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ObjectivesUnder the background of the “dual carbon” strategic goal, the demand for flexible regulation resources in the power system has significantly increased after the large-scale integration of new energy generation into the grid. At present, the coal-fired power is the main flexible resource on the power side with the ability to scale up peak shaving. Since 2016, the major domestic power generation companies have implemented a certain scale of flexibility transformation of coal-fired power units. Therefore, it is necessary to summarize and analyze the problems existing in the actual operation and maintenance of the unit after flexibility transformation.MethodsThe technical route, investment cost and actual operation of several coal-fired power units with flexible transformation in a company were statistically analyzed.ResultsAfter the flexibility improvement and transformation of the active coal-fired power generation unit, the minimum power generation output of the advanced unit can be reduced to 18%Pe (Pe is rated load) level, the load change rate with 20%Pe~30%Pe can reach 1.8%Pe/min, and an average unit capacity investment is 101 yuan/kW. In addition, under flexible operating conditions, the coal consumption of coal-fired power units after the transformation has significantly increased.ConclusionsSuggestions are put forward for the operation, maintenance and further work of coal-fired power units under flexible operating conditions. The research results provide reference and inspiration for the flexibility improvement and transformation of existing coal-fired power units.

A type of reduced graphene oxide (rGO)/SnIn4S8 (SIS) nanocomposites was successfully fabricated by a facile and efficient microwave-assisted method. Their morphology, structure, composition, and optical performance were investigated by different analytical techniques, respectively. The results indicated that rGO had an important effect on the structure of photocatalysts. As the content of rGO increases, the unchin-like microsphere structure of rGO/SIS evolved gradually into aggregated nanosheet structure. The photocatalytic degradation experiments were carried out under visible light irradiation. The results demonstrated rGO/SIS-2 nanocomposites exhibited higher photocatalytic activity toward the degradation of RhodamineB than that of SIS, rGO/SIS-1 as well as rGO/SIS-3. Meanwhile, the mineralization efficiency of Rhodamine B (RhB) can reach up to 73.8% within 30 min. Interestingly, rGO/SIS-2 nanocomposites exhibited excellent recycle stability with 96% removal efficiency of RhB after three cycles. The enhanced photocatalytic activity of rGO/SIS-2 nanocomposites should be attributed to the strong interaction of rGO and SIS, the decrease of band gap energy, the enhanced visible light absorption, and excellent electrons’ mobility of rGO, thereby promoting charge separation. Finally, the mechanism of rGO/SIS nanocomposites for the degradation of RhB has been also proposed. This work provides a facile and efficient pathway to prepare SIS-based nanocomposites with enhanced catalytic efficiency by combining the advantages of microwave-assisted heating and incorporating carbon-based nanomaterials for the degradation of organic pollutants in visible light irradiation.

Objective To investigate the role and mechanism of NLRP3/Caspase-1/IL-1β inflammasome pathway in the formation of aortic dissection in mice. Methods Fifty male C57BL/6 mice (3 weeks old, body weight 10~13 g) were divided into control group (n=10, normal diet), β-aminopropionitrile (BAPN) group [n=20, drink water containing 1 g/(kg·d) BAPN], and BAPN+ MCC950 group [n=20, drink water containing 1 g/(kg·d) BAPN and intraperitoneal injection of 20 mg/(kg·d) NLRP3 inhibitor, MCC950] by random sampling. Water intake, body weight, incidence of aortic dissection and aortic dissection-related mortality were recorded. The inflammatory infiltration in the aorta was observed with HE staining, elastic fiber breakage was observed by elastic Van Gieson (EVG) staining, average fluorescence intensity of NLRP3, IL-1β, α-SMA and OPN was detected by immunofluorescence assay, and protein expression levels of NLRP3, Caspase-1, ASC, IL-1β, α-SMA and OPN were measured with Western blotting. Results No aortic dissection or death was observed in the control group. The BAPN group had an incidence of aortic dissection of 80%, aortic dissection-related mortality of 35%, and obvious broken elastic fibers and inflammatory infiltrate in the aortic wall, and increased expression levels of NLRP3, Caspase-1, ASC and IL-1β, decreased contractile α-SMA and increased synthetic protein OPN when compared with the control group (P < 0.05). While MCC950 treatment decreased the incidence of aortic dissection (80% vs 35%, P=0.004) and aortic dissection-related mortality (35% vs 15%, P=0.144), alleviated the broken elastic fibers and inflammatory infiltrate in the aortic wall, and down-regulated the expression of NLRP3, Caspase-1, ASC and IL-1β, enhanced contractile α-SMA and decreased the synthetic protein when compared with the BAPN group (P < 0.05). Conclusion The occurrence of aortic dissection in mice is associated with activation of NLRP3/Caspase-1/IL-1β inflammasome pathway. NLRP3 inhibitor, MCC950, can reduce the occurrence of aortic dissection and show a protective effect on blood vessels.

