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1
Pifferi, Simone. "Calcium Activated Chloride Channels In Olfactory Transduction". Doctoral thesis, SISSA, 2008. http://hdl.handle.net/20.500.11767/4668.
Testo completoAbstract (sommario):
Ca2+-activated Cl ̄ channels are an important component of olfactory transduction. Odorant binding to odorant receptors in the cilia of olfactory sensory neurons (OSNs) leads to an increase of intraciliary Ca2+ concentration by Ca2+ entry through cyclic nucleotide-gated channels. Ca2+ activates a Cl ̄ channel that leads to an efflux of Cl ̄ from the cilia, contributing to the amplification of the OSN depolarization. The molecular identity of this Cl ̄ channel remains elusive. Recent evidences have indicated that bestrophins are able to form Ca2+-activated Cl ̄ channels channels in heterologous systems. Immunohistochemistry revealed that mBest2 was expressed on the cilia of OSNs, the site of olfactory transduction, and co-localized with the main subunit of cyclic nucleotide-gated channels, CNGA2. We performed a functional comparison of the properties of Ca2+-activated Cl ̄ channels from native channels expressed in dendritic knob/cilia of mouse OSNs with those induced by heterologous expression of mBest2 in HEK-293 cells. Even if the two channels did not display identical characteristics, they have many similar features such as the same anion permeability, the Ca2+ sensitivity in micromolar range and the same side-specific blockage of the two Cl ̄ channel blockers commonly used to inhibit the odorant-induced Ca2+-activated Cl ̄ channels in OSNs, niflumic acid and 4-acetamido-4’-isothiocyanato-stilben-2,2’-disulfonate (SITS). However electroolfactogram recording from mBest2 null mice showed a normal sensitivity to odorant stimulation. Therefore mBest2 is a good candidate for being a molecular component of the olfactory Ca2+-activated Cl ̄ channels but its precise role in olfactory transduction remains to be clarified.
2
Dring, Kevin Frederick. "Electrochemical reduction of titanium dioxide in molten calcium chloride". Thesis, Imperial College London, 2006. http://hdl.handle.net/10044/1/8135.
Testo completo
3
Bradley, Jonathan. "Optimisation of anode characteristics of calcium thionyl chloride cells". Thesis, Loughborough University, 1991. https://dspace.lboro.ac.uk/2134/10399.
Testo completoAbstract (sommario):
In the field of high performance primary battery systems lithium anoded cells have been shown to have an excellent performance and extremely good shelf life. The major drawback with the lithium technology is one of safety, whereby abuse conditions (such as charging of the cell) lead to an unstable system with the very real possibility of a cell explosion. For a commercially available cell consideration of safety issues would preclude the marketing of a high performance lithium cell for general use, rather, it will be reserved for specialist e.g. Military use where the personnel having contact with the power source can be trained in its safe operation. The work described in this thesis is concerned with the development of a high performance battery system utilising calcium as the anode material. Calcium has received attention as an anode material for a high performance battery system because it removes many of the safety problems associated with lithium. The major disadvantages of calcium have been addressed namely the shelf life and discharge performance. The electrochemical techniques of cyclic voltammetry and a.c. impedance have been used in conjunction with physical methods such as scanning electron microscopy to define the mode of operation of these cells.
4
Amjad, Asma. "Calcium-activated chloride channels in mouse vomeronasal sensory neurons". Doctoral thesis, SISSA, 2013. http://hdl.handle.net/20.500.11767/3899.
Testo completoAbstract (sommario):
In vomeronasal sensory neurons, signal transduction occurs in microvilli that are present at the neuron’s apical surface. The binding of pheromone to vomeronasal receptors causes an increase of the intracellular calcium concentration by calcium entry through TRPC2. An important issue is the impact of Ca2+ entry in pheromonal transduction.
In the first part of this thesis we have investigated the functional role played by the increase in intracellular Ca2+ concentration in the apical region of vomeronasal sensory neurons. By taking advantage of flash photolysis of caged calcium restricted to the apical region of neurons, we have measured a calcium-activated current with the whole-cell voltage-clamp technique. Our results demonstrated that a large current is indeed activated by calcium in the apical region of mouse vomeronasal sensory neurons and our immunohistochemistry data has revealed the presence of the proteins TMEM16A and TMEM16B, responsible for calcium-activated chloride channels, in the microvilli of vomeronasal sensory neurons. Therefore we have concluded that calcium-activated chloride channels are present at high density in the region where signal transduction occurs and therefore may play an important role in vomeronasal transduction.
In the second part of this thesis we have characterized in more detail the calcium activated currents in mouse vomeronasal sensory neurons using the whole-cell voltage-clamp technique in the presence of various intracellular Ca2+ concentrations. From the dose-response relation we determined that the Ca2+ concentration necessary to activate 50% of the maximal current was 1.4 µM at -100 mV and 0.6 µM at +100 mV. From ion selectivity experiments, we found that the current is carried by anions. Moreover, we demonstrated that some of the commonly used Cl- channel blockers, NFA and CaCCinh-A01, do inhibit the Ca2+-activated current in vomeronasal sensory neurons. Further studies with knockout mice for TMEM16A or TMEM16B will be necessary to establish the physiological role of these channels in vomeronasal transduction.
5
Dirkse, Jason Lennart. "A preliminary study of the effect of calcium chloride highway anti-icer liquid on roadside trees in Leavenworth, Washington". Online access for everyone, 2006. http://www.dissertations.wsu.edu/Thesis/Spring2006/j%5Fdirkse%5F042706.pdf.
Testo completo
6
Moldrzyk, Jan. "Využití vedlejších energetických produktů a dalších druhotných surovin pro výrobu alfa sádry". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226735.
Testo completoAbstract (sommario):
Thesis focus on the longterm research in an area of alpha gypsum production by non pressure method in chloride salt solutions production, which is researched by Institute od technology of building materials and components, Faculty of civil engineering for many years. The result of given research is non pressure equipment for alpha gypsum production. The scope of this research was to make a production of alpha gypsum more efficient through modification of the facility itself and through an optimalization of dehydration process. The scientific aim of this process was to compare an influence of dehydratation solutions of CaCl2, NaCl and KCl on the final product provided that molarity of solutions was at the same level.
7
Girgin, Seref. "Crystallization of alpha-calcium sulphate hemihydrate by aqueous reaction of calcium chloride with sulphuric acid". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102980.
Testo completoAbstract (sommario):
The crystallization of alpha-calcium sulphate hemihydrate with simultaneous regeneration of HCl by controlling the reaction of H 2SO4 (2.6M-8M) with concentrated CaCl2 (1-3.5M) solution at 80°C was investigated. The research included 3 studies: (a) study of the kinetics and mechanism of CaSO4 dehydrate (DH) conversion to hemihydrate (HH) and anhydrite (AH) in variable composition CaCl2 -HCl media; (b) reactive crystallization of alpha-hemihydrate in a semi-batch reactor configuration following the LaMer Diagram concept; and (c) the study of crystal growth and metal uptake by seeded crystallization with and without the presence of several metal chloride salts. According to the first study, AH is the only stable phase in the range of electrolyte concentration and temperature investigated with DH and HH being either metastable or unstable. In the absence of CaCl2 and at 3M HCl concentration or higher DH converts directly to AH. Maintenance of 0.3M or higher CaCl2 concentration was found to render hemihydrate metastable hence making its production feasible. Solubility estimation of three CaSO4 phases with the aid of OLI Stream Analyser software helped to explain the observed phase transition sequence. SEM characterization further revealed the transition from DH to HH to be governed by the topochemical mechanism.In the reactive crystallization study H2SO4 was the limiting reactant added to the CaCl2 solution up to 0.8 SO 4/Ca molar ratio. The nucleation and growth stages were successfully separated via supersaturation control achieved by regulated addition of the limiting reactant in multiple steps. This separation permitted the growth of the homogeneously nucleated crystals within the metastable zone to needle-shaped hexagonal crystals (acicular habit). Upon recycling (seeding) of the product further growth was achieved, producing crystals with 80 mum - volume based mean crystal diameter- or 100-120 mum length and 10-15 mum diameter. Growth of the seed crystals appeared to follow an agglomeration mechanism. However, in the presence of foreign metal cations (in particular divalent, Mg 2+, Fe2+, Ni2+ and trivalent, Al 3+, Fe3+) crystal growth was severely retarded via their apparent adsorption. Some of the metal cations, namely Na+, Ni2+, Al3+ were found to incorporate into the hemihydrate crystal structure to a variable extent from 0.3g/t for Na to 7g/t for Ni and 11g/t for Al. The chloride uptake was less than 10 ppm.
8
Sharma, Aarushi. "HUMAN CLCA2 MODULATES THE CONDUCTANCE OF CALCIUM-ACTIVATED CHLORIDE CHANNELS BY REGULATION OF INTRACELLULAR CALCIUM". OpenSIUC, 2016. https://opensiuc.lib.siu.edu/dissertations/1252.
