98 research outputs found

    Factors Affecting Six Sigma Project Selection In The Information Systems/Information Technology Arena

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    The success of Six Sigma organization-wide requires that projects be resolved in a successful fashion and that the organization realize the benefits that these projects are supposed to deliver.  The success of information systems (IS) and information technology (IT) projects depends on these projects being developed in such a way that they are deployed error free.  The two development methods are different and the result is that many IS/IT personnel do not see where or how Six Sigma can be applied to their area.   In this paper, we discuss factors that are unique to the IS/IT environment that need to be considered when selecting Six Sigma IS/IT projects so that both sets of objectives can be successfully realized

    Spring Migration of Eiders and Other Waterbirds at Point Barrow, Alaska

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    Birds migrating along the flaw lead at Point Barrow, Alaska were observed from 6 May to 4 June 1976. Little migration occurred until 25 and 26 May, when winds shifted from northeasterly to southwesterly and widened the lead. King Eiders (Somateria spectabilis) were the most abundant migrant; their movements were greatest with southwesterly (following) winds and between 1200 and 1800 h (Alaska Daylight Savings Time). On 26 May 360,000 King Eiders passed within a 10-hour period. Ninety percent of the migrant Glaucous Gulls (Larus hyperboreus) moved east by 25 May. Common Eiders (Somateria mollissima) and Oldsquaw (Clangula hyemalis) were most abundant in early June and the bulk of their migration probably occurred after 4 June. Male King Eiders passed mostly in May while females were more common in June, suggesting that this species delays pair bonding until the latter part of their migration. This strategy necessitates an early migration and introduces the risk of possible starvation due to late spring freezing in the high Arctic.Key words: waterbirds, eiders, King Eiders, Somateria spectabilis; Glaucuous Gulls, Larus hyperboreus; Common Eiders, Somateria mollissima; Oldsquaw, Clangula hyemalis; migrationMots clés: oiseaux marins, eiders, eiders respectable, Somateria spectabilis; goéland bourgmestre, Larus hyperboreus; eider commun, Somateria mollisima; canard à longue queue, Clangula hyemalis; migratio

    Arctic Cod (Boreogadus saida) as Prey: Fish Length-Energetics Relationships in the Beaufort Sea and Hudson Bay

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    Although Arctic cod (Boreogadus saida) is widely recognized as an important trophic link to top predators in Arctic marine ecosystems, the challenges of conducting fieldwork in the Arctic make this species difficult to study. We establish some basic relationships to improve prey energetics modeling when only in-field parameters (e.g., fork length) can be measured. We investigated the intraspecific relationships among energy density, fork length, mass, and water content for Arctic cod captured by Black Guillemots and Thick-billed Murres at two sites (Western Beaufort and Hudson Bay). Dry energy density was similar between sites (21.6 – 22.2 kJ g-1) and increased with fork length (Dry EDkJ/g = 0.028 (± 0.01) • Fork Lengthmm + 18.12 (± 1.33). Even though fish lost some water as they were transported to the nest by avian predators, wet energy density also increased with fork length. We suggest that environmental conditions had a similar effect on growth at these two locations although they occur in very different oceanographic regimes. Arctic cod, especially large cod, is one of the most energy-rich prey species in the Arctic. Our results highlight the importance of this valuable prey to Arctic ecosystems and the utility of using seabirds opportunistically as samplers of the marine environment.Même si la morue polaire (Boreogadus saida) est grandement reconnue comme un lien trophique important pour les prédateurs situés en bout de chaîne des écosystèmes marins de l’Arctique, cette espèce est difficile à étudier en raison des défis inhérents à la réalisation de travaux sur le terrain dans l’Arctique. Nous établissons des relations de base afin d’améliorer la modélisation de la valeur énergétique des proies lorsque seuls des paramètres sur le terrain (comme la longueur à la fourche) peuvent être mesurés. Nous avons étudié les relations intraspécifiques qui existent entre la densité d’énergie, la longueur à la fourche, la masse et la teneur en eau de la morue polaire capturée par le guillemot à miroir et le guillemot de Brünnich à deux sites (ouest de Beaufort et baie d’Hudson). La densité d’énergie sèche était semblable entre les sites (21,6 – 22,2 kJ g-1) et augmentait en fonction de la longueur à la fourche (DE sèche EDkJ/g = 0,028 (± 0,01) • longueur à la fourchemm + 18,12(± 1,33). Même si les poissons perdaient de l’eau pendant le transport jusqu’au nid par les oiseaux prédateurs, la densité d’énergie humide augmentait également en fonction de la longueur à la fourche. Nous suggérons que les conditions environnementales avaient un effet similaire sur la croissance à ces deux sites même s’ils se trouvent dans des régimes océanographiques très différents. La morue polaire, surtout celle de grande taille, est l’une des espèces proies les plus riches en énergie de l’Arctique. Nos résultats mettent en évidence l’importance de cette précieuse proie pour les écosystèmes de l’Arctique et l’utilité de se servir des oiseaux de mer de manière opportuniste en guise d’échantillonneurs de l’environnement marin

