Estrogens produced by livestock can be released into soils when their manure is spread onto agricultural land. This is the first study to determine the sorption of a range of estrogens in a wide range of soils at the regional scale, including the sorption of the phytoestrogen equol which had never been previously studied. Sorption increased in the order of 17β-estradiol=estriol <estrone<equol in surface soils collected from 41 agricultural fields in Alberta and was significantly positively correlated with soil organic carbon content (SOC) for all estrogens. 17β-estradiol was further investigated and its mineralization in non-amended and manure-amended soils never exceeded 30% at 90 days, which suggest that even under optimum environmental conditions for mineralization, 17β-estradiol or its metabolites estrone and/or estriol appear to have a relatively long persistence in Alberta soils. Maximum 17β-estradiol mineralization was significantly positively correlated with sorption and hence increased in soils with greater SOC such as those used in this study with a long-term history of solid beef manure applications. Two ELISAs were developed using rabbit polyclonal antibodies for future field experiments and environmental monitoring. Of these, a developed 17β-estradiol+estrone+estriol ELISA could detect estriol in water from an edge of field experiment at concentrations as low as 1 ng mL-1.

Estrogens produced by livestock can be released into soils when their manure is spread onto agricultural land. This is the first study to determine the sorption of a range of estrogens in a wide range of soils at the regional scale, including the sorption of the phytoestrogen equol which had never been previously studied. Sorption increased in the order of 17β-estradiol=estriol <estrone<equol in surface soils collected from 41 agricultural fields in Alberta and was significantly positively correlated with soil organic carbon content (SOC) for all estrogens. 17β-estradiol was further investigated and its mineralization in non-amended and manure-amended soils never exceeded 30% at 90 days, which suggest that even under optimum environmental conditions for mineralization, 17β-estradiol or its metabolites estrone and/or estriol appear to have a relatively long persistence in Alberta soils. Maximum 17β-estradiol mineralization was significantly positively correlated with sorption and hence increased in soils with greater SOC such as those used in this study with a long-term history of solid beef manure applications. Two ELISAs were developed using rabbit polyclonal antibodies for future field experiments and environmental monitoring. Of these, a developed 17β-estradiol+estrone+estriol ELISA could detect estriol in water from an edge of field experiment at concentrations as low as 1 ng mL-1.

No description available.

No description available.

No description available.

Η παρούσα διατριβή εστιάζει στην μεταλλοφορία της περιοχής του Αγίου Γεωργίου στην Αντίπαρο στις Κυκλάδες, όπου κατά τα έτη 1953 έως 1954 πραγματοποιήθηκε εξώρυξη αργυρούχου γαληνίτη από την Γαλλική Εταιρία Λαυρίου. Η μεταλλοφορία βρίσκεται κυρίως υπό μορφή χαλαζιακών φλεβών, οι οποίες εκτός του αργυρούχου γαληνίτη φέρουν επίσης άλλα θειούχα μεταλλικά ορυκτά όπως ο χαλκοπυρίτης, ο σιδηροπυρίτης, ο βορνίτης και ο χαλκοσύνης. Το φλεβικό σύστημα τέμνει κυρίως μάρμαρα και σχιστολίθους. Τα συνοδά μη μεταλλικά ορυκτά αποτελούνται κυρίως από χαλαζία και δευτερευόντως από ασβεστίτη. Ο χαλαζίας διακρίνεται σε δύο γενεές, τον υψίθερμο γαλακτόχρωμο χαλαζία και τον χαμηλόθερμο διαυγή χαλαζία, από τους οποίους και οι δύο είναι μεταλλοφόροι. Στην ίδια περιοχή φιλοξενείται πρωτογενής μεταλλοφορία οξειδίων και υδροξειδίων του μαγγανίου. Ο σκοπός της διατριβής αυτής είναι να παραθέσει νέα, πρωτογενή δεδομένα όσον αφορά την ορυκτοχημεία των εναπομεινάντων θειούχων μεταλλικών ορυκτών που βρίσκονται τώρα στην περιοχή του Αγίου Γεωργίου και να προσδιορίσει τις φυσικοχημικές συνθήκες που συνέβαλαν