柳宗元牌蛇鞭酒HPLC指纹图谱研究

利用高效液相色谱建立了柳宗元牌蛇鞭酒的石油醚-乙醚提取物的指纹图谱,并检验了该产品的质量稳定性。实验条件为：反相C18柱,流速为1．0mL／min,UV检测器（λ=350nm）,流动相为甲醇,梯度洗脱,并利用Drylab软件进行色谱条件优化。分析和比较了不同批次的产品的统计指纹图谱的相对保留时间和积分面积,结果表明,12个批次的蛇鞭酒之间有15个共有指纹峰,各样品色谱图之间的相似度相差不大,均在0．951以上,说明12个批次样品的质量都很稳定;该方法易于操作,对产品质量的控制有明显的效果。     

Curcumin nanoemulsion for transdermal application: formulation and evaluation

The aim of this work is to develop a curcumin nanoemulsion for transdermal delivery. The incorporation of curcumin inside a nanoglobul should improve curcumin stability and permeability. A nanoemulsion was prepared by the self-nanoemulsification method, using an oil phase of glyceryl monooleate, Cremophor RH40 and polyethylene glycol 400. Evaluation of the nanoemulsion included analysis of particle size, polydispersity index, zeta potential, physical stability, Raman spectrum and morphology. In addition, the physical performance of the nanoemulsion in Viscolam AT 100P gel was studied. A modified vertical diffusion cell and shed snake skin of Python reticulatus were used to study the in vitro permeation of curcumin. A spontaneously formed stable nanoemulsion has a loading capacity of 350?mg curcumin/10?g of oil phase. The mean droplet diameter, polydispersity index and zeta potential of optimized nanoemulsion were 85.0?±?1.5?nm, 0.18?±?0.0 and ?5.9?±?0.3?mV, respectively. Curcumin in a nanoemulsion was more stable than unencapsulated curcumin. Furthermore, nanoemulsification significantly improved the permeation flux of curcumin from the hydrophilic matrix gel; the release kinetic of curcumin changed from zero order to a Higuchi release profile. Overall, the developed nanoemulsion system not only improved curcumin permeability but also protected the curcumin from chemical degradation.     

Automatic segmentation on multiple starch granules from microscopic images

Starch is the most important carbohydrate in the human diet and contained in many staple foods such as rice, wheat, corn, potatoes and cassava, etc. Currently, microscopic imaging technology is one of the most effective ways to investigate and analyze the structure of starches. Segmentation of starch granules is a necessary step for starch granule structure analysis such as starch granules detection, shape recognition, and size computation. This article investigates a new method based on GVF (gradient vector flow) snake deformable model for starch granules segmentation. The proposed method focuses on full automatic segmentation on granules, especially on separation of adjacent and contacted starch granules, which occur widely in microscopic images. A novel energy function based on position and intensity is introduced into the directional gradient computation, thus the directional gradient is used to obtain the directional GVF snake, which drives the deforming contours to the real contours of multiple granules. To demonstrate the good ability of the proposed method, we segment 30 starch granule images and compare it with the level set method, experimental results show that the new method can separate multiple starch granules successfully; especially it works much better on overlapping objects segmentation than the level set method.     

An experimental investigation of referential looking in free-ranging Barbary macaques (Macaca sylvanus).

The authors examined looking behavior between 15 Barbary macaque (Macaca sylvanus) infants and their mothers in the presence of a rubber snake (experimental period) and in the absence of the snake (control period). Two of the 15 infants looked referentially at their mother in the experimental period. Including both referential and nonreferential looks, the six older infants (aged 5 to 12 months) displayed a higher frequency of looks to mother than nine younger infants (aged 3 to 4.5 months) in the experimental period, but not in the control period. Older infants looked more to the mother in the experimental condition, whereas the younger infants looked more to the mother in the control condition, or looked equally in the two conditions. These results suggest that age is an important factor in determining looking behavior to mother in situations of uncertainty. Compared to hand-reared chimpanzees or human infants tested in standard social referencing paradigms, the infant macaques displayed a low rate of referential looking. Possible explanations for this are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

新型井下磁偶极子蛇形天线仿真设计

针对石油钻井井下天线工作在井筒钻井液及地层组成的特殊环境中,无线传输信号损耗大、难以可靠传输的问题,通过仿真建模,设计一种新型磁耦极子天线,具备高增益、抗干扰和小型化特点,实现井下无线数据的可靠传输。首先采用HFSS三维仿真软件构建仿真模型,详细将天线的长度、距离钻柱本体位置及天线的蛇形弯折数等关键参数进行计算,得出有效传输的参数组合和频点规律。据此规律,设计了天线实物,仿真结果与实物测试结果相比对,具有高度一致性,回波损耗可达到-7.5 dB以下,仿真设计的参数可以满足实际应用需求。该天线设计可应用于石油钻井井下无线传输,可提高信号发射强度,减小天线尺寸,降低系统功耗,实现无线信号可靠传输。     

