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1
Kästle, Ralf. "CO-laser photoacoustic spectroscopy of fatty acid molecules /". [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11154.
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Vogel, Jörn-Oliver. "Co-deposited films of rod-like conjugated molecules". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2009. http://dx.doi.org/10.18452/15978.
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In dieser Arbeit wird die Phasenseparation und Mischung zwischen konjugierten Stäb-chenmolekülen in dünnen Filmen untersucht. Hauptaugenmerk liegt darauf zu ergrün-den welche molekularen Eigenschaften zu Mischung und/ oder Phasenseparation füh-ren. Mit den 5 Molekülen Pentacen (PEN), Quaterthiophen (4T), Sexithiophen (6T), p-Sexiphenylen (6P), alpha,omega-Dihexylsexithiophen (DH6T) werden Materialpaare zusammen gestellt, die sich in den Parametern „optische und elektrische Eigenschaf-ten“, „Länge des konjugierten Kerns“ und Alkylkettensubstitution unterscheiden. Alle Schichten werden mittels organischer Molekularstrahlabscheidung auf die Substrate Siliziumoxid und Mylar, einer PET Folie, simultan von zwei Quellen aufgedampft. Das Mischungsverhältnis wird mittels der individuellen Aufdampfraten eingestellt und eine Gesamtrate von 0.5 nm/min eingehalten. Es wird Phasenseparation für Materialpaare mit ungleicher konjugierter Kernlänge, z.B. [4T/6T], beobachtet. Erstaunlicherweise führt die Co-Verdampfung von Molekülpaaren mit ähnlicher konjugierter Kernlänge [4T/PEN] und [6T/6P] zu wohlgeordneten Fil-men, in denen die Moleküle in gemischten Lagen parallel zur Substratoberfläche auf-wachsen und die Längsachse der Moleküle fast senkrecht zur Substratoberfläche orien-tiert ist. Molekülpaare mit ähnlicher konjugierter Kernlänge und Alkylsubstitution [6T/DH6T] und [6P/DH6T] zeigten ebenfalls geordneten Schichten, wobei als Besonderheit eine lineare Abhängigkeit des Lagenabstandes vom DH6T-Gehalt zu beobachten ist. Dies wird mit einer Phasenseparation in eine aromatische und eine alkyl Domäne erklärt. Mit abnehmendem DH6T-Gehalt im Film ist die Alkyldomäne weniger dicht gepackt, was auf Grund der Flexibilität der Alkylketten zu einer Abnahme des gesamten Lagenab-standes führt. Die besonders geringe Oberflächenrauhigkeit und die miteinander verbundenen Inseln der [DH6T/6T] Filme prädestinieren sie zur Verwendung in Feldeffekttransistoren. Es wird gezeigt, dass es möglich ist, die Ladungsträgerdichte im Kanal durch Änderung des Verhältnisses zwischen DH6T und 6T so zu verändern, dass der Transistor im Verar-mungs- oder Anreicherungsregime betrieben werden kann. Dabei bleibt die Ladungsträ-germobilität auf gleich bleibend hohem Niveau. Dies entspricht dem Dotieren eines anorganischen Halbleiters.This thesis is centered on studies of phase separation and mixing in co-deposited thin films of rod-like conjugated molecules. The main focus is to determine which molecular properties lead to phase separation and/or mixing of two materials. To address this question I used five materials, of importance in the context of “organic electronics”: pentacene (PEN), quaterthiophene (4T), sexithiophene (6T), p-sexiphenylene (6P), alpha,omega-dihexylsexithiophene (DH6T). With these it was possible to form material pairs which differ in the parameters: energy levels, length of the conjugated core, and alkyl-end-chain-substitution. All films were deposited by organic molecular beam deposition onto the chemically inert substrates silicon oxide and Mylar, a polyethylene terephthalate (PET) foil. The material pairs were deposited simultaneously from two thermal sublima-tion sources. The mixing ratio was controlled by the individual deposition rates, which were measured online by a microbalance. The total deposition rate was 0.5 nm/min, and the film thicknesses ranged from 4 nm to 40 nm. Phase separation is observed for material pairs with dissimilar conjugated core sizes, i.e. [4T/6T]. Noteworthy, the co-deposition of material pairs with similarly sized conju-gated cores [4T/PEN] and [6T/6P] lead to well ordered layered structures. The mole-cules show mixing within layers on a molecular scale and the long molecular axis is ori-ented almost perpendicular to the substrate surface. Material pairs with similarly sized conjugated core and alkyl-end-chain-substitution [6T/DH6T] and [6P/DH6T] show also growth in mixed layered structures. An especially appealing fact is that the interlayer distance increases proportional to the DH6T content in the film. This can be explained with a phase separation into an aromatic and an alkyl domain vertically to the substrate surface. A decrease of the DH6T content in the film leads to a less dense packing in the alkyl domain. This leads, due to the flexibility of the alkyl chains, to a decrease of the overall interlayer distance. The low surface corrugation and the interconnected islands render the material pair [6T/DH6T] well suitable for the use as active layer in organic field effect transistors. It is shown that it is possible to tune the charge carrier density in the channel by changing the ratio between 6T and DH6T. This effect enables switching the transistor from en-hancement to depletion mode, while maintaining a high charge carrier mobility. This is comparable to p-type doping of inorganic semiconductors.
