables, and the established model (MC-CARS-SPA-RFR) can better extract the covariant relationship between the canopy spectrum and the disease, thereby improving the monitoring accuracy of wheat powdery mildew. The research results of this study provide ideas and methods for realizing high-precision remote sensing monitoring of crop disease status.

6.
Materials (Basel) ; 14(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34832146

RESUMO

We reported the second- and third-order temporal interference of two non-degenerate pseudo-thermal sources in a nitrogen-vacancy center (NV-). The relationship between the indistinguishability of source and path alternatives is analyzed at low temperature. In this article, we demonstrate the switching between three-mode bunching and frequency beating effect controlled by the time offset and the frequency difference to realize optical demultiplexer. Our experimental results suggest the advanced technique achieves channel spacing and speed of the demultiplexer of about 96% and 17 ns, respectively. The proposed demultiplexer model will have potential applications in quantum computing and communication.

7.
Nanotechnology ; 32(10): 105402, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33242845

RESUMO

Transition metal oxides with high theoretical capacities are widely investigated as potential anodes for alkali-metal ion batteries. However, the intrinsic conductivity deficiency and large volume changes during cycles result in poor cycling stability and low rate capabilities. Graphene has been widely used to support metal oxide for enhanced performance, but the cycling life is limited by the aggregation/collapse of active materials on graphene surface. Herein, we significantly improve the battery performance of graphene-metal oxide composite via pore engineering and surface protection. In this architecture, the mesoporous NiFe2O4 is designed for fast ion diffusion and volume accommodation, and the outer graphene protection can further enhance the electrical conductivity and prevent the aggregation during cycle. Thus, as-prepared G@p-NiFe2O4@G composite for lithium storage delivers high capacity (1244 mA h g-1 after 300 cycles at 0.2 A g-1), excellent rate performance (563 mA h g-1 at 4 A g-1), and outstanding cycling life up to 1200 cycles at 1.5 A g-1. For sodium storage, it also displays good cycling stability and superior rate performance. Moreover, the effects of various microstructures on the battery performance, the reaction kinetics of various electrodes, and the reaction mechanism of NiFe2O4 have been systematically investigated in this work.

8.
J Int Med Res ; 48(9): 300060520961916, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32993424

RESUMO

Hepatic sinusoidal obstruction syndrome (HSOS) can be caused by the intake of pyrrolizidine alkaloids (PAs). The disease has a high mortality rate, a poor prognosis and limited treatment options. Managing pyrrolizidine alkaloid-induced hepatic sinusoidal obstruction syndrome (PA-HSOS) is a significant challenge for hepatologists. This case report describes five patients with PA-HSOS that were treated with low molecular weight heparin (LMWH) between 2014 and 2019. All five patients had a history of taking PA-containing herbal preparations before the onset of the disease. They all met the Nanjing diagnostic criteria and were diagnosed with PA-HSOS. Symptomatic treatment was administered to all five patients. In addition to symptomatic treatment, all five patients were treated with LMWH for approximately 8-21 days. After treatment, their ascites disappeared, symptoms improved and the hepatic venous blood flow had improved compared with before treatment. There was no obvious discomfort during the 6 months of follow-up. LMWH may play a useful role in the early treatment of PA-HSOS. Therefore, for patients in the early stages of PA-HSOS, in addition to symptomatic treatment, early anticoagulant intervention can be attempted to improve patient prognosis under close monitoring of coagulation.


Assuntos
Hepatopatia Veno-Oclusiva , Alcaloides de Pirrolizidina , Heparina de Baixo Peso Molecular/uso terapêutico , Hepatopatia Veno-Oclusiva/induzido quimicamente , Hepatopatia Veno-Oclusiva/tratamento farmacológico , Humanos , Prognóstico
9.
Medicine (Baltimore) ; 99(22): e20502, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32481469

RESUMO

The aim of the study was to develop a new early noninvasive diagnostic model for primary biliary cholangitis (PBC).A total of 118 PBC patients who had undergone a liver biopsy were enrolled in the study, and were randomized into a model group (78 patients) and a validation group (40 patients). The patients' histological stages were based on the classifications of the Scheuer's stage. All common parameters and liver pathological results were analyzed. And total bile acid to platelet ratio, aspartate aminotransferase to platelet ratio index, fibrosis index based on 4 factors and red cell distribution width to platelet ratio were calculated.There were 106 (89.8%) women and 12 men in this study, and the number of patients in Scheuer stage I, II, III, and IV hepatic fibrosis was 52 (44.1%), 36 (30.5%), 26 (22.0%), and 4 (3.4%), respectively. The areas under the receiver operating characteristic curves of the total bile acid to platelet ratio (TPR), the aspartate aminotransferase to platelet ratio index, the fibrosis index based on 4 factors , and the red cell distribution width to platelet ratio for predicting advanced liver fibrosis were 0.771, 0.715, 0.618, and 0.517 respectively. The areas under the receiver operating characteristic curves of the TPR was higher than other non-invasive serological models.As a simple, inexpensive and easily accessible non-invasive liver fibrosis diagnostic model, the TPR may be a new noninvasive marker for predicting histologic severity of PBC.


