Evaluating Visual Properties via Robust HodgeRank

International Journal of Computer Vision - Nowadays, how to effectively evaluate visual properties has become a popular topic for fine-grained visual comprehension. In this paper we study the...     

Red Emissive Carbon Dots Prepared from Polymers as an Efficient Nanocarrier for Coptisine Delivery in vivo and in vitro

Negatively charged fluorescent carbon dots (CDs, E_m=608 nm) were hydrothermally prepared from thiophene phenylpropionic acid polymers and then successfully loaded with the positively charged anticancer cargo coptisine, which suffers from poor bioavailability. The formed CD-coptisine complexes were thoroughly characterized by particle size, morphology, drug loading efficiency, drug release, cellular uptake and cellular toxicity in vitro and antitumor activities in vivo. In this nano-carrier system, red emissive CDs possess multiple advantages as follows: 1) high drug loading efficiency (>96 %); 2) sustained drug release; 3) enhanced drug efficacy towards cancer cells; 4) EPR effect; 5) drug release tracing with near-infrared imaging. These properties indicated that red emissive CDs prepared from polymers could be used as a novel drug delivery system with integrated therapeutic and imaging functions in cancer therapy, which are expected to have great potential in future clinical applications.     

Trapping Iron Oxide into Hollow Gold Nanoparticles

Synthesis of the core/shell-structured Fe₃O₄/Au nanoparticles by trapping Fe₃O₄ inside hollow Au nanoparticles is described. The produced composite nanoparticles are strongly magnetic with their surface plasmon resonance peaks in the near infrared region (wavelength from 700 to 800 nm), combining desirable magnetic and plasmonic properties into one nanoparticle. They are particularly suitable for in vivo diagnostic and therapeutic applications. The intact Au surface provides convenient anchorage sites for attachment of targeting molecules, and the particles can be activated by both near infrared lights and magnetic fields. As more and more hollow nanoparticles become available, this synthetic method would find general applications in the fabrication of core–shell multifunctional nanostructures.     

Schiff碱N，N’-二（2，5-二羟基水杨醛基）乙二胺与Co（Ⅱ）配合物的合成及晶体的培养

水杨醛类Schiff碱N,N’-二（2,5-二羟基水杨醛基）乙二胺和六水合氯化钴在一定条件下可以形成配合物。文章重点介绍了在常温下配体与碱的摩尔比为1：2、配体与金属盐的摩尔比为1：2时,用分层法培养出N,N’-二（2,5-二羟基水杨醛基）乙二胺和六水合氯化钴所形成的黑色针状单晶。     

枣果中酚类物质的高效液相色谱分析

建立了一种可同时测定11种酚类物质的高效液相色谱(HPLC)法,并对枣果中的酚类物质进行了分析测定。色谱条件为:Waters Symmetry C_(18)柱(4.6 mm×150 mm,5μm),流动相为甲醇和磷酸水(pH 2.6),280 nm和320 nm双波长紫外检测,柱温30℃,进样量5μL,流速0.6 mL/min,梯度洗脱程序:0 min 15%A,15～25 min 25%A,65 min 75%A,70 min 15%A,梯度线性变化。经测定,新鲜梨枣果内中含有儿茶素、表儿茶素、没食子酸、原儿茶酸、绿原酸和芦丁等酚类物质,其中儿茶素和表儿茶素占检测到的酚类物质总量的85%以上,未成熟果含量远高于成熟果。     

深水航道整治中新型结构淹没丁坝水流力特性研究

为研究新型结构淹没丁坝的水流力特性,基于有限体积法与自由液面捕捉法,通过流体计算软件Fluent建立三维数学模型对不同流速、水深与坝长条件下新型结构齿形丁坝的水流力特性进行研究。同时,设计了比尺为1:50的物理模型对不同坝长条件下新型结构丁坝水流力进行补充验证,数值模拟结果与试验结果符合良好。研究不仅得到了丁坝流场流速与水深的分布规律,同时分析了不同流速、水深与坝长条件下新型结构齿形丁坝的水流力响应规律,进而通过量纲处理分析了相对坝长与淹没度对水流力系数的响应规律,通过独立化分析的方法分别探讨了相对坝长与淹没度对丁坝水流力系数的敏感性。研究成果为新型淹没丁坝在长江南京以下12.5 m深水航道整治工程的应用提供一定的技术支撑与科学指导。     

