963 resultados para History, 2000-


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Due to their maternal mode of inheritance, mitochondrial markers can be regarded as almost 'ideal' tools in evolutionary studies of conifer populations. In the present study, polymorphism was analysed at one mitochondrial intron (nad 1, exon B/C) in 23 native European Pinus sylvestris populations. In a preliminary screening for variation using a polymerase chain reaction-restriction fragment length polymorphism approach, two length variants were identified. By fully sequencing the 2.5 kb region, the observed length polymorphism was found to result from the insertion of a 31 bp sequence, with no other mutations observed within the intron. A set of primers was designed flanking the observed mutation, which identified a novel sequence-tagged-site mitochondrial marker for P. sylvestris. Analysis of 747 trees from the 23 populations using these primers revealed the occurrence of two distinct haplotypes in Europe. Within the Iberian Peninsula, the two haplotypes exhibited extensive population differentiation (Phi(ST) = 0.59; P less than or equal to 0.001) and a marked geographical structuring. In the populations of central and northern Europe, one haplotype largely predominated, with the second being found in only one individual of one population.

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Objective: To describe the incidence, prevalence, and natural history of proliferative sickle cell retinopathy (PSR). Design: Prospective longitudinal study over 20 years. Participants: Newborn screening of 100000 consecutive deliveries from 1973 to 1981 identified 315 children with homozygous sickle cell (SS) disease and 201 with SS-hemoglobin C (SC) disease. By the age of 5 years, 307 SS patients and 166 SC patients were alive and living in Jamaica and were recruited for this ophthalmic study. Methods: Description of retinal vascular changes on annual angiography and angioscopy. Main Outcome Measures: Incidence and prevalence of PSR and its behavior on follow-up. Progression of PSR was investigated using the number of eyes affected (none, one, both) and the interval until PSR onset. Results: At last review in January 2000, PSR had developed in 59 patients (14 SS, 45 SC), unilaterally in 36 patients and bilaterally in 23. Incidence increased with age in both genotypes, with crude annual incidence rates of 0.5 cases (95% confidence interval [CI], 0.3-0.8) per 100 SS subjects and 2.5 cases (95% CI, 1.9-3.3) per 100 SC subjects. Prevalence was greater in SC disease, and by the ages of 24 to 26 years, PSR had occurred in 43% subjects with SC disease and in 14% subjects with SS disease. Patients with unilateral PSR had a 16% (11% SS, 17% SC) probability of regressing to no PSR and a 14% (16% SS, 13% SC) probability of progressing to bilateral PSR. Those with bilateral PSR had an 8% (8% SS, 8% SC) probability of regressing to unilateral PSR and a 1% (0 SS, 2% SC) probability of regressing to a PSR-free state. Irretrievable visual loss occurred in only 1 of 82 PSR-affected eyes, and 1 required detachment surgery and recovered normal visual acuity. Conclusions: Longitudinal observations over 20 years in a cohort of patients followed from birth confirms a greater incidence and severity of PSR in SC disease, and shows that spontaneous regression occurred in 32% of PSR-affected eyes. Permanent visual loss was uncommon in subjects observed up to the age of 26 years. © 2005 by the American Academy of Ophthalmology.

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Aims: We investigated the physical properties and dynamical evolution of near-Earth asteroid (NEA) (190491) 2000 FJ10 in order to assess the suitability of this accessible NEA as a space mission target. Methods: Photometry and colour determination were carried out with the 1.54 m Kuiper Telescope (Mt Bigelow, USA) and the 10 m Southern African Large Telescope (SALT; Sutherland, South Africa) during the object's recent favourable apparition in 2011-12. During the earlier 2008 apparition, a spectrum of the object in the 6000-9000 Angstrom region was obtained with the 4.2 m William Herschel Telescope (WHT; Canary Islands, Spain). Interpretation of the observational results was aided by numerical simulations of 1000 dynamical clones of 2000 FJ10 up to 106 yr in the past and in the future. Results: The asteroid's spectrum and colours determined by our observations suggest a taxonomic classification within the S-complex although other classifications (V, D, E, M, P) cannot be ruled out. On this evidence, it is unlikely to be a primitive, relatively unaltered remnant from the early history of the solar system and thus a low priority target for robotic sample return. Our photometry placed a lower bound of 2 h to the asteroid's rotation period. Its absolute magnitude was estimated to be 21.54 ± 0.1 which, for a typical S-complex albedo, translates into a diameter of 130 ± 20 m. Our dynamical simulations show that it has likely been an Amor for the past 105 yr. Although currently not Earth-crossing, it will likely become so during the period 50-100 kyr in the future. It may have arrived from the inner or central main belt >1 Myr ago as a former member of a low-inclination S-class asteroid family. Its relatively slow rotation and large size make it a suitable destination for a human mission. We show that ballistic Earth-190491-Earth transfer trajectories with ΔV <2 km s-1 at the asteroid exist between 2052 and 2061. Based on observations made with the Southern African Large Telescope (SALT).

