A variety of extractants were used to fractionate the trace metals Cd, Cu, Mn, Ni, Pb, and Zn in contaminated urban soils. The metals were mostly held in soil solid phases but not in soluble and exchangeable forms. Except for Mn, extractability of metals by selective chemicals was mainly a function of the contamination level. The speciation of these elements in water, 0.01 M CaCl2, and pH-adjusted water extra was calculated using the chemical equilibrium model MINEQL+. The free ions of Cd, Ni, and Zn were the predominant species in most of the water and 0.01 M CaCl2 extracts while PbCO30 was the main form of Pb. Organically complexed Cu accounted for over of the total dissolved Cu. The solubility of trace metals increased as solution pH was decreased. Metals Cd, Ni, Pb and Zn combined with Cl- at low pH (<5). Organically complexed Cu was shifted to Cu2+ when pH was decreased. / Except for Mn, the activities of the other metals in water, 0.01 M CaCl 2 extracts, and pH-adjusted water extracts were undersaturated with respect to established minerals in soils. MnHPO4 seems to be controlling the solubility of Mn in these extracts.

The work in this thesis demonstrates whether resins are better than conventional soil extractants at predicting plant metal concentrations, and whether low-cost soil treatments can effectively reduce metal content and concentrations in lettuce leaves. / Researchers have shown that ion exchange resins can simulate root metal uptake behaviour by acting as ion sinks. Chemical extractants on the other hand, generally do not behave in this manner. Thus, we would expect resins (in either bead or membrane form) to predict plant metal concentrations better than conventional extractants. For the first study, a procedure using anion exchange resin membranes (AEM) treated with either EDTA or DTPA chelators was chosen, since previous studies showed this method to be effective at predicting plant metal uptake, and practical for routine laboratory use. In addition, several conventional extractants were selected for comparison. / For the second part of the thesis, a study was undertaken to test the effectiveness of various food processing byproducts to stabilize metal contaminants in soils, and compare the results with those of a Na-based aluminosilicate (zeolite). (Abstract shortened by UMI.)

Trace metal contamination of the air-soil-tree system was examined in southern Quebec, where acid deposition and tree dieback have been recorded in high elevation forests. Mn pollution was emphasized due to its large emission from gasoline combustion in Canada. Airborne Cu, Mn, V, and Zn showed higher concentrations than those reported for other remote locations. Significant fluctuation in Mn concentrations during the winter-spring season was explored by air mass back trajectory analysis. The study suggested that high Mn concentrations resulted from the atmospheric long-range transport from Canadian industrialized and metropolitan regions. Metal concentrations in podzolic topsoils were generally higher than their world-wide average values. Concentrations of trace metals in balsam fir (Abies balsamea (L.) Mill) needles were below their suggested potential phytotoxic levels, except for Mn, which also increased with elevation. The scanning of needles with micro-PIXE showed no significant correlation between metal accumulation and epistomatal distribution on foliar surfaces. / Pathways of trace metals deposited in the soil-tree system were elucidated through application of $ sp{54}$Mn and $ sp{65}$Zn on shoot, bark, and soil surfaces in growth-chamber experiments with balsam fir seedlings. Uptake and accumulation by seedlings 70 days after application on the shoot surface was about 25-30% of the remaining activities for $ sp{54}$Mn and $ sp{65}$Zn. Less than 1% of absorbed isotopes was translocated from the bark surface to other plant organs, whereas more than 50% of the radioisotopes absorbed at the shoot moved to the rest of the seedling. Acidic wetness facilitated the metal absorption through tree surfaces. Downward movement of the radioisotopes in podzolic soils was documented, and accumulation in seedlings by root uptake was 5% of the remaining activity for $ sp{54}$Mn and 3% for $ sp{65}$Zn 70 days after application. No appreciable elemental migration from internal tissues to epicuticular wax layers was found, and the leaching ratio was below 0.5 and 1.0% for $ sp{54}$Mn and $ sp{65}$Zn, respectively. This study helps to understand the links between atmospheric deposition and the elevated levels of Mn in trees, and potential effects of acid deposition on the bioaccumulation of toxic metal pollutants in high elevation forests in southern Quebec.