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Giffard, Dylan. "Synthesis, radiolabelling and pharmacological evaluation of CO-releasing molecules". Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29497.
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The combatting of drug-resistant cancerous cell lines and strains of P. falciparum remain major global health problems to date, with hundreds of thousands of related deaths per annum. Early identification of solid tumours and infections, as well as the discovery of drugs with new mechanisms of action, are paramount in the fight against drug resistance. This study investigates the synthesis, characterisation and biological evaluation of new Mn(I) and Re(I) tricarbonyl metallodendrimers, in addition to the formation of a new 99mTc complex for use in diagnostic imaging. Two series of mono- and multimeric picolylamine ligands based on polyamine scaffolds were prepared. One series of ligands was functionalised with Re(I)- and Mn(I)-tricarbonyl moieties following the [2 + 1] approach, to form a series of cationic complexes. In addition, a second series of neutral bidentate (N,N) Mn(I) complexes were prepared. The ligands and complexes were characterised using a range of spectroscopic and analytical techniques, including 1H, 13C{1H}, and 31P{1H} NMR spectroscopy, infrared spectroscopy, and mass spectrometry. The stability and CO-release properties of the Mn(I) complexes were investigated using UV/Vis absorption spectroscopy. A decrease in the MLCT absorption band suggests the release of CO. CO-release was confirmed using a monomeric Mn(I) complex as a model using the myoglobin assay. The in vitro antiproliferative activity of the Re(I) complexes was investigated against three cancerous cell lines (A431, DLD-1 and A2780) and one non-tumourigenic cell line (BJ). The complexes displayed moderate to good activity, with all IC50 values in the low micromolar range. The tetranuclear complex displayed the highest efficacy against the tested cell lines (IC50 = 6 – 14 µM). Selectivity towards the cancerous cell lines was observed for the tri- and tetranuclear complexes, with higher IC50 values against the BJ cell line. The in vitro antiproliferative activity of the Mn(I) complexes was evaluated against two cancerous cell lines (A431 and A375). The tetranuclear [2 + 1] Mn(I) complex displayed the best activity against both of the tested cell lines. The [2 + 1] complexes displayed higher in vitro activity than their bidentate counterparts. The complexes were evaluated as in vitro antiplasmodial agents against chloroquine-sensitive (NF54) and chloroquine-resistant (K1) strains of P. falciparum. The [2 + 1] Mn(I) complexes displayed enhanced activity over their Re(I) analogues and their bidentate counterparts. The tetranuclear [2 + 1] Mn(I) complex displayed the best activity against the K1 strain (IC50 = 0.99 µM) and the best resistance index (RI = 0.263) of all the tested complexes. Irradiation of selected Mn(I) complexes during incubation with the K1 strain resulted in an almost two-fold increase in activity of the [2 + 1] Mn(I) complexes, but a decrease in activity of the bidentate Mn(I) complexes. Formation of the monomeric radiolabelled product was achieved by reacting 99mTc(bpy)(CO)3 with a monomeric ligand. The product was isolated using preparative HPLC, but the retention time did not match that of the Re(I) analogue, likely due to the difference in counterion. Radiolabelling of the multimeric ligands was unsuccessful.
