人工神经网络技术用于酵母同化无机硒作用的研究

本文研究了啤酒酵母和假丝酵母对无机硒的同化能力,结果表明假丝酵母对无机硒的耐受力较强;并且假丝酵母对无机硒的同化能力和菌体产率均高于啤酒酵母．另外还研究了金属元素对假丝酵母同化无机硒及生长的影响,运用神经网络技术,以正交试验法构造训练样本,通过预测与优化,得出培养基中的无机金属元素的最佳含量．     

慢性肝炎患者91例庚型肝炎病毒抗体测定

目的：阐明HGV在慢性乙肝和慢性丙肝病人中的感染情况。方法：甩ELISA法检测上述二类对象的度型肝炎病毒抗体（抗—HGV）。结果：35例慢性丙肝中有13例阳性,阳性率为37．1％。56例慢性乙肝中有5例阳性,阳性率为8．9％。结论：侵性肝炎合并HGV感染率较高,尤其是慢性丙肝。可能是HBV和HCV感染易慢性化的原因之一,但较单一HBV和HCV感染的临床表现无明显加重趋势。     

一般化凸空间上的Ky Fan型重叠定理和不动点定理

在本文，我们根据已有的结论得到了若干个一般化凸空间上Ky Fan型重叠定理和Fan-Browder型不动点定理。     

The adhesion receptor GPR56 is activated by extracellular matrix collagen III to improve β-cell function

Aims

G-protein coupled receptor 56 (GPR56) is the most abundant islet-expressed G-protein coupled receptor, suggesting a potential role in islet function. This study evaluated islet expression of GPR56 and its endogenous ligand collagen III, and their effects on β-cell function.

Methods

GPR56 and collagen III expression in mouse and human pancreas sections was determined by fluorescence immunohistochemistry. Effects of collagen III on β-cell proliferation, apoptosis, intracellular calcium ([Ca²⁺]_i) and insulin secretion were determined by cellular BrdU incorporation, caspase 3/7 activities, microfluorimetry and radioimmunoassay, respectively. The role of GPR56 in islet vascularisation and innervation was evaluated by immunohistochemical staining for CD31 and TUJ1, respectively, in pancreases from wildtype (WT) and Gpr56^?/? mice, and the requirement of GPR56 for normal glucose homeostasis was determined by glucose tolerance tests in WT and Gpr56^?/? mice.

Results

Immunostaining of mouse and human pancreases revealed that GPR56 was expressed by islet β-cells while collagen III was confined to the peri-islet basement membrane and islet capillaries. Collagen III protected β-cells from cytokine-induced apoptosis, triggered increases in [Ca²⁺]_i and potentiated glucose-induced insulin secretion from WT islets but not from Gpr56^?/? islets. Deletion of GPR56 did not affect glucose-induced insulin secretion in vitro and it did not impair glucose tolerance in adult mice. GPR56 was not required for normal islet vascularisation or innervation.

Conclusion

We have demonstrated that collagen III improves islet function by increasing insulin secretion and protecting against apoptosis. Our data suggest that collagen III may be effective in optimising islet function to improve islet transplantation outcomes, and GPR56 may be a target for the treatment of type 2 diabetes.

     

鞘铁菌(Siderocapsa)固锰的生化分析

从鞍山大赵台天然水滤池中分离出固锰能力很强的二种鞘铁菌,经胰酶处理菌体表面,破碎菌体,以及用胰酶和酶抑制剂处理菌体破碎后的内含物等实验表明,鞘铁菌的固锰能力可能是由于菌体内具有固锰能力的酶系所致。     

New developments of MSRT’s working modes: One-dimensional radio heliograph and IPS telescope

This note introduces the newly developed working modes, i.e. one-dimensional meter-wave radio heliograph (MRH) and interplanetary scintillation (IPS) telescope, of meter-wave aperture synthesis radio telescope (MSRT) at Beijing Astronomical Observatory (BAO). The note describes briefly the scientific objectives, configurations of the hardware and software, and functions of the system. It presents the examples of observations on solar meter-wave bursts and IPS with the two new working modes. The results indicated that new modes not only can provide the information on the evolution of solar activities with space and time, but also can trace and monitor the propagation and spatial distribution of interplanetary plasma shock resulting from solar activities and the instability of the ionosphere, etc. Both modes are new facilities that could fill the gaps in scientific frontiers.     

自来水厂除锰滤池Mn~(2+)氧化细菌的分离及其活性的研究

从沈阳石佛寺自来水厂除锰滤池中分离得到7株能够催化Mn2+氧化的细菌，并就催化因子的分离作了尝试．结果表明，Mn2+诱导催化氧化能力，催化活性因子在细胞上；培养基中的有机物浓度影响活性表达，有机物浓度升高，细菌生长加快，但活性表达被抑制．     

Mn对镁合金中杂质元素Si分布的影响

为了研究Mn元素对镁合金中杂质元素Si去除效果的影响,使用热力学与动力学模拟软件Pandat从理论上计算了最佳Mn添加量为2.5%(质量分数),通过静置保温工艺制备了Mg-2.5%Mn合金,采用X射线荧光光谱分析(XRF)、金相显微镜、扫描电子显微镜(SEM)、X射线衍射(XRD)等检测了合金的成分、组织和物相等。研究结果表明:合金中的杂质元素Si与Mn形成密度较大的含Si、Mn的化合物,化合物在静置过程中沉降到合金底部,合金底部杂质Si的含量很高,质量分数达到0.074 1%,顶部杂质Si含量很少(质量分数为0.013 0%),中部几乎为0。Mn的添加可以有效地去除镁合金的杂质元素Si和Fe。     

湍流激励下单双层圆柱壳振动特性对比

基于随机理论,采用半解析半数值方法,以单双层圆柱壳模型为例,计算了湍流激励下单双层圆柱壳的输入功率谱密度和振动速度功率谱密度,对比分析了单双层圆柱壳的振动特性.结果表明：随着航速增高,湍流脉动压力激起壳体表面振动速度的自功率谱密度幅值变大,趋势基本相同;同一航速下,湍流脉动压力作为面分布力作用在壳体外表面上,由于双壳体的外壳较薄,因此双壳体振动速度响应大于单壳体的.     

互惠共存种群具有常数收获率的二维VOLTERRA模型的全局定性分析

文［１－３］提出的二维Ｖｏｌｔｅｒｒａ模型：文［４－６］讨论了（Ｅ）为捕食与被捕食者关系及竞争关系时的定性性质，本文讨论了（Ｅ）为互惠共存关系时的全局定性性质，得到了所作出全局相图的充要条件：△＝ａ１１ａ２２－ａ１２ａ２１＞０．