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CONTEXT: This study primarily investigates the changes in carbon adsorption capacity and hydrogen adsorption capacity on the anode catalyst surface when using methane fuel and mixed gas fuel as the anode fuel for SOFC systems. To reduce the carbon adsorption capacity of the commonly used anode catalyst-nickel-based catalysts-towards hydrocarbon fuels, copper and gold are doped into the nickel-based catalysts to compare the effects on carbon and hydrogen adsorption capacities. Moreover, aside from calculating the carbon and hydrogen adsorption capacities, this project also evaluates the impact of mixed gas effects and doping effects on SOFC performance through the analysis of hydrogen diffusion coefficients and performance polarization curves. The findings reveal a noteworthy enhancement in the diffusion coefficient of syngas within the Au-doped Ni catalyst, showing an improvement of up to 45.46% at 973 K. Furthermore, the electrical power generated by syngas in the Au-doped Ni catalyst at 973 K demonstrates an increase of up to 12.06%. METHODS: This study primarily employs DFT to calculate the carbon and hydrogen adsorption energies on methane, utilizing CASTEP for the calculations. During these calculations, the adsorption energy is determined through a three-layer surface approach, in conjunction with the Kohn-Sham equations, combining the Generalized Gradient Approximation and ultrasoft pseudopotentials for TS-search calculations. On the other hand, this project will analyze the diffusion coefficient of hydrogen on the anode catalyst using MD methods combined with the ReaxFF potential field, with GULP being utilized to complete all dynamics calculation theories. Finally, the project will analyze the performance of SOFC cells, incorporating relevant numerical equations with Matlab for numerical analysis.

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Objective To investigate the baseline clinical characteristics,ascending aortic root anatomical characteristics,and related factors of the surgical strategy of patients with new-onset conduction disturbance(NOCD)after transcatheter aortic valve replacement(TAVR)with self-expanding valve(SEV)implantation.Methods A retrospective study was conducted on 245 patients who underwent TAVR at the Xiamen Cardiovascular Hospital Xiamen University between December 2014 and November 2022.According to the inclusion and exclusion criteria,167 patients with SEV implantation during surgery were continuously included.They were divided into tricuspid aortic valve group(TAV group,113 cases)and bicuspid aortic valve group(BAV group,54 cases)according to aortic valve morphology.The TAV group was divided into NOCD group(43 cases)and non NOCD group(70 cases)according to postoperative electrocardiogram characteristics.The BAV group was divided into NOCD group(16 cases)and non NOCD group(38 cases).Collect clinical data such as preoperative electrocardiogram and ascending aortic root CT angiography from patients.Results The right-non valvular calcification quantification(P=0.005)in the non-NOCD group was significantly greater than that in the NOCD group,but the aortic angle(P=0.002)was smaller in TAV patients.Multivariate analysis suggested that the risk of NOCD after TAVR is reduced by 2.6％for every 10 mm3 increase in right-non valvular calcification in patients(OR 0.974,P=0.039),the risk of postoperative NOCD nearly 7.3％for every degree increase in aortic angulation(OR 1.073,P=0.003).In BAV patients the increase of the risk of NOCD after TAVR is nearly 3.3％for every l ms increase in preoperative PR interval(OR 1.033,P=0.041),the risk of NOCD is reduced by 6.6％for every 10 mm3 increase in calcification quantification in the right coronary valve area(OR 0.934,P=0.013).Conclusions In TAV patient,right-non valvular calcification may have a protective effect on the cardiac conduction system,but a larger aortic angle increases the risk of NOCD.In BAV patients,a longer preoperative PR interval is a risk factor for NOCD,and the right coronary valve area may protect the cardiac conduction system.

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Chronic pain reduces the quality of life and ability to function of individuals suffering from it, making it a common public health problem. Neuroinflammation which is mediated by the Nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation in the spinal cord participates and modulates chronic pain. A chronic inflammatory pain mouse model was created in the current study by intraplantar injection of complete Freund's adjuvant (CFA) into C57BL/6J left foot of mice. Following CFA injection, the mice had enhanced pain sensitivities, decreased motor function, increased spinal inflammation and activated spinal astrocytes. Emodin (10 mg/kg) was administered intraperitoneally into the mice for 3 days. As a result, there were fewer spontaneous flinches, higher mechanical threshold values and greater latency to fall. Additionally, in the spinal cord, emodin administration reduced leukocyte infiltration level, downregulated protein level of IL-1ß, lowered histone deacetylase (HDAC)6 and NLRP3 inflammasome activity and suppressed astrocytic activation. Emodin also binds to HDAC6 via four electrovalent bonds. In summary, emodin treatment blocked the HDAC6/NLRP3 inflammasome signaling, suppresses spinal inflammation and alleviates chronic inflammatory pain.

