New Distribution Records for Mosquitoes in Michigan (Diptera: Culicidae)

(excerpt) Since the late 1940\u27s very little information has appeared in the literature dealing with the geographical distribution of mosquitoes in Michigan. The earliest attempt at establish- ing a comprehensive list of species was made by Irwin (1941) who catalogued 43 species by county. A survey by Pederson (1947) resulted in the collection of 48 species and provided the most extensive distribution list of mosquitoes in Michigan. Recent studies by Newson et al. (1975), McGroarty et al. (1976) and Grimstad (1977) have contributed several new distribution and state records. Prompted by the 1975 St. Louis encephalitis outbreak in Michigan, and a lack of current information on the species of mosquitoes in Isabella County, a survey of mosquitoes was conducted in the Mount Pleasant area

Effects of Light Attenuation on Local and Bulk Mechanical Properties of Photopolymerized PEG Hydrogels

Cell experiments investigating cell behavior as a function of material stiffness are often carried out on the surface of hydrogels. An assumption that the bulk hydrogel mechanical properties represent the surface properties is often employed but in many cases is not valid. In photo-initiated radical polymerization, photons are absorbed by initiator chromophores generating high energy electrons. As photons progress through the prepolymer solution, the intensity of light that reaches the distal end of the solution is decreased through this attenuation. This work aims to determine whether light attenuation plays a significant role in local stiffness within a poly(ethylene glycol) diacrylate (PEGDA) hydrogel, compared to its bulk stiffness. Differences in bulk properties were tested by varying the polymerization parameters of hydrogel cylindrical plugs, including sample thickness (0.7mm – 1.2mm), photoinitiator type (EosinY vs LAP), PEGDA weight percent, and exposure time. Mechanical loading data of the plugs was analyzed to reveal the relationships between the physical properties (e.g. thickness, surface area, volume) and chemical properties (e.g. monomer and initiator concentrations, exposure settings). Preliminary data suggests that an appreciable difference in physical properties exists between gels of differing thickness (1.0mm vs 0.3mm based on gel point). The goals of this work are to quantify the extent of this difference based on sample thickness, and to compare the bulk stiffness data with local surface stiffness measurements obtained using an AFM nano-indentation technique and determine whether changes in bulk properties carry over to changes in surface properties

Body fatness or anthropometry for assessment of unhealthy weight status? Comparison between methods in South African children and adolescents

A variety of methods are available for defining undernutrition (thinness/underweight/under-fat) and overnutrition (overweight/obesity/over-fat). The extent to which these definitions agree is unclear. The present cross-sectional study aimed to assess agreement between widely used methods of assessing nutritional status in children and adolescents, and to examine the benefit of body composition estimates. The main objective of the cross-sectional study was to assess underweight, overweight and obesity using four methods: (i) BMI-for-age using WHO (2007) reference data; (ii) BMI-for-age using Cole et al. and International Obesity Taskforce cut-offs; (iii) weight-for-age using the National Centre for Health Statistics/WHO growth reference 1977; and (iv) body fat percentage estimated by bio-impedance (body fat reference curves for children of McCarthy et al., 2006). Comparisons were made between methods using weighted kappa analyses. Subjects Individuals (n 1519) in three age groups (school grade 1, mean age 7 years; grade 5, mean age 11 years; grade 9, mean age 15 years). Results In boys, prevalence of unhealthy weight status (both under- and overnutrition) was much higher at all ages with body fatness measures than with simple anthropometric proxies for body fatness; agreement between fatness and weight-based measures was fair or slight using Landis and Koch categories. In girls, prevalence of unhealthy weight status was also higher with body fatness than with proxies, although agreement between measures ranged from fair to substantial. Methods for defining under- and overnutrition should not be considered equivalent. Weight-based measures provide highly conservative estimates of unhealthy weight status, possibly more conservative in boys. Simple body composition measures may be more informative than anthropometry for nutritional surveillance of children and adolescents