An overview of Polaroid sun eyewear: Function, application and market

Patients are constantly looking for the newest technologies that will assist them in accomplishing the activities that they desire more comfortably and efficiently, in both their personal and professional lives. It is our responsibility as primary care practitioners to be current with the latest advancement in ophthalmic therapies, and effectively pass this knowledge on to our patients. This paper will encompass the properties of specialty protective sun eyewear, emphasizing polarized sunglasses, and how they can be incorporated into a private practice as a viable profit center. The intent is to provide the practitioner with a general overview of the basic properties of light and the history of polarized sunglasses and the functional benefits that they may offer consumers. This review will help to enable a practitioner to feel confident and more comfortable in prescribing and recommending these specialty performance lenses to their patients

The K = 2 conundrum

Assessments of population genetic structure have become an increasing focus as they can provide valuable insight into patterns of migration and gene flow.STRUCTURE, the most highly cited of several clustering-based methods, was developed to provide robust estimates without the need for populations to be determined a priori.STRUCTURE introduces the problem of selecting the optimal number of clusters, and as a result, the ΔK method was proposed to assist in the identification of the “true” number of clusters. In our review of 1,264 studies usingSTRUCTURE to explore population subdivision, studies that used ΔK were more likely to identify K = 2 (54%, 443/822) than studies that did not use ΔK (21%, 82/386). A troubling finding was that very few studies performed the hierarchical analysis recommended by the authors of both ΔK andSTRUCTURE to fully explore population subdivision. Furthermore, extensions of earlier simulations indicate that, with a representative number of markers, ΔK frequently identifies K = 2 as the top level of hierarchical structure, even when more subpopulations are present. This review suggests that many studies may have been over-or underestimating population genetic structure; both scenarios have serious consequences, particularly with respect to conservation and management. We recommend publication standards for population structure results so that readers can assess the implications of the results given their own understanding of the species biology

Initial sequencing and analysis of the human genome

The human genome holds an extraordinary trove of information about human development, physiology, medicine and evolution. Here we report the results of an international collaboration to produce and make freely available a draft sequence of the human genome. We also present an initial analysis of the data, describing some of the insights that can be gleaned from the sequence