Multidimensional Evaluation of Managed Relocation Richardson, David M.; Hellmann, Jessica J.; McLachlan, Jason S. ...
Proceedings of the National Academy of Sciences - PNAS,
06/2009, Letnik:
106, Številka:
24
Journal Article
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Managed relocation (MR) has rapidly emerged as a potential intervention strategy in the toolbox of biodiversity management under climate change. Previous authors have suggested that MR (also referred ...to as assisted colonization, assisted migration, or assisted translocation) could be a last-alternative option after interrogating a linear decision tree. We argue that numerous interacting and value-laden considerations demand a more inclusive strategy for evaluating MR. The pace of modern climate change demands decision making with imperfect information, and tools that elucidate this uncertainty and integrate scientific information and social values are urgently needed. We present a heuristic tool that incorporates both ecological and social criteria in a multidimensional decision-making framework. For visualization purposes, we collapse these criteria into 4 classes that can be depicted in graphical 2-D space. This framework offers a pragmatic approach for summarizing key dimensions of MR: capturing uncertainty in the evaluation criteria, creating transparency in the evaluation process, and recognizing the inherent tradeoffs that different stakeholders bring to evaluation of MR and its alternatives.
The neuron-astrocyte synaptic complex is a fundamental operational unit of the nervous system. Astroglia regulate synaptic glutamate, via neurotransmitter transport by GLT1/EAAT2. Astroglial ...mechanisms underlying this essential neuron-glial communication are not known. We now show that presynaptic terminals regulate astroglial synaptic functions, GLT1/EAAT2, via kappa B-motif binding phosphoprotein (KBBP), the mouse homolog of human heterogeneous nuclear ribonucleoprotein K (hnRNP K), which binds the GLT1/EAAT2 promoter. Neuron-stimulated KBBP is required for GLT1/EAAT2 transcriptional activation and is responsible for astroglial alterations in neural injury. Denervation of neuron-astrocyte signaling by corticospinal tract transection, ricin-induced motor neuron death, or neurodegeneration in amyotrophic lateral sclerosis all result in reduced astroglial KBBP expression and transcriptional dysfunction of astroglial transporter expression. Presynaptic elements dynamically coordinate normal astroglial function and also provide a fundamental signaling mechanism by which altered neuronal function and injury leads to dysregulated astroglia in CNS disease.
Managed relocation is defined as the movement of species, populations, or genotypes to places outside the areas of their historical distributions to maintain biological diversity or ecosystem ...functioning with changing climate. It has been claimed that a major extinction event is under way and that climate change is increasing its severity. Projections indicating that climate change may drive substantial losses of biodiversity have compelled some scientists to suggest that traditional management strategies are insufficient. The managed relocation of species is a controversial management response to climate change. The published literature has emphasized biological concerns over difficult ethical, legal, and policy issues. Furthermore, ongoing managed relocation actions lack scientific and societal engagement. Our interdisciplinary team considered ethics, law, policy, ecology, and natural resources management in order to identify the key issues of managed relocation relevant for developing sound policies that support decisions for resource management. We recommend that government agencies develop and adopt best practices for managed relocation.
Previous studies have shown that heterologous viral infections have a significant impact on pre-existing memory T cell populations in secondary lymphoid organs through a combination of cross-reactive ...and bystander effects. However, the impact of heterologous viral infections on effector/memory T cells in peripheral sites is not well understood. In this study, we have analyzed the impact of a heterologous influenza virus infection on Sendai virus-specific CD8(+) effector/memory cells present in the lung airways. The data show a transient increase in the numbers of Sendai virus nucleoprotein 324-332/K(b)-specific CD8(+) memory T cells in the airways of the influenza-infected mice peaking around day 4 postinfection. Intratracheal transfer studies and 5-bromo-2'-deoxyuridine incorporation demonstrate that this increase is due to the recruitment of resting memory cells into the airways. In addition, the data show that these immigrating memory cells are phenotypically distinct from the resident memory T cells of the lung airways. A similar influx of nonproliferating Sendai virus nucleoprotein 324-332/K(b)-specific CD8(+) memory T cells is also induced by a secondary (homologous) infection with Sendai virus. Together, these data suggest that inflammation can accelerate memory T cell migration to nonlymphoid tissues and is a part of the normal recall response during respiratory infections.
Plant-parasitic nematodes wreak havoc on the yield and quality of crops worldwide. Damage from these pests is estimated to exceed US$100 billion annually but is likely higher due to misdiagnosis. ...Nematode damage may be catastrophic, but historically the solution has been damaging as well. Use of the synthetic nematicide methyl bromide (MBr) poses risks to the environment and to human health. Biofumigation, the use of plant material and naturally produced compounds to control pests, is an increasingly feasible method of pest management. The process acts through the growth or incorporation of plant material into the soil, that, over the course of its degradation, releases glucosinolates that break down into nematotoxic isothiocyanates. These secondary plant metabolites exist naturally in commonly grown plants, most of which belong to the Brassicaceae family. Research endeavors have increasingly explored the potential of biofumigation. The reaction of target pests, the selection of biofumigant, and ideal environments for efficacy continue to be evaluated. This review seeks to provide a cost and benefit assessment of the status of biofumigation for the control of plant-parasitic nematodes as an alternative to conventional methyl bromide usage.