στην απόθεση της μεταλλοφορίας. Επιπλέον ερευνά εάν ο λευκογρανίτης της Πάρου, ο οποίος απέχει λιγότερο από 10km από την μεταλλοφορία, δύναται να αποτελεί την πηγή των μεταλλοφόρων υδροθερμικών ρευστών. Για το λόγο αυτόν κατά την εκπόνηση της εργασίας υπαίθρου πραγματοποιήθηκε δειγματοληψία από την εναπομείνασα μεταλλοφορία του Αγίου Γεωργίου και το λευκογρανίτη της Πάρου. Επιπλέον συλλέχθηκαν τεκτονικά δεδομένα και έγινε συνοπτική καταγραφή και εκτίμηση των περιβαλλοντικών επιπτώσεων από τις παρελθούσες μεταλλευτικές δραστηριότητες στην περιοχή. Οι μέθοδοι που εφαρμόστηκαν για την επίτευξη της έρευνας ήταν η ανάλυση των θειούχων μεταλλικών ορυκτών με ηλεκτρονικό μικροαναλυτή, ανάλυση XRF και ICP-MS για κύρια στοιχεία, ιχνοστοιχεία και σπάνιες γαίες στον λευκογρανίτη της Πάρου, πετρογραφική μελέτη λεπτών τομών από το γρανίτη και στιλπνών τομών από τη μεταλλοφορία. Επίσης εφαρμόστηκε μικροθερμομετρία στα ρευστά εγκλείσματα εντός του συνοδού υδροθερμικού χαλαζία για τον προσδιορισμό των θερμοκρασιών απόθεσης και της αλατότητας των μεταλλοφόρων ρευστών. Στα ρευστά εγκλείσματα εφαρμόστηκε επίσης η μέθοδος της φασματοσκοπίας Raman. Πραγματοποιήθηκαν αναλύσεις σταθερών ισοτόπων O18 και Si30 από τον υδροθερμικό χαλαζία για τον προσδιορισμό της προέλευσης των υδροθερμικών ρευστών. Τα τεκτονικά δεδομένα υποδηλώνουν πως τα ορυχεία του Αγίου Γεωργίου βρίσκονται πάνω σε μία καμπύλωση των πετρωμάτων της περιοχής. Βάσει πετροχημικών και πετρογραφικών δεδομένων η λευκογρανιτική διείσδυση στην Πάρο φέρει τυπικά χαρακτηριστικά ενός subsolvus λευκογρανίτη κεκορεσμένου σε νερό, ο οποίος διείσδυσε σε περιβάλλον ηφαιστειακού τόξου υπό καθεστώς συμπίεσης, σε θερμοκρασίες από ~758οC έως ~676οC και σε βάθη από ~15km έως ~3km. Γρανίτες τέτοιου είδους συνδέονται συχνά με υδροθερμικά μεταλλοφόρα συστήματα, όπως κατάγραφεται από τη διεθνή βιβλιογραφία. Οι ισοτοπικές τιμές δ18ΟH2O εντός του μεταλλοφόρου υδροθερμικού ρευστού της περιοχής του Αγίου Γεωργίου κυμαίνονται μεταξύ +5,4‰ και +11,5‰, με μέσον όρο +8,3‰, το οποίο αποτελεί ένδειξη ανάμειξης ρευστών μαγματικής προέλευσης, με ισοτοπικές τιμές από +5‰ έως +10‰, μεταμορφικών ρευστών τα οποία έχουν τιμές από +10,71‰ έως +14,5‰ για τους σχιστολίθους της ενότητας των κυανοσχιστολίθων και από +19,7‰ έως +20,5‰ για τα μάρμαρα της ίδιας ενότητας, μετεωρικών υδάτων τα οποία είχαν ένα εύρος από -5‰ έως -2‰ κατά το Μειόκαινο και θαλλασίων υδάτων που έχουν εύρος από +1,5‰ έως +2‰. Οι θερμοκρασίες κατά τις οποίες έλαβε χώρα το υδροθερμικό μεταλλοφόρο επεισόδιο κυμαίνονται μεταξύ ~400οC και ~140οC. Σε διάγραμμα Th προς την αλατότητα εμφανίζεται συνεχής μείξη μεταξύ μαγματικών ρευστών και ενός παράγοντα χαμηλής αλατότητας, πιθανόν μετεωρικών ρευστών. Στο ίδιο διάγραμμα εμφανίζεται αναβρασμός του υδροθερμικού ρευστού και φραγή του φλεβικού συστήματος μεταξύ 280οC και 250οC. Το φλεβικό σύστημα άνοιξε εκ νέου σε θερμοκρασία χαμηλότερη των 250οC πιθανότατα λόγω βρασμού του υδροθερμικού ρευστού. Τα δεδομένα από τη φασματοσκοπία Raman υποδεικνύουν την παρουσία κατιόντων Ca2+, Si2+, Al3+, Ti, Li+, B3+ και Cu2+, καθώς και των ανιόντων SO42- και CO32- εντός των ρευστών εγκλεισμάτων. Κυρίαρχα ιόντα εντός του διαλύματος αποτελούν τα Ca2+, Na+, K+, Mn2+ και Si2+. Η παρουσία των ιόντων Li+ και B3+ είναι ενδεικτική της συμμετοχής των λευκογρανιτών στο μεταλλοφόρο υδροθερμικό ρευστό. Τα ιόντα Cu2+ και SO42-, δείχνουν την παρουσία των απαραίτητων για την απόθεση της μεταλλοφορίας ιόντων και τα ιόντα Ca2+ και CO32- δείχνουν την αλληλεπίδραση του υδροθερμικού ρευστού με τα μάρμαρα του Αγίου Γεωργίου. Βάσει των log(Na+/K+) προς log(K+/Ca2+), γίνεται εμφανές πως ορισμένα εκ των δειγμάτων φέρουν πανομοιότυπα τιμές δείγματα από γεωθερμικά πεδία στα οποία συμμετέχουν και τα μετεωρικά ρευστά. Οι τιμές αυτές πέφτουν στην ίδια κατηγορία με σύγχρονα γεωθερμικά ρευστά τα οποία πιστεύεται πως αντιπροσωπεύουν ρευστά μαγματικής προέλευσης τα οποία αναμείχθηκαν με ρευστά μετεωρικής προέλευσης. Αξίζει δε να σημειωθεί από τις αναλύσεις