Intermittent fevers caused by Plasmodium parasites have been known for millennia, and have caused untold human suffering. Today, millions of people are afflicted by malaria each year, and hundreds of thousands die. Historically, the most successful synthetic antimalarial drug was chloroquine, as it was safe, inexpensive, and highly efficacious. However, plasmodial resistance to chloroquine now greatly limits its utility. Previously in our laboratories it has been shown that attachment of a "reversal agent moiety" to the side chain of chloroquine can result in the restoration of activity against chloroquine-resistant strains of P. falciparum malaria. In the first part of the work presented here, a study has been made of the importance of the quinoline ring substitution pattern to the activity of such reversed chloroquines. The compounds presented here include those bearing a substituent in the 2-, 5, 6-, 7-, and/or 8- position, and include those with chloro, bromo, iodo, fluoro, nitro, trifluoromethyl, methyl, and methoxy substituents. For reversed chloroquines, 2-, 5-, and 8- substituents have been found to decrease in vitro antiplasmodial activity against P. falciparum relative to 7-chloro substitution, whereas 6- and 7- substituted compounds with various substituents have in many cases similar activity to that of 7-chloro substituted compounds. Little difference has been observed between 6- and 7- substitution, or between chlorine and a methyl group in position 6. In most cases these effects on activity are directionally similar to those observed for chloroquine analogs without an attached reversal agent, but the magnitude of the effect is generally smaller, suggesting that the activities of reversed chloroquines are less affected by modifications to the quinoline ring system than is true for chloroquine analogs without an attached reversal agent. The second portion of this work presents an asymmetrical bis-quinoline (PL241) that is highly active against P. falciparum malaria, with an IC50 of less than 0.1 nM for all strains tested. Mechanistic studies have been performed in which the substitution patterns of the two quinoline rings of PL241 are modified in ways that indicate that either ring system is equally capable of participating in the antimalarial activity of these compounds. The excellent in vitro antiplasmodial activity of PL241 makes this a compound of great interest for further development as a potential antimalarial drug. In the third part of this work, a survey has been made of antimalarial treatments recommended in the European medical literature from the time of Pliny the Elder (active in the first century A.D.) through the advent of modern malaria chemotherapy in the early twentieth century. In the fifteen primary sources utilized in this study, 251 distinct substances - primarily plants - were identified as having likely been used in the treatment of malaria. Of the 38 substances that were described in three or more sources, at least fifteen have been examined by other workers for antiplasmodial activity; in many cases, they were found to have antiplasmodial activity in vitro or in vivo. However, the majority of the phytotherapies for malaria identified in this project have not yet been tested against Plasmodium species, and may provide valuable leads in the search for new compounds active against drug-resistant malaria.

Changing lake conditions due to cyanobacterial harmful algal blooms (CyanoHABs) have prompted inconsistent and evolving management and recreational use of Southern Illinois University’s Campus Lake. The objective of this study was to address the need for understanding lake-user demographics, CyanoHAB and Campus Lake perception, and support for potential Campus Lake programs. I accomplish this by implementing and summarizing Lake-User and Student Questionnaires, applying an Experience Use History (EUH) method to categorize respondents, and utilizing university resources to understand the effects of environmental variables on perception of Campus Lake. Respondent demographics fit typical leisure participation, where most lake users were encountered walking/jogging. Students participating in the Campus Lake Sustainable Eco-Recreation program self-report a higher familiarity with lake water quality and CyanoHABs than non-participants. There was little evidence of Nature Deficit Disorder, and no difference in support for hypothetical management action options based on this factor. Backwards stepwise regression analysis of stated choice management action support for two hypothetical lake management plans resulted in a proscriptive outcome. EUH results modeled expected sociodemographic characteristics, and Beginners showed support for increasing recreation activity to support hypothetical lake management. Perceptions of Campus Lake water quality status were best correlated with visible algal growth, Temperature-Heat-Solar radiation-Wind index, and mean prior 24 hr relative humidity variables. This Campus Lake survey should be used to diversify lake accessibility and recreation programs targeted towards minority and special interest groups. Surveying of natural resource user perceptions, especially in the case of shifting quality, is a valuable tool to monitor and capitalize on public interest.