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We find that regional height levels around the world were fairly uniform throughout most of the 19th century, with two exceptions: above-average levels in Anglo-Saxon settlement regions and below-average levels in Southeast Asia. After 1880, substantial diver- gences began to differentiate other regions -- making the world population taller, but more unequal. During the late 19th century and 20th century, heights between world regions devi- ated significantly, when incomes also became very unequal. Interestingly, during the “breaking point period” between the two regimes, heights declined significantly in the cattle-rich New World countries, whereas they started to increase in Old Europe. We discuss in this study whether immigration was a core factor to influence the height decline in the “Anthropometric Decline of the Cowboy and Gaucho Empires”.

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How much does the antiquity of states, and the sometimes arbitrary nature of colonial boundaries, explain the modern degree of ethnic diversity? It is shown that states with greater historical legitimacy (more continuity between the pre-colonial and post-colonial state) have less ethnic diversity. Historical legitimacy is more strongly correlated with ethnic diversity than are the antiquity of states, genetic diversity or the duration of human settlement. Although historical legitimacy is particularly pertinent to Africa, the correlation also holds outside Africa.

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Cataloguing Kays is a university-run project intended to create a community web-archive to celebrate the history and public memory of Kay & Co Ltd of Worcester, a noted mailorder catalogue company which was, until 2006, the largest employer in Worcester. The Kays Archive, housed at UoW, is one of the most comprehensive archive collections of 20th century mail-order catalogues in the UK and has a strong local elevance. The catalogues provide a window into over 100 years of body image, social history, consumable goods, fashion and design. The Project Team created www.WorldofKays.org, an online, fully-searchable archive containing 1500 digitised images from the catalogues, 1920-2000. The website is intended to form a seed bed for international research, focussing in particular on the representation of body image and the way the catalogues represent the developing tropes of consumer lifestyle and aspiration. The images are enhanced by blog postings from or film and audio interviews with local residents and former Kays staff members, who recall how the goods were selected and presented; as well as the impact the mail-order industry had on shaping 20th century lifestyle and consumption. These interviews and blogs have been sourced through the Cataloguing Kays team’s outreach activity in the local, academic and online communities. From the outset, we, the Cataloguing Kays team, engaged with online communities through social media sites, Facebook and Twitter, and through specialist blogs and online forums, inviting comment and contributions. Through events for the general public and a programme of targeted community outreach work with Kays Heritage Group and support groups for Worcestershire’s young and adult carers, we have also collected filmed and audio reminiscence material as well as community art and poetry content for the website. Our academic conference, the Catalogue of Dreams, showcased both the website and the physical archive to the wider academic, cultural and heritage sectors, provoking lively debateand much interest from international scholars.

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Margaret was an only child who grew up on a farm just east of Cayuga, Ontario. After high school, Margaret attended Hamilton Teacher’s College and took a position with Grantham Public School Board and taught at Power Glen school. Margaret was married in 1962 and had 2 children, a daughter and a son in 1963 and 1964, respectively. Margaret left her teaching job to raise her children. Margaret was very creative and artistic and during this time, focused on these talents, which included painting, graphic arts and sewing. Margaret was also an accomplished pianist. In her 40’s, Margaret enrolled at Brock University and in 1989 obtained a Honors Bachelor of Arts degree with First-Class Honors in Sociology. In partial fulfillment of her Honors B.A. she completed her thesis that is entitled ; The State and Liberal Feminism: The Ontario Government’s “Business Ownership For Women Program”. While living in St. Catharines, Margaret attended York University and graduated with a Master of Arts in Sociology in 1992 where her studies focused on women’s issues. Margaret received a scholarship from York University and was a teaching assistant. Margaret stayed on at York University and completed her academic requirements for a Doctorate degree in Sociology. Her dissertation was on self employed women in St. Catharines at the beginning of WWII -- not the” Rosie the Riveters” who took over jobs formerly held by men who had to go off to fight World War II, but women who ran their own businesses when that was still unusual. Margaret completed the research for her thesis but did not complete her written thesis as she made a difficult decision to put her academic work on hold in the mid-1990’s and she returned to her love for the arts, although she always remained a voracious reader and interested in women’s issues. In the last decade of her life, she took up quilting with a passion, which she referred to as fabric arts. Margaret loved colour and being non-traditional. Margaret had been a quilting instructor at the Flemington College for Fine Arts in Haliburton. In 1997, Margaret founded Project Smile in the St. Catharines region, a non-profit group who make quilts for children with cancer. Margaret was also the President of the Niagara Heritage Quilters’ Guild in 2006-2007 and was very involved with the Local Council of Women.

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Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal