Дисертації: "Physicochemical and biological properties"

1

Knaggs, Roger D. "Physicochemical properties of opiates : analytical and biological relevance." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363687.

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Ochoa, Rodríguez Victor Manuel. "Physicochemical and biological properties of Biodentine associated with radiopacifiers /." Araraquara, 2018. http://hdl.handle.net/11449/153853.

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Orientador: Gisele Faria
Resumo: BiodentineTM (BD) apresenta bioatividade, biocompatibilidade e propriedades físico-químicas adequadas; no entanto, não possui radiopacidade adequada. Os objetivos foram avaliar (1) a radiopacidade de BD e BD associado com 15% de tungstato de cálcio (BDCaWO4) ou óxido de zircônio (BDZrO2), empregando sistemas de radiografia convencional e digital; e (2) as propriedades físico-químicas de tempo de presa, pH e solubilidade, e as propriedades biológicas de citocompatibilidade e potencial para induzir mineralização desses cimentos. Para a avaliação da radiopacidade, cada corpo de prova foi radiografado ao lado de uma escada de alumínio usando filme oclusal, placa de fósforo ou sensores digitais. As radiografias convencionais foram digitalizadas por câmera fotográfica ou scanner. Os valores médios de cinza dos materiais foram expressos em milímetros de alumínio (mm Al). A solubilidade foi avaliada após 7 dias de imersão dos espécimes em água destilada e expressa em percentagem de perda de massa. O tempo de presa foi avaliado empregando a agulha de Gillmore (105 ± 0,5 g) e o pH foi mensurado com um medidor de pH. A citocompatibilidade e a bioatividade celular foram avaliadas em células de linhagem osteoblástica (Saos-2) utilizando os ensaios de metiltetrazólio (MTT), vermelho neutro (NR), atividade de fosfatase alcalina (ALP) e coloração de vermelho de alizarina. Os dados foram avaliados utilizando ANOVA de um fator e pós-teste Tukey ou ANOVA de dois fatores e pós-teste de Bonferron... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: BiodentineTM (BD) presents bioactivity, biocompatibility and suitable physicochemical properties; however, it does not have adequate radiopacity. The objectives were to evaluate (1) the radiopacity of BD and BD associated with 15% calcium tungstate (BDCaWO4) or zirconium oxide (BDZrO2), employing conventional and digital radiography systems; and (2) the physicochemical properties of setting time, pH and solubility, and biological properties of cytocompatibility and potential to induce mineralization of these cements. For radiopacity evaluation, each cement specimen was radiographed alongside an aluminum step-wedge using occlusal film, photostimulable phosphor plates or digital sensors. The conventional radiographies were digitized by digital photographic camera or scanner. Mean grey values of materials were expressed in millimeters of aluminum (mm Al). Solubility was evaluated after 7 days of specimens’ immersion in distilled water and expressed as percentage of mass loss. Setting time was evaluated employing a Gillmore needle (105 ± 0.5 g) and pH was evaluated with pH meter. The cytocompatibility and cell bioactivity were evaluated in osteoblasts-like cells (Saos-2) using methyl-thiazol-tetrazolium (MTT), neutral red (NR), alkaline phosphatase (ALP) activity and alizarin red staining assays. The data were evaluated using one-way ANOVA and Tukey post-test or two-way ANOVA and Bonferroni post-test (α=0.05). BD radiopacity was below 3 mm Al and BDZrO2 and BDCaWO4 was above 3 mm... (Complete abstract click electronic access below)
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Kavatzikidou, Paraskevi. "Ceramics and metals processed by selective laser melting (SLM) : biological and physicochemical properties." Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479033.

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4

Queiroz, Marcela Borsatto. "Physicochemical and biological properties of tricalcium silicate-based reparative materials with alternative radiopacifiers and Biosilicate /." Araraquara, 2018. http://hdl.handle.net/11449/153908.

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Orientador: Mário Tanomaru Filho
Abstract: Tricalcium silicate cements associated with radiopacifiers are used as repair materials. Publication 1: Evaluation of tricalcium silicate-based cements (TCS) associated with zirconium oxide (ZrO2), calcium tungstate (CaWO4) or niobium oxide (Nb2O5) radiopacifiers compared to MTA Repair HP (MTA HP). Publication 2: Evaluation of tricalcium silicate-based cements (TCS) associated with zirconium oxide (ZrO2) radiopacifier with 10% or 20% of Biosilicate (TCS ZrO2 + 10% Biosilicate and TCS ZrO2 + 20% Biosilicate) compared to Biodentine. Setting Time (ST) and radiopacity were evaluated based on ISO 6876/2002 standard. Solubility was evaluated according to the method proposed by Carvalho-Júnior et al. (2007) modified. pH was measured at 3, 12 and 24 hours and 7, 14 and 21 days after immersion in distilled water. Cellular cytotoxicity and bioactivity were evaluated by methyltetrazolium (MTT), neutral red (NR), alkaline phosphatase (ALP), alizarin red (ARS) and real time PCR (qPCR) (Publication 1) assays in different periods of contact with eluates of the materials in Saos-2 cells. Antibacterial activity was evaluated by direct contact on Enterococcus faecalis in the planktonic form. For the physico-chemical and ARS tests, the data were submitted to ANOVA and Tukey tests; for MTT, NR and ALP tests the data were analyzed by the Two-Way ANOVA and Bonferroni tests; the antibacterial activity, were submitted to Kruskall-Wallis and Dunn tests (α = 0.05). Publication 1: TCS + CaWO4 presented... (Complete abstract click electronic access below)
Resumo: Cimentos de silicato tricálcico com radiopacificadores são utilizados como materiais reparadores. Publicação 1: Avaliação de cimento à base de silicato tricálcico (STC) associado aos radiopacificadores óxido de zircônio (ZrO2), tungstato de cálcio (CaWO4) ou óxido de nióbio (Nb2O5) em comparação ao MTA Repair HP (MTA HP). Publicação 2: Avaliação de material à base de silicato tricálcico (STC) e radiopacificador óxido de zircônio (ZrO2) e 10% ou 20% de Biosilicato (STC ZrO2 + 10% de Biosilicato e STC ZrO2 + 20% de Biosilicato) em comparação ao Biodentine. Tempo de presa e a radiopacidade foram avaliados seguindo ISO 6876/2002. A solubilidade foi avaliada de acordo com o método proposto por Carvalho-Júnior et al. (2007) modificado. pH foi avaliado 3, 12 e 24 horas, 7, 14 e 21 dias após imersão em água destilada. A citotoxidade e bioatividade celular foram avaliadas pelos testes metiltetrazólio (MTT), vermelho neutro (VN), atividade de fosfatase alcalina (ALP), ensaio de vermelho de alizarina (ARS) e PCR em tempo real (qPCR) (Publicação1), em diferentes períodos de contato com eluídos dos materiais em células Saos-2. Atividade antimicrobiana dos materiais foi avaliada por meio do teste de contato direto com Enterococcus faecalis na forma planctônica. Para os testes físicoquímicos e ARS, os dados foram submetidos aos testes ANOVA e Tukey; para os ensaios do MTT, VN e ALP e qPCR os dados foram analisados aos testes Two Way ANOVA e Bonferroni; os dados da atividade antimicrobiana f... (Resumo completo, clicar acesso eletrônico abaixo)
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5

Wilds, Christopher James. "Synthesis, physicochemical and biological properties of oligonucleotides containing 2-fluoro-2-deoxy-℗-D-arabinose." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36730.

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Oligonucleotides containing the modification 2-fluoro-2-deoxy-beta-D-arabinose (2'F-ANA) were synthesized via solid phase synthesis in order to investigate their ability to bind to nucleic acids (DNA and RNA). The ability of this modification to serve as a suitable antisense oligonucleotide construct was also evaluated.
All four nucleobase monomers (thymine, cytosine, adenine and guanine) were prepared for solid phase oligonucleotide synthesis, from which homopolymeric and heteropolymeric base sequences were assembled. These molecules bound with very good affinities to both DNA and RNA targets. Structural studies via NMR experiments demonstrated that in a 2'F-ANA/RNA duplex the 2'F-ANA residues adopt an O4' -endo conformation, similar to what has been proposed for the structure of DNA in a DNA/RNA hybrid.
A 2'F-ANA oligopyrimidylate formed a triple-helical complex with duplex DNA and hybrid DNA(Pu):RNA(Py) with an affinity higher than that of a corresponding DNA strand. Also, a cytosine-rich 2' F-ANA strand was found to form a complex at acidic pH which has properties similar to that of i-motif DNA.
Finally, 2'F-ANA strands when hybridized to RNA were found to activate RNase H, an enzyme that is involved in the mechanism of action of antisense drugs. 2'F-ANA is the first example of an antisense analogue that demonstrates improved binding to RNA relative to DNA and still retains the ability to elicit RNase H activity.

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6

Hellmuth, Isabell [Verfasser]. "Functionally modified (Deoxy)Ribonucleotides : synthesis and study of physicochemical and biological properties / Isabell Hellmuth." Mainz : Universitätsbibliothek Mainz, 2017. http://d-nb.info/1132364590/34.

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7

Pinzon-Arango, Paola A. "Investigation of the Biological and Physicochemical Properties of Bacillus anthracis Spores during Germination, Virulence, and Killing." Digital WPI, 2012. https://digitalcommons.wpi.edu/etd-dissertations/21.