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Kamenetzky, J., N. Rangwala, J. Glenn, P. R. Maloney y A. Conley. "L '(CO)/L-FIR RELATIONS WITH CO ROTATIONAL LADDERS OF GALAXIES ACROSS THE HERSCHEL SPIRE ARCHIVE". IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621957.
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We present a catalog of all CO (J = 4-3 through J = 13-12), [ C I], and [ N II] lines available from extragalactic spectra from the Herschel SPIRE Fourier Transform Spectrometer (FTS) archive combined with observations of the low-J CO lines from the literature and from the Arizona Radio Observatory. This work examines the relationships between L-FIR, L'(CO), and L-CO/L-CO,L-1-0. We also present a new method for estimating probability distribution functions from marginal signal-to-noise ratio Herschel FTS spectra, which takes into account the instrumental "ringing" and the resulting highly correlated nature of the spectra. The slopes of log(L-FIR) versus log (L'(CO)) are linear for all mid- to high-J CO lines and slightly sublinear if restricted to (ultra) luminous infrared galaxies ((U) LIRGs). The mid-to high-J CO luminosity relative to CO J - 1-0 increases with increasing L-FIR, indicating higher excitement of the molecular gas, although these ratios do not exceed similar to 180. For a given bin in L-FIR, the luminosities relative to CO J = 1-0 remain relatively flat from J = 6-5 through J = 13-12, across three orders of magnitude of L-FIR. A single component theoretical photodissociation region (PDR) model cannot match these flat SLED shapes, although combinations of PDR models with mechanical heating added qualitatively match the shapes, indicating the need for further comprehensive modeling of the excitation processes of warm molecular gas in nearby galaxies.
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Thielmann, Axel. "Co-tunneling current and shot noise in molecules and quantum dots". Karlsruhe : FZKA, 2005. http://bibliothek.fzk.de/zb/berichte/FZKA7167.pdf.
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Sakthivel, Priya. "Co-stimulatory molecules : genes to protein in autoimmune and inflammatory disorders /". Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-425-9/.
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Davidge, Kelly S. "Effects of Carbon Monoxide-releasing molecules (CO-RMs) on Escherichia coli". Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515442.
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Atkin, Anthony John. "Therapeutic metal (0)-containing CO- releasing molecules : mechanistic insight and bioapplications". Thesis, University of York, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556199.
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The administration of carbon monoxide (CO) to living systems has been found to elicit beneficial therapeutic responses in many different applications. In order to deliver CO safely and controllably at concentrations able to provide these positive effects, the use of carbon monoxide-releasing molecules (CO-RMs) has been developed. This thesis details the discovery of new classes of metal(O)-containing organometallic CO-RMs, their ability to release CO and their therapeutic action. Hexacarbonyl(~l2-alkyne)dicobalt(O) complexes were highlighted as potential CO- RMs. By varying the substituents on the alkyne ligand, a range of CO-release rates in aqueous media were obtained. The amount of CO released from these CO-RMs was quantified by use of a myoglobin biochemical assay. Study into the solution behaviour of these CO-RMs in DMSO/water mixtures revealed the importance of a cobalt-cobalt disproportionation reaction and also the reactivity of amino acid residues on the release rate. A selection of the hexacarbonyl(μ2-alkyne)dicobalt(O) were tested against biological systems in order to assess their therapeutic potential. Experiments with murine macrophages revealed the toxicity, the effect on the cell viability and the anti- inflammatory effect elicited by these CO-RMs. Further studies demonstrated the ability of members of this class of CO-RMs to inhibit the growth of the bacteria Pseudomonas aeruginosa. Studies on tricarbonyl(ή4-diene)iron(0) structures provided further successful CO- RMs when the diene ligand used was norbomadiene. In addition to this, tetracarbonyl(ή4-norbomadiene)chromium(O) and molybdenum(O) complexes also released CO in the myoglobin assay. Through substituent variation on the organic ligand it was found that the strength of the iron-diene bonds in the tricarbonyl(ή4- diene)iron(O) complexes was a significant factor in controlling the rate of CO-release from this class of CO-RM; complexes with weaker metal-diene bonds were generally faster CO-releasers.