Objective·To study early expression levels of serum heparin-binding protein (HBP) and its potential value in early alarming for prognosis and occurrence of sepsis in patients with severe burns.Methods·Retrospective analysis was performed on medical records of 52 severely burned patients admitted to the Department of Burn and Plastic, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine during January 2021 to May 2023. General data of patients on gender, age, total burn area, body mass index (BMI), and whether endotracheal intubation or incision was performed were collected. The level of HBP, serum procalcitonin (PCT), serum C-reactive protein (CRP) and the count of white blood cells within 48 h of admission were collected. The scores of acute physiological and chronic health assessment evaluation Ⅱ (APACHE Ⅱ) and sequential organ failure assessment (SOFA) within 48 h of admission were collected. Patients were divided into death group and survival group according to the status at discharge. According to whether sepsis occurred during hospitalization, the patients were divided into sepsis group and non-sepsis group. According to whether shock occurred, the septic patients were divided into sepsis without shock group and septic shock group. Risk factors for death, sepsis, and septic shock in severely burned patients were analyzed by using Logistic regression models. Receiver operator characteristic (ROC) curve analysis was established to study risk factors, which may alarm the occurrence of poor prognosis, sepsis, and septic shock.Results·Compared with the survival group, patients in the death group were older, and the difference was statistically significant (P=0.036). Differences in burn area and whether tracheal intubation or tracheotomy was performed were statistically significant in patients with or without sepsis (P=0.011, P=0.001). Compared with the survival group, the serum HBP levels were higher in the death group, and the difference was statistically significant (P=0.002). Compared with the non-sepsis group, patients in the sepsis group had higher levels of serum HBP, APACHE Ⅱ scores, and SOFA scores, and the differences were statistically significant (all P

Objective: To establish a new accurate method for the determination of mineral oil saturated hydrocarbon （MOSH） in infant formula by solid phase extraction combined with gas chromatography-Flame Ionization Detection （SPE-GC-FID）. Methods: Different extraction methods such as soaking extraction, oscillating extraction, ultrasonic assisted extraction, liquid-liquid extraction were used to extract MOSH from infant formula milk powder, and different extraction solvents such as n-hexane, isooctane, benzene, mixed solvents were used to extract MOSH. The optimal extraction method and extraction solvent were determined based on the extraction amount of MOSH. The target compounds purified by AgNO3 SPE column, and finally detected by gas chromatography-Flame Ionization Detection （GC-FID）. Results: The calibration curve of MOSH was linear in the range of 10.0~1 000 μg/mL with correlation coefficient of 0.999 97. The limit of detection was 1.0 mg/kg, and the limit of quantitation was 3.0 mg/kg. The recoveries from spiked samples were 93.3%~103.7%, and the relative standard deviations were 2.3%~5.9%. The MOSH in 8 commercially available infant formula was detected by the established method, and the results were between 1.06 and 9.83 mg/kg, indicating that there was a certain risk of MOSH contamination in infant formula. Conclusion: This method is accurate, sensitive, and suitable for the detection of MOSH in infant formula.

Objective: The pretreatment method of through-type solid-phase extraction was improved to be coupled with ultra performance liquid chromatography tandem mass spectrometry for detection of cholic acid，deoxycholic acid and dehydrochloric in eggs. Methods: The samples were extracted by methanol and purified by PRiME HLB，then separated on C18（100 mm×2.1 mm，3.0 μm） column with methanol-0.1% ammonia as the mobile phase for gradient elution. Meanwhile，the samples were quantified by external standard with negative ion select reaction monitoring （SRM） mode. Results: The results showed that the linear relationships of cholic acid （CA），deoxycholic acid （DCA） and dehydrochloric acid（DHCA） were good in the range from 0.5 ng/mL to 500 ng/mL（R2＞0.999）. The detection limits and quantitative limits of CA，DCA and DHCA were 1.0 μg/kg and 3.3 μg/kg. The average recovery of CA，DCA and DHCA from 1.0~10 μg/kg were 93.7%~102.5%，with the RSD of 1.8%~9.2%. 30 batches of randomly selected eggs were tested, and cholic acid was detected in all 28 batches of samples. Conclusion: This method is rapid with high sensitivity，accuracy，and it can be used as a method for the determination of cholic acid and derivative residues in eggs.