με ηλεκτρονικό μικροαναλυτή της μεταλλοφορίας η ύπαρξη άφθονου βαρύτη (BaSO4), που υποδηλώνει ότι μέρος της μεταλλοφορίας εθαλάσσευε. / The present thesis focuses on the mineralization in the area of St. George (Agios Georgios) in the island of Antiparos in Cyclades where in the years 1953 to 1954 argentiferous galena was mined-out by the French Corporation of Lavrion. The mineralization was in the form mainly of quartz veins and also calcite which except of argentiferous galena consisted also of other sulfides such as chalcopyrite, pyrite, bornite and chalcocite cutting mainly marbles and schists. The non-metalliferous hydrothermal minerals consist of calcite but mainly of quartz of two generations; a high temperature milky quartz and a low temperature clear quartz, both of which are mineralized. In the same area there is an occurrence of primary mineralization of manganese oxides and hydroxides. The purpose of this thesis is to provide ore mineral chemistry data of the sulphide mineralization which remains presently in situ and define the main physicochemical conditions for ore deposition. Furthermore, the purpose is to investigate if the Paros leucogranite (<10km away), could be the source of the mineralizing fluids. For this reason, during field work, sampling of the mineralization and the Paros leucogranite, collection of structural data and registering and evaluation of the environmental impact the previous mining activities had on the St. George terrain was accomplished. The methods we have used to effectuate our research, was electron microprobe analyses of the sulfide ore minerals, XRF and ICP-MS analyses of major, trace and REE of the Paros leucogranite, examination of petrographic thin sections of the granite and polished sections of the ore mineralogy. Microthermometric measurements of fluid inclusions in the accompanying hydrothermal quartz were performed to define the temperatures of deposition and salinities of the ore fluids. Raman spectroscopy data of fluid inclusions were collected. O18 along with Si30 isotope analytical data of the hydrothermal quartz were obtained to decipher the origin of the hydrothermal fluids. Our structural data can only indicate that the mines are situated on an open flexure which facilitated in the axial area the concentration of the ore fluids and their circulation via the formation of diaclases. Our chemical and petrographic data indicate that the Paros intrusion has the mineralogy and geochemistry of a typical subsolvus volatile-saturated leucogranite emplaced in a volcanic arc tectonic environment under compression at temperatures from 758oC to 676oC and at a depth of 15km to 3km, as indicated by amphibole geobarometry. Such granites are reported in the literature to be often associated with mineralizing hydrothermal ore systems. The O18 isotopes of the quartz veins in St. George have δ18O values ranging from +6.5‰ to +12.6‰, with an average of +9.4‰ and an 18O signature of the mineralizing fluid of +5.4‰ to +11.5, with an average of +8,3‰ which is almost identical with a magmatic Η2Ο isotope composition from +5‰ to +10‰. Further evidence indicates that metamorphic, meteoric and sea-water have participated, if to a lesser degree, in the Agios Georgios mineralizing fluid. Temperatures of the hydrothermal episode range from ~400οC to ~140oC. On a Th-Salinity diagram continuous mixing is indicated between a magmatic and a low temperature and salinity component. In the same diagram effervescence of the hydrothermal fluid is indicated. A closure of veins has occured between 290oC to 250oC. The system was re-opened at approximately 250oC probably due to boiling of the ore fluid. Raman data have indicated the presence of Ca2+, Si2+, Al3+, Ti, Li+, B3+ and Cu2+ cations and SO42- and CO32- anions in the fluid inclusions, the most dominant ions in the solution being Ca2+, Na+, K+, Mn2+ and Si2+. The presence of Li+ and B3+ ions betray the participations of the leucogranite in the ore fluid. The Cu2+ and SO42- the presence of mineralizing ions and finally the Ca2+ and CO32- ions the interaction of the hydrothermal fluids with the St. George marble. From the log(Na+/K+) versus log(K+/Ca2+) ratios, it is apparent that some of the samples have identical values with the ones related to meteoric participating waters. The presence of barite (BaSO4) identified by electron microprobe within some of the ore samples is indicative that part of the deposit was under sea level.

