67 research outputs found
Improving reporting of uncertainties in sea level rise assessments
Sea level rise (SLR) assessments are commonly used to identify the extent that coastal populations are at risk to
flooding. However, the data and assumptions used to develop these assessments contain numerous sources and types
of uncertainty, which limit confidence in the accuracy of modeled results. This study illustrates how the intersection
of uncertainty in digital elevation models (DEMs) and SLR lead to a wide range of modeled outcomes. SLR
assessments are then reviewed to identify the extent that uncertainty is documented in peer-reviewed articles. The
paper concludes by discussing priorities needed to further understand SLR impacts. (PDF contains 4 pages
Knowledge Co-production in Contested Spaces: An Evaluation of the North Slope Borough – Shell Baseline Studies Program
Supporting the development of trusted and usable science remains a key challenge in contested spaces. This paper evaluates a collaborative research agreement between the North Slope Borough of Alaska and Shell Exploration and Production Company—an agreement that was designed to improve collection of information and management of issues associated with the potential impacts of oil and gas development in the Arctic. The evaluation is based on six categories of knowledge co-production indicators: external factors, inputs, processes, outputs, outcomes, and impacts. Two sources of data were used to assess the indicators: interviews with steering committee members and external science managers (n = 16) and a review of steering committee minutes. Interpretation of the output and outcome indicators suggests that the Baseline Studies Program supported a broad range of research, though there were differences in how groups perceived the relevance and legitimacy of project outcomes. Several input, process, and external variables enabled the co-production of trusted science in an emergent boundary organization and contested space; these variables included governance arrangements, leveraged capacities, and the inclusion of traditional knowledge. Challenges to knowledge co-production on the North Slope include logistics, differences in cultures and decision contexts, and balancing trade-offs among perceived credibility, legitimacy, and relevance. Reinforced lessons learned included providing time to foster trust, developing adaptive governance approaches, and building capacity among scientists to translate community concerns into research questions.La nécessité d’appuyer la production de données scientifiques fiables et utilisables demeure un défi important dans les espaces contestés. Le présent article évalue une entente de collaboration de recherche entre la municipalité de North Slope, en Alaska, et la Shell Exploration and Production Company, entente destinée à améliorer la collecte de renseignements et la gestion des enjeux liés aux incidences éventuelles de l’exploitation pétrolière et gazière dans l’Arctique. L’évaluation est fondée sur six catégories d’indicateurs de coproduction des connaissances : facteurs externes, intrants, processus, extrants, résultats et incidences. Deux sources de données ont été employées pour évaluer les indicateurs : des entrevues avec les membres du comité directeur et des gestionnaires scientifiques externes (n = 16), et l’examen des procès-verbaux du comité directeur. L’interprétation des indicateurs d’extrants et de résultats suggère que le programme d’études de base a appuyé un large éventail de recherches, mais qu’il y avait des différences dans la façon dont les groupes percevaient la pertinence et la légitimité des résultats du projet. Plusieurs variables d’intrants, de processus et de facteurs externes ont permis la coproduction de données scientifiques fiables dans une organisation frontalière émergente et un espace contesté. Ces variables comprenaient les mécanismes de gouvernance, les capacités utilisées et l’inclusion des connaissances traditionnelles. Parmi les défis propres à la coproduction de connaissances à North Slope, notons des défis de logistique, de différences sur les plans de la culture et des contextes décisionnels, ainsi que l’équilibre des compromis entre les perceptions en matière de crédibilité, de légitimité et de pertinence. Quant aux leçons apprises, notons la nécessité d’accorder du temps pour favoriser la confiance, d’élaborer des méthodes de gouvernance adaptatives et de renforcer les capacités chez les scientifiques pour traduire les préoccupations communautaires en questions de recherche
Thresholds for Pebbling on Grids
Given a connected graph and a configuration of pebbles on the
vertices of G, a -pebbling step consists of removing pebbles from a
vertex, and adding a single pebble to one of its neighbors. Given a vector
, -pebbling consists of allowing
-pebbling in coordinate . A distribution of pebbles is called solvable
if it is possible to transfer at least one pebble to any specified vertex of
via a finite sequence of pebbling steps.