Aiming at the problems of slagging and high temperature corrosion of water wall in a 1 000 MW ultra-supercritical double tangential boiler, the mechanism of slagging and high temperature corrosion of boiler was analyzed by X-ray diffraction (XRD) and X-ray fluorescence (XRF).The results show that the presence of sodium and calcium in coal reduces the ash melting point of coal, causing boiler slagging. Sulfide-type high temperature corrosion is the main type of high temperature corrosion of the boiler. Through coal blending optimization and air distribution adjustment, the coal quality feeding into the furnace and the air distribution mode of the burner were optimized. The results show that selecting low-sulfur and low-slagging coal for blending can effectively alleviate the problem of slagging in the furnace. The increase of the total air volume of the boiler and the reasonable adjustment of the secondary air distribution of the burner can effectively reduce the concentration of the reducing atmosphere in the furnace, and alleviate the problem of high temperature corrosion in the furnace. The prediction results of boiler corrosion tendency by numerical simulation method show that the high-temperature corrosion should be further prevented in the hot corner area of the furnace by adding adherent wind or water wall spraying.

Under the production mode of small-batch and multi-item, the recognition of yarn-dyed fabric patterns is a crucial task in the textile industry. In this article, an automatic recognition system based on pixel-level features is proposed to recognize the density, the weave pattern, and the color pattern. In this system, the fabric images are captured by a scanner. First, a method based on the Hough transform is used to correct the skew of the yarns, including warp and weft. Second, the yarns and nodes are located in the enhanced images with a brightness-projection method. The density can be calculated by using the results. Then, the type of each node is identified based on the boundary information. We can obtain the weave pattern after knowing the type of each node. Finally, the fuzzy C-means algorithm is used to determine the color of each node, and thus we obtain the color pattern of the yarn-dyed fabric. Experimental results demonstrate that the proposed recognition system is effective for detecting the structural parameters of yarn-dyed fabric.

Objective: This study aimed to establish a method for the simultaneous determination of 80 veterinary drugs including quinolones, sulfonamides, receptor agonists, glucocorticoids, macrolides, tetracyclines, antiviral drugs in chicken by QuEChERS-ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS）. Methods: The samples were extracted by 1% formic acid acetonitrile aqueous solution, purified by QuEChERS multi-veterinary drug residue purification column, detected by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS） multi-reaction monitoring mode, and quantified by matrix standard curve external standard method. Results: The results showed that 80 kinds of veterinary drugs were highly responsive under specific mass spectrometry conditions, and the samples were sensitive to detection under the conditions of mass spectrometry without interference of foreign peaks. The correlation coefficient of 80 drugs were greater than 0.99 in the range of 5.0~100 μg/L, with good linearity. The detection limit of 80 veterinary drugs were 1.0 μg/kg. The average recovery of spiked concentration of 2.0, 5.0, 10.0 μg/kg in the sample was 62.2%~106.8%; RSD was 2.07%~10.85%. Conclusion: The recovery rate of 80 drugs in the samples conformed to the standard requirements of GB/T 27404—2008 Code for Laboratory Quality Control-Physical and Chemical Testing of Food. The method was suitable for the screening and determination of 80 veterinary drug residues in chicken.

This case report describes a 47-year-old woman with systemic lupus erythematosus (SLE) complicated by Libman–Sacks endocarditis (LSE) who developed multiple organ dysfunction after mitral valve replacement surgery. The patient presented with a 5-day history of cough, sputum, and fever. Transthoracic echocardiography showed significant vegetations on the mitral valve. Biopsy was performed, and the pathological diagnosis was SLE complicated by LSE. After the mitral valve replacement surgery, the patient developed clinical manifestations of hepatic and renal dysfunction, cardiopulmonary failure, oliguria, and shock. The clinical symptoms significantly improved after administration of mechanical ventilation, continuous renal replacement therapy, plasma exchange, anti-inflammatory and anti-infection treatments, immunomodulatory and immunosuppressive therapies, and low-molecular-weight heparin anticoagulation. Multiple organ dysfunction after mitral valve replacement in patients with SLE complicated by LSE has rarely been reported. This report discusses the clinical manifestations, pathogenesis, and treatment of this severe complication. We hope the sharing of our experience in this case will provide a clinical basis for the treatment of severe multiple organ dysfunction after mitral valve replacement in patients with SLE complicated by LSE.