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BACKGROUND: In recent decades, the prevalence of metabolic diseases, particularly diabetes, hyperlipidemia, obesity, and non-alcoholic fatty liver disease (NAFLD), has increased dramatically, causing great public health and economic burdens worldwide. Traditional Chinese medicine (TCM) serves as an effective therapeutic choice. Xiao-Ke-Yin (XKY) is a medicine and food homology TCM formula consisting of nine "medicine and food homology" herbs and is used to ameliorate metabolic diseases, such as insulin resistance, diabetes, hyperlipidemia and NAFLD. However, despite its therapeutic potential in metabolic disorders, the underlying mechanisms of this TCM remain unclear. This study aimed to evaluate the therapeutic effectiveness of XKY on glucolipid metabolism dysfunction and explore the potential mechanisms in db/db mice. METHODS: To verify the effects of XKY, db/db mice were treated with different concentrations of XKY (5.2, 2.6 and 1.3 g/kg/d) and metformin (0.2 g/kg/d, a hypoglycemic positive control) for 6 weeks, respectively. During this study, we detected the body weight (BW) and fasting blood glucose (FBG), oral glucose tolerance test (OGTT), insulin tolerance test (ITT), daily food intake and water intake. At the end of the animal experiment, blood samples, feces, liver and intestinal tissue of mice in all groups were collected. The potential mechanisms were investigated by using hepatic RNA sequencing, 16 S rRNA sequencing of the gut microbiota and metabolomics analysis. RESULTS: XKY efficiently mitigated hyperglycemia, IR, hyperlipidemia, inflammation and hepatic pathological injury in a dose dependent manner. Mechanistically, hepatic transcriptomic analysis showed that XKY treatment significantly reversed the upregulated cholesterol biosynthesis which was further confirmed by RT-qPCR. Additionally, XKY administration maintained intestinal epithelial homeostasis, modulated gut microbiota dysbiosis, and regulated its metabolites. In particular, XKY decreased secondary bile acid producing bacteria (Clostridia and Lachnospircaeae) and lowered fecal secondary bile acid (lithocholic acid (LCA) and deoxycholic acid (DCA)) levels to promote hepatic bile acid synthesis by inhibiting the LCA/DCA-FXR-FGF15 signalling pathway. Furthermore, XKY regulated amino acid metabolism including arginine biosynthesis, alanine, aspartate and glutamate metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and tryptophan metabolism likely by increasing Bacilli, Lactobacillaceae and Lactobacillus, and decreasing Clostridia, Lachnospircaeae, Tannerellaceae and Parabacteroides abundances. CONCLUSION: Taken together, our findings demonstrate that XKY is a promising "medicine food homology" formula for ameliorating glucolipid metabolism and reveal that the therapeutic effects of XKY may due to its downregulation of hepatic cholesterol biosynthesis and modulation of the dysbiosis of the gut microbiota and metabolites.

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Tuberculosis (TB) is an ancient infectious disease. Before the availability of effective drug therapy, it had high morbidity and mortality. In the past 100 years, the discovery of revolutionary anti-TB drugs such as streptomycin, isoniazid, pyrazinamide, ethambutol and rifampicin, along with drug combination treatment, has greatly improved TB control globally. As anti-TB drugs were widely used, multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis emerged due to acquired genetic mutations, and this now presents a major problem for effective treatment. Genes associated with drug resistance have been identified, including katG mutations in isoniazid resistance, rpoB mutations in rifampin resistance, pncA mutations in pyrazinamide resistance, and gyrA mutations in quinolone resistance. The major mechanisms of drug resistance include loss of enzyme activity in prodrug activation, drug target alteration, overexpression of drug target, and overexpression of the efflux pump. During the disease process, Mycobacterium tuberculosis may reside in different microenvironments where it is expose to acidic pH, low oxygen, reactive oxygen species and anti-TB drugs, which can facilitate the development of non-replicating persisters and promote bacterial survival. The mechanisms of persister formation may include toxin-antitoxin (TA) modules, DNA protection and repair, protein degradation such as trans-translation, efflux, and altered metabolism. In recent years, the use of new anti-TB drugs, repurposed drugs, and their drug combinations has greatly improved treatment outcomes in patients with both drug-susceptible TB and MDR/XDR-TB. The importance of developing more effective drugs targeting persisters of Mycobacterium tuberculosis is emphasized. In addition, host-directed therapeutics using both conventional drugs and herbal medicines for more effective TB treatment should also be explored. In this article, we review historical aspects of the research on anti-TB drugs and discuss the current understanding and treatments of drug resistant and persistent tuberculosis to inform future therapeutic development.