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Bacillus anthracis has been classified as one of the most dangerous bioterrorism agents causing high mortality rates in short periods of time. Anthrax spores are extremely resistant to chemical and environmental factors, and have the ability to return into a vegetative (virulent) state during the process of germination. Previous research has suggested that spores can be eradicated with common disinfectants after germination and release of spore coats. During germination, the spore coat is degraded, making the spore susceptible to penetration of chemicals into the spore core. While previous research has focused on a qualitative understanding of germination of spores by obtaining high-resolutions images of spore coats to understand how protein coat layers change during germination, very few studies have evaluated changes in mechanical properties of spores during germination, and how germination affects virulence of macrophages. In this study, we performed a series of in vitro experiments to do an in-depth analysis of germination and virulence of B. anthracis. Atomic force microscopy (AFM) was used to investigate changes in spore surface properties during germination including morphology, roughness, elasticity, and spring constant. AFM results suggested that germination mechanisms depend on germinants used to trigger germination and roughness of Bacillus species increase during germination. In addition, the elasticity and spring cell constant of B. anthracis spores are affected during germination since the elastic moduli and cell spring constant values decreased with time as the spore was germinating, making the cells more susceptible. Spore killing was also tested both in sporulated and vegetative B. anthracis using the antimicrobial peptide chrysophsin-3 and the surfactant dodecylamine (DDA). Both killing agents were capable of eradicating B. anthracis spores, but more killing was observed for spores that were germinating or had become vegetative. The presence of germinant receptors from the Ger operon and its role on germination kinetics of B. anthracis was also investigated. The germination of mutant spores that carried one receptor or lacked all germinant receptors was compared to the germination kinetics of wild-type B. anthracis. Our results suggest that germination of spores is modified by the presence or absence of germinant receptors. Furthermore, the mutant B. anthracis strain lacking all receptors germinated suggesting that other receptor independent pathways may exist in B. anthracis. Finally the ability of B. anthracis to adhere, grow, and invade macrophages was investigated. Invasion of macrophages by B. anthracis was dependent on germinant receptors and the ability of spores to germinate and multiply. Our results suggest that macrophages were not capable of killing infecting spores, and on the contrary, germination of spores inside macrophages caused the lysis of macrophages. An uncontrolled release of cytokines by macrophages was elicited by spores and germinated B. anthracis. Our study helps understand the process of germination of B. anthracis spores at a nanomolecular level. Our investigation may be a valuable tool in the design and development of antisporal compounds.

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8

Ruiz, Hernando María. "Effect of ultrasound, low-temperature thermal and alkali treatments on physicochemical and biological properties of waste activated sludge." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/301434.

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The development of treatment processes to reduce or reuse sewage sludge is crucial for a proper environmental management. Segregating primary from secondary sludge allows for better reuse of secondary sludge, since digested secondary sludge is better suited for agricultural application, containing about double concentration in nutrients but significantly less contaminants. However, secondary sludge (also called waste activated sludge (WAS)) is difficult to dewater compared with primary sludge due to the existence of colloidal materials and extracellular polymeric substances (EPSs), which strongly retain water. WAS is also more difficult to digest under anaerobic conditions due to the presence of glycan strands in microbial cell walls. The low dewaterability and digestibility of WAS can be improved by applying treatments, which can partially disintegrate the WAS by disrupting flocs and cells and solubilising the EPSs. The treatments studied in this thesis were ultrasound, low-temperature thermal and alkali with NaOH. Specifically, it has been analysed the effect of the aforementioned treatment on WAS rheology, dewatering, hygienisation and anaerobic digestion. Rheology is the study of stress-strain relationships of viscoelastic materials. All the sludges analysed (untreated and treated) behaved as non-Newtonian pseudoplastic fluids, which indicates that the viscosity decreases with the applied shear rate. The sludges were also thixotropic (showing a hysteresis area in the plot of stress versus shear rate), which means that the viscosity is time dependent. The three aforementioned treatments resulted in the reduction of the steady state viscosity and the hysteresis area. Complementarily, a rheological structural model was proposed to examine the variations in the thixotropic behaviour of WAS after the application of the treatments. Sludge dewatering is essential to obtain a product dry enough to allow a reduction in storage volume. The three conditions of the thermal treatment (60, 80 and 90 ºC; 1 h, including the heating time to reach the temperature) and the higher intensities of ultrasound (27,000 kJ/kg TS) and alkali (157 g NaOH/kg TS) treatments improved sludge dewatering by centrifugation. To further evaluate the effect of treatments on the sludge dewatering, the EPSs contained in sludge were extracted and characterised. The EPSs were fractionated to generate two different EPS fractions: loosely bound EPSs (LB-EPSs) and tightly bound EPSs (TB-EPSs), where the latter is the innermost fraction and harder to release. An analysis of the untreated sludge revealed that the proteins, followed by the humic acids and polysaccharides, were the major constituents of the EPSs. Each of these components was primarily observed in the TB-EPS fraction. The treatments, particularly the alkali treatment, thoroughly solubilised the EPS, as indicated by the increase in the TOC, protein, humic acid and polysaccharide contents in the LB-EPS fraction. As a result, the dewaterability of WAS was improved. Hygienisation of the sludge is of uttermost importance if the sludge is intended for agriculture. The level of hygienisation was evaluated using three indicator organisms: Escherichia coli, somatic coliphages (SOMCPH) and spores of sulfite-reducing clostridia (SSRC). The thermal treatment at 80 ºC and the alkali treatment at 157 g NaOH kg TS allowed the hygienisation of the sludge, thus satisfying normal levels accepted by the EPA and the 3rd official draft from the EU. Conversely, the conditions tested for the ultrasound treatment barely reduced the levels of microbial indicators. Mesophilic anaerobic digestion is a widely used method to stabilise the sludge. The alkali pre-treatment (157 g NaOH/kg TS) exhibited the greatest methane production increase (34%) followed by the ultrasonication (27,000 kJ/kg TS; 13%), whereas the thermal pre-treatment (80 ºC, 15 min) presented a methane potential similar to the untreated sludge. However, the use of NaOH as a pre-treatment is rather limited because of the rising sodium concentration in the digester.
El desarrollo de procesos para la reducción o reutilización de los lodos resulta determinante para una apropiada gestión medioambiental. Tratando por separado el lodo activado del primario (y no la mezcla como suele hacerse) se favorece el uso del lodo activado en agricultura tras su digestión, ya que el lodo activado contiene el doble de nutrientes y menor carga contaminante que el primario. No obstante, el lodo activado (también denominado lodo secundario o biológico) es más difícil de deshidratar que el primario, ya que presenta una estructura interna organizada de flóculos unidos por las sustancias poliméricas extracelulares (EPSs, por sus siglas en inglés), las cuales atrapan el agua. En este contexto, la reología, que es la ciencia que estudia las relaciones entre la fuerza y la deformación de los materiales, es una herramienta muy útil para la caracterización de la viscosidad o estructura interna de los lodos. El lodo activado es también más difícil de digerir anaeróbicamente debido a las cadenas de glicanos presentes en las paredes celulares de las bacterias. En resumen, para poder deshidratar y digerir un lodo activado será necesario acondicionarlo previamente mediante tratamientos, con el fin de solubilizar las EPSs y aumentar su biodegradabilidad. Si además el lodo quiere destinarse a agricultura deberá estar higienizado. En esta tesis se ha estudiado el efecto de tres tratamientos (ultrasonido, térmico a baja temperatura y alcalino con NaOH) sobre la reología, deshidratación, higienización y digestión anaerobia de lodos activados. Los tres tratamientos redujeron considerablemente la viscosidad del lodo debido a la solubilización de la las EPSs. Así mismo, la solubilización de la EPSs facilitó la expulsión del agua confinada dentro de los flóculos del lodo, mejorando la deshidratación mediante centrifugación. El tratamiento alcalino con dosis de NaOH elevadas fue el que más EPSs solubilizó, de manera que fue el que permitió extraer más agua y el que más aumentó la producción de metano, además de higienizar el lodo. No obstante, este tratamiento tiene el inconveniente de incrementar la concentración de sodio en el digestor, lo cual podría llegar a inhibir el proceso de digestión. Los ultrasonidos redujeron notablemente la viscosidad, además de mejorar la deshidratación y la digestión del lodo. Sin embargo, este tratamiento no fue capaz de higienizar el lodo. El tratamiento térmico a baja temperatura aumentó muy ligeramente la producción de metano (posiblemente debido al corto tiempo de exposición) y permitió deshidratar e higienizar el lodo.

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ElGharib, Mustafa [Verfasser], and Wolfgang [Akademischer Betreuer] Parak. "Enhancing the Physicochemical and Biological Properties of Anisotropic Nanoparticles by Rational Surface Engineering / Mustafa ElGharib ; Betreuer: Wolfgang Parak." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2020. http://d-nb.info/1216629463/34.

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Cable, Colin. "An examination of the effect of surface modifications on the physicochemical and biological properties of non-ionic surfactant vesicles." Thesis, University of Strathclyde, 1990. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21216.

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The physicochemical properties of non-ionic surfactant vesicles (NSV's), formed from the non-ionic surfactants I. II and IV (monoalkyl and dialkyl polyglyceryl ethers), were examined. The effects of incorporating polyoxyethylene cholesteryl ethers and charged molecules into the vesicular bilayer on these properties were examined and their potential as drug delivery vehicles for doxorubicin (DOX) investigated. The size and aqueous entrapment volume of vesicles were related to the preparation method, although charged molecules or increasing the hydrophilicity did affect both parameters. The vesicular surface charge, due to adsorbed hydroxyl ions or incorporated charged molecules, was reduced as the polyoxyethylene chain length of incorporated cholesteryl ethers was increased. The vesicular charge of vesicles containing cholesteryl polyoxyethylene(24)ether (SOL24) was unaffected by the encapsulation of DOX but encapsulation of the drug in positively charged vesicles markedly affected the charge against pH profile. Increasing the vesicular cholesterol content reduced the enthalpy of the phase transition, ultimately abolishing the peak between 33-50mol% cholesterol, while the peak shape was altered by the addition of charged molecules. Vesicular aggregation was induced by NaCl, although incorporation of charged molecules or SOL24 to the vesicular bilayer prevented this flocculation. DOX release from drug loaded vesicles was markedly reduced by the inclusion of cholesterol or stearylamine (SA) in the bilayer, while the incorporation of SOL24 produced a slight reduction. Empty vesicles containing SOL24 and SA molecules interacted with DOX molecules; SOL24 produced an immediate and reversible interaction and SA produced a delayed but apparently irreversible interaction. Administration of DOX loaded, SOL24 containing vesicles to mice reduced the peak cardiac concentration and produced a higher terminal plasma concentration compared with free drug. The co-administration of free drug with empty vesicles increased drug concentrations in the heart and kidney. The intravenous injection of DOX loaded. SA containing vesicles into mice bearing a subcutaneously implanted ROS tumour gave inconclusive results due to analytical problems, although the injection of empty vesicles with free drug behaved similarly to free drug alone. Drug loaded vesicles were much less effective at retarding tumour growth than either of the free drug containing samples despite fluorescence photomicrographs showing the majority of the vesicles residing within the tumour vasculature.