Assuntos
Bile/metabolismo , Colangite/complicações , Cirrose Hepática Biliar/etiologia , Contagem de Plaquetas , Aspartato Aminotransferases/metabolismo , Biomarcadores/análise , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
10.
Food Sci Nutr ; 7(8): 2702-2707, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31428357

RESUMO

Curcumin possesses antioxidant, anti-inflammatory, and other properties. However, this compound exhibits low bioavailability because of its poor solubility and stability. In this paper, lysozyme nanoparticles were fabricated through solvent evaporation, and then, the solubilization and protection capability of curcumin were investigated. Lysozyme nanoparticles were characterized by dynamic light scattering technique, atomic force microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. The load capacity and stability in thermal environment were further explored. Results showed that the lysozyme nanoparticle displayed a spherical structure (127.9 ± 2.12 nm) with favorable distribution. The solubility of curcumin can increase to 22 µg/mL. After encapsulation by lysozyme nanoparticles, the retentive curcumin can reach up to 67.9% and 30.25% at 25°C and 50°C, respectively, significantly higher than that of free curcumin. Meanwhile, experiments on DPPH free radicals indicated the curcumin loaded by lysozyme nanoparticle possessed higher free radical scavenging activity than that of free curcumin with same treatments. The results confirmed that lysozyme nanoparticles exhibit potential applications in solubilizing and protecting the environment-sensitive hydrophobic functional components.

11.
Cell Rep ; 27(2): 455-466.e5, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970249

RESUMO

Induced pluripotent stem cells (iPSCs) are a promising melanocyte source as they propagate indefinitely and can be established from patients. However, the in vivo functions of human iPSC-derived melanocytes (hiMels) remain unknown. Here, we generated hiMels from vitiligo patients using a three-dimensional system with enhanced differentiation efficiency, which showed characteristics of human epidermal melanocytes with high sequence similarity and involved in multiple vitiligo-associated signaling pathways. A modified hair follicle reconstitution assay in vivo showed that MITF+PAX3+TYRP1+ hiMels were localized in the mouse hair bulb and epidermis and produced melanin up to 7 weeks after transplantation, whereas MITF+PAX3+TYRP1- hiMelanocyte stem cells integrated into the bulge-subbulge regions. Overall, these data demonstrate the long-term functions of hiMels in vivo to reconstitute pigmented hair follicles and to integrate into normal regions for both mature melanocytes and melanocyte stem cells, providing an alternative source of personalized cellular therapy for depigmentation.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/transplante , Melanócitos/metabolismo , Transplante de Células-Tronco/métodos , Animais , Humanos , Camundongos , Coelhos , Transplante Autólogo
12.
Angew Chem Int Ed Engl ; 58(18): 6042-6047, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30860633

RESUMO

Cobalt spinel oxides are a class of promising transition metal (TM) oxides for catalyzing oxygen evolution reaction (OER). Their catalytic activity depends on the electronic structure. In a spinel oxide lattice, each oxygen anion is shared amongst its four nearest transition metal cations, of which one is located within the tetrahedral interstices and the remaining three cations are in the octahedral interstices. This work uncovered the influence of oxygen anion charge distribution on the electronic structure of the redox-active building block Co-O. The charge of oxygen anion tends to shift toward the octahedral-occupied Co instead of tetrahedral-occupied Co, which hence produces strong orbital interaction between octahedral Co and O. Thus, the OER activity can be promoted by pushing more Co into the octahedral site or shifting the oxygen charge towards the redox-active metal center in CoO6 octahedra.

13.
Nanomicro Lett ; 11(1): 24, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34137956

RESUMO

Currently, electromagnetic (EM) pollution poses severe complication toward the operation of electronic devices and biological systems. To this end, it is pertinent to develop novel microwave absorbers through compositional and structural design. Porous carbon (PC) materials demonstrate great potential in EM wave absorption due to their ultralow density, large surface area, and excellent dielectric loss ability. However, the large-scale production of PC materials through low-cost and simple synthetic route is a challenge. Deriving PC materials through biomass sources is a sustainable, ubiquitous, and low-cost method, which comes with many desired features, such as hierarchical texture, periodic pattern, and some unique nanoarchitecture. Using the bio-inspired microstructure to manufacture PC materials in mild condition is desirable. In this review, we summarize the EM wave absorption application of biomass-derived PC materials from optimizing structure and designing composition. The corresponding synthetic mechanisms and development prospects are discussed as well. The perspective in this field is given at the end of the article.

