食尚健康 -芬美意的美味诠释

随着收入水平和健康意识的不断提高,消费者对食品饮料的健康营养价值提出了越来越高的要求,为了满足消费者的需求,食品饮料公司推出了众多健康诉求的新产品,已经成为全球范围内的最主要趋势之一.但健康产品往往因为无糖、低糖(使用甜味剂)、低脂、低盐或添加其它功能成分或提取物(多有异味)等等,造成产品口味不佳,影响到消费者食用此类健康产品,同时也影响到食品饮料公司的效益,我司针对此种情况,采用尖端技术,精选高效成分,已经开发出相应的改善口味口感的新功能性香精.主题一全球食品饮料健康趋势纵览;主题二芬美意新产品新技术介绍;主题三新产品概念&品评饮料,甜味食品,咸味食品     

A novel allele of Saccharomyces cerevisiae RFA1 that is deficient in recombination and repair and suppressible by RAD52

To understand the mechanisms involved in homologous recombination, we have performed a search for Saccharomyces cerevisiae mutants unable to carry out plasmid-to-chromosome gene conversion. For this purpose, we have developed a colony color assay in which recombination is induced by the controlled delivery of double-strand breaks (DSBs). Recombination occurs between a chromosomal mutant ade2 allele and a second plasmid-borne ade2 allele where DSBs are introduced via the site-specific HO endonuclease. Besides isolating a number of new alleles in known rad genes, we identified a novel allele of the RFA1 gene, rfa1-44, which encodes the large subunit of the heterotrimeric yeast single-stranded DNA-binding protein RPA. Characterization of rfa1-44 revealed that it is, like members of the RAD52 epistasis group, sensitive to X rays, high doses of UV, and HO-induced DSBs. In addition, rfa1-44 shows a reduced ability to undergo sporulation and HO-induced gene conversion. The mutation was mapped to a single-base substitution resulting in an aspartate at amino acid residue 77 instead of glycine. Moreover, all radiation sensitivities and repair defects of rfa1-44 are suppressed by RAD52 in a dose-dependent manner, and one RAD52 mutant allele, rad52-34, displays nonallelic noncomplementation when crossed with rfa1-44. Presented is a model accounting for this genetic interaction in which Rfa1, in a complex with Rad52, serves to assemble other proteins of the recombination-repair machinery at the site of DSBs and other kinds of DNA damage. We believe that our findings and those of J. Smith and R. Rothstein (Mol. Cell. Biol. 15:1632-1641, 1995) are the first in vivo demonstrations of the involvement of a eukaryotic single-stranded binding protein in recombination and repair processes.     

Improving accessibility of Web interfaces: refactoring to the rescue

Universal access should be a target for all public Web sites. However, it is very hard to achieve, and even Web applications that comply with accessibility standards may still lack usability for disabled users. This paper proposes refactoring as an essencial technique to incrementally improve the accessibility and usability of a Web interface. Some accessibility refactorings are described and classified by the problems that each refactoring addresses. The way mainstream Web sites struggle with accessibility is illustrated, and two evaluations of email clients are presented as empirical evidence of the significance of accessibility refactorings at a low implementation cost.     

食用核苷酸

<正> 以前,人们认为核苷酸并非人体所需的营养物质。人们普遍认为生物,包括人类在内,有能力在体内合成对于正常生长和发育所需的核苷酸。如今这个观点发生了改变。有证据表明食用核苷酸对人体起着至关重要的作用。核苷酸是一种低分子量的生物化合物,它几乎在所有的生化反应中部起着非常重要的作用。核苷酸由嘌呤或嘧啶(一种含氮碱基)组成。它们是组成脱氧核糖核酸和核糖核酸的基本物质,在细胞运动和新陈代谢过程中起着很多重要的作用,尤其在许多辅酶中它们也是ATP和其它核苷三磷酸的组成成分。     

Engaging end-user driven recommender systems: personalization through web augmentation

Multimedia Tools and Applications - In the past decades recommender systems have become a powerful tool to improve personalization on the Web. Yet, many popular websites lack such functionality,...     

Studies of the interaction between Rad52 protein and the yeast single-stranded DNA binding protein RPA

The RFA1 gene encodes the large subunit of the yeast trimeric single-stranded DNA binding protein replication protein A (RPA), which is known to play a critical role in DNA replication. A Saccharomyces cerevisiae strain carrying the rfa1-44 allele displays a number of impaired recombination and repair phenotypes, all of which are suppressible by overexpression of RAD52. We demonstrate that a rad52 mutation is epistatic to the rfa1-44 mutation, placing RFA1 and RAD52 in the same genetic pathway. Furthermore, two-hybrid analysis indicates the existence of interactions between Rad52 and all three subunits of RPA. The nature of this Rad52-RPA interaction was further explored by using two different mutant alleles of rad52. Both mutations lie in the amino terminus of Rad52, a region previously defined as being responsible for its DNA binding ability (U. H. Mortenson, C. Beudixen, I. Sunjeuaric, and R. Rothstein, Proc. Natl. Acad. Sci. USA 93:10729-10734, 1996). The yeast two-hybrid system was used to monitor the protein-protein interactions of the mutant Rad52 proteins. Both of the mutant proteins are capable of self-interaction but are unable to interact with Rad51. The mutant proteins also lack the ability to interact with the large subunit of RPA, Rfa1. Interestingly, they retain their ability to interact with the medium-sized subunit, Rfa2. Given the location of the mutations in the DNA binding domain of Rad52, a model incorporating the role of DNA in the protein-protein interactions involved in the repair of DNA double-strand breaks is presented.     

Distributed Web browsing: supporting frequent uses and opportunistic requirements

Universal Access in the Information Society - Nowadays, the development of Web applications supporting distributed user interfaces (DUI) is straightforward. However, it is still hard to find Web...     

Consistency of a Shared Versioned Model for Distributed Cooperation

Abstract:   In the A/E/C planning process, expert teams of different disciplines create solutions that are interdependent to a high degree. As a rule the ultimate solution needs many iteration steps. Available CAD-systems support synchronous and distributed work on a document base. Therefore, cooperation between the engineers can be obtained only by the exchange of documents. It is generally known that an overall consistency of the planning material is not adequately addressed by this approach. In this article a solution approach focused upon consistency of the shared planning material in a distributed CAD environment is presented. Because of the nature of the planning process, version management is applied on an object basis. Project data are stored as object versions and relationships. The operations for the distributed cooperation are identified and their impact on the project data is described formally, using logical expressions and set theory. A formulation based upon an algebra of sets is presented.