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1.
Biochem Biophys Res Commun ; 709: 149820, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38547605

ABSTRACT

While the relationship between single receptor lymphocytes and cancer has been deeply researched, the origin and biological roles of dual receptor lymphocytes in tumor microenvironment (TME) remain largely unknown. And since nasopharyngeal carcinoma (NPC) is a type of cancer closely associated with immune infiltration, studying the TME of NPC holds particular significance. Utilizing single-cell RNA sequencing combined with T cell receptor (TCR) and B cell receptor (BCR) sequencing (scRNA + TCR + BCR-seq), we analyzed data from 7 patients with NPC and 3 patients with nasopharyngeal lymphatic hyperplasia (NLH). In our research, it was firstly found that the presence of dual receptor lymphocytes in both the TME of NPC and the inflammatory environment of NLH. We also confirmed their clonal expansion, suggesting their potential involvement in the immune response. Subsequently, we further discovered the lineage and the pairing characteristics. It was found that the dual receptor lymphocytes in NPC and NLH mainly originate from memory cells, and the predominant pairing type for dual TCR was ß+α1+α2 and dual BCR was heavy+κ+λ. By further analyzing their gene expression, we compared the function of dual receptor cells with single receptor cells in the context of both NPC and NLH. This groundbreaking research has enhanced our comprehension of the features of dual-receptor cells and has contributed to a better understanding of the TME in NPC. By comparing with NLH, it illuminates part of the alterations in the process of malignant transformation in NPC. These findings present the potential to acquire improved diagnostic markers and treatment modalities.


Subject(s)
Nasopharyngeal Neoplasms , Humans , Nasopharyngeal Carcinoma/pathology , Nasopharyngeal Neoplasms/genetics , Hyperplasia/pathology , Receptors, Antigen, T-Cell/genetics , B-Lymphocytes , Receptors, Antigen, B-Cell/genetics , Carrier Proteins/genetics , Tumor Microenvironment/genetics , Gene Expression , Single-Cell Analysis
2.
Inflammopharmacology ; 32(1): 873-883, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38227094

ABSTRACT

Lignan-rich beans, nuts, and various seeds are the main foods with antioxidative and hormone-modulating activities. Although the role of lignans in mediating hormone-dependent cancers and cardiovascular diseases is well characterized, the function of lignans in anti-arthritic activity and its underlying mechanisms remain unknown. Three new lignan derivatives, (-)-nortrachelogenin, trachelogenin, and matairesinol, were extracted from Loranthus parasiticus. After establishing the collagen-induced arthritis (CIA) model by intradermal injection of collagen, rats were treated with three new lignan derivatives ((-)-nortrachelogenin: 37%; trachelogenin: 27%; matairesinol: 25.7%) at a concentration of 50 mg/kg and 100 mg/kg, or methotrexate at 0.3 mg/kg. Mixed lignan derivatives significantly attenuated the immune responses in the joints of CIA rats, leading to lower levels of proinflammatory cytokines (IL-6 and TNF-α) and higher levels of free androgen in the serum compared to the CIA model. The results of molecular docking using AutoDock Vina showed that the lignan derivative (-)-nortrachelogenin was the most effective compound for binding to sex hormone-binding globulin (SHBG), thus inhibiting the activity of NFκB in LPS-stimulated macrophages. In this study, (-)-nortrachelogenin was identified as a novel natural lignan derivative with previously unrecognized anti-inflammatory activity. Its molecular mechanism appears related to the regulation of the NFκB/SHBG pathway. Our findings suggest that further application of sex hormone-like compounds in the treatment of rheumatoid arthritis and the potential clinical applications of (-)-nortrachelogenin are promising.


