11 |
Sustainable Control of <em>Ascaris Lumbricoides</em> (Worms) in a Rural, Disease Endemic and Developing Community: A Systems ApproachGray, Monica Annmarie 30 June 2008 (has links)
Parasitic infections, inadequate sanitation, and poor nutrition represent major etiologies that operate in synergy to cause some of the world's most disabling diseases. Citizens of developing nations, especially children living in rural areas, are the most affected. Current research and subsequent interventions have attempted to solve these issues using vertical interventions aimed at minimizing specific health outcomes. This approach does not consider the interaction among causes and the interrelationship between human beings and their environment. Challenges solved in this manner often fail to produce sustainable results or worse, create new problems.
This project proposed the systems approach framework to address these challenges. The systems thinking dynamical modeling software, STELLA®, was used to model the conditions that promoted and/or hindered Ascaris lumbricoides and other gastrointestinal parasitic diseases in the rural developing community of Paquila, Guatemala. The interventions chosen were: administration of anti - helminthic drugs, supplying protein nutrition, and an excreta management system that allowed for effluent recycling to crop production. A new design for a Solar Latrine was proposed and the solar heating and microbial deactivation processes were modeled using the commerically available, Finite Element Method software COMSOL®.
From the simulations, disease eradication was most likely to occur when at least 50% of the host population were treated every 3 months for 2 years or more with an anti - helminthic drug of 94% efficacy or better, latrine coverage and usage were at least 70%, and nutrition was provided at about 1.1 g protein per kg (human mass) per day. Given the climatic conditions in Paquila and the proposed latrine design, sustained treatement temperatures of up to 65°C were possible in the fecal materail and with a minimum of 1 month (4 months maximum) retention time, it was concluded that the resulting humanure would meet US EPA Class A Biosolids microbial requirements.
|
12 |
Études géoarchéologique et archéopalynologique d'une fosse d'aisances datant du XIXe siècle sur le site Anderson (CeEt-950), Limoilou, QuébecPouliot, Guillaume 26 April 2024 (has links)
Les fouilles archéologiques du site Anderson (CeEt-950), à Limoilou, à Québec, ont mis au jour une fosse d'aisances jadis utilisée par les familles Anderson et Pitl au cours du XIXe siècle. S'inscrivant dans un projet pluridisciplinaire, cette étude utilise des approches de la géoarchéologie intra-site (stratigraphie, sédimentologie et micromorphologie des dépôts archéologiques) et l'archéopalynologie pour acquérir des connaissances sur l'environnement local du site Anderson et pour améliorer notre compréhension de l'utilisation et de la gestion de la fosse afin de reconstituer le régime alimentaire, l'hygiène et l'appartenance sociale des occupants du site. Les résultats montrent que la fosse d'aisances a été aménagée dans une ancienne plaine alluviale (plaine de la rivière Saint-Charles), laquelle fut possiblement colonisée par une végétation herbacée. Pendant l'utilisation de la fosse, la flore locale était dominée par les chénopodiacées et/ou amaranthacées et les poacées, ce qui atteste d'un cortège floristique rudéral pouvant être lié à l'aménagement du site et aux champs avoisinants. Les dépôts de la fosse sont caractérisés par une matrice organo-minérale incorporant des microartefacts, des restes végétaux, des fragments d'os, des œufs de parasites et de la chaux. Ces restes témoignent que les Anderson ont jeté des déchets domestiques et alimentaires ainsi que des matières fécales avant d'assainir leurs immondices. Par la suite, les Pitl ont continué à remplir la structure avec des matières résiduelles avant son comblement définitif. La micromorphologie a démontré que les dépôts ont été affectés par des fluctuations de la nappe phréatique et par la compaction des sédiments organo-minéraux basaux, associés à la famille Anderson. Les deux familles auraient consommé des produits transformés (pain, etc.), des produits dérivés (confiture, sirops, etc.), des fruits et des légumes cultivés ou achetés pour répondre à des besoins alimentaires, médicinaux et probablement cosmétiques indiquant ainsi une continuité dans les habitudes de consommation. En somme, l'application conjointe de la géoarchéologie intra-site et de l'archéopalynologie dans le contexte de la fosse d'aisances étudiée a permis de reconstituer l'alimentation des usagers, le mode de gestion de la fosse et retracer l'environnement local du site Anderson.