    The rate of telomere loss is related to maximum lifespan in birds

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    Telomeres are highly conserved regions of DNA that protect the ends of linear chromosomes. The loss of telomeres can signal an irreversible change to a cell's state, including cellular senescence. Senescent cells no longer divide and can damage nearby healthy cells, thus potentially placing them at the crossroads of cancer and ageing. While the epidemiology, cellular and molecular biology of telomeres are well studied, a newer field exploring telomere biology in the context of ecology and evolution is just emerging. With work to date focusing on how telomere shortening relates to individual mortality, less is known about how telomeres relate to ageing rates across species. Here, we investigated telomere length in cross-sectional samples from 19 bird species to determine how rates of telomere loss relate to interspecific variation in maximum lifespan. We found that bird species with longer lifespans lose fewer telomeric repeats each year compared with species with shorter lifespans. In addition, phylogenetic analysis revealed that the rate of telomere loss is evolutionarily conserved within bird families. This suggests that the physiological causes of telomere shortening, or the ability to maintain telomeres, are features that may be responsible for, or co-evolved with, different lifespans observed across species.This article is part of the theme issue 'Understanding diversity in telomere dynamics'

    Roles for retrotransposon insertions in human disease

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    Review: Effects of Climate Change on Birds (møller, Ap, Fiedler, W & Berthold, Pja, Eds)

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    Factors affecting the growth of a Black Guillemot colony in northern Alaska

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    Thesis (Ph.D.) University of Alaska Fairbanks, 1998Annual variation in breeding populations at seabird colonies has been well documented, but there have been few long-term attempts to examine the environmental and demographic forces responsible. I studied breeding chronology and demography Black Guillemot in northern Alaska from 1975-1997 to identify the factors responsible for colony establishment and growth. The Black Guillemot is a cavity-nesting seabird whose populations are frequently limited by nest-site availability. Snowmelt in spring and snow accumulation in autumn had major effects on annual nesting initiation and success, respectively. Annual arrival at the colony and median date of egg laying was well correlated with the date of snow disappearance, with annual clutch initiation advancing 4.5 days per decade in response to regional climate amelioration. Successful breeding requires a snowfree cavity for >80 days. Decreased breeding success and post-fledging survival occurred in a year with a snow-free period 80 days were uncommon until the 1960's, when the species was first recorded breeding in northern Alaska. When additional nest sites were provided, growth of the colony was rapid, increasing from 18 pairs in 1975 to 225 pairs in 1989. Breeding numbers then decreased to 150 in 1996 as factors other than nest-site availability controlled population size. Annual population growth averaged 37% from 1976-1982 when nest site occupancy was low, 3% from 1983-1989 when all or most nesting cavities were occupied, and -6% from 1990-1996 as breeding productivity decreased and mortality of adults increased. Without immigration and with the average annual vital rates the colony would have had an annual rate of growth of 4% during this study. Contrary to published models of seabird colony growth, I found immigration important (>60% of annual recruitment) in all phases of growth. Philopatry showed previously unreported large variation among cohorts related to variation in nest-site vacancies at the natal colony and estimated recruitment opportunities at regional colonies. Philopatry was highest (>80%) for cohorts maturing when most regional recruitment opportunities were at the study colony but low (15%) when nest-site availability was likely similar at the natal colony and other colonies in the region
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