Land application of poultry litter has been successfully practiced for centuries to maintain and improve soil fertility, although over application may promote loss of nutrients through runoff or leaching. To decrease the potential for adverse environmental impacts of N and P in groundwater, a new approach developed in this research was to use a composted mixture of poultry litter (PL) and yard waste (YW) as a soil amendment for corn (Zea mays L.) production. Objectives of this research were to evaluate effects of pre-compost C:N substrate ratios for poultry litter-yard waste compost (PYC) on the availability of soil P, to determine the P response of corn plants to inorganic P, PL and PYC application, and to study relationships between P availability and both inorganic P and PYC application. Langmuir isotherms were used in this research to select soils with relatively high P fixation capacities. Phosphorus sorption maximum for soils evaluated were as follows: 304 and 449 micrograms of P per gram for A horizon Coastal Plain soils (Series: Kempsville and Myatt, respectively); 487 micrograms of P per gram for an A horizon Ridge and Valley soil (Series: Frederick); 918 and 603 micrograms of P per gram for A horizon Piedmont soils (Series: Elioak and Vance, respectively); 1099 microgram of P per gram for mine tailings (Series: Emporia located in the Coastal Plain); and 1524 microgram of P per gram for A and upper mixed horizon soil (Series: Starr from Piedmont region). Based on intermediate to high P sorption maxima, soil from the Vance and Starr series and mine tailing from Emporia series were selected for greenhouse research to evaluate P availability of PYC . Treatments applied to the soil in the greenhouse and field studies consisted of various levels of P as Ca(H₂PO₄)₂.H₂O, PL and PYC from 15:1, 20:1, and 25:1 C:N ratio substrates. Each P source increased dry weight of corn plants grown in the greenhouse by alleviation of P deficiency. Phosphorus uptake from PYC and PL application was either equal to or higher than P uptake from an equal level of P application as Ca(H₂PO₄)₂.H₂O. Application of 87.2 kg of P per ha increased corn grain yields in a field experiment on Vance sandy loam from 6340 kg per ha on the control to a range of 10,170 to 11,350 kg ha for PYC digested from the three C:N ratio substrates. The yields on PYC treatments were attributed to a combination of factors including slow mineralization of P with less fixation during the growing season. The low P fixing capacity results from the blockage of H₂PO₄⁻ sorption by competition of negative charge from organic material and from the displacement of H₂PO₄⁻ in soil solution by OH⁻ from application of the alkaline composts. It would be desirable from the standpoint of more PL utilization to prepare composts from low substrate ratio substrates. Hence, in this research composts were prepared from 15:1, 20:1, and 25:1 C:N substrates, which consisted of PL and YW. The composting process was complete after only four months for the PYC from the 20:1 and 25:1 C:N ratio substrates. Yard waste compost without PL may require somewhere between two to three years for complete composting as opposed to four months with PL addition. The composting was incomplete in four months (presence of undigested leaves and NH₃) for the PYC from the 15:1 C:N ratio substrate. The latter compost resembled poultry manure rather than a high quality compost after the 4-month composting period. / Ph. D.