Recent studies have shown that virus-specific effector memory T cells can be recovered from the lung airways long after clearance of a respiratory virus infection. These cells are thought to play an ...important role in the recall response to secondary viral infection. It is currently unclear whether these cells actually persist at this site or are maintained by continual proliferation and recruitment. In this study, we have analyzed the mechanisms underlying the persistence of memory CD8(+) T cells in the lung airway lumina following recovery from a respiratory virus infection. The data identify two distinct populations of memory cells. First, a large population Ag-specific CD8(+) T cells is deposited in the airways during the acute response to the virus. These cells persist in a functional state for several weeks with minimal further division. Second, a smaller population of Ag-specific CD8(+) T cells is maintained in the lung airways by homeostatic proliferation and migration to lung airways after viral clearance. This rate of proliferation is identical to that observed in the spleen, suggesting that these cells may be recent immigrants from the lymphoid organs. These data have significant implications for vaccines designed to promote cellular immunity at mucosal sites such as the lung.
Abstract
Despite striking global change, management to ensure healthy landscapes and sustained natural resources has tended to set objectives on the basis of the historical range of variability in ...stationary ecosystems. Many social–ecological systems are moving into novel conditions that can result in ecological transformation. We present four foundations to enable a transition to future-oriented conservation and management that increases capacity to manage change. The foundations are to identify plausible social–ecological trajectories, to apply upstream and deliberate engagement and decision-making with stakeholders, to formulate management pathways to desired futures, and to consider a portfolio approach to manage risk and account for multiple preferences across space and time. We use the Kenai National Wildlife Refuge in Alaska as a case study to illustrate how the four foundations address common land management challenges for navigating transformation and deciding when, where, and how to resist, accept, or direct social–ecological change.
Worldwide, many species are responding to ongoing climate change with shifts in distribution, abundance, phenology, or behavior. Consequently, natural‐resource managers face increasingly urgent ...conservation questions related to biodiversity loss, expansion of invasive species, and deteriorating ecosystem services. We argue that our ability to address these questions is hampered by the lack of explicit consideration of species’ adaptive capacity (AC). AC is the ability of a species or population to cope with climatic changes and is characterized by three fundamental components: phenotypic plasticity, dispersal ability, and genetic diversity. However, few studies simultaneously address all elements; often, AC is confused with sensitivity or omitted altogether from climate‐change vulnerability assessments. Improved understanding, consistent definition, and comprehensive evaluations of AC are needed. Using classic ecological‐niche theory as an analogy, we propose a new paradigm that considers fundamental and realized AC: the former reflects aspects inherent to species, whereas the latter denotes how extrinsic factors constrain AC to what is actually expressed or observed. Through this conceptualization, we identify ecological attributes contributing to AC, outline areas of research necessary to advance understanding of AC, and provide examples demonstrating how the inclusion of AC can better inform conservation and natural‐resource management.
This qualitative study sets out to explore the experiences of secondary school students while they are learning mathematics in school. By using student stories of learning mathematics as my main data ...collection method I began to understand the view of mathematics that my students were constructing as they negotiated the complicated terrain that I know as the mathematics classroom. This method of student stories to communicate student voice was selected by me to allow the students the freedom to express themselves in a variety of comfortable, differentiated formats. My methodological approach evolved as the action research phases progressed, allowing for methodological inventiveness (Dadds and Hart 2001). This was a deliberate decision by me so that my research progress could be best served by a suitable methodological approach. The end result was a qualitative study that embraced a living theory model of action research (McNiff 2013), where practitioners can develop their own personal theories of practice (Whitehead 1999). Within this action research structure I used a narrative approach, considering narratives both as a data collection method and as a transformative phenomenon. Using the ideas of narrative research for data collection, I facilitated storytelling workshops with my students, collecting stories to inform the research interest. In this research, using narratives was also considered as a phenomenon because of their influence in allowing authors to model and re-model their experiences through their stories. I found that considering narrative as phenomenon complemented and supported a portraiture methodological stance (Lawrence-Lightfoot 2005). Narrative as a phenomenon also became apparent by the influence the student stories had on my 9 ability to understand my classroom and my subsequent teaching practice. To analyse the story data I utilised the ideas of Anderson (2011) who developed a transpersonal research method that incorporates the researcher's intuition, emotional and personal capacities into the research process. By using a multi-method approach of thematic analysis, symbolic interactionist perspective, input from colleagues and my reflexive intuition, I formed an analysis of the data that could be used to look at similarities and trends in the student stories. In addition, working with the student stories encouraged levels of empathy between the reader and the student author that transformed classroom practice and understandings. There are several ways that this thesis can contribute to practice. Firstly this research develops a pedagogical tool that encourages student voice, celebrates individuality and helps create an approachable interface between mathematics teacher and student. Secondly, it models how this way of working could be used to inform the practice of the classroom teacher by developing a deeper understanding of their students. Thirdly, the identification of particular themes is invaluable to subject department development and planning, and these themes can feed into a department and whole school ethos. Finally, it models a form of action research that encourages critical reflexive practice and utilises the knowledge, experience and intuition of the researcher with the sole purpose of improving the experiences of their students.
Antiviral memory T-cell responses in the lung Woodland, David L.; Ely, Kenneth H.; Crowe, Sherry R. ...
Microbes and Infection,
08/2002, Letnik:
4, Številka:
10
Book Review, Journal Article
Recenzirano
Recent studies have identified distinct populations of memory T cells that persist in the lungs following respiratory virus infections, and contribute to the control of secondary virus infections. ...Here we discuss the establishment, maintenance and recall of memory T cells in the lung.
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