18 research outputs found
Toxic Cyanobacteria: Education, Lake Protection
No full textWashington State Department of Health received a Centennial Clean Water Fund grant in 1994 from Washington State Department of Ecology to investigate cyanobacteria blooms in western Washington. Objectives of the grant, entitled "Toxic Cyanobacteria: Education/Lake Protection," were to: (1) educate the public about potential health concerns and train citizens to recognize and report algal blooms in lakes, (2) investigate potential inhibitors of cyanobacteria, and (3) observe blooms in two western Washington lakes. During this grant, Pacific Lutheran University (PLU) tested field samples for toxicity and conducted research on cyanobacteria inhibitors. Seattle University (SU) conducted limnological field work in Lake Steilacoom and American Lake, Pierce County. A review of scientific literature on toxic cyanobacteria included the following topics: toxin-producing cyanobacteria, cyanobacterial toxins (neurotoxins, hepatotoxins, other toxins, detection), occurrence of freshwater cyanobacterial toxicity, impacts on human health, impacts on aquatic life (zooplankton, fish), and conditions leading to toxic bloom formation (nutrients, light and temperature, toxin production and growth cycle, zooplankton, other factors). Also in the literature review was information on control of toxic cyanobacteria blooms (lake management, copper sulfate, calcium hydroxide, aluminum sulfate, other treatments, and drinking water treatment). Education of lake groups and citizens was conducted during the grant. A large part of educating the public and public agencies about toxic cyanobacteria blooms occurred through response to requests for information, primarily from government agencies but also from citizens and businesses associated with aquatic activities. The above interactions were summarized in the final report. In addition, a brochure on toxic cyanobacteria was produced and distributed, a training manual on identification of potentially toxic cyanobacteria was distributed, and public meetings and local workshops on toxic cyanobacterial blooms were conducted. Local health district personnel were trained at three regional workshops in western Washington. Four public workshops were held for various groups, such as Phantom Lake Association (King County), Kitsap County, Long Lake Steering Committee (Thurston County), and the 1996 joint annual meeting of the Western Plant Management Society and North American Lake Management Society. Presentations on cyanobacteria toxicity were given at other conferences and meetings throughout the grant period.
A total of 115 lake samples were tested for toxicity during the 30-month grant. Samples were collected from 20 different lakes in eight western Washington counties: Pierce (5), King (6), Thurston (3), Kitsap (2), Snohomish (1), Skagit (1), Mason (1), and Clark (1). An additional four lakes outside western Washington were tested: Wenas Lake, Yakima County, East Lake, California, and Big Creek Reservoir and Devil's Lake, Oregon. A database summarizing lakes sampled and results of toxicity tests was completed for the final report. Toxic blooms were confirmed by mouse bioassay in five of the twenty-one Washington lakes sampled. Lake Steilacoom, Spanaway Lake, Waughop Lake (Pierce County), and Wenas Lake (Yakima County) contained toxic Microcystis aeruginosa, while American Lake (Pierce County) contained toxic Anabaena flos-aquae. Microcystin-LR was the variant that occurred regularly in the microcystin-containing blooms. No other toxin-producing cyanobacteria was detected during this study, although several genera known to produce toxins were found. Most cyanobacterial blooms occurred during the late summer and early fall, while a small number occurred during the winter months in water temperatures as low as 5-7°C. Of primary public health concern were toxic cyanobacterial blooms in lakes which are used as a source of drinking water. Lake Young, a drinking water reservoir in King County, was monitored for cyanobacteria on a regular basis during the grant. Summit Lake, Thurston County, a source of drinking water to nearby residents, had a cyanobacterial bloom that tested negative for toxicity in July 1995. Residents of Lake Wenas, Yakima County, became ill after their drinking water became toxic in September 1995; the bloom showed microcystin-LR and -RR. In Oregon, a toxic Microcystis bloom in Big Creek Reservoir, the drinking water supply for Newport, led to notification of residents and to further tests for microcystins in tapwater throughout the bloom.
