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BACKGROUND:The medial patellofemoral ligament reconstruction is the most commonly used method for the treatment of lateral dislocation of patella at present.The ultimate goal is to adjust the patella to the normal anatomical position and restore the patella track.Currently,the main core problem of medial patellofemoral ligament reconstruction is the selection of its femoral end fixation point. OBJECTIVE:Finite element method was used to analyze the limiting effect of the reconstructed medial patellofemoral ligament on the patella at different flexion angles of the knee joint,and to simulate the limiting effect of medial patellofemoral ligament reconstruction at different fixation points of the femoral end on the patellofemoral end,so as to provide help for the selection of fixation points of the femoral end during the reconstruction of the medial patellofemoral ligament. METHODS:A finite element model of knee including bone and soft tissue was established according to the extracted CT and MRI data of knee joint.When the knee flexion angle of 30° and 60° was simulated,the medial patellofemoral ligament was constructed by selecting different fixation points of femur end.The contact stress and contact area between patellofemoral joints at different points were compared,as well as the transverse binding force on patella.The equilength of the medial patellofemoral ligament constructed from the same fixation point of the femoral end at different flexion angles was verified to study the effect of various reconstruction positions of the medial patellofemoral ligament. RESULTS AND CONCLUSION:(1)A three-dimensional finite element model of the knee joint at 30° and 60° flexion angles was established to construct the medial patellofemoral ligament at different fixation points of the femur end.The medial patellofemoral ligament constructed at the same position of the femur end had usable isometric length at different flexion angles.(2)After the lateral displacement of the patella,in the transverse direction,the medial patellofemoral ligament constructed at different fixed points of the femur end produced different transverse binding force on the patella,and the transverse binding force was maximum at the anterior 10 mm and minimum at the proximal 5 mm.In the longitudinal direction,the location and size of stress concentration points on the patella cartilage were roughly the same,and the contact pressure did not change much.However,the contact area between the patella cartilage and the femoral cartilage was significantly different,with the maximum contact area at 10 mm at the front end and the minimum contact area at 5 mm at the proximal end.(3)The medial patellofemoral ligament constructed at the center of the saddle region has a good lateral restriction on the patella,but does not cause excessive restriction on the patella in the longitudinal restriction,and can achieve a good restriction on the patella.

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BACKGROUND:The injury of the anterior talofibular ligament is most common in joint ligament injuries.The use of the finite element method to simulate ankle joint motion has the advantages of short experimental time,complex boundary conditions that can be simulated,and mechanical properties. OBJECTIVE:To analyze the effect of the anterior talofibular ligament on the stress distribution of the talus trochlea and the stability of the ankle joint. METHODS:A finite element model of the ankle was established based on CT and MRI images of patients with anterior talofibular ligament injury who were followed up for two months after Brostr?m surgery to simulate ankle joint stress in patients with anterior talofibular ligament injury before and after surgery during normal gait cycles(ground phase,neutral phase,and off-ground phase).The stress distribution and maximum stress value of the talus bone cartilage were measured before and after surgery,and their differences were analyzed. RESULTS AND CONCLUSION:Under normal gait,the anterior talofibular ligament has a certain protective effect on the talus trochlea in any position,reducing the wear of the ankle joint on the talus trochlea during movement.In all three phases,stress concentration was observed on the surface of the talus trochlea near the inner side of the ankle joint.The influence of the anterior talofibular ligament on the stability of the talus trochlear is much greater in the off-ground phase than in the ground phase and neutral phase.Under certain circumstances,the greater the torque on the ankle joint,the more significant the effect of the anterior talofibular ligament on the stability of the talus trochlea.

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The concept of holographic law is widely reflected in the theory and clinical practice of traditional Chinese medicine （TCM）. From philosophical perspective， TCM encompasses rich holographic law concepts， such as the theory of qi as the fundamental essence， mutual rooting and mutual storage of yin and yang， and mutual storage and classifications of the five phases. Through philosophical exploration of holographic law in TCM， this paper aimed to elucidate the connection between holographic law and TCM， and analyze the value and limitations of holographic law in TCM. Future research on holographic law in TCM should not only philosophically scrutinize the relationship between the whole and its parts under the guidance of holographic law thinking， but also incorporate qualitative and quantitative studies by referring to modern disciplines such as anatomy， physiology， and pathology， in order to better understand and validate the holographic law concepts in TCM.