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Despite the achievements obtained worldwide in the control of tuberculosis in recent years, many countries and regions including China still face challenges such as low diagnosis rate, high missed diagnosis rate, and delayed diagnosis of the disease. The discovery strategy of tuberculosis in China has changed from "active discovery by X-ray examination" to "passive discovery by self-referral due to symptoms", and currently the approach is integrated involving self-referral due to symptoms, active screening, and physical examination. Active screening could help to identify early asymptomatic and untreated cases. With the development of molecular biology and artificial intelligence-assisted diagnosis technology, there are more options for active screening among the large-scale populations. Although the implementation cost of a population-based active screening strategy is high, it has great value in social benefits, and active screening in special populations can obtain better benefits. Active screening of tuberculosis is an important component of the disease control. It is suggested that active screening strategies should be optimized according to the specific conditions of the regions to ultimately ensure the benefit of the tuberculosis control.

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Currently three dimensional bio-printing technology has become one of the hot topics for tissue engineering tracheal grafting.Different biomaterials have their own performance advantages in the preparation and regeneration of tracheal scaffolds.It is particularly imperative to seek natural or polymeric materials with excellent profiles of printability, structural stability and biocompatibility to enable neo-cartilage formation, neo-epithelialization and neo-vascularization of tissue engineering trachea grafting.This review summarized the shortcomings and challenges of classifying and applying materials for three dimensional bio-printing tissue engineering trachea, aiming to provide new rationales for researches and applications of tissue engineering tracheal grafting.

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Objective To investigate the efficacy and safety of stereotactic body radiotherapy(SBRT)combined with camrelizumab and apatinib in treatment of advanced hepatocellular carcinoma(HCC).Methods The clinical data were retrospectively analyzed of 85 patients with advanced HCC treated in the Fifth Affiliated Hospital of Zhengzhou University and People's Hospital of Zhengzhou from January 2019 to September 2021.They were divided into observation group(n=31,SBRT combined with camrelizumab and apatinib)and control group(n=54,treated with camrelizumab and apatinib)according to whether they received SBRT.The propensity score matching(PSM)was used to balance the influence of confounding factors.The objective remission rate(ORR)and disease control rate(DCR)were compared between the two groups.The 6-month overall survival rate,1-year overall survival rate and progression-free survival(PFS)were compared between the two groups by Kaplan-Meier method.The safety of the two groups was evaluated by Common Terminology Criteria for Adverse Events(CTCAE)version 5.0.Results Before PSM,there were significant differences in age(P=0.043),number of extrahepatic metastasis(P=0.028),and previous surgical treatment(P=0.038)between the two groups.After PSM,there was no significant difference in baseline characteristics between the two groups(P>0.05).After PSM,27 cases were included in each groups,and three months after treatment,the ORR in observation group and control group were 66.7%and 29.6%,respectively,showed difference with statistically significant(P=0.006);and the DCR in the both groups were 96.3%and 85.2%respectively,showed no statistically significant difference(P=0.175).There were statistical differences in 6-month overall survival rate(96.3%vs.80.9%,P=0.001),1-year overall survival rate(75.0%vs.61.4%,P=0.034)and median PFS(8 months vs.5 months,P=0.003)between the observation group and control group.Multi-factor Cox regression analysis showed that baseline alpha-fetoprotein(AFP)≥400 ng/ml was an independent risk factor for affecting the survival of patients with advanced HCC(HR>1,P<0.05),while the triple therapy and previous targeted drugs therapy were the protective factors for the survival of patients with advanced HCC(HR<1,P<0.05).In the observation group,4 patients had grade 3 adverse reactions,and the common adverse reactions were dyspepsia(14.8%).One case of grade 3 adverse reactions occurred in control group,and there was no statistically significant difference in the incidence of adverse reactions between the two groups(P=0.639).Conclusion SBRT combined with camrelizumab and apatinib is a safe and effective treatment for advanced HCC with significant clinical effect and controllable adverse reactions.

