532 research outputs found

    Invasion of winter moth in New England: Effects of defoliation and site quality on tree mortality.

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    Abstract Widespread and prolonged defoliation by the European winter moth, Operophtera brumata L., has occurred in forests of eastern Massachusetts for more than a decade and populations of winter moth continue to invade new areas of New England. This study characterized the forests of eastern Massachusetts invaded by winter moth and related the duration of winter moth defoliation estimated using dendrochronology to observed levels of tree mortality and understory woody plant density. Quercus basal area mortality in mixed Quercus and mixed Quercus-Pinus strobus forests in eastern Massachusetts ranged from 0-30%; mortality of Quercus in these forests was related to site quality and the number of winter moth defoliation events. In addition, winter moth defoliation events lead to a subsequent increase in understory woody plant density. Our results indicate that winter moth defoliation has been an important disturbance in New England forests that may have lasting impacts

    Pengembangan UMKM sebagai Penguatan Ekonomi Kerakyatan di Kota Bukittinggi (Studi Kasus: Industri Kerupuk Sanjai)

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    This study aims the problems faced by home industry kerupuk Sanjai in the City of Bukittinggi to improve local economy. This study was conducted in March 2015 through a survey method (observation) with random purposive sampling technique. The sample in this study as many as twenty-six home industry Kerupuk Sanjai in Bukittinggi. This research found home industry Kerupuk Sanjai in Bukittinggi city is still traditional both in the production process, packaging and marketing system. So that the necessary cooperation with the relevant agencies in order to create innovation and creativity to improve quality and productivity as well as a broader marketing reach

    Cascade Dynamics of Multiplex Propagation

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    Random links between otherwise distant nodes can greatly facilitate the propagation of disease or information, provided contagion can be transmitted by a single active node. However we show that when the propagation requires simultaneous exposure to multiple sources of activation, called multiplex propagation, the effect of random links is just the opposite: it makes the propagation more difficult to achieve. We calculate analytical and numerically critical points for a threshold model in several classes of complex networks, including an empirical social network.Comment: 4 pages, 5 figures, for similar work visit http://hsd.soc.cornell.edu and http://www.imedea.uib.es/physdep

    Acting to Address the Ocean-Related Impacts of Climate Change on Human and National Security, with Recommendations for Priority Actions drawn from the discussions of the Global Conference on Oceans, Climate and Security at the University of Massachusetts Boston

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    In the course of the past calendar year the United States has been struck by a series of droughts, tornadoes, hurricanes, blizzards, wildfires, and floods whose size and path of resulting damage defy previously established patterns. The U.S. thus joins nations on every continent that have increasingly experienced extreme and extremely damaging weather events over the past two decades. At the same time, the world’s oceans have been exhibiting a less-visible but equally dangerous sequence of temperature rise, acidification increase, fish kills, coastal erosion, salinity shifts, algae blooms, and steady decreases in commercially available fish and shellfish species. Those impacts are not only significant indicators of a climate change that is rapidly increasing in the natural world, they are also warning signals of the effects of that changing climate on national and human security. A new focus is emerging on how climate change impacts ocean systems, the oceans’ subsequent vital role in exacerbating or mitigating those impacts, and how both climate and ocean systems substantially impact national security. The stunning effects of Hurricane Sandy provided only an initial glimpse of the extensive primary, secondary, and tertiary impacts that will result from these system shifts domestically and internationally. Understanding the interconnectedness among oceans, climate, and security is therefore increasingly crucial to our collective future. The first Global Conference on Oceans, Climate and Security (GC ’12) was designed to raise awareness of the effects of climate change on ocean systems and the consequent impacts on national and international security. The conference attempted to identify and prioritize the knowledge gaps in science and technology that have inhibited understanding, response, and adaptation to future threats and opportunities. It then generated a series of human security policy and governance recommendations reflecting the climate, ocean, and security continuum. Participants agreed that the required solutions were not the responsibility of either the public sector (government), the private sector (business), or the voluntary sector (NGOs) alone—but were the responsibilities of all of these working together. They also emphasized the potential in approaching the issues from the perspective of positive economic and social opportunity, rather than focusing solely on risks and threats. This white paper presents the observations of the conference and highlights its primary conclusions. It then expands upon those to include the extraordinary impacts—both physical and political—of the recent and ongoing series of extreme-weather phenomena that peaked in 2012 with the devastation of Sandy and has continued in 2013 with a melting Arctic and floods across the U.S. Midwest