Three reports of illness after swimming in a cyanobacterial bloom were documented. Numerous youths became ill after swimming in a Gloeotrichia bloom in Mason Lake, Mason County, during Labor Day weekend 1995. Reports of human illness, dead trout, and a dead kingfisher were received after a bloom in Goss Lake, Island County. Fort Lewis Fish and Wildlife reported a bloom, a fish kill, and a sick child at Little American Lake, Pierce County, 1995. In each of the above cases, the cyanobacterial bloom had dissipated or decayed before samples were taken for toxicity tests. Several other reports of fish kills associated with blooms were received during the grant. In efforts to isolate cyanobacteria inhibitors, PLU isolated a water-soluble material from the green seaweeds Ulva and Monostroma. The isolate exhibited killing activity (cell lysis) against a toxic strain of Anabaenaflos-aquae. Real-time videomicroscopy showed that the substance caused cell wall perforation, followed by outward extrusion of the cell contents, and death within 1-2 hours. Bioactivity-directed fractionation was used to partially purify the lytic agent from both seaweeds. The agent appeared to be a small glycoprotein (MW=1,000-4,000) and was stable for several months at room temperature. SU investigated two lakes with histories of toxic blooms, American Lake and Steilacoom Lake (Pierce County) in order to: (1) identify and evaluate possible relationships between environmental factors and development of toxic blooms, (2) determine the relationship between the presence and abundance of potentially toxic species and toxin production, and (3) incorporate information gained into approaches for managing toxic cyanobacterial blooms. The two lakes were monitored during 1994 and 1995 for toxicity and for physical, chemical, and biological indicators.
No samples collected in American Lake during winter 1994-1995 elicited a toxic response in mouse bioassays, although low levels of microcystin were detected in selected samples by ELISA. One sample collected near Veterans Hospital along the northern shoreline was identified as toxic in February 1996. Since this sample was the only toxic sample observed, it was not possible to identify relationships between toxicity and environmental conditions in American Lake. A prolonged toxic bloom of Microcystis aeruginosa occurred in Steilacoom Lake during summer 1994. Total microcystin concentrations at the deep-water station ranged from 209 to 1286 ug/g bloom material. During most of summer 1995, cyanobacteria were not abundant and samples tested for toxicity did not give a toxic response. Only one sample in October 1995 was toxic by mouse bioassay.
In Lake Steilacoom, cyanobacterial blooms were associated with decreased water column light intensity and transparency as measured by Secchi depth, and stable water column conditions as estimated by relative thermal resistance to mixing (RTRM). Although cause and effect relationships cannot be discerned from field observations, there was a significant linear relationship between increasing percent cyanobacteria and decreasing Secchi depth measurements (r = 0.69, p < 0.001), a negative exponential relationship between the concentration of cyanobacteria and Secchi depth (r = 0.82, p < 0.0001), and a negative exponential relationship between Microcystis concentration and Secchi depth (r = 0.76, p < 0.0005). RTRM was significantly higher during summer 1994 (p < 0.05), indicating more stable conditions due to a greater density gradient and more resistance to mixing. Stable and turbid conditions during summer 1994 possibly gave buoyancy-regulating cyanobacteria like Microcystis an advantage at obtaining optimum light conditions for photosynthesis. The same type of cyanobacterial bloom did not occur in summer 1995, possibly due to greater water column transparency and lower stability.
Increased water column transparency can be partially explained by trophic level interactions between planktivorous fish, zooplankton, and phytoplankton. Zooplankton abundance dramatically increased between 1994 and 1995 (means of 18.4 and 62.9/L, respectively) concurrent with a large decrease in the number of young hatchery fish planted in the lake and upstream creeks. The number of fingerlings and fry planted in Steilacoom Lake and upstream creeks in 1995 (201,150) was approximately half of the number planted in 1994 (395,050).