Bleeding and Thrombosis: Insights into Pathophysiology of Bothrops Venom-Related Hemostasis Disorders

Toxins from Bothrops venoms targeting hemostasis are responsible for a broad range of clinical and biological syndromes including local and systemic bleeding, incoagulability, thrombotic microangiopathy and macrothrombosis. Beyond hemostais disorders, toxins are also involved in the pathogenesis of edema and in most complications such as hypovolemia, cardiovascular collapse, acute kidney injury, myonecrosis, compartmental syndrome and superinfection. These toxins can be classified as enzymatic proteins (snake venom metalloproteinases, snake venom serine proteases, phospholipases A₂ and L-amino acid oxidases) and non-enzymatic proteins (desintegrins and C-type lectin proteins). Bleeding is due to a multifocal toxicity targeting vessels, platelets and coagulation factors. Vessel damage due to the degradation of basement membrane and the subsequent disruption of endothelial cell integrity under hydrostatic pressure and tangential shear stress is primarily responsible for bleeding. Hemorrhage is promoted by thrombocytopenia, platelet hypoaggregation, consumption coagulopathy and fibrin(ogen)olysis. Onset of thrombotic microangiopathy is probably due to the switch of endothelium to a prothrombotic phenotype with overexpression of tissue factor and other pro-aggregating biomarkers in association with activation of platelets and coagulation. Thrombosis involving large-caliber vessels in B. lanceolatus envenomation remains a unique entity, which exact pathophysiology remains poorly understood.     

关于高压电力电缆在桥梁上敷设的方案设计要点

由于广州市地理位置位于珠三角的珠江人海口,电力电缆也因此成为市区内跨越江河湖海等水道的一种常用的输电方式。对于在桥梁上敷设电缆,需要同时考虑桥梁与电缆的结构特性以及各自运行的安全,因此对电缆线路的敷设形式有着特殊的要求。对110kV以上电压等级电力电缆在道路桥梁上的敷设方案进行讨论,提出主要设计要点以及敷设参数计算方法,可为将来的工程提供参考。     

引入蛇模型的曲率驱动扩散图像修复方法

数字图像修复方法可以自动地修复数字图像中用户定义的污损区域。T.F.Chan等人提出的非纹理的曲率驱动扩散算法是基于偏微分方程的图像修复的代表算法之一。通过在该算法中应用蛇模型的图像增强项,提出了引入蛇模型的曲率驱动扩散图像修复方法,在热扩散过程中,拉动曲线向目标边界演化,达到修复污损图像中的断裂边缘的目的,从而较好保持图像的视觉连通性。实验结果表明,在迭代次数相同的条件下,可以比原始的曲率驱动扩散图像修复算法获得更好的修复效果。     

To look or not to look: An eye movement study of hypervigilance during change detection in high and low spider fearful students.

Previous eye movement studies of attentional bias in spider fear reported inconsistent results with respect to early attentional capture, suggesting that overt attentional capture only reliably occurs under specific circumstances. In addition, none of these studies explored covert attention. The present study examined attentional bias in spider phobia using a change detection paradigm that was expected to provide good conditions for documenting attentional capture. In contrast to our expectations, eye movement data showed that all participants' first fixations were fastest on general negative targets, whereas participants' first fixations on spider targets were slower in the spider fearful than in the nonfearful group. In addition, spider fearful participants made more nontarget fixations before fixating on a spider target than did nonfearful participants. Thus, we found that participants' overt attention was more quickly focused on general negative targets, whereas covert attentional processes enabled initial avoidance of fear-relevant (i.e. spider) stimuli. The present findings have important implications for research on attention and fear as they indicate that fearful individuals are not characterized by static attentional orienting toward threat but, under certain conditions, may avert attention from threat automatically. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

铝合金蛇形轧制轧板曲率解析模型研究

根据蛇形轧制的受力特点将变形区划分为5个不同的区域,分别计算了各个区域的压力分布及角位移,在此基础上运用平面应变主应力法建立了7150铝合金蛇形轧制轧板曲率的解析模型.通过蛇形轧制实验对解析模型的精确性进行了验证.使用该解析模型对蛇形轧制过程中由线性应变差引起的轧板曲率、剪切应变差引起的轧板曲率以及总的轧板曲率进行了研究.结果表明,随着错位距离的增加由剪切应变差引起的轧板曲率增加而由线性应变差引起的轧板曲率减小,它们的共同作用导致总的轧板曲率先减小后增加.随着异速比的增加,由剪切应变差引起的轧板曲率增加,由线性应变差引起的轧板曲率保持不变,它们的共同效果使总的轧板曲率增加.增大轧板初始厚度或减小压下量都会减小轧板曲率.