The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Beatriz Díez - One of the best experts on this subject based on the ideXlab platform.
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Multifaceted approach for the analysis of the phototrophic microbial community in a freshwater Recreational Area of Xochimilco, México.
Hydrobiologia, 2009Co-Authors: Rosaluz Tavera, Beatriz DíezAbstract:The freshwater microbial community in a Recreational Area of Xochimilco, Mexico was investigated and compared based on spatial (three different sites) and temporal (dry and rainy seasons) environmental variables. Many of the 16S- and 18S rRNA gene sequences recovered by DGGE fingerprinting analysis were related to phototrophic microbial phylotypes of known identity. Our genetic and morphological analysis indicated the ubiquitous presence of the microeukaryotic green algae Desmodesmus-Scenedesmus spp. and of the unicellular cyanobacteria Cyanobium spp. as the most representative populations in the samples. While 18S rRNA-DGGE fingerprinting analysis revealed a homogeneous community composition across sites and seasons, the 16S rRNA showed significant differences between localities and seasons. None of the cyanobacteria species with potential to produce toxins were identified across the investigated samples. Correlations between biotic and abiotic variables evidenced an important difference between the dry and the rainy season, with a greater consistency in data from the rainy season. According to Principal Component Analysis (PCA), a strong relation between inorganic nitrogen, species richness, and subaquatic irradiance determines environmental variability in Xochimilco. Complementary and relevant data in results obtained from microscopy, fingerprinting, and statistical analysis applied in ecology indicate that a multifaceted approach to the study of microbial communities is necessary to accomplish a comprehensive scientific framework and to generate proper management strategies.
Martin Pfeffer - One of the best experts on this subject based on the ideXlab platform.
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DISPATCHES Spotted Fever Group Rickettsiae in Ticks, Germany
2013Co-Authors: Cornelia Silaghi, Kurt Pfister, Dietmar Hamel, Claudia Thiel, Martin PfefferAbstract:To explore increased risk for human Rickettsia spp. infection in Germany, we investigated Recreational Areas and renatured brown coal surface-mining sites (also used for recreation) for the presence of spotted fever group rickettsiae in ticks. R. raoultii (56.7%), R. slovaca (13.3%), and R. helvetica (>13.4%) were detected in the respective tick species. Rickettsia species of the spotted fever group are causing emerging infectious diseases (1). Since 1977, Rickettsia slovaca, found in Dermacentor marginatus ticks, was the only known Rickettsia sp. in Germany until 2002, when the following were identified: R. monacensis and R. helvetica in Ixodes ricinus ticks, Rickettsia sp. RpA4 (now R. raoultii) in D. reticulatus ticks, R. felis in Ctenocephalides felis cat fleas, and R. massiliae in I. ricinus ticks (1,2). All of these species cause tick-borne rickettsioses in humans, including tick-borne lymphadenopathy (TIBOLA) (3–7). The aim of this study was to explore the interface between the vector tick and humans by investigating the presence of Rickettsia spp. in ticks at highly frequented Recreational Areas and renatured brown coal surface-mining sites that also are used for leisure. The Study Questing ticks were collected from vegetation by flagging in 3 regions in Germany (9 sites total) in March– September 2008 and April–October 2009 (Figure). Three sites, including renatured gravel pits and walking Areas near villages and cities (A–C), were located in the federal state of Saarland. One site in southern Germany was in a natural alluvial forest north of Munich, popular for hiking and dog walking (D), and in East Germany (Saxony), 3 sites were former brown coal surface-mining Areas near the city of Leipzig (E–G). Ongoing renaturation and flooding of the pit holes during past decades created a highly valuable Recreational Area with artificial lakes and surrounding meadows and forest (www.leipzigerneuseenland.de). Here, sampling was carried out around Lake Cospuden (436 ha
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isolation and molecular characterization of a tick borne encephalitis virus strain from a new tick borne encephalitis focus with severe cases in bavaria germany
Ticks and Tick-borne Diseases, 2010Co-Authors: Anne M Kupca, Sandra Essbauer, Gudrun Zoeller, Philippe Gil De Mendonca, Roland Brey, Monika Rinder, Kurt Pfister, Martin Spiegel, Bastian Doerrbecker, Martin PfefferAbstract:Tick-borne encephalitis (TBE) is the most important viral infection transmitted by ticks in Central Europe. In Germany, where TBE was classified as a notifiable disease in 2001, a highly variable number of clinically apparent human cases was reported in the last few years, ranging from the lowest number of 238 in 2007 to a maximum of 546 in 2006. The dynamics of the virus and its vector tick remain poorly understood. We investigated a highly active TBE focus in south-eastern Germany where from 2003 to 2008 a total of 9 clinical human cases was diagnosed. Three out of these 9 cases were fatal indicating an unusually high mortality rate possibly due to a highly virulent TBEV strain. From 2005 till 2008, 2150 Ixodes ricinus ticks were collected and tested for the presence of TBE virus. Five TBEV-positive ticks were detected by real-time RT-PCR. A viable virus strain was isolated from one of the positive ticks sampled in 2005. This is the first TBE virus isolate from a tick in Germany for 30 years. Sequencing of the full-length genome of this virus strain (AS33) revealed 2 unique amino acid substitutions in the envelope protein known to play a role in the pathogenicity of TBE virus. Amplification of the envelope gene using 2 TBEV-PCR-positive ticks from 2006 also showed these particular mutations indicating that this TBE virus strain was present in at least 2 consecutive years. The entire sampling Area was divided into smaller sectors for the exact location of TBEV-positive ticks. Virus-positive ticks were found to be randomly distributed throughout the investigated focus, which is used as Recreational Area by the local people.
