3,518 research outputs found

    Archaeological Investigations at the Ikirahak Site Raise Questions Concerning Taltheilei Land Use in Southern Nunavut

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    We report a new Taltheilei site-type found off the west coast of Hudson Bay in southern Nunavut. The Taltheilei is an archaeological culture that existed in the Barrenlands of the central Canadian Subarctic between 2600 and 300 years ago. Their land use strategies were tethered to the seasonal migrations of the Beverly and Qamanirjuaq caribou herds throughout tundra and forest landscapes. Tundra-based sites are typically interpreted as short-lived summer camps, but our discovery of three unique pit-house sites on the shores of Maguse Lake raises new questions concerning diversity in Taltheilei tundra land use. Architectural, faunal, lithic, and geoarchaeological data recovered from the Ikirahak site (JjKs-7) support the hypothesis that Taltheilei groups were extending their tundra stays into the fall. We report the evidence from four excavated pit-house features. Terraced platforms along the internal perimeters of these houses suggest they were designed for cold season use. The faunal assemblage is dominated by caribou remains. Higher relative frequencies of appendicular elements suggest a focus on secondary butchering. A large fraction of the faunal assemblage is highly fragmented and calcined, which is consistent with heavy processing and the use of bone as an alternative fuel source. Higher frequencies of lithic debris around dwelling floor perimeters are suggestive of maintenance activities. Multi-element concentrations in dwelling and site-wide sediments also show that hearth refuse was dumped outside. These findings seem to reflect longer tundra occupations during fall, a land use strategy that was likely guided by Qamanirjuaq herd behaviour specific to the Maguse Lake area, fall hunting and processing goals, and ecologically couched mobility logistics. As just four pit-houses from one Taltheilei camp have been investigated to date, our understanding of these places within Taltheilei worlds and northern socio-ecologies is currently limited. Further research at Ikirahak, the other Maguse Lake pit-house sites, and at other caribou water crossings on the tundra of the Qamanirjuaq caribou range is needed to support or refute our hypotheses.Nous signalons un nouveau site de type taltheilei trouvé sur la côte ouest de la baie d’Hudson, dans le sud du Nunavut. La culture taltheilei est une culture archéologique qui a existé dans les landes de la zone subarctique centrale canadienne il y a de cela 2600 à 300 ans. Les stratégies d’utilisation des terres de cette culture étaient rattachées aux migrations saisonnières des hardes de caribous de Beverly et de Qamanirjuaq dans la toundra et la forêt. De manière générale, les sites trouvés dans la toundra sont interprétés comme des campements d’été de courte durée. Cependant, notre découverte de trois sites uniques de maisons semi-souterraines sur les rives du lac Maguse soulève de nouvelles questions au sujet de la diversité de l’utilisation de la toundra par les Taltheilei. Les données architecturales, fauniques, lithiques et géoarchéologiques recueillies au site d’Ikirahak soutiennent l’hypothèse selon laquelle les groupements de Taltheilei occupaient la toundra jusqu’à l’automne. Nous signalons des preuves en provenance de quatre aménagements de maisons semi-souterraines. Le long du périmètre interne de ces maisons, les plateformes en terrasses suggèrent qu’elles étaient conçues pour servir pendant la saison froide. Des restes de caribous dominent l’assemblage faunique. Des fréquences relatives plus élevées d’éléments appendiculaires laissent entrevoir que le dépeçage secondaire y occupait une grande place. Une grande fraction de l’assemblage faunique est fortement fragmentée et calcinée, ce qui correspond à une transformation importante et à l’utilisation des os comme source de combustible. Les grandes fréquences de débris lithiques entourant le périmètre des planchers d’habitations suggèrent des activités de maintenance. Les concentrations d’éléments multiples dans les sédiments des habitations et de l’ensemble du site indiquent également que les déchets des âtres étaient jetés à l’extérieur. Ces constatations laissent entrevoir de plus longues occupations de la toundra à l’automne, une stratégie d’utilisation des terres vraisemblablement guidée par le comportement propre à la harde de Qamanirjuaq dans la région du lac Maguse, par la chasse automnale et par les objectifs de transformation, de même que par la logistique de la mobilité en termes écologiques. Puisque seulement quatre maisons semi-souterraines d’un seul campement taltheilei ont été étudiées jusqu’à maintenant, nous comprenons toujours peu de choses au sujet de ces endroits dans le monde des Taltheilei et des socioécologies nordiques. Il y a lieu de pousser les recherches plus loin à Ikirahak, là où se trouvent les autres sites de maisons semi-souterraines du lac Maguse, ainsi qu’à d’autres passages de franchissement de l’eau sur la toundra du parcours des caribous de Qamanirjuaq afin de confirmer ou de réfuter nos hypothèses

