整复手法对骶髂关节错位骨盆及下肢生物力学的影响

目的:观察骶髂关节错位患者在整复手法复位后腰背肌肌张力和对称性,骨盆、下肢生物力学的变化。方法:选取2022年5月至2023年3月期间就诊于福建中医药大学附属第二人民医院的骶髂关节错位患者120例,先理筋手法,再行整复手法,前错位60例,采用屈髋屈膝复位法,后错位60例,采用后伸扳法,隔日治疗1次,共治疗7次。对比治疗前后VAS评分、后表链肌张力K值、后表链肌张力对称值、骨盆倾斜、扭转、水平旋转情况,以及下肢支撑相、摆动相、足偏角的变化。结果:治疗后,骶髂关节前、后错位患者的VAS评分,后表链肌张力系数K值、肌张力对称性差值均较治疗前降低(P<0.05);治疗后,骶髂关节前、后错位患者的骨盆的倾斜、扭转、水平旋转角度均较治疗前减小(P<0.05);治疗后,骶髂关节前、后错位患者的步态周期中的支撑相较治疗前延长(P<0.05),摆动相较治疗前缩短(P<0.05),骶髂关节前错位患者较治疗前足偏角变大(P<0.05),后错位患者足偏角较治疗前变小(P<0.05)。结论:整复手法可以降低骶髂关节错位患者腰背肌肌张力,使两侧腰背肌趋于平衡,且能纠正骨盆的偏歪,改善下肢步态。

基于结构拓扑优化的股骨近端生物力线特征研究

骨折治疗常采用内固定法。为实现骨折的解剖复位和有效固定,内固定件的放置应顺应骨的生物力线,并适应骨皮质厚薄的特定解剖形态特征。为了探究人体骨骼生物力线和皮质厚薄分布特征及形成规律,本文以股骨近端为研究对象,应用三维重建技术建立三维模型;并以人类常见的单腿站立、外展和内收三种行为动作为工况,通过有限元分析得到股骨近端的生理应力分布情况。然后,本文运用结构拓扑优化方法模拟股骨近端在三种行为动作的综合作用下皮质厚薄的结构形态;并通过对比股骨近端解剖形态特征,分析股骨近端生物力线分布走向和骨皮质厚薄的特征及形成规律。研究结果表明,骨骼结构的生物力线和皮质厚薄形态特征及形成规律取决于人类活动时承受的载荷,生物力线的分布走向与骨生理承载时骨小梁排向和骨皮质纹路走向及坚实程度有关。本文提出的分析手段为确定骨骼的生物力线与皮质厚薄分布特征提供了一种解决方案,得出的结论或可指导骨折内固定件的合理放置。

步态周期下髋臼生物力学特征

目的 研究正常步态周期下髋臼周围区域应力分布规律,并进一步探究髋臼各柱的生物力线和骨皮质厚薄形态分布。方法 通过人体逆向动力学分析获取人体步态周期8个典型阶段的肌肉及髋关节载荷,应用三维重建技术构建髋关节三维模型,以所得载荷作为加载边界条件进行有限元分析及拓扑优化。结果 步态周期支撑相下髋关节载荷较大,中柱应变能占总应变能55%~69%,髋臼顶部应力较大;摆动相下髋关节载荷减小,中柱应变能所占百分比减小。髋关节不同的运动角度影响肌肉力,进而影响髋关节上应力分布规律。所获得髋臼各柱的生物力线分布与解剖学所提出的生物力线及骨小梁排布基本吻合,与拓扑优化结果中骨皮质较厚区域相对应。结论 通过数值模拟方法可以确定髋臼各柱的生物力线和骨皮质厚薄形态分布,为骨折治疗内固定装置的合理放置提供理论指导。