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Sawle, Philip John. "Biochemical properties and bioactivities of carbon monoxide-releasing molecules (CO-RMs)". Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1445046/.
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Carbon monoxide (CO), synonymous of the "silent killer", is rapidly emerging as an important and versatile mediator of physiological processes. The study of CO has been hampered by the lack of a means to simulate its release biologically. Current means to replicate the effects of CO include, most notably, the use of CO gas and upregulation of haem oxygenase-1 (HO-1) to generate endogenous CO. Both are limited in their approach and offer only a partial solution. The recent discovery that certain transition metal carbonyls function as CO-releasing molecules (CO-RMs) in biological systems highlighted the potential of exploiting this and similar classes of compounds as a stratagem to deliver CO for research and therapeutic purposes. Initially a large portfolio of CO-RMs was investigated to determine their CO releasing capability. This thesis examines a number of aspects related to the characterisation of a core group of CO-RMs including: a) CORM-3, the prototypic water soluble transition metal carbonyl b) CORM-A1, a water soluble CO-RM without a metal centre c) CORM-319, an iron based water soluble CO-RM and d) CORM-311, an ethanol soluble iron centred CO-RM. Specifically, the study will examine CO-RMs for their ability to: i) release CO ii) suppress LPS-induced nitrite production iii) promote toxicity iv) induce haem oxygenase (HO) activity and HO-1 expression and v) modulate inducible nitric oxide synthase (iNOS) expression. These different aspects of CO-RM characterisation were addressed using biochemical, molecular biology and cell culture techniques. Further work was also carried out determining certain chemical aspects of each CO-RM including the decomposition rate and pH/temperature stability. The study into the CO release of the new CO-RMs emphasizes the versatile potential of the metal carbonyl complexes and related compounds. This research on CO-RMs will help lay the foundations for a novel therapeutic agent based on the delivery of safe and controlled quantities of CO.
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Liao, Kristine. "Calorimetry study of the adsorption of diatomic molecules on Co{110}". Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610142.
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Steinmann, C. M. (Christine Margarete). "Vacuum ultraviolet laser spectroscopy of CO molecules in a supersonic jet". Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53709.
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Thesis (PhD)--Stellenbosch University, 2003.ENGLISH ABSTRACT: A tunable narrow-bandwidth laser source combined with a supersonic gas jet as sample is wellsuited for obtaining high-resolution spectra of cold isolated molecules and complexes. In the present study such a laser source in the vacuum ultraviolet was applied to the spectroscopic investigation of rare carbon monoxide (CO) isotopomers and CO-noble gas van der Waals complexes in supersonic gas pulses seeded with natural CO gas. Tunable coherent vacuum ultraviolet radiation was generated by two-photon resonant fourwave sum-frequency mixing of two pulsed dye laser beams in a magnesium vapour medium. Laser induced fluorescence excitation spectra of the A(v'=3)-X(v"=0) vibronic band of CO molecules in a noble gas (neon or argon) jet were obtained by measuring the total undispersed fluorescence from the irradiated sample volume in dependence of the excitation wavelength. The dynamics of the flow-cooling process in the supersonic jet were investigated and the experimental parameters optimised using the rotational temperature of 12C160as determined from rotational line intensities. Rotational temperatures as low as 2 ± I K were observed. Spectroscopic detection of the rare 12C170and 12C180isotopomers was facilitated by the low rotational temperature and high spectral resolution. Six rotational lines of 12C170and four of 12C180were detected in the A(v'=3)-X(v"=0) vibronic band. This demonstrates the low detection limit (circa 3 parts per million) obtained in the experiment. The line wavelengths were determined to an accuracy of 0.2 pm using the well-documented 12C160and 13C160lines for calibration. The spectral results on 12C170are, to our knowledge, the first rotationally resolved laboratory measurements published on the A-X band of this isotopomer. Accurate wavelength data of the stable isotopomers of CO is of importance in the interpretation of astrophysical observations of CO in the interstellar medium. The newly determined 12C170wavelengths were successfully applied to a recent problem in astrophysics (Astrophys. J. Lett. 2003). The conditions in a supersonic jet facilitate the study of weakly bound van der Waals complexes, of which CO-noble gas complexes are prototypes. However, there is no experimental data available on the electronic excitation spectra of the CO-noble gas complexes, lying in the vacuum ultraviolet region. In the present experiment evidence of extensive complexation of the CO in the noble gas jet has been found, but in the spectral region around the A(v'=3)-X(v"=O) band of CO no distinct spectral features that could be associated with these complexes were observed. Having considered the existing knowledge on CO and CO-noble gas complexes and experimental studies on the excitation and dissociation dynamics of Iz-noble gas complexes, we regard complex induced inter-system crossing or electronic predissociation as the most likely causes for these observations. The results on the rare CO isotopomers demonstrate the potential of our experimental setup for high-resolution, isotope and state selective spectroscopy in the vacuum ultraviolet with a high sensitivity for fluorescent species. The availability of the now well-characterised experimental setup in our laboratory opens the way for further investigation of molecular or complex species with spectroscopic features in the vacuum ultraviolet region.