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11

Clemments, Alden Michael. "A Study Of The Physicochemical Properties Of Dense And Mesoporous Silica Nanoparticles That Impact Protein Adsorption From Biological Fluids." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/639.

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At the intersection of materials chemistry and biology, biomaterials have been successfully employed in an array of medical applications. From diagnostic tools to targeted drug delivery, the modular physical and chemical properties of these materials provide numerous applications. For example, porous nanoparticles have been widely integrated as vehicles to carry chemotherapeutics to localized tumor sites. By encapsulating these cytotoxic compounds within a porous framework, the commonly associated adverse side effects of conventional chemotherapeutics, such as Doxorubicin, have been greatly reduced. One such material, mesoporous silica, has received widespread attention due to its excellent biocompatibility, high surface area to mass ratio, tunable pore diameters and volumes, and robust surface chemistry. However, recent studies have demonstrated that exposing silica nanoparticles, and other synthetic materials, to biological milieu envelops the particles in layers of proteins and biomolecules. The resulting protein coat, known as the "protein corona", has been shown to have profound effects on bioavailability, cellular targeting, and cytotoxicity. Thus, in order to develop safe and effective particle-based therapies, it is of utmost importance to establish a more thorough understanding of this process. To examine how changes in surface chemistry influence protein adsorption, monodisperse, spherical mesoporous silica nanoparticles, ca. 50 nm, were modified with a variety of surface functionalizations, -NH2, -COOH, and -PEG. Exposing these materials to biological fluid revealed drastically different protein fingerprints, suggesting a strong correlation between the surface chemistry and the identity and composition of the protein corona. Quantification of the protein corona, i.e. mg protein/mg particles, was then achieved by performing thermogravimetric analysis. These values, in concert with spectral counts obtained by shotgun proteomics, illustrates a method for quantifying individual proteins present in the corona. Spherical, silica particles of varying diameters, 70-900 nm, were then synthesized to investigate how particle diameter may affect the biomolecular identity of the protein corona. Applying the previously described methods, it was found that mesoporous particles exhibit a higher affinity for low-molecular weight proteins compared to dense silica particles of similar diameters. Finally, stochastic optical reconstruction microscopy (STORM) was used to map protein adsorption/diffusion throughout as-prepared (pore diameter ~ 30 Å) .and large pore (pore diameter > 60 Å) mesoporous silica particles. By collecting three-dimensional data on the protein-adsorbed materials, a sphere-fitting algorithm could be applied to determine the center and radius of the host particle. This calculation demonstrated that the depth by which specific proteins diffused into the porous framework was a function of both the protein's molecular weight as well as the pore diameter.

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Al, Tafif Abdullah. "PREDICTION OF HUMAN SYSTEMIC, BIOLOGICALLY RELEVANT PHARMACOKINETIC PROPERTIES BASED ON PHYSICOCHEMICAL PROPERTIES OF CALCIUM CHANNEL BLOCKERS." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/2868.

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This research explored quantitative relationships (QSPKR) between different molecular descriptors and pertinent, systemic PK properties for 14 calcium channel blockers (CCB). Physicochemical properties (PC) such as molecular weight (MW), molar volume (MV), calculated logP (clogP), pKa, calculated logD7.4 (clogD), % ionized at pH 6.3 and pH 7.4, hydrogen bond donors (HBD), hydrogen bond acceptors (HBA), and number of rotatable bonds (nRot) were chosen as possible predictor variables for systemic PK properties for CCB, obtained from pertinent literature, assessing the PK of CCB after intravenous administration to healthy humans. All PC properties and molecular descriptors were computed using ACD-solubility/DB 12.01. Total body clearance (CLtot), steady-state volume of distribution (Vdss), total area under the plasma concentration-time profile (AUCoo), terminal half-life (t1/2), and fraction of drug excreted unchanged in urine (fe), if available, were obtained or derived from original references, exclusively from IV studies that administered CCB to healthy human volunteers. Several articles focused on drug interactions with grapefruit juice or the impact of renal/hepatic dysfunction, and in such cases, data from the healthy control group were used. Each study was evaluated for study design, PK sampling schedule, bioanalytical and PK analysis methods before inclusion into the final database. The assumption of linear systemic PK was verified by assessing AUCoo versus (IV) dose. Plasma protein binding information was collected from in-vitro experiments to obtain the fraction unbound in plasma (fu). Unbound volume of distribution at a steady state (Vdssu), unbound total (CLtotu), renal (CLrenu), and non-renal clearance (CLnonrenu) were estimated and compared with the relevant physiological references for Vdssu (plasma volume, blood volume, extracellular and intracellular spaces, total body water and body weight) and for the unbound clearances (liver blood flow, renal plasma flow, and glomerular filtration rate, GFR). Final PK property values were obtained by averaging across available studies. The distribution of both PC and PK properties were evaluated, and correlation matrices amongst PC properties were constructed to assess for collinearity. If two PC descriptors were found to be collinear, i.e. r, ≥ 0.8, only one of them was used in the final univariate analysis. Finally, univariate linear regression of all PK variables versus each molecular descriptor was performed; any relationship with p<0.05 and r2≥0.30 was considered to be statistically significant. The PC properties of the final 14 CCB were reasonably normally distributed with few exceptions. Overall, CCBs are small (MW range of 316-496 Da), basic and lipophilic (logD7.4 range of 1.5-5.1) molecules. On the other hand, for the PK properties, the distributions were found to be skewed with high standard deviations. Thus, all PK variables (except fu) were log-transformed. Although CCB are mostly highly plasma protein bound (fu range of 0.2-20%), they are characterized by extensive extravascular tissue distribution (Vdss range of 0.6-20.4 l/kg) and high, mainly metabolic, clearance (CLtot range of 3.7-131.7 ml/min/kg). Clevidipine is the only CCB undergoing extensive, extra-hepatic ester hydrolysis, responsible for the highest CLtot value. Urinary excretion for CCB is negligible. Amlodipine is a PK outlier due to its high Vdss (20.4 l/kg) and low CLtot (6.9 ml/min/kg, due to low hepatic extraction) with fu of 2%. Therefore, the final QSPKR analysis was performed including, as well as excluding amlodipine. Excluding amlodipine, the relationship between fu and logD7.4 was negative and significant (r2 of 0.4, n=12). The relationships between CLtotu, CLnonrenu and CLrenu and logD7.4 were found to be positive and significant (r2 between 0.6-0.7, n=3-12); none of the other PC variables affected any of the clearance terms. Although the relationship between Vdssu and logD7.4 was not significant (r2 of 0.25, n=12), it showed the expected positive slope. In fact, after removing bepridil (the remaining outlier in Vdssu), the relationship with logD7.4 became statistically significant (r2=0.46, n=11). The QSPKR obtained in this study for CCB, with logD7.4 being the main PC determinant for systemic PK properties, were similar to those previously reported for opioids, β-adrenergic receptor ligands and benzodiazepines. However, slope estimates for the relationships of CLnonrenu and CLtotu as a function of logD7.4 for CCB were higher compared to these previously studied compounds, which showed higher sensitivity, most likely as a result of their higher lipophilicity. Overall, lipophilicity measured as logD7.4 was found to be a statistically significant and plausible PC determinant for the biologically relevant systemic PK properties for CCB and other classes of drugs.

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Domingo, Olwen Charlotte [Verfasser]. "Investigations into the effect of nucleoside modifications on the physicochemical properties and biological function of DNA and RNA / Olwen Charlotte Domingo." Mainz : Universitätsbibliothek Mainz, 2013. http://d-nb.info/1043939938/34.

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14

Admire, Brittany. "The Estimation of Biologically and Environmentally Relevant Properties of Organic Compounds." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556008.

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The UPPER (Unified Physicochemical Property Estimation Relationships) model uses additive and non-additive parameters to estimate 21 biologically and environmentally important physicochemical properties of organic compounds. Thermodynamically sound relationships are used to predict boiling and melting points, aqueous and octanol solubilities, vapor pressure and the air-octanol, air-water and octanol-water partition coefficients. These properties determine the distribution and fate of organic compounds in biological and environmental systems. The model has been validated on a data set of 2000 hydrocarbons and polyhalogenated hydrocarbons, provides a simple and accurate method to predict the properties studied.

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15

Carroll, Hyrum D. "Biologically Relevant Multiple Sequence Alignment." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2623.pdf.

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Ferreira, Danielly Cunha Araújo. "Formulação à base de Epigalocatequina-3-galato, derivada do chá verde, desenvolvida para uso endodôntico: estudo físico-químico e biológico." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/58/58135/tde-14092015-105716/.

