Acid Mine Drainage (AMD) is an environmental problem that eventually occurs in sulfide rich mine sites. In Turkey most of the metal mines are associated with sulphide minerals and are potential AMD generators. The purpose of this PhD thesis is to practice universally accepted tools for the prediction of AMD potential for a new metallic mine development. This study involves evaluation of geological data, geochemistry, mineralogy, and acid-base accounting (static tests) data, obtained from the Erzincan-ili&ccedil / &Ccedil / &ouml / pler Gold Prospect case. The mineralization in &Ccedil / &ouml / pler is in sulfide and oxide types. The oxide is a supergene alteration and porphyry-copper type gold mineralization is classified as an intermediate sulfidation. The major lithologies observed in the study area are the regionally un-correlated meta-sedimentary lithologies, Munzur Limestone, and the &Ccedil / &ouml / pler Granitoid.Thirty-eight representative samples were tested for AMD prediction purposes. Sixteen more were included to the sampling scheme for site characterization. Both acid producing and neutralizing lithologies are present in the mine site. Similarly it was revealed that the sulphate sulfur content of the samples were insignificant that any determined total sulfur amount can be directly considered as the factor for AMD production. Geochemical data revealed arsenic enrichments up to 10000 ppm in the study area. Therefore, during the operational stage, in addition to the planning to avoid or minimize AMD, it is necessary to take precautions against arsenic mobilization during the design of the AMD neutralization scheme. Both Kinetic studies and the heavy metal mobilization related to AMD are kept out of the scope of this investigation. Similarly, management and abatement stages of AMD are excluded.

The literature review shows that student alternative conceptions or misconceptions are important for teaching and learning. Causes of such student difficulties may include the counter-intuitive nature of some chemistry concepts or to instruction itself. However, over 30 years research into student conceptual difficulties has had little impact on teaching and learning chemistry. In this study, a critical analysis and synthesis of published research into student conceptions in acid-base chemistry was carried out in the naturalist nomothetic paradigm using a constructivist framework. Historical models which were included were an operational macroscopic model and the theoretical Arrhenius and Brønsted models. Firstly, a comprehensive search strategy with defined inclusion/exclusion criteria identified 42 suitable reports which were mostly peer-reviewed. The identified research was not limited to Anglophone countries although Africa and South America were underrepresented and research among secondary students predominated. Then a critique of the research showed it was of variable quality and often poorly reported. An outcome was a set of guidelines for research into student conceptions. The variable quality and reporting of research then also necessitated a four-level framework to reflect the stability of descriptions of student difficulties. A new method for synthesis of descriptions of student conceptual difficulties was developed which entailed mapping qualitative data on the difficulties, which had been extracted from research publications, to propositional knowledge statements derived in this study. This was an iterative process which simultaneously honed descriptions of difficulties and illuminated propositional knowledge implicated in them. The second major outcome was synthesized descriptions of 10 student difficulties with acid-base species, 26 difficulties with acid-base properties and 17 difficulties concerning terminology and symbolism particular to acid-base chemistry. Some conceptions were also found to have been mis-reported as ‘misconceptions’. The difficulties could be broadly due to student conceptions concerning acid-base models, or students not relating empirical observations to theoretical models or their poor understanding of underlying chemical principles. Some difficulties were found to have been over-researched, while further work was needed to clarify the nature some difficulties with conceptions of bases, acid-base reactions, and symbolism used in acid-base chemistry. The third major outcome from the synthesis was 218 propositional knowledge statements which were shown to be suitable for teaching high-school students, avoided hybrid historical models and were acceptable to expert chemists. These propositional statements were integrated as a set of 11 concept maps. The maps showed the hierarchy and interconnectedness of concepts as well as the propositional links which had been implicated in the difficulties. Furthermore the concept maps indicated critical concepts where teaching in each topic should focus as well as cross-linked concepts that can be used to integrate different aspects of the topic. Accordingly they contribute to PCK in the acidbase topic as they represent the fine-grained yet well integrated conceptual knowledge characteristic of a teacher with highly developed PCK. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.