Testo completoAbstract (sommario):
Chloride channels play an essential role in the physiology of the respiratory system, the gastrointestinal tract, and secretory glands. Their dysregulation underlies debilitating pathologies such as cystic fibrosis, asthma, and certain cancers. The CLCA (Chloride Channel Accessory) gene family is thought to determine severity of these diseases by modulating an unidentified Calcium-activated Chloride Channel (CaCC). Recent evidence indicates Ano1 to be the mediator of strong quintessential calcium-activated chloride current in several cell types. Ano1 is highly expressed in airway epithelium and downregulated in cystic fibrosis patients. Human CLCA2 is also expressed in epithelium of airways and mammary glands, and there it promotes calcium-activated chloride current. Hence, we hypothesized that CLCA2 modulates the conductance of Ano1. We tested this by introducing Ano1 and CLCA2 together or separately into HEK293 cells, which express endogenous Ano1 at a low level. Using whole-cell voltage clamp, we found that CLCA2 enhanced the conductance of the endogenous CaCC. This current was inhibited by a specific inhibitor of Ano1, tannic acid. CLCA2 also increased both the amplitude and the onset rate of the Ano1-mediated current. To determine the mechanism by which CLCA2 amplifies Ano1 mediated current, we used co-immunoprecipitation with or without a protein cross-linking agent and to test whether the interaction if any, was stable or transient, respectively. Neither any interaction, nor any change in Ano1 multimerization was found. We next tested whether CLCA2 enhanced Ano1 conductance by increasing its stability or surface localization. Surface-labelling the cells expressing Ano1 alone or both proteins with biotin, no difference in Ano1 level or surface expression was detected. Ano1 has recently been shown to be activated by intracellular calcium released from endoplasmic reticulum (ER) stores and by subsequent store-operated calcium entry (SOCE). Therefore, we investigated whether CLCA2 could increase intracellular calcium levels. With Fluo-4 dye calcium imaging, we found that CLCA2 expression enhanced both ER calcium stores and SOCE upon exhaustion of intracellular stores, and the SOCE response could be abolished by a specific inhibitor of SOCE, BTP-2. This inhibitor also abolished CLCA2-induced chloride current, establishing that CLCA2 enhances CaCC via SOCE. Moreover, knockdown of CLCA2 in MCF10A cells, that naturally express both proteins, reduced both ER calcium stores and SOCE. Mutations that abolished the metalloprotease activity of CLCA2 or deleted the cytoplasmic tail had little effect on its enhancement of chloride current or intracellular calcium, suggesting that the uncleaved ectodomain was responsible for both effects of CLCA2. Since, the ectodomain is the most conserved region of the protein, we found that another member of the CLCA family, CLCA1, was also effective in enhancing intracellular calcium storage and SOCE. Co-immunoprecipitation studies further revealed that CLCA2 interacts in a ternary complex with mediators of SOCE, STIM1 and ORAI1. These results explain the CaCC-enhancing effects of CLCA family members and suggest a broader role in other calcium-dependent processes. Understanding the modulatory relationship between these molecules may lead to better therapies for airway diseases and Ano1-dependent cancers. Furthermore, the discovery that CLCA2 regulates intracellular calcium levels may explain its effects on cellular differentiation, stress response, and cell death.
9
Rao, Kartik. "The electrochemical reduction of titanium oxides in molten calcium chloride". Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501782.
Testo completo
10
Gamble, Joanne M. "Field evaluation of calcium nitrite and chloride in Ohio prestressed concrete box beam bridge girders". Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178652761.
Testo completo
11
Lu, Ying. "Effects of sodium chloride salting and substitution with potassium chloride on whey expulsion of cheese". DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1285.
Testo completoAbstract (sommario):
The rate and extent of syneresis (whey expulsion) strongly affects cheese composition and quality. During salting, curd syneresis is influenced by the combined effect of both osmotic pressure and protein hydration. Our objective is to examine how cheese composition and whey expulsion are influenced by dry salting curd at various intervals, levels, applications, and potassium chloride (KCl) substitution, or change in calcium or sodium level in test solution (i.e., whey-brine). Four sets of unsalted fresh Cheddar curds were salted with different methods, with at least 3 replicates of each set on separate days. Set A was salted with 30 g/kg NaCl over 3 applications, either 5 or 10 min apart. Set B was salted with 30, 25, and 20 g/kg NaCl over 3 applications 5 min apart. Set C was salted with 20 g/kg NaCl using 1, 2, or 3 applications. Set D received salt consisting of a 2:1 molar ratio of NaCl and KCl over 3 applications 5 min apart. Whey was collected every 5 or 10 min until 30 or 40 min after the start of salting and subsequently pressed for 3 h. Using 10-min intervals delayed whey syneresis but after pressing there was no significant influence on final cheese composition. Decreasing salt levels significantly reduced the amount of whey expelled prior to pressing and resulted in cheeses with higher moisture and slightly lower pH. Adding salt over different applications did not significantly affect cheese composition. Partial substitution with KCl did not affect the amount of whey expelled or cheese moisture composition. Salted milled Cheddar cheese curd was immersed at 22°C for 6 or 18 h in test solution, with the addition of 1, 5, 10, or 20 g/L calcium, and 15 g/L salt. After immersion, curd weight change, moisture, pH, sodium, serum calcium and total calcium levels were measured. When calcium levels in solution increased, curd moisture, pH, and weight gain decreased while serum and total calcium levels increased significantly. Similarly, unsalted milled Cheddar cheese curds were immersed at 22°C for 6 h in test solution with 30, 60, 90, or 120 g/L salt in addition to 6 g/L calcium. The salt level in solution was inversely proportional with weight change, moisture, and salt level of curd.
12
Jegede, Oluyemi. "Concept design of a thermo-chemical heat pump using calcium chloride-NH₃ and magnesium chloride-NH₃ working pairs". Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/97979/.
Testo completoAbstract (sommario):
This work presents the design of a double effect thermochemical heat pump based on the calcium chloride-ammonia and magnesium chloride-ammonia working pairs. The work began with a comprehensive theoretical and literature review of the similar systems which exist in the literature. Once the literature review was done, a large temperature jump experimental rig was built in order to be able to determine the behaviour of the relevant working pairs. Even though the focus of the work is thermochemical reactions, the activated carbon-ammonia pair was first used to validate the large temperature jump rig. The reason for this is that the activated carbon-ammonia pair is better understood compare to the thermochemical reactions. The experiments on the activated carbon- ammonia pair yielded some useful results. The results obtained show that two heat transfer properties (thermal conductivity, k and heat transfer coefficient, h) with physical meaning can be extracted from large temperature jump data. Furthermore, the change in thermal conductivity with the packing density of the adsorbent was investigated. The general trend was one of increasing thermal conductivity as the packing density was increased, the thermal conductivity increased from 0.2Wm‾¹K‾¹ to 0.4Wm‾¹K‾¹ as the packing density was increased from 530kgm‾³ to 705kgm‾³. When the calcium chloride-ammonia and magnesium chloride-ammonia working pairs were investigated in the large temperature jump setup, the kinetic parameters for each respective reaction were obtained. This enabled the development of a dynamic model of a representative thermochemical heat pump based on the aforementioned working pairs. The dynamic model helped to investigate the performance of the heat pump under various operating conditions. The coefficient of performance (COP) and the specific heating power ranged from 1.21 to 1.40 and 40W/litre to 400W/litre respectively depending on the operating conditions.
13
Calta, M. "Early development and gill function in freshwater fish". Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307766.
Testo completo
14
Adair, Jeanette. "Alternate channel therapy for the pancreatic disease of Cystic Fibrosis". Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251005.
Testo completo
15
Li, Zhibao 1962. "Measurement and chemical modeling of calcium sulfate solubilities in concentrated chloride media". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102677.
Testo completoAbstract (sommario):
Measurement and chemical modeling of CaSO₄ solubilities in HCl-containing multi-component aqueous chloride solutions have been thoroughly investigated. Solubilities of calcium sulfate dehydrate, hemihydrate and anhydrite in concentrated HCl (up to 12 mol·dm⁻³), CaCl₂ (up to 3.5 mol·dm⁻³) and their mixed aqueous solutions were experimentally determined by using the classic isothermal dissolution method at the temperature range from (283 to 353) K. A self-consistent chemical model based on a single set of model parameters for all three CaSO₄ modifications was developed with the aid of OLI Systems software platform. This was accomplished via regression of experimental solubility data that led to the determination of new Bromley-Zemaitis model parameters for the Ca²⁺---SO₄²⁻ and Ca²⁺ --HSO₄⁻ ion pairs. The model was successfully tested for the estimation of CaSO₄ solubilities in concentrated (up to 20 mol·kg⁻¹) HCl-CaCl₂-H₂O systems up to 373 K. In addition this newly developed OLI-based chemical model was successfully applied to construct the CaSO₄ phase transition diagrams in the HCl-CaCl₂-H₂O system. The effect of various chloride salts (NaCl, MgCl₂, FeCl₂, AlCl₃ and FeCl₃) on the solubility of CaSO₄ phases in aqueous HCl or HCl + CaCl₂ solutions up to 353 K was further investigated by experiment and modeling. This led to the development of a truly global model of CaSO₄ solubility in the H + Na + Ca + Mg + Al + Fe(II) + Cl + SO₄+ H₂O system. The new model makes use of new Bromley-Zemaitis activity coefficient model parameters for many ion pairs consisting of cations (Na⁺, Mg²⁺, Fe²⁺, and Al³⁺) and anions (SO₄⁻, HSO₄⁻, and Al(SO₄)₂⁻), as well as new empirical dissociation constant parameters for the species, MgSO₄(aq), AlSO₄⁺, and Al(SO₄)²⁻. The new model was shown to successfully predict the solubility of calcium sulfate phases in multi-component systems not used in model parameterization.
16
Williamson, George D. "Hexaminecobalt (III) chloride and ruthenium red inhibited calcium uptake in nervous tissue". DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1991. http://digitalcommons.auctr.edu/dissertations/521.
Testo completoAbstract (sommario):
The effects of ruthenium red and hexaminecobalt (III) chloride on Ca2+ transport and mitochondrial respiration were studied. Low levels of ruthenium red and hexaminecobalt (III) chloride (3-6 nmoles/ng mitochondrial protein) completely inhibited the stimulation of respiration by Ca2+ but had no effect on State 3 respiration. Ruthenium red and hexaminecobalt also inhibited respiration-dependent and ATP-supported Ca2+ uptake as well as the metabolism-independent and high- and low-affinity binding of Ca2+; although, neither had an effect on the release of accumulated Ca2+. Concentrations higher than (7 nmoles/mg mitochondrial protein) prevent Ca2+ binding and transport; markedly inhibit/alter hexaminecobalt (III) chloride and ruthenium red (state 4) respirations, but however, did not prevent stimulation of respiration by ADP.
17
Choi, Michael Shui Kuen. "The involvement of calcium and chloride ions in rat Leydig cell steroidgenesis". Thesis, University College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244247.
Testo completo
18
Alsharari, Musaed Amish. "Reclamation of fine-textured sodic soil using gypsum, langbeinite, and calcium chloride". Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/282872.
