Modelling the Optimal Strategies of Fertiliser Application Using the Game-Theoretic Approach

This paper is a case study which describes the application of game-theoretic approach in resource management with specific emphasis on developing optimal strategies of phosphorus applications for soil fertilisation. The approach adopted allows resource managers to consider not only competitive strategies, which were treated as the Nash equilibrium game solutions, but also strategies which imply cooperation between farmers. These strategies were modelled as the cooperative Pareto optima of the game. The objective function of the game has been developed in order to reflect both economic advantages of phosphorus applications and the environmental losses associated with these applications expressed as dollar values. The paper presents algorithms for finding competitive and cooperative solutions of the game for the particular case when no time scheduling is included in the game parametrisation. The results obtained in the paper showed that the cooperative solutions lead to much lesser environmental impacts than that in the case of non-cooperative strategies.     

Prenatal diagnosis,prediction of outcome and in utero therapy of isolated congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) can be associated with genetic or structural anomalies with poor prognosis. In isolated cases, survival is dependent on the degree of lung hypoplasia and liver position. Cases should be referred in utero to tertiary care centers familiar with this condition both for prediction of outcome as well as timed delivery. The best validated prognostic indicator is the lung area to head circumference ratio. Ultrasound is used to measure the lung area of the index case, which is then expressed as a proportion of what is expected normally (observed/expected LHR). When O/E LHR is < 25% survival chances are < 15%. Prenatal intervention, aiming to stimulate lung growth, can be achieved by temporary fetal endoscopic tracheal occlusion (FETO). A balloon is percutaneously inserted into the trachea at 26–28 weeks, and reversal of occlusion is planned at 34 weeks. Growing experience has demonstrated the feasibility and safety of the technique with a survival rate of about 50%. The lung response to, and outcome after FETO, is dependent on pre-existing lung size as well gestational age at birth. Early data show that FETO does not increase morbidity in survivors, when compared to historical controls. Several trials are currently under design. Copyright © 2008 John Wiley & Sons, Ltd.     

Degradation of pharmaceuticals in wastewater matrices through solar light-driven photocatalyst prepared from petrochemical waste

Environmental Science and Pollution Research - Pharmaceuticals, such as dipyrone (DIP), paracetamol (PCT), and propranolol (PPN), are widely used analgesics and beta-blockers with the greatest...     

Trace elements: water-sediment interactions in tropical rivers

Environmental Science and Pollution Research - This research aimed to determine the water-sediment interaction (partition coefficient Kd) of trace element (Cd, Cu, total Cr, Pb, and Zn) in tropical...     

Influence of Brazilian herbal regulations on the use and conservation of native medicinal plants

For decades, several native medicinal species have been used by the pharmaceutical industry in Brazil to create commercial products. In 1995, the Ministry of Health, following the recommendations of the World Health Organization, established herbal regulations (RDC 17) in order to improve the quality of such products. In fact, only plant species with conclusive results from pharmacological and toxicological studies can be used for creating medicines. In this study, we evaluated the consequences of RDC 17 on the use and conservation of native medicinal plants by comparing the plant material used by six companies in 1995/1996 and 10 years later (2005/2006). Eighty-three different species were used in 1995/1996, 50 of them native (60.2%), 16 exotic (19.3%), and 17 imported (20.5%). In 2005/2006, 44 species were used by the companies and only 19 (43.2%) were native. The category of plant material that saw the largest decrease in use was roots, and in 2005/2006 leaves were more used. The study shows a strong reduction in the collection of native species signalizing the importance of herbal regulations on their conservation. It also points to the need for pharmacological and toxicological studies of the Brazilian native medicinal flora, as well as studies on their ecology and conservation.     

Distribution coefficients of potentially toxic elements in soils from the eastern Amazon

The solid-solution distribution or partition coefficient (Kd) is a measure of affinity of potentially toxic elements (PTE) for soil colloids. Kd plays a key role in several models for defining PTE guideline values in soils and for assessing environmental risks, and its value depends on edaphic and climatic conditions of the sites where the soils occur. This study quantified Kd values for Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn from representative soil samples from Brazil’s eastern Amazon region, which measures 1.2 million km². The Kd values obtained were lower than those set by both international and Brazilian environmental agencies and were correlated with the pH, Fe and Mn oxide content, and cationic exchange capacity of the soils. The following order of decreasing affinity was observed: Pb?>?Cu?>?Hg?>?Cr?>?Cd?≈?Co?>?Ni?>?Zn.     

