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1.
The main water bodies in the Bogotá Savannah have been seriously polluted due to the mismanagement of domestic, agricultural, and industrial wastewater. While there are a number of wastewater treatment facilities in the region, most do not function properly. There is a great need for inexpensive and sustainable wastewater treatment systems that are not technologically sophisticated and that do not require intensive management. The main goal of this study was to quantify the performance and sustainability of treatment wetlands and existing wastewater treatment systems in this region. Using data from the literature, a treatment wetland model was developed, which focused on pollutant removal. The modeled performance was compared to a system of waste stabilization ponds and a sequencing batch reactor. The three systems were subject to cost analysis and an emergy evaluation, leading to the assessment of indicators of cost-benefit for comparison. The economic analysis suggested that the net annual cost of the treatment wetland was US$ 14,672, compared to US$ 14,201 for the stabilization ponds and US$ 54,887 for the batch reactor. The emergy evaluations show that the ponds have the lowest annual emergy flow (6.65 + 16 sej/yr), followed by the constructed wetland (2.88E+17 sej/yr) and the batch reactor (8.86E+17 sej/yr). These results were combined to estimate treatment ratios (contaminants removed per lifetime cost, and contaminants removed per total emergy), cost ratios (cost per volume of water, annual cost per capita, and construction cost per capita), and emergy ratios (treatment yield, renewable emergy, lifetime emprice, construction emprice, non-renewable emergy, empower density, environmental loading, total emergy per volume of water, and emergy per capita).  相似文献   

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Resistance of Helicobacter pylori to clarithromycin is the most common cause of treatment failure in patients with H. pylori infections. This study describes the MICs and the presence of 23S rRNA mutations of H. pylori isolates from Bogotá, D.C., Colombia. H. pylori were isolated from gastric biopsies from patients with functional dyspepsia. Clarithromycin susceptibility was investigated by agar dilution and strains were considered resistant if the MIC was ≥1 μg/ml. DNA sequences of the 23S rRNA gene of strains resistant and sensitive to clarithromycin were determined to identify specific point mutations. Clarithromycin resistance was present in 13.6% of patients by agar dilution. The A2143G, A2142G and A2142C mutations were found in 90.5, 7.1, and 2.4% of H. pylori strains with resistance genotype.The resistant phenotype was associated with 23S rRNA resistance genotype in 85.7% of isolates. The point mutations in 23S rRNA were well correlated with MICs values for clarithromycin.  相似文献   

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Understanding the current epidemiologic dynamic of tuberculosis (TB) in any society requires a holistic approach. In the current paper, the history and behavior of the TB is summarized for Bogotá, Colombia. In prehispanic periods the occurrence of TB was low. During the Conquest and the Colony periods, a moderate increase of pulmonary and abdominal TB was observed. In the 1870s, a great increase in cases of pulmonary TB was associated with the accelerated urbanization process. Since the 1920s, the occurrence of pulmonary TB shifted to the status of an endemic disease. After 1920, its occurrence was relatively steady until the 1970s, when its occurence greatly decreased. More recently, however, an increase in case numbers has been observed. The occurrence of TB in each period is associated with clearly defined social and environmental phenomena.  相似文献   

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The presence of Lutzomyia (Helcocyrtomyia) hartmanni, as a vector of Leishmania colombiensis and L. columbiana (Verrucarum group), recently incriminated in the transmission of leishmaniasis, and L. pia (Verrucarum group) are reported for the first time in a periurban area of Medellín city. There is thus a risk of leishmaniasis transmission in this town.  相似文献   

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Land use and land cover change has a marked affect on wetland condition, and different wetland types are affected differentially depending on many abiotic and biotic variables. To assess wetland condition, we have developed a Florida wetland condition index (FWCI) composed of indicators of community structure in the diatom, macrophyte, and macroinvertebrate assemblages for 216 wetlands (n = 74 depressional marsh, n = 118 depressional forested, n = 24 flowing water forested wetlands). Depressional wetlands located along a human disturbance gradient throughout Florida were sampled for each assemblage. Forested flowing water wetlands were sampled for macrophytes only. The landscape development intensity index (LDI) was used to quantify the human disturbance gradient. In general, human disturbance in adjacent areas had the greatest impact on depressional herbaceous wetlands, followed by depressional forested wetlands. Forested flowing water wetlands (i.e., forested strands and floodplain wetlands) were less affected by local conditions, with most of their changes in wetland condition correlated with alterations at the larger watershed scale. Strong correlations between the FWCIs and LDI index scores suggest that changes in community structure can be detected along a gradient of human land use activities adjacent to wetland ecosystems.  相似文献   