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OBJECTIVES: To determine whether water kurtosis and diffusional metrics derived from diffusional kurtosis imaging (DKI) within primary central nervous system lymphomas (PCNSLs) and high-grade gliomas (HGGs) correlate with cellularity and/or nuclear-to-cytoplasmic (N/C) ratio. METHODS: Forty-four and 43 pathologically confirmed high-grade glioma and primary central nervous system lymphoma specimens between May 2013 and November 2016 were retrospectively reviewed. Diffusional metrics, kurtosis metrics, cellularity, and N/C ratios in PCNSLs and HGGs were compared using the Mann-Whitney U test (significant level, p < 0.007 [0.05/7]); Bonferroni correction). RESULTS: Mean kurtosis (MK), axial kurtosis (K//), and radial kurtosis (K⊥) in PCNSLs were 0.857 (0.693-0.924), 0.837 (0.660-0.941), and 0.834 (0.685-0.937), respectively; and 0.629 (0.524-0.716), 0.575 (0.511-0.689), and 0.675 (0.532-0.766), respectively, in HGGs (all p < 0.001). No significant differences in fractional anisotropy (FA), mean diffusion (MD), axial diffusion (λ//), and radial diffusion (λ⊥) were found between HGGs and PCNSLs. Cellularity was higher in PCNSLs than in HGGs (p = 0.125); whereas, the N/C ratio in PCNSLs was significantly higher than that in HGGs (p < 0.001). All DKI metrics (FA, MD, λ//, λ⊥, MK, K//, and K⊥) were significantly correlated with N/C ratio in PCNSLs with correlation coefficients being rho = 0.418, - 0.722, - 0.525, - 0.768, 0.704, 0.579, and 0.686, respectively. Cellularity in PCNSLs and HGGs did not correlate with any kurtosis or diffusional metrics. CONCLUSIONS: Difference of kurtosis parameters between PCNSLs and HGGs is correlated with their diverse N/C ratio. KEY POINTS: • DKI has considerable value in differentiating between PCNSLs and HGGs. • DKI can provide important information on nuclear-to-cytoplasmic ratio. • Difference of kurtosis parameters between PCNSLs and HGGs correlated well with their diverse N/C ratios.

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Recently, projection neural network (PNN) was proposed for solving monotone variational inequalities (VIs) and related convex optimization problems. In this paper, considering the inertial term into first order PNNs, an inertial PNN (IPNN) is also proposed for solving VIs. Under certain conditions, the IPNN is proved to be stable, and can be applied to solve a broader class of constrained optimization problems related to VIs. Compared with existing neural networks (NNs), the presence of the inertial term allows us to overcome some drawbacks of many NNs, which are constructed based on the steepest descent method, and this model is more convenient for exploring different Karush-Kuhn-Tucker optimal solution for nonconvex optimization problems. Finally, simulation results on three numerical examples show the effectiveness and performance of the proposed NN.

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Objective To explore the risk factors of gestational diabetes mellitus and its influence on pregnancy outcome,and to provide guidance for early intervention of gestational diabetes to improve pregnancy outcome in clinic.Methods Totally 159 patients with gestational diabetes mellitus in our hospital from January 2014 to January 2016 as observation group were collected,and at the same time,634 healthy pregnancy women as control group were collected.The risk factors of gestational diabetes mellitus were analyzed by the Logistic regression analysis and comparison of pregnancy outcome between two groups was conducted.Results The patients in the observation group with age ≥ 35 years,overweight or obesity before pregnancy,adverse pregnancy history,family history of diabetes,hypertension and vaginal candida and thyroid peroxidase antibody (TPOAb) compared with the control group,the difference was statistically significant (P ＜ 0.05).Multivariate logistic regression analysis showed that age ≥ 35 years,overweight or obesity before pregnancy,adverse pregnancy history,family history of diabetes,and positive TPOAb were the independent risk factors of gestational diabetes mellitus,OR was 2.441,2.889,1.486,4.879,and 1.323,respectively;the difference was statistically significant (P ＜ 0.05).The incidence of premature rupture of membrane,pregnancy hypertensive disorder,premature birth,polyhydramnios,uterine-incision and postpartum hemorrhage in observation group were higher than those in control group,the difference was statistically significant (P ＜ 0.05).The incidence of giant baby,fetal distress and mild neonatal asphyxia were higher than those in control group,and the difference was statistically significant (P ＜ 0.05).No statistical significance in fetal growth restriction,neonatal malformations between two groups was found (P ＞ 0.05).Conclusions Age ≥35 years,overweight or obesity before pregnancy,adverse pregnancy history,family history of diabetes,and thyroid dysfunction were the independent risk factors of gestational diabetes mellitus,and it has serious effect on pregnancy outcome,so that it should take measures to prevent the independent risk factors.

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The inclusion compound of amylose and salicylic acid (SA) was prepared by a sealed temperature control method, and the formation of the inclusion compound was confirmed by IR spectrum and powder X-ray diffraction. The kinetic parameters of dissociation of amylose/SA compound were studied by the nonisothermal method which was defined as a relationship between the dissociation ratio and time. The values of activation energy (Ea) and frequency factors (InA) were calculated by a nonlinear least-square method. In this study, the formation of the inclusion compound of amylose/SA was confirmed by IR spectrum powder X-ray diffraction. SA existed in a molecule form in the spiral stouction of amylose. The dissociation of amylose/SA compound was attributed to first order reaction. The values of Ea calculated by the nor-isothermal method were 21.71 and 22.41 kJ x mol(-1) at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method value of Ea was 22.17 kJ x mol(-1); the calculated InA values were 9.32 and 10.08 at heating rate 5 and 10 degrees C x h(-1), respectively. The corresponding isothermal method lnA value was 9.26. The results were in good agreement with Ea values and lnA values by isothermal method. These results indicated that the non-isothermal method described in this study could be adequately used for the stability study of inclusion compound and was a rapid and accurate method for the determination of kinetic parameters.