股骨近端骨纤维结构不良伴髋内翻畸形的髓内固定疗效

背景:股骨近端骨纤维结构不良伴髋内翻畸形必须进行外科矫形治疗,尽量恢复股骨正常的生物力线。目前尽管截骨矫形方案很多,但楔形外翻截骨已成主流,矫形后单纯外固定并发症较多,螺钉、钉-板系统等髓外固定存在问题较多,难以获得长期稳定的治疗效果,有研究表明,股骨近端处楔形外翻截骨、交锁髓内针内固定可获得较好的中长期治疗效果。目的:观察股骨近端骨纤维结构不良伴髋内翻畸形的髓内固定的治疗方法及生物相容性。方法:纳入23例股骨近端髋内翻伴肢体短缩畸形的股骨近端骨纤维结构不良患者,颈干角为56°-110°,平均79°,股骨相对长度较对侧短缩1.9-8.9cm,平均4.0cm。所有患者均行股骨近端处楔形外翻截骨、病灶清除、取肋骨植骨、交锁髓内钉内固定。结果与结论:固定后19例获得随访,随访时间6个月至2年,平均1年。所有内固定物均牢靠。股骨生物力线均基本矫正,截骨面处达骨性愈合,髋内翻畸形的颈干角矫正为90°-125°,平均112°,股骨相对长度矫正后较固定前延长1.5-2.5cm,平均2.0cm,所有患者髋关节功能影响不明显。固定后19例患者中3例正常行走无跛行,7例扶双拐行走,5例扶单拐行走,4例不扶拐轻度跛行。固定后19例患者中12例疼痛消失,6例疼痛明显缓解,加重并出现新疼痛1例。所有患者固定后均无感染、再骨折及畸形进展。结果证实,股骨近端处楔形外翻截骨、病灶清除、取肋骨植骨、交锁髓内钉内固定治疗股骨近端髋内翻伴肢体短缩畸形的股骨近端骨纤维结构不良效果良好,不仅可减少植骨量、充分矫正畸形及预防复发,而且中期随访观察证实截骨面处达到骨性愈合,髋关节功能改善良好,生物相容性较好。

Determination on Biological Characteristics of Nematode Rhabditis(Oscheius)sp.

[ Objective] The study was aimed to determine the biological characteristics of Rhabditis （Oscheius） sp. isolated from a rhizosphere soil of alfalfa field in Hailar City, Hulunbuir League, Inner Mongolia Autonomous Region. [ Method] The last instar larvae of Galleria mellonella and Tenebrio molitor were used as insect hosts. The infectivity of nematode was determined, and its heat tolerance ability was measured by using water bath method. [Result] The infectivity of the nematodes was lower at the dosages of 10, 20 and 40 IJs/larva, but higher at the dosages of 80,160, 32.0 and 640 IJs/larva. The corrected mortality （CM） of G. mellonella at 96 h and T. molitor at 120 h were both above 90%. The nematode infectivity was highest at the dosage of 80 IJs/larva when the hosts＇ CM reached 100% after 120 h. About 25% nematode individuals could survive in 36℃ water bath for 2 d in the densities of 1 000 -5 000 IJ/ml, after 6 d, there were still 3% -9% individuals survived, until 9 d the nematodes died totally. A hundred percent of the nematode individuals died in 38℃ and 40 ~C water bath after 6 h and 2 h, respectively. [Conclusion] Rhabditis （ O. ） sp. has a higher potential to cause the host mortality and represents heat tolerance up to 36℃.

Adsorption of Cu^(2+), Zn^(2+) and Cd^(2+) on Bacillus subtilis

A process of biosorption of Cu^2＋, Zn^2＋ and Cd^2＋ on Bacillus subtilis was investigated. The experiments show that the process of biosorption is quite fast, The maximum adsorption was reached after 5 min and hardly changed with time. The experimental data was analyzed using four sorption kinetic models： the pseudo-first-order, the Ritchie second-order, the modified second-order and the Elovich equations, which helped to determine the best-fit equation for the sorption of metal ions onto biomass, The results show that both the Ritchie second-order and modified secondorder equations can fit the experimental data. The Langmuir model is able to accurately describe adsorption of Cu^2＋ and Zn^2＋ on B. subtilis. The experimental data points of adsorption Cd^2＋ and Zn^2＋ on B. subtilis are described by Freundlich isotherms model.