Testo completoAbstract (sommario):
The effects of various application rates of gypsum (Aqua-cal = finely ground gypsum), langbeinite (K₂SO₄.2MgSO₄), and CaCl₂ (anhydrous) on exchangeable Na removal and saturated hydraulic conductivity of a sodic soil were investigated under laboratory batch studies and laboratory column leaching studies. The research involved four phases of studies. Characterization of the soil and irrigation water indicated that the soil sample is sodic (ESP=35.3), ECₑ = 3.36 dS/m), and the irrigation water is moderately saline (EC = 2.2 dS/m). The laboratory batch studies showed that CaCl₂ and langbeinite treatments were more efficient in the displacement of Na than gypsum which increased with increasing application rate. In contrast, with gypsum, Na displacement increased to a maximum at an application rate of 7 tons/ha; then, no further increase in displacement was observed above that level. In the column leaching studies, applied amendments at equivalent rates of 7 tons/ha each and leaching with 5 pore volumes of irrigation water resulted in a total Na displacement of 60%, 80%, and 84% for gypsum, langbeinite, and CaCl₂, respectively. Moreover, the SAR of the soil was reduced significantly in the above treatments from 34.5 in the beginning of leaching to 6.80 for gypsum (G7), from 41.8 to 5.60 for langbeinite (L₇), and from 32.6 to 2.5 for CaCl₂(7). When amendments were applied at higher rates (G7 tons/ha gypsum and 13 tons/ha of each of CaCl₂ and langbeinite), the % total Na displaced was 60%, 100%, and 94% for gypsum, langbeinite, and CaCl₂, respectively. The corresponding SAR values at the end of reclamation were 6.80, 4.50, and 5.50 for gypsum, langbeinite, and CaCl₂, respectively. The combination treatments significantly improved the reclamation at 0.05 level as compared to the G7 treatment alone and saved more leaching water and displaced higher exchangeable Na as compared to the gypsum treatment (G7) alone. Saturated hydraulic conductivity (Ks) studies indicated that Ks was increased significantly when the amendments were applied at equivalent weights (7 tons/ha) and at higher application rates as compared to the control. The Ks of the gypsum treated soil (G7) was significantly higher than Ks of langbeinite and CaCl₂ treated soil at both equivalent rates and when applied at higher rates L13 and CaCl₂(13).
19
Ozhathil, Lijo Cherian. "A structural and functional insight into TMEM16B, a calcium-activated chloride channel". Doctoral thesis, SISSA, 2014. http://hdl.handle.net/20.500.11767/3921.
Testo completoAbstract (sommario):
TMEM16B, also known as anoctamin 2 has been recently identified as a calcium-activated chloride channel. It is expressed at the synaptic terminals of photoreceptors, in hippocampal cells, in the cilia of olfactory sensory neurons and in the microvilli of vomeronasal sensory neurons. TMEM16B, as its most known cousin TMEM16A, is activated both by calcium and voltage. When this thesis was started there was no available data correlating the gating function and protein structure in TMEM16B.
In our first manuscript, we show a coupling between calcium and voltage in TMEM16B activation. Primary sequence analysis did not show any canonical calcium binding sites nor S4-like dedicated voltage sensors. However, the first intracellular loop contains several negatively charged amino acids. We performed site directed mutagenesis at 367E, and 386EEEEE390 in the first intracellular loop and investigated their role in calcium or voltage dependence of TMEM16B. Either neutralizing or deleting these acidic residues strongly shifted the conductance-voltage relation towards more positive voltages without a significant effect on the apparent calcium sensitivity. Our findings indicate involvement of glutamic acids from the first intracellular loop in voltage dependent activation of TMEM16B, and provides an initial structure-function study for this channel.
In our second manuscript, we focused on understanding the effect of permeant anions on TMEM16B activation. Our results show TMEM16B is poorly selective among anions and has a permeability sequence of SCN- > I- > NO3- > Br- > Cl- > F- > gluconate. The channel kinetics also shows dependence on the permeant anion, with more permeable anions, such as SCN-, causing a much slower activation and deactivation kinetics than Cl-. Moreover, SCN- facilitated the channel activation by
lowering the half-maximal concentration of calcium required for opening the channel and shifting the conductance-voltage relation towards less positive voltages. From this work we report the existence of a crosstalk between calcium, voltage and permeant anion in TMEM16B activation.
Furthermore, we looked for a compound that could modulate the function of TMEM16B. We found that anthracene-9-carboyxlic acid, one of the traditional calcium-activated chloride channel blockers is very interesting since it had multiple effects on TMEM16B. In our third manuscript we report the block by A9C as voltage and concentration dependent, with maximal inhibition at positive voltages. Surprisingly, A9C also potentiated the current at intermediate concentrations and negative voltages. However, anthracene-9-methanol (A9M), a non-charged analog of A9C, completely abolished the voltage dependent inhibition and the potentiation effect seen with A9C. Both A9C and A9M had much slower current kinetics. This indicates the requirement of negative charge of A9C for its voltage dependent block of outward currents and potentiation of inward currents.
In summary, the studies included in this thesis reveal a complex coupling between calcium, voltage, and permeant anion in TMEM16B activation. The identification of a compound have contrasting effects on the channel activation, provides a new tool for future structure-function studies on this channel.
20
Vidal, Vitor Andre Silva 1991. "Efeito da redução de cloreto de sódio e fosfato sobre as propriedades funcionais de emulsões cárneas adicionadas de sais substitutos". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255102.
Testo completoAbstract (sommario):
Orientador: Marise Aparecida Rodrigues PollonioDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Com o aumento das informações científicas sobre a relação entre a quantidade e composição de alimentos consumidos na dieta e a saúde, a busca por alimentos mais saudáveis tornou-se relevante nas escolhas dos consumidores. A carne e os produtos cárneos são excelente fonte de oligoelementos, proteínas de alto valor biológico, minerais, vitaminas do grupo B e outros compostos bioativos. Porém, os elevados níveis de ácidos graxos saturados, colesterol, gordura, aditivos e, especialmente sódio tem imposto limites ao seu consumo. Neste contexto, o objetivo deste trabalho foi avaliar a redução do teor de cloreto de sódio (NaCl), principal fonte de sódio e tripolifosfato de sódio (TPFS) em emulsões cárneas de baixo custo (alto teor de carne de frango mecanicamente separada) e em formulações nobres (alto teor de matéria-prima cárnea). O estudo foi dividido em duas etapas. Na primeira, foram elaboradas emulsões cárneas populares (60% de carne de frango mecanicamente separada) contendo sais substitutos (NaCl, KCl e CaCl2) combinados ou isolados com base na força iônica correspondente a 2,5% de NaCl, e formulações com apenas redução de 50% destes sais e TPFS com objetivo de avaliar o efeito sobre as propriedades físico-químicas. Na segunda etapa, foram elaborados 5 tratamentos que apresentaram melhor desempenho na primeira etapa, contendo formulações com blend de sais (NaCl, KCl e CaCl2), e redução de 50% de NaCl e TPFS em emulsões cárneas com alto teor de matéria-prima cárnea. O objetivo da segunda etapa foi igualmente utilizar blends de sais como estratégia para reduzir parcialmente o teor de NaCl e TPFS em emulsões cárneas elaboradas com alto teor de matéria-prima cárnea e verificar o efeito destes nas características físico-químicas a fim de que as matrizes cárneas pudessem ser comparadas. Na primeira e segunda etapa foram determinados: teores de Na, K e Ca, estabilidade de emulsão, pH, avaliação da cor instrumental, Aw, microestrutura e perfil de textura. O KCl foi reportado como o melhor sal substituto ao NaCl, não tendo diferença ou resultando somente em pequenas diferenças em relação aos tratamentos contendo apenas NaCl. O sal substituto CaCl2 causou efeito negativo nas características da matriz cárnea, principalmente na porcentagem de extração das proteínas miofibrilares, ainda que com a mesma força iônica que NaCl. O uso de blend de sais (50% NaCl, 25% KCl e 25% CaCl2) mostrou-se ser uma boa alternativa para redução de sódio. Desta forma, a combinação de sais substitutos (50% NaCl, 25% KCl e 25% CaCl2) e utilização do KCl como sal substituto ao NaCl apresentou-se como uma alternativa para redução de sódio tanto em emulsões cárneas com alto teor de matéria-prima cárnea quanto em emulsão cárnea com alto teor de CMS. No entanto, a redução de fosfato em formulações populares com redução de sódio e adicionada de sais substitutos deve ser melhor investigada para ser implementada
Abstract: The scientific and technological development on food composition and its relationship with food intake and health has led consumer to make healthier food choices. Meat and meat products are excellent source of trace elements, protein with high biological value, minerals, B vitamins and other bioactive compounds. However, their high levels of saturated fatty acids, cholesterol, fat, additives and especially sodium have imposed limits on consumption. In this context, the aim of this study was to evaluate the reduction of sodium chloride (NaCl), the main source of sodium, and sodium tripolyphosphate (STPP) in low-cost meat emulsions (high content of mechanically separated poultry meat) and noble formulations (high content of meat raw material). The study was divided into two stages. First, popular meat emulsions were prepared (60% of mechanically deboned poultry meat) containing salts substitutes (NaCl, KCl and CaCl2) alone or in combination, corresponding to ionic strength of 2.5% NaCl. Then, formulations containing 50% of these salts and STPP were also prepared to evaluate the effect of salt reduction on the physicochemical properties of the processed products. In the second stage, the five treatments with the best performance were prepared, containing blend of salts (NaCl, KCl and CaCl2), and 50% reduction of NaCl and STPP in meat emulsions with high content of meat raw material. The second stage aimed to utilize blends of salts as a strategy to partially reduce NaCl and STPP in meat emulsions containing high content of meat raw material, and to verify its effect on the physicochemical characteristics and compare the meat matrices. In both stages, Na, K and Ca, emulsion stability, pH, instrumental color, aw, microstructure and texture profile were determined. The KCl was reported as the best substitute to NaCl, once little differences were observed in the treatments containing only NaCl. The salt substitute CaCl2 caused a negative effect on the characteristics of the meat matrix especially in the percentage of myofibrillar proteins extracted, despite the similar NaCl ionic strength of all formulations. The use of salt blend (50% NaCl, 25% KCl, and CaCl2 25%) proved to be a good alternative to sodium reduction. Thus, the combination of salt substitutes (50% NaCl, 25% KCl, and 25% CaCl2) and the use of KCl as NaCl substitute may be an alternative to sodium reduction in both emulsions with a high content of meat raw material as with high content of mechanically deboned poultry meat. However, further studies are required on the phosphate reduction in the popular formulations containing low sodium and salt substitutes
Mestrado
Tecnologia de Alimentos
Mestre em Tecnologia de Alimentos
21
Meagher, Thomas F. "Effect of Dosage of Non-Chloride Accelerator versus Chloride Accelerator on the Cracking Potential of Concrete Repair Slabs". Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5743.
