Infrared emission spectra of in vivo human skin

Zusammenfassung Es wird ein Instrument auf Basis der Interferenzmethode, das häufig wiederholte IR-Spektren summieren kann, entwickelt und zur Spektralbeobachtung der IR-Emission der menschlichen Haut benützt.     

A bacterial dynamin-like protein

Dynamins form a superfamily of large mechano-chemical GTPases that includes the classical dynamins and dynamin-like proteins (DLPs). They are found throughout the Eukarya, functioning in core cellular processes such as endocytosis and organelle division. Many bacteria are predicted by sequence to possess large GTPases with the same multidomain architecture that is found in DLPs. Mechanistic dissection of dynamin family members has been impeded by a lack of high-resolution structural data currently restricted to the GTPase and pleckstrin homology domains, and the dynamin-related human guanylate-binding protein. Here we present the crystal structure of a cyanobacterial DLP in both nucleotide-free and GDP-associated conformation. The bacterial DLP shows dynamin-like qualities, such as helical self-assembly and tubulation of a lipid bilayer. In vivo, it localizes to the membrane in a manner reminiscent of FZL, a chloroplast-specific dynamin-related protein with which it shares sequence similarity. Our results provide structural and mechanistic insight that may be relevant across the dynamin superfamily. Concurrently, we show compelling similarity between a cyanobacterial and chloroplast DLP that, given the endosymbiotic ancestry of chloroplasts, questions the evolutionary origins of dynamins.     

Bionic asymmetry: from amiiform fish to undulating robotic fins

Similar to bionic non-smooth which has been successfully applied in anti-resistance and anti-adhesion, bionic asymmetry is also an inherent property of biological systems and is worth exploring for conceivable pragmatic applications. Therefore, bionic asymmetry for undulations is of main interest in this paper. We initially investigate bionic asymmetry with a case study of the undulating robotic fin, RoboGnilos, which evolved from the long dorsal fin of Gymnarchus niloticus in the amiiform mode. Since the performance of the pre-existing undulating fins is hardly satisfactory, we obtain bionic inspirations of undulatory asymmetry through observations and measurements on the specimen of G. niloticus, to improve upon the performance. Consequently, the newly acquired innovation for bionic asymmetry is incorporated into the previously derived kinematics model, and also applied to the experimental prototype. Both computational and experimental results verify that bionic asymmetric undulation generates better propulsion performance (in terms of linear velocity and efficiency) than the traditional symmetric modes with the same undulatory parameters. Supported by the National Defense Fundamental Research Project of China (Grant No. D28200613) and National Natural Science Foundation of China (Grant No. 50405006)     

靶温对Ti注入H13钢表面强化机制的研究

给出了不同靶温下的Ti注入H13钢的抗磨损特性,并研究了不同靶温对强化机理的影响。注入时靶温为液氮冷却、150和400℃,注入能量和注量分别为180keV和3×10~(17)cm~(-2)。不同靶温下注入后,样品表面硬度不同。但均比未注入样品硬度有明显提高。抗磨损能力也有提高,从液氮靶温注入的1.75倍,150℃靶温的7.7倍到400℃靶温的11.2倍。硬度和抗磨损能力的提高程度取决于不同靶温下注入H13钢表面强化机理的差异。低温注入以位错强化和超过饱和强化为主,150和400℃注入TiC,Fe_2Ti等析出相明显增多,它们以析出相的弥散质点强化为主。     

离子注入金属饱和注量及浓度分布的计算和实验研究

Ti 注入钢的射程参数(1～1000keV)是用 TRIM87程序计算而得到的.考虑到高注量注入溅射效应的影响,利用 Schuilz 模型计算了 Ti 注入钢和 Al 中浓度分布.对此模型中饱和注量与离子射程的关系提出了修正.给出了表面浓度与射程关系表示式.为了提高注入效率,节省注入时间,利用这些修正式能方便地给出饱和注量和注入元素浓度分布.计算结果与低温下注入的实验结果相符合,而与加温(400℃)注入的实验结果偏离较大.也考虑了注入合金择优溅射和注入效率的问题.     

Immunization of female rabbits against testosterone stimulates testosterone accumulation by isolated ovarian follicles

Ovarian follicles isolated from female rabbits after active immunization against testosterone-3-oxime bovine serum albumin produced more testosterone than similar follicles from controls.     

(滚)法推拿形成运动狭窄粘弹性血管血液动力学

建立具有局部轴向运动狭窄的粘弹性血管中脉动血流模型,模拟研究中医扌衮法推拿的血液动力学机理.血液为牛顿流体,血流遵循线化Navier Stokes方程,血管壁为线性粘弹体,扌衮法推拿作用下血管形成轴向运动狭窄水平外力作用.求解得出血管内血液流速、流量以及管壁切应力.结果表明在扌衮法作用下,血管一个心动周期血液流量有明显变化,且随手法频率的加快以及作用力水平渗透系数增大而增大,随最大狭窄度的增大而减小;同时狭窄段内以及狭窄后部切应力随手法作用也明显变化.手法频率,血管最大狭窄度和作用力水平渗透系数,是中医扌衮法推拿的重要参数.