PROJECTILE FRAGMENTATION OF Ar-36,Ar-40 INDUCED REACTIONS

Fragment yields for Z >= 5 from projectile fragmentation using primary beams of Ar-36,Ar-40 at 50 MeV/nucleon on Ni-64 target have been measured in RIBLL fragment separator. We compare the fragment cross sections with the predictions of the empirical EPAX parametrization of fragmentation cross-sections and Statistical Abration-Ablation model (SAA) by considering the RIBLL separator transmission rate. Isotope yield ratios between these two reactions were calculated and isoscaling parameters alpha and beta are extracted, their dependences on fragment atomic number Z and neutron number N were presented.

30,35MeV/u 36,40Ar＋112,124Sn反应中热核性质同位旋效应的实验研究

针对①中能反应中同位旋自由度是否达到平衡，②同位旋自由度对几中不同方法测量的核温度是否有影响 这两个基本问题，设计了用30和35MeV/u ~(36,40)Ar轰击~(112,124)Sn反应的实验方案。得到如下结果：对于前角5°处的耗散弹核碎裂产物，丰中子同位素与稳定核的产额比随产物出射动能的增加而减小，而丰质子子同位素与稳定核的产额比随动能的增加而增加，呈现明显的剪刀差分布特性。随耗散时间的增大，产物的平均中质比逐渐由弹核的平均中质比向系统的平均中质比过渡。这个结果说明在该反应中，同位旋自由度没有达到完全平衡。而对于20°处的DIC产物，上述剪刀差分布特性变得更不明显，这是同位旋自由度由非平衡向平衡过渡的表现。后角轻粒子的能谱分析表明，初始热核的同位旋会影响斜率核温度的提取，由于丰中子轻粒子~6He在~(40)Ar + ~(112)Sn系统中的蒸发被抑制，相比~(40)Ar + ~(112)Sn而言，其蒸发比较容易发生在衰变链早期，因此提取的温度偏高，同样，丰质子轻粒子~3He的温度在~(40)Ar + ~(112)Sn中略高。但中后角的同位素产额分析表明，反应系统的同位旋对双同位素比核温度几乎没有影响。核温度作为热核的热力学量，是独立于测量方法的，这种不同的方法得出的差异主要来源于同位旋对衰变机制的影响。作为一个尝试，将中高能反应中的熵的提取推广到这个能区，发现两个系统的熵几乎一致。在量子统计模型框架下，考察核温度与熵的关系发现，~(40)Ar + ~(112)Sn反应的挤出时刻密度略高于~(40)Ar + ~(112)Sn。

36单元塑料闪烁体陈列探测器制作与调试

本文描述了一个能在中解（10－100Mev/u）重离子核反应测量中鉴别轻粒子，测量粒子多重性，并能给出轻粒子能量和位置信息的大立体角（θ: 5°-20°φ: 0°-360°）的36单元塑料闪烁体陈列探测器的制作与调试，初步调试结果表明该探测器对轻粒子（p、α等）有较好的分辨。同时对国际上几种规模较大的先进的多单元大立体角粒子探测系统作了比较全面的介绍

Synthesis and characterization of the nanoporous ultrathin multilayer films based on molybdenum polyoxometalate (Mo-36)(n)

Ultrathin multilayer films of the wheel-shaped molybdenum polyoxometalate cluster (Mo-36)(n) and poly(allylamine hydrochloride) (PAH) have been prepared by the layer-by-layer (LbL) self-assembly method. The ((Mo-36)(n)/PAH)(m) multilayer films have been characterized by Xray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). UV-VIS measurements reveal regular film growth with each (Mo-36)(n) adsorption. The electrochemical behavior of the film at room temperature was investigated.

The chemistry of alpha-oxo ketene cyclic dithioacetal .36. Studies on silica G catalyzed decomposition of adducts of beta,beta-1,3-propylenedithio-alpha,beta-unsaturated arylketones with grignard reagents

beta, beta-1, 3-Piopylenedithio-alpha, beta-unsaturated arylketones 2 via chemoselective 1,2-addition with allyl or benzyl Grignard reagents afforded the corresponding carbinols 3 and 4. Catalysed by silica gel, the carbinols 3 and 4 were converted to the beta,gamma-unsaturated arylketones 5, 6. The mechanism and reaction condition were discussed.

Practice links [Issue 36, February 2010]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 36 features articles on equine assisted personal development, the National Child Care Information System and a report on Fieldwork Training for Social Workers

Yeast screens identify the RNA polymerase II CTD and SPT5 as relevant targets of BRCA1 interaction.

BRCA1 has been implicated in numerous DNA repair pathways that maintain genome integrity, however the function responsible for its tumor suppressor activity in breast cancer remains obscure. To identify the most highly conserved of the many BRCA1 functions, we screened the evolutionarily distant eukaryote Saccharomyces cerevisiae for mutants that suppressed the G1 checkpoint arrest and lethality induced following heterologous BRCA1 expression. A genome-wide screen in the diploid deletion collection combined with a screen of ionizing radiation sensitive gene deletions identified mutants that permit growth in the presence of BRCA1. These genes delineate a metabolic mRNA pathway that temporally links transcription elongation (SPT4, SPT5, CTK1, DEF1) to nucleopore-mediated mRNA export (ASM4, MLP1, MLP2, NUP2, NUP53, NUP120, NUP133, NUP170, NUP188, POM34) and cytoplasmic mRNA decay at P-bodies (CCR4, DHH1). Strikingly, BRCA1 interacted with the phosphorylated RNA polymerase II (RNAPII) carboxy terminal domain (P-CTD), phosphorylated in the pattern specified by the CTDK-I kinase, to induce DEF1-dependent cleavage and accumulation of a RNAPII fragment containing the P-CTD. Significantly, breast cancer associated BRCT domain defects in BRCA1 that suppressed P-CTD cleavage and lethality in yeast also suppressed the physical interaction of BRCA1 with human SPT5 in breast epithelial cells, thus confirming SPT5 as a relevant target of BRCA1 interaction. Furthermore, enhanced P-CTD cleavage was observed in both yeast and human breast cells following UV-irradiation indicating a conserved eukaryotic damage response. Moreover, P-CTD cleavage in breast epithelial cells was BRCA1-dependent since damage-induced P-CTD cleavage was only observed in the mutant BRCA1 cell line HCC1937 following ectopic expression of wild type BRCA1. Finally, BRCA1, SPT5 and hyperphosphorylated RPB1 form a complex that was rapidly degraded following MMS treatment in wild type but not BRCA1 mutant breast cells. These results extend the mechanistic links between BRCA1 and transcriptional consequences in response to DNA damage and suggest an important role for RNAPII P-CTD cleavage in BRCA1-mediated cancer suppression.

Cinética de sobrevivencia de Rhizobium meliloti B - 36 sobre semilla preinoculada con diferentes adhesivos y coberturas

p.167-171