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111.
Christiane Santos Matos José Eloy dos Santos Júnior Fernanda Alvarenga Cardoso Medeiros Eliana Furtado Jo?o Carlos Pinto Dias 《Memórias do Instituto Oswaldo Cruz》2014,109(3):374-378
Recognising the importance of Chagas disease in Brazil, Bambuí set up epidemiological
surveillance for Chagas disease in 1974 and was the first municipality to do so. To
ascertain the current epidemiology of Chagas disease in this municipality, 1.782
blood samples from the general population were analysed; 7.7% of samples were found
to be seropositive for Chagas disease. A strong positive correlation between
increasing age and Chagas disease was evident in both genders, with the highest
prevalence in individuals aged over 60 years. Clinically, the cardiodigestive form of
Chagas disease was the most common in these samples. These data confirm the
interruption of Trypanosoma cruzi transmission, in parallel with a
still important residual morbidity of Chagas disease in the county, thus supporting
political decisions that will prioritise epidemiological surveillance and medical
treatment of Chagas disease in the coming years. 相似文献
112.
Daniel B. Metcalfe Gregory P. Asner Roberta E. Martin Javier E. Silva Espejo Walter Huaraca Huasco Felix F. Farfán Amézquita Loreli Carranza‐Jimenez Darcy F. Galiano Cabrera Liliana Durand Baca Felipe Sinca Lidia P. Huaraca Quispe Ivonne Alzamora Taype Luzmila Eguiluz Mora Angela Rozas Dávila Marlene Mamani Solórzano Beisit L. Puma Vilca Judith M. Laupa Román Patricia C. Guerra Bustios Norma Salinas Revilla Raul Tupayachi Cécile A. J. Girardin Christopher E. Doughty Yadvinder Malhi 《Ecology letters》2014,17(3):324-332
The functional role of herbivores in tropical rainforests remains poorly understood. We quantified the magnitude of, and underlying controls on, carbon, nitrogen and phosphorus cycled by invertebrate herbivory along a 2800 m elevational gradient in the tropical Andes spanning 12°C mean annual temperature. We find, firstly, that leaf area loss is greater at warmer sites with lower foliar phosphorus, and secondly, that the estimated herbivore‐mediated flux of foliar nitrogen and phosphorus from plants to soil via leaf area loss is similar to, or greater than, other major sources of these nutrients in tropical forests. Finally, we estimate that herbivores consume a significant portion of plant carbon, potentially causing major shifts in the pattern of plant and soil carbon cycling. We conclude that future shifts in herbivore abundance and activity as a result of environmental change could have major impacts on soil fertility and ecosystem carbon sequestration in tropical forests. 相似文献
113.
114.
C Grilo J Sousa F Ascensão H Matos I Leitão P Pinheiro M Costa J Bernardo D Reto R Lourenço M Santos-Reis E Revilla 《PloS one》2012,7(9):e43811
Background
Understanding the ecological consequences of roads and developing ways to mitigate their negative effects has become an important goal for many conservation biologists. Most mitigation measures are based on road mortality and barrier effects data. However, studying fine-scale individual spatial responses in roaded landscapes may help develop more cohesive road planning strategies for wildlife conservation.Methodology/Principal Findings
We investigated how individuals respond in their spatial behavior toward a highway and its traffic intensity by radio-tracking two common species particularly vulnerable to road mortality (barn owl Tyto alba and stone marten Martes foina). We addressed the following questions: 1) how highways affected home-range location and size in the immediate vicinity of these structures, 2) which road-related features influenced habitat selection, 3) what was the role of different road-related features on movement properties, and 4) which characteristics were associated with crossing events and road-kills. The main findings were: 1) if there was available habitat, barn owls and stone martens may not avoid highways and may even include highways within their home-ranges; 2) both species avoided using areas near the highway when traffic was high, but tended to move toward the highway when streams were in close proximity and where verges offered suitable habitat; and 3) barn owls tended to cross above-grade highway sections while stone martens tended to avoid crossing at leveled highway sections.Conclusions
Mortality may be the main road-mediated mechanism that affects barn owl and stone marten populations. Fine-scale movements strongly indicated that a decrease in road mortality risk can be realized by reducing sources of attraction, and by increasing road permeability through measures that promote safe crossings. 相似文献115.
116.
Jonàs Juan-Mateu Maria José Rodríguez Andrés Nascimento Cecilia Jiménez-Mallebrera Lidia González-Quereda Eloy Rivas Carmen Paradas Marcos Madruga Pedro Sánchez-Ayaso Cristina Jou Laura González-Mera Francina Munell Manuel Roig-Quilis Maria Rabasa Aurelio Hernández-Lain Jorge Díaz-Manera Eduard Gallardo Jordi Pascual Edgard Verdura Jaume Colomer Montserrat Baiget Montse Olivé Pia Gallano 《Orphanet journal of rare diseases》2012,7(1):1-13
Background
Neonatal screening for Pompe disease has been introduced in Taiwan and a few U.S. states, while other jurisdictions including some European countries are piloting or considering this screening. First-tier screening flags both classic infantile and late-onset Pompe disease, which challenges current screening criteria. Previously, advocacy groups have sometimes supported expanded neonatal screening more than professional experts, while neutral citizens' views were unknown. This study aimed to measure support for neonatal screening for Pompe disease in the general public and to compare it to support among (parents of) patients with this condition. The study was done in the Netherlands, where newborns are not currently screened for Pompe disease. Newborn screening is not mandatory in the Netherlands but current uptake is almost universal.Methods
A consumer panel (neutral group) and (parents of) patients with Pompe disease (Pompe group) were sent information and a questionnaire. Responses were analyzed of 555 neutral and 58 Pompe-experienced informants who had demonstrated sufficient understanding.Results
87% of the neutral group and 88% of the Pompe group supported the introduction of screening (95% CI of difference -10 to 7%). The groups were similar in their moral reasoning about screening and acceptance of false positives, but the Pompe-experienced group expected greater benefit from neonatal detection of late-onset disease. Multivariate regression analysis controlling for demographics confirmed that approval of the introduction of screening was independent of having (a child with) Pompe disease. Furthermore, respondents with university education, regardless of whether they have (a child with) Pompe disease, were more likely to be reluctant about the introduction of screening than those with less education, OR for approval 0.29 (95% CI 0.18 to 0.49, p < 0.001).Conclusions
This survey suggests a rather high level of support for newborn screening for Pompe disease, not only among those who have personal experience of the disease but also among the general public in the Netherlands. Optional screening on the basis of informed parental consent is probably unrealistic, underlining the need for new guidelines to help policymakers in their consideration of newborn screening for broad phenotype conditions. 相似文献117.
