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41.
With an apparent increase of harmful algal blooms (HABs) worldwide, healthcare providers, public health personnel and coastal managers are struggling to provide scientifically-based appropriately-targeted HAB outreach and education. Since 1998, the Florida Poison Information Center-Miami, with its 24 hour/365 day/year free Aquatic Toxins Hotline (1–888–232–8635) available in several languages, has received over 25,000 HAB-related calls. As part of HAB surveillance, all possible cases of HAB-related illness among callers are reported to the Florida Health Department. This pilot study evaluated an automated call processing menu system that allows callers to access bilingual HAB information, and to speak directly with a trained Poison Information Specialist. The majority (68%) of callers reported satisfaction with the information, and many provided specific suggestions for improvement. This pilot study, the first known evaluation of use and satisfaction with HAB educational outreach materials, demonstrated that the automated system provided useful HAB-related information for the majority of callers, and decreased the routine informational call workload for the Poison Information Specialists, allowing them to focus on callers needing immediate assistance and their healthcare providers. These results will lead to improvement of this valuable HAB outreach, education and surveillance tool. Formal evaluation is recommended for future HAB outreach and educational materials.  相似文献   
42.

Sites in need of restoration typically have one or more environmental factors that limit seedling establishment. Identifying ecophysiological responses to environmental stressors can provide important insights into mitigating measures that would allow seedlings to overcome such constraints to survival. Koa (Acacia koa A. Gray) is a nitrogen-fixing tree species endemic to Hawai?i that is highly valued in restoring degraded forest ecosystems, which are often limited in available water and phosphorus. This study examined how koa seedlings respond to conditions of reduced water (65 W) and no phosphorus (0P). After 17 weeks, seedlings subjected to 65 W or 0P accumulated less biomass, smaller root-collar diameters, and lower nitrogen and phosphorus contents. Combined reductions in water and P resulted in seedlings with increased root to shoot dry biomass and shorter shoots. Seedlings subjected to 65 W also had lower instantaneous rates of CO2 assimilation, but higher instantaneous water-use efficiencies following irrigation, suggesting that koa responds to water deficits by decreasing water loss via reduced stomatal conductance. Seedlings subjected to 0P had similar rates of CO2 assimilation relative to those grown with adequate P, suggesting that koa is able to employ strategies to avoid physiological impairment from conditions of inadequate P. Future research should assess whether subjecting koa seedlings to reduced water before planting on water-limited sites cues increased drought resistance and whether uptake and storage of P by seedlings in the nursery better supports growth following outplanting, particularly on sites with anticipated low plant-available water.

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43.
44.
In recent years, Texas has seen a dramatic increase in the number of clinical cases of Corynebacterium pseudotuberculosis (pigeon fever) infection in horses. Equine pigeon fever cases at Texas Veterinary Medical Diagnostic Laboratories (TVMDL) were analyzed with the objectives of investigating the spatiotemporal distribution and seasonal and annual trends of pigeon fever infection in horses in Texas between 2005 and 2011 and identifying high-risk areas and create a risk map for pigeon fever in horses in Texas. The study population consisted of horses culture-positive for C. pseudotuberculosis between January 1, 2005, and December 31, 2011 at TVMDL. The Poisson model of scan statistics was fitted to identify disease clusters. Empirical Bayesian smoothing was performed with the crude incidence estimates, followed by the geostatistical method of kriging to delineate high-risk areas. Cases increased 10-fold between 2005 and 2011. The annual cumulative incidence ranged from 9.3 to 99.5 per 100,000 horses at risk. Two seasonal peaks in the number of cases were observed in June and in December. Scan statistics identified a primary cluster in central Texas in 2011 (P < .0001 and relative risk of 9.2). Isopleth risk mapping also delineated a high-risk area in central Texas. High-risk areas were also detected in the panhandle and northern Texas. The epidemiological investigation supported anecdotal reports that pigeon fever is re-emerging in the Texas horse population. This study provides a baseline for future investigations of pigeon fever in the Texas horse population and serves as a reference for the disease distribution for veterinarians and horse owners.  相似文献   
45.
A new data aggregation technique to improve landscape metric downscaling   总被引:1,自引:1,他引:0  
Scale is a fundamental concept in landscape ecology and considerable attention has been given to the scale-dependent relationships of landscape metrics. Many metrics have been found to exhibit very consistent scaling relationships as map resolution (i.e., pixel or grain size) is increased. However, these scaling relationships tend to break down when attempting to ‘downscale’ them, and the scaling function is often unable to accurately predict metric values for finer resolutions than the original data. The reasons for this breakdown are not well understood. This research examines the downscaling behavior of metrics using various data aggregation techniques in an attempt to better understand the characteristics of metric scaling behavior. First, downscaling performance is examined using the traditional method of aggregation known as ‘majority rules’. Second, a new data aggregation technique is introduced that utilizes fractional land cover abundances obtained from sub-pixel remote sensing classifications in order to capture a greater amount of the spatial heterogeneity present in the landscape. The goal of this new aggregation technique is to produce a more accurate scaling relationship that can be downscaled to predict metric values at fine resolutions. Results indicate that sub-pixel classifications have the potential to transform data aggregation to allow more accurate downscaling for certain landscapes, but accuracy is linked to the spatial heterogeneity of the landscape.  相似文献   
46.