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O chá verde, obtido da Camellia sinensis, é uma das bebidas mais populares em todo o mundo e, recentemente, tem sido foco de pesquisas científicas por apresentar efeitos benéficos na saúde geral. Estudos laboratoriais e epidemiológicos sugerem que, dentre os polifenóis que compõem o chá verde, a Epigalocatequina-3-galato (EGCG) é o mais bioativo e responsável por sua ação antioxidante, anti-inflamatória, antimicrobiana, inativadora de LPS bacteriano, anticarcinogênica, antitumoral, anti-angiogênica, anti-hipertensiva e reparadora tecidual, podendo atuar na prevenção e tratamento do câncer, doenças cardiovasculares, neurodegenerativas, hepáticas e renais. Em diversas doenças ósseas, a EGCG também desempenha um importante papel protetor, atuando na indução da mineralização e inibição da osteoclastogênese. No entanto, seus possíveis efeitos na inflamação e na reabsorção óssea associadas à lesão periapical ainda não foram avaliados. Portanto, o objetivo do presente estudo foi desenvolver uma formulação para uso endodôntico à base de EGCG com propriedades físico-químicas e biológicas que permitam seu uso como curativo de demora entre sessões. As formulações testadas incluíram: EGCG diluída em água e diferentes concentrações de EGCG (1,25; 5; 10 e 20 mg/mL) veiculadas em polietilenoglicol 400 (PEG). O óxido de zinco foi utilizado como agente radiopacificador. Em função da possível degradação dos produtos fenólicos em função do ambiente e do tempo, uma solução obtida por meio do contato prolongado da EGCG com o dente também foi avaliada (produto da degradação). Inicialmente, foi realizada a caracterização físico-química da formulação de EGCG por meio de espectrofotometria em Ultravioleta/Visível (UV/Vis), em contato com soluções contendo zinco, óxido de zinco e acetato de zinco. Os estudos biológicos foram realizados para avaliar sua compatibilidade tecidual no tecido subcutâneo de camundongos, por meio da avaliação do extravasamento plasmático após 24 horas e da análise de aspectos macroscópicos e microscópicos aos 7, 21 e 63 dias após a inserção de tubos de polietileno contendo as formulações. Neste estudo, uma pasta a base de hidróxido de cálcio (Calen®) foi utilizada como controle. Na análise macroscópica, realizada por meio de fotografias, foram atribuídos escores aos parâmetros de ulceração epitelial, vascularização, necrose e edema. Na análise microscópica, realizada em microscopia de luz convencional e de fluorescência, foram avaliados os parâmetros de infiltrado inflamatório, vascularização, focos de abscessos, cápsula fibrosa, edema e necrose. Os escores dos resultados biológicos foram submetidos à análise estatística utilizando o teste do Qui-quadrado ou Exato de Fisher e para análise dos resultados quantitativos do extravasamento plasmático foi utilizada análise de variância (ANOVA), seguida pelo pós-teste de Tukey. O nível de significância adotado foi de 5%. Os estudos físico-químicos mostraram que a EGCG manteve seu comprimento de onda original em 274 nm quando associada ao óxido de zinco, tendendo à formação de uma banda de absorção em 325 nm. A associação da EGCG com acetato de zinco ocasionou diminuição da banda de absorção em 274 nm e formação de uma nova banda em 323 nm. Os estudos biológicos mostraram, nos parâmetros macroscópicos que, em todos os períodos avaliados, todas as formulações apresentaram compatibilidade tecidual, com ausência de ulceração epitelial, presença de leve necrose tecidual superficial, edema e vascularização, não havendo diferença significante entre os grupos avaliados (p>0,05). Na análise microscópica, em todos os períodos foi verificada ausência de focos de abscesso, edema e necrose e presença de suave ou moderado infiltrado inflamatório, cápsula fibrosa e neovascularização, semelhante entre todos os grupos (p>0,05). A avaliação dos espécimes corados com HE em microscopia de fluorescência favoreceu a visualização dos vasos sanguíneos e de fibras colágenas, constituindo metodologia adicional para esta finalidade. Na avaliação do extravasamento plasmático, o produto da degradação da ECGG apresentou extravasamento de corante azul de Evans por grama de tecido inferior (0,0514 ±0,0220 mg/mL) às demais formulações testadas (p<0,05). Conclui-se que a formulação tópica à base de EGCG, desenvolvida para uso endodôntico, apresenta propriedades físico-químicas estáveis e compatibilidade tecidual.
The green tea, obtained from the Camellia sinensis, is one of the most popular drinks in the world and has recently been in the focus of scientific research due its beneficial effects on general health. Laboratory and epidemiological studies suggest that, among the polyphenols found on green tea, the epigallocatechin-3-gallate (EGCG) is the most bioactive and responsible for its antioxidant, anti-inflammatory, anti-microbial, bacterial LPS inactivation, anticarcinogenic, anti-tumoral, anti-angiogenic, anti-hypertensive and tissue repair and can act in the prevention and treatment of cancer, cardiovascular disease, neurodegenerative, liver and kidney diseases. In several bone diseases, EGCG also plays a major protective role, acting in inhibition of osteoclastogenesis and induction of mineralization. However, their possible effects on inflammation and bone resorption associated to apical periodontitis have not been evaluated. Therefore, the aim of this study was to develop a EGCG based formulation for endodontic use with physicochemical and biological properties that allow its use as intracanal dressing between sessions. The formulations tested included: EGCG diluted in water and different concentrations of EGCG (1.25, 5, 10 and 20 mg/ml) diluted in polyethylene glycol 400 (PEG). Zinc oxide was used as radiopacifier agent. Due to the possible degradation of phenolic compounds as a function of the environment and time, a solution obtained through prolonged contact with the tooth EGCG was also evaluated (degradation product). Initially, physicochemical characterization of EGCG formulation was performed by ultraviolet spectrophotometry/Visible (UV/Vis) in contact with solutions containing zinc, zinc oxide and zinc acetate. Biological studies were conducted to evaluate its tissue compatibility with subcutaneous tissue of mice by means of the evaluation of plasma leakage after 24 hours and the examination of macroscopic and microscopic features at 7, 21 and 63 days after insertion of polyethylene tubes containing the formulations. In this study, a calcium hydroxide pastebase (Calen®) was used as control. The macroscopic analysis performed by means of photographs, assigned scores to epithelial ulceration, vascularization, necrosis and edema parameters. Microscopic examination performed in conventional and fluorescence microscopy assessed the inflammatory infiltrate, vascularization, abscesses spots, fibrous capsule, edema and necrosis parameters. The scores of biological results were statistically analyzed by the chisquare test or Fisher\'s exact and for the quantitative analysis of the results of plasma extravasation the analysis of variance (ANOVA) followed by Tukey\'s post-test were used. The significance level was 5%. The physico-chemical studies showed that EGCG maintained its original wavelength at 274 nm when added to zinc oxide, tending to the formation of an absorption band at 325 nm. The combination of EGCG with zinc acetate led to decreased absorption band at 274 nm and formation of a new band at 323 nm. Biological studies showed, in the macroscopic parameters in all periods, that all formulations showed tissue compatibility, with no epithelial ulceration, presence of mild superficial tissue necrosis, edema and vascularization, with no significant difference between the groups (p > 0.05). On microscopic examination, in all periods was verified absence of abscess foci, edema and necrosis and the presence of mild or moderate inflammatory infiltrate, fibrous capsule and neovascularization, similar among all groups (p> 0.05). The evaluation of the specimens stained with HE under fluorescence microscopy enhancve the visualization of the blood vessels and collagen fibers, constituting an additional methodology for this purpose. In the evaluation of plasma extravasation, the product of degradation of ECGG presented values of Evans blue dye extravasation by gram of tissue (0.0514 ± 0.0220 mg / mL) lower to the other tested formulations (p <0.05). It is concluded that the topical formulation based on EGCG developed for endodontic use, presented stable physical and chemical properties and tissue compatibility.

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Arruda, Vanilda Aparecida Soares de. "Pólen apícola desidratado: composição físico-química, qualidade microbiologica, compostos fenólicos e flavonoides, capacidade antioxidante e origem botânica." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-22062015-172352/.

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O pólen apícola, produto da aglutinação do pólen das flores com néctar e substâncias salivares das abelhas, tem sido promovido como suplemento da dieta humana por apresentar propriedades nutricionais e bioativas. Sessenta e duas amostras de pólen apícola desidratado foram avaliadas para as análises de compostos fenólicos, flavonoides, atividade antioxidante por três métodos (DPPH, sistema β-caroteno e ORAC), origem botânica, qualidade comercial (umidade, cinzas, lipídeos, proteínas e carboidratos) e sanitária (bolores e leveduras, aeróbios mesófilos, coliformes totais, E.coli, clostrídios sulfito redutores e S.aureus.), além da atividade antimicrobiana (Candida albicans, Escherichia coli, Staphylococcus aureus). Os valores obtidos para compostos fenólicos e flavonoides totais variaram de 12,60 a 84,22 mg GAE/g de pólen apícola (GAE: equivalentes em ácido gálico) e 1,90 a 36,85 mg de quercetina/g de pólen apícola respectivamente. O EC50, determinado pelo método do DPPH, variou de 0,35 a 13,42 mg pólen apícola/mL de extrato. Os extratos de pólen apícola apresentaram valores entre 52,58 e 98,37 % para o método do β-caroteno. Quando quantificada por ORAC, a atividade antioxidante medida ficou entre 132,98 e 575,85 µmol eq. trolox/g pólen apícola. Na avaliação da qualidade comercial foram obtidos os valores de 3,06% a 8,12% para umidade, de 1,94 a 4,61%, para cinzas, de 3,35 a 10,96% para lipídeos; de 17,73 a 34,73% para as proteínas, de 11,86 a 25,71% e de 2,77 a 15,87% para os açúcares frutose e glicose, respectivamente. Verificou-se que a presença do pólen apícola inibiu o crescimento de todos os microrganismos estudados. Candida albicans foi a mais resistente e o Staphylococcus epidermides foi o mais sensível. Observou-se 36 tipos polínicos diferentes, destacando-se: Cocos nucifera sp., Mimosa scabrella (Benth.), Mimosa caesalpiniaefolia sp., Eucalyptus sp., Myrcia sp., Asteraceae, Poaceae., Euphorbiaceae e Brassica que ocorreram com maior frequência entre as amostras estudadas. Foram observadas somente correlações moderadas e fracas entre os tipos polínicos presentes e os parâmetros avaliados para as amostras desidratadas de pólen apícola.
Bee pollen, a product of agglutination of flower pollen with nectar and bee salivary substances, has been promoted as a dietary supplement for human because of its nutritional and bioactive properties. Sixty-two samples of dehydrated bee pollen were analyzed for phenolics, flavonoids, antioxidant activity using three methods (DPPH, βcarotene and ORAC), botanical composition, commercial quality (moisture, ashes, lipids, proteins, carbohydrates), hygiene (aerobic mesophiles, yeasts and moulds, coliforms, Escherichia coli, Staphylococcus aureus and sulfite-reducing Clostridium), and antimicrobial activity (Candida albicans, Escherichia coli, Staphylococcus aureus). The obtained values for total phenolics ranged from 12.60 to 84.22 mg GAE/g bee pollen (GAE: gallic acid equivalents) while for total flavonoids ranged from 1.90 and 36.85 mg quercetin/g bee pollen. The EC50, determined by the DPPH method, ranged from 0.35 to 13.42 mg bee pollen/ml of extract. The bee pollen extracts showed values between 52.58 and 98.37% by β- carotene method. When measured by ORAC, antioxidant activity was between 132.98 and 575.85 µmols eq. trolox/g bee pollen. In the evaluation of commercial quality, the following results were achieved: 3.06% to 8.12% for moisture, 1.94 to 4.61% for ashes, 3.35 to 10.96% for lipids, 17.73 to 34.73% for proteins, from 11.86 to 25.71% and 2.77 to 15.87% for the carbohydrates glucose and fructose respectively. It was verified that the presence of the bee pollen inhibited the growth of all microorganisms studied. Candida albicans was the more resistant and Staphylococcus epidermides the more sensitive. Thirty-three pollen-types were identified mainly Cocos nucifera sp., Mimosa scabrella (Benth.) sp., Mimosa caesalpiniaefolia sp., Eucalyptus sp., Myrcia sp., Asteraceae sp., Poaceae sp., Euphorbiaceae sp. and Brassica sp. that occurred more frequently among the samples studied. It was observed only moderate and weak correlations between the pollen types present and the evaluated parameters for dehydrated samples of bee pollen

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Souza, Volnei Brito de. "Aproveitamento dos subprodutos de vinificação da uva Bordô (Vitis labrusca) para obtenção de pigmentos com propriedades funcionais." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-19042013-084817/.