Goldfish undergo an adaptive morphological change in their gills involving the reversible growth and loss of a mass of cells (interlamellar cell mass, ILCM) in between the lamellae depending on oxygen demand, which can be altered by the environment or metabolic demands of the individual. The ILCM contributes to decreased passive Na+ efflux across the gill. Active uptake is maintained by the re-distribution of the ionocytes expressing Na+-uptake relevant genes (NHEs and H+-ATPase) to the outer edge of the ILCM where they can establish contact with the external environment and/or lamellar epithelium. This adaptation is thought to be partly responsible for the extreme anoxia tolerance demonstrated by goldfish, which they experience on a seasonal basis living in a pond environment. Hypoxia and hypercapnia are frequently encountered in such freshwater environments and as such, the effect of the ILCM on the capacity for acid-base regulation was evaluated. Differences in the time course of acid excretion to the environment without effect on systemic pH regulation were likely the result of the ILCM.

Glycerol and fructose are molecules that are readily available in substantial quantities fromthe biomass. In this work dehydration routes for valorization of these compounds wereinvestigated. Therefore, zirconia and titania based catalysts, and calcium phosphate materialswere prepared and evaluated in the glycerol dehydration in gas phase. Niobia-ceria mixedoxides and mesoporous Nb2O5-MeO2 (M = Ce, Zr, Ti) mixed oxides were prepared andtested in fructose dehydration reaction in aqueous phase. The surface acid-base properties ofthe studied catalysts were correlated to their catalytic performance.

This study was conducted to explore the effectiveness of analogy-enhanced instruction accompanied with concept maps over traditionally designed chemistry introduction on understanding of acid-base concept and attitude toward chemistry as a school subject. 81 8th grade students from two classes of a chemistry course taught by the same teacher in Nuh Eskiyapan Primary School in Ankara in 2003-2004 fall semesters were enrolled in the study. There were two groups of students. During the treatment, students in the control group were instructed only with traditionally designed instruction. Students in the experimental group studied with the analogy-enhanced instruction accompanied with concept maps through teacher lecture. Both groups were administered Acid-Base Chemistry Achievement Test and Attitude Scale toward Chemistry as a School Subject as pre-tests and post-tests. Logical Thinking Ability Test was given to both groups at the beginning of the study to determine students&rsquo / logical thinking ability levels. Research data were analyzed by using (SPSS 12.0) ANCOVA and t-test. As a result of the research, it was obviously seen that analogy-enhanced instruction accompanied with concept maps caused a significantly better acquisition of scientific conception related to acid-base and produced significantly higher positive attitudes toward chemistry as a school subject than the traditionally designed chemistry instruction.

[Truncated abstract] The influence of environmental conditions and properties of pyritic shale in the mining waste from Mt. Whaleback in Western Australia, in particular the inclusions and encapsulation of pyrite on the oxidation of pyritic shale and its subsequent acid mine drainage, was studied by employing an isothermal batch reactor system and QEMSCAN technique. The experimental technique was validated by comparing the experimental results obtained in this study with the literature data. It was found that the presence of water significantly accelerates the rate of shale oxidation. Weathering of the shale samples was found to influence the O2 consumption rate. It was also found that shale properties have a major effect on the oxidation rate and thereby affect the acid generation. Static test methods (Sobek and Lawrence) were employed to test the Neutralisation Potential (NP) of more than 100 actual and composite samples including pyritic shale samples, rock samples, mineral samples, various pyrite-mineral, pyrite-shale, and pseudo-shale blends. The influence of sample properties (bulk elemental composition, and mineralogy), test technique (Sobek and Lawrence) and associated variables (acid strength and volume) on the acid neutralisation potential of the samples was studied. It was found that the Sobek method produced consistently higher NP results under comparable acid conditions to those obtained with the Lawrence method. The theoretical NP values of individual minerals were calculated based on the mineral composition combined with the acid neutralising equations and ideal chemical formula. ... To experimentally model the major mineral phases, 11 minerals were used to produce pyrite-mineral blends and pseudo-shales, whose compositions mimic those of the actual shales studied. Mineral blends were employed to evaluate and contrast their individual acid generation or neutralisation behaviour with binary and higher order interactions. Blends of pyrite with some selected shales were also employed in this study. It was found that interactions can occur between the multiple mineral components which can enhance the rate of acid generation beyond that of the individual behaviour. It was found that the products from the pre-oxidation of shales, the properties and morphology of a sample such as the surface area, encapsulation, the mineralogy and pH all play a significant role in the acid generation and neutralisation rates. However, the absolute rate of acid generation appears to be most sensitive to the components such as Fe3+, which contribute to its reaction mechanisms. This investigation has provided a scientific insight into the acid generation and neutralisation behaviour of pyritic shale in relation to its mineralogy. It was found that the relative instantaneous rates of acid generation and consumption for individual minerals can be significantly different to that of their total potentials for acid generation and neutralisation. The significantly different behaviour of the actual and pseudo shales suggests that at low pH, there may be other mechanisms underlying the net capacity and rates of shales to generate or consume acid than bulk mineralogy. These findings have significant implications to the mining industry operating in reactive grounds.