Testo completoAbstract (sommario):
Due to strict placement time and strength constraints during the construction of concrete pavement repair slabs, accelerators must be incorporated into the mixture design. Since the most common accelerator, calcium chloride, promotes corrosion of concrete reinforcement, a calcium nitrate-based accelerator was studied as an alternative. To replicate mixtures used in the field, commercial accelerators commonly used in concrete pavement repair slabs were used in the current study. Crack risk of different mixtures was assessed using modeling and cracking frame testing. HIPERPAV modeling was conducted using several measured mixture properties; namely, concrete mechanical properties, strength-based and heat of hydration-based activation energies, hydration parameters using calorimetric studies, and adiabatic temperature rise profiles. Autogenous shrinkage was also measured to assess the effect of moisture consumption on concrete volume contraction. The findings of the current study indicate that the cracking risk associated with calcium nitrate-based accelerator matches the performance of a calcium-chloride based accelerator when placement is conducted during nighttime hours.
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Lehle, Fredric, W. C. Hofmann e Bonnie Guhy. "Effect of Calcium Nitrate and Calcium Chloride on the Primary Root Growth of Cotton Seed Imbibed at Low Temperatures". College of Agriculture, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/204457.
Testo completoAbstract (sommario):
The effect of various concentrations of calcium nitrate and calcium chloride on the primary root (radicle) growth of cotton seed at a suboptimal temperature was evaluated 14 days after imbibition onset under laboratory conditions. Both forms of calcium at concentrations up to 10 mM enhanced cotton seed radicle growth at 15 C.
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Choi, Hyung Jun. "Soil stabilization using optimum quantity of calcium chloride with Class F fly ash". Texas A&M University, 2005. http://hdl.handle.net/1969.1/4287.
Testo completoAbstract (sommario):
On-going research at Texas A&M University indicated that soil stabilization
using calcium chloride filter cake along with Class F fly ash generates high strength.
Previous studies were conducted with samples containing calcium chloride filter cake
and both Class C fly ash and Class F fly ash. Mix design was fixed at 1.3% and 1.7%
calcium chloride and 5% and 10% fly ash with crushed limestone base material.
Throughout previous studies, recommended mix design was 1.7% calcium chloride filter
cake with 10% Class F fly ash in crushed limestone base because Class F fly ash
generates early high and durable strength.
This research paper focused on the strength increase initiated by greater than
1.7% pure calcium chloride used with Class F fly ash in soil to verify the effectiveness
and optimum ratio of calcium chloride and Class F fly ash in soil stabilization. Mix
design was programmed at pure calcium chloride concentrations at 0% to 6% and Class
F fly ash at 10 to 15%.
Laboratory tests showed samples containing any calcium chloride concentration
from 2% to 6% and Class F fly ash content from 10% to 15% obtained high early strength however, optimum moisture content, different mix design, and mineralogy
deposit analysis are recommended to evaluate the role and the effectiveness of calcium
chloride in soil stabilization because of the strength decreasing tendency of the samples
containing calcium chloride after 56 days.
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Fosu, Allen Yushark. "Development of a Chloride Route for Lithium Extraction from Spodumene". Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0094.
Testo completoAbstract (sommario):
Le lithium est un composant majeur des batteries Li-ion, utilisées dans la fabrication de nombreux appareils électroniques portables. La transition énergétique entraîne le passage des véhicules thermiques aux véhicules électriques et hybrides, qui repose principalement sur l'utilisation de batteries Li-ion pour le stockage réversible de l'énergie. Le développement des véhicules électriques basés sur la technologie lithium-ion est à l'origine d'une demande record de sel de lithium (principalement carbonate et hydroxyde de lithium). Le spodumène est la principale source de lithium à partir de minerais. Son traitement nécessite une transformation de phase de la forme α à la forme β, suivie d'un grillage conduisant à la formation d'un sel de lithium après des étapes de lixiviation, de purification et de récupération. Dans cette thèse, le concentré de spodumène de la région de Pilbara en Australie occidentale a été caractérisé pour le traitement thermique et hydrométallurgique. Le traitement thermique est responsable de la formation de fissures dans les grains qui deviennent plus visibles avec l'augmentation de la température. La désintégration du matériau, la fusion et l'agglomération avec les minéraux contenus dans la gangue ont également été observées en augmentant la température jusqu'à 1050 °C. Des énergies d'activation apparentes de 655±20 kJ mol-1 ont été calculées pour la transformation de l'α-spodumène, ce qui confirme une forte dépendance à la température pour les transformations polymorphes du spodumène. Par la suite, nous avons étudié une voie alternative aux méthodes conventionnelles (procédé à l'acide sulfurique) pour traiter le concentré de spodumène dans le but de réduire la consommation d'énergie élevée des étapes de transformation de phase et de grillage au sulfate. Pour ce faire, nous avons procédé à la chloration directe de l'α-spodumène avec du chlorure de calcium, suivie d'une lixiviation à l'eau du résidu pour récupérer le chlorure de lithium. L'analyse du résidu obtenu après lixiviation a indiqué que la forme α était le seul polymorphe présent, ce qui suggère que l'extraction se fait directement à partir de la phase α. Dans des conditions optimales, un traitement thermique à 1000 °C pendant 60 minutes du concentré de spodumène en présence de chlorure de calcium à un rapport molaire chlorure de calcium/spodumène de 2,0 est nécessaire pour extraire près de 90 % du lithium et récupérer 85 % dans la liqueur de lixiviation. Une énergie d'activation apparente d'environ 122±6 kJ mol-1 a été calculée pour des températures allant de 800 à 950 ℃. La liqueur obtenue après lixiviation a été purifiée par échange d'ions et extraction par solvant afin de récupérer du chlorure de lithium d'une pureté suffisante pour être considéré comme un précurseur dans la production de matériaux pour batteries au lithium-ionLithium is a major component of Li-ion batteries, used in the manufacture of many portable electronic devices. The energy transition is driving the shift from thermal to electric and hybrid vehicles, which relies mainly on the use of Li-ion batteries for reversible energy storage. The development of electric vehicles based on lithium-ion technology is responsible for a record demand for lithium salt (mainly lithium carbonate and hydroxide). Spodumene is the main source of lithium from ores. Its processing requires a phase transformation from α-form to β-form, followed by roasting leading to the formation of a lithium salt after a leaching, purification, and recovery steps. In this thesis, spodumene concentrate from the Pilbara region of Western Australia was characterized for thermal and hydrometallurgical processing. Heat treatment is responsible for the formation of cracks in the grains which become more noticeable with increasing temperature. Disintegration of the material, melting and agglomeration with minerals contained in the gangue have also been observed by increasing the temperature up to 1050 °C. Apparent activation energies of 655±20 kJ mol-1 was calculated for the transformation of α-spodumene which confirms a strong temperature dependence for polymorphic transformations of spodumene. Subsequently, we investigated an alternative route to conventional methods (sulphuric acid process) to treat the spodumene concentrate with the aim of reducing the high energy consumption of the phase transformation and sulphate roasting steps. This was achieved by direct chlorination of α-spodumene with calcium chloride, followed by water leaching of the residue to recover lithium chloride. Analysis of the residue obtained after leaching indicated that the α-form was the only polymorph present, suggesting that extraction occurs directly from the α-phase. Under optimal conditions, heat treatment at 1000 °C for 60 minutes of the spodumene concentrate in the presence of calcium chloride at a calcium chloride/spodumene molar ratio of 2.0 is required to extract nearly 90% of lithium and recover 85% in the leach liquor. An apparent activation energy of about 122±6 kJ mol-1 was calculated for temperatures ranging from 800 to 950 ℃. The liquor obtained after leaching was purified by ion exchange and solvent extraction to recover lithium chloride of sufficient purity for consideration as a precursor in the production of lithium-ion battery materials
25
Saleh, Sohag Nafis. "A study of the calcium activated chloride current in murine smooth muscle cells". Thesis, St George's, University of London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434989.
Testo completo
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Wefelmeyer, Winnie. "Calcium and chloride dynamics in immature neurons and their role in dendritic growth". Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:5b67b345-8469-4370-8e3f-68bef6a629e9.
Testo completoAbstract (sommario):
Activity-dependent dendritic development is an important process in the maturation of neuronal circuits. The precise morphology of a neuron’s dendritic tree dictates which other cells it is able to interact with and how it will receive and process synaptic information. The aim of this Thesis was to investigate the mechanisms by which dendrites grow and, in particular, how changes in intracellular ion concentrations contribute to these mechanisms. One important activity-dependent signal is calcium as it can translate neuronal activity into morphological changes. Despite this, very little is known about calcium signalling during the period of dendritic development. Using single-cell electroporation of immature CA1 hippocampal pyramidal neurons, I characterised the spatial and temporal properties of local calcium transients in growing dendrites. This revealed a high frequency of transients at shaft filopodia and stable branchpoints, but an almost complete absence from the tips of dendritic branches. Another important factor during development is the intracellular chloride concentration because this regulates neuronal excitability. Prematurely lowering intracellular chloride by expressing the chloride co-transporter KCC2 led to less stable dendritic filopodia and stunted dendritic growth. These effects were independent of local calcium signalling and suggested that chloride regulation itself may be fundamental to normal dendritic growth. To examine this further I developed imaging techniques to measure the spatial and temporal dynamics of chloride in growing dendrites. This work revealed a somatodendritic gradient of increasing intracellular chloride, whereby the highest concentrations were found at sites of growth. Further analysis suggested a close link between local chloride regulation and morphological changes. The dendritic tips that exhibited high intracellular chloride levels and the potential to rapidly modulate these levels, also exhibited the greatest morphological dynamics. These findings have important implications for understanding the mechanisms of dendritic growth and establish the spatiotemporal regulation of chloride as a key parameter.
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Steger, Laurent. "Etude de l'accélération des ciments à haute teneur en laitier de haut-fourneaux par du chlorure de calcium". Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30333.