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O objetivo deste trabalho foi produzir pigmentos em pó a partir dos subprodutos de vinificação da uva tinta, variedade Bordô (Vitis labrusca), através da secagem em spray dryer utilizando maltodextrina como agente carreador. Foram estudados os efeitos das condições de processo sobre algumas propriedades físico-químicas, além da estabilidade e da atividade biológica do material obtido. Extratos etanólicos das cascas e sementes da uva foram obtidos e concentrados até um terço do volume inicial. Este extrato foi então misturado com o agente carreador maltodextrina 10 DE nas concentrações de 10, 20 ou 30% e atomizado em spray dryer, com vazão de alimentação de 44 mL/min e temperaturas do ar de entrada de 130, 150 ou 170°C, num total de nove ensaios. Além disso, foi obtida uma amostra de extrato concentrado liofilizado, sem a presença do agente carreador, para efeito de comparação. Avaliou-se o rendimento do processo de atomização; e para as amostras obtidas determinou-se o teor de umidade, retenção de antocianinas, higroscopicidade e solubilidade em água, a fim de verificar a influência das condições de processo sobre essas características. Estas amostras também foram avaliadas quanto à morfologia, distribuição do tamanho de partículas e isotermas de sorção de umidade. Todas as amostras obtidas (atomizadas e liofilizada) foram avaliadas quanto à cor instrumental, espectroscopia de infravermelho, estabilidade durante a estocagem, presença de compostos bioativos (fenólicos, flavonóides, antocianinas e proantocianidinas), além de atividade antioxidante, antimicrobiana e de inibição da arginase de Leishmania. As condições de processo avaliadas (temperatura de secagem e concentração de agente carreador) tiveram forte influência nas características estudadas. O teor de umidade, a retenção de antocianinas, a morfologia e o tamanho das partículas, foram bastante influenciados pela temperatura de secagem e pela concentração de agente carreador, enquanto que a higroscopicidade sofreu maior influência da concentração de agente carreador. Esse parâmetro também apresentou grande influência nas isotermas de sorção de umidade das amostras. Não houve grande interferência do processo de secagem na composição química do material obtido, evidenciada pelos espectros de infravermelho. Quanto à avaliação da estabilidade durante a estocagem, foi observado que as amostras contendo maltodextrina conservaram mais as antocianinas e a cor, quando comparadas com as amostras sem carreador e os extratos líquidos, indicando, que o processo de secagem e a presença do carreador, promoveram um efeito protetor aos compostos e sua cor. Todas as amostras apresentaram altos teores de flavonóides totais, antocianinas, proantocianidinas e elevados valores de atividade antioxidante variando de 314,06 a 441,04 µmolesTE/g de extrato seco pelo método DPPH e de 993,32 a 1138,68 µmolesTE/g de extrato seco pelo método FRAP. Apresentaram atividade antimicrobiana principalmente contra Staphylococcus aureus e Listeria monocytogenes. Além disso, tiveram grande capacidade de inibir a enzima arginase de Leishmania com porcentagem de inibição variando de 54,60 a 83,43%. Os resultados encontrados sugeriram que o processo de secagem em spray dryer com maltodextrina, dos extratos obtidos dos subprodutos da uva Bordô, produziu pós com diversas características interessantes, como baixa higroscopicidade, alta solubilidade e estabilidade, além de grande potencial biológico. Tais resultados evidenciam que este subproduto da indústria vinícola pode ser aproveitado como fonte natural de ingredientes funcionais.
The aim of this work was to produce powder pigments from grape byproducts of Bordo variety (Vitis labrusca) by spray drying using maltodextrin as carrier agent. The effects of process conditions on some physicochemical properties, stability and biological activity of the product were studied. Ethanol extracts were obtained from grape pomace (skins and seeds) and concentrated to one-third the initial volume. This extract was then mixed with the carrier agent 10 DE maltodextrin at concentrations of 10, 20 or 30% and atomized in a spray dryer, with feed flow rate of 44 mL/min and inlet drying air temperatures of 130, 150 or 170°C a total of nine tests. In addition, a sample of freeze-dried concentrated extract without carrier agent was obtained for comparison. It was evaluated process yield and the samples obtained were initially evaluated for moisture content, anthocyanins retention, hygroscopicity and solubility in water, in order to verify the influence of process conditions on these characteristics. These samples were also evaluated for morphology, particle size distribution and moisture sorption isotherms. All samples (spray-dried powders and freeze-dried extract) were evaluated for instrumental color, infrared spectroscopy, stability during storage, presence of bioactive compounds (phenols, flavonoids, anthocyanins and proanthocyanidins) plus antioxidant activity, antimicrobial activity and inhibition of Leishmania arginase. Process conditions evaluated (inlet drying air temperature and carrier agent concentration) had a strong influence on the characteristics studied. The moisture content, anthocyanin retention, morphology and particle size of the samples were strongly influenced by drying temperature and carrier agent concentration while the hygroscopicity suffered greater influence of the carrier agent concentration. The concentration of carrier agent also had great influence on the moisture sorption isotherms of the samples. There was no significant interference of the drying process on the chemical composition of the material evidenced by infrared spectroscopy. Regarding the evaluation of stability during storage, it was observed that the samples containing maltodextrin, retained much more anthocyanins and original color when compared with the sample without a carrier or liquid extracts, indicating both, the drying process and the presence of carrier, promoted a protective effect to the compounds and its color. All samples showed high levels of flavonoids, anthocyanins, proanthocyanidins and high levels of antioxidant activity ranging from 314.06 to 441.04 µmolTE/g of extract (dry weight), by DPPH and 993.32 to 1138.68 µmolTE/g of extract (dry weight) by FRAP method. Most samples showed antimicrobial activity against Staphylococcus aureus and Listeria monocytogenes. Moreover, had great ability to inhibit the enzyme arginase of Leishmania with inhibition percentage ranging from 54.60 to 83.43%. The results suggest that the drying process of Bordo grape pomace extracts in a spray dryer with maltodextrin, produced powders with various interesting characteristics such as low hygroscopicity, high solubility and stability, and large biological potential. This shows that this byproduct of wine industry can be used as a natural source of functional ingredients.

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Touratier, Christine. "Comportement des protéines sarcoplasmiques de la viande de porc au cours du stockage et du chauffage : relations avec la qualité de la viande." Vandoeuvre-les-Nancy, INPL, 1992. http://docnum.univ-lorraine.fr/public/INPL_T_1992_TOURATIER_C.pdf.

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L’objectif de ce travail est la mise au point d'un prédicateur de la qualité de la viande de porc. La concentration en protéines sarcoplasmiques de viandes maturées (48 h p. M) présente des différences significatives suivant la qualité de ces viandes: 33. 5 mg/g de muscle pour les viandes normales, 24. 8 mg/g pour les viandes exsudatives, 28. 7 mg/g pour les viandes acides et 38. 6 mg/g pour les viandes DFD. L'évolution comparée de la teneur en protéines sarcoplasmiques de viandes normales et de viandes exsudatives entre 4 h et 168 h p. M à 4°C montre que: 1) l'insolubilisation progressive des protéines est plus marquée pour les viandes exsudatives (39. 3% d'insolubilisation pour les viandes exsudatives contre 25. 7% pour les viandes normales); 2) ces différences ne semblent pas exister in vivo; 3) les conditions de pH et de température dans les premières heures après l'abattage conditionnent en grande partie la qualité de la viande; 4) la CPK, la PHb et la TPI sont les protéines les plus fragilisées par la condition PSE. À 48 h p. M, la CPK présente une concentration de 5. 2 mg/g pour les viandes normales, la PHb 1. 5 et la TPI 1. 0 contre 1. 4, 0. 1 et 0. 2 pour les viandes exsudatives. Le chauffage accentue les différences observées au cours du stockage. Les 50% de dénaturation sont atteints à 58. 9°C pour les viandes normales, 51. 4 pour les viandes exsudatives, 56. 0 pour les viandes acides et 62. 0 pour les viandes DFD. Par ailleurs, l'insolubilisation des protéines induit parallèlement l'inactivation enzymatique. Un test prédictif de la qualité de la viande pourrait consister à maturer un échantillon de viande prélevé par biopsie, par un traitement thermique approprié, avant d'apprécier l'insolubilisation protéique ou l'inactivation enzymatique en résultant

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Falcone, Pin Bruno Nicolás. "Physicochemical properties of inhalation drugs." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648175.

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Sousa, Felipe Domingos de. "Physicochemical properties of plant hemicelluloses." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12378.