|
13 |
Impact of wildfire on the spotted-tailed quoll Dasyurus maculatus in Kosciuszko National ParkDawson, James Patrick, Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2005 (has links)
A population of spotted-tailed quolls Dasyurus maculatus was studied for three years (2002-2004) in the lower catchment of the Jacobs River, in the Byadbo Wilderness Area of southern Kosciuszko National Park, south-eastern New South Wales, Australia. Survey and monitoring of quoll latrine sites and prey populations, dietary analysis and live-trapping was carried out for one year before and two years after the widespread wildfires of January 2003, which had a very high impact on the study area. Survey for spotted-tailed quoll latrine sites was successful in locating a total of 90 latrine sites in the Jacobs River study area over the three years of the study. These were found throughout all parts of the topography among large, complex granite outcrops and along rocky sections of riparian habitat. After the fire in 2003, lower numbers of latrines were in use than observed pre-fire, and there was a lower level of usage (number of scats) of individual latrines. Continued monitoring in 2004 revealed that many latrines that had become inactive in 2003 following the fire were re-activated in the second breeding season following fire. 1466 spotted-tailed quoll scats were collected from latrines and live-trapped quolls over the three years of the study. Hair analysis from scats identified twenty-two different species of mammal in the diet of the spotted-tailed quoll from the Jacobs River study area, representing the majority of all prey identified (98.5% occurrence) and contributing almost all of the biomass consumed (99.6%). Medium-sized mammals were the most important prey category, followed by small mammals, large mammals (most likely taken as carrion) and non-mammalian prey (birds, reptiles, insects and plants). Brushtail possums were the most important single prey item by both frequency of occurrence and percentage biomass in all years, followed by lagomorphs (rabbits and hares), Rattus spp., and swamp wallabies. There was a significant difference in the composition of the diet by major prey category across the years of the study as a result of the fire, indicated by a shift in utilisation of food resources by quolls in response to significant changes in prey availability. Monitoring of prey populations revealed that brushtail possums, lagomorphs and bandicoots were all significantly less abundant in the study area in the winter directly following the fire, followed by a significant increase in abundance of lagomorphs, but not of possums, in the second winter after the fire. Quolls adapted well to this altered prey availability. While there was a significant decrease in occurrence of brushtail possum in scats after the fire, significantly more scats contained hair of lagomorphs, to the point where almost equal proportions of lagomorphs and possum hair occurred in scats by the winter of 2004. Other fire-induced changes to the diet were evident, such as a significant drop in the occurrence of small mammals in scats for both winters after the fire, and a peak in occurrence of large mammals in the winter directly following the fire that strongly suggests there was a short-term increase in the availability of carrion. A large, high-density population of spotted-tailed quolls was live-trapped and marked during the winter breeding season of 2002. Twenty-two quolls (13 male and 9 female) were present in the study area in 2002, and subsequent trapping over the 2003 and 2004 winter breeding seasons following the fire revealed that the high-intensity wildfire did not result in the extinction of the local population. There was evidence of a small, short-term decline in the number of quolls present in the study area in the 2003 breeding season, with 16 individual quolls captured. Males were outnumbered two-to-one by females, due either to mortality or emigration. Trapping in 2004 showed a recovery of the population to numbers exceeding that observed prior to the fire, with 26 individuals captured (16 male, 10 female), most likely as a result of immigration. There was some evidence that recruitment of young from the post-fire breeding season in 2003 was reduced because of the fire. This study took advantage of an unplanned wildfire event to monitor the response of a population of spotted-tailed quolls and their prey. In this regard it was fortuitous since it has been recognised that the use of replicates and controls in the study of the impacts of wildfire on such species is likely to be logistically impossible. Consequently, the effects of fire on forest and woodland fauna such as the spotted-tailed quoll are poorly understood, with many authors expressing concern that, potentially, wildfires are likely to be highly detrimental to resident quoll populations. The results of this study, however, concur with the few other studies in which forest mammal populations have been monitored before and after wildfire in suggesting that wildfires may not be as destructive to fauna as that imagined. The results of this work will provide information to assist in the preparation of management strategies for the species, such as recovery plans, as well as information for land managers preparing management plans, including fire management plans, for habitats in which spotted-tailed quolls are found throughout their range.
