603 research outputs found

    Evaluation and improvement of model algorithms for predicting belowground carbon allocation in forests

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    Rapidly rising concentrations of atmospheric carbon dioxide (CO 2) influence forest productivity by stimulating plant growth. It can also modify carbon partitioning patterns, altering the global carbon cycle. Nitrogen and carbon cycles are tightly linked; with changes in nitrogen availability affecting ecosystem carbon allocation by shifting carbon to roots for nitrogen uptake. This paper discusses a modification to the PnET-CN model (Aber et al. 1997) developed to shift plant carbon allocation belowground in response to nitrogen limitation. According to functional equilibrium models of plant carbon allocation, a nitrogen control mechanism alters belowground carbon estimates by increasing carbon allocation to fine roots when nitrogen resources are low. Testing of the modified mechanism with data from three free-air CO 2 enrichment (FACE) forests supported the mechanism by allocating more carbon to fine roots. Application of the model with data from five northeastern forests, under a variety of global climate change scenarios, also supported the modified mechanism with an increase in soil carbon storage

    Adverse Moisture Events Predict Seasonal Abundance of Lyme Disease Vector Ticks (\u3cem\u3eIxodes scapularis\u3c/em\u3e)

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    Background Lyme borreliosis (LB) is the most commonly reported vector-borne disease in north temperate regions worldwide, affecting an estimated 300,000 people annually in the United States alone. The incidence of LB is correlated with human exposure to its vector, the blacklegged tick (Ixodes scapularis). To date, attempts to model tick encounter risk based on environmental parameters have been equivocal. Previous studies have not considered (1) the differences between relative humidity (RH) in leaf litter and at weather stations, (2) the RH threshold that affects nymphal blacklegged tick survival, and (3) the time required below the threshold to induce mortality. We clarify the association between environmental moisture and tick survival by presenting a significant relationship between the total number of tick adverse moisture events (TAMEs - calculated as microclimatic periods below a RH threshold) and tick abundance each year. Methods We used a 14-year continuous statewide tick surveillance database and corresponding weather data from Rhode Island (RI), USA, to assess the effects of TAMEs on nymphal populations of I. scapularis. These TAMEs were defined as extended periods of time (\u3e8 h below 82% RH in leaf litter). We fit a sigmoid curve comparing weather station data to those collected by loggers placed in tick habitats to estimate RH experienced by nymphal ticks, and compiled the number of historical TAMEs during the 14-year record. Results The total number of TAMEs in June of each year was negatively related to total seasonal nymphal tick densities, suggesting that sub-threshold humidity episodes \u3e8 h in duration naturally lowered nymphal blacklegged tick abundance. Furthermore, TAMEs were positively related to the ratio of tick abundance early in the season when compared to late season, suggesting that lower than average tick abundance for a given year resulted from tick mortality and not from other factors. Conclusions Our results clarify the mechanism by which environmental moisture affects blacklegged tick populations, and offers the possibility to more accurately predict tick abundance and human LB incidence. We describe a method to forecast LB risk in endemic regions and identify the predictive role of microclimatic moisture conditions on tick encounter risk

    Teaching with Feminist Judgments: A Global Conversation

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    This conversational-style essay is an exchange among fourteen professors—representing thirteen universities across five countries—with experience teaching with feminist judgments. Feminist judgments are ‘shadow’ court decisions rewritten from a feminist perspective, using only the precedent in effect and the facts known at the time of the original decision. Scholars in Canada, England, the U.S., Australia, New Zealand, Scotland, Ireland, India, and Mexico have published (or are currently producing) written collections of feminist judgments that demonstrate how feminist perspectives could have changed the legal reasoning or outcome (or both) in important legal cases. This essay begins to explore the vast pedagogical potential of feminist judgments. The contributors to this conversation describe how they use feminist judgments in the classroom; how students have responded to the judgments; how the professors achieve specific learning objectives through teaching with feminist judgments; and how working with feminist judgments—whether studying them, writing them, or both—can help students excavate the multiple social, political, economic, and even personal factors that influence the development of legal rules, structures, and institutions. The primary takeaway of the essay is that feminist judgments are a uniquely enriching pedagogical tool that can broaden the learning experience. Feminist judgments invite future lawyers, and indeed any reader, to re-imagine what the law is, what the law can be, and how to make the law more responsive to the needs of all people

    Interaction of glycoprotein H of human herpesvirus 6 with the cellular receptor CD46.