<p>The conventional view on the Kalahari in southern Africa expresses that the area is unsuitable for livestock herding. For this reason, it is argued that livestock herders avoided the Kalahari in the past and were only able to establish themselves in the later half of the twentieth century, when deep-reaching boreholes were introduced in the area. An effect of this concept was that the archaeological record of pastoralists in the Kalahari either was perceived as non-existent or received little attention from scientific enquiry.</p><p>Based on an archaeological survey in the Kalahari of the northeastern part of Namibia, the purpose of this study is to construct an alternative approach to the archaeology of livestock herding. The aim is to contribute to a better understanding of the areas unrecorded land-use history. </p><p>I depart from the notion that the main ecological constraint for dryland pastoralism is the availability of dry season water and fodder resources. For this reason, the fundamental basis for a pastoral land-use system is places that contain dry season resources. By reviewing recent ecological research, historical and anthropological accounts and previous archaeological research, I establish a link between livestock herders’ procurement of dry season key resources and the practice of digging wells. The link can be motivated from the pastoral ambition of accumulating livestock and high water requirements in the restrained dry season. On this basis, I suggest that artificial wells are useful indicators of pastoral land use in the Kalahari. </p><p>The most crucial task for the study is to address the archaeological visibility of pastoral well sites. By a research approach integrating the theoretical understanding of pastoralism and a methodology including ecology, archaeology, history and the knowledge of the people who keep livestock in the region today, the archaeological survey revealed 40 well sites, including nearly 200 well structures that have all been used for watering livestock. </p><p>However, it would be unfortunate if a study of pastoral wells would solely address the ecological foundation and the archaeological visibility of pastoralism. I suggest that the wells signify the labour of peoples with common or separate histories, with or without own herds, but probably talked about in relation to herds. I will also argue that the wells can be used for tracking and reconstructing a pastoral land-use system that predated the colonial era. Furthermore, the wells can be used to identify changes of the land-use that took place during the twentieth century, which involved that livestock herding was more or less abandoned in large parts of northwestern Kalahari. </p><p>The study surmises that the critical historical perspective is valuable for development projects and conservationist interventions active in the region, especially in the light of the recent trends in the dryland ecology, which shows a larger appreciation for the indigenous understanding of the management of dryland ecosystems. With modifications, the developed approach can be applicable for land-use historical research elsewhere in southern Africa.</p>

The conventional view on the Kalahari in southern Africa expresses that the area is unsuitable for livestock herding. For this reason, it is argued that livestock herders avoided the Kalahari in the past and were only able to establish themselves in the later half of the twentieth century, when deep-reaching boreholes were introduced in the area. An effect of this concept was that the archaeological record of pastoralists in the Kalahari either was perceived as non-existent or received little attention from scientific enquiry. Based on an archaeological survey in the Kalahari of the northeastern part of Namibia, the purpose of this study is to construct an alternative approach to the archaeology of livestock herding. The aim is to contribute to a better understanding of the areas unrecorded land-use history. I depart from the notion that the main ecological constraint for dryland pastoralism is the availability of dry season water and fodder resources. For this reason, the fundamental basis for a pastoral land-use system is places that contain dry season resources. By reviewing recent ecological research, historical and anthropological accounts and previous archaeological research, I establish a link between livestock herders’ procurement of dry season key resources and the practice of digging wells. The link can be motivated from the pastoral ambition of accumulating livestock and high water requirements in the restrained dry season. On this basis, I suggest that artificial wells are useful indicators of pastoral land use in the Kalahari. The most crucial task for the study is to address the archaeological visibility of pastoral well sites. By a research approach integrating the theoretical understanding of pastoralism and a methodology including ecology, archaeology, history and the knowledge of the people who keep livestock in the region today, the archaeological survey revealed 40 well sites, including nearly 200 well structures that have all been used for watering livestock. However, it would be unfortunate if a study of pastoral wells would solely address the ecological foundation and the archaeological visibility of pastoralism. I suggest that the wells signify the labour of peoples with common or separate histories, with or without own herds, but probably talked about in relation to herds. I will also argue that the wells can be used for tracking and reconstructing a pastoral land-use system that predated the colonial era. Furthermore, the wells can be used to identify changes of the land-use that took place during the twentieth century, which involved that livestock herding was more or less abandoned in large parts of northwestern Kalahari. The study surmises that the critical historical perspective is valuable for development projects and conservationist interventions active in the region, especially in the light of the recent trends in the dryland ecology, which shows a larger appreciation for the indigenous understanding of the management of dryland ecosystems. With modifications, the developed approach can be applicable for land-use historical research elsewhere in southern Africa.