Testo completoAbstract (sommario):
Les laitiers de hauts fourneaux sont un coproduit de l'industrie métallurgique, utilisés dans les ciments composés (CEM II & III) en substitution partielle du clinker portland et reconnus notamment pour leurs avantages en termes d'abaissement de chaleur d'hydratation, d'augmentation des performances de durabilité et de réduction du bilan carbone des bétons. Bien qu'atteignant des performances mécaniques ultimes comparables voire supérieures au ciment portland (CEM I), les liants proposant de forts taux de laitier voient le développement de leur résistance mécanique fortement ralenti. Ce phénomène s'explique par une réactivité plus faible du laitier qui nécessite des conditions "d'activation" pour réagir correctement. Il existe divers additifs ayant pour effet d'accélérer le durcissement des ciments, parmi lesquels le chlorure de calcium montre les meilleures performances. Les effets du chlorure de calcium sont particulièrement importants durant les premiers jours de l'hydratation. Cependant, leur usage est fortement règlementé en raison de l'effet corrosif du chlore sur les aciers du béton armé. Les objectifs de la thèse visent à étudier les mécanismes d'action du chlorure de calcium sur les matrices ciment-laitier durant les premiers jours d'hydratation. Un panel de techniques expérimentales a été utilisé pour identifier spécifiquement l'action des chlorures sur le laitier et le ciment. Des couplages DRX-Analyse d'Images MEB et RMN montrent que le chlorure de calcium entraîne une précipitation accélérée de portlandite et d'ettringite, issus de l'augmentation du taux de réaction du clinker. Le démarrage de la réaction du laitier s'opère après environ 12 heures, et n'est pas impacté par le chlorure de calcium. En revanche, le taux de réaction du laitier augmente en présence de l'accélérateur. On observe la formation rapide, importante et exclusive de Sels de Friedel en présence de chlorure, en remplacement des AFm sulfatés et/ou carbonatés. L'augmentation du taux de réaction des phases anhydres entraîne la précipitation de C-S-H supplémentaire. Cette formation de Sels de Friedel et de C-S-H provoquent un remplissage plus rapide de la porosité et l'augmentation des performances mécaniquesBlast furnace slags are a co-product of the metallurgical industry, used in composite cements (CEM II & III) as a partial substitution for Portland clinker and recognized in particular for their advantages in terms of lowering the heat of hydration, increased durability performance and reduced carbon footprint of concrete. Although achieving ultimate mechanical performance comparable to or better than Portland cement (CEM I), binders offering high levels of slag see the development of their mechanical strength greatly slowed down. This phenomenon is explained by a lower reactivity of the slag which requires "activation" conditions to react properly. There are various additives that accelerate the hardening of cements, among which calcium chloride shows the best performance. The effects of calcium chloride are particularly important during the first days of hydration. However, their use is strongly regulated because of the corrosive effect of chlorine on steels of reinforced concrete. The objectives of the thesis are to study the mechanisms of action of calcium chloride on cement-slag binders during the first days of hydration. A panel of experimental techniques has been used to specifically identify the action of chlorides on slag and cement. Coupled results from XRD-NMR SEM experiments show that calcium chloride causes an accelerated precipitation of portlandite and ettringite, resulting from the increase in the reaction rate of clinker. The start of the slag reaction takes place after about 12 hours, and is not impacted by the calcium chloride. On the other hand, the reaction rate of the slag increases in the presence of the accelerator. The rapid, significant and exclusive formation of Friedel salts in the presence of chloride is observed, replacing sulphated and / or carbonated AFm. Increasing the reaction rate of the anhydrous phases results in the precipitation of additional C-S-H. This formation of Friedel salts and C-S-H causes a faster filling of the porosity and the increase of the mechanical performances
28
Naduvath, Anu Paul. "Removal and recovery of phosphorus from side-stream hydrolysis". Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210715.
Testo completoAbstract (sommario):
The report formulates the experiments conducted to remove phosphorus from the return sludge wastewater subjected to side-stream hydrolysis. The experiments are conducted using the wastewater from the outlet of side-stream hydrolysis and is tested in a laboratory at the Duvbackens wastewater treatment plant in Gävle. Chemical precipitation is used in the experiments and displays remarkable results using magnesium chloride and calcium chloride as the precipitants. A successful removal rate of 79-99% is achieved through this method. The phosphate phosphorus content is chosen to be the criterion for estimating the phosphorus removal rate. Possible parametric variations are also reviewed in the report. The decline in ammonium nitrogen is also studied alongside. Struvite and calcium phosphate are the possible precipitates and are recovered with the prospect of recycling. Both the precipitates are known as slow fertilizers and are used in the agricultural industry. If recovered by proper means, these precipitates can reduce the pressure on phosphate industry and on naturally occurring phosphate rocks. Calcium phosphate is selected among the precipitation methods for its rapid reaction and its minimum response to parametric variations. It also expresses a faster settling property with a clear solution after precipitation. The removal and recovery of phosphorus from the side-stream hydrolysis is evaluated with a notion to operate in a pilot scale.
29
Bortoluzzi, Eduardo Antunes. "Influência do cloreto de cálcio no tempo de presa, solubilidade, desintegração, pH e atividade antimicrobiana do MTA e do cimento Portland branco com radiopacificador /". Araraquara : [s.n.], 2007. http://hdl.handle.net/11449/104186.
Testo completoAbstract (sommario):
Resumo: O objetivo deste estudo foi avaliar a influência do acréscimo de 10% de cloreto de cálcio (CaCl2) no tempo de presa, solubilidade, desintegração, pH e atividade antimicrobiana do MTA Branco (MTA) e cimento Portland branco com radiopacificador (CPB). O ProRoot MTA (PRO), com e sem CaCl2, também foi incluído no teste de atividade antimicrobiana. O teste do tempo de presa inicial seguiu a especificação #57 da ADA e o do tempo de presa final a da ASTM (C266-03). Para os testes de solubilidade, desintegração e pH foram utilizados 6 anéis de teflon para cada cimento, medindo 4 mm de espessura e 12 mm de diâmetro interno com parede de 2 mm. Depois de preenchidos, os anéis foram mantidos por 24 e 72 h e 7, 14 e 28 dias em água MiliQ, que foi renovada no fim de cada período. Após cada período, os cimentos foram desidratados em dessecador com sílica por 24 h. Foi registrado o peso de cada cimento hidratado e desidratado. O pH da água onde os cimentos permaneceram imersos foi medido por um pHmetro. A atividade antimicrobiana foi avaliada pela técnica da difusão em ágar, empregando o método do poço. Os microrganismos utilizados foram procedentes da ATCC: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Candida albicans, Staphylococcus epidermidis. O acréscimo do CaCl2 proporcionou uma diminuição de 50% do tempo de presa inicial dos cimentos. Já o tempo de presa final do MTA foi diminuído em 35,5% e o do CPB em 68,5%. Os resultados do teste de solubilidade mostraram que o MTA+CaCl2 absorveu água e não perdeu peso com o passar do tempo, exceto no período de 24 h. O MTA, tanto hidratado quanto desidratado, perdeu peso, mas com valores aceitáveis pela ADA. O CPB apresentou maior solubilidade, a qual foi diretamente proporcional ao tempo de imersão das amostras. Entretanto, o acréscimo do CaCl2 ao CPB diminuiu...(Resumo completo, clicar acesso eletrônico abaixo)Abstract: The aim of this study was to evaluate the influence of adding 10% calcium chloride (CaCl2) on the setting time, solubility and dissolution, pH, and antimicrobial activity of white MTA (MTA) and Portland cement with radioopacifier (CPB). ProRoot MTA (PRO) with and without CaCl2 was also included in the antimicrobial activity test. Setting time testing followed the specification #57 of ADA and final setting time testing was made according to C266-03 ASTM standard. Six teflon rings (4 mm thickness, 12 mm internal diameter, 2 mm height) used for the solubility, dissolution, and pH tests were stored in deionized water for 24h, 72 h, 7d, 14d, and 28d, which was renewed at the end of each storage period. After the storage periods, the specimens were dehydrated in a desiccator containing silica gel for 24h. The specimens were weighted before and after dehydration and pH of water was measured using a pH-meter. Antimicrobial activity was evaluated using an Agar well diffusion technique. The following microorganisms were used: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Candida albicans, and Staphylococcus epidermidis (ATCC). Adding of CaCl2 yielded a 50% reduction of the initial setting of the cements. Final setting time of MTA cement was reduced approximately 35.5% and CPB's final setting time was reduced by 68.5%. Solubility results have shown that the MTA+ CaCl2 absorbed water and did not lost weight with time, except for the 24h-storage period. Hydrated and dehydrated MTA presented weight loss, but within acceptable limits stated by ADA. CPB presented greater solubility, proportional to the immersion time, i.e., the greater the storage period the greater the weight loss. However, adding CaCl2 to the CPB did not decrease the solubility. Both CPB and CPB+ CaCl2 did not satisfy ADA requirements. (Complete abstract, click electronic access below)
Orientador: Roberto Miranda Esberard
Coorientador: Clovis Monteiro Bramante
Banca: Marco Antônio Hungaro Duarte
Banca: Wilson Tadeu Felippe
Banca: Mario Tanomaru Filho
Banca: Idomeo Bonetti Filho
Doutor
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Pollock, Natashka S. "Chloride movement during calcium uptake into the sarcoplasmic reticulum of cardiac and smooth muscle". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq24693.pdf.
Testo completo
31
George, Laurie J. "Efficiencies of Mass Encapsulation in Alginate of Vegetative Explants". OpenSIUC, 2015. https://opensiuc.lib.siu.edu/dissertations/1105.
Testo completoAbstract (sommario):
‘Lord Baltimore’ hardy hibiscus (Hibiscus moscheutos L.) was used in the mass encapsulation protocol, rinsing effects on bulk encapsulation, growth comparisons using K-NAA, acclimatization to greenhouse environment, and leaf anatomy comparisons. Nodal segments, each containing a single axillary bud, were harvested and cut to 4mm prior to mass encapsulation. Results showed that using 2.75% alginate with a concentration of 60 or 80 mM calcium chloride produced an alginate mass, or “cookie”, which was able to hold together during rinsing protocols. The rinsing study resulted with the potential to reduce rinse times from 2 three-minute rinses to 1 one-minute rinse. After 4 weeks under mist, ~58% of root growth was generated when using 1 one-minute rinse. After 8 weeks under mist, the greatest percentage of shoot and root growth occurred when using 1 one-minute rinse. The use of K-NAA in the gel matrix, after four weeks, resulted in no discernable differences. Concentrations of 0 or 0.1 µM will generate a greater percentage of shoot and root growth. Using 1.0 µM K-NAA, and extending the time under mist to 8 weeks, will result in a greater percentage of shoots and roots generated. Acclimatization study investigated the survival rates on mass encapsulated nodal segments, looking at different media, depth of planting and humidity. Increases in shoot lengths can be expected up to 8 weeks under mist and planted either on top or 1 cm deep. A reduction in root growth was seen when placed on top of the medium after 4 weeks. The anatomical study found differences in the leaf cell lengths based on the stage of leaf development. However, there was no indication of a gradual change in anatomy as they adapted from in vitro to greenhouse environment. The best results were found when comparing epidermal, palisade and spongy mesophyll cells on the fourth fully expanded leaf under mist. Hydrangea quercifolia ‘Snow Queen’ was used to test the effects of tissue culture media and plant growth regulators. Research found that using dichloroisocyanuric acid (NaDCC) resulted in a decrease of contamination on explants without a reduction in the number of shoots produced. This would reduce the amount of time and labor on the encapsulation procedure, as no rinsing is required. The best result, looking a nutrient formulation, was found to be WPM with 1 µM BA added.