Phytoplankton losses due to zooplankton grazing were estimated to be greater during 1995 than 1994, with losses due to grazing potentially contributing approximately 80 percent of the total loss. The large zooplankton population in 1995 exerted a large grazing pressure on phytoplankton and kept the phytoplankton biomass low through September. With a less stable water column and high transparency due to zooplankton grazing, low light conditions (which would have. favored cyanobacteria) did not develop until October 1995.
Other factors were associated with cyanobacterial dominance in 1994. Mean surface water temperature in 1994 was higher than in 1995 (22.6°C and 20.6°C, respectively). Temperature exceeded 20°C in both years, but temperature in 1994 was greater than 22°C more often than in 1995.
Mean surface pH was significantly higher in Lake Steilacoom during the toxic bloom in 1994 (p < 0.05), with pH values consistently close to 10 from mid-July through September. Greater phytoplankton growth earlier in the summer increased pH levels earlier in 1994. Cyanobacteria increase pH during photosynthesis and, in turn, are favored by the high pH conditions that they create. Also, the large biomass of macrophytes present during summer 1994 (both submerged and floating) removed C02 from solution and contributed to the raised pH. Macrophytes were scarce the second summer. Mean summer total phosphorus (TP) concentrations were also different between the years (p < 0.05), with a significant positive relationship between cyanobacteria concentration and surface TP concentration (r = 0.66, p < 0.0005). Additionally, mean summer total nitrogen (TN) was significantly higher during the toxic bloom in 1994 than in 1995 (p < 0.05). Low No3-N concentrations in Lake Steilacoom in 1994 may partly explain the success of Microcystis that year; the only peak in cyanobacteria biovolumn that occurred during 1995 was after No3-N concentrations dropped below 20 ug/L.
Microcystin concentration in Lake Steilacoom was not related to Microcystis in the water column. Different limnological conditions probably affect growth of Microcystis and microcystin production. Microcystin concentration increased with increasing soluble reactive phosphorus (SRP) between 1 and 10 ug/L; toxin production by Microcystis may have been limited by SRP.
Management approaches to prevent occurrences of a toxic bloom are the same as those that would be used to address any nuisance phytoplankton blooms. The most important factor to be managed is nutrient loading to the lake. Management methods include dredging, dilution, treatment or diversion of point sources, and watershed best management practices. Sources of P and N should be identified, and if TP inputs to the lake can be decreased, cyanobacterial blooms will be less likely.
Factors that may reduce phytoplankton in Lake Steilacoom are increased dilution and flushing of the lake and a large zooplankton population. Increased flushing rate decreases inflow nutrient concentrations if the inflow concentration is less than the lake concentration. Increased flushing may also increase the phytoplanktonloss rate. Zooplankton populations can be significantly affected by planktivorous fish grazing; increased planktivorous fish mortality may protect zooplankton which then graze phytoplankton. Treatment with algicides such as copper sulfate effectively removes phytoplankton cells from the water column. However, treatment by chemicals causes phytoplankton cells to lyse and release all intracellular compounds, including the toxin. It would be unwise to cause toxin release without concern and caution for public health; toxins may remain in the water for up to 40 days. Avoiding cell lysis and toxin release is imperative when treating drinking water reservoirs that have cyanobacterial blooms. Alternative chemical treatment methods would be alum, lime, or another chemical coagulant.
Lakes with toxic bloom potential should be monitored for the presence of large blooms of cyanobacteria or scums on the surface, especially along the shoreline. Lake residents should be educated to watch for scum formation and alert their public health agency when a large bloom is occurring so that the bloom can be tested for toxicity; toxicity analysis should be conducted using a quantitative technique such as HPLC or ELISA. If a surface scum is observed, lake residents should restrict domestic animal and human use of waters. Lakes or reservoirs serving as drinking water sources should be periodically monitored for cyanobacteria presence and abundance, and, if a potential toxin-producing species is found, a concentrated sample should be analyzed for toxicity. Toxin-producing cyanobacteria may pose a danger to human health due to the potential tumor-promoting characteristics of their toxins
Gospel and culture - accommodation or tension? : an enquiry into the priorities of the Gospel in the light of Jamaica's historico-cultural experience vis-à-vis Western Christian civilization
No full textIn this thesis we enquire into the essence and mission of
Christianity in the light of the Jamaican historico-cultural experience.
