热局部非平衡下饱和多孔弹性柱体的拟静态分析

基于多孔介质理论所建立的不可压饱和多孔介质热一流一同耦合模型,对于一端同定、绝热和不可渗透,另一端受机械和温度载荷联合作用且可自由排水的多孔弹性柱体,利用分离变量法和拉普拉斯变换推导给出了热局部非平衡下多孑L弹性柱体拟静态问题的一般解析表达式.最后,针对阶梯机械和温度载荷联合作用的情况,数值研究了不同参数下温度载荷对固相变形和有效应力、流体速度和孔隙压力的影响.结果表明:在流固两相热扩散系数的比值较大和两相间热交换系数比较小的情况下,热局部平衡和非平衡下有关结果之间的差异在初始阶段是非常明显的.     

Testosterone and eye-brain asymmetry for copulation in chickens

Summary Asymmetry of eye function has been demonstrated in the young chicken. Precocious copulation following intramuscular treatment with testosterone can be elicited by presentation of an appropriate stimulus to the left eye, but not to the right eye.     

高炉渣合成Ca-α-Sialon-SiC粉的热力学分析及工艺优化

在热力学分析的基础上，以高炉渣为原料，引入适当的添加剂，利用碳热还原－氮化的方法制备了Ｃａ－α－Ｓｉａｌｏｎ－ＳｉＣ粉，得到的Ｃａ－α－Ｓｉａｌｏｎ含量最高可以达到８１％；利用统计模式识别结合人工神经元网络优化了工艺．     

Evolutionary differentiation within the northern Great Basin pocket gopher, Thomomys townsendii II. Genetic variation and biogeographic considerations

Geographic and nongeographic variation in morphology was examined in Thomomys townsendii . A univariate analysis of external and cranial characters from a large population sample (66 adults; fusion of cranial sutures used as aging criteria) was used to assess variation among three adult age classes and between sexes. Only minor variation is apparent among age classes; however, sexual dimorphism is pronounced. Univariate and multivariate techniques were used to analyze external and cranial measurements and pelage characters for adults throughout the species range. These analyses show little to support the seven subspecific designations recognized by Davis (1937). The general pattern is one of homogeneity throughout the range of Thomomys townsendii . With the possible exception of T. t. nevadensis samples, current subspecies are not defined as morphological units. In fact, differentiation is found among populations within some subspecies. The most apparent pattern seen in these analyses is the divergence between the Humboldt River (including Honey Lake Valley samples) and Snake River systems. These results will be considered with those of a companion paper on the genetic variation in this species to more adequately assess the patterns of differentiation in Thomomys townsendii .     

Defects in whirlin,a PDZ domain molecule involved in stereocilia elongation,cause deafness in the whirler mouse and families with DFNB31

The whirler mouse mutant (wi) does not respond to sound stimuli, and detailed ultrastructural analysis of sensory hair cells in the organ of Corti of the inner ear indicates that the whirler gene encodes a protein involved in the elongation and maintenance of stereocilia in both inner hair cells (IHCs) and outer hair cells (OHCs). BAC-mediated transgene correction of the mouse phenotype and mutation analysis identified the causative gene as encoding a novel PDZ protein called whirlin. The gene encoding whirlin also underlies the human autosomal recessive deafness locus DFNB31. In the mouse cochlea, whirlin is expressed in the sensory IHC and OHC stereocilia. Our findings suggest that this novel PDZ domain-containing molecule acts as an organizer of submembranous molecular complexes that control the coordinated actin polymerization and membrane growth of stereocilia.     

The ‘mauve factor’ of schizophrenia and porphyria, 5-hydroxyhaemopyrrole lactam,has low pharmacological potency on guinea-pig ileum

Summary 5-Hydroxyhaemopyrrole lactam, the mauve factor reported in the urine of schizophrenics and porphyrics was found to inhibit electrically-stimulated contractions of guinea-pig ileum only at high concentrations (ID₅₀=8.5 mM). This low potency makes it unlikely that the compound can account for neurotoxic effects in human porphyria.We thank the Wellcome Trust for a grant.     

机械活化粉末制备W-Cu合金的微观组织

为了改善制备工艺和提高W-Cu合金的密度与性能,对原料粉末进行了机械活化处理,通过成形和烧结制备了W-Cu合金,考察了活化后粉末的变化,观察了合金的烧结组织并测量了密度.结果表明,机械活化能增大钨铜粉末的表面能和晶格畸变能,有效地促进烧结,改善烧结组织;烧结体中存在大量团絮状组织,团粒内部钨颗粒主要以固相方式烧结在一起,而团粒之间则以液相烧结为主.烧结组织细密、均匀,相对密度达98%以上;烧结组织中钨铜两相在微米尺度下仍然结合良好,部分界面出现了互溶.     

An SNP map of human chromosome 22

The human genome sequence will provide a reference for measuring DNA sequence variation in human populations. Sequence variants are responsible for the genetic component of individuality, including complex characteristics such as disease susceptibility and drug response. Most sequence variants are single nucleotide polymorphisms (SNPs), where two alternate bases occur at one position. Comparison of any two genomes reveals around 1 SNP per kilobase. A sufficiently dense map of SNPs would allow the detection of sequence variants responsible for particular characteristics on the basis that they are associated with a specific SNP allele. Here we have evaluated large-scale sequencing approaches to obtaining SNPs, and have constructed a map of 2,730 SNPs on human chromosome 22. Most of the SNPs are within 25 kilobases of a transcribed exon, and are valuable for association studies. We have scaled up the process, detecting over 65,000 SNPs in the genome as part of The SNP Consortium programme, which is on target to build a map of 1 SNP every 5 kilobases that is integrated with the human genome sequence and that is freely available in the public domain.