One of the first concerns for forensic anthropologists in dealing with skeletal remains in the Australian context is the determination of whether the remains are of anthropological, historical or archaeological interest. If fewer than 75 years have elapsed since death, remains are classified as anthropological and of forensic interest. However, an accurate and reliable method for estimating time since death (TSD) from human skeletal remains has thus far eluded forensic anthropologists. This study investigates the application in an Australian context of a novel approach proposed by Swift (2001) to dating skeletal remains from their contained levels of radioisotopes 210Po, 238U and 226Ra and trace elements. Radionuclide activity concentrations were determined using alpha and gamma spectrometry. Trace element concentrations were measured on three separate occasions using inductively coupled plasma mass spectrometry (ICP-MS). Discriminant analysis of the combination of activity concentration values for 210Po, 238U and 226Ra indicated the possibility of separation of bones derived from individuals who had died in the three eras of interest. Additionally, variations in the concentration levels of specific trace elements and certain inter-element relationships between elements also showed significant correlations with TSD. The study could not be exhaustive as access to human skeletal material was limited and additionally, the archaeological material had a different origin and post-death history to material from the more recent past. However, trend lines for inter-relationships between specific metals and for radionuclides indicated that all material fitted the same generally projected trends and as such, inferences with respect to variations of trace elements and radionuclides could be made with confidence. Bone radionuclide activity and calcium concentrations were all significantly higher in bones from the archaeological era than those from more recent eras, while trace lead concentrations contained in samples from the more recent historical era were significantly higher than those from other eras. Barium, lanthanum, rubidium, strontium, cerium and neodymium concentrations were all significantly correlated with one another and with radionuclide activity concentrations. Differences were found between the patterns of radionuclide activity and trace element concentrations between the skull and femur. The results of this study lend support to suggestions that multivariate analysis of trace element concentrations and radionuclide activity levels could aid in the estimation of time since death from skeletal remains in Australia. Although this study made use of only a limited amount of material, results clearly indicated the need to take into account variations arising from lifetime activities, diagenesis and bone type in applying the techniques to estimations of time since death. It highlights the need for a large-scale study using bone of known ages that systematically examines these influences on the estimation of time since death.

Mounted ill. / Offprint of the author's journal article in pocket / Includes bibliographies / xiii, 248 leaves, [50] leaves of plates, [3] folded leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1985

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 5 uppsatser.

Thesis (M.Sc.)(Hons) -- University of Western Sydney, 2005. / "A thesis presented to the University of Western Sydney in fulfilment of the requirements for the degree of Master of Science (Honours) Physics" Bibliography: leaves 101-108.

Thesis (MNutr (Human Nutrition))--Stellenbosch University, 2008. / Background Critical illness is associated with increased production of reactive oxygen species and oxidative stress, and low levels of most micronutrients with resultant diminished endogenous antioxidant defences. Micronutrient supplementation is thought to be beneficial to the critically ill patient by ameliorating oxidative stress and by improving clinical outcome. Objectives This systematic review assessed the effects of micronutrient supplementation on adults recovering from critical illness. Primary outcomes included clinical endpoints [mortality, infectious complications, length of intensive care unit and hospital stay (LICU and LOS)]. Secondary outcomes included descriptions of practice issues, micronutrient status, morbidity, course of the acute phase response and oxidative stress. Search strategy An electronic bibliographic database search was carried out, bibliographies of retrieved articles were reviewed and personal files searched to obtain additional citations. Databases were searched from inception until 29 February 2008. Selection criteria Randomized controlled trials (RCTs) of micronutrient supplementation (by any route) in adult critically ill patients, given in addition to their routine care, were included. Data collection and analysis Two authors independently extracted data and assessed trial quality. For the primary outcomes the random-effects model was used to estimate overall relative risk / mean difference and effect size due to the presence of study heterogeneity. Selected exploratory analyses were undertaken. Differences at the level of p<0.05 was considered to be statistically significant. The secondary outcomes were sparse and variably recorded such that this data was not formally aggregated. Main results Fifteen RCTs involving 1714 participants and 18 RCTs involving 1849 participants were included for the primary and secondary objectives respectively. The quality of the RCTs, as reported, was disappointing, particularly for allocation concealment. Fourteen trials (n=1468) of micronutrient supplementation showed a statistically significant reduction in overall mortality [relative risk (RR) 0.78, 95% confidence interval (CI) 0.67-0.90, I2=0%, p=0.0009]. An asymmetrical funnel plot necessitates caution when directly interpreting these results. Six RCTs (n=1194) indicated a statistically significant reduction in 28 day mortality (RR 0.75, 95% CI 0.63-0.88, I2=0%, p=0.0006) (symmetrical funnel plot). Micronutrient supplementation in this systematic review was not associated with a reduction in infectious complications, LICU or LOS. In sub-group analyses, single nutrients were associated with borderline statistical significance (RR 0.82, 95% CI 0.66-1.01, I2=0%, p=0.06) in terms of mortality, whist a sensitivity analysis of combined micronutrients indicated a significant reduction in mortality (RR 0.69, 95% CI 0.54-0.90, I2=2%, p= 0.006). This review did not find clear evidence that parenteral is superior to enteral administration in terms of clinical outcomes. The secondary outcomes confirmed that timing, duration and dosing are key factors to ensure optimal clinical benefit. Conclusion This review does suggest potential benefit of micronutrient supplementation in critically ill adults for some clinical outcomes (especially mortality), but also highlights that caution is warranted as nutrient interactions and risk of toxicity are not clearly defined in critical illness. More large multi-centre randomized trials are necessary to assess the effects of different types and doses of micronutrient supplementation in selected groups of patients with different types of critical illness.