Chapter one is devoted to a partial investigation into the nature of
Western Christianity vis-a-vis Western Civilization - the modern dilemma,
its historical beginnings and development, its response to philosophical
ideas and other cultural positions, Church-State relations, its divisions,
and its social attitude.
We next identify the major elements in the Jamaican experience as
revealed in the impact of the Spanish conquest on the original Arawak
population, the enslavement of African Peoples, and the post-slavery
repercussions vis-a-vis Western Christianity.
In order better to understand the New Testament Gospel we locate its
origin in the Old Testament examining its relationship with the Law and
Temple, Priesthood and Prophets, observing its social implications, and we
follow it en route to the New Testament.
In chapter four we engage in a brief examination of the Hellenistic
cultural environment including the Jewish Diaspora, in order to have a
grasp of the initial interaction between Gospel and Culture.
Our concern in chapter five is to recover the essence of Jesus’
proclamation of the Gospel as witnessed to in the Synoptics. From this
go on to examine its transmission to the wider Hellenistic milieu,
concentrating on the Pauline and Johannine presentations.
Finally it is argued that the Gospel in its transmission across
cultures should be proclaimed, as far as possible, without cultural
accretions; that the prevailing categories and symbols understood within
the indigenous Jamaican culture be appreciated and, where possible,
appropriated for purposes of communication; and, fundamentally, that in
all circumstances the Church should faithfully guarantee a synchronization
between its message and action, and Jesus’ Gospel of the Kingdom of God,
described in terms of Good News to the Poor
Preclinical evaluation of lime juice as a topical microbicide candidate
No full textBackground: The continued growth of the global HIV epidemic highlights the urgent need to develop novel prevention strategies to reduce HIV transmission. The development of topical microbicides is likely to take a number of years before such a product would be widely available.
This has resulted in a call for the rapid introduction of simpler vaginal intervention strategies in the interim period. One suggested practice would be vaginal douching with natural products including lime or lemon juice. Here we present a comprehensive preclinical evaluation of lime juice (LiJ) as a potential intervention strategy against HIV.
Results: Pre-treatment of HIV with LiJ demonstrated direct virucidal activity, with 10% juice inactivating the virus within 5 minutes. However, this activity was significantly reduced in the presence of seminal plasma, where inactivation required maintaining a 1:1 mixture of neat LiJ and seminal plasma for more than 5 minutes. Additionally, LiJ demonstrated both time and dosedependent
toxicity towards cervicovaginal epithelium, where exposure to 50% juice caused 75–90% toxicity within 5 minutes increasing to 95% by 30 minutes. Cervicovaginal epithelial cell monolayers were more susceptible to the effects of LiJ with 8.8% juice causing 50% toxicity after 5
minutes. Reconstructed stratified cervicovaginal epithelium appeared more resilient to LiJ toxicity with 30 minutes exposure to 50% LiJ having little effect on viability. However viability was reduced by 75% and 90% following 60 and 120 minutes exposure. Furthermore, repeat application (several times daily) of 25% LiJ caused 80–90% reduction in viability.
