Minor actinide transmutation in fast reactor metal fuels irradiated for 120 and 360 equivalent full-power days

An irradiation experiment on uranium–plutonium–zirconium (U–Pu–Zr) alloys containing 5 wt% or less minor actinides (MAs) and rare earths was carried out in the Phénix fast reactor. The isotope compositions of the fuel alloys irradiated for 120 and 360 equivalent full-power days (EFPDs) were chemically analyzed by inductively coupled plasma–mass spectrometry after 3.3–5.3 years of cooling. The results of chemical analysis indicated that the discharged burnups of the fuel alloys irradiated for 120 and 360 EFPDs were 2.1–2.5 and 5.3–6.4 at%, respectively. The changes in the isotopic abundances of plutonium, americium, and curium during the irradiation experiment were assessed to discuss the transmutation performance of MA nuclides added to U–Pu–Zr alloy fuel. Multigroup three-dimensional diffusion and burnup calculations accurately predicted the changes in these isotopic abundances after fuel fabrication. An evaluation of the MA transmutation ratio based on the results of chemical analysis revealed that the quantity of MA elements in the U–19Pu–10Zr–5MA (wt%) alloy decreased by about 20% during the irradiation experiment for 360 EFPDs.     

Optimal conditions for labelling of 3T3 fibroblasts with magnetoliposomes without affecting cellular viability

A comparative study that deals with the internalisation of different types of magnetoliposomes (MLs) by 3T3 fibroblasts revealed that cationic MLs proved to be superior to neutral and anionic ones. Internalisation was visualised both by optical light and transmission electron microscopy. The latter showed that the cationic MLs ultimately ended up in lysosomal structures. The effect of increasing 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) concentrations in the cationic ML coat has been elucidated. High uptake efficiency was only achieved with MLs that carry a high DOTAP payload. However, these structures also demonstrated toxic effects. The use of the saturated distearoyl analogue (DSTAP) at identical concentrations led to improved uptake efficiency and lower toxicity. By using iron-oxide-free vesicles, it was shown that the toxicity was due to lipid bilayer constituents and not the iron oxide. In conclusion, the use of DMPC-DSTAP (96.67:3.33; molar ratio) MLs results in an extremely high labelling of 3T3 fibroblasts with iron oxides (47.66 pg Fe per cell) without evoking any influence on cell viability.     

Increasing Angiogenesis Factors in Hypoxic Diabetic Wound Conditions by siRNA Delivery: Additive Effect of LbL-Gold Nanocarriers and Desloratadine-Induced Lysosomal Escape

Impaired wound healing in people with diabetes has multifactorial causes, with insufficient neovascularization being one of the most important. Hypoxia-inducible factor-1 (HIF-1) plays a central role in the hypoxia-induced response by activating angiogenesis factors. As its activity is under precise regulatory control of prolyl-hydroxylase domain 2 (PHD-2), downregulation of PHD-2 by small interfering RNA (siRNA) could stabilize HIF-1α and, therefore, upregulate the expression of pro-angiogenic factors as well. Intracellular delivery of siRNA can be achieved with nanocarriers that must fulfill several requirements, including high stability, low toxicity, and high transfection efficiency. Here, we designed and compared the performance of layer-by-layer self-assembled siRNA-loaded gold nanoparticles with two different outer layers—Chitosan (AuNP@CS) and Poly L-arginine (AuNP@PLA). Although both formulations have exactly the same core, we find that a PLA outer layer improves the endosomal escape of siRNA, and therefore, transfection efficiency, after endocytic uptake in NIH-3T3 cells. Furthermore, we found that endosomal escape of AuNP@PLA could be improved further when cells were additionally treated with desloratadine, thus outperforming commercial reagents such as Lipofectamine^® and jetPRIME^®. AuNP@PLA in combination with desloratadine was proven to induce PHD-2 silencing in fibroblasts, allowing upregulation of pro-angiogenic pathways. This finding in an in vitro context constitutes a first step towards improving diabetic wound healing with siRNA therapy.     

释放阳光地带的光伏发电潜力

拥有非常丰富的太阳能辐射资源的阳光地带,人口占全球人口总数的75%,电力需求占全球总需求的40%,该地区经济发展受到能源和环境的制约,充分利用丰富的太阳能辐射资源开发光伏发电产业,是可持续发展的重要手段。预测结果表明,范式转型情景中,这些国家的光伏装机容量甚至可达1 100 GW,也就是该地域发电总量的12%;2020年阳光地带国家光伏系统的发电成本将比建设天然气和燃油电站更具竞争力;至2030年光伏发电可以与所有以煤和天然气为燃料的中负荷电厂竞争。阳光地带国家发展股份发电目前还面临着许多障碍,这些障碍涉及到政府对燃油价格的补贴、服务于市场的能力以及能源公司的知识有限等,这些障碍有待于在发展过程中不断克服。中国和印度是阳光地带中的大国,两国的光伏制造业对阳光地带的影响很大。新能源被锁定为中国十二五规划的七大战略性新兴产业之一,中国的十二.五规划的重心是重新平衡经济增长模式,包括逐步扩大内需;国内光伏市场一旦打开,光伏在中国的发展将会非常迅速。释放阳光地带光伏潜力要求众多利益相关者共同参与协作,包括政府、银行和金融机构以及各行各业的支持,才能充分释放阳光地带的光伏发电潜力,带动光伏发电产业链的发展,成为社会经济...     

Targeted Liposome‐Loaded Microbubbles for Cell‐Specific Ultrasound‐Triggered Drug Delivery

One of the main problems in cancer treatment is disease relapse through metastatic colonization, which is caused by circulating tumor cells (CTCs). This work reports on liposome‐loaded microbubbles targeted to N‐cadherin, a cell–cell adhesion molecule expressed by CTCs. It is shown that such microbubbles can indeed bind to N‐cadherin at the surface of HMB2 cells. Interestingly, in a mixture of cells with and without N‐cadherin expression, binding of the liposome‐loaded microbubbles mainly occurs to the N‐cadherin‐expressing cells. Importantly, applying ultrasound results in the intracellular delivery of a model drug (loaded in the liposomes) in the N‐cadherin‐expressing cells only. As described in this paper, such liposome‐loaded microbubbles may find application as theranostics and in devices aimed for the specific killing of CTCs in blood.