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Substantial Range (substantial + range)
Selected AbstractsCryogen spray cooling: Effects of droplet size and spray density on heat removalLASERS IN SURGERY AND MEDICINE, Issue 2 2001Brian M. Pikkula BS Abstract Background and Objective Cryogen spray cooling (CSC) is an effective method to reduce or eliminate non-specific injury to the epidermis during laser treatment of various dermatological disorders. In previous CSC investigations, fuel injectors have been used to deliver the cryogen onto the skin surface. The objective of this study was to examine cryogen atomization and heat removal characteristics of various cryogen delivery devices. Study Design/Materials and Methods Various cryogen delivery device types including fuel injectors, atomizers, and a device currently used in clinical settings were investigated. Cryogen mass was measured at the delivery device output orifice. Cryogen droplet size profiling for various cryogen delivery devices was estimated by optically imaging the droplets in flight. Heat removal for various cryogen delivery devices was estimated over a range of spraying distances by temperature measurements in an skin phantom used in conjunction with an inverse heat conduction model. Results A substantial range of mass outputs were measured for the cryogen delivery devices while heat removal varied by less than a factor of two. Droplet profiling demonstrated differences in droplet size and spray density. Conclusions Results of this study show that variation in heat removal by different cryogen delivery devices is modest despite the relatively large difference in cryogen mass output and droplet size. A non-linear relationship between heat removal by various devices and droplet size and spray density was observed. Lasers Surg. Med. 28:103,112, 2001. © 2001 Wiley-Liss, Inc. [source] Variations in Kinship Networks Across Geographic and Social SpacePOPULATION AND DEVELOPMENT REVIEW, Issue 1 2008Michael Murphy This article analyzes variations in interaction with non-coresident adult kin based on comparable cross-national surveys conducted in 2001 in 27 countries. The two main dimensions of kin contact are considered: (1) overall levels and (2) the relative emphasis given to contacts with primary kin (parents, adult children, siblings) and secondary kin (aunts, cousins, in-laws). Age-adjusted variations in kin contact between countries are much greater than those within countries. These results do not confirm the commonly hypothesized existence of well-defined family system boundaries in Europe arising from historical factors. The similarity of patterns of countries outside Europe with European countries with which they have historical ties suggests cultural factors are important in explaining interaction with kin, whereas welfare regimes appear to have little explanatory value. Within Europe, kin contact levels are more strongly related to a north/south divide than to indicators of economic development or religiosity. The findings suggest that neither of the extreme assumptions,homogenizing pressures toward a nuclear family model or persistent well-defined groupings arising from historical contexts,can be substantiated. Rather, there is a continuum in family behaviors over a substantial range, related to a number of explanatory factors. [source] Methods for detecting age-related maculopathy: a comparison between photographic and clinical assessmentCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2000Gabriella Tikellis GradDip ABSTRACT Purpose: To examine the sensitivity, specificity and overall agreement between photographic and clinical assessment in detecting age-related maculopathy (ARM) features in the context of an epidemiological study, the Vitamin E, Cataract and Age-related Maculopathy Study (VECAT). Methods: A total of 1204 volunteers aged between 55 and 80 years of age, who were enrolled in the VECAT Study, had both slit-lamp biomicroscopy examination and fundus photos taken as part of the baseline ophthalmic examination. The Nidek 3-DX fundus camera (Nidek, Gamagori, Japan) was used to produce paired, one-framed, coloured, 15° stereoslides of the macular area at a fixed angle. An International Classification and Grading System for Age-related Maculopathy and Age-related Macular Degeneration was used to grade the stereoslides. Agreement in the detection of drusen, pigment abnormalities, and late stage ARM features was assessed using unweighted kappa statistic. Cases of disagreement were verified using clinical data records, grading documentation and the review of stereoslides. Results: Macula status was available for 2386 eyes. For drusen of size < 63 ,m, sensitivity was 47%, specificity was 68% with a kappa value of 0.20. For drusen , 125 ,m, sensitivity and specificity were , 81%. Kappa values ranged from 0.56 to 0.71. Levels of agreement for pigment abnormalities and late ARM were in the substantial range (i.e. kappa values from 0.70 to 1.00). Conclusions: Slit-lamp biomicroscopy was found to be comparable to photograding (using the Nidek 3-DX fundus camera) for detecting features pertaining to ARM. However, given the objectivity and permanency of stereoslides, photograding is still the more reliable and the preferred system of assessing ARM in the context of an epidemiological study. [source] Categorical Perception and Conceptual Judgments by Nonhuman Primates: The Paleological Monkey and the Analogical ApeCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 3 2000Roger K. R. Thompson Studies of the conceptual abilities of nonhuman primates demonstrate the substantial range of these abilities as well as their limitations. Such abilities range from categorization on the basis of shared physical attributes, associative relations and functions to abstract concepts as reflected in analogical reasoning about relations between relations. The pattern of results from these studies point to a fundamental distinction between monkeys and apes in both their implicit and explicit conceptual capacities. Monkeys, but not apes, might be best regarded as "paleo-logicans" in the sense that they form common class concepts of identity on the basis of identical predicates (i.e., shared features). The discrimination of presumably more abstract relations commonly involves relatively simple procedural strategies mediated by associative processes likely shared by all mammals. There is no evidence that monkeys can perceive, let alone judge, relations-between-relations. This analogical conceptual capacity is found only in chimpanzees and humans. Interestingly, the "analogical ape," like the child, can make its analogical knowledge explicit only if it is first provided with a symbol system by which propositional representations can be encoded and manipulated. [source] | ||||||||||