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The total bacteria count has been attracting attention as an important pollutant in indoor air, and its standard limit was tightened to 1500 CFU/m3 in "Standards for indoor air quality (GB/T 18883-2022)".The technical contents related to the determination of the indoor air standard limits for total bacteria count were analyzed and studied, including the environmental existence level, exposure status, the health effects and the derivation of the limit value. It also proposed prospects for the future development and revision of quality standards for total bacteria count in indoor air.

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The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. This paper introduced the formulation and revision of the detection methods of the standards for indoor air quality (GB/T 18883-2022), focusing on the revision process, revision principles, main adjustments and technical points of some key indicators to facilitate users to better understand and apply the detection methods in standards for indoor air quality (GB/T 18883-2022).

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The total bacteria count has been attracting attention as an important pollutant in indoor air, and its standard limit was tightened to 1500 CFU/m3 in "Standards for indoor air quality (GB/T 18883-2022)".The technical contents related to the determination of the indoor air standard limits for total bacteria count were analyzed and studied, including the environmental existence level, exposure status, the health effects and the derivation of the limit value. It also proposed prospects for the future development and revision of quality standards for total bacteria count in indoor air.

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The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. This paper introduced the formulation and revision of the detection methods of the standards for indoor air quality (GB/T 18883-2022), focusing on the revision process, revision principles, main adjustments and technical points of some key indicators to facilitate users to better understand and apply the detection methods in standards for indoor air quality (GB/T 18883-2022).

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Chronic pain is the predominant problem for rheumatoid arthritis patients, and negatively affects quality of life. Arthritis pain management remains largely inadequate, and developing new treatment strategies are urgently needed. Spinal inflammation and oxidative stress contribute to arthritis pain and represent ideal targets for the treatment of arthritis pain. In the present study, collagen-induced arthritis (CIA) mouse model was established by intradermally injection of type II collagen (CII) in complete Freund's adjuvant (CFA) solution, and exhibited as paw and ankle swelling, pain hypersensitivity and motor disability. In spinal cord, CIA inducement triggered spinal inflammatory reaction presenting with inflammatory cells infiltration, increased Interleukin-1ß (IL-1ß) expression, and up-regulated NOD-like receptor thermal protein domain associated protein 3 (NLRP3) and cleaved caspase-1 levels, elevated spinal oxidative level presenting as decreased nuclear factor E2-related factor 2 (Nrf2) expression and Superoxide dismutase (SOD) activity. To explore potential therapeutic options for arthritis pain, emodin was intraperitoneally injected for 3 days on CIA mice. Emodin treatment statistically elevated mechanical pain sensitivity, suppressed spontaneous pain, recovered motor coordination, decreased spinal inflammation score and IL-1ß expression, increased spinal Nrf2 expression and SOD activity. Further, AutoDock data showed that emodin bind to Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) through two electrovalent bonds. And emodin treatment increased the phosphorylated AMPK at threonine 172. In summary, emodin treatment activates AMPK, suppresses NLRP3 inflammasome response, elevates antioxidant response, inhibits spinal inflammatory reaction and alleviates arthritis pain.

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The purpose is to coordinate the relationship between innovation and entrepreneurship education (IEE) and professional education. This exploration is based on the entrepreneurial spirit of young entrepreneurs and the re-integration of IEE and music education in colleges. First, the IEE is studied in theory. Then, the basic criteria for integrating IEE and professional education are studied, and 305 students from a music college in Xi'an are taken as the survey sample. The questionnaire is adopted to investigate the current situation of the integration of IEE and professional education. The results show that 52.1% of students believe that IEE is closely related to professional education. In terms of self entrepreneurship awareness, males' awareness of self entrepreneurship is higher than females', and the willingness of self entrepreneurship from freshman to senior is 3.1, 15.5, 26.1, and 30.8%, respectively. For the dominant position in the integrated curriculum, 55.6% hold that professional courses should dominate innovative professional courses, and 25.9% believe that innovation and entrepreneurship courses should be dominated. Besides, 16.5% think that the proportion of the two should be the same, and 2% hold that it doesn't matter. For the enthusiasm of innovative professional courses, only 14.1% of students are very positive. The survey results show that the integration of IEE and professional education needs to be improved, and there is a lack of pertinence and guidance for students of different genders and grades. Students are not clear about the position of IEE and lack enthusiasm. Finally, reasonable suggestions are put forward in view of the above problems. The results are conducive to promoting and accelerating the process of talent training mode combining professional education and IEE. It has a certain reference value for college education and teaching reform.

