Abstract:To investigate the expression and purification conditions of transmembrane(TM-CXCL16)and soluble(sCXCL16)chemokine CXCL16,and to obtain CXCL16 protein with high expression yield and purity,this study amplified the gene fragments of TM-CXCL16,6×HisTEV-sCXCL16,and sCXCL16-6×His via PCR.These fragments were cloned into the pRSETA0 recombinant expression vector and transformed into the E.coli DH5α expression system,followed by induction with IPTG.Protein expression forms were identified by means of SDS-PAGE and Western blot,and proteins were purified by immobilized metal ion affinity chromatography(IMAC).Results showed that TM-CXCL16 and sCXCL16 proteins were successfully expressed in E.coli DH5α.Optimal expression conditions for TM-CXCL16 were 20 ℃,200 rpm,and 1.0 mM IPTG.Both sCXCL16-N(His-tagged at the N-terminus)and sCXCL16-C(His-tagged at the C-terminus)were expressed after IPTG induction,with the position of the His-tag showing no significant effect on sCXCL16 expression.Expression of sCXCL16-C was slightly higher at 20 ℃ compared to 37 ℃.Furthermore,IPTG concentration(0.1～1.0 mM)had no significant impact on sCXCL16-C expression levels.Analysis of expression forms revealed that sCXCL16-C was expressed in an insoluble form.The results indicate that both TM-CXCL16 and sCXCL16 were successfully expressed in a prokaryotic expression system.However,the sCXCL16 protein was expressed in an insoluble form,and high purity of the sCXCL16-C protein was not achieved using IMAC technology.Further optimization of the elution conditions is required to improve the protein purity.

Abstract:The wet-part production speed of corrugated board lines is an important indicator representing the production efficiency.Its intelligent prediction can guide the enterprises to reasonably arrange the production and enhance the control level of the production line,which is of great significance for the efficient and green production of corrugated board.Firstly,data cleaning is performed on multi-type sampled data.The Bessel filters and quartile statistics methods are used to select the data of production speed in the stable interval,and the production parameters corresponding to B-corrugated and BC-corrugated are extracted respectively.Secondly,a BP neural network(GELU as the activation function)and a LightGBM(Light Gradient Boosting Machine)model are established to predict the production speed of the corrugated board line,and the hyperparameters of the two models are optimized by the Bayesian optimization and grid search respectively.The prediction results of the two models are combined by the grey wolf optimization algorithm(GWO).The results show that compared with the BPNN-XGBoost combined model the proposed method can significantly reduce prediction time while maintaining the same prediction accuracy,which greatly facilitates the online prediction of production speed in corrugated board lines.

Abstract:As the depth of neural networks increases,the problems of the gradient vanishing and the gradient explosion become increasingly prominent.Meanwhile,improving feature reuse rate and reducing computational complexity have emerged as key challenges.This paper proposes a feature extraction network based on shared feature layer,and designs a dynamic iterative update mechanism.This mechanism integrates the output features of all previous layers and those of the current layer,and combines batch channel normalization to improve feature reuse efficiency.The shared feature layer is connected to the backbone network via residual connections,which enables effective feature updating and maintains gradient stability in the process of backpropagation.The experimental results show that the Top-1 error rate of SFLN-152 on ImageNet dataset is 19.00%,which is 11.34%and 5%lower than that of ResNet-152 and DPN-131,respectively.The classification error rates on the CIFAR-10 and CIFAR-100 datasets are 4.77%and 19.85%.

Abstract:To improve the extraction efficiency and quantify the content of protein peptides from Andrias davidianus,ultraviolet spectrophotometry combined with a standard hydroxyproline curve was employed to determine the total hydroxyproline content in the fermentation broth,thereby optimizing the influencing factors in the extraction process.Key process variables,including bacterial concentration,extraction time,bacterial age,and solid-to-liquid ratio,were investigated through single-factor experiments.Results demonstrated that the optimal solid-state fermentation conditions were determined to be:fermentation temperature at 37℃using bacillus subtilis cultured for 18～25 h,fermentation duration of 36～60 h,material-to-liquid ratio of 1:10,and shaking speed at 180 rpm.Under these conditions,hydroxyproline extraction yield reached 21%.Fermentation duration was identified as the most significant factor affecting production yield,followed by material-to-liquid ratio and shaker speed.This study has elucidated the key parameters and their optimal ranges for protein extraction from giant salamander through solid-state fermentation,providing theoretical support for the efficient extraction and large-scale production of giant salamander protein peptides.