    Coastal Marine Science for Law and Business Students: Preparing Law and Business Professionals to Make Informed Decisions About Coastal Issues

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    The rigors of employment-directed undergraduate education. and decreased emphasis on Liberal Arts studies occurring at some colleges and universities has left many graduates with a level of scientific understanding which is inadequate to make infonned choices about issues which effect the environment. To address this lack of scientific understanding. the Chesapeake Bay National Estuarine Research Reserve (Virginia) and the Virginia Institute of Marine Science, with the Marshall-Wythe School of Law and the School of Business Administration of the College of William and Mary are developing a Coastal Ecosystem Science Program to teach future law and business professionals the basics of coastal marine science. The Program is being developed after front-end evaluation (telephone survey of law/business faculty members from schools, law and business graduate students and industry professionals from around the United States) which explored the need, successful format, length and other essential or logistical elements of program design. Formative evaluation will continue through student pre-, and post-, testing to evaluate content, information transfer and retention. This program teaches the basic principles of coastal. environmental science to all law and business students (not just those students with experience in environmental science). The goal of this program is to ensure that future lawyers and business leaders will be able to make informed decisions about issues which effect the coastal environment. The development of the program, initial survey and focus group results, essential elements of the program design, evaluation of pilot presentations and plans for pilot-year testing in schools across the country will be discussed

    Early Epidemiological Assessment of the Virulence of Emerging Infectious Diseases: A Case Study of an Influenza Pandemic

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    Background: The case fatality ratio (CFR), the ratio of deaths from an infectious disease to the number of cases, provides an assessment of virulence. Calculation of the ratio of the cumulative number of deaths to cases during the course of an epidemic tends to result in a biased CFR. The present study develops a simple method to obtain an unbiased estimate of confirmed CFR (cCFR), using only the confirmed cases as the denominator, at an early stage of epidemic, even when there have been only a few deaths. Methodology/Principal Findings: Our method adjusts the biased cCFR by a factor of underestimation which is informed by the time from symptom onset to death. We first examine the approach by analyzing an outbreak of severe acute respiratory syndrome in Hong Kong (2003) with known unbiased cCFR estimate, and then investigate published epidemiological datasets of novel swine-origin influenza A (H1N1) virus infection in the USA and Canada (2009). Because observation of a few deaths alone does not permit estimating the distribution of the time from onset to death, the uncertainty is addressed by means of sensitivity analysis. The maximum likelihood estimate of the unbiased cCFR for influenza may lie in the range of 0.16-4.48% within the assumed parameter space for a factor of underestimation. The estimates for influenza suggest that the virulence is comparable to the early estimate in Mexico. Even when there have been no deaths, our model permits estimating a conservative upper bound of the cCFR. Conclusions: Although one has to keep in mind that the cCFR for an entire population is vulnerable to its variations among sub-populations and underdiagnosis, our method is useful for assessing virulence at the early stage of an epidemic and for informing policy makers and the public. © 2009 Nishiura et al.published_or_final_versio

    Defining biodiverse reforestation: Why it matters for climate change mitigation and biodiversity