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Leukoaraiosis (LA) is commonly found in aging healthy people but its pathophysiological mechanism is not entirely known. Furthermore, there is still a lack of effective pathological biomarkers that can be used to identify the early stage of LA. Our aim was to investigate the white matter structural network in asymptomatic patients with the early stage of LA. Tractography data of 35 asymptomatic patients and 20 matched healthy controls (HCs) based on diffusion kurtosis imaging (DKI) were analysed by using graph theory approaches and tract-based spatial statistics (TBSS). Diffusion parameters measured within the ALAs and HCs were compared. Decreased clustering coefficient and local efficiency values of the overall topological white matter network were observed in the ALAs compared with those of the HCs. Participants in the asymptomatic group also had lower nodal efficiency in the left triangular part of the inferior frontal gyrus, left parahippocampal gyrus, right calcarine fissure and surrounding cortex, right temporal pole of the superior temporal gyrus and left middle temporal gyrus compared to the ALAs. Moreover, similar hub distributions were found within participants in the two groups. In this study, our data demonstrated a topologic efficiency abnormalities of the structural network in asymptomatic patients with leukoaraiosis. The structural connectome provides potential connectome-based measures that may be helpful for detecting leukoaraiosis before clinical symptoms evolve.

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BACKGROUND@#To investigate the correlation between the reduction of lung volume and the degree of lung function damage after lobectomy.@*METHODS@#A total of 131 patients (72 males and 59 females) who underwent thoracoscopic lobectomy in the First Affiliated Hospital of Suzhou University from January 2019 to July 2020 (including thoracoscopic resection of left upper lobe, left lower lobe, right upper lobe, right middle lobe and right lower lobe). In order to compare the difference between postoperative pulmonary function and preoperative pulmonary function, the pulmonary function measurements were recorded at 7 days before operation, and 3 months, 6 months and 1 year after operation. Forced expiratory volume in 1 second (FEV1) was used as the main evaluation parameter of pulmonary function. The original lung volume and the remaining lung volume at each stage were calculated by Mimics Research 19.0 software. The correlation between lung volume and lung function was analyzed.@*RESULTS@#FEV1 in postoperative patients was lower than that before operation, and the degree of decline was positively correlated with the resection volume of lung lobes (the maximum value was shown in the left lower lobe group). Significantly, there was no significant difference in the degree of pulmonary function reduction between 3 months, 6 months and 1 year after operation.@*CONCLUSIONS@#The decrease of lung tissue volume after lobectomy is the main reason for the decrease of lung function, especially in the left lower lobe. And 3 months after lobectomy can be selected as the evaluation node of residual lung function.

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Solid dispersion, a dispersion system in which drug molecules are highly dispersed in carrier materials, has been commonly used to improve the solubility and dissolution rate of poorly soluble drugs. The miscibility between drug and carrier is crucial to improve the dissolution performance and stability of solid dispersion. Therefore, the selection of carrier types and the optimization of drug loading are very important. In the current study, the solubility parameter method and Flory-Huggins theory were used to predict the miscibility between olaparib (OLP) and different carriers (VA64, Soluplus, Plasdone S630 and Kollidon K29/32). Besides, the carrier material with good miscibility was experimentally screened by differential scanning calorimetry (DSC). The optimum of drug-carrier ratio was further performed based on the miscibility phase diagram of drug and carrier. Theoretical calculation and experimental evaluation showed that the miscibility of OLP and VA64 was the best, and the drug loading of 30% could meet the requirements of large drug loading and physical stability. Polarizing light microscope, X-ray powder diffraction, DSC and laser confocal Raman spectroscopy exhibited that OLP was amorphous form in the solid dispersion system. Powder dissolution test demonstrated that the solid dispersion showed significantly enhanced dissolution rate in comparison to crystalline OLP. In this study, theoretical calculation and experimental evaluation were used to screen the types of carriers and optimize the drug loading, which provides an efficient strategy for the selection of carrier and the amount used in solid dispersion.