32
Zhan, Rijing. "Kinetic study of low temperature sulfur dioxide and hydrogen chloride removal using calcium-based sorbents". Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1181166008.
Testo completo
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Miesle, Terrence J. "The modification by calcium chloride of the firmness and pectic substances of highbush blueberry fruit". Connect to resource, 1991. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=osu1260552870.
Testo completo
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Al-Othman, Amani Lutfi. "Gypsum production and hydrochloric acid regeneration by reaction of calcium chloride solution with sulfuric acid". Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82463.
Testo completoAbstract (sommario):
One critical issue in chloride hydrometallurgy is the regeneration of the lixiviant HCl that is commonly achieved by pyrohydrolysis. It is the scope of this thesis to investigate a low temperature HCl regeneration process, which regenerates HCl and produces saleable gypsum. Experiments were performed to determine the optimum conditions of the chemical reaction that involved the reactive mixing of calcium chloride (CaCl2) solution with sulfuric acid (H2SO4) solution at low temperature and atmospheric pressure.The results showed that the crystallization chemistry of the CaCl 2-H2SO4 reaction can be controlled in such away that favors the production of well grown gypsum crystals with the simultaneous regeneration of practical strength HCl. High strength HCl (= 4 M) was regenerated by the reaction of (3.5 M) CaCl2 leach solutions with (8 M) sulfuric acid in the temperature range of 20-60°C. Acid addition in stages to simulate the titration procedure, seeding and recycling, and increasing temperature were found to favor crystal growth and filterability. Finally, this research showed that there is negligible metal uptake with the exception of lead, making the production of marketable gypsum possible.
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Rawahy, Salim Ali 1951. "EFFECT OF SODIUM-CHLORIDE, SODIUM-SULFATE AND CALCIUM-CHLORIDE SALTS ON NITROGEN AND PHOSPHORUS UPTAKE BY TOMATO PLANTS (SALINITY, OSMOTIC PRESSURE, SPECIFIC ION EFFECT)". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/275527.
Testo completo
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Gualco, Scott J. "Effect of sodium chloride addition during diafiltration on the solubility of milk protein concentrate". DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/427.
Testo completoAbstract (sommario):
There is considerable interest among food manufacturers to incorporate protein into food products in both developed and developing countries. Dairy proteins are excellent choices for many different applications, as they are known to have several nutritional and functional benefits. Membrane filtration techniques are often utilized as the preferred method of fractionation, due to the high throughput and continuous nature of the process. One such product produced from membrane filtration of skim milk is called milk protein concentrate. This product is valued for its high protein content, but it has historically exhibited poor solubility when reconstituted into water, which severely restricts the food applications for which it is suitable. There is some existing evidence that milk protein concentrates which contain elevated levels of sodium exhibit higher solubility upon reconstitution into water. The main objective of this thesis project was to demonstrate the effect of sodium chloride, added to diafiltration (DF) water utilized during the manufacturing process, on the solubility of milk protein concentrate.
It was observed that the addition of sodium chloride into diafiltration water at levels of 50 mM, 100 mM, and 150 mM had a beneficial effect on the solubility of milk protein concentrate across a variety of reconstitution conditions. For example, when milk protein concentrate was mixed for 1 h on a stage mixer at 23 °C ± 1 °C, a significant increase (p < 0.001) in mean solubility was observed when at least 50 mM NaCl had been incorporated into DF water. The incorporation of 50 mM NaCl into DF water significantly increased (p < 0.001) the mean solubility of milk protein concentrate from 59.81 % to between 64.34 % and 71.78 %. The addition of 100 mM NaCl significantly increased (p < 0.001) the solubility to between 88.80 % and 96.24 %, and the addition of 150 mM NaCl significantly increased (p = 0.005) the solubility to between 92.79 % and 100 %.
Minerals analysis of dry powders revealed a significant increase (p < 0.001) in levels of sodium. The addition of 50 mM NaCl into DF water was associated with a significant increase (p < 0.001) in powder Na content to between 2.48 mg/g and 7.44 mg/g. The addition of 100 mM NaCl into DF water was associated with a significant increase (p = 0.002) in powder Na content to between 5.80 mg /g and 10.75 mg/g, and the addition of 150 mM NaCl into DF water was associated with a significant increase (p = 0.001) in powder Na content to between 9.57 mg/g and 14.53 mg/g. A significant difference (p < 0.001) in magnesium level was also detected. Differences in calcium content were not found to be statistically significant (p = 0.016) at α = 0.01.
Preliminary observations of milk protein concentrate upon reconstitution were made using a confocal laser scanning microscopy method. This method showed evidence of possible differences in powder particle rehydration and affinity for lipid association between powder particles manufactured at different treatment levels. As the level of NaCl incorporated into DF water increased, particle structures upon rehydration appeared more porous, and the incidence of lipid material that was not associated with powder particles appeared to increase.
Overall, this study demonstrates the importance of sodium content in determining the solubility of milk protein concentrate.
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Marden, Torres Sandro. "The influence of chloride on the thaumasite form of sulfate attack in mortars containing calcium carbonate". Thesis, University of Sheffield, 2004. http://etheses.whiterose.ac.uk/6064/.
Testo completoAbstract (sommario):
Chlorides have been reported to be present in several field cases where thaumasite attack has occurred. However, no published systematic research dealing with the role of chloride in the thaumasite form of sulfate attack could be found in the literature. This research project has been designed through a comprehensive experimental programme to address this issue. This investigation studies the following: the formation of thaumasite in long-term exposure of carbonated systems to sulfate environment; whether or not the presence of chloride affects the thaumasite form of sulfate attack (TSA); the effect of long-term and short-term carbonation on the precipitation of thaumasite; the composition of thaumasite formed in chloride containing solutions; the chloride binding capacity of thaumasite-affected cement matrix; and the use of metakaolin to prevent TSA in carbonated mortar. Mortar samples were cast using siliceous sand and Portland cement replaced by different amounts (0,5 and 15%) of limestone filler, and by 10% metakaolin. Mortar cubes were subsequently stored in deionised water, magnesium sulfate solution, combined sulfate and sodium chloride solution and simulated seawater at 5°C and 20°C. Long-term specimens consisted of Portland cement mortars containing 15% limestone filler, which were exposed to atmospheric carbonation at 5 and 20°C for 5 years, were also immersed in these salt solutions at both temperatures. The mortar cubes were examined regularly every month, and the results of visual assessment recorded. The mineralogy of the deteriorated products was determined by x-ray diffraction (XRD), infrared spectroscopy (IRS). The pH of the solutions was also measured periodically. The composition of the thaumasite and the deteriorated cement matrix was assessed by means of the determination of the unit cell parameters of the crystal, by quantitative infrared spectroscopy (IRS); scanning electron microscopy (SEM); backscattered electron image (BEI) and chemical analyses by energy dispersive X-ray and quantitative x-ray microanalyses. The results indicate that the effect of chloride on sulfate attack is affected by temperature, because it affects the solubility of some minerals and increases the activity of carbonates. At 20°C, the presence of chlorides appears to mitigate sulfate attack by combining with the aluminates of the cement forming Friedel's salt. At this temperature, the main carbonate phases were calcite and aragonite, whereas thaumasite was predominant in all samples at 5°C, which caused damage that increased with increase in the chloride concentration in solution and the carbonate content, as evidenced by increased loss of mass and pH. Because of the demand for an alkaline environment, thaumasite did not precipitate within the long-term carbonated surface areas, but immediately underneath. The formation of thaumasite was not prevented in carbonated specimens after short-term. In the presence of chloride, thaumasite precipitated with lower lattice parameter c, indicative of a higher carbonate to sulfate ratio, and its composition shifted towards the thaumasite end-member of the solid- solution series. Thus, chloride does not seem to enter into thaumasite crystal structure. In addition, the chloride binding capacity of thaumasite-affected areas of the cement is reduced as the residual CSH phase both decalcifies and loses its silicon to give place to the deposition of thaumasite. The performance of metakaolin containing mortars in salt solutions was improved by the pozzolanic effect, but also by an increase in the chloride binding capacity, which reduced the deleterious effect of the chloride on the formation of thaumasite. However, metakaolin-containing samples in magnesium sulfate developed some signs of damage that were detected after 18 months. The interaction between chloride and other ionic species on thaumasite formation in the cement matrix is very complex, and can have some implications to the CaC03 threshold for durable concretes under TSA prone environments and also to the steel corrosion of concrete reinforcement.
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Marsey, Laura Louise. "Molecular and functional investigations of the calcium activated chloride channel in cystic fibrosis pancreatic duct cells". Thesis, University of East Anglia, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445193.
Testo completo
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Chisholm, Paul Norman. "Dry absorption of hydrogen chloride and sulfur dioxide by calcium-based sorbents from humidified flue gas /". Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
Testo completo
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Kobata, Robert Steven 1954. "AN AUTOMATED METHOD OF MEASURING ISOLATED MUSCLE CONTRACTION (VERAPAMIL, HALOTHANE, CALCIUM-CHLORIDE, MAGNESIUM SULFATE, GUINEA PIG)". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/277003.
Testo completo
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Gohmann, Andrew Kaden. "Calcium phosphate nucleation induced by electrochemical methods". Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1627572348324976.
Testo completo
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Nasir, Subriyer. "Membrane performance and build-up of solute during small scale reverse osmosis operation". Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/590.
