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131.
Many water-related problems are shared by most of the developing countries and the industrialized nations could be in position of offering aid in such problems. Water scarcity and access to safe water, water pollution, severe storms and floods, droughts, waterborne diseases and landslides and mud floods are the most commonly shared problems among developing nations. These problems were discussed in a workshop organized as part of the Fifth International Symposium on Environmental Hydraulics in 2008. The discussion included identification of actors both in the developing and developed nations (vgr. local and national governments, NGOs, universities, foundations and private and public research institutions), aid modalities such as education, technology transfer, technology development and direct investment as well as restrictions and barriers in the form of political and legal issues, economic limitations, cultural differences and geographic distances. Recommendations about how developed nations could help developing countries are issued.  相似文献   
132.
This study presents 30 cases of fetal isolated spina bifida aperta (SBA) to identify prenatal ultrasound findings that could predict the prognosis. Comparisons between surviving patients who had normal (group 1) and abnormal (group 2) post-natal neurological outcomes were made for three different prenatal signs, that is, site of vertebral lesion, presence and degree of ventriculomegaly and presence of talipes. The site of the lesion was the most significant outcome predictor, as high spinal dysraphisms were observed in 2 patients (2/7–28.6%) in group 1 and in 15 patients (15/19–79.0%) in group 2 (p = 0.03). The presence of fetal ventriculomegaly was associated with impaired post-natal neurological development, as it occurred in 4 patients (4/7–57.1%) in group 1 and in 18 patients (18/19–94.7%) in group 2 (p = 0.04). The presence of talipes did not significantly differ between the two groups. Patients with abnormal intellectual outcome (8/26–30.8%) had significantly greater (p = 0.018) lateral ventricle/hemisphere ratios (mean = 0.74, standard deviation = 0.13) than those with normal intellectual development (mean = 0.54, standard deviation = 0.18). Mean post-natal follow-up was at 23 months (standard deviation = 15 months). Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
133.
Constant environmental changes in oceanic and estuarine systems due to human activity in coastal zones require different tools and strategies for their study to be able to assess the health status of aquatic ecosystems. The Gulf of Mexico has a tremendous ecological importance because of its biological diversity. Baseline levels of blood metabolites and immune components were defined for wild tropical populations of Litopenaeus setiferus, an important shrimp species of the Gulf of Mexico. Osmotic pressure, oxy hemocyanin (OxyHc), glucose, proteins, cholesterol, lactate, and triacylglycerols (TAG) were used as indicators of physiological status; pro phenoloxydase (proPO) and phenoloxydase (PO) quantification of hemocytes, as well as respiratory burst, were used to assess the immunological status. Significant differences were observed in live weight of juveniles, males, and females of L. setiferus with mean values of 10.54, 35.05, and 40.33 g, respectively. A value of 460 mOsm/kg was recorded in the water where juveniles were sampled and 1,000 mOsm/kg in adult sampling zones. Consequently, the osmotic pressure of L. setiferus juveniles (718.02 mOsm/kg) was 22% lower than in adults (925 mOsm/kg); there were no differences between sexes. A significantly lower value in juvenile OxyHc was observed. This value was 24 and 16% lower than that observed in males and females, respectively. Hemolymph glucose, cholesterol, and triacylglycerol levels were not statistically different between shrimp stages, showing median values of 0.19, 0.32, and 0.39 mg/ml of glucose, cholesterol, and triacylglycerols, respectively. Hemocyanin was distributed normally in the juvenile–male population but not in females. A proportion between 52 to 81% of OxyHc of the total protein (OxyHc/Prot) was obtained for all stages. Digestive gland glycogen showed no normal distribution in juveniles and adults. Digestive gland glycogen was significantly higher in juveniles (median value of 2.64 mg/g) than in adults (median value of 1.58 mg/g). A higher value of lactate (0.11 mg/ml) was observed in juveniles than in males (0.09 mg/ml) and females (0.04 mg/ml). Granular cells (GC) corresponded to 36, 44, and 39% of the total hemocytes (TH) observed in juveniles, males, and females. ProPO showed no normal distribution in all stages. A high proPO activity was recorded in L. setiferus females that was 95% higher than in the juvenile–male group. Respiratory burst was divided into two groups, juveniles–males and females, and was distributed normally in both. Female respiratory burst values were 40 and 45% higher than those observed in the juvenile and male groups, respectively. There was an increment in OxyHc, proteins, PO, hemocytes, and respiratory burst with an increase in body weight. In contrast, the relationship of live weight to glucose, TAG, and proPO revealed no significant regressions. A significant decrease in cholesterol, glycogen, and lactate with an increase in body weight was also observed. We now have indicators of nutritional and immune status of juveniles and adults that can reveal changes in trophic relations and health at the population level. This will serve as a basis for using L. setiferus as environmental sentinels, as non-controversial and inexpensive models to evaluate the potential changes that human activities could exert on this important marine ecosystem.Communicated by P.W. Sammarco, Chauvin  相似文献   
134.