Subject(s)
4-Butyrolactone/analogs & derivatives , Arthritis, Experimental , Furans , Lignans , Rats , Animals , Arthritis, Experimental/chemically induced , Arthritis, Experimental/drug therapy , Arthritis, Experimental/metabolism , Sex Hormone-Binding Globulin , Molecular Docking Simulation , Lignans/pharmacology , Lignans/therapeutic use , Hormones/adverse effects
3.
Langmuir ; 39(34): 12153-12158, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37582402

ABSTRACT

The monomer emission property of the tetraphenylethene (TPE) derivative is rarely reported, and its photoluminescence (PL) mechanism related to supramolecular self-assembly needs further in-depth research. Two long alkyl chain modified derivatives, the TPE derivative (TPE-C10) and pyrene derivative (Pyrene-C10), are designed and synthesized, which possess similar supramolecular assembly behavior but exhibit different PL properties. TPE-C10 not only forms self-assembly morphologies with monomer emission but also emits aggregation-induced emission (AIE). Moreover, the polymer microspheres containing TPE-C10 and Pyrene-C10 are prepared, which can dissolve or swell in different organic solvents. The changed binding effect of polymer chains achieves the luminescence transformation of TPE-C10 from AIE to monomer emission. This work hopefully can enrich luminescent materials based on the monomer emission of the TPE derivative and provide a new method for mechanism studies about supramolecular self-assembly and luminescence.

4.
Sensors (Basel) ; 23(13)2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37447844

ABSTRACT

This paper investigates threshold-constrained joint waveform optimization for an integrated sensing and communication (ISAC) system. Unlike existing studies, we employ mutual information (MI) and sum rate (SR) as sensing and communication metrics, respectively, and optimize the waveform under constraints to both metrics simultaneously. This provides significant flexibility in meeting system performance. We formulate three different optimization problems that constrain the radar performance only, the communication performance only, and the ISAC performance, respectively. New techniques are developed to solve the original problems, which are NP-hard and cannot be directly solved by conventional semi-definite programming (SDP) techniques. Novel gradient descent methods are developed to solve the first two problems. For the third non-convex optimization problem, we transform it into a convex problem and solve it via convex toolboxes. We also disclose the connections between three optimizations using numerical results. Finally, simulation results are provided and validate the proposed optimization solutions.


Subject(s)
Algorithms , Computer Simulation
5.
Sensors (Basel) ; 18(2)2018 Feb 10.
Article in English | MEDLINE | ID: mdl-29439442

ABSTRACT

In the post-Cloud era, the proliferation of Internet of Things (IoT) has pushed the horizon of Edge computing, which is a new computing paradigm with data are processed at the edge of the network. As the important systems of Edge computing, wireless sensor and actuator networks (WSANs) play an important role in collecting and processing the sensing data from the surrounding environment as well as taking actions on the events happening in the environment. In WSANs, in-network data storage and information discovery schemes with high energy efficiency, high load balance and low latency are needed because of the limited resources of the sensor nodes and the real-time requirement of some specific applications, such as putting out a big fire in a forest. In this article, the existing schemes of WSANs on data storage and information discovery are surveyed with detailed analysis on their advancements and shortcomings, and possible solutions are proposed on how to achieve high efficiency, good load balance, and perfect real-time performances at the same time, hoping that it can provide a good reference for the future research of the WSANs-based Edge computing systems.

