Academic literature on the topic 'Wyee Creek'

OPSOMMING In Antjie Krog se bundel mede-wete verskyn 'n aantal gedigte waarin die ek-spreker se soeke na 'n nuwe soort spiritualiteit verwoord word en waarin die implisiete versugting na die eenheid van alle dinge voorkom. Die doel van hierdie artikel is om 'n teoretiese konsep aan die hand te doen waarvolgens die spirituele aspekte in hierdie bundel bespreek kan word. Teorieë oor outobiografie as spirituele praktyk, veral in die digter se laatwerk, sowel as postsekularisme en ekopsigologie sal vir hierdie doel ingespan word. Daar sal hoofsaaklik eksemplaries te werk gegaan word deurdat enkele kerngedigte in die bundel ontleed word, te wete "moniaal", " 'n eland staan by 'n kuil", "ongelowig is nie die regte woord nie" en "kerssonnet". Daar word aangetoon op welke wyse Krog kategorieë of gehele wat in moderne tye hulle relevansie verloor het, poëties nuut verwoord deur te fokus op die verbeelding van 'n groter geheel waarin plante, diere en mense interverbonde is en interafhanklik van mekaar bestaan. Sodoende word die grense van die paradigma van egosentrisme waarin moderne mense verval het, opgehef en bestaande religieuse grense word deurbreek deurdat holisme op kreatiewe wyse as nuwe werklikheid daargestel word. Trefwoorde: Antjie Krog, mede-wete, outobiografie, laatwerk, postsekularisme, ekopsigologie, spiritualiteit, interverbondenheid, holisme ABSTRACT In Antjie Krog's collection of poetry, mede-wete (English translation, Synapse, by Karen Press)1there are a number of poems in which the author's search for a new kind of spirituality is articulated and in which the implicit longing for unity of all living things is suggested. Even before Socrates, philosophers speculated that wholes do indeed exist, but that their independently functioning parts are nothing but theoretical speculation. In modern physics, this concept is embodied in quantum field theory, which implies that everything that exists can be compared to waves at sea that cannot exist independently of the ocean. For the seeker of spiritual truth, the holistic path is a mystical path on which life reveals itself in its deeper meaning and "where our thoughts, feelings and actions are integrated by a clear intelligence and knowledge, and where a feeling of intimacy and participation with something greater than our normal selves occurs" (Ashraf 2012). In this manner the individual pursues so-called "higher knowledge". The purpose of this article is to suggest a theoretical paradigm on the basis of which the spiritual aspects in mede-wete can be discussed. I mainly rely on theories of autobiography as a spiritual practice, especially as an aspect of authors' "late work", post-secularism and ecopsychology when analysing a number of core poems, namely "moniaal", ("postulant"), "'n eland staan by 'n kuil" ("an eland stands at a pool"), "ongelowig is nie die regte woord nie" ("faithless is not the right word"), and "kerssonnet" ("christmas sonnet"). It can be argued that, in these poems, it becomes evident that rigid categories have lost their relevance in modern times. New categories have been imagined by the poet and phrased in poetic similes suggesting a larger whole in which plants, animals and people exist in interrelated and interdependent ways. In this way the boundaries of egocentrism by which modern people have been trapped are lifted, and existing religious boundaries are re-imagined through the creation of holism as a new reality - a reality that is greater than the sum of its individual elements; a liquid, ever-changing reality, adapted to the situation as it presents itself. The first section of the article focuses on spiritual autobiography and the individual's search for transcendent meaning as an aspect of identity construction. Spirituality involves, among other things, the feeling of interconnectedness with something greater than ourselves, which often includes a search for the meaning of the individual's life. As such, it is a universal human experience that can deeply affect human beings emotionally. Spiritual autobiography is often practised by writers who, towards the end of their lives, focus on the past in the light of universal human experiences in order to make sense of their own lives. Especially in autobiographies written in the later phase of an author's life, family and family relationships often play an important role - not only the role of the poet's ancestors and origins is investigated and reflected upon, but often children and even grandchildren form part of a reflection on the future and the legacy of the individual to posterity. It is precisely these poems that are examined in this article. Although mede-wete is clearly not intended as a spiritual autobiography, there is ample reason to consider several poems in this collection through the lens of theories on this particular genre, as there are such a large number of poems that correspond to the poet's (Antjie Krog's) biographical details. What is interesting is that three of the poems analysed directly follow on a poem about the poet's grandchildren or other toddlers. Therefore, I argue that there is a rhetorical connection between these "child poems" and the poems on spiritual reflection that directly follow them. It seems that "child poems" often give rise to reflection on transcendent experiences and to the need to explain these experiences. Several poems in mede-wete can be interpreted as confessions of faith. In the second section, I discuss the poem "kerssonnet" ("Christmas sonnet") from which it would appear that biblical metanarratives no longer provide modern people adhering to a secular value system