<p>Land use histories affect the rate and pattern of soil nutrients at regional and global scale. However, former studies have rarely focused on soil trace elements (B, Mn, Zn, Cu and Fe). In this study, we aimed at the long-term biogeochemical cycling pattern and spatial heterogeneity of soil trace elements in response to land use changes. We conducted experiment at Calhoun experiment forest in SC and surrounded relic hardwood forest, cultivated land and secondary pine forests with contrasting land use histories in a statistically rigorous and spatially explicit design. Our first study indicated that spatial heterogeneity is greatly reduced in many soil properties by agricultural practices, but that successional forest growth on previously cultivated soils re-structures heterogeneity of soil properties within a few decades. We document cases in which land use alters both the soil property's central tendencies and their heterogeneity (C, N, CN, Ca, K), and cases in which changes are apparent in central tendency but much less so in their heterogeneity (Db). In our second study, samples of the upper 0.6-m mineral soil archived in 1962 and 1997 revealed three cycling patterns: 1) Extractable B and Mn were significantly depleted because tree uptake of B and Mn from mineral-soil greatly outpaced resupplies from atmospheric deposition, mineral weathering, and deep-root uptake. 2) Extractable Zn and Cu changed little during forest growth, indicating that nutrient resupplies kept pace with accumulations by the aggrading forest. 3) Oxalate-extractable Fe increased substantially during forest growth, by about 10-fold more than accumulations in tree biomass. This study indicated that forest Fe cycling is qualitatively different from that of other macro- and micro-nutrients. Thirdly, our results revealed that long-term cultivation substantially diminished the activity of soil iron oxides relative to forest growth. Forest Fe cycling is derived from mineral soil weathering, which suggests a need to explore the underlying mechanisms by which bioturbation (e.g.earthworms) mediates transformations of iron bioavailability and oxidation of organic matter in soils. Overall, the wide range of responses to land use changes among the ecosystem's trace elements and other biogeochemical features illustrates the great dynamics of the soil system over time scales of decades to centuries.</p> / Dissertation

Historic land uses impose discernable legacy effects that may influence ecosystem function, a concern of particular importance in actively managed landscapes. In recent history (ca. 150 years) tree and shrub abundance has increased at the expense of native grasses in savannas and grasslands. The magnitude and patterns of change are spatially heterogeneous, highlighting the need for analytical approaches spanning multiple spatial scales, from individual plants to patches to landscapes. The overarching goal of this dissertation was to explore long-term dynamics associated with woody plant encroachment with aerial photography and field studies to examine cover, density, soils and land use history at the Santa Rita Experimental Range.The first study characterized patterns in woody cover change on contrasting soils over 60 years using aerial photography. Woody patch dynamics revealed encroachment and stabilization phases in woody plant proliferation. Soil properties reflected the rate at which uplands reached a dynamic equilibrium, but not the endpoint (ca. 35% cover). Fluctuations around dynamic equilibrium reflected net change in patch growth and acquiescence combined with colonization and mortality. Efforts to characterize changes in land cover will require patch-based assessments beyond coarse estimates of percent cover.The second study capitalized on historic field measurements of shrub canopies to validate estimates of shrub cover derived from the earliest aerial photography, quantified detection limitations of 1936 aerial photographs for mapping shrub cover, assessed species-specific contributions to percent cover, and translated detection limitations to proportions of velvet mesquite (Prosopis velutina var Woot.) biomass missed with 1930s aerial photography.The third study was a field-based approach investigating how livestock grazing influenced mesquite cover, density, biomass, and stand structure over 74 years. The study supplemented traditional statistical analysis of grazing effects with methods quantifying spatial autocorrelation structure of mesquite density by grazing treatment. The outcome re-affirmed the supposition that mesquite cover may be dynamically stable at ca 30%, and revealed that livestock grazing slowed the shrub encroachment process from 1932 to 2006, counter to expectation. Results indicate that shrub growth trajectories persist long-term. Overall, this work affirms the importance of land use legacies and long-term perspectives in rangeland shrub dynamics.

