潘婷强韧防掉发洗发露的Ames试验研究

目的应用Ames试验探讨潘婷强韧防掉发洗发露是否具有致突变性。方法采用组氨酸缺陷型鼠伤寒沙门氏菌TA97,TA98,TA100和TA102进行潘婷强韧防掉发洗发露微生物回复突变试验。结果在1.25~0.156mg/皿剂量范围内,在加S9mix和不加S9mix平行条件下测试,试验结果为阴性。结论潘婷强韧防掉发洗发露在本实验中未见致突变性。

海洋文化的科学思想发轫

海洋文化具有深刻的科学思想底蕴,海洋文化的科学思想发韧,重要的工作是:剖析和发扬海洋文化所显现的珍贵的科学思想价值;发掘海洋科学文化所蕴含的深刻的思想精粹;将科学文化的珍贵思想意蕴加以传承和弘扬。海洋的开发、利用和保护、关怀,这之间是有韧度和张力的,做好这一工作意义重大。

论辛亥革命对中国道路的发轫

辛亥革命推翻了清朝封建专制制度,建立了资产阶级民主共和国,在探索和开创中国道路上具有开拓性意义。它开启了中国道路的最初探索,为中国共产党开创中国特色社会主义道路奠定了基础、开辟了道路,对中国道路具有发轫作用,是探索中国道路发展的一个里程碑。

韵的显现与追求——晋代书风论要

晋代书法以“尚韵”为特征,但缺乏大气磅礴和雄浑之感。究其因,是由于他们限于对作为客体的物的反映,而忽视对作为主体的人的表现,同时,文字性居其主导地位,艺术性居其次。晋书“韵”的发韧与生成:一是晋书之法的宽松灵活;二是笔致的轻灵娟秀,流畅自然。晋代书论正是按照这样的推演逻辑,完成其书法艺术的本体思考的。

Development and Ultrastructure of the Phloem Ganglion in Bamboo Node

The development, cytological characters and ultrastructure of phloem ganglion in the nodal region of Phyllostachys edulis (Carr.) H. de Lehaie, a most economically important bamboo, were investigated and the possible physiological function of this special structure was proposed. The phloem ganglion derived directly from procambium is situated at the sites where the vascular bundle forks and is present in pairs. The phloem ganglion is spindle_like in appearance and usually consists of 4 to 6 layers. Two kinds of cells in the ganglion could be distinguished. In the middle, there are two layers of filiform cells with pointed ends so that there are no normal sieve plates. Nevertheless, there are many pits on the lateral wall of the filiform cells. The other type of cells located at both ends of the spindle which possess an intermediate form between the filiform cell and the normal sieve tube. The walls of these cells towards the filiform cells are strongly convex forming a special sieve plate. Ultrastructure study showed that cells in the ganglion are connected by enriched plasmodesma. During early differentiation, the paramural body and the ingrowth of cell wall could be observed. It indicates that the cells of phloem ganglion have the character of transfer cells. The organelles in the mature cells are mainly plastids with abundant accumulation of proteins of crystalline structure. The above_mentioned results suggest that the physiological function of the phloem ganglion is closely related with substance transport.

Effect of loading rate on fracture behaviors of shale under mode I loading

In this study,the effect of loading rate on shale fracture behaviors was investigated under dynamic and static loading conditions.Cracked straight through Brazilian disc(CSTBD)shale specimens were tested with a split Hopkinson pressure bar(SHPB)setup and INSTRON1346 servo-testing machine under pure mode I loading conditions.During the test,the crack propagation process was recorded by high-speed(HS)camera,and the acoustic emission(AE)signal generated by the fracture was collected by acoustic emission(AE)system.At the same time,crack propagation gauge(CPG)was used to measure the crack propagation velocity of the specimen.The results show that the crack propagation velocity and fracture toughness of shale have a positive correlation with the loading rate.The relationship among the crack propagation velocity,the fracture toughness and the loading rate is established under the static loading condition.In addition,the characteristics of AE signals with different loading rates are analyzed.It is found that the AE signals generated by microcrack growth decrease with the increase of loading rates.Meanwhile,the turning point of cumulative counting moves forward as the loading rate increases,which shows that the AE signal generated by shale fracture at low loading rate mainly comes from the initiation and propagation of microcracks,while at high loading rate it mainly comes from the formation of macro large-scale cracks.The fracture mechanism that causes shale fracture toughness and crack propagation velocity to vary with loading rate is also discussed based on the analysis results of AE signals.

Use of tightrope fixation in ankle syndesmotic injuries

Objective： Conventional fixation of syndesmotic injuries with screws remains problematic. A novel fibrewire device （Tightrope） has suggested advantages. However, small case series have reported high soft tissue complication rates. The purpose of our study was to quantify complication rates and further procedures in patients treated with Tightropes. A secondary objective was to determine incidence of complications and further procedures in those treated with syndesmotic screws over the same period. Methods： All patients undergoing syndesmotic fixa- tion for ankle fracture between May 2008 and October 2009 were retrospectively reviewed. Incidence of complications, secondary procedures, maintenance of syndesmotic reduc- tion and time spent on non-weight bearing were recorded. Family doctors were contacted for those treated with Tight- ropes to check for any complications managed elsewhere. Results： Thirty-five patients required syndesmoticfixation, in which 12 were treated with Tightropes. They were followed up in clinic for a mean of 12.4 weeks. Family doctors were contacted at mean 14.6 months after treatment to determine any complications suffered. There were no complications attributable to method of fixation. In this series, 12 patients underwent 13 procedures and no patient had recurrent diastasis at discharge; 23 patients treated with screw fixation underwent 45 procedures （19 were screw removals）. There was 1 case ofsyndesmotic diastasis. Screw removal resulted in 2 minor complications. Conclusion： Tightrope fixation provideds effective syndesmotic fixation that is maintained at discharge. We do not experience soft tissue complications reported elsewhere.

Brittle-Ductile Transition of Ferroelectric Ceramics Induced by Thermally Activated Dislocation Emission

Thermally activated dislocation emission in high-temperature ferroelectric ceramics is investigated through an assumption of thermal stability and a novel analytical method. The stress intensity factor (SIF) arising from domain switching is evaluated by using a Green's function method, and the critical applied electric field intensity factor (CAEFIF) for brittle fracture at room temperature is obtained. Besides, the lowest temperature for single dislocation emission before brittle fracture is also obtained by constructing an energy balance. The multi-scale analysis of facture toughness of the ferroelectric ceramics at high temperature is carried out. Through the analysis, the CAEFIF for crack extension is recalculated. The results show that the competition and interaction effects between dislocation emission and brittle fracture are very obvious. Besides, the higher critical activation temperature, the more columns of obstacles will be overcome. Additionally, the shielding effect arising from thermally activated dislocations is remarkable, thus, the brittle-ductile transition can promote the fracture toughness of high-temperature ferroelectric ceramics.