Can coordination variability identify performance factors and skill level in competitive sport? The case of race walking

Background:Marginal changes in the execution of competitive sports movements can represent a significant change for performance success.However,such differences may emerge only at certain execution intensities and are not easily detectable through conventional biomechanical techniques.This study aimed to investigate if and how competition standard and progression speed affect race walking kinematics from both a conventional and a coordination variability perspective.Methods:Fifteen experienced athletes divided into three groups(elite,international,and national) were studied while race walking on a treadmill at two different speeds(12.0 and 15.5 km/h).Basic gait parameters,the angular displacement of the pelvis and lower limbs,and the variability in continuous relative phase between six different joint couplings were analyzed.Results:Most of the spatio-temporal,kinematic,and coordination variability measures proved sensitive to the change in speed.Conversely,non-linear dynamics measures highlighted differences between athletes of different competition standard when conventional analytical tools were not able to discriminate between different skill levels.Continuous relative phase variability was higher for national level athletes than international and elite in two couplings(pelvis obliquity—hip flex/extension and pelvis rotation—ankle dorsi/plantarflexion) and gait phases(early stance for the first coupling,propulsive phase for the second) that are deemed fundamental for correct technique and performance.Conclusion:Measures of coordination variability showed to be a more sensitive tool for the fine detection of skill-dependent factors in competitive race walking,and showed good potential for being integrated in the assessment and monitoring of sports motor abilities.

Interaction between Dairy Yeasts and Lactobacillus rhamnosus GG in Milk

The presence of Geotrichum candidum in fresh cheese is considered to be a contaminant and may lead to the product spoilage. The oxidative yeast Candida maltosa firstly isolated from the spoiled fruit yoghurt surface in Slovakia belongs to the yeast contaminants of fermented dairy products. The effect of the cultivation temperature and the presence of Lactobacillus rhamnosus GG on the growth of dairy spoilage yeasts in ultrapasteurized milk was studied. Addition of Lb. rhamnosus GG in milk caused partial inhibition of the yeast growth dynamics in milk. The water activity transformation of Gibson model after the temperature modification （Tw） was applied to model growth dynamics of G. candidum in pure and mixed culture, respectively： In μ_Gc=-5.0376＋2.7281 Tw-0.4217Tw^2, lnμ_CC_LGG=-6.0033＋3.2996Tw-0.5553Tw^2. The effect of different Lb. rhamnosus GG addition and the incubation temperature on the C. maltosa growth dynamics was analyzed by linear regression methodology and described by using following equations： lnGr1=-5.3674＋0.2341T＋0.2599N0-0.0032T^2-0.0492N0^2-0.0068TN0 and lnGr11=-9.5457-0.249T＋2.3823N0 ＋0.0099T^2-0.2324N0^2＋0.0098TN0 Based on the principles of predictive microbiology, the mutual microbial interactions and potential application of the lactobacillus strains in food protection are discussed.

Experimental Study on Stress Relaxation and Creep Properties of Human Thoracolumbar Vertebral Bodies and Intervertebral Discs

Objective:Underwater shock can produce extremely high accelerations, resulting in severe human injuries on shipboard, and human thoraco lumbar spines are prone to suffer from injuries by ship shock motion. To observe the viscoelasticity of thoracolumbar of young fresh cadavers, and to provide biomechanical parameters for both research and clinical practice. Materials and Methods:5 fresh young male cadavers (aged 22 to 31 years) were provided, and 15 thoracolumbar spinal anatomies of 5 samples were harvested within 1 hour of death. WE-10A universal testing machine was used for creep and relaxation tests.Results:Stress relaxation and creep deformation equations are derived from the biomechanics model and the measured and simulated curves are compared. The creep in vertebral bodies and intervertebral discs exhibited significantly changes in the first 5 min and 10 min, respectively. The stress rapidly decreased in the first 2 min, and then gradually went balance during the relaxation process. Conclusion:The change in creep rate is significant at early stage,and gradually slows down.This indicates that the differences between internal pressure and local pressure are decreased until balance. The simulated curve derived from equation coincides with the experimental data to a large degree, which states that the equation is rational and reliable.