with the hermeneutics of trust necessary for a firm belief in biblical truths. In its stead, the speaker, for example in a poem such as "ongelowig is nie die regte woord nie" ("faithless is not the right word"), suggests an alternative paradigm that does not imply a return to traditional religions, but rather a greater awareness of the continuing relevance of religion in secular societies. Such "post-secular" discourse is characterised by individual preferences for particular aspects of spirituality, implying that spirituality is still important, although it does not depend on the hegemony of mainstream discourse. In a post-secular world, new metaphors must be found to talk about God. In "ongelowig is nie die regte woord nie" ("faithless is not the right word") the following metaphor is significant: "we all drink like babies at a breast we feel / the nipple between our gums and say: it's / God (...)". By means of this metaphor, then, postmodern feminist discourse enters the poem - a discourse that refers to Julia Kristeva's theory of the mother as abject. Abjection here is the personification of the radical Other, the non-Self - or God. The poem "'n eland staan by 'n kuil" ("an eland stands at a pool"), discussed in the third section, depicts a mystical experience, an ecstatic moment in which the speaker comes into direct contact with the Holy One and feels herself, in a mystical way, being united with the universe. It is interesting to note that the eland is considered by San people to be a sacred animal, but that it is also the animal associated with rites of passage and initiation. My argument being that one can also read this poem as the creed of a newly initiated, someone who begins to walk a new spiritual path. The poem expresses the insight, which also underlies the whole volume of poetry, that all things created are interconnected. Keywords: Antjie Krog, synapse, autobiography, late work, post-secularism, ecopsychology, spirituality, interconnectedness, holism

ABSTRACT This work examined the role of micro-organisms in the biogeochemical cycling of selenium within the benthic ecosystem of Lake Macquarie, a coastal lake in New South Wales with a history of anthropogenic heavy metal contamination. Certain micro-organisms possess the ability to oxidise or reduce selenium (Fleming and Alexander, 1973; Doran and Alexander, 1977), and microbial volatilisation of selenium from contaminated sediments and soils utilising naturally-occurring microflora has been shown in overseas research (Thompson-Eagle and Frankenberger, 1992) to be a potentially effective remediation strategy. In examining the impact of micro-organisms upon the oxidation state of selenium in Lake Macquarie sediments, this work also investigated and characterised selenium (and heavy metal) concentrations, speciation and geochemical phase associations (an indicator of potential bioavailability) in the sediments. Seven distinct bacterial species indigenous to Lake Macquarie were identified in this work with the ability to reduce selenium as selenite to elemental selenium, and selenium as selenate to organic forms of selenium, including volatile methylated selenium compounds. Metabolic parameters calculated for these organisms compared favourably with those reported in the literature by other researchers. Mixed populations of sediment micro-organisms were also isolated and studied in this work for their selenite and selenate reduction abilities. Total reduction of added selenite at levels up to 100 mg/L was recorded for a number of the organisms studied in this work. A maximum specific uptake rate for selenite of 3040 mgSe(IV).(gcells)-1.(h)-1 for one isolate (Shewanella putrefaciens) was determined, exceeding rates reported in the literature by other authors. Use of the indigenous micro-organisms from Lake Macquarie for the bioremediation of selenium containing waste streams was also examined in this work and selenium reduction in an immobilised cell reactor was demonstrated with such organisms. Concentrations, speciation, sediment core profiles and geochemical phase associations for selenium were determined for sediment samples collected at a variety of sites throughout Lake Macquarie and from Wyee Creek, a selenium-impacted fluvial input to the lake. The maximum concentration of selenium obtained in this work for the lake proper was 4.04 mg/kg, considerably lower than values reported over a decade ago (Batley, 1987) but consistent with reported reductions of selenium input into the lake from the lead-zinc smelter. Selective extraction methodology (Tessier et al. and BCR methods) studied geochemical phase association of selenium in Lake Macquarie sediments and found up to 44% of selenium was in bioavailable forms. Of interest and environmental concern was levels of selenium found in sediments of Wyee Creek, which previously received overflows from the ash dam associated with the Vales Point Power Station. Sediment selenium levels of up to 300 mg/kg were determined for this creek. These were an order of magnitude or more greater than those recorded for the lake itself and are of concern as to the potential impact on benthic organisms and those animals, including humans, who consume them. While this work can only provide a 'snapshot' of conditions within Lake Macquarie at the time of the sampling events recorded herein, it does make several important contributions to the understanding of selenium biogeochemistry in Lake Macquarie. These include: presentation of the hypothesis that selenium levels in surficial sediments being deposited in the north of the lake have decreased in recent years as a result of selenium reduction measures