Testo completoAbstract (sommario):
Reverse Osmosis (RO) is widely accepted as an alternative method to produce freshwater from different feed water sources. This technology competitively substitutes the thermal processes in the near future because of several advantages particularly in energy saving. The success of RO operation will, however, depends largely on the overall membrane performance. Deposit or build-up of solute is one of the main reasons for membrane operation failure. Build-up of solute or deposit which is known as fouling and scaling will decrease the permeate flux and increase the energy consumption in particular after prolonged operation of RO. The thesis presents the experimental results obtained in a small-scale RO system. The aim of this study is to investigate the effect of sodium chloride and calcium carbonate on the membrane performance and subsequent build-up of solute on the membrane surface. The experiments were carried out in a small-scale of RO (2 m3/day capacity) with spiral wound membrane using simulated feed water, secondary effluent, and groundwater samples. The parameters chosen for the experiments are applied pressure (1250-4750 kPa), and concentration of sodium chloride (l00-5000 mg/L) and calcium carbonate (50-100 mg/L).The results from feedwater runs indicated that initial sodium chloride and calcium carbonate in feed water and applied pressure affects the overall membrane performance. However, there is no significant effect on membrane performance for sodium chloride with concentration below 1200 mg/L and applied pressure lower than 2250 kPa. Applied pressure appears to have an impact on build-up of sodium and calcium on the membrane surface for pressures greater than 2750 kPa. For typical small-scale RO system used in this experiment, build-up of calcium will slightly decrease with given pressure caused by the characteristic of membrane that easily removes the divalent ions. The osmotic pressure of solution also strongly affects the permeate flow rate in particular for relatively higher sodium concentration (> 2500 mg/L). As a consequence of higher osmotic pressure, zero permeate flux is achieved when sodium chloride concentration was greater than 5000 mg/L and applied pressure lower than 1750 kPa. Results also indicated that fouling might pose a potential problem in small-scale RO operation. In order to investigate the membrane performance, experiments with secondary effluent samples were also performed. Results indicated that water recovery percentages and permeate flux also linearly increase with applied pressure. However, effectiveness of membrane decreases less than 98% otherwise build-up of solute tends to increase. It is suggested that lower values of the water recovery percentage (WRP) and permeate flux (Jw) are caused by the characteristic of secondary effluent that have high-suspended solids, organic carbon, and minerals. Further, the membrane performance also examined with ground water as feed water sample.Results showed that both water recovery percentage and permeate flux linearly increased with operating pressure. However, intensive pretreatment are required as a result of higher concentration of humic acid and iron in raw feed. Percentages of ion rejection for sodium and calcium are greater than 98 and 99% respectively. The high ion rejections are mainly due to the characteristics of groundwater with low TDS and EC. Sodium and calcium build-up in a small-scale RO system considered appears to be affected by the applied pressure. Build-up of solute in small-scale of RO system has been predicted using the empirical model proposed in this work. Two ions namely sodium and calcium in feed water considered as predominant ions responsible for fouling and scaling on the membrane surface. Four main parameters namely, applied pressure (P), permeate flux (Jw), membrane resistance (Rm), and feed concentration (Cf) are considered which strongly affect the overall membrane performance. The empirical correlations derived from experimental observation among these parameters can be expressed as follows: In Md NaCI = O. 77 In P + 0.67 In Jw + 0.19 In Rm + 0.171n Cf In Md CaCO3= 0.96 In P + 0.75 In Jw + 0.2 In Rm - 0.07 In CfThe empirical models proposed in this thesis may be useful for predicting the buildup of solute on the membrane surfaces. In the present work, an attempt has been made to estimate the energy consumption and unit cost for desalting of different feed water samples in a small-scale RO system. In RO plants, unit cost of water production from feed water is primarily governed by the energy required for pumping raw water. Estimates of specific energy consumption (SEC) for desalting of sodium chloride, combined sodium and calcium carbonate solutions were found to be in the range of 0.79 - 3.21 and 0.81 - 3.22 kwh/m3 respectively. For groundwater and secondary effluent, they are estimated to 0.63 - 1.71 and 0.79 - 2.02 kWh/m3 respectively. Moreover, energy consumption for different feed water samples was used to estimate the unit cost for water production. Estimation of unit costs for combined sodium chloride and calcium carbonate solution, groundwater, and secondary effluent runs are $2.06 - 3.22, $1.98 - 2.57 and $1.56- 2.66 respectively. In this work, unit cost is still higher due to greater energy consumption .by the pumping system which is required in a small-scale RO operation. Based on the experimental results, it appears that the characteristics of feed water samples affect the membrane performance and their effects must be taken into account in the design of RO units so as to reduce the unit cost for water production.The findings from the present experimental and modelling work are of practical significance in not only providing the knowledge base in the area of desalination but also paves the way for developing tools for the prediction of build-up of solutes on membrane surface in full scale reverse osmosis operations.
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O'Driscoll, Kate E. "Molecular and functional expression of the murine Bestrophin family from cardiovascular tissues". abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3289453.
Testo completo
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Zhu, Fenfen. "Technological Development of an Effective Recycling System for Fly Ash from Municipal Solid Waste Incinerator to be Raw Material in Cement Industry". 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/66206.
Testo completoAbstract (sommario):
Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第14148号
工博第2982号
新制||工||1443(附属図書館)
26454
UT51-2008-N465
京都大学大学院工学研究科都市環境工学専攻
(主査)教授 津野 洋, 教授 森澤 眞輔, 教授 酒井 伸一
学位規則第4条第1項該当
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Brookfield, Rebecca. "The pharmacology and cardiovascular function of TMEM16A channels". Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/the-pharmacology-and-cardiovascular-function-of-tmem16a-channels(bdc16466-cecd-4343-9d40-b20bc647d70f).html.
Testo completoAbstract (sommario):
Calcium-activated chloride channels (CaCCs) are ubiquitously expressed in a plethora of cell types and, consequently, are involved in numerous cellular processes as diverse as epithelial secretion, regulation of cardiac excitability and smooth muscle contraction. Current pharmacology of CaCCs is limited to compounds with low potency and poor selectivity. The lack of knowledge surrounding the molecular identity of the CaCC has greatly hindered the development of more specific drugs and has impaired our understanding of the channel physiology and biophysics. The recent discovery that the TMEM16A gene codes for CaCCs has offered hope for new developments in these areas. CaCCs have been suggested as possible targets to treat a variety of conditions including asthma as well as pulmonary and systemic hypertension. Due to the ubiquitous expression of CaCCs and the ability of the channel to interact with a number of pharmacological compounds with diverse chemical structures however, it was hypothesised that TMEM16A could be a possible source for off-target drug effects and may represent a concern for safety pharmacology. The principal aim of this thesis was to assess the functional significance of TMEM16A in the cardiovascular system, as this is one of the major systems of concern for safety pharmacology and accounts for the largest number of post-market drug withdrawals. The main findings of this study can be summarised as follows: 1) RT-PCR analysis revealed a ubiquitous expression of TMEM16A in tissues of the rat and human cardiovascular systems, including systemic and pulmonary arteries as well as cardiac tissue. Analysis also revealed the presence of multiple TMEM16A splice variants in all rat tissues examined, in addition to a number of other TMEM16x family members. 2) Myography experiments using the “classical” CaCC blocker niflumic acid and newly identified TMEM16A blockers confirmed a functional role for TMEM16A in phenylephrine-induced vascular smooth muscle contraction. 3) The suitability of currently available Cl- channel blockers for use as pharmacological tools for TMEM16A research was assessed using conventional whole-cell patch clamp and high-throughput electrophysiology techniques to respectively compare their potencies and selectivity over other cardiovascular ion channels. Of the compounds tested, DIDS and T16Ainh-A01 appeared the most suitable blockers; however all compounds had a degree of non-selectivity, raising concerns for their use in functional studies. In conclusion, these findings provide evidence for the ubiquitous expression and functional significance of TMEM16A within the cardiovascular system and support the hypothesis that TMEM16A is a concern for safety pharmacology and should be included into future pre-clinical safety assays. The inadequacy of current inhibitors however highlights the urgency for the development of novel potent and selective channel modulators for future TMEM16A research.
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Horita, Claudia Nakamura 1972. "Redução de sódio em salsichas com alto teor de carne de frango mecanicamente separada = efeito de sais substitutos e derivados de alho sobre atributos de qualidade e segurança". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255101.