IntroductionAs the top 3 cancer in terms of incidence and mortality, the first-line treatment for CRC includes FOLFOX, FOLFIRI, Cetuximab or immunotherapy. However, the drug sensitivity of patients to regimens is different. There has been increasing evidence that immune components of TME can affect the sensitivity of patients to drugs. Therefore, it is necessary to define novo molecular subtypes of CRC based on TME immune components, and screen patients who are sensitive to the treatments, to make personalized therapy possible. MethodsWe analyzed the expression profiles and 197 TME-related signatures of 1775 patients using ssGSEA, univariate Cox proportional risk model and LASSO-Cox regression model, and defined a novo molecular subtype (TMERSS) of CRC. Simultaneously, we compared the clinicopathological factors, antitumor immune activity, immune cell abundance and differences of cell states in different TMERSS subtypes. In addition, patients sensitive to the therapy were screened out by correlation analysis between TMERSS subtypes and drug responses.ResultsCompared with low TMERSS subtype, high TMERSS subtype has a better outcome, which may be associated to higher abundance of antitumor immune cell in high TMERSS subtype. Our findings suggested that the high TMERSS subtype may have a higher proportion of respondents to Cetuximab agent and immunotherapy, while the low TMERSS subtype may be more suitable for treatment with FOLFOX and FOLFIRI regimens.DiscussionIn conclusion, the TMERSS model may provide a partial reference for the prognosis evaluation of patients, the prediction of drug sensitivity, and the implementation of clinical decision-making.

Objective: This study aimed to establish a method for quick determination of 3 kinds ofmethylimidazole compounds in food flavor. Methods: The food flavor was extracted with 5% trichloroacetic acid solution and purified with PCX mixed cationic solid phase extraction column. Finally, the qualitative and quantitative analysis was carried out by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) and internal standard method. Results: The linear relationship between the three methyl imidazole compounds was good in the range of 5.0~400.0 ng/mL, with correlation coefficient R2≥0.997. The limits of detection were 0.030~0.450 μg/kg and the limits of quantification (LOQ) were 0.10~1.50 μg/kg. The recoveries of three methylimidazole ranged from 82.8% to 111.7%, and the relative standard deviations (RSDS) ranged from 1.3% to 9.3%. Conclusion: The method is simple, efficient and accurate, and can be used for the quantitative determination of 1-methylimidazole, 2-methylimidazole, 4-methylimidazole in food flavor.

Objective: This study aimed to establish a new method for the determination of matrine and oxymatrine in honey by UPLC-MS/MS. Methods: The honey was dissolved in water, and the liquid-liquid extraction pretreatment technology was adopted. The extraction was achieved using ammonia-acetonitrile, with the addition of sodium sulfate to induce a salting out effect. Chromatographic separation was achieved on Inspire HILIC column in the mobile phase composition of acetonitrile and 0.1% formic acid-5 mmol/L ammonium acetate buffer. Mass Spectrometry was carried out under the multiple reaction monitoring (MRM) mode with positive electrospray ionization (ESI+) and external standard method for quantitative analysis. Results: The linear relationship between matrine and oxymatrine was observed in the range of 1~100 ng/mL, with correlation coefficients higher than 0.998. The detection limit and quantitative limit of matrine and oxymatrine in honeywere 0.1 μg/kg and 0.3 μg/kg, respectively. The average recoveries of matrine and oxymatrine were 90.9%~95.1% and 80.9%~84.3%, respectively, at the spiked levels of 1, 10 and 100 μg/kg, with the relative standard deviations (RSDS)＜ 10% (n=6). The validated method was then successfully applied to the determination of matrine and oxymatrine in 45 commercially available honey, and the results showed that the detection probability and content of matrine and oxymatrine in acacia honey were relatively high. Conclusion: The established method is accurate, rapid, and sensitive, Moreover, a simultaneous preparation of multiple sample extracts is available, and it can used for the routine determination of matrine and oxymatrine in honey.

With continuing breakthroughs in computational chemistry theory and substantial improvement of computation hardware performance, great progresses have been made in recent years in first principle-based prediction of 1H and 13C chemical shifts of organic molecules. Some methods have even been gradually applied for accurate prediction in complex molecular systems. In this paper, a density functional theory-based high-precision on-line chemical shift prediction platform for organic molecules is established, which provides on-line interactive service of chemical shift prediction for molecules with a molecular weight less than 800. The platform accelerates the mapping between nuclear magnetic resonance (NMR) spectra and molecular structures, and provides a powerful tool for efficient assignment of NMR spectra and accurate analysis of organic molecular structure.