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Patterns of malaria cases were compared between the department of Meta and the municipality of Puerto Gaitán, Colombia, to examine temporal change in malaria from 2005-2010. During this time frame in Meta the mean ratio was 2.53; in contrast, in Puerto Gaitán it was 1.41, meaning that a surprisingly high proportion of Plasmodium falciparum cases were reported from this municipality. A detailed analysis of data from Puerto Gaitán for 2009 and 2010 detected a significant difference (χ2, p < 0.001) in the distribution of plasmodia, with Plasmodium vivax more prevalent in 2009 and P. falciparum in 2010. Males had the highest number of cases but there was no difference in the distribution of cases between sexes and years. In both years, for both sexes, people 16-40 accounted for the majority of cases (58.9% in 2009; 60.4% in 2010). There were significant differences in the distribution of both P. vivax (χ2, p < 0.01) and P. falciparum cases (χ2, p < 0.05) by geographic setting (urban vs. non-urban) between years. Urban cases of both P. vivax and P. falciparum are recorded in this study for the first time in Puerto Gaitán, possibly the result of area wide displacement and migration due to armed conflict.  相似文献   

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This study evaluated the risk to human health from mercury exposure through fish consumption in three riverside populations: Children (CH, 2–15 years old), women of childbearing age (WCHA, 16–49 years old), and the rest of the population (RP) from the Urrá reservoir area, Colombia. Questionnaire-based surveys were used to collect data and information about the weekly amount of fish consumed (WAFC) and the relative importance of each fish species in the diet of the study participants. There were no significant differences in WAFC between population groups. CH recorded the highest weekly intake of total Hg (WIT-Hg) (0.6–55.4 μg/kg bodyweight/week), with significant differences (p < .05) from WCHA (0.2–26.7 μg/kg bw/w) and RP (0.1–23.6 μg/kg bw/w). A high percentage (90%) of estimated WIT-Hg values exceeded the provisional tolerable weekly intake (PTWI) established in order to protect the embryo and fetus. Results suggested that sensitive subgroups, such as pregnant women or those who may become pregnant and young children should limit or avoid consumption of certain fish of higher trophic levels due to their high total Hg (T-Hg) concentrations (up to 2.73 μg/g). In sum, the high values of WIT-Hg in children and women of childbearing age revealed a worrying situation, which should be reviewed carefully in order to prevent a potential public health crisis.  相似文献   

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Cryptococcus neoformans, the etiological agent of cryptococcosis, has been associated with avian droppings and certain trees in different countries, including Colombia. C neoformans environmental isolates were obtained in urban areas in Bogotá, Colombia, and the strains recovered were phenotypically characterized. Attempts to determine the ecological conditions (micro- and macroclimatic) possibly related to their habitat were also undertaken. Four hundred and eighty samples from bark, soil around trunk bases, and detritus inside hollows of 32 trees were collected in three urban areas during a 5-month period, as well as 89 avian droppings samples from different places. Of plant samples, 6.7% collected from nine tree species yielded C. neoformans var. gattii, serotype B strains in 99% of the cases, and C. neoformans var. grubii, serotype A in 1%. The yeast was more frequently recovered from bark than from soil or detritus inside hollows, and from trees with hollows or rotted wood rather than from trees in which birds nest. C. neoformans was present with higher frequency and density in the rainy season than in the dry season; we found that slightly higher temperature and humidity values of the microhabitat, as compared to those of the environment, favored fungal occurrence, but the phenological state of the tree did not. Of dropping samples, 7.9% yielded C. neoformans strains, all of them C. neoformans var. grubii, serotype A. The yeast was obtained more frequently from dry droppings than from moist ones, but neither the sunlight exposure nor the site of collection of samples was correlated with this occurrence. Population density was significantly higher in droppings than in tree samples. Under laboratory conditions, isolates of different serotype showed similar capsular sizes. Water content and pH ranges were wide and did not show any significant difference between positive and negative samples.  相似文献   

