Alterations in Serum Lipids and Lipoproteins Induced by Neoadjuvant Chemotherapy in Patients with Osteosarcoma around the Knee Joint:A Retrospective Analysis

Objective To investigate the serum lipid profiles of patients with localized osteosarcoma around the knee joint before and after neoadjuvant chemotherapy.Methods After retrospectively screening the data of 742 patients between January 2007 and July 2020,50 patients aged 13 to 39 years with Enneking stage II disease were included in the study.Serum lipid levels,including total cholesterol(TC),triglycerides(TG),high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),lipoprotein-α[Lp(a)],and apolipoprotein A1,B,and E(ApoA1,ApoB,and ApoE),and clinicopathological characteristics were collected before and after neoadjuvant chemotherapy.Results The mean levels of TC,TG,and ApoB were significantly increased following neoadjuvant chemotherapy(16%,38%,and 20%,respectively,vs.pretreatment values;P<0.01).The mean levels of LDL-C and ApoE were also 19%and 16%higher,respectively(P<0.05).No correlation was found between the pretreatment lipid profile and the histologic response to chemotherapy.An increase in Lp(a)was strongly correlated with the Ki-67 index(R=0.31,P=0.023).Moreover,a trend toward longer disease-free survival(DFS)was observed in patients with decreased TG and increased LDL-C following chemotherapy,although this difference was not statistically significant(P=0.23 and P=0.24,respectively).Conclusion Significant elevations in serum lipids were observed after neoadjuvant chemotherapy in patients with localized osteosarcoma.There was no prognostic significance of pretreatment serum lipid levels on histologic response to neoadjuvant chemotherapy.The scale of increase in serum Lp(a)might have a potential prognostic role in osteosarcoma.Patients with increased LDL-C or reduced TG after chemotherapy seem to exhibit a trend toward favorable DFS.

Swarm Intelligence Research:From Bio-inspired Single-population Swarm Intelligence to Human-machine Hybrid Swarm Intelligence

Swarm intelligence has become a hot research field of artificial intelligence.Considering the importance of swarm intelli-gence for the future development of artificial intelligence,we discuss and analyze swarm intelligence from a broader and deeper perspect-ive.In a broader sense,we are talking about not only bio-inspired swarm intelligence,but also human-machine hybrid swarm intelli-gence.In a deeper sense,we discuss the research using a three-layer hierarchy:in the first layer,we divide the research of swarm intelli-gence into bio-inspired swarm intelligence and human-machine hybrid swarm intelligence;in the second layer,the bio-inspired swarm intelligence is divided into single-population swarm intelligence and multi-population swarm intelligence;and in the third layer,we re-view single-population,multi-population and human-machine hybrid models from different perspectives.Single-population swarm intel-ligence is inspired by biological intelligence.To further solve complex optimization problems,researchers have made preliminary explor-ations in multi-population swarm intelligence.However,it is difficult for bio-inspired swarm intelligence to realize dynamic cognitive in-telligent behavior that meets the needs of human cognition.Researchers have introduced human intelligence into computing systems and proposed human-machine hybrid swarm intelligence.In addition to single-population swarm intelligence,we thoroughly review multi-population and human-machine hybrid swarm intelligence in this paper.We also discuss the applications of swarm intelligence in optimization,big data analysis,unmanned systems and other fields.Finally,we discuss future research directions and key issues to be studied in swarm intelligence.

Regularization of mathematical model for chip flow angle catastrophe

The chip flow angle(CFA)catastrophe in double-edged cutting results in a significant reduction in the cutting force,which can benefit the applications.However,established potential functions(i.e.,cutting power calculation functions)of mathematical models for the CFA catastrophe are presented in the form of transcendental functions with two control parameters and one state parameter,which are extremely complex.A method is proposed herein to realize the regularization of the potential functions and establish mathematical models in a standard form and with complete content for the CFA catastrophe.Using this method,the potential function of the CFA catastrophe is expanded into a k-order Taylor polynomial at each midpoint of N end-to-end equally partitioned intervals of the state parameter using the Taylor function provided in MATLAB.The potential function after piecewise Taylor expansion is transformed into the same form as the potential function of the standard cusp catastrophe model by truncating the first five terms of the Taylor polynomial and eliminating the third-order term of the state parameter with elementary transformation.Hence,the regularization of potential function is realized.Subsequently,the regularization of equilibrium surface and bifurcation set can be realized based on the conclusions of the catastrophe theory.Regularization errors of the potential function,equilibrium surface,and bifurcation set are defined to evaluate the effectiveness of this regularization method.The problem of calculating regularization errors is regarded as an optimization problem.The‘‘simulannealbnd’’function provided in MATLAB is used to solve the problem.Applying the proposed method,the regularization of a mathematical model for the CFA catastrophe established by the predecessor is completed;a mathematical model(i.e.,standard cusp catastrophe model)in a standard form and with complete content for the CFA catastrophe is established;and the corresponding regularization errors are analyzed.The regularization errors of the potential function,equilibrium surface,and bifurcation set curves are 5.4855910-4%,0.3206%,and 4.6539%,respectively.Based on the equilibrium surface and the bifurcation set curves constructed using the regularized mathematical model for the CFA catastrophe,the mechanism of the CFA catastrophe and the specific approach to render the cutting system operable in a low-energy consumption state by controlling the historical change path of the control point are analyzed.This study will promote the rational use of the CFA catastrophe.