The effectiveness of a frugivore as a disperser of a plant is greatly determined by how fruits and seeds are handled in its mouth and its digestive tract. Although a number of studies have investigated the effect of avian ingestion on germination, we still know very little about the modifications to seeds during ingestion and the specific consequences on plant fitness. Here we investigate for the first time the different mechanisms by which germination patterns of seeds are modified following ingestion by frugivores. Specifically, we examine changes in seed mass, water content, permeability, seed coat thickness, texture, and resistance in two common Mediterranean fleshy-fruited plants, Phillyrea angustifolia and Myrtus communis, after ingestion by Eurasian Blackbirds, Turdus merula. We found a number of differences between the plant species: Phillyrea seeds lost mass, mainly due to water loss, and had thinner coats after gut passage, but Myrtus seeds did not. Seeds of both species showed increased permeability, while Myrtus seeds in particular became less resistant to breakage. No quantifiable changes in seed coat texture were detected in either species, although this trait was partly associated with differences in germination rate in Phillyrea. High intraspecific plant variation was found for most seed traits measured. Seed passage through birds' guts sped up germination in both species, especially in Myrtus. Increased permeability in seeds of both species following ingestion resulted in a higher germination rate. Moreover, seeds with thick coats (and in the case of Phillyrea, harder coats) germinated at a slower rate and produced seedlings that also grew more slowly, indicating a cost of coat thickness and/or hardness for seedling emergence. Results obtained here contribute to explaining the great heterogeneity in germination responses among and within plant species and the large variety of factors, both intrinsic and extrinsic to the plants, that influence such responses.  相似文献   
135.
136.
A wet air oxidation (WAO) process was applied to four selected pharmaceuticals (metoprolol, naproxen, amoxicillin, and phenacetin) individually dissolved in ultra-pure water, varying the temperature and oxygen pressure. Due to the moderate (amoxicillin) or low (metoprolol, naproxen, and phenacetin) efficiency found in the oxidation of these pollutants, a catalytic wet air oxidation (CWAO) process was then tested using a platinum catalyst supported on multi-walled carbon nanotubes (CNT). In this CWAO process, the pharmaceuticals were dissolved together in ultra-pure water and in four natural water matrices—a reservoir water, a groundwater, and two waters from different municipal wastewater treatment plants. On the basis of the measurements of their removals, a discussion is given of the influence of the main operating variables: the presence or absence of catalyst, type of catalyst (the synthesized Pt/CNT or a commercial Pt/AC), catalyst dosage (0.005–0.050 g), temperature (120–140 °C), and oxygen pressure (20–40 bar). In most experiments, the removals were in the sequence: amoxicillin > naproxen > phenacetin. In addition, total organic carbon (TOC) removal measurements were made of some of the natural waters tested.  相似文献   
137.
Valuing goods and services from open oceans provides arguments for the ocean's protection and plays an increasingly important role in debates on the use and management of natural resources. This paper identifies and estimates the monetary value of some of the most important goods and services provided by open oceans. The list of goods and services considered includes food production, raw materials, water supply, CO2 regulation, bioremediation of waste, biomass and biodiversity conservation. Therefore, not only values associated with productive uses are quantified but also values assigned to other biological ecosystem services. This paper constitutes a first attempt in the open ocean literature at evaluating services such as water supply, biomass and biodiversity conservation. To obtain their monetary value, different techniques, some not applied before in this area, have been used depending on the ecosystem service to be evaluated. As a general criterion we use the concept of net value added (revenues obtained from the services less incurred costs). Our methodology is illustrated by estimating the monetary values of goods and services provided by the open ocean ecosystem of Spain as defined by its exclusive economic zone. The total economic value obtained measures the contribution of oceans to overall welfare and it may be an important instrument in managing open ocean ecosystems and developing environmental policies in the future.  相似文献   
138.