6.
Phytother Res ; 30(10): 1672-1679, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27373691

ABSTRACT

In Chinese traditional medicine, the rhizome of Atractylodes lancea (Thunb.) DC. (A. lancea) is used extensively for the treatment of several diseases such as rheumatic diseases, but its actions on rheumatoid arthritis have not been clarified. The purpose of this article was to investigate the pharmacological effect of an A. lancea rhizome extract on collagen-induced arthritis (CIA) in rats. The CIA model was induced by the injection of bovine type II collagen. The rats were orally administered the petroleum ether (PE) fraction of the A. lancea rhizome (0.82 and 1.64 mg/kg), methotrexate (0.3 mg/kg body weight), or a vehicle from day 7 to day 15 after the model was established. The histological examination and radiological observation showed that the PE fraction significantly reduced the inflammatory responses and collagen loss in the joints of the rats with CIA. The PE fraction inhibited the production of tumor necrosis factor-α, interleukin (IL)-1ß, IL-17, and IL-6 in the sera. Moreover, the treatment with the PE fraction in vivo was able to reduce the level of Beclin 1 protein in the synovial tissue of the rats. These results highlight the antiarthritic potential of the PE fraction of the A. lancea rhizome and provide further evidence of the involvement of Beclin 1 inhibition in the effects of the PE fraction of the A. lancea rhizome. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Arthritis, Experimental/drug therapy , Arthritis, Rheumatoid/drug therapy , Atractylodes/chemistry , Drugs, Chinese Herbal/chemistry , Petroleum/analysis , Animals , Arthritis, Experimental/pathology , Arthritis, Rheumatoid/pathology , Male , Rats , Rats, Wistar
7.
Int J Mol Sci ; 15(9): 17188-203, 2014 Sep 25.
Article in English | MEDLINE | ID: mdl-25257535

ABSTRACT

Spleen tyrosine kinase (Syk) plays an indispensable role through preliminary extracellular antigen-induced crosslinking of Fc receptor (FcR) in the pathogenesis of autoimmune disorders, such as rheumatoid arthritis. In this study, we identify Vam3, a dimeric derivative of resveratrol isolated from grapes, as an ATP-competitive inhibitor of Syk with an IC50 of 62.95 nM in an in vitro kinase assay. Moreover, docking and molecular dynamics simulation approaches were performed to get more detailed information about the binding mode of Vam3 and Syk. The results show that 11b-OH on ring-C and 4b-OH on ring-D could form two hydrogen bonds with Glu449 and Phe382 of Syk, respectively. In addition, arene-cation interaction between ring-D of Vam3 and Lys402 of Syk was also observed. These results indicate that ring-C and D play an essential role in Vam3-Syk interaction. Our studies may be helpful in the structural optimization of Vam3, and also aid the design of novel Syk inhibitors in the future.


Subject(s)
Benzofurans/pharmacology , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Protein-Tyrosine Kinases/antagonists & inhibitors , Stilbenes/chemistry , Stilbenes/pharmacology , Adenosine Triphosphate/metabolism , Benzofurans/chemistry , Crystallography, X-Ray , Dimerization , Humans , Hydrogen Bonding , Inhibitory Concentration 50 , Models, Molecular , Molecular Conformation , Molecular Docking Simulation , Molecular Dynamics Simulation , Molecular Structure , Protein Binding , Protein Conformation , Protein Kinase Inhibitors/chemistry , Resveratrol , Structure-Activity Relationship , Syk Kinase , Vitis/chemistry
8.
Glob Public Health ; 19(1): 2320422, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38416941

ABSTRACT

Media reporting greatly influences the civilians' mentality, which further exacerbates or mitigates outbreaks of infectious diseases, prolongs or shortens the pandemic process. Adopting corpus linguistic methods and Discursive news values analysis (DNVA) framework, this study examined the news values through key words, naming strategies and photographs in monkeypox-themed news reporting in Spanish and the US media, to analyse how they constructed the monkeypox pandemic in their news reporting, sold it to the public and exacerbated the pandemic in the two societies. The results show that the Spanish media constructed the monkeypox pandemic predominantly as an international medical event, distancing the monkeypox pandemic from the Spanish indigenous context and depriving the domestic audiences from the sense of urgency to take prevention actions. On the other hand, the US media mainly packaged the monkeypox pandemic as a political event which isolated this public health crisis from the life of the common people and hindered the US citizens' understanding of the requisite medical information about the monkeypox virus. It is concluded that the lack of indigenous focus of the Spanish media, and the excessively politicised focus of the US media are important factors that lead to the exacerbation of the monkeypox epidemic.