A series of novel perfluoropropan-2-yl-based quinoline derivatives was designed and synthesized utilizing tebufloquin as the lead compound. The structures of all the newly synthesized compounds were confirmed by spectroscopic data 1HNMR, MS and elemental analysis. The results of bioassay indicated that these compounds exhibited potent fungicidal activities against Erysiphe graminis. Especially, compound 8c displayed excellent activity with EC50 value at 1.48 mg / L, which was better than that of the commercialized fungicide --- tebufloquin. The structure-activity relationship for these new compounds was also discussed.

SiCp/Al composites were prepared by pressureless infiltration using domestic abrasive grade SiC particles with average diameters in the range of 60-80μm. Ultrasonic cleaning method was used to investigate the effect of the surface adsorbate of SiC particles on the infiltration process and mechanical property of the SiCp/Al composite. The results show that all types of the studied SiC particles are adhered by low mass fractions of the adsorbate(μm)and,in certain cases,low fraction of carbon. That surface adsorbate has a negative effect on the wettability between SiC particles and molten alloy,resulting in the reduced density and mechanical property of the infiltrated SiCp/Al composite. Ultrasonic cleaning process can effectively wipe off the adsorbate,and,by using the cleaned SiC particles,the success rate of the infiltration can be raised from 25% to 100%. Correspondingly, the flexure strength and elasticity modulus of the composites are improved from 320MPa to 390MPa and from 203GPa to 232GPa, respectively.

Aiming at the existing heavy-haul railway, bridges hardly meet the transportation requirements. Based on the spatial vibration calculation model of the freight train–track–bridge (FTTB) system, the FTTB spatial vibration model under the condition of auxiliary steel beam reinforcement is established. Besides, according to the random analysis method of train derailment energy, coming up with an evaluation method of auxiliary steel beam reinforcement is based on safety and dynamic response, which is used to discuss the train safety and the change law of FTTB system vibration response. The results show that the derailment resistance of the FTTB system is increased by 22.6% after the auxiliary steel beam is reinforced. Compared with the previous speed (115.56 km/h), the speed is 132.73 km/h after the auxiliary steel beam reinforcement; at the same time, the allowable limit speed increases from 92.49 km/h to 106.18 km/h. In addition, the reinforcement of the auxiliary steel beam can not only effectively reduce the lateral vibration response of the FTTB system under the action of empty wagon but also effectively decline the vertical vibration response of the FTTB system under the action of the loaded wagon, which can meet the stability requirement for running at the speed of 90 km/h. In summary, the reinforcement of auxiliary steel beams can improve the running safety of trains, reduce the vibration response of the FTTB system, and meet the requirements of operation stability.

Introduction. We studied the impact of vibratory stimulation on the electrophysiological features of digital sensory nerve action potential (SNAP). Methods. The antidromic digit 3 SNAP was recorded in 19 healthy adults before, during, and after applying a vibration to either 3rd or 5th metacarpal phalangeal joint (MCPJ) at 60 Hz and amplitude of 2 mm. 100% supramaximal stimulus intensity was performed in 5 subjects (randomly selected from the 19 subjects) where the SNAP sizes were recorded. Results. The amplitude of digit 3 SNAP declined to 58.9±8.6% when a vibration was applied to MCPJ digit 3. These impacts did not change by increasing the electrical stimulus intensity. The SNAP regained its baseline value immediately after the cessation of vibration stimulation. The magnitude of size reduction of digit 3 SNAP was less when vibration was moved to from MCPJ of digit 3 to MCPJ of digit 5. Discussion. The marked drop of the SNAP size during vibratory stimulation reflects the decreased responsiveness of Aβ afferents to electrical stimulation, which deserve further investigation in the study of focal vibration in neurorehabilitation.

Salicylhydroxamic acid is a novel flotation reagent,this paper studied O3 oxidation treatment of salicylhydroxamic acid in simulated flotation wastewater.Meanwhile,the possible degradation pathway of salicylichydroxamic acid was deduced through ultraviolet spectrophotometry,infrared spectrum and high performance liquid chromatography.The experimental results showed that the removal efficiency of salicylichydroxamic acid treated by O3 oxidation was obviously.When initial concentration of salicylhydroxamic was 50 mg/L,pH value was 8,ozone concentration was 1.3 mg/L and reaction time was 15min,the removal rate was greater than 90%,but the mineralization rate was just 19.99%.Through the analysis of intermediates,the degradation pathway of salicylhydroxamic acid was preliminarily concluded as:salicylhydroxamic acid → salicylic acid+hydroxylamine→ catechol → maleic → small molecule organic acid+carbon dioxide+water.