Surveys range from involved to simple; some are well-done, while others are poorly-constructed. One thing is certain... depending on your own immediate objectives, the complexity of the survey will vary. But what of the quality? If you foresee any possibility of employing a survey, you may wish to consider the following information about the construction of survey instruments.

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Cell lines are often used in place of primary cells to study biological processes. However, care must be taken when interpreting the results as cell lines do not always accurately replicate the primary cells. In this article, we will briefly talk about advantages and disadvantages of cell lines and then discuss results using the mouse Sertoli cell line, MSC-1, compared with primary mouse Sertoli cells. MSC-1 cells resemble Sertoli cells morphologically and possess several biochemical markers associated with Sertoli cells. Studies have demonstrated that the function and regulation of retinoic acid receptor a (RARa)is similar between MSC-1 and rat Sertoli cells. However, MSC-1 cells lack some of the immune privilege properties associated with primary Sertoli cells, including survival in animals with a fully functional immune system. Therefore, it has to be kept in mind that cell lines do not behave identically with primary cells and should not be used to replace primary cells. In order to strengthen the findings, key control experiments using primary cells should always be performed. Immortal cell

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Systems for inducing concept descriptions from examples are valuable tools for assisting in the task of knowledge acquisition for expert systems. This paper presents a description and empirical evaluation of a new induction system, cn2, designed for the efficient induction of simple

-ristic collaborative filtering (CF) and a model-based CF ap-proach. Results show that probabilistic classifiers based on temporal behavior of users have better performance than traditional recommendation-based strategies, thus reflecting that temporal information is a valuable source for the iden

Although malignant melanoma is not the most frequent cancer, its incidence is increasing faster than any other. It is considered to be the most se-rious of skin cancers because it has a potential for metastasis which explains why melanoma is re-sponsible for 90 % of all skin cancer-related deaths. According to the national tumour registry there are approximately 1500 new cases of melanoma per year in Switzerland. Early diagnosis of melanoma is particularly important because if the diagnosis is made at an early stage, meaning that the tumour thickness is less than 1 mm, the prognosis is excellent and the 10-year survival rate is estimated to be between 90 and 97 % [1, 2]. If the diagnosis is made at a more advanced stage the five-year survival rate drops to 10–15%. A further important point is that melanoma is a skin cancer that in almost 100 % of cases is localized to the skin and is therefore de-tectable by simple examination. For these two rea-sons early diagnosis of melanoma is important. Although malignant melanoma is not the most frequent cancer, its incidence is increasing faster than any other. Early diagnosis of melanoma is par-ticularly important because if the diagnosis is made at an early stage when the tumour thickness is less than 1 mm the prognosis is excellent. Dermoscopy is an in vivo method for the early diagnosis of melanoma and the differential diagnosis of pig-mented lesions of the skin. It has been shown to increase diagnostic accuracy over clinical visual in-spection in the hands of experienced physicians. This paper reviews the principles of dermoscopy, diagnostic strategies and recent technological de-velopments. Key words: dermoscopy; malignant melanoma; pigmented lesions

philosophers can serve as valuable pedagogical tools for teaching philosophy— independently of whether one believes surveying laypersons is an illuminating approach to doing philosophy. Giving students surveys that contain questions and thought experiments from philosophical debates gets them to actively