No description available.

A reconstrução de defeitos ósseos é um problema que afeta milhões de pessoas, que a medicina tenta resolver. Uma alternativa para a solução deste problema tem sido o desenvolvimento de biomateriais que atuem no processo de reparação óssea. O colágeno é um polímero de origem natural capaz de promover cicatrização e regeneração óssea e juntamente com a hidroxiapatita são os principais componentes encontrados no tecido ósseo. Vários trabalhos têm sido reportados com matrizes mineralizadas de colágeno tipo I em diferentes formas como em géis, membranas e esponjas, mas a mineralização in vitro de matrizes acelulares obtidas de tecidos biológicos sem a perda da estrutura colagênica não tem sido descrito. Este trabalho teve como objetivo a mineralização in vitro e a caracterização de matrizes de colágeno aniônico obtidas de pele porcina, pericárdio bovino e serosa porcina. Os tecidos foram tratados em temperatura ambiente com solução alcalina por períodos variáveis de 0 à 96h e mineralizados pelo processo de imersão alternada. Os materiais obtidos foram caracterizados pela avaliação preliminar da citotoxicidade in vitro, termogravimetria (TG/DTG), calorimetria exploratória diferencial (DSC), microscopia eletrônica de varredura (MEV), dispersão de raios X (EDS), difração de raios X (DRX) e absorção no infravermelho (FT-IR). Não foi observada citotoxicidade em nenhuma das matrizes avaliadas, contudo foi necessário um pré-tratamento nas matrizes de pele porcina para remoção de gordura. Os resultados de DSC mostraram a integridade da matriz colagênica após o tratamento alcalino. O aumento no tempo desse tratamento diminui a temperatura de desnaturação sendo observado um efeito maior nas matrizes de pele porcina seguidas por pericárdio bovino e serosa porcina. A mineralização induz a um aumento na temperatura de desnaturação em todos os casos. As curvas TG apresentaram perdas de massa relacionadas à água presente no material, decomposição da proteína e carbonização do material orgânico e um resíduo após 750 °C que foi associado ao material inorgânico presente na forma de hidroxiapatita, sendo as matrizes de serosa porcina as de maior teor de mineralização. As matrizes mineralizadas tendem a um aumento na estabilidade térmica do colágeno quando comparadas com as matrizes hidrolisadas. Os espectros FT-IR mostraram a presença de íons fosfatos e a interação de íons cálcio com o colágeno. As relações Ca/P obtidas por EDS foram aquelas esperadas em comparação com o valor teórico para hidroxiapatita (HA) e resultados de DRX confirmaram a obtenção de HA amorfa como principal produto de mineralização. Pelas fotomicrografias obtidas por MEV pôde-se observar que as fibras de colágeno tornam-se mais desestruturadas quando há um aumento no tempo de hidrolise e que a deposição de sais ocorreu de forma heterogênea, disposta em aglomerados esféricos no formato de agulhas por toda a superfície e interior, exceto para matrizes derivadas de pele porcina que não são mineralizadas internamente devido a sua espessura. Os resultados obtidos demonstraram que é possível a mineralização in vitro de matrizes de colágeno tipo I obtidas de diferentes tecidos biológicos em diferentes tempos de hidrólise, produzindo um material com potencial de uso para regeneração óssea. / The reconstruction of osseous defects is still a problem that affects millions of people and medicine tries to solve it. One alternative to solve these problems has been the development of biomaterials that can be used as inductors in the osseous repair process. Collagen is a natural polymer able to promote healing and bone regeneration, and among hydroxyapatite (HA) is the main component found in bone tissue. Several mineralized collagen scaffolds are described in literature, in the form of gel, membranes and films, however, in vitro mineralization of acellular matrices, obtained from biological tissues without the loss of collagenic structure, has not been reported. The objective of this work was the mineralization and characterization of anionic collagen matrices obtained from porcine skin, bovine pericardium and porcine serosa. Biological tissues were treated at room temperature for 0-96h in alkaline