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    Mixed species plantings present an attractive alternative to monoculture reforestation through their added benefits to biodiversity. Yet there is ambiguity in the use of the term ‘biodiversity’ in carbon and biodiversity markets, which may create perverse outcomes when designing schemes and projects. Here, we review how the concept of biodiversity is defined and applied in reforestation projects, and restoration more broadly. Improved transparency around the use of the term biodiversity is urgently needed to provide rigour in emerging market mechanisms, which seek to benefit the environment and people. Summary: Reforestation to capture and store atmospheric carbon is increasingly championed as a climate change mitigation policy response. Reforestation plantings have the potential to provide conservation co-benefits when diverse mixtures of native species are planted, and there are growing attempts to monetise biodiversity benefits from carbon reforestation projects, particularly within emerging carbon markets. But what is meant by ‘biodiverse’ across different stakeholders and groups implementing and overseeing these projects and how do these perceptions compare with long-standing scientific definitions? Here, we discuss approaches to, and definitions of, biodiversity in the context of reforestation for carbon sequestration. Our aim is to review how the concept of biodiversity is defined and applied among stakeholders (e.g., governments, carbon certifiers and farmers) and rights holders (i.e., First Nations people) engaging in reforestation, and to identify best-practice methods for restoring biodiversity in these projects. We find that some stakeholders have a vague understanding of diversity across varying levels of biological organisation (genes to ecosystems). While most understand that biodiversity underpins ecosystem functions and services, many stakeholders may not appreciate the difficulties of restoring biodiversity akin to reference ecosystems. Consequently, biodiversity goals are rarely explicit, and project goals may never be achieved because the levels of restored biodiversity are inadequate to support functional ecosystems and desired ecosystem services. We suggest there is significant value in integrating biodiversity objectives into reforestation projects and setting specific restoration goals with transparent reporting outcomes will pave the way for ensuring reforestation projects have meaningful outcomes for biodiversity, and legitimate incentive payments for biodiversity and natural capital accounting

    Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

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    A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

    Online Health Check for Reducing Alcohol Intake among Employees:A Feasibility Study in Six Workplaces across England

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    BACKGROUND: Most hazardous and harmful drinkers are of working age and do not seek help with their drinking. Occupational health services are uniquely placed to universally screen employees across the range of socioeconomic and ethnic groups. The aim was to explore the feasibility and acceptability of offering electronic screening and brief intervention for alcohol misuse in the context of a health check in six different workplace settings.  METHODS AND FINDINGS: Employees were recruited from six workplaces across England, including three local authorities, one university, one hospital and one petro-chemical company. A total of 1,254 (8%) employees completed the health check and received personalised feedback on their alcohol intake, alongside feedback on smoking, fruit and vegetable consumption and physical activity. Most participants were female (65%) and of 'White British' ethnicity (94%), with a mean age of 43 years (SD 11). Participants were mostly in Intermediate occupations (58%), followed by Higher managerial / professional (39%) and Routine and manual occupations (2%). A quarter of participants (25%) were drinking at hazardous levels (33% male, 21% female), which decreased with age. Sixty-four percent (n=797) of participants completed online follow-up at three months. Most participants were supportive of workplaces offering employees an online health check (95%), their preferred format was online (91%) and many were confident of the confidentiality of their responses (60%). Whilst the feedback reminded most participants of things they already knew (75%), some were reportedly motivated to change their behaviour (13%).  CONCLUSIONS: Online health screening and personalised feedback appears feasible and acceptable, but challenges include low participation rates, potentially attracting 'worried well' employees rather than those at greatest health risk, and less acceptance of the approach among older employees and those from ethnic minority backgrounds and routine or manual occupations

    Combined search for the quarks of a sequential fourth generation

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    Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Z/gamma* + b-jet cross section in pp collisions at 7 TeV

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    The production of b jets in association with a Z/gamma* boson is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV and recorded by the CMS detector. The inclusive cross section for Z/gamma* + b-jet production is measured in a sample corresponding to an integrated luminosity of 2.2 inverse femtobarns. The Z/gamma* + b-jet cross section with Z/gamma* to ll (where ll = ee or mu mu) for events with the invariant mass 60 < M(ll) < 120 GeV, at least one b jet at the hadron level with pT > 25 GeV and abs(eta) < 2.1, and a separation between the leptons and the jets of Delta R > 0.5 is found to be 5.84 +/- 0.08 (stat.) +/- 0.72 (syst.) +(0.25)/-(0.55) (theory) pb. The kinematic properties of the events are also studied and found to be in agreement with the predictions made by the MadGraph event generator with the parton shower and the hadronisation performed by PYTHIA.Comment: Submitted to the Journal of High Energy Physic

    Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

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    A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

    Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV

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    The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/- 2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction of the standard model.Comment: Replaced with published version. Included journal reference and DO
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