A Framework for Web-Based Mechanical Design and Analysis

In this paper, a Web-based Mechanical Design and A na lysis Framework (WMDAF) is proposed. This WMADF allows designers to develop web -based computer aided programs in a systematic way during the collaborative mec hanical system design and analysis process. This system is based on an emerg ing web-based Content Management System (CMS) called eXtended Object Oriented P ortal System (XOOPS). Due to the Open Source Status of the XOOPS CMS, programs d eveloped with this framework can be further customized to ...     

Water,a powerful attractant for the gravid females of Plodia interpunctella and Cadra cautella

Summary In the sex pheromone controlling experiments, not only large number of the males of the almond moth and Indian meal moth, but also great number of ovipositional females were caught. The increased catch of the fertilized females was due to the presence of detergent in the water.     

磷酸二氢铵单晶培养的一些问题

研究了ＡＤＰ晶片的截面大小,表面状况和转动方式以及溶液的过饱和度等因素对“成锥” 过程的影响。初步得出了在晶片边界完整性较好和采用定时换向的条件下,溶液的过饱和度略高 一些对“成锥”比较有利。对深液的ｐＨ值和晶体的转动方式对晶体成长的影响也进行了初步探 讨。另一方面比较详细地研究了晶体在培养器中的取向对ＡＤＰ晶面生长速率和晶体生长习性的 影响,初步确定了维持晶体匀称生长较好的空间取向。最后对上述ＡＤＰ晶体培养的一些规律提 出了初步讨论。     

Architecture of ribonucleoprotein complexes in influenza A virus particles

In viruses, as in eukaryotes, elaborate mechanisms have evolved to protect the genome and to ensure its timely replication and reliable transmission to progeny. Influenza A viruses are enveloped, spherical or filamentous structures, ranging from 80 to 120 nm in diameter. Inside each envelope is a viral genome consisting of eight single-stranded negative-sense RNA segments of 890 to 2,341 nucleotides each. These segments are associated with nucleoprotein and three polymerase subunits, designated PA, PB1 and PB2; the resultant ribonucleoprotein complexes (RNPs) resemble a twisted rod (10-15 nm in width and 30-120 nm in length) that is folded back and coiled on itself. Late in viral infection, newly synthesized RNPs are transported from the nucleus to the plasma membrane, where they are incorporated into progeny virions capable of infecting other cells. Here we show, by transmission electron microscopy of serially sectioned virions, that the RNPs of influenza A virus are organized in a distinct pattern (seven segments of different lengths surrounding a central segment). The individual RNPs are suspended from the interior of the viral envelope at the distal end of the budding virion and are oriented perpendicular to the budding tip. This finding argues against random incorporation of RNPs into virions, supporting instead a model in which each segment contains specific incorporation signals that enable the RNPs to be recruited and packaged as a complete set. A selective mechanism of RNP incorporation into virions and the unique organization of the eight RNP segments may be crucial to maintaining the integrity of the viral genome during repeated cycles of replication.     

Identification of the gene (BBS1) most commonly involved in Bardet-Biedl syndrome,a complex human obesity syndrome

Bardet-Biedl syndrome (BBS, OMIM 209900) is a genetic disorder with the primary features of obesity, pigmentary retinopathy, polydactyly, renal malformations, mental retardation and hypogenitalism. Individuals with BBS are also at increased risk for diabetes mellitus, hypertension and congenital heart disease. What was once thought to be a homogeneous autosomal recessive disorder is now known to map to at least six loci: 11q13 (BBS1), 16q21 (BBS2), 3p13 p12 (BBS3), 15q22.3 q23 (BBS4), 2q31 (BBS5) and 20p12 (BBS6). There has been considerable interest in identifying the genes that underlie BBS, because some components of the phenotype are common. Cases of BBS mapping ro BBS6 are caused by mutations in MKKS; mutations in this gene also cause McKusick-Kaufman syndrome (hydrometrocolpos, post-axial polydactyly and congenital heart defects). In addition, we recently used positional cloning to identify the genes underlying BBS2 (ref. 16) and BBS4 (ref. 17). The BBS6 protein has similarity to a Thermoplasma acidophilum chaperonin, whereas BBS2 and BBS4 have no significant similarity to chaperonins. It has recently been suggested that three mutated alleles (two at one locus, and a third at a second locus) may be required for manifestation of BBS (triallelic inheritance). Here we report the identification of the gene BBS1 and show that a missense mutation of this gene is a frequent cause of BBS. In addition, we provide data showing that this common mutation is not involved in triallelic inheritance.