AFRIKAANSE OPSOMMING: Vakuum ultraviolet laser spektroskopie van CO molekules in 'n supersoniese gasstraal: 'n Afstembare smal bandwydte laserbron en 'n supersoniese gasstraal as monster is 'n geskikte kombinasie vir hoë-resolusie spektroskopie van geïsoleerde afgekoelde molekules en komplekse. In hierdie studie is so 'n laserbron in die vakuum ultraviolet gebruik in die spektroskopiese ondersoek van skaars koolstofmonoksied (CO) isotopomere en CO-edelgas van der Waals komplekse in supersoniese gaspulse wat 'n klein persentasie natuurlike CO gas bevat. Afstembare koherente vakuum ultraviolet lig is verkry deur twee-foton resonante vier-golf som-frekwensie vermenging van twee gepulseerde kleurstoflaserbundels in 'n magnesiumdamp medium. Laser-geïnduseerde fluoressensie opwekkingspektra van die A(v'=3)-X(v"=0) vibroniese band van die CO molekules in die edelgasstraal (neon of argon) is uitgemeet deur die totale fluoressensie van die beligte gasmonster, sonder golflengteskeiding, te meet as funksie van die opwekkingsgolflengte. Die dinamika van die vloeiverkoelingsproses in die supersoniese gasstraal is ondersoek en die eksperimentele parameters geoptimeer deur gebruik te maak van die rotasionele temperatuur van 12Cl60 soos bepaal uit die intensiteitsverhoudings van die rotasielyne. Rotasionele temperature tot so laag as 2 ± 1 K is waargeneem. Spektroskopiese waarneming van die skaars 12C170 and 12Cl80 isotopomere is moontlik gemaak deur die lae rotasionele temperatuur en die hoë spektrale resolusie. Ses rotasielyne van 12C170 en vier van 12C180 is waargeneem in die A(v'=3)-X(v"=0) vibroniese band. Dit demonstreer die lae deteksielimiet (ongeveer 3 dele per miljoen) wat bereik kon word. Die golflengtes van die lyne is bepaal met 'n akkuraatheid van 0.2 pm deur die bekende lyne van 12C160en 13C160vir kalibrasie te gebruik. Die resultate ten opsigte van 12C170 is sover vasgestel kon word die eerste rotasioneel-opgeloste laboratorium metings van die A-X band van hierdie isotopomeer. Akkurate golflengte data vir die stabiele CO isotopomere is van belang vir die interpretasie van die astrofisiese waarnemings van CO in die interstellêre medium. Die nuwe 12C170 golflengtes is suksesvol aangewend in die oplossing van 'n onlangse interpretasieprobleem in astrofisika (Astrophys. J. Lett. 2003). Die toestande in 'n supersoniese gasstraal maak die bestudering van swak-gebonde van der Waals komplekse moontlik. Hoewel CO-edelgas van der Waals komplekse as prototipes beskou word, is daar geen eksperimentele data beskikbaar oor die elektroniese opwekkingspektra van hierdie spesies, wat in die vakuum ultraviolet gebied lê, nie. In hierdie studie is daar eksperimentele getuienis gevind vir uitgebreide kompleksering van CO in die edelgasstraal, maar in die spektraalgebied rondom die A(v'=3)-X(v"=O) band van CO is geen duidelike spektrale kenmerke wat met hierdie komplekse geassosieer kan word, waargeneem nie. Na oorweging van die bestaande kennins oor CO en CO-edelgas komplekse en eksperimentele studies oor die opwekking en dissosiasie-dinamika van Iz-edelgas komplekse, beskou ons kompleksgeïnduseerde intersisteemoorgange of elektroniese predissosiasie as die waarskynlikste redes vir hierdie waarnemings. Die resultate oor die skaars CO isotopomere toon die potensiaal van ons eksperimentele opstelling vir hoë-resolusie, isotoop- en toestandselektiewe spektroskopie in die vakuum ultraviolet met uitstekende sensitiwiteit vir fluoresserende spesies. Die beskikbaarheid van hierdie nou deeglik gekarakteriseerde eksperimentele opstelling in ons laboratorium maak verdere ondersoek na molekulêre of kompleks-spesies met spektroskopiese kenmerke in die vakuum ultraviolet moontlik.