14.
Small ; 14(16): e1703338, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29356378

RESUMO

Development of efficient, affordable, and sustainable energy storage technologies has become an area of interest due to the worsening environmental issues and rising technological dependence on Li-ion batteries. Na-ion batteries (NIBs) have been receiving intensive research efforts during the last few years. Owing to their potentially low cost and relatively high energy density, NIBs are promising energy storage devices, especially for stationary applications. A fundamental understanding of electrode properties during electrochemical reactions is important for the development of low cost, high-energy density, and long shelf life NIBs. This Review aims to summarize and discuss reaction mechanisms of the major types of NIB electrode materials reported. By appreciating how the material works and the fundamental flaws it possesses, it is hoped that this Review will assist readers in coming up with innovative solutions for designing better materials for NIBs.

15.
Langmuir ; 33(1): 311-321, 2017 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-27990822

RESUMO

To investigate the influence of halogen bond (XB) on the gelation of a one-component organogel system, a new family of 5-iodo-1H-1,2,3-triazole and 1H-1,2,3-triazole gelators was designed and synthesized. The iodo gelators (1I, 3I) gelled various solvents at low concentrations and formed many superorganogels, whereas the hydrogenous gelators (1H, 3H) showed much poorer gelling performance. An X-ray analysis of the single crystals of two reference compounds (16I, 16H) reveals that the unusual C-I···O XB interaction is responsible for this difference. The results of spectroscopic examinations (XRD, SEM, 1H NMR, and UV) are well consistent with those of single-crystal analyses. Under the guidance of the XB interaction and the weak π-π interaction, 1I and 3I self-assemble to hexagonal columnar aggregations in the gel state, whereas 1H and 3H, driven by CH-π interactions, feature the formation of gels with a lamellar structure. The mechanical property of iodo gels is much better than that of hydrogenous gels under the same concentration. Gels from 1I respond to the stimuli of Hg2+, Cu2+, Zn2+, and Mg2+ as perchlorate salts, and gels from 1H are selectively responsive to Hg2+ solely.

16.
Adv Mater ; 29(6)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27918130

RESUMO

Laser pyrolyzed SnO2 nanoparticles with an option of nitrogen (N) doping are prepared using a cost-effective method. The electrochemical performance of N-doped samples is tested for the first time in Li-ion batteries where the sample with 3% of N-dopant exhibits optimum performance with a capacity of 522 mAh gactive material-1 that can be obtained at 10 A g-1 (6.7C).

17.
Adv Sci (Weinh) ; 2(6): 1500097, 2015 06.
Artigo em Inglês | MEDLINE | ID: mdl-27708996

RESUMO

Reserving interior void space in the cable-like structure of multiwalled carbon nanotubes-in-SnO2-in-carbon layer (MWNTs@SnO2@C) is reported for the first time. Such a design enables the structure performing excellent for Li and Na storage, which benefit from the good electrical conductivity of MWNTs and carbon layer as well as the reserved void space to accommodate the volume changes of SnO2.

18.
J Environ Sci (China) ; 25 Suppl 1: S89-92, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25078848

RESUMO

In acidic solution, thiocyanate molecules reacted with ferric ions to produce red complexes. The concentration of thiocyanate could be determined by spectrophotometer. The effects of wavelength, volume of color reagent, acidity and color time on absorbance were investigated. The interferences of co-existing ion were discussed as well. Results showed that the relation between absorbance and the concentration of thiocyanate was in accord with Beer's law when the concentration of thiocyanate was 2-20 mg/L. The linear regression equation was Absorbance = 0.0523Concentration-0.0156, with a linear correlation coefficient of 0.9997. The average recovery rates of two kinds of vacuum carbonate desulfurization wastewater were 100.95% and 99.62%, and relative standard deviations were 0.79% and 0.14% respectively. It shows that the method was quick, high precision, accurate and easy to handle.


Assuntos
Vácuo , Absorção Fisico-Química , Ácidos/química , Carbonatos/química , Cor , Compostos Férricos/análise , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Íons , Nitratos/análise , Padrões de Referência , Enxofre/química , Tiocianatos/análise , Fatores de Tempo , Águas Residuárias/química
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