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Background: For hepatocellular carcinoma ("HCC"), the current standard of treatment is hepatic artery embolization, generally through trans-catheter arterial chemoembolization ("TACE"). There are two types: traditional ("conventional" or "cTACE") and microsphere ("DC bead TACE"). Unfortunately, the literature comparing the relative effectiveness of cTACE versus DC bead TACE is inconclusive, partially due to the complexity of HCC and its response to treatment. Data mining is an excellent method to extract meaning from complex data sets. Purpose: Through the application of data mining techniques, to compare the relative effectiveness of cTACE and DC bead TACE using a large patient database and to use said comparison to establish usable guidelines for developing treatment plans for HCC patients. Materials and Methods: The data of 372 HCC patients who underwent TACE in Taichung Veterans General Hospital were analyzed. The chi-square test was used to compare the difference in the effectiveness of the two therapies was compared. Logistic regression was used to calculate the odds ratios. Furthermore, using the C4.5 decision tree, the two therapies were classified into applicable fields. Chi-square test, the t-test, and logistic regression were used to verify the classification results. Results: In Barcelona Clinic Stages A and B cancers, cTACE was found to be 22.7% more effective than DC bead TACE. By using the decision tree C4.5 as a classifier, the effectiveness of either treatment for small tumors was 8.475 times than that for large tumors. DC bead TACE was 3.39 times more successful in treating patients with a single tumor than with multiple tumors. For patients with a single tumor, the chi-square test showed that 100-300 µm microspheres were significantly more effective than 300-500 µm. While these findings provide a reference for the selection of an appropriate TACE approach, we noted that overall accuracy was somewhat low, possibly due to the limited population. Conclusions: We found that data mining could be applied to develop clear guidelines for physician and researcher use in the case of complex pathologies such as HCC. However, some of our results contradicted those elsewhere in the literature, possibly due to a relatively small sample size. Significantly larger data sets with appropriate levels of granularity could produce more accurate results.

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In this study, protein isolate (PI) and purified phenolic extract (PPE) were prepared from Cinnamomum camphora seed kernel (CCSK). The effects of covalent modification of PI by PPE at different concentrations (1, 2, 3, 4 and 5%, w/w) were investigated with respect to structural properties and antioxidant activities of protein. Fifteen bioactive compounds in PPE were tentatively identified by UPLC-ESI-MSn. With the increase of PPE concentration, the turbidity, covalent binding rate, phenolic content and color intensity of the PI-PPE complexes were gradually increased. Fourier transform infrared spectroscopy and circular dichroism spectroscopy analysis showed that the secondary and tertiary structures of the complexes were changed and became greater order than PI. Furthermore, the complexes exhibited stronger thermal stability and antioxidant activities than those of PI. These results suggested that the protein-phenolic covalent complexes obtained from CCSK may have great potential to be used in food formulations as functional ingredients.

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Enzymatic degradation has become the most promising approach to degrading organic ester compounds. In this study, Bacillus licheniformis NCU CS-5 was isolated from the spoilage of Cinnamomum camphora seed kernel, and its extracellular lipase was purified, with a specific activity of 192.98 U/mg. The lipase was found to be a trimeric protein as it showed a single band of 27 kDa in SDS-PAGE and 81 kDa in Native-PAGE. It was active in a wide range of temperatures (5-55 °C) and pH values (6.0-9.0), and the optimal temperature and pH value were 40 °C and 8.0, respectively. The enzyme was active in the presence of various organic solvents, metal ions, inhibitors and surfactants. Both crude and purified lipase retained more than 80% activity after 5 h in the presence of commercial detergents, suggesting its great application potential in detergent industry. The highest activity was found to be towards medium- and long-chain fatty acids (C6-C18). Peptide mass spectrometric analysis of the purified lipase showed similarity to the lipase family of B. licheniformis. Furthermore, it degraded more than 90% 2,4-D butyl ester to its hydrolysate 2,4-D within 24 h, indicating that the novel lipase may be applied to degrade organic ester pesticides.

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