"July 1994". / Thesis (PhD) -- Macquarie University, School of History, Philosophy and Politics, 1995. / Bibliography: leaves 400-462. / Women and substance use. An introduction -- Women and substance use from a different perspective. Feminist theory and methodology -- 'Fallen angels and moral heroines'. The historical construction of women and substance use -- 'When the normal is pathological and the pathological is normal'. Psychological explanations of women and substance use -- 'A foot in both camps'. Psychosocial explanations of women and substance use -- 'Violence as symptom and cause'. The role of substance use in the social control of women -- 'Breaking all the rules'. Legal responses to women and drugs-related crime -- 'When liberation is no liability'. Women as consumer targets -- 'A nice girl like you'. Women and substance use treatment -- Conclusion -- Bibliography. / In Australia today, as in many other comparable societies, women's use of alcohol and other legal drugs is not circumscribed as it has been in the past. On the face of it, this suggests that there has been a major shift in social attitudes towards use of certain substances by women in line with changes to women's social position that occurred in the last few decades. Despite these changes, however, or perhaps because of them, women's use of alcohol and other drugs still attracts different attitudes and social responses when compared to similar behaviour in men. -- The objective of this research is to investigate the reasons why women's substance use behaviour is viewed differently from that of men's, how this has come about, why it is so culturally pervasive, and what are the effects for women. It has involved exploring how the meanings attached to women's use of certain chemical substances have been socially and historically constructed through scientific discourse, and how these meanings continue to be reproduced, reinforced and legitimated within other interlocking discourses. They are reflected too in cultural images as well as in popular attitudes, held by both women and men. -- The research has been undertaken using a 'woman-centred' approach, within the framework of feminist analysis. Such approach provides an alternative way of understanding women's experience with substance use. / Mode of access: World Wide Web. / [9], 462 leaves

Diss. Alnarp : Sveriges lantbruksuniv., 2003.

Illinois has no official parameters for old-growth oak-hickory (Quercus-Carya) forests despite oak-hickory being the historically dominant ecosystem in the forested parts of Illinois (Fralish, 1997; Thompson & Dessecker, 1997). The purpose of this study was to better understand the characteristics of old-growth oak-hickory stands, as well as make management recommendations for preserving the integrity of old-growth forests and shifting second-growth stands to old-growth status. Stand structure analysis was conducted in June and July of 2022 on an old-growth oak-hickory stand (Otey-Grisley Nature Preserve) and nearby second-growth oak-hickory stand (Grisley Woods Land and Water Reserve) near Pittsburg, Illinois using dendrochronology, various stand composition analyses, and floristic assessments to compare the two forests across multiple nodes of inquiry from their canopies to their ground layers. White oak (Quercus alba L.) was of higher importance in the more open old-growth canopy than the closed second-growth canopy which had more shagbark hickory (Carya ovata L.). The old-growth stand had higher floristic quality (mean Coefficient of Conservatism and adjusted Floristic Quality Index) and lower frequency of invasive species than the second-growth stand. The dominant white oak appear to have suppressed the hickories (Carya) for over a century on both sites. However, in the sapling and seedling layer, it appears the oaks and hickories are failing to recruit into the canopy on either site. The average age of the old-growth canopy is 67 years greater than that of the second-growth canopy, the majority of which seeded in after a heavy cut in the early 1940s. The second-growth site rapidly gained early successional species after the logging. The second-growth site could come to resemble the open oak dominated character of the old-growth site. However, this will require management with fire, thinning, and invasive species treatments. The old-growth, where sassafras (Sassafras albidum L.) is crowding the understory, will also require invasive species management, prescribed fire, and thinning if it is to remain the open oak-hickory woodland it is today.

No description available.