solution and mineralized by alternate soaking method. Materials were characterized by preliminary assay of in vitro cytotoxicity, differential scanning calorimetry (DSC), termogravimetric analysis (TG/DTG), scanning electronic microscopy (SEM), energy dispersive x-ray analysis (EDS), x-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). No cytotoxicity was observed in any of the evaluated matrices; however, a pre-treatment of porcine skin matrices, for fat removal, was necessary. DSC results showed the integrity of collagen matrices after alkaline treatment. Denaturation temperature is dependent of time of alkaline treatment, and this effect is greater for porcine skin matrix, followed by bovine pericardium and porcine serosa. TG/DTG curves showed weight losses associated with release of water, degradation of protein structure and combustion of residual organic components. Residues were obtained at 750°C and associated to hydroxyapatite, being porcine serosa matrix the most mineralized. All mineralized matrices showed an increase in collagen thermal stability when compared to hydrolyzed matrices. FTIR spectra showed the presence of phosphate ions and the interaction of calcium ions with collagen. Ca/P ratios obtained by EDS were as expected when compared with literature values for HA, and RDX results confirmed amorphous HA as the main mineralization product. MEV analysis showed that collagen fibers were more affected for longer hydrolysis times, and that salt deposition was heterogeneous, with crystals grouped in spherical agglomerates in a needle-like shape throughout surface and inner, except for porcine skin derived matrices that were not internally mineralized due their width. Obtained results demonstrated that in vitro mineralization of type I collagen matrices, using different sources of biological tissues and hydrolysis time was possible, producing a material with potential to be used in bone regeneration.

Iron is the most abundant trace metal in the brain and is essential for many biological processes, such as neurotransmitter synthesis and myelin formation. This thesis investigates small, multifocal hypointensities that are apparent on T2*- weighted (T2*w) MRI in the basal ganglia, where presumably most iron enters the brain via the blood-brain-barrier along the penetrating arteries. These basal ganglia T2*w hypointensities are believed to arise from iron-rich microvascular mineral deposits, which are frequently found in community-dwelling elderly subjects and are associated with age-related cognitive decline. This thesis documents the characteristic spatial distribution and morphology of basal ganglia T2*w hypointensities of 98 community-dwelling, elderly subjects in their seventies, as well as their imaging signatures on T1-weighted (T1w) and T2- weighted (T2w) MRI. A fully automated, novel method is introduced for the segmentation of basal ganglia T2*w hypointensities, which was developed to reduce the high intra- and inter-rater variability associated with current semi-automated segmentation methods and to facilitate the segmentation of these features in other single- and multi-centre studies. This thesis also presents a multi parametric quantitative MRI relaxometry methodology for conventional clinical MRI scanners that was developed and validated to improve the characterisation of brain iron. Lastly, this thesis describes the application of the developed methods in the segmentation of basal ganglia T2*w hypointensities of 243 community-dwelling participants of the Austrian Stroke Prevention Study Family (ASPS-Fam) and their analysis on R2* (=1/T2*) relaxation rate and Larmor frequency shift maps. This work confirms that basal ganglia T2*w hypointensities, especially in the globus pallidus, are potentially MRI markers of microvascular mineralization. Furthermore, the ASPS-Fam results show that basal ganglia mineral deposits mainly consist of paramagnetic particles, which presumably arise from an imbalance in the brain iron homeostasis. Hence, basal ganglia T2*w hypointensities are possibly an indicator of age-related microvascular dysfunction with iron accumulation, which might help to explain the variability of cognitive decline in normal ageing.