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Bieging, John H., Saahil Patel, William L. Peters, L. Viktor Toth, Gábor Marton y Sarolta Zahorecz. "THE ARIZONA RADIO OBSERVATORY CO MAPPING SURVEY OF GALACTIC MOLECULAR CLOUDS. V. THE SH2-235 CLOUD IN CO J = 2 − 1, 13 CO J = 2 − 1, AND CO J = 3 − 2". IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621984.
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We present the results of a program to map the Sh2-235 molecular cloud complex in the CO and (CO)-C-13 J = 2 - 1 transitions using the Heinrich Hertz Submillimeter Telescope. The map resolution is 38 '' (FWHM), with an rms noise of 0.12K brightness temperature, for a velocity resolution of 0.34 km s(-1). With the same telescope, we also mapped the CO J = 3 - 2 line at a frequency of 345 GHz, using a 64 beam focal plane array of heterodyne mixers, achieving a typical rms noise of 0.5 K brightness temperature with a velocity resolution of 0.23 km s(-1). The three spectral line data cubes are available for download. Much of the cloud appears to be slightly sub-thermally excited in the J = 3 level, except for in the vicinity of the warmest and highest column density areas, which are currently forming stars. Using the CO and (CO)-C-13. J = 2 - 1 lines, we employ an LTE model to derive the gas column density over the entire mapped region. Examining a 125 pc(2). region centered on the most active star formation in the vicinity of Sh2-235, we find that the young stellar object surface density scales as approximately the 1.6-power of the gas column density. The area distribution function of the gas is a steeply declining exponential function of gas column density. Comparison of the morphology of ionized and molecular gas suggests that the cloud is being substantially disrupted by expansion of the H II regions, which may be triggering current star formation.
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Popova, Marina. "Visible Light-Triggered Carbon Monoxide-Releasing Molecules". DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7500.
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Carbon monoxide (CO) is now well established as one of the signaling molecules in higher organisms, including humans. Due to its physiological roles, CO is now accepted as a potential therapeutic agent. The use of CO gas has been studied in multiple clinical trials. Vasodilation, anti-inflammatory, anti-apoptotic, anti-proliferative and cytoprotective effects are just a few of the pharmacological actions attributed to CO gas in various models of diseases. Use of inhaled CO gas as a therapeutic has many limitations which necessitate the development of a new approach for CO delivery. In order to handle CO safely, compounds that release CO (CO-releasing molecules, CORMs) have been developed. CORMs that release CO only when triggered, and with the ability to target certain tissue sites, are of particular interest. Our lab is developing molecules that release CO only when illuminated with visible light (photoCORMs). These photoCORMs are based on a motif found in naturally-occurring flavonols, which are chemical compounds found in wide variety of foods including fruits, vegetables, tea and dark chocolate.
The research presented in this dissertation outlines the results of studies on extended flavonols as CO release agents. The specific studies described herein focus on understanding visible light-induced CO-releasing flavonols in terms of their: a) structure/reactivity relationships, especially in biological environments; b) interactions with metal ions and proteins; c) reaction pathway of CO release; and d) their properties when combined with a CO-sensing motif.