Conclusion: These data demonstrate that the virucidal activity of LiJ is severely compromised in the presence of seminal plasma. Potentially, to be effective against HIV in vivo, women would need to apply a volume of neat LiJ equal to that of an ejaculate, and maintain this ratio vaginally for 5–30 minutes after ejaculation. Data presented here suggest that this would have significant adverse
effects on the genital mucosa. These data raise serious questions about the plausibility and safety of such a prevention approach
AVMA council on biologic and therapeutic agents'; report on cat and dog vaccines
No full textID: 4527; LR: 20031114; JID: 7503067; 0 (Vaccines); CIN: J Am Vet Med Assoc. 2003 Apr 15;222(8):1072-3; author reply 1073. PMID: 12710767; CIN: J Am Vet Med Assoc. 2003 Jan 15;222(2):149-50; author reply 150-1. PMID: 12555974; CIN: J Am Vet Med Assoc. 2003 Feb 1;222(3):283. PMID: 12564583; CIN: J Am Vet Med Assoc. 2003 Mar 15;222(6):714, 716. PMID: 12675291; ppublishSource type: Electronic(1
Evoking the Possibility of Presence:Textual and Ideological Effects of Linguistic Negation in Written Discourse
No full textThis thesis explores the textual and ideological effects of linguistic negation in written texts. It argues that when language users process negation, understanding its use in context is as much about the possibility of presence as it is about the actuality of absence. This gives rise to a variety of effects in texts from contributing to the construction of fictional characters to potentially influencing readers’/hearers’ view of the world they inhabit. This thesis brings together research on the theoretical aspects of how negation works to present a new approach to linguistic negation in written discourse. It also demonstrates how this approach can be applied in the analysis of the conceptual practice of negating. The approach presented is made up of three main elements; negation is presuppositional, is realised through a wide variety of linguistic forms beyond the morphosyntactic core forms (not, no, never, none, un-, in-, and so on) and includes semantic and pragmatically implied forms. These two elements combine to give rise to implied meaning in context. Having outlined this approach to negation, it is then applied in the analysis of literary and non-literary texts to explain the textual and ideological effects that arise from its use
Six Pillars of Social Policy: The State of Pensions and Health Care in Canada
No full textWilliam B.P. Robson, a co-author with David Slater of a series of papers on pension issues, has written an ambitious survey of the state of Canadian economic policy in the areas of pensions and health care. He argues that it is appropriate to tackle both issues in the same paper because they are both major spending programs strongly related to the life cycle of Canadians, and face challenges arising from the aging of the population. Robson notes that the pension debate uses the metaphor of three pillars to describe a comprehensive pension system: a safety net to guard against destitution in old age; a mandatory employment-related system to provide basic replacement income; and a voluntary system supported by provisions that reduce the double-taxation of saving. The main elements of public policy related to pensions in Canada cover these pillars. He recognizes that all three of the pillars cannot be directly applied to health care, but he argues that the three-pillar metaphor is still a fruitful perspective because it facilitates constructive responses to the pressures confronting Canada’s health system and illuminates interactions between the pension and health systems. Hence his title “six pillars of social policy”. Based on his examination of Canada’s pension and health-care systems, Robson makes a number of recommendations. First, he advocates more prefunding in both the pension and health areas to cover the future cost of the aging baby-boom cohort. Second, he recommends a gradual increase in the normal age of eligibility for pension benefits. Third, he recommends the creation of a second pillar, a mandatory contribution scheme in the health area as a way to avoid the development of a means-tested system that would exacerbate the disincentives to work and save. Fourth, he puts forward the idea of a new type of saving vehicle that provides tax-relief on distributions rather than on contributions so that Canadians can avoid the high marginal effective tax rates associated with means-tested programs.Health, Health Care, Health-care, Healthcare, Canada, Pensions, CPP, Retirement, Mandatory Contribution, Aging, Ageing
The critical use of narrative and literature in gerontology
No full textIt is now widely accepted that "age" and "ageing" are cultural concepts that are open to question. The thinking encouraged by critical gerontology has been crucially important in provoking questions about the complexities of later life, age and ageing. Similarly, the interrogation of stories of age and ageing via narrative approaches and as found in literature are increasingly recognised as an important source of knowledge for mining the intricacies of later life. There are close links between the interests of critical gerontologists and those who engage in narrative and literary gerontology. However, the potential that critical gerontology has for illuminating and probing these stories of age has often been neglected. The central argument of this article is that narrative and literary approaches to age and ageing when allied to perspectives from critical gerontology can furnish scholars with important perspectives for interpreting and re-configuring "age". The focus is upon how a genuinely dialogic relationship between critical gerontology and narrative and literary gerontology can be forged. In this way, the full potential of these stories of ageing; their epistemological status for enriching theoretical work on ageing, might be better exploited
A peer mediation program piloted in the fourth grade at Black Earth Elementary School
No full textPlan BDespite concerns about increasing violence by educational officials, parents, and community members, most school programs do not provide students specific educational experiences that facilitate adequate personal and social development. Some schools, nationally, have addressed this need by offering educational programs teaching conflict resolution skills through peer mediation. The purpose of this study was to determine whether a peer mediation program piloted in a fourth grade population would encourage students to use conflict resolution skills to resolve disputes peacefully. The model used is called the Peers in Education Addressing Conflict Effectively (PEACE) Program, whose goal is to teach appropriate conflict resolution skills, and decrease hostility in the school environment.