沪通长江大桥墩位布设适应性分析

为深入研究沪通长江大桥桥墩布设合理性, 分析拟建桥梁对12.5 m深水航道以及船舶通航等的影响, 通过物理模型试验从水动力变化、河床冲淤变化、桥址河段通航条件等方面分析拟建桥梁墩位布设的适应性, 并对现有的桥位方案和主桥各通航孔向南平移200 m的方案进行了比选分析。同时, 于2010年4月和7月进行了桥区河段枯季大、小潮, 洪季大、小潮船筏走行线的现场测量。研究表明, 在桥位方案确定的情况下, 现有墩位方案稍优, 能满足实际航行需要。研究结果可为后续大桥建设提供一定的理论指导与技术支持。     

A Magnetofluorescent Carbon Dot Assembly as an Acidic H2O2‐Driven Oxygenerator to Regulate Tumor Hypoxia for Simultaneous Bimodal Imaging and Enhanced Photodynamic Therapy

Recent studies indicate that carbon dots (CDs) can efficiently generate singlet oxygen (¹O₂) for photodynamic therapy (PDT) of cancer. However, the hypoxic tumor microenvironment and rapid consumption of oxygen in the PDT process will severely limit therapeutic effects of CDs due to the oxygen‐dependent PDT. Thus, it is becoming particularly important to develop a novel CD as an in situ tumor oxygenerator for overcoming hypoxia and substantially enhancing the PDT efficacy. Herein, for the first time, magnetofluorescent Mn‐CDs are successfully prepared using manganese(II) phthalocyanine as a precursor. After cooperative self‐assembly with DSPE‐PEG, the obtained Mn‐CD assembly can be applied as a smart contrast agent for both near‐infrared fluorescence (FL) (maximum peak at 745 nm) and T₁‐weighted magnetic resonance (MR) (relaxivity value of 6.97 mM^?1 s^?1) imaging. More interestingly, the Mn‐CD assembly can not only effectively produce ¹O₂ (quantum yield of 0.40) but also highly catalyze H₂O₂ to generate oxygen. These collective properties of the Mn‐CD assembly enable it to be utilized as an acidic H₂O₂‐driven oxygenerator to increase the oxygen concentration in hypoxic solid tumors for simultaneous bimodal FL/MR imaging and enhanced PDT. This work explores a new biomedical use of CDs and provides a versatile carbon nanomaterial candidate for multifunctional nanotheranostic applications.     

IKid仿人足球机器人的自定位和球定位

仿人足球机器人的定位问题是机器人完成自主移动和智能决策的关键问题之一。介绍了本校IKid仿人足球机器人自身在球场的定位和足球在机器人坐标系的定位。前者通过自身内部九轴惯性传感器测量加速度、磁场方向和旋转角速度,并在此基础上通过粒子滤波和时间漂移修正等手段补偿误差完成机器人自身的位置和姿态计算。后者通过摄像头采集足球的视觉图像,在图像处理的基础上通过单目摄像机视觉系统完成在眼坐标系中足球三维坐标的计算,并通过手眼标定实现足球在机器人坐标系的定位。以上定位系统和定位方法已被应用于现有的IKid机器人,使其更好地完成动态行走、找球和踢球等动作。     

半连续液态深层发酵红枣醋及其抗氧化活性

以红枣酒为原料,采用巴氏醋酸杆菌（Acetobacter pasteurianus）进行半连续液态深层发酵,研究不同接种量和溶氧量对醋酸发酵的影响,并对发酵过程中有机酸的变化和红枣醋的抗氧化活性进行分析。结果表明,采用半连续液态深层发酵酿制红枣醋,在溶氧量10%、分割留种量50%的条件下,发酵周期可缩短到14.5～15.5 h。红枣酒醋酸发酵初期奎宁酸和苹果酸含量均增加1倍以上,但在后续的快速产酸阶段又逐渐降低至发酵前的水平,乳酸在发酵初期被转化,最终降低至43.55 mg/100 mL。红枣酒经过醋酸菌发酵后,其中的总酚和总黄酮含量以及1,1-二苯基-2-苦肼基（DPPH）自由基清除能力、Fe3+还原能力、2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）自由基清除能力分别提高16.59%、42.98%、24.66%、27.87%和38.07%,因此可作为增强红枣产品功能特性的加工手段。