Abstract:4,669 rural tourism resource points from the Official Catalogue of Rural Tourism Development Resources in Guangdong Province(First Batch)—published on the official website of Guangdong Provincial Department of Culture and Tourism—were selected as the research objects.By means of ArcGIS software,the spatial imbalance index and spatial agglomeration index of these rural tourism resources were calculated;additionally,the resources were superimposed with landform types and transportation lines for spatial correlation analysis.Based on the above exploration,the spatial distribution pattern characteristics,influencing factors,and optimization strategies of rural tourism resources in Guangdong Province were examined,thus providing scientific and reasonable suggestions for the sustainable development of rural tourism in the province.

Abstract:High power variable frequency motors commonly suffer from shaft current damage,which drastically accelerates bearings'the fatigue wear process and leads to premature bearing failure.The formation mechanism of this failure mode is complex and difficult to quantify.This article firstly analyzes the surface morphology characteristics of the rough scratch width and depth of the raceway and ball of ordinary/insulated bearings under the failure of shaft current damage,then studies the influence mechanism of working conditions on the inner and outer ring shaft current damage of bearings,and meanwhile deduces the fatigue wear evolution process of bearings under shaft current damage over time.The degree of damage caused by shaft current is ranked as follows:ordinary bearing inner raceway load area>ordinary bearing outer raceway non load area>ordinary bearing outer raceway load area>ordinary bearing outer raceway non load area>insulated bearing inner raceway>insulated bearing outer raceway load area>insulated bearing outer raceway non load area.

Abstract:Erythropoietin(EPO),a critical endogenous glycoprotein hormone,is widely used in the treatment of anemia.In recent years,studies have revealed that EPO not only plays a role in erythropoiesis but also exerts various other biological functions.Pharmacological research indicates that EPO has potential effects in protecting neurons and cardiomyocytes,alleviating inflammation,and maintaining intestinal barrier integrity.Furthermore,clinical researches on EPO's protective roles in renal,neurological,and cardiovascular health have been increasing.These studies highlight EPO's pharmacological actions beyond erythropoiesis and its progress in disease treatment,providing theoretical support and insights for its clinical application in diverse diseases.

Abstract:Taking Shenfu New City as the research object,a comprehensive evaluation model of urbanisation was established based on a four-dimensional framework(population,economy,space and society).The PSR(Pressure-State-Response)model was introduced to construct the water ecology assessment index system,and the dual system responsiveness and coordination model was set up.Analysis results indicated that from 2000 to 2014,the regional urbanisation index showed a significant upward trend,while the water ecological quality underwent a"U-shaped"evolution,initially decreasing and then increasing.The co-ordination model revealed that the systemic relationship changed from extreme imbalance to co-ordinated development,reflecting the effectiveness of environmental policy regulation.The impact of the urbanization process on water ecology exhibited a threshold effect:once the critical point of environmental carrying capacity is breached,ecological degradation trends can be reversed through investments in environmental governance.

Abstract:The enhancement effect on the performance of recycled pervious pavement concrete was studied through the repair of aggregates based on Microbial Induced Carbonate Precipitation(MICP)technology.The effects of recycled aggregate content and water-binder ratio on the compressive strength,splitting tensile strength and connected porosity of recycled pervious concrete were explored.Additionally,the improvement mechanism of recycled pervious pavement concrete performance through MICP technology was revealed by combining microscopic data such as nanoindentation hardness and elastic modulus of the recycled aggregate-cement paste interface region.Results indicate that the greater the recycled aggregate content,the stronger the enhancement effect of MICP.When the content of recycled aggregate is 20％and 50％,the splitting tensile strength of pervious concrete reached 1.96 MPa and 1.24 MPa,respectively,representing increases of 8.29％and 42.53％compared to pre-enhancement levels.Moreover,the mechanical properties of pervious concrete exhibit a trend of first decreasing and then increasing with an increase in the water-binder ratio.Once the water-to-binder ratio exceeds the flowability threshold,sedimentation and segregation of the paste were observed,negatively affecting the distribution of the connected porosity.Furthermore,MICP technology is found to effectively fill the original microcracks and pores of recycled aggregates,and enhance the microscopic mechanical properties of the recycled aggregate-cement paste interface area,which has a positive impact on the macroscopic performance of recycled pervious concrete.