In this paper, we determine the weak threshold for -pebbling on the
sequence of grids for fixed and , as . Further,
we determine the strong threshold for -pebbling on the sequence of paths of
increasing length. A fundamental tool in these proofs is a new notion of
centrality, and a sufficient condition for solvability based on the well used
pebbling weight functions; we believe this weight lemma to be the first result
of its kind, and may be of independent interest.
These theorems improve recent results of Czygrinow and Hurlbert, and Godbole,
Jablonski, Salzman, and Wierman. They are the generalizations to the random
setting of much earlier results of Chung.
In addition, we give a short counterexample showing that the threshold
version of a well known conjecture of Graham does not hold. This uses a result
for hypercubes due to Czygrinow and Wagner.Comment: 16 pages; comments are welcom
Tur\`an numbers of Multiple Paths and Equibipartite Trees
The Tur\'an number of a graph H, ex(n;H), is the maximum number of edges in
any graph on n vertices which does not contain H as a subgraph. Let P_l denote
a path on l vertices, and kP_l denote k vertex-disjoint copies of P_l. We
determine ex(n, kP_3) for n appropriately large, answering in the positive a
conjecture of Gorgol. Further, we determine ex (n, kP_l) for arbitrary l, and n
appropriately large relative to k and l. We provide some background on the
famous Erd\H{o}s-S\'os conjecture, and conditional on its truth we determine
ex(n;H) when H is an equibipartite forest, for appropriately large n.Comment: 17 pages, 13 figures; Updated to incorporate referee's suggestions;
minor structural change
Groundwater Depletion and Agricultural Land Use Change in Wichita County, Kansas
Though researchers have documented groundwater and land use changes in the High Plains, few studies have investigated their interactions. This paper examines the relationship between groundwater depletion and agricultural land use change in greater detail than previous studies. Water well measurements and satellite imagery were used to detect changes in groundwater and land cover in Wichita County, Kansas, between 1975 and 2001. Analysis of these changes using GIS indicated that areas experiencing the greatest decline in groundwater were indeed being removed from irrigation, while areas with limited groundwater decline were experiencing fewer land use changes
Conceptualizing the Science-Practice Interface: Lessons from a Collaborative Network on the Front-Line of Climate Change
The gap between science and practice is widely recognized as a major concern in the production and application of decision-relevant science. This research analyzed the roles and network connections of scientists, service providers, and decision makers engaged in climate science and adaptation practice in Alaska, where rapid climate change is already apparent. Our findings identify key actors as well as significant differences in the level of bonding ties between network members who perceive similarity in their social identities, bridging ties between network members across different social groups, and control of information across roles—all of which inform recommendations for adaptive capacity and the co-production of usable knowledge. We also find that some individuals engage in multiple roles in the network suggesting that conceptualizing science policy interactions with the traditional categories of science producers and consumers oversimplifies how experts engage with climate science, services, and decision making. Our research reinforces the notion that the development and application of knowledge is a networked phenomenon and highlights the importance of centralized individuals capable of playing multiple roles in their networks for effective translation of knowledge into action
Integrating scientific and local knowledge to inform risk-based management approaches for climate adaptation
AbstractRisk-based management approaches to climate adaptation depend on the assessment of potential threats, and their causes, vulnerabilities, and impacts. The refinement of these approaches relies heavily on detailed local knowledge of places and priorities, such as infrastructure, governance structures, and socio-economic conditions, as well as scientific understanding of climate projections and trends. Developing processes that integrate local and scientific knowledge will enhance the value of risk-based management approaches, facilitate group learning and planning processes, and support the capacity of communities to prepare for change. This study uses the Vulnerability, Consequences, and Adaptation Planning Scenarios (VCAPS) process, a form of analytic-deliberative dialogue, and the conceptual frameworks of hazard management and climate vulnerability, to integrate scientific and local knowledge. We worked with local government staff in an urbanized barrier island community (Sullivan’s Island, South Carolina) to consider climate risks, impacts, and adaptation challenges associated with sea level rise and wastewater and stormwater management. The findings discuss how the process increases understanding of town officials’ views of risks and climate change impacts to barrier islands, the management actions being considered to address of the multiple impacts of concern, and the local tradeoffs and challenges in adaptation planning. We also comment on group learning and specific adaptation tasks, strategies, and needs identified
Neutrophil elastase and myeloperoxidase regulate the formation of neutrophil extracellular traps
Neutrophil elastase escapes azurophilic granules, translocates to the nucleus, and degrades histones to promote chromatin decondensation necessary for NET formation
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