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Teleshova, Natalia. "Studies on co-stimulatory molecules, chemokines and chemokine receptors in neuroimmunological diseases /". Stockholm, 2001. http://diss.kib.ki.se/2001/91-628-4781-3/.
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Sala, Andrea. "Supramolecular derivatisation of bioactive molecules via co-crystallization and cyclodextrin inclusion complexation". Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29711.
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The objective of this study was to modify the physicochemical properties of two common drugs via supramolecular derivatization. Sulfasalazine is a powerful anti-inflammatory drug and fluconazole has a strong antibacterial and antifungal activity. The common feature is their very low solubility in water. Cyclodextrin inclusion complexation and co-crystallization were carried out with the aim of ultimately improving the bioavailability of both drugs. Each new crystal phase isolated was analysed using X-ray diffraction, thermal and spectroscopic techniques. Sulfasalazine presents two tautomeric forms which were isolated using different preparative methods via recrystallization from different solvents. Each form was used in combination with nine different co-formers in attempts to form co-crystals. This approach yielded negative results. Cyclodextrin inclusion complexation of sulfasalazine was studied with a variety of cyclodextrins (αCD, β-CD, γ-CD, dimethylated β-CD and permethylated β-CD). The complexation attempts yielded an inclusion complex between one of the tautomers of sulfasalazine and γ-cyclodextrin. No single crystals were obtained and hence it was impossible to resolve the crystal structure. However, it was possible to analyse the complex thermally and spectroscopically. The co-crystallization of fluconazole with biocompatible co-formers was not investigated due to the appearance of extensive previous reports on its co-crystal formation in the literature. Thus, only cyclodextrin inclusion complexation (with the same CDs listed above) was studied. Three inclusion complexes with native CDs were successfully prepared. Two crystallographically distinct complexes of β-CD with fluconazole as guest having 2:1 host-guest stoichiometry were isolated. While these two hydrated complexes had been identified recently by previous researchers and the X-ray structure of one of the crystal forms had been partially resolved, their characterization was incomplete. In the present study, significant advances on the previous work included the complete X-ray structural resolution of both crystal forms, designated TBCDFLU (triclinic) and MBCDFLU (monoclinic), as well as a systematic study of the conditions under which these individual forms could be isolated. The occurrence of these crystal forms was dependent on two variables, namely β-CD concentration in the aqueous mother liquor and the incubation temperature of the solution. Careful examination of the sensitive crystallization equilibrium indicated that, at a solution concentration of 6.52 10-2 M, pure TBCDFLU could be isolated at an incubation temperature of 45 C or lower, while pure MBCDFLU crystallized at an incubation temperature of 60 C (for both cases the incubation period is more than 48 h). MBCDFLU and TBCDFLU crystals displayed different stabilities with respect to dehydration when exposed to air and hence determination of their respective water contents was performed using thermogravimetry on fresh crystals immersed in silicone oil. From a phase solubility study, it was established that the association constant for complex formation between - CD and fluconazole in solution was very low (27.2 M-1), implying weak host-guest binding. Finally, a 1:1 inclusion complex between -CD and fluconazole was isolated and characterized by thermal and spectroscopic techniques.
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Grönkvist, Stefan. "All CO2 molecules are equal, but some CO2 molecules are more equal than others". Doctoral thesis, KTH, Energiprocesser, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-452.
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This thesis deals with some challenges related to the mitigation of climate change and the overall aim is to present and assess different possibilities for the mitigation of climate change by: • Suggesting some measures with a potential to abate net greenhouse gas (GHG) emissions, • Discussing ideas for how decision-makers could tackle some of the encountered obstacles linked to these measures, and • Pointing at some problems with the current Kyoto framework and suggesting modifications of it. The quantification of the net CO2 effect from a specific project, frequently referred to as emissions accounting, is an important tool to evaluate projects and strategies for mitigating climate change. This thesis discusses different emissions accounting methods. It is concluded that no single method ought to be used for generalisation purposes, as many factors may affect the real outcome for different projects. The estimated outcome is extremely dependent on the method chosen and, thus, the suggested approach is to apply a broader perspective than the use of a particular method for strategic decisions. The risk of losing the integrity of the Kyoto Protocol when over-simplified emissions accounting methods are applied for the quantification of emission credits that can be obtained by a country with binding emissions targets for projects executed in a country without binding emission targets is also discussed. Driving forces and obstacles with regard to energy-related co-operations between industries and district heating companies have been studied since they may potentially reduce net GHG emissions. The main conclusion is that favourable techno-economic circumstances are not sufficient for the implementation of a co-operation; other factors like people with the true ambition to co-operate are also necessary. How oxy-fuel combustion for CO2 capture and storage (CCS) purposes may be much more efficiently utilised together with some industrial processes than with power production processes is also discussed. As cost efficiency is relevant for the Kyoto framework, this thesis suggests that CCS performed on CO2 from biomass should be allowed to play on a level playing field with CCS from fossil sources, as the outcome for the atmosphere is independent of the origin of the CO2.QC 20101015
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Lim, Wilfred Tan. "Molecular mechanisms in the regulation of B7-1 and B7-2 co-stimulatory molecules in human monocytic cells". Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/29357.