Subject(s)
Mass Media , Mpox (monkeypox) , Humans , Pandemics , Spain/epidemiology , Disease Outbreaks
9.
Article in English | MEDLINE | ID: mdl-38243957

ABSTRACT

BACKGROUND: Esophageal cancer (EC) is one of the deadliest malignancies worldwide. Gynostemma pentaphyllum Thunb. Makino (GpM) has been used in traditional Chinese medicine as a treatment for tumors and hyperlipidemia. Nevertheless, the active components and underlying mechanisms of anti-EC effects of GpM remain elusive. OBJECTIVE: This study aims to determine the major active ingredients of GpM in the treatment of EC and to explore their molecular mechanisms by using network pharmacology, molecular docking, and in vitro experiments. METHODS: Firstly, active ingredients and potential targets of GpM, as well as targets of EC, were screened in relevant databases to construct a compound-target network and a protein-protein interaction (PPI) network that narrowed down the pool of ingredients and targets. This was followed by gene ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Next, molecular docking, ADME and toxicity risk prediction, cell viability assays, in vitro scratch assays, Transwell cell invasion assays, and Western blotting analysis were subsequently applied to validate the results of the network analysis. RESULTS: The screening produced a total of 21 active ingredients and 167 ingredient-related targets for GpM, along with 2653 targets for EC. The PPI network analysis highlighted three targets of interest, namely AKT1, TP53, and VEGFA, and the compound-target network identified three possible active ingredients: quercetin, rhamnazin, and isofucosterol. GO and EKGG indicated that the mechanism of action might be related to the PI3K/AKT signaling pathway as well as the regulation of cell motility and cell migration. Molecular docking and pharmacokinetic analyses suggest that quercetin and isoprostanoid sterols may have therapeutic value and safety for EC. The in vitro experiments confirmed that GpM can inhibit EC cell proliferation, migration, and invasion and suppress PI3K and AKT phosphorylation. CONCLUSION: Our findings indicate that GpM exerts its anti-tumor effect on EC by inhibiting EC cell migration and invasion via downregulation of the PI3K/AKT signaling pathway. Hence, we have reason to believe that GpM could be a promising candidate for the treatment of EC.

10.
Glob Public Health ; 18(1): 2201315, 2023 Jan.
Article in English | MEDLINE | ID: mdl-38081776

ABSTRACT

This article compares the discursive construction of news values in English news reporting of China Daily and CNN about the COVID-19 vaccine, to reveal how the two media packaged the vaccine and improved the acceptance of the international community towards the vaccines made in the respective countries. Adopting corpus linguistic methods and Discursive news values analysis (DNVA) framework, this study examines news values through keywords, nomination strategies, and photographs. The results show that the two media outlets constructed the news value of Eliteness dominantly through a systematic combination of words and images, albeit in different ways. China Daily prominently consists of references to China's international communications in the production and application of the COVID-19 vaccine, at the same time packaging the COVID-19 vaccine as foreign aid to enhance diplomatic relations as well as protect and promote the order of the international community. In contrast, CNN chiefly demonstrates references to domestic medical experts and the well-known manufacturers of the COVID-19 vaccine, packaging the COVID-19 vaccine as the US' medical/commercial product. The respective ways in which they portray the COVID-19 vaccine have helped to bolster the acceptance of each country's vaccine by the international community.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , COVID-19/epidemiology , COVID-19/prevention & control , Mass Media , Communication , China
11.
Artif Intell Med ; 141: 102558, 2023 07.
Article in English | MEDLINE | ID: mdl-37295901