从筋膜连续性探讨经筋实质

近年来经筋基础研究有“从虚向实”转变的趋势,说明经筋基础研究有望成为经络研究的突破点。经筋是经络中少有的“更符合解剖实体”的一种概念,其解剖实质有多种学说。文章通过对经筋、筋膜的基本概念框定,阐述“束骨而利机关”与筋膜框架性结构,“为刚为墙”与筋膜整体纤维网络结构,“反映病候”与筋膜组织特性,“调经脉”与筋膜、力的关系,认为筋膜基本实现经筋的四大功能,以便学术界更好开展基于解剖学、组织学、病理学、生物力学、影像学、工程学等的经筋基础研究。

The effects of cues from kingsnakes on the reproductive effort of house mice

It is not clear if rodents express inducible defenses in response to reptilian predators such as snakes. We tested the hypothesis that adult house mice Mus musculus decrease aspects of their reproductive effort upon 1 hour of exposure every 48 hours for a 25-day period to the fecal material and shed skins of a euryphagous ophidian predator, the kingsnake Lampropeltis getula, that had been fed mice. We found no significant differences in the total number of offspring born, the number of pups per litter, and the mean weight of pups in litters born to male and female mice that were exposed to predator cues and those mice that were not exposed to such cues. The lack of an inducible response may be associated with the low cost of an effective defense, or the lack of an effective defense against a generalist snake predator [Current Zoology 59 （1）： 135-141, 2013].

Biomechanical researches on tissue engineering bone constructed by deproteinated bone

Objective： To study biomechanical changes of newly formed bones 24 weeks after repairing large defects of long bones of goats using heterogeneous deproteinated bone （DPB） prepared by modified methods as an engineering scaffold. Methods： According to a fully randomized design, 18 goats were evenly divided into three groups： normal bone control group （Group A）, autologous bone group （Group B） and experimental group （Group C）. Each goat in Groups B and C were subjected to the periosteum and bone defect at middle-lower part of the right tibia （20% of the whole tibia in length）, followed by autologous bone or DPB plus autolognus MSCs ＋ rhBMP2 implantation, respectively and semi- ring slot fixation; while goats in Group A did not perform osteotomy. At 24 weeks after surgery, biomechanical tests were carried out on the tibias. Results： At 24 weeks after surgery, the results of anticompression test on tibias in three groups were recorded by a functional recorder presented as linear pressure-deformation curve. The shapes of the curves and their change tendency were similar among three groups. The ultimate pressure values were 10.74 MPa±1.23 MPa, 10. 11 MPa±1.35 MPa and 10.22 MPa±1.32 MPa and fracture compression rates were 26.82%±0.87%, 27.17%±0.75% and 28.22%±1.12% in Groups A, B and C, respectively. Comparisons of anti-compression ultimate pressures and fracture compression rates among three groups demonstrated no significant difference （PAB=0.415, PBC=0.494）. Three-point antibend test on tibias was recorded as load-deformation curves, and the shapes of the curves and their change tendency were similar among three groups. The ultimate pressure values of the anti-bend test were 481.52 N±12.45 N, 478.34 N±14.68 N and 475.62 N±13.41 N and the fracture bend rates were 2.62 mm±0.12 mm, 2.61 mm±0.15 mm and 2.81 mm±0.13 mm in Groups A, B and C, respectively. There was no significant difference between groups （PAB=0.7, PBc=0.448）. The ultimate anti-torsion torque values were 6.55 N.mi-0.25 N.m, 6.34 N＇m^0.18 N＇m and 6.42 N＇m^0.21 N＇m and fracture torsion rates were 29.51°±1.64°, 28.88±1.46° and 28.81°±1.33° in Groups A, B and C, respectively. There was no significant difference between groups （PAB=0.123, PBc=0.346）. Conclusions： The biomechanical characteristics of newly formed bones from heterogeneous DPB for repairing large segmental long bone defect are comparable to those of normal bones and autologous bones. DPB has the potential for clinical usage as bone graft material.

