3 research outputs found
Developing an academic library website model, a designer’s checklist, and an evaluative instrument
Purpose - The purpose of this paper is to introduce a library website model. Further, the paper discusses a designer's checklist and an evaluative instrument that were constructed based on the proposed model. Design/methodology/approach - The model was developed through a Delphi study that was participated by two panels of experts. The researcher communicated with the panel members via e-mail using two Delphi instruments designed out of two item pools that were developed based on the knowledge gained from surveying the literature, visiting the selected libraries and exploring the library websites. Then, a designers checklist and an evaluative instrument were derived from the proposed model through a series of brainstorming sessions. Findings - The proposed model consisted of altogether 140 items (60 web content elements and 80 web design features). The designers checklist comprises all 140 items, and the evaluative instrument comprises 60 content elements and 57 design features. Research limitations/implications - This study has developed an academic library website model and derived two instruments based on the proposed model. Further studies are needed to customize, particularly, the web content pillar of this conceptual model, to meet the specific needs of different types of libraries including public libraries, special libraries, school libraries, etc. Practical implications - The designers checklist and the evaluative instrument derived from the proposed modelare useful tools for library professionals in designing, re-designing, maintainingandevaluating their library websites. The librarians may use these tools for both institutional and research purposes. Originality/value - The model and the two instruments proposed by this study are unique in focus, origin, content and presentation
Tools to evaluate estrogenic potency of dietary phytoestrogens: A consensus paper from the eu thematic network "Phytohealth" (QLKI-2002-2453)
Phytoestrogens are naturally occurring plantderived polyphenols with estrogenic potency. They are ubiquitous in diet and therefore, generally consumed. Among Europeans, the diet is rich in multiple putative phytoestrogens including flavonoids, tannins, stilbenoids, and lignans. These compounds have been suggested to provide beneficial effects on multiple menopause-related conditions as well as on development of hormone-dependent cancers, which has increased the interest in products and foods with high phytoestrogen content. However, phytoestrogens may as well have adverse estrogenicity related effects similar to any estrogen. Therefore, the assessment of estrogenic potency of dietary compounds is of critical importance. Due to the complex nature of estrogenicity, no single comprehensive test approach is available. Instead, several in vitro and in vivo assays are applied to evaluate estrogenic potency. In vitro estrogen receptor (ER) binding assays provide information on the ability of the compound to I) interact with ERs, II) bind to estrogen responsive element on promoter of the target gene as ligand-ER complex, and III) interact between the co-activator and ERs in ligand-dependent manner. In addition, transactivation assays in cells screen for ligand-induced ERmediated gene activation. Biochemical in vitro analysis can be used to test for possible effects on protein activities and E-screen assays to measure (anti)proliferative response in estrogen responsive cells. However, for assessment of estrogenicity in organs and tissues, in vivo approaches are essential. In females, the uterotrophic assay is applicable for testing ERa agonistic and antagonistic dietary compounds in immature or adult ovariectomized animals. In addition, mammary gland targeted estrogenicity can be detected as stimulated ductal elongation and altered formation of terminal end buds in immature or peripubertal animals. In males, Hershberger assay in peri-pubertal castrated rats can be used to detect (anti)androgenic/ (anti)estrogenic responses in accessory sex glands and other hormone regulated tissues. In addition to these short-term assays, sub-acute and chronic reproductive toxicity assays as well as two-generation studies can be applied for phytoestrogens to confirm their safety in long-term use. For reliable assessment of estrogenicity of dietary phytoestrogens in vivo, special emphasis should be focused on selection of the basal diet, route and doses of administration, and possible metabolic differences between the species used and humans. In conclusion, further development and standardization of the estrogenicity test methods are needed for better interpretation of both the potential benefits and risks of increasing consumption of phytoestrogens from diets and supplements