undertaken by the lead-zinc smelter; determination that up to 44% of selenium in surficial sediments from the lake is associated with sediment phases in which selenium has the potential to become remobilized and hence possibly bioavailable; and documentation of selenium concentrations in Wyee Creek, identifying the area as having selenium concentrations an order of magnitude or more greater than the lake itself. Concerning the role played by microorganisms in the biogeochemical cycling of selenium in Lake Macquarie, this work has: identified individual isolated and mixed cultures of bacteria that can reduce selenium as selenite to lower oxidation states; identified individual isolated and mixed cultures of bacteria that can reduce selenium as selenate to lower oxidation states; identified volatile methylated selenium compounds in the headspace gases of microorganisms reducing selenate; determined Minimum Inhibitory Concentrations for selenate and selenite for organisms isolated from Lake Macquarie; identified casein hydrolysate as a preferred carbon source for selenium reducing microorganisms from Lake Macquarie; and demonstrated that bioremediation of selenium contaminated waste streams using indigenous organisms from Lake Macquarie is feasible on the laboratory scale. Further research areas suggested by this work include: additional investigations of elevated selenium levels in Wyee Creek sediments; determination of the role of microbes in in-situ selenium reduction; and optimisation of selenium biotreatment/bioremediation of selenium-containing waste streams and sediments. In summary, this work, in rejecting the null hypothesis that the oxidation states of selenium in sediments from Lake Macquarie, NSW, are independent of microbial activity and accepting the alternate hypothesis that these oxidation states are not independent of microbial activity, contributes to the understanding of the role of microorganisms in the biogeochemical cycling of selenium, having applicability to both the specific ecosystem of Lake Macquarie, NSW, and also to selenium cycling in the environment in general. In addition, this work has identified selenium contamination in Wyee Creek, one of the fluvial inputs to Lake Macquarie, which was previously been undocumented in the literature and which may pose significant potential risk to humans and the ecosystem due to sediment selenium levels one or more orders of magnitude higher than those recorded in the lake itself. Finally, this work has also identified a number of microorganisms indigenous to Lake Macquarie with the ability to reduce selenium from toxic, mobile forms to less toxic, immobile or volatile forms, and these organisms have been shown to have the potential for use in treatment of selenium contaminated waste streams and also in the bioremediation of selenium-contaminated sediments.

ABSTRACT This work examined the role of micro-organisms in the biogeochemical cycling of selenium within the benthic ecosystem of Lake Macquarie, a coastal lake in New South Wales with a history of anthropogenic heavy metal contamination. Certain micro-organisms possess the ability to oxidise or reduce selenium (Fleming and Alexander, 1973; Doran and Alexander, 1977), and microbial volatilisation of selenium from contaminated sediments and soils utilising naturally-occurring microflora has been shown in overseas research (Thompson-Eagle and Frankenberger, 1992) to be a potentially effective remediation strategy. In examining the impact of micro-organisms upon the oxidation state of selenium in Lake Macquarie sediments, this work also investigated and characterised selenium (and heavy metal) concentrations, speciation and geochemical phase associations (an indicator of potential bioavailability) in the sediments. Seven distinct bacterial species indigenous to Lake Macquarie were identified in this work with the ability to reduce selenium as selenite to elemental selenium, and selenium as selenate to organic forms of selenium, including volatile methylated selenium compounds. Metabolic parameters calculated for these organisms compared favourably with those reported in the literature by other researchers. Mixed populations of sediment micro-organisms were also isolated and studied in this work for their selenite and selenate reduction abilities. Total reduction of added selenite at levels up to 100 mg/L was recorded for a number of the organisms studied in this work. A maximum specific uptake rate for selenite of 3040 mgSe(IV).(gcells)-1.(h)-1 for one isolate (Shewanella putrefaciens) was determined, exceeding rates reported in the literature by other authors. Use of the indigenous micro-organisms from Lake Macquarie for the bioremediation of selenium containing waste streams was also examined in this work and selenium reduction in an immobilised cell reactor was demonstrated with such organisms. Concentrations, speciation, sediment core profiles and geochemical phase associations for selenium were determined for sediment samples collected at a variety of sites throughout Lake Macquarie and from Wyee Creek, a selenium-impacted fluvial input to the lake. The maximum concentration of selenium obtained in this work for the lake proper was 4.04 mg/kg, considerably lower than values reported over a decade ago (Batley, 1987) but consistent with reported reductions of selenium input into the lake from the lead-zinc smelter. Selective extraction methodology (Tessier et al. and BCR methods) studied geochemical phase association of selenium in Lake Macquarie sediments and found up to 44% of selenium was in bioavailable forms. Of interest and environmental concern was levels of selenium found