Changes in Microbial Community Structure and Soil Biological Properties in Mined Dune Areas During Re-vegetation

The aim of this study was to describe the impact of re-vegetation on the restoration of microbial community structure and soil microbiological properties in sand dunes that had been affected by mining activity. Soil samples were collected during the dry and rainy seasons from a chronosequence (1, 9, 21 years) of re-vegetated dunes using a single preserved dune as a reference. The composition of the fatty acid methyl esters and soil microbial properties were evaluated. The results showed that the changes in microbial community structure were related to seasonal variations: biomarkers of Gram-positive bacteria were higher than Gram-negative bacteria during the dry season, showing that this group of organisms is more tolerant to these stressful conditions. The microbial community structure in the natural dune was less affected by seasonal variation compared to the re-vegetated areas, whereas the opposite was observed for microbiological properties. Thus, in general, the proportion of saprobic fungi was higher in the natural dune, whereas Gram-negative bacteria were proportionally more common in the younger areas. Although over time the re-vegetation allows the recovery of the microbial community and the soil functions, these communities and functions are different from those found in the undisturbed areas.     

Selective aggressiveness in European free-tailed bats (Tadarida teniotis): influence of familiarity,age and sex

Bats are highly social mammals that often form large groups and represent good models to test the role played by individual status in shaping social relationships. Social cohesion relies on the ability of group and individual recognition, which is mediated by a range of sensorial cues. In this study, we selected the European free-tailed bat Tadarida teniotis as a model species to test the effects of familiarity, sex and age on aggressiveness and mutual tolerance. We hypothesize that T. teniotis is able to recognize group members and exhibit selective aggressiveness, and thus we predict fewer aggressive events and more amicable encounters between colony mates than between strangers. As female bats are generally more sociable and perform prolonged parental care to juveniles even after weaning, we hypothesize that sex and age of bats have significant influences on aggressive behaviours and thus predict that females will perform more amicable behaviours than males and that adults of both sexes will be less aggressive towards juveniles. Our results confirm that T. teniotis is able to discriminate between familiar and stranger individuals, showing higher rates of aggressive behaviours towards the latter. Females are more prone to exhibit amicable behaviours, particularly during same-sex interactions, while males show higher level of aggressiveness. Juveniles are subjected to fewer aggressive behaviours by adults of both sexes. Familiarity appears crucial for T. teniotis in determining the degree of aggressiveness during social interactions but the rate of aggressive events is also influenced by intrinsic individual factors such as sex and age.     

Prehibernating aggregations of Polistes dominulus: an occasion to study early dominance assessment in social insects

At a very early age several mammals establish a first dominance hierarchy, which often persists into adulthood. Social wasps offer an excellent opportunity to study such a phenomenon in insects. Indeed, foundresses of several paper wasps meet in clusters to hibernate from September to March. In spring, wasps found new associative nests where linear hierarchies occur. In the first phase of hibernation, clustering Polistes dominulus wasps show most of the social interactions occurring on the nest 6 months later. At the emergence from diapause, some females already show some behavioral and physiological traits typical of dominant individuals. Here, we investigated the significance of the interactions in the autumnal clusters. We demonstrated that in a given pair, it is more likely that the dominant wasp in autumn becomes the alpha female in spring after the nest foundation phase occurred. Moreover, we showed that dominant females in clusters have both larger body size and ovaries. As ovarian development mainly depends on the social context, our findings seem to indicate that social factors affect the tendency to dominate in aggregations. Furthermore, we suggest that some females may reinforce their physiological status by dominating in clusters, thus increasing the probability to become dominant in spring.     

Possible chemical causes of skeletal deformities in grey heron nestlings (Ardea cinerea) in North Nottinghamshire, UK

Dead and deformed grey heron (Ardea cinerea) chicks were reported at a large heronry in North Nottinghamshire, UK between 1996 (when systematic visits to the heronry started) and 2002. Many of the birds died for no obvious reason but deformities in others included multiple fractures of the tarsus and tibia and metacarpal bones (angel wings). This study aimed to investigate possible chemical causes of these deformities. Analysis of eggs and nestling tissue for a range of metals showed no levels of concern and no significant differences between unaffected and deformed birds. However, the levels of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) detected in affected heron nestlings in 2002 and in eggs taken from nests in 2003 were sufficiently high to suggest that this may be the underlying cause of the deformities, possibly due to effects on deposition of calcium in bone. Further work is underway to identify where the parent birds of the affected nestlings are feeding and identify the possible source of the pollution.