|
14 |
LIFE HISTORY AND CHEMOSENSORY COMMUNICATION IN THE SOCIAL AUSTRALIAN LIZARD, EGERNIA WHITIIBellamy, Robyn Lyle, robyn.bellamy@flinders.edu.au January 2007 (has links)
ABSTRACT
Social relationships, habitat utilisation and life history characteristics provide a framework which enables the survival of populations in fluctuating ecological conditions. An understanding of behavioural ecology is critical to the implementation of Natural Resource Management strategies if they are to succeed in their conservation efforts during the emergence of climate change. Egernia whitii from Wedge Island in the Spencer Gulf of South Australia were used as a model system to investigate the interaction of life history traits, scat piling behaviour and chemosensory communication in social lizards.
Juveniles typically took ¡Ý 3 years to reach sexual maturity and the results of skeletochronological studies suggested longevity of ¡Ý 13 years. Combined with a mean litter size of 2.2, a pregnancy rate estimated at 75% of eligible females during short-term studies, and highly stable groups, this information suggests several life history features.
Prolonged juvenile development and adult longevity may be prerequisite to the development of parental care. Parental care may, in turn, be the determining factor that facilitates the formation of small family groups. In E. whitii parental care takes the form of foetal and neonatal provisioning and tolerance of juveniles by small family or social groups within established resource areas. Presumably, resident juveniles also benefit from adult territorialism. Research on birds suggests that low adult mortality predisposes cooperative breeding or social grouping in birds, and life history traits and ecological factors appear to act together to facilitate cooperative systems.
E. whitii practice scat piling both individually and in small groups. Social benefits arising from signalling could confer both cooperative and competitive benefits. Permanent territorial markers have the potential to benefit conspecifics, congenerics and other species. The high incidence of a skink species (E. whitii) refuging with a gecko species (N. milii) on Wedge Island provides an example of interspecific cooperation. The diurnal refuge of the nocturnal gecko is a useful transient shelter for the diurnal skink. Scat piling may release a species ¡®signature¡¯ for each group that allows mutual recognition.
Scat piling also facilitates intraspecific scent marking by individual members, which has the potential to indicate relatedness, or social or sexual status within the group. The discovery of cloacal scent marking activity is new to the Egernia genus. E. Whitii differentiate between
their own scats, and conspecific and congeneric scats. They scent mark at the site of conspecific scats, and males and females differ in their response to scent cues over time. Scat piling has the potential to make information concerning the social environment available to dispersing transient and potential immigrant conspecifics, enabling settlement choices to be made.
This thesis explores some of the behavioural strategies employed by E. whitii to reduce risks to individuals within groups and between groups. Scents eliciting a range of behavioural responses relevant to the formation of adaptive social groupings, reproductive activity, and juvenile protection until maturity and dispersal are likely to be present in this species. Tests confirming chemosensory cues that differentiate sex, kin and age would be an interesting addition to current knowledge. The interaction of delayed maturity, parental care, sociality, chemosensory communication and scat piling highlights the sophistication of this species¡¯ behaviour.
An alternative method for permanently marking lizards was developed. Persistence, reliability and individual discrimination were demonstrated using photographic identification and the method was shown to be reliable for broad-scale application by researchers. Naturally occurring toe loss in the field provided a context against which to examine this alternative identification method and revealed the need to further investigate the consequences of routine toe clipping, as this practice appears to diminish survivorship.
|
Page generated in 0.0641 seconds