Abstract:Against the macro background of rural revitalization,this paper addresses the shortcomings in the implementation of ideological and political education(IPE)in practical courses at universities,such as content monotony,low student participation,and insufficient integration with actual rural needs.This paper presents a practice of teaching reform taking the course of"Computer 2D Animation Production"as a case study.In response to the challenges in teaching,this study proposes a teaching reform practice plan of"one core guidance,dual chain integration,and five simultaneous measures".This plan effectively achieves the deep integration of IPE with professional knowledge teaching,as well as the close connection between course-competition integration and rural revitalization project practice,yielding remarkable results.This practice not only provides new ideas for the reform of IPE in universities but also lays a solid foundation for cultivating high-quality talents with the ability to serve rural revitalization.

Abstract:Objective To explore the impact of the teach-back health education model based on the WeChat platform on the psychological burden,oral health and quality of life of orthodontic patients.Methods One hundred orthodontic patients were enrolled between January 2023 and June 2024 and randomly divided into a control group and an observation group,which received routine care and a Teach-back health education model based on the WeChat platform,respectively.The psychological burden,oral health and quality of life of two groups of patients were compared.Results After nursing,the Hamilton Anxiety Scale(HAMA)and the Hamilton Depression Scale(HAMD)scores of the control group and observation group were significantly lower than those before nursing,and the difference was statistically significant(P＜0.001);The observation group had lower HAMA and HAMD scores than the control group,and the difference was statistically significant(P＜0.001).After nursing,the levels of gingival index(GI)and plaque index(PLI)in the control group and observation group were significantly reduced compared to the scores before nursing,and the difference was statistically significant(P＜0.001).The observation group had lower levels of GI and PLI than the control group,and the difference was statistically significant(P＜0.001).After nursing,the scores of the Quality of Life Short Form(QOL-BREF)of both the control group and the observation group were significantly improved compared to the scores before nursing,and the difference was statistically significant(P＜0.001).The observation group had higher scores in all aspects than the control group,and the difference was statistically significant(P＜0.001).Conclusion The teach-back health education model based on WeChat platform has significant application effects in orthodontic patients,which can reduce negative psychology,promote oral health and improve quality of life.

Abstract:This study applies the O-AMAS teaching model to the course"Food Processing Technology",using food low-temperature preservation as an example to design a systematic classroom teaching plan.Through the planning of case introduction,diversified learning activities,and effective assessment,the study aims to enhance students' understanding and application of low-temperature preservation technology.This teaching design improves teaching outcomes to some extent,providing some reference for cultivating innovative talents needed in the modern food industry.

Abstract:The competitive bidding sales behavior of general agricultural products and green agricultural products under the overconfident behavior of retailers being considered,an agricultural product supply chain with joint decision-making of suppliers and retailers was constructed,and the complexity characteristics of the pricing system were analyzed by using chaotic dynamics.The results show that both an overly rapid price adjustment speed and market disturbances are not conducive to the stability of the supply chain system.At this time,the supply chain system will be in a chaotic state more quickly.However,the increase of the cross-influence coefficient is beneficial to the expansion of the stability domain of the system.For the agricultural product supply chain system,government intervention and the autonomous learning behavior of enterprises can effectively alleviate the chaotic state of the agricultural product supply chain system.Furthermore,retailers' confident preference for the market will also keep the agricultural product supply chain system stable.

Abstract:To investigate the occurrence and development mechanisms of seepage failure in gradation-deficient sandy soil,a numerical seepage model based on CFD-DEM was established.Numerical experiments were conducted on gradation-deficient sandy soil with different combinations of fine particle content and seepage velocity to analyze changes in the seepage zones,seepage paths,and contact force chain.The results indicate that at the initial stage of seepage,fine particles begin to rotate and undergo slight displacement;as the permeability force increases,fine particles migrate in a clustering manner;in the later stage of seepage failure,fine particles travel through pores from upstream to downstream,resulting in a hollowed-out state of the soil.Properly increasing the fine particle content can reduce the risk of seepage failure,enhance the continuity of the contact force chain,but excessive fine particle content can lead to over-accumulation,causing downstream blockage.Seepage velocity also affects the migration path of fine particles.Under low flow velocity conditions,fine particles mainly migrate along the seepage channels in the middle area,while at higher flow velocities,fine particles first diffuse to the sides and then move along the middle seepage channels.

Abstract:In this study,two MOFs materials(SNNU-505-Zn and SNNU-505-Co)were synthesized,and their crystallinity,purity,thermal stability,pore structure,specific surface area,and adsorption separation performance for C6 alkane isomers were investigated.The results indicate that the specific surface areas of SNNU-505-Zn and SNNU-505-Co,measured using CO2 as a probe molecule at 195 K,were 199.71 m2/g and 52.768 m2/g,respectively.At 298 K and 10 kPa,the adsorption capacities of SNNU-505-Zn and SNNU-505-Co for n-hexane were 71.75 mg/g and 49.79 mg/g,while those for 3-methylpentane(3MP)were 37.99 mg/g and 40.78 mg/g,respectively.The adsorption selectivities of SNNU-505-Zn and SNNU-505-Co for nHEX/3MP at 298 K and 10 kPa were 46.63 and 1.71,respectively.Notably,SNNU-505-Zn exhibited higher selectivity for nHEX/3MP compared to most other adsorbents.