In this work, there was observed the influence of feeding an anionic salt on acid-base value in the urine (ABV) and on a level of the calcium in the urine in high yielding dairy cows. This mineral ingredient was tested for two feeding rates: winter - conserved, summer - pasture and was fed in a rate 450 g per a cow and a day. In the winter experimental period there were found no changes in AVB and the effect of Rindavit MF Sauer wasn´t expressed. In the sum-mer experimental period the influence of Rindavit MF Sauer on acid-base balance was fully expressed although the high potassium level in the feed rate. We found statistically significant differences between control and experimental group at observing levels of calcium and the effect of the anionic salt was shown. There was found no case of the milk fever in experimental group cows dduring the whole test. By contrast, there were recorded two cases of the milk fever in the control group cows. At feeding the anionic salt, we didn't find any negative effect on the acid - base balance and the health of the cows.

Em Medicina Veterinária, os avanços em Neonatologia são escassos quando comparados aos da Medicina Humana. Dentre as possíveis causas para esta situação atual destacam-se as particularidades fisiológicas deste período. Os objetivos do presente estudo foram: estabelecer os valores normais de algumas variáveis laboratoriais de neonatos nascidos de parto eutócico, identificar eventuais alterações metabólicas maternas e dos neonatos nascidos em diferentes condições obstétricas, verificar os efeitos da administração de ocitocina sob variáveis neonatais e maternas e mensurar os níveis de cortisol materno e neonatal como forma de estudar as diferentes situações de estresse no momento do parto. Vinte e nove fêmeas caninas foram alocadas em 3 grupos, de acordo com o tipo de parto: eutocia (grupo 1), distocia corrigida por manobras obstétricas ou cesariana (grupo 2) e indução de contrações uterinas com ocitocina (grupo 3). Cinqüenta e um neonatos foram avaliados por meio do sistema Apgar e temperatura corpórea ao nascimento, 5 minutos e 1 hora após o nascimento, bem como por avaliação hemogasométrica, dosagem de cortisol e glicemia ao nascimento e após 1 hora. A avaliação materna constituiu no controle da pressão arterial, monitorização cardíaca, glicemia e dosagem de cortisol em momentos pontuais no pré, intra e pós-parto. Os neonatos dos distintos grupos apresentaram acidose mista associada à hipóxia ao nascimento, com maior comprometimento metabólico nos filhotes do grupo 3. Após 1 hora, recuperaram-se do componente respiratório, mantendo apenas o quadro de acidose metabólica por maior comprometimento da hipóxia. A avaliação neonatal pelo escore Apgar demonstrou que filhotes do grupo 2 nascem em maior depressão que neonatos dos grupos 1 e 3, porém todos apresentam adequada recuperação após 1 hora. Nas parturientes, a administração de ocitocina favoreceu a elevação da pressão arterial para níveis normais durante o trabalho de parto, bem como o aumento da glicemia. Neonatos nascidos por manobra obstétrica ou cesariana apresentaram maior concentração de cortisol plasmático ao nascimento, em comparação aos grupos 1 e 3. Contudo, todos os neonatos apresentaram redução significativa dos níveis de cortisol após 1 hora do nascimento. Por outro lado, foi possível verificar maior concentração sérica deste hormônio após o término do parto nas fêmeas submetidas à infusão de ocitocina. Em conclusão, a administração de ocitocina é responsável por maiores alterações metabólicas em neonatos; na parturiente, a administração de ocitocina promove alterações na pressão arterial, glicemia e aumento da liberação de cortisol; a manobra obstétrica ou cesariana promove maior estresse neonatal ao nascimento. / Studies accomplishing canine neonatology are scarce in Veterinary Medicine comparing to Human Neonatology due to the particularity of this refered period. The aims of the present study were to establish standard laboratorial values of the canine neonate, identify metabolic changes of bitches and neonates born under different obstetric conditionsl, verify the consequences of dystocia treated medically by oxytocin