Fifteen mediators, selected by their peers, were taught the PEACE program skills of conflict resolution. These skills include communication, reflective listening, identifying feelings and problem solving. The mediators were trained by the author and another staff member who had been trained in the PEACE Program.
The time frame of the study was from January 1999 to January 2000. Information was gathered through questionnaires given to peer mediators, a questionnaire answered by the fourth grade population and fourth grade teachers, anecdotal records and observations from participating teachers and the school principal. Results of the study did not show a reduction in antisocial behavior or reduced violence in the school. The findings did suggest that the mediators learned the conflict resolution skills, but because of the time schedule, opportunities to practice and use them were limited. Students and teachers did demonstrate positive interest in the program; students wanted to become trained mediators and teachers and administrators supported the concept of peaceful problem-solving. Data collected from the study will be used to evaluate the effectiveness of the program, identifying strengths and weaknesses for future program implementations
Dressing the part : costuming of lesbian identities in contemporary film and television
No full textThis thesis examines lesbian costuming and dress in contemporary British and American
film and television, offering analyses of sartorial constructions of gay female identities in
modern media. It uses close textual analysis and interviews with producers and consumers
to examine the production, texts, and reception of selected representations, outlining current
social rituals of lesbian style. Interviews were held with Cynthia Summers, Lesley
Abernethy, Niamh Morrison, Catherine Adair, Janie Bryant, Tina Scorzafava and Mary Claire
Hannan about their designs. Spectators answered questions and responded to photographs
and a transcript. The thesis argues that the modern-day designer of lesbian costuming is
subject to a contradictory triangle of demands, encompassing the need for costume to
support character, resistance to stereotypes, and the recognition and perceived positive
politics of identifiable lesbianism. Chapters covering Lip Service and The L Word;
Desperate Housewives, Deadwood, and Mad Men, and Gillery’s Little Secret and The Kids
Are All Right examine differing results of these pressures. The thesis argues that while
anxiety over ‘butch’ stereotypes and heteronormative mainstream demands for assimilation
play a part in the overwhelming ‘femininity’ of many examples, an increase in lesbian
visibility has also paradoxically instigated a shift away from specificity in media
representations through dress because lesbianism is no longer seen as a ‘story’. It suggests
that lesbian authorship and using real-life lesbian styles as costume inspiration may offer a
way out of the stereotype vs. ‘authentic’ imagery impasse without erasing recognisably
lesbian iconography. Finally, the thesis concludes that the production, text and reception of
contemporary lesbian images at times comprises a complete circuit of communication, with
production decisions and everyday practices of lesbian dress both echoing and informing
one another
The price approach to financial integration: Decomposing European money market interest rate differentials
No full textFinancial Policy;Financial Markets;EMS;Interest Rate