    Effects of Invasive Winter Moth Defoliation on Tree Radial Growth in Eastern Massachusetts, USA

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    Winter moth, Operophtera brumata L. (Lepidoptera: Geometridae), has been defoliating hardwood trees in eastern Massachusetts since the 1990s. Native to Europe, winter moth has also been detected in Rhode Island, Connecticut, eastern Long Island (NY), New Hampshire, and Maine. Individual tree impacts of winter moth defoliation in New England are currently unknown. Using dendroecological techniques, this study related annual radial growth of individual host (Quercus spp. and Acer spp.) trees to detailed defoliation estimates. Winter moth defoliation was associated with up to a 47% reduction in annual radial growth of Quercus trees. Latewood production of Quercus was reduced by up to 67% in the same year as defoliation, while earlywood production was reduced by up to 24% in the year following defoliation. Winter moth defoliation was not a strong predictor of radial growth in Acer species. This study is the first to document impacts of novel invasions of winter moth into New England

    The shocklet transform: a decomposition method for the identification of local, mechanism-driven dynamics in sociotechnical time series

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    We introduce a qualitative, shape-based, timescale-independent time-domain transform used to extract local dynamics from sociotechnical time series—termed the Discrete Shocklet Transform (DST)—and an associated similarity search routine, the Shocklet Transform And Ranking (STAR) algorithm, that indicates time windows during which panels of time series display qualitatively-similar anomalous behavior. After distinguishing our algorithms from other methods used in anomaly detection and time series similarity search, such as the matrix profile, seasonal-hybrid ESD, and discrete wavelet transform-based procedures, we demonstrate the DST’s ability to identify mechanism-driven dynamics at a wide range of timescales and its relative insensitivity to functional parameterization. As an application, we analyze a sociotechnical data source (usage frequencies for a subset of words on Twitter) and highlight our algorithms’ utility by using them to extract both a typology of mechanistic local dynamics and a data-driven narrative of socially-important events as perceived by English-language Twitter

    Infrapatellar Straps Decrease Patellar Tendon Strain at the Site of the Jumper’s Knee Lesion

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    Background: The impetus for the use of patellar straps in the treatment of patellar tendinopathy has largely been based on empirical evidence and not on any mechanistic rationale. A computational model suggests that patellar tendinopathy may be a result of high localized tendon strains that occur at smaller patella–patellar tendon angles (PPTAs). Hypothesis: Infrapatellar straps will decrease the mean localized computational strain in the area of the patellar tendon commonly involved in jumper’s knee by increasing the PPTA. Study Design: Controlled laboratory study. Methods: Twenty adult males had lateral weightbearing and nonweightbearing radiographs of their knees taken with and without 1 of 2 infrapatellar straps at 60° of knee flexion. Morphologic measurements of PPTA and patellar tendon length with and without the straps were used as input data into a previously described computational model to calculate average and maximum strain at the common location of the jumper’s knee lesion during a simulated jump landing. Results: The infrapatellar bands decreased the predicted localized strain (average and maximum) in the majority of participants by increasing PPTA and/or decreasing patellar tendon length. When both PPTA and patellar tendon length were altered by the straps, there was a strong and significant correlation with the change in predicted average localized strain with both straps. Conclusion: Infrapatellar straps may limit excessive patella tendon strain at the site of the jumper’s knee lesion by increasing PPTA and decreasing patellar tendon length rather than by correcting some inherent anatomic or functional abnormality in the extensor apparatus. Clinical Relevance: The use of infrapatellar straps may help prevent excessive localized tendon strains at the site of the jumper’s knee lesion during a jump landing
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