in sediments of Wyee Creek, which previously received overflows from the ash dam associated with the Vales Point Power Station. Sediment selenium levels of up to 300 mg/kg were determined for this creek. These were an order of magnitude or more greater than those recorded for the lake itself and are of concern as to the potential impact on benthic organisms and those animals, including humans, who consume them. While this work can only provide a 'snapshot' of conditions within Lake Macquarie at the time of the sampling events recorded herein, it does make several important contributions to the understanding of selenium biogeochemistry in Lake Macquarie. These include: presentation of the hypothesis that selenium levels in surficial sediments being deposited in the north of the lake have decreased in recent years as a result of selenium reduction measures undertaken by the lead-zinc smelter; determination that up to 44% of selenium in surficial sediments from the lake is associated with sediment phases in which selenium has the potential to become remobilized and hence possibly bioavailable; and documentation of selenium concentrations in Wyee Creek, identifying the area as having selenium concentrations an order of magnitude or more greater than the lake itself. Concerning the role played by microorganisms in the biogeochemical cycling of selenium in Lake Macquarie, this work has: identified individual isolated and mixed cultures of bacteria that can reduce selenium as selenite to lower oxidation states; identified individual isolated and mixed cultures of bacteria that can reduce selenium as selenate to lower oxidation states; identified volatile methylated selenium compounds in the headspace gases of microorganisms reducing selenate; determined Minimum Inhibitory Concentrations for selenate and selenite for organisms isolated from Lake Macquarie; identified casein hydrolysate as a preferred carbon source for selenium reducing microorganisms from Lake Macquarie; and demonstrated that bioremediation of selenium contaminated waste streams using indigenous organisms from Lake Macquarie is feasible on the laboratory scale. Further research areas suggested by this work include: additional investigations of elevated selenium levels in Wyee Creek sediments; determination of the role of microbes in in-situ selenium reduction; and optimisation of selenium biotreatment/bioremediation of selenium-containing waste streams and sediments. In summary, this work, in rejecting the null hypothesis that the oxidation states of selenium in sediments from Lake Macquarie, NSW, are independent of microbial activity and accepting the alternate hypothesis that these oxidation states are not independent of microbial activity, contributes to the understanding of the role of microorganisms in the biogeochemical cycling of selenium, having applicability to both the specific ecosystem of Lake Macquarie, NSW, and also to selenium cycling in the environment in general. In addition, this work has identified selenium contamination in Wyee Creek, one of the fluvial inputs to Lake Macquarie, which was previously been undocumented in the literature and which may pose significant potential risk to humans and the ecosystem due to sediment selenium levels one or more orders of magnitude higher than those recorded in the lake itself. Finally, this work has also identified a number of microorganisms indigenous to Lake Macquarie with the ability to reduce selenium from toxic, mobile forms to less toxic, immobile or volatile forms, and these organisms have been shown to have the potential for use in treatment of selenium contaminated waste streams and also in the bioremediation of selenium-contaminated sediments.

The use of creep strength enhanced ferritic alloys such as Grade 91 in fossil power plants has become popular for high temperature piping applications. Since Grade 91 has higher stress allowables than Grade 22, a designer can specify thinner component wall thicknesses, resulting in lower through-wall thermal stresses during transient events and lower material and piping support costs. During the past two decades, Grade 91 has been used successfully in fossil power plants. However, this alloy has had some incidents of non-optimal weldment microstructure. In this case study, Brinell hardness tests of an ASME A182 Grade F91 (F91) wye block, including upstream and downstream F91 spools, revealed several readings of soft material, as low as 168HB. A study of creep rupture tests of degraded Grade 91 specimens revealed that the lower bound creep rupture curve of the degraded Grade 91 material is above the average creep rupture curve of Grade 22 material for the range of the specific piping operating stresses. Based on the empirical evidence that the average Grade 22 material creep rupture curve is conservative for the creep rupture of degraded Grade 91 material, a life consumption evaluation was performed for the degraded Grade 91 weldments using Grade 22 creep rupture properties. A life fraction analysis was performed considering the redistributed maximum principal stresses, based on simulation of piping displacements obtained from the hot and cold walkdowns. This study also considered the recent history of the specific piping system operating pressures and temperatures. This study also considered dissimilar metal welds, from ASME A182 Grade F91 (F91) to ASME A335 Grade P22 (P22) materials. It was determined that the Grades F91-to-F91 weldments had about 30% life consumption and the remaining lives were at least 7 years. The Grades F91-to-P22 weldments had less than 40% life consumption and the remaining lives were at least 15 years.