This paper analyses both the processes of adoption and diffusion of the practice of using the chopped residues of pruning as mulch in the olive orchards of the Southern Spanish province of Granada, one of the major olive-producing areas in the world. Many olive groves in the area are located on steep areas where the risk of soil erosion is high. A majority of farmers have adopted no tillage, as an alternative to traditional tillage, combined with either vegetation soil covers or, more frequently, using the chopped pruning residues as mulch. The data used comes from a survey carried out in 2005 to 215 olive farmers. From farmers' responses we estimate a binomial probit model to identify some socio-economic and institutional factors related to the decision to use the practice of mulching on a regular basis. We also estimate several diffusion models that describe the spatial and temporal spread of mulching among farmers. Our results show that mulching using the pruning residues is adopted by 43% of the surveyed farmers. The diffusion process of this practice has been very intense since the middle nineties, and seems to have been based on the interactions among farmers in the area of study rather than in other external source of information. Some of the relevant identified factors that affect the probability of adoption of this practice are farmer's experience, the level of soil degradation in the farm or the continuity of farming by some relative.  相似文献   
139.
In recent years, significant advances have been made in business organization and management. The growing demands of clients as well as the globalization of world markets are among the many factors that have led to the establishment of systems of quality control and environmental management as a competitive strategy for businesses. When compared to other professional sectors, the construction sector has been slower to respond to environmental problems and to adopt Environmental Management Systems (EMS). In the world today the ISO 14001 standard is currently the main frame of reference used by construction companies to implement this type of management system. This article presents the results of a general study regarding the evaluation of the application of the ISO 14001 standard at civil engineering construction worksites in the Community of Madrid (Spain), specifically pertaining to requirement 4.4.1, Resources, roles, responsibilities, and authority. According to requirement 4.4.1, company executives should appoint people responsible for implementing the EMS and also specify their responsibilities and functions. The personnel designated for supervising environmental work should also have sufficient authority to establish and maintain the EMS. The results obtained were the following: - EMS supervisors did not generally possess adequate training and solid experience in construction work and in the environment. Furthermore, supervisors were usually forced to combine their environmental work with other tasks, which made their job even more difficult. - Generally speaking, supervisors were not given sufficient authority and autonomy because productivity at the construction site had priority over environmental management. This was due to the fact that the company management did not have a respectful attitude toward the environment, nor was the management actively involved in the establishment of the EMS. - Insufficient resources were allocated to the Environmental Management Unit. As a result, the application of EMSs in construction projects often appeared to be more of a formality, which was merely a way of maintaining the certification of the Environmental Management System. It was more a means of meeting the requirements for submitting a tender to contracting organisms rather than an indicator of any real commitment to improving the environmental performance of construction companies.  相似文献   
140.
Landfill sites have been the most common way of eliminating solid urban waste, as well as that of public and mining wastes. Landfill sites are a constant source of environmental pollution and wind is the most important contributing factor to air pollution, due to the erosion which it produces over the landfill site surfaces, transporting dust away from the source point. This causes serious risks for human health and general dirt in the surrounding areas of the landfill site. The result of dust air pollution produced in a landfill site is analysed through CFD3D (Computational Fluid Dynamics) by joining the LIDAR (Light Detection and Ranging) technique and Ansys CFX 10.0 software. The CFD simulations determine the wind velocity distribution on the landfill site surface and the different particle threshold friction velocities which determine the dust emission in multiphase simulations (air-particles). These simulations are validated from field data obtained in three measurement programmes for each type of landfill site surface treatment which has been studied. It was determined that the superficial landfill site treatment with the lowest air pollution is tall grass and bushes. The methodology used can be applied to the dust emission calculation in the design or evaluation of other landfill sites.  相似文献   
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