administration on maternal and neonatal variables and to measure maternal and neonatal cortisol levels on distinc stress situations during parturition. Twenty nine canine females were allocated into 3 groups according to the obstetric conditions: eutocia (group 1; n=10), manipulative obstetric assistance or cesarean section (group 2; n=10) and maternal dystocia treated with oxytocin (group 3; n=9). Fifty one neonates were submitted to a clinical evaluation by Apgar scoring and body temperature measurement immediately after birth, at 5 and 60 minutes postnatal; and hemogasometric evaluation, blood glucose and cortisol assay immediately after birth and 60 minutes postnatal. Maternal noninvasive arterial blood pressure, blood glucose and cardiac monitoring were peformed during the first stage of labor, intra-partum, immediately after the last puppy was born and 1 hour later. Neonates from distinct groups showed mixed acidosis in addition to hypoxemia at birth. Neonates remained under metabolic acidosis even after 1 hour of birth due to a detrimental effect on hypoxia. Comparing the results among groups, puppies from group 2 showed significantly lower Apgar score at birth. However, 1 hour later all neonates showed full recovery. Dams subjected to oxytocin infusion showed an increase in blood pressure, hence switching to a normotension status and also presented higher glucose level during parturition. Manipulative obstetric assistance or cesarean section arised neonatal cortisol levels at birth. However, all neonates exhibited significantly lower cortisol concentration after 1 hour of birth. Bitches of group 3 showed significantly higher cortisol level immediatly after whelping. In conclusion, dystocia treated medically by oxytocin infusion resulted in more intense metabolic alterations compared to neonates born under eutocia; oxytocin administration promotes blood pressure enhance, glucose alterations and increase in maternal stress; manipulative obstetric assistance or cesarean section increased neonatal cortisol release at birth.

O parálogo 3 do trocador Na+/H+ (NHE3) é essencial para a reabsorção de HCO3- nos túbulos proximais renais e sua expressão e função adaptam-se às diferentes condições ácido-base do organismo. O objetivo desta tese foi avaliar quais as diferenças entre os efeitos da acidose metabólica (AM) e respiratória (AR) sobre a regulação do NHE3 e identificar variáveis responsáveis pelas respostas adaptativas observadas. Em células OKP, a AM foi simulada diminuindo a [HCO3-] do meio de cultura e a AR aumentando a pCO2 ambiente por 24 h. Foram observados os efeitos das acidoses sobre o RNAm-Nhe3, a presença da proteína-NHE3 na membrana celular e a atividade promotora do gene do Nhe3. Concluiu-se que o pH extracelular não é a variável físico-química responsável por estimular a expressão do NHE3, contudo é um importante candidato à variável responsável por regular o tráfego da proteína para a membrana. Além disso, a região de -471 a -153 pb em relação ao sítio de início de transcrição do promotor do gene do Nhe3 contém prováveis reguladores positivos que atuam em resposta à AM. / The Na+/H+ exchanger 3 (NHE3) is essential for HCO3- reabsorption in renal proximal tubules and its expression and function must adapt to acid-base conditions. The goal of the presente study was to evaluate whether there are differences between metabolic (MA) and respiratory acidosis (RA) with regard to NHE3 modulation and to identify variables that may trigger these distinct adaptive responses. In OKP cells, MA was achieved by lowering [HCO3-] in the cell culture medium and RA by increasing pCO2 in the incubator chamber for 24 h. The effects of both acidosis on Nhe3 mRNA levels, cell-surface NHE3 expression and promoter activity were evaluated. In summary, it was concluded that low extracellular pH is not the physical-chemical variable that up-regulates NHE3 expression, however, extracellular pH is a candidate for the variable related to the NHE3 displacement to the apical membrane. Moreover, the Nhe3 gene promoter region spanning from -471 to -153 base pairs upstream from the transcriptional start site contains putative enhancers regulated in response to MA.