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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior
In this work six galactomannans (Adenanthera pavonina, Caesalpinia pulcherrima, Delonix regia, Dimorphera mollis, Prosopis glandulosa, Schizolobium parahyba) and three xyloglucans (Hymenaea courbaril, Mucuna sloanei e Tamarindus indica) were isolated from seed endosperm and cotyledon, respectively, by aqueous extraction followed by precipitation with ethanol. Yield of extraction, monosaccharide ratio, macromolecular parameters as well as molar mass distribution were determined and compared to guar gum (Cyamopsis tetragonoloba), LBG (Ceratonia siliqua) and xanthan (Xanthomonas campestris). Extraction yield in relation to seed mass ranged from 7.0 to 40.63%, with xyloglucan yields higher than the galactomannans ones. Schizolobium parahyba and Caesalpinia pulcherrima galactomannans presented the lowest protein content of 0.05% e 0.08%, respectively. The Mw values ranged from 0.09 â 3.37 x107 g mol-1 Flow curves of hemicelluloses solutions at 1% (w:v) were measured by varying the shear rate from 0.1 to 100 s-1. The resulting data were fit to the Power law e Herschel-Bulkley models. All the hemicelluloses presented shear-thinning behavior. Galactomannan and xyloglucans with different monosaccharide ratio showed similar consistency index; it may be influenced of the galactose distribution pattern on the chains and the interactions among the polysaccharides molecules. Rheological properties were compared and the results suggest new hemicelluloses sources which offer more profound applications in areas such as materials science, medicine e biology.
As hemiceluloses sÃo polissacarÃdeos presentes na parede celular de vegetais, onde funcionam como polissacarÃdeos de reserva e possuem uma cadeia principal composta por ligaÃÃes β-(1→4) em configuraÃÃo equatorial. Neste trabalho, hemiceluloses de sementes foram avaliadas quanto as suas propriedades reolÃgicas. Como resultado, galactomananas endospÃrmicas de Adenanthera pavonina, Caesalpinia pulcherrima, Delonix regia, Dimorphera mollis, Prosopis glandulosa e Schizolobium parahyba e xiloglucanas cotiledonÃrias de Hymenaea courbaril, Mucuna sloanei e Tamarindus indica foram isoladas por extraÃÃo aquosa, seguida por precipitaÃÃo em etanol. O rendimento das extraÃÃes, razÃo monossacarÃdica, parÃmetros macromoleculares, assim como distribuiÃÃo de massa molar foram determinados e comparados Ãs jÃ comercializadas goma guar (Cyamopsis tetragonoloba), LBG (Ceratonia siliqua) e goma xantana (Xanthomonas campestris). O rendimento das extraÃÃes em relaÃÃo Ã massa das sementes mostrou um intervalo de 7,0 a 40,63%, com os maiores valores para as xiloglucanas. Galactomananas de Schizolobium parahyba e Caesalpinia pulcherrima apresentaram os menores percentuais de proteÃnas, 0,05% e 0,08%, respectivamente. Valores de Mw variaram dentro de um intervalo entre 0,09 â 3,37 x107 g mol-1. Curvas de fluxo das soluÃÃes de hemiceluloses a 1% (m:v) foram obtidas pela variaÃÃo da taxa de cisalhamento entre 0,1 a 100 s-1. Os dados obtidos foram analisados pelos modelos de Lei das PotÃncias e Hershel-Bulkley demonstrando carÃter pseudoplÃstico para todas as hemiceluloses estudadas nessa concentraÃÃo. Galactomananas e xiloglucanas com diferentes razÃes monossacarÃdicas apresentaram Ãndice de consistÃncia similar, provavelmente influenciado pelo padrÃo de distribuiÃÃo de galactose nas cadeias e as interaÃÃes entre as molÃculas desses polissacarÃdeos. As propriedades reolÃgicas foram comparadas e os resultados sugerem novas fontes de hemiceluloses que permitem mais aplicaÃÃes em Ãreas como ciÃncia dos materiais, medicina e biologia.

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Lansita, Janice A. (Janice Ann) 1975. "Physicochemical characterization of immortal strand DNA." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/18038.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Biological Engineering Division, 2004.
Includes bibliographical references.
Adult tissue differentiation involves the generation of distinct cell types from adult stem cells (ASCs). Current understanding of tissue differentiation mechanisms is based on studies of protein and RNAs that asymmetrically segregate between daughter cells during embryogenesis. Whether or not other types of biomolecules segregate asymmetrically has not been widely studied. In 1975, John Cairns proposed that ASCs preferentially segregate the oldest parental template DNA strands to themselves and pass on newly replicated DNA strands to their differentiating progeny in order to protect the stem cell from inheriting DNA replication mutations. This laboratory has shown non-random chromosome segregation in murine fetal fibroblasts that model asymmetric self-renewal like ASCs. In these cells, chromosomes that contain the oldest DNA strands co-segregate to the cycling daughter stem-like cells, while chromosomes with more recently replicated DNA segregate to the non-stem cell daughters. Previously, cytological methods were reported to elucidate non-random segregation in these cells. This dissertation research provides additional confirmation of the mechanism using physicochemical methods. Specifically, buoyant density-shift experiments in equilibrium CsCl density gradients were used to detect co-segregated "immortal DNA strands" based on incorporation of the thymidine base analogue bromodeoxyuridine. In addition, DNA from cells undergoing non-random mitotic chromosome segregation was analyzed for unique DNA base modifications and global structural modifications (by HPLC and melting temperature analyses). To date, these studies show no significant differences compared to control randomly segregated DNA. Components of the mitotic chromosome separation
(cont.) apparatus that might play a role in the co-segregation mechanism were also evaluated. Two homologous proteins, essential for proper chromosome segregation and cytokinesis, Aurora A kinase and Aurora B kinase, were highly reduced in expression in cells retaining immortal DNA strands and may indicate a role for them in the immortal strand mechanism. These studies independently confirm the immortal strand mechanism and provide methods for its detection in other cell lines. In addition, observed changes in chromosome segregation proteins that are potential candidates for involvement in the mechanism have revealed a new area of investigation in the laboratory. These findings are relevant to understanding normal tissue development, cancer, and aging.
y Janice A. Lansita.
Ph.D.

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23

Wangsa-Wirawan, Norbertus Djajasantosa. "Physicochemical properties of protein inclusion bodies." Title page, contents and introduction only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phw2465.pdf.

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Bibliography: leaves 182-198. Improvements in the current production system of inclusion bodies and the downstream processing sequence are essential to maintain a competitive advantage in the market place. Optimisation of fermentation is considered to improve production yield; then flotation as a possible inclusion body recovery method.

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24

ABBAS, IBRAHIM RASHEED. "PHYSICOCHEMICAL PROPERTIES OF TEPARY BEAN STARCH." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/183997.

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The composition of tepary beans Phaseolus acutifolius var. latifolius was determined; starch (41%) and protein (26.3%) were the predominant components. The physical, physicochemical, rheological, structural and nutritional properties of the isolated starch and its suitability in food products were evaluated. Starch granules were spherical to oval with a typical legume starch birefringence pattern. They appeared smooth and showed a normal distribution of diameters (range 15.5 - 59.9 μ; mean 33.5 μ). Tepary starch had an amylose content of 30.7% and a gelatinization temperature range of 70.5 - 84.0°C. Other physicochemical values were as follows: phosphorus, 0.01%; iodine binding capacity, 6.14%; alkali number, 8.97; inherent viscosity, 2.44 ml/g; water binding capacity, 82.1%; swelling power, 13; solubility, 17.9%; and sag, 6.26%. Fractionation provided an amylose fraction with a β-amylolysis of 76.3%, limiting viscosity of 83.5 ml/g and a DP(η) of 618. Amylopectin (iodine binding capacity, 0.88%) had a DP(η) of 1094, limiting viscosity of 91.1 ml/g and CL, OCL, and ICL values of 33, 22 and 10 glucose units, respectively. Gelatinization of tepary starch was a single-step process. Pasting viscosity was stable when starch suspensions were cooked at 95°C for 15 min; viscosity progressively increased when pastes cooled to 50°C. At 4 and 6%, tepary starch pastes resembled a type C viscosity pattern, whereas at 7% and above, pasting behavior exhibited a type B pattern. Pastes were stable at pH 5 to 9 but showed faster breakdown and no retrogradation at pH 3. Addition of sucrose and salt changed rheological behavior; 2% oil had no effect on pasting. Sensory evaluation of tepary starch vanilla pudding established its consumer acceptability. In vitro determination indicated that raw tepary starch was poorly digested (8%). Digestibility improved (from 8 to 82%) upon cooking. Raw corn starch was more digestible (25.6%) than tepary starch. Freeze-drying reduced the hydrolysis of all materials evaluated (i.e. 8.64 to 3.21%, 8.03 to 2.63% and 25.6 to 17.8% for tepary flour, tepary starch and corn starch, respectively). Autoclaving decreased the digestibility of tepary flour (8.64 to 5.72%), and tepary starch (8.03 to 7.38%), but it slightly improved that of corn starch (25.6 to 27.7%).

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25

Pathomrungsiyounggul, Pattavara. "Physicochemical Properties of Calcium-fortified soymilk." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518215.

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26

Morimoto, Daichi. "Novel physicochemical properties of polyubiquitin chains." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199328.

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27

Chandrashekhar, Mangesh. "Biological and physicochemical studies on polymer-DNA delivery systems." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395573.

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28

Gorgone, Christine Ann. "Physicochemical and biological treatability study of textile dye wastewater." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-05022009-040707/.

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29

Nilsson, Johanna. "CORRELATIONS BETWEEN PHYSICOCHEMICAL PROPERTIES IN MATERIALS COMPRISING MICROFIBRILLATED CELLULOSE : CORRELATIONS BETWEEN PHYSICOCHEMICAL PROPERTIES IN MATERIALS COMPRISING MICROFIBRILLATED CELLULOSE." Thesis, Umeå universitet, Kemiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185526.

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Microfibrillated cellulose (MFC) films have gained a lot of industrial interest lately dueto their good barrier properties and good mechanical strength. In this study it wasinvestigated whether rheological characteristics and conductivity of MFC dispersionscomprised of different MFC grades could be correlated to tensile properties of the MFCfilms produced from the corresponding MFC dispersion. A rheological characterizationmethod was developed for MFC dispersions with 3 wt% MFC and a secret additiveusing a dynamic rotational rheometer and a smooth “plate to plate” geometry. Themethod consisted of an amplitude sweep, a frequency sweep, and a controlled shearrate measurement. Two predicting OPLS models were created in SIMCA: model 1correlated values from rheological measurements and ionic conductivity to tensileproperties and model 2 correlated MFC grades to tensile properties. A slight correlationbetween MFC rheology and tensile properties could be observed, but due to the lowpredictive ability of model 1 (Q2=0.47) it was deemed that the model was insufficientas a tool for facilitated predictions of new samples. It was concluded that tensileproperties are more correlated to the composition of MFC dispersions than whatrheological characteristics and ionic conductivity the dispersions display, based on thegood predictive ability of model 2 (Q2=0.59).