ABSTRACT

Traditional Chinese medicine (TCM) has gradually played an indispensable role in people's health maintenance, especially in the treatment of chronic diseases. However, there is always uncertainty and hesitation in the judgment and understanding of diseases by doctors, which affects the status recognition and optimal diagnosis and treatment decision-making of patients. In order to overcome the above problems, we lead into probabilistic double hierarchy linguistic term set (PDHLTS) to accurately describe language information in traditional Chinese medicine and make decisions. In this paper, a multi-criteria group decision making (MCGDM) model is constructed based on the MSM-MCBAC (Maclaurin symmetric mean-MultiCriteria Border Approximation area Comparison) method in the PDHL environment. Firstly, a PDHL weighted Maclaurin symmetric mean (PDHLWMSM) operator is proposed to aggregate the evaluation matrices of multiple experts. Then, combined with the BWM and maximizing deviation method, a comprehensive weight determination method is put forward to calculate the weights of criteria. Furthermore, we propose PDHL MSM-MCBAC method based on the Multi-Attributive Border Approximation area Comparison (MABAC) method and the PDHLWMSM operator. Finally, an example of a selection of TCM prescriptions is used and some comparative analyses are made to verify the effectiveness and superiority of this paper.


Subject(s)
Fuzzy Logic , Medicine, Chinese Traditional , Humans , Decision Making , Linguistics , Uncertainty
12.
Sci Rep ; 13(1): 21110, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-38036717

ABSTRACT

Sharp steering-braking at a high speed exposes sport utility vehicles with high gravity centers and narrow wheel tracks to the risks of tire locking, sideslip and rollover. To avoid these risks and ensure braking safety, yaw stability and roll stability upon steering-braking, a braking-yaw-roll stability integrated control strategy was proposed, which consists of a supervisor, an upper and a lower controller for the front and rear axle independent drive electric vehicle. In the supervisor, a nonlinear vehicle predictive model was constructed and four control modes were proposed according to the vehicle status and rollover indexes. The weight coefficients between braking force, yaw stability and roll stability are determined dynamically by the control mode and output to the upper controller. The upper controller used a nonlinear model predictive control to determine the longitudinal braking force distribution of the four wheels. And in the lower controller, the regenerative braking torque and friction braking torque of each wheel were distributed. Finally, simulation verifications were carried out on the high and low adhesion roads. The results show that the control strategy proposed in this study can effectively prevent the vehicle from rollover while ensuring braking safety and yaw stability.

13.
Ann Hum Genet ; 76(1): 25-32, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22175540

ABSTRACT

Published data on the association between the methylenetetrahydrofolate reductase (MTHFR) gene A1298C (rs1801131) polymorphism and male infertility risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. In this meta-analysis, a total of seven case-control studies including 1633 cases and 1735 controls were selected to evaluate the possible association. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the additive model, dominant model, recessive model, and allele-frequency genetic model. In the overall analysis, the frequency of the C1298 allele (C vs. A) was significantly associated with susceptibility to male infertility (OR = 1.12, 95% CI = 1.00-1.26). A subgroup analysis of the subjects showed that MTHFR 1298C was associated with significant increased risk of azoospermia in homozygote comparison (CC vs. AA) and recessive mode (CC vs. AA/AC) (OR = 1.66 for CC vs. AA genotype; OR = 1.67 for CC vs. AA/AC genotype). However, no statistically significant increased risk of oligoasthenoteratozoospermia was found in any of the genetic models. In conclusion, this meta-analysis supports that the MTHFR A1298C polymorphism is capable of causing male infertility susceptibility, especially azoospermia.


Subject(s)
Infertility, Male/genetics , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Polymorphism, Genetic , Azoospermia/genetics , Case-Control Studies , Humans , Male
14.
J Air Waste Manag Assoc ; 62(4): 485-8, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22616290

ABSTRACT

IMPLICATIONS: During the production of penicillin, a mass of waste bacterial residue is generated. In the past, the bacterial residues have been used for food additives. Unfortunately, doubts of their suitability as a feedstock have been raised because of the small amount of antibiotics and the degradation products remaining in the bacterial residues. So, penicillin bacterial residue is one of the hazardous wastes. Therefore, penicillin bacterial residue should be managed in accordance with the hazardous waste. To get a right method, the penicillin bacterial residue was characterized.