Green roofs provide a number of valuable ecosystem services compared to conventional roofs, but may require yearly maintenance. Trees and other woody plants that persist on the roof may damage or overload shallow-substrate green roofs and their removal is a standard maintenance procedure. The germination potential of colonizing species may differ depending on the vegetation surrounding them. The aim of this study was to determine whether the germination of colonizing tree species (Picea glauca and Ulmus glabra) will vary depending on which plant species form the established vegetation seeds land in. To determine germination success, survival, and seed capture ability of the plant canopy, tree seeds were added either directly to the growing medium or atop the plant canopy, in replicated monocultures of 14 species native to Nova Scotia. When seeds were added directly to the soil, no significant difference was detected between the monocultures for germination success or survival for U. glabra or P. glauca. However, when the seeds were added atop the plant canopy, percent germination of U. glabra was significantly higher in Carex argyrantha green roof modules. Overall, sod forming graminoids showed higher germination of U. glabra. The number of seeds reaching the soil was typically lower in vegetation with a denser canopy. This study demonstrates that some vegetation repels colonizing tree species by reducing ground contact. Although these effects differed according to tree species, non-vegetated substrates enhanced seedling persistence. Additionally, the majority of tree seeds that germinated failed to survive a single growing-season on shallow-substrate green roofs.  相似文献   
47.
Biosurfactants are biomolecules produced by microorganisms, low in toxicity, biodegradable, and relatively easy to synthesize using renewable waste substrates. Biosurfactants are of great importance with a wide and versatile range of applications, including the bioremediation of contaminated sites. Plants may accumulate soil potentially toxic elements(PTEs), and the accumulation efficacy may be further enhanced by the biosurfactants produced by rhizospheric microorganisms. Occasionally, the growth of bacteria slows down in adverse conditions, such as highly contaminated soils with PTEs. In this context,the plant's phytoextraction capacity could be improved by the addition of metal-tolerant bacteria that produce biosurfactants. Several sources, categories,and bioavailability of PTEs in soil are reported in this article, with the focus on the cost-effective and sustainable soil remediation technologies, where biosurfactants are used as a remediation method. How rhizobacterial biosurfactants can improve PTE recovery capabilities of plants is discussed, and the molecular mechanisms in bacterial genomes that support the production of important biosurfactants are listed. The status and cost of commercial biosurfactant production in the international market are also presented.  相似文献   
48.
Plant Foods for Human Nutrition - Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and affects about 25% of the population globally. Obesity and diabetes are the...  相似文献   
49.
Carbon (C) sequestration potential was quantified for five tree species, commonly used in tree-based intercropping (TBI) and for conventional agricultural systems in southern Ontario, Canada. In the 25-year-old TBI system, hybrid poplar (Populus deltoides × Populus nigra clone DN-177), Norway spruce (Picae abies), red oak (Quercus rubra), black walnut (Juglans nigra), and white cedar (Thuja occidentalis) were intercropped with soybean (Glycine max). In the conventional agricultural system, soybean was grown as a sole crop. Above- and belowground tree C Content, soil organic C, soil respiration, litterfall and litter decomposition were quantified for each tree species in each system. Total C pools for hybrid poplar, white cedar, red oak, black walnut, Norway spruce and a soybean sole-cropping system were 113.4, 99.4, 99.2, 91.5, 91.3, and 71.1 t C ha?1, respectively at a tree density of 111 trees ha?1, including mean tree C content and soil organic C stocks. Net C flux for hybrid poplar, white cedar, red oak, black walnut, Norway spruce and soybean sole-crop were 2.1, 1.4, 0.8, 1.8, 1.6 and ?1.2 t C ha?1 year?1, respectively. Results presented suggest greater atmospheric CO2 sequestration potential for all five tree species when compared to a conventional agricultural system.  相似文献   
50.
Live hatchery feeds were assayed for fatty acids (FA), amino acids (AA), and their ability to support growth and survival of larval and postlarval mahimahi Coryphaena hippurus at two different hatchery stages. Euterpina acuritrons copepods (C), mahimahi yolk-sac larvae (YSL), Artemia parthenogenica brine shrimp nauplii (BSn), A. parthenogenica juveniles (BSj), and Brachionus plicatilis rotifers (R) were assayed, using several enrichment media. There was little difference in AAs among feeds.
Levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were about 10 times higher in YSL than in their feeds. This explains previous findings where first stage larval survival (0–9 days) was not affected by feed HUFA levels. Second stage survival was significantly higher when larvae were fed copepods. Enrichment with 100 ppm SuperSelco greatly improved the survival of larvae that were fed brine shrimp. The even higher omega-3 fatty acids found in copepods appear to be important for survival of larvae under more stressful conditions.
Brine shrimp juveniles enriched with SuperSelco are a good food for postlarval mahimahi. Yolksac larvae of mahimahi are an even better food, promoting faster growth at less cost, for large scale mahimahi aquaculturists. Different batches of yolksac mahimahi larvae varied by a factor of 10 in their concentration of DHA, but always had the highest level of DHA as much as 40% of total fatty acids (FAs). These "high HUFA" batches of YSL also had the highest levels of EPA and total fatty acids. The data suggest that climate and broodstock age may have considerable influence on larval nutrition.  相似文献   
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