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30

Ge, R. "Measurement of Physicochemical Properties of Ionic Liquids." Thesis, Queen's University Belfast, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527700.

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31

MacLaughlin, Fiona Caroline. "DNA delivery : physicochemical properties of DNA:polycation complexes." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338437.

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32

Badruddin, Ahmad Fasihuddin. "Physicochemical characterisation and properties of sago starch." Thesis, University of Salford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265740.

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33

Kaiser, Achim. "Physicochemical Properties and Synthesis of Oligothiophene Macrocycles." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-64614.

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34

Zhang, Yue. "The Physicochemical Properties of Secondary Organic Materials." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17467502.

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The physicochemical properties of the secondary organic materials (SOMs) that constitute the particle phase have potentially important consequences for the growth, the reactivity, and ultimate fate of atmospheric organic aerosols, thereby affect climate, human health and visibility. A quantitative analysis of the physicochemical properties of the SOMs is important, but challenging. This thesis presents laboratory studies of α-pinene derived SOMs, which is one of the major components of secondary organic aerosols (SOAs) in the forests, by combing a flow tube reactor, aerosol particle mass analyzer (APM) and other online/offline measurement techniques. A water-jacketed constant temperature flow tube reactor was built to produce SOM particles grown from either condensation or coagulation. Different ratios of α-pinene enantiomers were mixed and injected into the flow tube reactor for dark ozonolysis. A matrix of organic precursor and ozone concentrations was designed and tested in order to determine the optimal concentration to switch between condensation and coagulation. Results show that at 51 ± 1 ppm O3, condensation is the dominant growth mechanism when the α-pinene concentration is 0.125 ± 0.001 ppm, and coagulation is the dominant growth mechanism when the α-pinene concentration increases to 1.00 ± 0.03 ppm. A combination of both growth mechanisms is observed when the α-pinene concentration is in between the described values. The study also proposed and tested the hypothesis that a 50:50 mixture of α-pinene enantiomers may result in SOM particles that have different physical properties, such as number-diameter distributions, when compared with those particles generated from a single enantiomer of α-pinene. The experiment was conducted within the condensational growth regime so that the chirality induced structure differences in oligomers can be maximized during the nucleation and condensation. Nevertheless, our analysis indicates that, after removing the effects of ozone and temperature, the chirality-induced effects are minimal and within our detection limit. Even though the results were negative, the method used in this experiment provided useful experience for the viscosity related experiments in this thesis. Another important property of the SOM is its viscosity. The viscosities of atmospheric particles determine whether their interactions with surrounding gases are confined to the surface or can proceed to the interior. Viscosities affect the gas-particle diffusion rate, and ultimately influences the SOM’s other physical properties, such as particle size, and chemical properties, such as reactivity. The work presented in this thesis estimates the viscosity of submicron organic particles while they are still suspended as an aerosol without further post-processing techniques that can have the possibility of altering the properties of semivolatile materials. The results show that the studied particles are semisolid up to 58% relative humidity (RH) and may become liquid only at a higher RH. These results imply that atmospheric particles, at least those similar to the ones studied and for low to middle RH regimes, are expected to reach equilibrium only rather slowly with the chemical composition of the gas phase, sometimes on timescales longer than the actual residence time of the particles in the atmosphere. Last but not the least, the results of offline particle analysis from two collaboration studies are also discussed in this thesis. The results show how water vapor, or RH, affects the physicochemical properties of the α-pinene derived SOM particles. In one study, the diffusivity is underestimated by approximately 8 orders of magnitude if calculated from the Stokes-Einstein equation, which suggests the breakdown of Stokes-Einstein equation for small gas molecules. The second study shows the surface properties of SOM particles can be influenced by the RH, leading to a difference of the gas-particle interactions at the particle surface.
Engineering and Applied Sciences - Engineering Sciences

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35

Kubota, Keigo. "Physicochemical properties of alkali perfluoroalkylsulfonylamides and fluorosulfonylamides." Kyoto University, 2010. http://hdl.handle.net/2433/120412.

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36

Blake, S. M. "Physicochemical studies on sodium hyaluronate." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381670.

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37

張志田 and Zhitian Zhang. "Nutritional quality and starch physicochemical properties in sweetpotato." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31242728.

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38

Zhang, Zhitian. "Nutritional quality and starch physicochemical properties in sweetpotato." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23241950.

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39

Chung, Henry E. (Henry Edmund). "Physicochemical properties of the alligator lizard tectorial membrane." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/39362.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.
Includes bibliographical references (leaves 44-46).
by Henry E. Chung.
M.Eng.

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40

Bureekaew, Sareeya. "Studies on Physicochemical Properties of Porous Coordination Polymers." 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/88045.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第15007号
工博第3181号
新制||工||1478(附属図書館)
27457
UT51-2009-R731
京都大学大学院工学研究科合成・生物化学専攻
(主査)教授北川進, 教授杉野目道紀, 教授濵地格
学位規則第4条第1項該当

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41

Chen, Yu-Lin. "Prediction of physicochemical properties for Fe3+ chelating agents." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/prediction-of-physicochemical-properties-for-fe3-chelating-agents(42cafffb-3121-42be-a1e1-d11df51eb62a).html.

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Iron is vital for all living creatures but becomes toxic when it exceeds the levels catered for by their natural cellular buffering mechanisms, causing free radical formation via the Fenton reaction and ultimately, therefore, leading to oxidative stress. In such situations, for example in repeatedly transfused patients suffering from β-thalassaemia or sickle cell anaemia, iron chelation therapy is required. Desferioxamine (DFO), the most widely used therapeutic chelator, is a hexadentate ligand possessing a very high affinity for Fe3+, but it is not orally active. 3-hydroxypyridin-4-ones (HPOs), the more recently introduced synthetic alternatives, have also been shown to be useful therapeutic chelators, demonstrating the essential affinity and selectivity for Fe3+ along with good oral activity. Deferiprone, a typical HPO, has emerged as a prominent therapeutic, able to remove accumulated excess iron from the heart and mitochondria. However, because Deferiprone has some drawbacks of relatively high metabolic instability and a side effect of lowering white blood cell count for a small number of patients, the search continues for other such synthetic chelators with improved properties. In the work reported here, various computational studies have been performed to aid in the rational design of Fe3+ chelators, with their physicochemical properties (pKa, Fe3+ affinity, hydration and membrane permeability) predicted by means of quantitative structure property relationship (QSPR) methods, quantum mechanical (QM) calculations, and molecular dynamic (MD) simulations. The pKa and Fe3+ affinity were also studied experimentally with a novel approach devised for dealing with ligands possessing substituents with hydrogen bond donor and/or acceptor groups. The pKa values predicted using QSPR and QM static calculations (Gaussian 09) were found to differ very significantly from the experimentally determined values. When data from the QM static calculations were combined with a regression model, however, the pKa predictions were significantly improved, with the predicted values then within ± 0.2 log units of the experimental values, and computing times of the order of 1 day per molecule. These calculations also allowed the determination of possible deprotonation sequences for the predicted compounds. Further pKa predictions were made by means of QM MD calculations, using Car-Parrinello molecular dynamics (CP-MD). These simulations were found to yield pKa values within ±0.3 log units of the experimental values but involved much longer computing times (of the order of 20 days per molecule). In addition, however, the CP-MD simulations also provided valuable insights into the atomistic details of the proton transfer mechanism and the solvation structure and dynamics at all stages of the reaction. For the three HPOs studied, it was observed that proton transfer takes place along a chain of three H20 molecules, although direct hydrogen bonds were observed to form transiently. The (Fe3+) log /C, predictions for the HPOs were made using an entirely novel QM-based methodology (and without knowledge of the chelator pKa values), yielding log K-\ values within ± 0.32 log units of the experimental values. For the preparation of membrane permeability study, novel Chemistry at HARvard Molecular Mechanics (CHARMM) force fields specifically for use in HPO simulations were developed. These new force fields were validated using Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) MD simulations of the chelators’ behaviour in aqueous solution.

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42

Rogerson, Alan. "A physicochemical and biological evaluation of non-ionic surfactant vesicles (niosomes)." Thesis, University of Strathclyde, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317985.

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43

Opdycke, Mary Ellen. "Physicochemical and biological treatment of a textile dyeing and finishing wastewater." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-01312009-063352/.

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44

Карпенко, Ілона Василівна. "Біотехнологія рамноліпідних поверхнево-активних продуктів штаму pseudomonas sp. PS-17 та їх застосування для олійних рослин". Thesis, КПІ ім. Ігоря Сікорського, 2017. https://ela.kpi.ua/handle/123456789/19098.