Dirk Goossens - One of the best experts on this subject based on the ideXlab platform.
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arsenic concentrations in dust emissions from wind erosion and off road vehicles in the nellis dunes Recreational Area nevada usa
Aeolian Research, 2012Co-Authors: Deborah Soukup, Brenda J Buck, Dirk Goossens, April L Ulery, Brett T Mclaurin, Dirk Baron, Yuanxin TengAbstract:Field and laboratory experiments were performed in the Nellis Dunes Recreational Area near Las Vegas, NV, USA to evaluate arsenic concentrations associated with dust emissions from wind erosion and offroad vehicles. Soil samples were collected from 17 types of desert surfaces and five unpaved parking lot locations for analyses. The surface units are based on surficial characteristics that affect dust emissions. Arsenic concentrations were also measured in dust emitted from each surface unit using a Portable In Situ Wind Erosion Laboratory (PI-SWERL). Emissions were measured from ORV trails and undisturbed terrain. Concentrations of As in the soil and parking lot samples ranged from 3.49 to 83.02 l gg 1
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contributions to atmospheric dust production of natural and anthropogenic emissions in a Recreational Area designated for off road vehicular activity nellis dunes nevada usa
Journal of Arid Environments, 2012Co-Authors: Brenda J Buck, Dirk Goossens, Brett T MclaurinAbstract:Abstract Wind erosion measurements and experiments with off-road vehicles (ORV) were conducted in the Nellis Dunes Recreation Area (NDRA) near Las Vegas, Nevada. Wind erosion was measured during one complete year. ORV emissions were measured for 3 types of vehicles (dirt bikes, dune buggies, 4-wheelers) and for various driving speeds up to 56 km h −1 . This study investigates the mutual contributions of wind erosion and ORV in the total emission of dust in NDRA. The highest emissions generated by wind erosion occur in the sandy Areas, and especially in the sand dunes. These Areas produce only very little dust during ORV driving. By far the most ORV dust is generated in Areas of silt and rock-covered silt, where protective surface crusts and surficial rock layers are destroyed by the driving and large reservoirs of emittable dust are available in the top layer. On an annual basis the amounts of dust produced in NDRA are almost equal for wind erosion and ORV. Management in the NDRA is complicated by the intense wind erosion in the sand dunes. Even while ORV driving does not create significant emissions in these Areas, drivers can potentially inhale large amounts of dust produced locally by wind erosion.
Rosaluz Tavera - One of the best experts on this subject based on the ideXlab platform.
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Multifaceted approach for the analysis of the phototrophic microbial community in a freshwater Recreational Area of Xochimilco, México.
Hydrobiologia, 2009Co-Authors: Rosaluz Tavera, Beatriz DíezAbstract:The freshwater microbial community in a Recreational Area of Xochimilco, Mexico was investigated and compared based on spatial (three different sites) and temporal (dry and rainy seasons) environmental variables. Many of the 16S- and 18S rRNA gene sequences recovered by DGGE fingerprinting analysis were related to phototrophic microbial phylotypes of known identity. Our genetic and morphological analysis indicated the ubiquitous presence of the microeukaryotic green algae Desmodesmus-Scenedesmus spp. and of the unicellular cyanobacteria Cyanobium spp. as the most representative populations in the samples. While 18S rRNA-DGGE fingerprinting analysis revealed a homogeneous community composition across sites and seasons, the 16S rRNA showed significant differences between localities and seasons. None of the cyanobacteria species with potential to produce toxins were identified across the investigated samples. Correlations between biotic and abiotic variables evidenced an important difference between the dry and the rainy season, with a greater consistency in data from the rainy season. According to Principal Component Analysis (PCA), a strong relation between inorganic nitrogen, species richness, and subaquatic irradiance determines environmental variability in Xochimilco. Complementary and relevant data in results obtained from microscopy, fingerprinting, and statistical analysis applied in ecology indicate that a multifaceted approach to the study of microbial communities is necessary to accomplish a comprehensive scientific framework and to generate proper management strategies.
BP Clifford - One of the best experts on this subject based on the ideXlab platform.
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Only a Town Planner Would Run a Toxic Waste Pipeline Through a Recreational Area’: Planning and Planners in the British Press
Town Planning Review, 2006Co-Authors: BP CliffordAbstract:Given the many planning reforms underway, including the increasing emphasis on public participation, and the many high-profile issues to which planning can be linked, it is an important time to reflect on the media image of planning and planners. This paper draws on the results of a survey of newspaper coverage in British national and local papers in 2003–04 to illustrate how planning and planners are being represented and framed in the media. The results of the survey suggest a frequently stereotypical and critical image in the national print media, with more of a focus on planning in action in the local press. A similar survey of the professional journal Planning suggests a mismatch in public and professional images of planning. Taken together, these results give cause for concern as to how planning is represented in the public press and it is argued that such 'planning pessimism' highlights the need for greater attention to media representations of planning and planners.