The growth and gender in the gametophyte of Blechnum spicant L. were strongly affected by its origin, spore or mature homogenized gametophytes, and also by the addition of plant growth regulators to the culture medium. Spore-derived gametophytes cultured in Murashige and Skoog liquid medium were females and heart-shaped, whereas those derived from mature homogenized gametophytes were shorter and male or asexual (1:3) because of the release of antheridiogen to the culture medium. In the latter, maleness was especially increased by the addition of BA. This cytokinin is a strong inductor of maleness in homogenized cultures; however, even though BA influenced sexual organ formation in spore-derived gametophytes, it does not change the␣female sexual pattern that these gametophytes have. Separate male and female populations of gametophytes were obtained in this work. 相似文献
118.
The occurrence of intestinal parasites in swine slurry and their removal in activated sludge plants 总被引:1,自引:0,他引:1
Thirteen intensive pig farms and two activated sludge treatment plants for pig slurry in north-western Spain were studied from April 2005 to June 2006 in order to evaluate the presence of enteric pathogens (Cryptosporidium, Giardia and helminths) and the efficiency with which they were removed. These parasites were present on 53%, 7% and 38% of the farms studied, respectively, with concentrations of 10(4)-10(5) oocysts per litre (/L) for Cryptosporidium, 10(3)cysts/L for Giardia and 10(2)-10(3) eggs/L for helminths. The overall removal of parasites in the pig slurry treatment plants ranged from 86.7% to over 99.99%. The results revealed a constant reduction at each stage of the treatment system, with activated sludge processes being the most effective treatment in reducing pathogens in pig slurry, 78-81% for Cryptosporidium oocysts and over 99.9% for helminth eggs. A heat drying procedure for sludge removed 4.3 log units of Cryptosporidium oocysts, demonstrating the excellent effectiveness of this treatment for reducing pathogens in sludge intended to be applied to land. 相似文献
119.
Endogenous levels of two gibberellins, GA3 andGA20, were quantified in unimbibed Onopordumnervosum seeds collected from two different populations, whichshoweddifferences in their germination capacity. After purifying the seed extracts,gibberellin levels were evaluated by gas chromatography mass spectrometry byusing selected ion monitoring (GC-MS-SIM) adding deuterated gibberellins asinternal standards. The intraspecific differences in germination capacity wereassociated with differences in the endogenous levels of both gibberellins. Thecontents of GA3 and GA20 in seeds with high germinationrate were twice and five times higher, respectively, than those from seeds witha low germination rate, indicating a possible role of gibberellins in dormancyrelease in this plant species. 相似文献
120.
A 2-year experimental study on nutrient and predator influences on food web constituents in a shallow lake of north-west Spain 总被引:3,自引:0,他引:3
Margarita Fernández-Aláez Camino Fernández-Aláez Eloy Bécares María Valentín Joan Goma Pedro Castrillo 《Freshwater Biology》2004,49(12):1574-1592
1. A 2‐year study was carried out on the roles of nutrients and fish in determining the plankton communities of a shallow lake in north‐west Spain. Outcomes were different each year depending on the initial conditions, especially of macrophyte biomass. In 1998 estimated initial ‘per cent water volume inhabited’ (PVI) by submerged macrophytes was about 35%. Phytoplankton biomass estimated as chlorophyll a was strongly controlled by fish, whereas effects of nutrient enrichment were not significant. In 1999 estimated PVI was 80%, no fish effect was observed on phytoplankton biomass, but nutrients had significant effects. Water temperatures were higher in 1998 than in 1999. 2. In the 1998 experiment, cladoceran populations were controlled by fish and cyanobacteria were the dominant phytoplankton group. There were no differences between effects of low (4 g fresh mass m?2) and high (20 g fresh mass m?2) fish density on total zooplankton biomass, but zooplankton biomass was higher in the absence of fish. With the high plant density in 1999, fish failed to control any group of the zooplankton community. 3. Total biovolume of phytoplankton strongly decreased with increased nutrient concentrations in 1998, although chlorophyll a concentrations did not significantly change. At higher nutrient concentrations, flagellate algae became more abundant with likely growth rates that could have overcompensated cladoceran feeding rates. This change in phytoplankton community composition may have been because of increases in the DIN : SRP ratio. Both chlorophyll a concentration and total phytoplankton biovolume increased significantly with nutrients in the 1999 experiment. 4. A strong decline of submerged macrophytes was observed in both years as nutrients increased, resulting in shading by periphyton. This shading effect could account for the plant decline despite lower water turbidity at the very high nutrient levels in 1998. 相似文献