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The objective of this work was to establish, under experimental laboratory conditions, a colony of Lucilia sericata, Bogotá-Colombia strain, to build life tables and evaluate two artificial diets. This blowfly is frequently used in postmortem interval studies and in injury treatment. The parental adult insects collected in Bogotá were maintained in cages at 22°C±1 average temperature, 60%±5 relative humidity and 12 h photoperiodicity. The blowflies were fed on two artificial diets that were evaluated over seven continuous generations. Reproductive and population parameters were assessed. The life cycle of the species was expressed in the number of days of the different stages: egg = 0.8±0.1, larvae I = 1.1±0.02, larvae II = 1.94±0.16, larvae III = 3.5±0.54, pupae = 6.55±0.47, male adult = 28.7±0.83 and female adult = 33.5±1.0. Total survival from egg stage to adult stage was 91.2% for diet 1, while for diet 2 this parameter was 40.5%. The lifetime reproductive output was 184.51±11.2 eggs per female. The population parameters, as well as the reproductive output of the blowflies that were assessed, showed relatively high values, giving evidence of the continuous increase of the strain over the different generations and making possible its maintenance as a stable colony that has lasted for more than two years.  相似文献   

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ObjectiveTo determine the impact of pain on the quality of life in older adults and its association with functionality.Materials and methodsData was taken from SABE Bogota study. A cross-sectional study was carried out during 2012, interviewing 2,000 individuals of 60 years and older, as a probabilistic cluster and representative sample. The variable ‘presence of pain’ to was used to identify associations with sociodemographic factors, self-rated health, comorbidities, functional status, cognitive status, and quality of life. The latter was estimated using a visual analogue scale of the EuroQOL tool (EQ-VAS).ResultsThe majority of older adults were women (63.4%); the mean age was 71.17 years (SD = 8.05), with a higher frequency of individuals in the age group between 60 and 69 years (48%). When comparing groups with pain vs. no pain, significantly lower scores were found in the group with pain (P < .001) in both the functionality and quality of life EQ-VAS scales. The strongest associations with pain were: joint diseases (OR: 3.08 [2.24-4.23]), severe depression (OR: 2.80 [1.63-4.79]) and functional impairment of the Basic Activities of Daily Living (BADL) (OR: 2.45 [1.31-4.58]).ConclusionsPain negatively impacts the functional independence and the perception of the quality of life in older adults, predisposing them to adverse outcomes.  相似文献   

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The pulp and kernel oils from the fruit of this palm, exceedingly abundant in Paraguay, have long been used locally in the manufacture of soap. Kernels were formerly exported to Europe but now are entirely crushed in Paraguay and only the oil exported, principally to Argentina which normally takes 50 to 75% of the production.  相似文献   

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Wetland ecosystems have a high carbon storage potential as a result of high primary productivity and low decomposition rates dictated by water saturation. In the herbaceous wetlands of the Paraná River Delta, drainage and afforestation with poplars represents one of the dominant land uses. We explored the effects of these interventions on the volume and carbon storage of the young sedimentary soils of the region. At three sites we identified paired stands occupying similar landscape positions and soil types but subject to natural flooding and covered by natural herbaceous communities or drainage and flood control by dikes and covered by poplar plantations established 12, 17 and 19 years ago. Soil sampling at these sites revealed a reduction of the litter compartment (?86 %) and decreasing volume and porosity of its underlying mineral layer (0–10 cm in the wetland reduced to 0–4 cm in the plantation). Our comparisons of carbon storage accounted for these volumetric shifts by using accumulated mineral mass rather than depth as a reference, showing that tree plantations gained in the mineral soil (22 Mg C ha?1) almost as much as what they lost in the litter. These gains were particularly large at intermediate depths (4–43 cm in the plantations) were soil porosity remained unaffected and C was raised by 64 % explained by (1) the pulse of inputs from overlaying litter and organic layers subject to rapid decomposition and mobilization after drainage and (2) root colonization, since tree plantations had 75 % of their fine root biomass at these intermediate soil depths, whereas roots in the wetlands did not explore the mineral soil profile and were completely confined to the organic layer. A neutral C balance following wetland drainage and afforestation resulted from the opposing effects of aeration, favoring decomposition in the organic layer, root colonization and organic matter stabilization, favoring its accumulation in the mineral soil.  相似文献   

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Wetlands Ecology and Management - While coastal sand dunes are common in New Zealand, dune slack wetlands are one of the country's most rare and threatened ecosystems, containing a number of...  相似文献   

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