Testo completoAbstract (sommario):
Orientador: Marise Aparecida Rodrigues PollonioTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A redução do consumo de sódio tem sido recomendado por vários órgãos da saúde em função da correlação positiva entre ingestão de sódio e o desenvolvimento de doenças como a hipertensão arterial, cardiovasculares e renais. Produtos cárneos emulsionados cozidos, principalmente salsichas, estão entre os mais consumidos no Brasil e apresentam elevados teores de sódio. Em algumas categorias de salsichas, matérias-primas menos nobres são adicionadas para reduzir o custo, dentre elas a carne mecanicamente separada de aves (CMS) permitidas em concentrações de até 60%. Cloreto de sódio é um ingrediente multifuncional, pois confere propriedades sensoriais, conservantes e tecnológicas em produtos cárneos. Adicionalmente, em formulações contendo alto teor de CMS sua redução pode ser ainda mais desafiadora pela perda de propriedades funcionais da matriz cárnea (presença de proteínas de menor funcionalidade, porções da medula óssea, alto teor de colágeno e gordura). Desta forma, este trabalho teve como objetivos estudar a influência da redução de sódio na qualidade de salsichas com alto teor de CMS. O trabalho foi dividido em três etapas. Na primeira etapa, blends de cloreto de potássio e cálcio, com força iônica equivalente a 2% NaCl, foram utilizados para substituir 25% ou 50% do NaCl em salsichas contendo 60% de CMS. O objetivo desta etapa foi avaliar o efeito da adição dos blends de sais sobre as propriedades físico-químicas e sensoriais das salsichas. Foram determinados: teor de sódio, Aw, estabilidade de emulsão (batter), avaliação de cor instrumental, perfil de textura, microestrutura e teste de aceitação sensorial. Na segunda etapa, uma formulação contendo blend de sais para substituir 50% NaCl foi selecionada com base nos dados da primeira etapa.e adicionada de derivados de alho (fresco, em pó, óleo comercial e extrato obtido via líquido pressurizado). O objetivo foi investigar os efeitos dos derivados de alho como antioxidantes e antimicrobianos nas formulações de salsichas. As determinações realizadas foram a mesmas da primeira etapa, com exceção da microestrutura e acrescidas da quantificação de Substâncias Reativas ao Ácido Tiobarbitúrico e análises microbiológicas durante 60 dias sob refrigeração. Finalmente, para as mesmas formulações de salsichas, uma terceira etapa foi realizada para avaliar o efeito dos derivados de alho como realçadores de sabor por meio da Análise Descritiva Quantitativa e Teste de Aceitação, utilizando-se duas amostras comerciais para efeito comparativo. Alho fresco e extrato de alho PLE, nas concentrações de 1% e 0,02% respectivamente, apresentaram propriedades antioxidantes e antimicrobianas durante a vida útil das salsichas. Dezoito descritores caracterizaram as amostras das salsichas avaliadas pelos assessores na análise descritiva quantitativa. De forma geral, os tratamentos do estudo apresentaram maior intensidade de sabor e aroma de alho e as amostras comerciais apresentaram aroma e sabor defumado. No teste de preferência, as salsichas comerciais foram as mais aceitas para impressão global, no entanto, salsichas elaboradas para o estudo apresentaram muitas similiaridades entre si em seus perfis sensoriais. Assim, a adição de derivados de alho em salsichas com alto teor de carne mecanicamente separada e adicionada de blends de sais substitutos de NaCl mostraram ser uma alternativa promissora neste seguimento
Abstract: The positive correlation between salt intake and the development of diseases including hypertension, and cardiovascular and renal disorders has led health authorities to recommend the reduction of sodium intake. Cooked emulsified meat products, mainly sausages, have high sodium levels and are among the most consumed products in Brazil. In some types of sausages, the mechanically deboned poultry meat (MDPM) stands out as less noble materials used to reduce costs, allowed in concentrations of up to 60%. Sodium chloride is a multi-functional ingredient, since it provides sensory, preservative, and technological properties in meat products. Sodium reduction can be even more challenging in formulations containing high MDPM levels, due to loss of functional properties of the meat matrix (presence of proteins of lower functionality, portions of the bone marrow, high collagen and fat contents). Thus, this study aimed to investigate the effect of sodium reduction on the quality of sausages with high MDPM content. The study was divided into three stages. In the first step, blends of potassium chloride and calcium chloride with ionic strength equivalent to 2% NaCl were used to replace 25% or 50% of NaCl in sausages containing 60% MDPM. The purpose of this step was to evaluate the effect of the addition of salt blends on the physicochemical and sensory characteristics of the sausages. The following parameters were investigated: sodium content, Aw, emulsion stability (batter), instrumental color, texture profile, microstructure, and sensory acceptance. In the second step, a formulation containing a salt blend to replace 50% NaCl was selected from the first step, and garlic derivatives (fresh, powder, commercial oil, extract obtained by pressurized liquid extraction) were added. The objective was to investigate the effects of garlic derivatives as antioxidant and antimicrobial agents in the sausage formulations. The determinations were the same as the first step, except for microstructure, plus measurement of Thiobarbituric Acid Reactive Substances and microbiological analyses during 60 days of refrigerated storage. Finally, a third step was carried out to evaluate the effect of garlic derivatives as flavor enhancers through quantitative descriptive analysis and acceptance tests, using two commercial samples for comparison. Fresh garlic and garlic PLE extract at concentrations of 1% and 0.02%, respectively, presented antioxidant and antimicrobial properties throughout the shelf life of the sausages. The sausage samples were characterized by eighteen descriptors selected by the assessors in the quantitative descriptive analysis. In general, the treatments had higher flavor intensity and garlic flavor, while the commercial samples exhibited smoky aroma and flavor. In the preference test, the commercial sausages were the most accepted for overall impression, and the sausages prepared for the study presented very similar sensory profiles. Thus, the addition of garlic derivatives in sausage formulations containing high mechanically separated poultry and blends of salt substitutes proved to be a promising alternative in this field
Doutorado
Tecnologia de Alimentos
Doutora em Tecnologia de Alimentos
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Kannan, Sarath. "Experimental Investigation of Lithium Nitrate Trihydrate and Calcium Chloride Hexahydrate as Salt Hydrate PCMs for Thermal Energy Storage". University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563273912013393.
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Sagheddu, Claudia. "Functional characterization of molecular candidates for the calcium-activated chloride channels in the cilia of olfactory sensory neurons". Doctoral thesis, SISSA, 2010. http://hdl.handle.net/20.500.11767/4147.
Testo completoAbstract (sommario):
Olfactory sensory neurons (OSNs) use a Ca2+-activated Clˉ channels amplification mechanism in olfactory transduction. Odor binding to odorant receptors in the cilia of OSNs leads to an increase of intraciliary Ca2+ concentration by Ca2+ entry through cyclic nucleotide-gated channels. Ca2+ activates a Clˉ channel that leads to an efflux of Clˉ from the cilia, contributing to the depolarization in OSNs. The molecular identity of the olfactory Ca2+-activated Clˉ channel is not definitely established. Bestrophin2 and TMEM16b/anoctamin2 are located at the surface of the olfactory epithelium, in the cilia of OSNs where olfactory transduction takes place.
Moreover when expressed in heterologous systems each of these proteins produces Ca2+-activated Clˉ currents. Both proteins have been indicated as a candidate for being a molecular component of the olfactory Ca2+-activated Clˉ channel. In the first part of this Thesis we analyzed knockout (KO) mice for bestrophin2. We compared the electrophysiological properties of Ca2+-activated Clˉ currents in OSNs from WT and KO mice for bestrophin2. Our data show that Ca2+-activated Clˉ currents are still present in the cilia of OSNs from KO mice for bestrophin2 and that their properties are not significantly different from those of WT mice. These results indicate that bestrophin2 does not appear to be the main molecular component of the olfactory Ca2+-activated Clˉ channel. Therefore further studies are required to determine the physiological function of the bestrophin2 in the cilia of OSNs.
In the second part of this Thesis we measured functional properties of the native Ca2+- activated Clˉ current in mouse OSNs and compared them with those of TMEM16b/anoctamin2-induced current in transfected HEK cells. We found a similar extracellular blocking potency for some Clˉ channels blockers, a similar anion permeability sequence and a reversal potential time-dependency. Therefore, we conclude that the measured electrophysiological properties are largely similar and further indicate that TMEM16b/anoctamin2 is likely to be a major subunit of the
native olfactory Ca2+-activated Clˉ current.
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Chalamuri, Shanmuka Harish. "The Evaluation of the Effect of Anionic and Cationic Surfactants on the Hindered Settling of Light Calcium Carbonate Suspensions". University of Toledo Health Science Campus / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=mco1418602604.
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Lima, Maria Aparecida [UNESP]. "Conservação pós-colheita de goiaba pelo uso de reguladores de crescimento vegetal, cálcio e da associação destes com refrigeração e embalagens plásticas". Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/105293.
Testo completoAbstract (sommario):
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lima_ma_dr_jabo.pdf: 538530 bytes, checksum: 2342b94d3c4158a909a0895facf7c72a (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Avaliou-se os efeitos da aplicação de giberelina, citocinina, auxina, cloreto de cálcio e 1-metilciclopropeno, assim como de embalagens e refrigeração na conservação pós-colheita de goiabas 'Paluma' e 'Pedro Sato'. As aplicações foram feitas utilizando-se uma solução de manitol a 300mM como veículo e utilizando-se infiltração a vácuo (500 mmHg por 20 minutos). No 1º experimento os frutos tratados com os reguladores e com o cálcio foram armazenados a 21,6ºC, 73,4% UR. Os tratamentos com cloreto de cálcio a 1% ou 2% propiciaram uma vida de prateleira de 7 dias às goiabas 'Paluma' ou seja, aumentou-lhes esta vida em um dia. As goiabas 'Pedro Sato', tratadas com CaCl2 a 2%, ácido indolacético (IAA) e ácido giberélico (GA) a 100 mg.L-1 apresentaram vida útil de 8 dias, ou seja, aumentada em 2 dias. No 2º experimento testou-se a combinação do CaCl2 a 2% com GA ou com IAA, a 200 mg.mL-1, e também a combinação destes três produtos (CaCl2xGAxIAA). Os frutos da 'Paluma' e da 'Pedro Sato' foram armazenados a 24,90C e 78,5%UR e a 23,80C e 69,0%UR, respectivamente. A associação entre CaCl2xGAxIAA foi a melhor na conservação pós-colheita destes frutos, assim como a CaCl2xIAA para as 'Paluma' e a CaCl2xGA para as 'Pedro Sato', pois levaram a menor perda de massa fresca, mantiveram a aparência e propiciaram-lhes aumento de dois dias na vida útil. No 3º experimento, os frutos destas duas cultivares foram submetidos aos tratamentos: Testemunha (sem tratamento); CaCl2 a 2% e ácido giberélico a 200 mg.L-1 e em seguida embalados em bandejas de polietileno tereftalatado (PET), revestidas com filme de polietileno de baixa densidade tendo 5% da área perfurada, celofane ou cloreto de polivinila (PVC) , antes do armazenamento a 10°C e 94ºC... .
The effects of gibberellin, cytokinin, auxin, calcium chloride and 1-methylcyclopropene as well as packaging and cooling on postharvest conservation of guavas 'Paluma' and 'Pedro Sato' were evaluated. The applications were done using a 300 mM mannitol solution as carrier and vacuum infiltration (500 mm Hg for 20 minutes). In the first experiment fruits were treated with growth regulators and calcium and stored at 21.6ºC, 73.4% RH, treatments with calcium chloride at 1% or 2% yielded a 7-day shelf life for 'Paluma' guavas, that is, increased its shelf life for one day. 'Pedro Sato' guavas, treated with CaCl2 at 2%, indole-acetic acid (IAA) and gibberellic acid (GA) at 100 mg.L-1 yielded an 8-day shelf life, that is, an increase of 2 days. In the 2nd experiment a combination of do CaCl2 a 2% with GA or with IAA, at 200 mg.mL-1 and also a combination of these three products (CaCl2xGAxIAA) was evaluated. 'Paluma' and 'Pedro Sato' fruits were stored at 24.9ºC and 78.5% RH and at 23.80C and 69.0% RH. The association of CaCl2xGAxIAA was the best for post harvest conservation of these fruits, as well as CaCl2xIAA for 'Paluma' guavas and CaCl2xGA for 'Pedro Sato', since they lead to smaller loss of fresh weight, maintained fruit appearance and increase shelf life by two days. In the 3rd experiment guava fruits of these two cultivars were subjected to the treatments: control (no treatment); CaCl2 at 2% and gibberellic acid at 200 mg.L-1 and were subsequently packaged in polyethylene tereftalatado (PET) trays, covered by a low density polyethylene with 5% of its area perforated, cellophane or polyvinyl chloride (PVC), before storage at 10°C. Calcium and gibberellic acid did not have an affect on fruit ripening, but PVC film was more efficient on fruit conservation than cellophane, which was better than the perforated polyethylene... (Complete abstract, click eletronic address below).