Subject(s)
Bacteria/metabolism , Hazardous Waste , Industrial Waste , Penicillins/metabolism , Refuse Disposal , Drug Industry , Environmental Pollution/prevention & control , Hot Temperature , Metals, Heavy/chemistry , Waste Management/methods
15.
Yao Xue Xue Bao ; 47(6): 689-95, 2012 Jun.
Article in Zh | MEDLINE | ID: mdl-22919714

ABSTRACT

Currently, about 300 million people worldwide are affected by asthma. Most of these sufferers inhale immunosuppressants (ie corticosteroids) and beta-adrenergic receptor agonists for their asthma treatment. However, about 5%-10% of patients of asthma have poor response to such treatment. Investigation of kinase signaling pathway and nuclear transcription factor as a target molecule in the treatment of allergic asthma has been the concern of scholars home and abroad. This paper reviewed inhibitors of kinase signaling pathway and nuclear transcription factors for the treatment of asthma.


Subject(s)
Asthma/enzymology , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Phosphoinositide-3 Kinase Inhibitors , Protein Kinase Inhibitors/therapeutic use , Protein-Tyrosine Kinases/antagonists & inhibitors , Transcription Factors/antagonists & inhibitors , Animals , Asthma/drug therapy , Humans , Protein-Tyrosine Kinases/metabolism , Signal Transduction
16.
Front Public Health ; 10: 1012374, 2022.
Article in English | MEDLINE | ID: mdl-36388262

ABSTRACT

During the COVID-19 pandemic, Chinese media played a significant role in dispelling the public panic, establishing the public confidence and stabilizing the society during the COVID-19 pandemic. This corpus-based discourse study explored the discursive construction of news values by Chinese media to reveal how the COVID-19 pandemic was packaged and sold to the public to establish confidence in the news reporting. Adopting corpus linguistic method and the Discursive news values analysis (DNVA) framework, this study examines news values through key words, news quotations, and images in the Chinese domestic mainstream media (http://www.people.com.cn/) during two different phases of the pandemic. The results show that during the first pandemic phase (2019.12.27-2020.4.28) when there had been no treatment protocol or understanding of the medical ramifications, Chinese media dominantly constructed political Eliteness through multimodal resources to portray a people-oriented government, a transparent notification mechanism and an immediate response capability to crises, and to give the public psychological support and to cultivate positive attitudes toward the government's policy. This news reporting way exposes the universal trust of Chinese society in the political authorities. During the second phase (2020.4.29-2020.8.31) when the cognition about the COVID-19 virus had been greatly improved and more medical treatment and prevention methods had been developed, the political Eliteness was replaced by medical Eliteness which was more vital to people's safety during the health crisis. We propose actionable recommendations for scholars to use this in-depth DNVA framework to examine the social trend of thoughts during major public health crisis.


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , Pandemics , Public Health , Trust , China/epidemiology
17.
ESC Heart Fail ; 8(6): 5392-5402, 2021 12.
Article in English | MEDLINE | ID: mdl-34657379