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Дисертація присвячена розробленню технології отримання поверхнево-активних речовин штаму Pseudomonas sp. PS-17 та технологій їх застосування для вирощування олійних рослин. Встановлено ефективність використання економічно вигідних субстратів (фузу олійного, пересмаженої олії), композицій їх з гліцерином, а також дробного способу їх подачі для синтезу рамноліпідних ПАР: вихід підвищено на 18-39% порівняно з гліцерином. Удосконалено способи виділення ПАР, одержано економічно вигідні продукти. Методом лінійних багатопараметрових рівнянь визначено оптимальні екстрагенти рамноліпідів. Показано, що отримані ПАР мають високу поверхневу (28,3 мН/м), емульгувальну (індекс Е24 60-80%), змочувальну активність, впливають на проникність клітинних мембран мікроорганізмів, рослин, підсилюють дію біоцидів, фітогормонів. Встановлено стимулювальний вплив ПАР на ріст олійних рослин, їх фізіолого-біохімічны показники. Ефективність отриманих ПАР у вирощуванні соняшника доведено у дрібноділянкових і виробничому дослідах: за їх використання значно підвищувалися ростові показники та якість врожаю. Розроблено технологічну та апаратурно-технологічну схему виробництва ПАР штаму Pseudomonas sp. PS-17, яка дозволяє одержати 5 форм цільових продуктів для практичного застосування у рослинництві.
The dissertation thesis is devoted to the development of the biotechnology of microbial synthesis of the surface-active substances by the strain Pseudomonas sp. PS-17 and their application in cultivation of oil-bearing plants. The effectiveness of the application of cost-beneficial substrates (used frying oil and waste from production of sunflower oil – phosphatide concentrate) was established for the synthesis of rhamnolipid surfactants by the strain Pseudomonas sp. PS-17 when applied alone and in combination with glycerol. It was shown that the use of combined substrates contributed to the increased yields of rhamnolipids if compared to the media with monosubstrates. When using a mixture of glycerol and used frying oil or phosphatide concentrate as carbon sources the final concentration of rhamnolipids can be increased on 18-39 %. The developed approaches of the synthesis of rhamnolipid surfactants will enable the decrease of the overall cost of biosurfactant production if compared with the cost of the production on glycerol alone. The processes of rhamnolipid surfactant separation were optimized: enzymatic hydrolysis (using protease C enzyme) of post-fermentative culture liquid, precipitation of rhamnolipid biocomplex (RBC) from culture liquid supernatant (CLS) by adjusting temperature regime. Economically viable forms of targeted products based on exo- and endomethabolites of Pseudomonas sp. PS-17 and methods of their isolation were proposed. Optimum solvents for the extraction of rhamnolipids from CLS were determined using the method of linear multiparameter equations. Physico-chemical and biological properties of the products based on surfactants of Pseudomonas sp. PS-17 were established: surface activity, emulsification of hydrophobic substances, wetting of surfaces, the influence on the permeability of cell membranes of microorganisms and plants, the activity of surfactants on the major groups of phytohormones (auxins, cytokinins, gibereline acid). The antimicrobial activity of surfactants against phytopathogen microorganisms was shown, and highly effective formulations of rhamnolipid surfactant with ethylthiosulfonate-biocide were designed. A stimulating action of the synthesized rhamnolipid surfactants on the growth of oil-bearing plants was established. It was shown that the effect of the biosurfactants on microorganisms and plants via the changes in their physiological and biochemical characteristics (growth rate, cell membrane permeability, activity of enzymes and phytohormones). The possibility of application of the obtained biosurfactants in agriculture as plant growth regulators was established. The effectiveness of the developed biosurfactants in growing sunflower was confirmed by a small plot experiments, as well as in the field experiment. It was shown that rhamnolipid surfactants promote growth and quality of the crops (the mass of 1000 seeds, flower diameter, fat and protein content in the seeds). The process flow and equipment diagrams of industrial production of rhamnolipid surfactants of Pseudomonas sp. PS-17 using a vortex bioreactor were developed, 5 forms of rhamnolipid products for practical use in cropping were obtained.
Диссертация посвящена разработке технологии синтеза поверхностно-активных веществ штаммом Pseudomonas sp. PS-17 и их применению для выращивания масличных растений. Установлена эффективность использования экономически выгодных субстратов (фуза масляного, пережаренного масла), их смесей с глицерином, дробного способа их подачи для синтеза рамнолипидных ПАВ, выход увеличен на 18-39% относительно глицерина как моносубстрата. Усовершенствованы способы выделения рамнолипидных ПАВ, получены экономически выгодные продукты. Методом линейных многопараметровых уравнений найдены оптимальные экстрагенты рамнолипидов из СКЖ. Разработанные ПАВ имеют высокую поверхностную (28,3 мН/м), эмульгирующую (индекс Е24 60-80%), смачивающую активность, влияют на проницаемость клеточных мембран микроорганизмов, растений, усиливают действие биоцидов, фитогормонов. Показано стимулирующее действие полученных ПАВ на рост масличных растений, их физиолого-биохимических показателей. Эффективность рамнолипидных ПАВ при выращивании подсолнечника установлена в мелкоучастковых, производственных опытах: значительно увеличены ростовые показатели, а также качество урожая. Разработана технологическая и аппаратурно-технологическая схемы промышленного производства рамнолипидных ПАВ Pseudomonas sp. PS-17 для получения 5 форм продуктов для практического применения в растениеводстве.

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45

Acharya, Sandipta. "Some Aspects of Physicochemical Properties of DNA and RNA." Doctoral thesis, Uppsala University, Department of Bioorganic Chemistry, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6741.

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This thesis is based on nine research publications (I – IX) on structure and reactivity of RNA vis-à-vis DNA. The DNA and RNA are made of flexible pentose sugar units, polyelectrolytic phosphodiester backbone, and heterocyclic nucleobases. DNA stores our genetic code, whereas RNA is involved both in protein biosynthesis and catalysis. Various ligand-binding and recognition properties of DNA/RNA are mediated through inter- and intra-molecular H-bonding and stacking interactions, beside hydration, van der Waal and London dispersion forces. In this work the pH dependant chemical shift, pK_a values of 2'-OH group as well as those the nucleobases in different sequence context, alkaline hydrolysis of the internucleotidic phosphodiester bonds and analysis of NOESY footprints along with NMR constrained molecular dynamics simulation were used as tools to explore and understand the physico-chemical behavior of various nucleic acid sequences, and the forces involved in their self-assembly process. Papers I – II showed that the ionization of 2'-OH group is nucleobase-dependant. Paper III showed that the chemical characters of internucleotidic phosphate are non-identical in RNA compared to that of DNA. Papers IV – VI show that variable intramolecular electrostatic interactions between electronically coupled nearest neighbor nucleobases in a ssRNA can modulate their respective pseudoaromatic character, and result in creation of a unique set of aglycons with unique properties depending on propensity and geometry of nearest neighbor interaction. Paper VII showed that the cross-modulation of the pseudoaromatic character of nucleobases by the nearest neighbor is sequence-dependant in nature in oligonucleotides. Paper VIII showed that the purine-rich hexameric ssDNA and ssRNA retain the right-handed helical structure (B-type in ssDNA and A-type in ssRNA) in the single-stranded form even in absence of intermolecular hydrogen bonding. The directionality of stacking geometry however differs in ssDNA compared to ssRNA. In ssDNA the relatively electron-rich imidazole stacks above the electron-deficient pyrimidine in the 5' to 3' direction, in contradistinction, the pyrimidine stacks above the imidazole in the 5' to 3' direction in ssRNA. Paper IX showed that the pK_a values of the nucleobases in monomeric nucleotides can be used to show that a RNA-RNA duplex is more stable than a DNA-DNA duplex. The dissection of the relative strength of base-pairing and stacking showed that the relative contribution of former compared to that of the latter in an RNA-RNA over the corresponding DNA-DNA duplexes decreases with the increasing content of A-T/U base pairs in a sequence.

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Mhd, Sarbon Norizah. "Nutritional and physicochemical properties of chicken proteins and peptides." Thesis, University of Surrey, 2011. http://epubs.surrey.ac.uk/804305/.

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47

Malcolmson, Carole A. "The physicochemical properties of nonionic oil-in-water microemulsions." Thesis, King's College London (University of London), 1992. https://kclpure.kcl.ac.uk/portal/en/theses/the-physicochemical-properties-of-nonionic-oilinwater-microemulsions(4315649d-d2d1-497d-9a76-05bc06f7f9a1).html.

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ROCHA, RENATO MOUTINHO DA. "INFLUENCE OF SYNTHESIS CONDITIONS ON PHYSICOCHEMICAL PROPERTIES OF SNO2." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7368@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Resultados de testes preliminares para a reação de obtenção de formaldeído a partir de metóxi metano (DME) utilizando um catalisador Mo/SnO2 indicaram a necessidade de sistemas altamente ativos. Considerando-se que espécies dispersas de Mo parecem ser as mais efetivas para essa reação, e que a obtenção dessas espécies deve ser favorecida com o uso de um suporte de elevada área específica, estudou-se, neste trabalho, a influência dos parâmetros de síntese nas propriedades fisico-químicas do SnO2 preparado a partir de três diferentes métodos: a partir do ataque de Sn0 com HNO3, a partir da reação entre Sn+4 e NH4OH, e a partir da reação entre Sn+4 e dodecilamina. Foram realizadas alterações na forma de mistura das soluções, no tempo e na temperatura de reação, e na razão de aquecimento durante a calcinação. As amostras obtidas foram caracterizadas por adsorção de N2 para medições de área específica e distribuição de tamanho de poros, difração de raios-X e espectroscopia de reflectância difusa na região do UV-visível. Os resultados mostraram que todas as amostras obtidas são mesoporosas, embora apresentem diferentes valores de área específica, de tamanho de cristal, e de diferença de energia entre os orbitais HOMO-LUMO. Dentre os métodos estudados, o que partiu da reação entre Sn+4 e NH4OH apresentou maior sensibilidade às alterações realizadas, e as amostras assim obtidas apresentaram maiores valores de área específica; por outro lado, as amostras obtidas a partir do ataque de Sn0 com HNO3 não apresentaram variações texturais e estruturais significativas. Os resultados indicam ainda que, dentre os parâmetros alterados, a temperatura e o tempo da reação parecem ser os mais importantes.
Preliminary tests on the reaction for formaldehyde production from metoxi methane (DME) using a Mo/SnO2 catalyst have indicated the necessity of highly active systems. Dispersed species of Mo seem to be the most effective for this reaction which may be favored by the use of a support of high specific area. Therefore the influence of the synthesis parameters on the physicochemical properties of the SnO2 has been studied in this work. This oxide has been prepared by three different methods: by the oxidation of Sn0 using HNO3, by the reaction of Sn+4 with NH4OH, and by the reaction of Sn+4 with dodecylamine. Variations on the way of mixing the solutions, on the time and the temperature of the reaction, and on the heating rate of the calcinations step have been carried out. These samples have been characterized by N2 adsorption for measurements of specific area and pore size distributions, X-ray diffraction and UV-visible diffuse reflectance spectroscopy. The results have shown that all samples are mesoporous even though they have exhibited distinct values of specific area, crystal size and HOMO-LUMO gap energy. The reaction of Sn+4 with NH4OH has presented the greatest sensitivity to the synthesis parameters, and it has provided samples with the highest specific area values. However the samples prepared by the oxidation of Sn0 using HNO3 have not been influenced. The results have also indicated that the temperature and the reaction time seem to be the most important parameters.

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Godber, Benjamin L. J. "Physicochemical and kinetic properties of human milk xanthine oxidoreductase." Thesis, University of Bath, 1998. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760718.

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Takigawa, Toshikazu. "CRITICAL BEHAVIOR AND PHYSICOCHEMICAL PROPERTIES OF HYDROPHILIC POLYMER GELS." Kyoto University, 1995. http://hdl.handle.net/2433/77859.

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