Biomathematical analysis of carbon nanotubes due to ciliary motion

In this paper, the consequences of cilia motion are reflected by the CNTs nanoparticles. The problem is expressed in a symmetric channel with ciliated walls. Exact solutions of the governing flow problem are obtained for pressure gradient, temperature and velocities of the fluid. Streamlines for the velocity profile are plotted to discuss the trapping phenomenon.

The heart rate - breathing rate relationship in aquatic mammals： A comparative analysis with terrestrial species

Aquatic and semi-aquatic mammals, while resting at the water surface or ashore, breathe with a low frequency （f） by comparison to terrestrial mammals of the same body size, the difference increasing the larger the species. Among various interpretations, it was suggested that the low-f breathing is a consequence of the end-inspiratory breath-holding pattern adopted by aquatic mammals to favour buoyancy at the water surface, and evolved to be part of the genetic makeup. If this interpretation was correct it could be expected that, differently from f, the heart rate （HR, beats/min） of aquatic and semi-aquatic mammals at rest would not need to differ from that of terrestrial mammals and that their HR-fratio would be higher than in terrestrial species. Literature data for HR （beats/min） in mammals at rest were gathered for 56 terrestrial and 27 aquatic species. In aquatic mammals the allometric curve （HR=191 .M^18; M= body mass, kg） did not differ from that of terrestrial species （HR=212.M^-0.22） and their HR-fratio （on average 32±5） was much higher than in terrestrial species （5±1） （P〈0.0001）. The comparison of these HR allometric curves to those forfpreviously published indicated that the HR-fratio was body size-independent in terrestrial species while it increased significantly with M in aquatic species. The similarity in HR and differences in f between aquatic and terrestrial mammals agree with the possibility that the lowfof aquatic and semi-aquatic mammals may have evolved for a non-respiratory function, namely the regulation of buoyancy at the water surface [Current Zoology 61（4）： 569-577, 2015].

IMPULSIVE CONTROL IN MICROORGANISMS CONTINUOUS FERMENTATION

This work presents the nonlinear dynamical system of continuous fermentation from glycerol to 1,3-propanediol. The impulsive control scheme of continuous culture is intro- duced. By employing impulsive control, Lyapunov＇s method and comparison technique, sufficient conditions are established for the asymptotical stability and synchronization of the dynamical system of continuous fermentation. The upper bound of the impulse interval is also estimated. An example will illustrate the effectiveness of the results in Sec. 4.

MODELING AND PARAMETER IDENTIFICATION FOR MULTISTAGE SIMULATION OF MICROBIAL BIOCONVERSION IN BATCH CULTURE

The bioconversion of glycerol to 1,3-propanediol is a complex bioprocess. The item of product inhibition in the equation of Specific rate of cell growth is overlapped in [L. Wang, J. X. Ye, E. M. Feng and Z. L. Xiu, An improved model for multistage simula- tion of glycerol fermentation in batch culture and its parameter identification, Nonlinear Anal. Hybrid Syst. 3（4） （2009） 455462]. Therefore, in this work, the specific rate of cell growth is modified by the mechanism of multistage simulation of microbial bioconversion and the previous time-dependent model is converted to the autonomous standard form. The properties of the solutions for the nonlinear dynamic system are discussed and the identifiability of the parameters is proved. Finally the feasible optimization algorithm is constructed to find the optimal parameters for the system. Numerical result shows that the improved model with identified parameters can describe the batch culture better, compared with the previous results.