ABSTRACT

AIMS: Sleep apnoea and congestive heart failure (CHF) commonly co-exist, but their interaction is unclear. Metabolomics may clarify their interaction and relationships to outcome. METHODS AND RESULTS: We assayed 372 circulating metabolites and lipids in 1919 and 1524 participants of the Framingham Heart Study (FHS) (mean age 54 ± 10 years, 53% women) and Women's Health Initiative (WHI) (mean age 67 ± 7 years), respectively. We used linear and Cox regression to relate plasma concentrations of metabolites and lipids to echocardiographic parameters; CHF and its subtypes heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF); and sleep indices. Adenine dinucleotide phosphate (ADP) associated with left ventricular (LV) fractional shortening; phosphocreatine with LV wall thickness; lysosomal storage molecule sphingomyelin 18:2 with LV mass; and nicotine metabolite cotinine with time spent with an oxygen saturation less than 90% (ß = 2.3 min, P = 2.3 × 10-5 ). Pro-hypertrophic metabolite hydroxyglutarate partly mediated the association between LV wall thickness and HFpEF. Central sleep apnoea was significantly associated with HFpEF (P = 0.03) but not HFrEF (P = 0.5). There were three significant metabolite canonical variates, one of which conferred protection from cardiovascular death [hazard ratio = 0.3 (0.11, 0.81), P = 0.02]. CONCLUSIONS: Energetic metabolites were associated with cardiac function; energy- and lipid-storage metabolites with LV wall thickness and mass; plasma levels of nicotine metabolite cotinine were associated with increased time spent with a sleep oxygen saturation less than 90%, a clinically significant marker of outcome, indicating a significant hazard for smokers who have sleep apnoea.


Subject(s)
Heart Failure , Sleep Apnea Syndromes , Adult , Aged , Echocardiography , Female , Heart Ventricles/diagnostic imaging , Humans , Male , Middle Aged , Sleep Apnea Syndromes/complications , Stroke Volume
18.
Waste Manag Res ; 28(10): 865-71, 2010 Oct.
Article in English | MEDLINE | ID: mdl-19710110

ABSTRACT

Some samples of semi-dry flue gas desulfurization (FGD) ash were taken from sinter gas of a steel factory. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses were employed to identify the samples in order to investigate their physical and chemical characteristics. The results show that semi-dry FGD ash from a steel factory is stable under atmospheric conditions. It has irregular shape, a smooth surface and loose construction. The size of FGD ash particles is around 0.5-25 µm, the average size is about 5 µm and the median diameter is 4.18 µm. Semi-dry FGD ash from a steel factory consists of CaSO3, CaSO4, CaCO3, some amorphous vitreous material and unburned carbon. An experimental method was found to study the oxidation characteristics of ash. A prediction model of the oxidation efficiency was obtained based on response surface methodology. The results show that not only the temperature, but also gas:solid ratio, play an important role in influencing the oxidation efficiency. The interactions of the gas:solid ratio with temperature play an essential role. An improved response surface model was obtained which can be helpful to describe the degree of oxidation efficiency of semi-dry FGD ash.


Subject(s)
Industrial Waste , Steel/chemistry , Desiccation , Oxidation-Reduction , Particle Size , Temperature
20.
Chemosphere ; 258: 127420, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32947658

ABSTRACT

To reduce nitrogen oxides (NOx) emissions in the combustion process, the structure and parameters of a 4500 t d-1 precalciner were optimized. The precalciner model was established using ANSYS FLUENT software (version 14.5). The effects of raw material angle, tertiary air velocity, and tertiary air temperature on NO concentration were studied. A Box-Behnken design (BBD) with three factors was employed to establish a two-order response model based on response surface methodology. The results showed that the simulated total NO concentration at outlet was 526 ppm. Compared to the monitoring data of 496 ppm, the error was within an acceptable range. The raw material angle primarily affected the generated location and rate of NO. The NO concentration at the precalciner outlet increased from 124 ppm to 220 ppm, when the tertiary air velocity increased from 22 m s-1 to 38 m s-1. When the temperature was 1123 K, the NO concentration rose to the highest value of 211 ppm. The interaction between the tertiary air velocity and tertiary air temperature was insignificant, while the other interactions were significant (P < 0.05). Finally, a new response surface model was obtained through optimization, which can accurately predict NO concentration. The optimum conditions for low NOx combustion were a raw material angle of 70°, tertiary air velocity of 26 m s-1, and tertiary air temperature of 1280 K.


Subject(s)
Air Pollutants/analysis , Nitrogen Oxides/analysis , Nitrogen Oxides/chemistry , Temperature
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