Abstract:Based on the limited rational decision-making of enterprises,this paper constructs a dynamic duopoly game model,taking into account the differences in consumers' willingness to pay for two brands.The brand perception parameter is introduced to study the dynamic evolution of enterprise games and explore the impact of changes in decision variables and exogenous variable parameters on model evolution.This paper conducts numerical simulations on the model and analyzes them with bifurcation diagrams,attractor graphs,and average profit graphs.Finally,by the delayed feedback control method,the chaotic state of the system was successfully controlled,and the market order can be stabilized.The research results show that excessively frequent price adjustments may lead to the system gradually falling into chaos.Brand perception is a comprehensive reflection of consumers' cognitive level regarding specific brand image,reputation,and conveyed values,playing an important role in corporate market competition.By the delayed feedback control method,it is possible to effectively guide chaotic states in price game models towards equilibrium points.

Abstract:Although the number of agreements continues to grow,their coverage expands,and their effectiveness gradually becomes evident,the cooperation between sister schools in Guangdong,Hong Kong,and Macau is facing challenges such as being limited to the level of"exchange and interaction",single form and content,and lack of deep integration.Clarifying the influencing factors can promote cooperation between sister schools in Guangdong,Hong Kong,and Macao,as well as between school organizations in general.From the perspective of organizational networks,this study summarizes eight influencing factor variables from three dimensions,and explores the impact of different variables on the effectiveness of sister school cooperation through survey.On this basis,suggestions are proposed to enhance the effectiveness of cooperation between sister schools in Guangdong,Hong Kong,and Macao.

Abstract:In order to understand the prevalence of FCoV in Guangdong,a total of 301 cat feces samples were collected from 6 cities in Guangdong from 2022 to 2023.FCoV identification and serotyping of the samples were performed by real-time fluorescent RT-PCR,and the infection of FCoV in cats was analyzed from age,gender,species and other aspects.The results showed that the positive rate of FCoV was(107/301),and the serotyping was type Ⅰ.The 55 S1 gene sequences are analyzed for genetic evolution with other reference strains at home and abroad.It was found that FCoV has a high degree of genetic diversity.

Abstract:To address the compatibility issues of starch-based hot melt adhesives,potato starch was selected as the main research subject.Ammonium persulfate was used as the initiator,and sorbic acid,stearic acid,lauric acid,and alginate were chosen respectively as graft monomers.Through esterification reactions,the potato starch was grafted and modified to produce modified potato starch.Subsequently,components such as ethylene-vinyl acetate copolymer(EVA)and rosin resin were added,and the mixture was melt-blended at specific temperatures to ultimately produce a biodegradable starch-based hot melt adhesive.Compared to the original potato starch,the modified starch showed better dispersibility in the adhesive,with uniform distribution,and without significant presence of granules.Performance tests indicated that the compatibility of the modified potato starch hot melt adhesive was improved compared to the original potato starch hot melt adhesive,with key performance indicators such as melt viscosity,softening point,hardness,elongation at break,and tensile strength meeting the national standards for hot melt adhesives used in food packaging.The experimental results demonstrate that the challenge of low compatibility of potato starch in hot melt adhesive preparation can be overcome,which enables the development of a modified potato starch hot melt adhesive that meets conventional market demands.

Abstract:It is of great significance in industry and value in economy to use adsorption separation technology to recover low-concentration C2H6 component from natural gas.The development of porous adsorbents with high performance is one of the critical challenges for promoting this technology.In this work,the synthesis of a microporous metal-organic framework,NU-2200,and its separation performance for C2H6/CH4 were reported.Synthesized hydrothermally,NU-2200 showed high crystallinity and thermal stability,with intact skeleton up to 550℃.Due to the confinement effect in micropores,NU-2200 exhibited a strong adsorption affinity towards C2H6 molecules with high adsorption heat of 35 kJ·mol-1.At 298 K,the adsorption capacity ofC2H6reached 1.89 mmol·g-1 and the IAST selectivity of C2H6/CH4 binary mixture was calculated as 17,demonstrating that NU-2200 showed a good prospect for the application on recovering low-concentration C2H6 components in natural gas.