O estudo avaliou os efeitos agudos da Ang-(1-7) na reabsorção de bicarbonato (JHCO3-) no túbulo proximal cortical de rato, in vivo, medindo o pH intratubular pelo microeletródio sensível a H+. O JHCO3- controle é 2,84 ± 0,08 nmol. cm-2. s-1 (49), a Ang-(1-7; 10-12 ou 10-9 M) o reduz (35 ou 61 %) e a Ang-(1-7; 10-6 M) o eleva (56 %). A inibição do receptor Mas (por A779) eleva o JHCO3- (30 %), abole o efeito inibidor da Ang-(1-7), mas não afeta seu efeito estimulador. A inibição do NHE3 (por S3226) diminui o JHCO3- (45 %), não altera o efeito inibidor da Ang-(1-7), mas transforma seu efeito estimulador em inibidor. A concentração de cálcio citosólico ([Ca2+]i), medida pelo FURA-2-AM, controle é 100 ± 2,47 nM (35) e a Ang-(1-7; 10-12, 10-9 ou 10-6 M) a aumenta (152, 103 ou 53 %) transientemente (3 min). A inibição do receptor Mas aumenta a [Ca2+]i (26 %), mais inibe o efeito estimulador de todas as doses de Ang-(1-7). Os resultados indicam que o efeito bifásico dose-dependente da Ang-(1-7) sobre o JHCO3- no túbulo proximal é via receptor Mas e isoforma NHE3 e sugerem estimulação desse trocador por moderado aumento da [Ca2+]i na presença de Ang-(1-7; 10-6 M) e sua inibição por pronunciado aumento da [Ca2+]i na vigência de Ang-(1-7; 10-12 ou 10-9 M). / The action of Ang-(1-7) on bicarbonate reabsorption (JHCO3-) was evaluated in vivo middle proximal tubule of rat kidney, using H ion-sensitive microelectrodes. The control JHCO3- is 2,84 ± 0.08 nmol. cm-2. s-1 (49), Ang-(1-7; 10-12 or 10-9 M) decreases it (35 and 61 %) but Ang-(1-7; 10-6 M) increased it (56 %). A779 (an Ang-(1-7) receptor Mas antagonist) increases the JHCO3- (30 %), prevents the inhibitory effect of Ang-(1-7) and does not affect the stimulatory effect of Ang-(1-7). S3226 (10-6 M; an inhibitor of NHE3) decreases the JHCO3- (45 %), does not affect the inhibitory effect of Ang-(1-7) and changes its stimulatory effect on an inhibitory effect. The control cytosolic free calcium ([Ca2+]i), monitored by FURA-2-AM, is 100 ± 2,47 nM (35) and Ang-(1-7; 10-12, 10-9 or 10-6 M) causes a transient (3 min) increase of it (152, 103 or 53 %). A779 increases the [Ca2+]i (26 %) but impaired the stimulatory effect of Ang-(1-7). Our results indicate the biphasic dose-dependent effect of Ang-(1-7) on JHCO3- in proximal tubule is mediated via Mas receptor and NHE3 and are compatible with stimulation of this exchanger by a moderate increase in [Ca2+]i in the presence of Ang-(1-7, 10-6 M), and its inhibition by large increase in [Ca2+]i with Ang-(1-7, 10-12 or 10-9 M).