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    Human herpesvirus 6 (HHV-6) employs the complement regulator CD46 (membrane cofactor protein) as a receptor for fusion and entry into target cells. Like other known herpesviruses, HHV-6 encodes multiple glycoproteins, several of which have been implicated in the entry process. In this report, we present evidence that glycoprotein H (gH) is the viral component responsible for binding to CD46. Antibodies to CD46 co-immunoprecipitated an approximately 110-kDa protein band specifically associated with HHV-6-infected cells. This protein was identified as gH by selective depletion with an anti-gH monoclonal antibody, as well as by immunoblot analysis with a rabbit hyperimmune serum directed against a gH synthetic peptide. In reciprocal experiments, a monoclonal antibody against HHV-6 gH was found to co-immunoprecipitate CD46. Studies using monoclonal antibodies directed against specific CD46 domains, as well as engineered constructs lacking defined CD46 regions, demonstrated a close correspondence between the CD46 domains involved in the interaction with gH and those previously shown to be critical for HHV-6 fusion (i.e. short consensus repeats 2 and 3)

    ‘Super disabilities’ vs ‘Disabilities’?:Theorizing the role of ableism in (mis)representational mythology of disability in the marketplace

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    People with disabilities (PWD) constitute one of the largest minority groups with one in five people worldwide having a disability. While recognition and inclusion of this group in the marketplace has seen improvement, the effects of (mis)representation of PWD in shaping the discourse on fostering marketplace inclusion of socially marginalized consumers remain little understood. Although effects of misrepresentation (e.g., idealized, exoticized or selective representation) on inclusion/exclusion perceptions and cognitions has received attention in the context of ethnic/racial groups, the world of disability has been largely neglected. By extending the theory of ableism into the context of PWD representation and applying it to the analysis of the We’re the Superhumans advertisement developed for the Rio 2016 Paralympic Games, this paper examines the relationship between the (mis)representation and the inclusion/exclusion discourse. By uncovering that PWD misrepresentations can partially mask and/or redress the root causes of exclusion experienced by PWD in their lived realities, it contributes to the research agenda on the transformative role of consumption cultures perpetuating harmful, exclusionary social perceptions of marginalized groups versus contributing to advancement of their inclusion

    Diversity among Equals: Educational Opportunity and the State of Affirmative Admissions in New England

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    This report reviews the practice of Affirmative Admissions as a strategy for achieving diversity within New England colleges and universities. It shows how educational leaders perceive Affirmative Admissions, the nature of regional Affirmative Admissions policies, and the numbers of student affected by current enrollment strategies. This report is part of a larger series on educational access and opportunity in New England. Research was organized into five components: (1) analysis of pertinent legal issues related to postsecondary access and equity; (2) interviews with postsecondary campus and state leaders (n=104); (3) interviews with K-12 leaders and educators at state, district, and school levels (n=45); (4) a survey of 221 postsecondary education institutions in New England; and (5) econometric analyses of student data. The focus was on groups of institutions, 18 groups clustered by admissions policies and restrictions. The most compelling conclusion is that there is no significant evidence that colleges have reduced standards to admit greater numbers of minority students. By increasing educational access to a broader segment of the population, the regions higher education institutions have taken crucial steps toward assuring the vitality and vibrancy of New Englands future economy and civic life. The study also indicates that the pool of qualified minority students is much too small, highlighting the need to improve the preparation of minority students. Three appendixes contain details about survey methodology, participating institutions, and regression coefficients. Prepared by the Center for Education Policy (CEP) and Massachusetts Institute for Social and Economic Research (MISER), University of Massachusetts at Amherst. Sponsored by the Nellie Mae Education Foundation

    San Giovanni Laterano Studio Project, Syracuse University School of Architecture Florence Program (1983)

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    This publication is the result of one semester\u27s design work from the Syracuse University Florence Program. Our purpose in compiling this material is two-fold; in presenting this work as an example of the design activity that occurs at the Florence Center, we intend to reveal the unique opportunity that this Program offers to students from the United States. In addition, we are using this vehicle to address the in­tellectual context within which our students worked during their design process. Giuseppe Vallifuoco and Sergio Petrini (Roman architects and our Visiting Critics) presented a specific bias toward the produc­tion of architecture, and we feel that an explication of their concerns can contribute to an understanding of current architectural activity in Italy
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