Synchrotron refractive-index microradiography of human liver cancer tissue

Three human liver tissue samples （-5 mm × 40 mm × 20 mm） were excised from a cancer patient＇s liver during surgery. The microradiology analysis was performed with a non-standard approach on a synchrotron. High-resolution refractive-index edge-enhanced microradiographs that cover a larger volume of the liver tissue sample were obtained. The cancer tissue and normal tissue could be clearly identified and distinguished based on their different textures. Furthermore, new blood vessel hyperplasia was found near the cancer area. Blood vessels with a diameter smaller than 20 μm could be identified. These findings were fully consistent with the histopathological examination or the same area. Microradiographs of the newly formed blood vessels at different angles were also obtained. This result shows that it is possible to further develop this approach into a technique of microradiographic imaging for clinic diagnosis of liver cancer at the early stage.     

In Situ XRD and XAS Investigation of Cathode Materials in Li-ion Battery

1 Results Lithium ion batteries have been widely used in modern portable electronics,such as cellular phones and notebook computers,because of their low cost,long life,and high energy density.In the lithium ion batteries,the cathode provides lithium ion source and plays a critical role to determinate the performance of battery.Lithium transition metal oxides have been investigated as active cathode materials due to their high potential versus Li/Li and large proportion of the lithium ions can be insert...     

Coherent quantum phase slip

A hundred years after the discovery of superconductivity, one fundamental prediction of the theory, coherent quantum phase slip (CQPS), has not been observed. CQPS is a phenomenon exactly dual to the Josephson effect; whereas the latter is a coherent transfer of charges between superconducting leads, the former is a coherent transfer of vortices or fluxes across a superconducting wire. In contrast to previously reported observations of incoherent phase slip, CQPS has been only a subject of theoretical study. Its experimental demonstration is made difficult by quasiparticle dissipation due to gapless excitations in nanowires or in vortex cores. This difficulty might be overcome by using certain strongly disordered superconductors near the superconductor-insulator transition. Here we report direct observation of CQPS in a narrow segment of a superconducting loop made of strongly disordered indium oxide; the effect is made manifest through the superposition of quantum states with different numbers of flux quanta. As with the Josephson effect, our observation should lead to new applications in superconducting electronics and quantum metrology.     

Electrochemistry: building on bubbles in metal electrodeposition

In the electrodeposition of metals, a widely used industrial technique, bubbles of gas generated near the cathode can adversely affect the quality of the metal coating. Here we use phase-contrast radiology with synchrotron radiation to witness directly and in real time the accumulation of zinc on hydrogen bubbles. This process explains the origin of the bubble-shaped defects that are common in electrodeposited coatings.     

p63 and p73 are required for p53-dependent apoptosis in response to DNA damage

The tumour-suppressor gene p53 is frequently mutated in human cancers and is important in the cellular response to DNA damage. Although the p53 family members p63 and p73 are structurally related to p53, they have not been directly linked to tumour suppression, although they have been implicated in apoptosis. Given the similarity between this family of genes and the ability of p63 and p73 to transactivate p53 target genes, we explore here their role in DNA damage-induced apoptosis. Mouse embryo fibroblasts deficient for one or a combination of p53 family members were sensitized to undergo apoptosis through the expression of the adenovirus E1A oncogene. While using the E1A system facilitated our ability to perform biochemical analyses, we also examined the functions of p63 and p73 using an in vivo system in which apoptosis has been shown to be dependent on p53. Using both systems, we show here that the combined loss of p63 and p73 results in the failure of cells containing functional p53 to undergo apoptosis in response to DNA damage.     

负载型水相膦铑配合物催化剂上丙烯氢甲酰化制了醛

用连续流动加压微反－色谱装置评价了负载型水溶性膦铑催化剂对丙烯氢甲酰化制了醛的反应活性，结果表明，催化剂活性与体系中水含量密切相关，适量的水可使催化剂活性明显提高，原位红外光谱考察结果显示，当催化剂吸附ＣＯ时在２０４０、２０１２、１９０１ｃｍ－１等处出现一系列可归属于可逆吸附ＣＯ物种的伸缩振动带；通入原料气丙烯／ＣＯ／Ｈ２时，很快可观测到～１７１４ｃｍ－１附近的醛基吸收峰．实验结果表明，水溶性膦铑配合物负载到固体表面后，在载体表面与体系中微量水形成液膜，于气／液膜（固）界面可能有利于丙烯氢甲酰化配位络合催化循环的进行．     

Conversion of p35 to p25 deregulates Cdk5 activity and promotes neurodegeneration

Cyclin-dependent kinase 5 (Cdk5) is required for proper development of the mammalian central nervous system. To be activated, Cdk5 has to associate with its regulatory subunit, p35. We have found that p25, a truncated form of p35, accumulates in neurons in the brains of patients with Alzheimer's disease. This accumulation correlates with an increase in Cdk5 kinase activity. Unlike p35, p25 is not readily degraded, and binding of p25 to Cdk5 constitutively activates Cdk5, changes its cellular location and alters its substrate specificity. In vivo the p25/Cdk5 complex hyperphosphorylates tau, which reduces tau's ability to associate with microtubules. Moreover, expression of the p25/Cdk5 complex in cultured primary neurons induces cytoskeletal disruption, morphological degeneration and apoptosis. These findings indicate that cleavage of p35, followed by accumulation of p25, may be involved in the pathogenesis of cytoskeletal abnormalities and neuronal death in neurodegenerative diseases.     

稀土基复合物丙烷氧化脱氢制丙烯催化剂的研究

研制了用于丙烷氧化脱氢的稀土基含氟复合物催化剂,在反应温度为500℃,6000h~(-1)的空速条件下,丙烷转化率可达45.6％,丙烯单程收率可达34.8％,Raman光谱和XPS的结果表明,O~-_2是可能的活性氧物种,Cs_2O的加入对于产生和稳定O~-_2具有重要的作用。