Orientador: Gustavo Henrique de Almeida Teixeira / Coorientador: Vivian da Silva Santos / Banca: José Dalton Cruz Pessoa / Banca: José Fernando Durigan / Resumo: O palmiteiro juçara (Euterpe edulis Mart.) é endêmico do bioma conhecido por Mata Atlântica, sendo seus frutos semelhantes ao do açaizeiro (Euterpe oleracea Mart.), porém mais ricos em antocianinas e em alguns elementos químicos, o que os tornam um importante produto para a alimentação das comunidades tradicionais. Todavia, durante o processamento, os frutos passam por diferentes etapas para a extração de sua polpa, o que podem afetar a bioacessibilidade dos micronutrientes. Objetivos: O objetivo geral deste trabalho foi verificar a bioacessibilidade de micronutrientes no mesocarpo dos frutos e polpa de juçara e, por objetivos específicos: i. verificar o efeito das diferentes etapas do processamento na bioacessibilidade dos micronutrientes presentes no mesocarpo dos frutos e polpa de juçara ii. determinar a bioacessibilidade in vitro dos micronutrientes pelo método da digestão gastrointestinal (IVG) seguida de análise por espectrômetro de emissão óptica com plasma indutivamente acoplado (ICP-OES). Métodos: Em cada etapa do processamento foi colhido o mesocarpo dos frutos e/ou polpa para a determinação da bioacessibilidade dos micronutrientes utilizando o método da digestão gastrointestial in vitro (IVG). Os elementos cálcio (Ca), magnésio (Mg), ferro (Fe), manganês (Mn), cobre (Cu) e zinco (Zn) foram determinados por ICP-OES. O experimento foi conduzido segundo um delineamento em blocos casualizado (DBC), onde os blocos foram constituídos pelas origens (Uba... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Juçara palm tree (Euterpe edulis Mart.) is endemic from a biome know as Atlantic Forest, and its fruit are similar to açaí (Euterpe oleracea Mart.), but richer in anthocyanin and chemical elements, which make them a important food produce for the local population. However, during its processing, the fruit are subjected to different unit operation to extract their pulp and it can affect the chemical elements biaccessibility. Objectives: The general object of this study was to verify the chemical elements bioaccessibility in fruit and juçara pulp and, the specific objectives were: i. verify if the different unit operations affect the chemical elements bioaccessibility, and ii. determine the in vitro chemical elements bioacessibiity using the in vitro gastrointestinal method (IVG) followed by ICP-OES determination. Methods: For each unit operation during juçara processing fruit and/or pulp were collected to determine the chemical elements bioacessibility using the in vitro gastrointestinal method (IVG). It was determined the chemical elements Ca, Mg, Fe, Mn, Cu and Zn using Inductively coupled plasma atomic emission spectroscopy (ICP-AES). The experiment was conducted according to randomized complete blocks design (CBD), where the blocks were constituted by the origens (Ubatuba I, Ubatuba II, Jaboticabal I, Jaboticabal II and Américo Brasiliense) with four treatments (i. fresh harvested fruits, ii. fruits which were washed, iii. fruits after softened in water, iv. processed pulp). Results: It was not possible to determine the bioaccessibility of Ca and Zn. The chemical elements Mg, Mn, Cu, and Fe bioaccessibility reduced during processing. Conclusion: Juçara fruit processing affected the content and bioaccessibility of the chemical elements, and it was observed a sharp increment in the content of macro and microelements... (Complete abstract click electronic access below) / Mestre