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The engagement of CD28 receptor with the B7-1 or B7-2 ligands on antigen presenting cells, provide the critical second co-stimulatory signal for the immune activation of T lymphocytes. The molecular mechanisms by' which B7-1 or B7-2 expressions are regulated are not well understood.
I investigated the role of mitogen-activated protein (MAPKs) in the regulation of lipopolysaccharide (LPS)-induced B7-1 expression in human monocytes and the promonocytic THP-1 cells. My results show that LPS-induced B7-1 expression in monocytic cells did not involve the activation of either p38 or ERK kinases. By employing JNK inhibitors SP600125, dexamethasone and curcumin that inhibit JNK activation, LPS-induced B7-1 expression was determined to be regulated by JNK MAPKs in both monocytes and THP-1 cells. Also, I identified a distinct B7-1 regulatory element corresponding to the interferon regulatory factor-7 (IRF-7) binding site on the B7-1 promoter, responsible for the regulation of LPS-induced B7-1 transcription. Furthermore, SP600125 and dexamethasone inhibited LPS-induced IRF-7 activity as determined by the luciferase reporter and gel shift assays. Taken together, the results suggest that LPS-induced B7-1 transcription in human monocytic cells may be regulated by IRF-7 transcription factor through JNK MAPKs activation.
I also studied the role of MAP kinases in the regulation of B7-2 expression in LPS stimulated human monocytic cells. LPS stimulation of human monocytes resulted in the down-regulation of B7-2 expression that could be abrogated by anti-IL-10 antibodies. My results reveal the distinct involvement of p38 in IL-10 dependent, and JNK in 1L-10independent regulation of B7-2 expression in LPS-stimulated monocytic cells. In addition, by deletion and mutant B7-2 promoter/luciferase gene analysis I identified 3 positive regulatory elements on the B7-2 promoter, NF-kappaB, IRF-2, and an unidentified binding site region that operate cooperatively to control B7-2 expression.
Elucidating the signal pathway and molecular mechanisms in the regulation of B7-1 and B7-2 in antigen presenting cells is important as it could provide us with a better understanding of the molecular basis for CD28/B7 co-stimulation. This in turn, may lead to the development of strategies in treating autoimmune diseases, organ transplantation rejections, graft-versus-host disease, infections, and cancer.
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Puff, David. "The use of mass spectrometry for the characterization of molecules co-purifying with integrins". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/MQ53211.pdf.
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Hammad, Jehad H. A. "The effects of water-soluble carbon monoxide-releasing molecules (CO-RMs) on vascular tone". Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444729/.
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Carbon monoxide (CO) is an important signalling messenger in mammalian cells as it participates in a variety of physiological processes including vessel tone regulation. Dr. Motterlini's group has discovered a new class of molecules which have the ability to carry and deliver CO to physiological systems. These molecules were termed CO-releasing molecules (CO-RMs) and they are an excellent tool to investigate the biological role of CO in the vasculature and other systems. The major focus of the research presented in this report was to evaluate the effects of different water soluble CO-RMs on vascular tone. For this purpose, an aortic ring preparation model was used to assess the vasodilatory properties of CORM-3 and CORM-A1, the first two water-soluble CO-RMs to be identified, and the cellular targets involved in this effect. CORM-3 is a transition metal carbonyl that liberates CO very rapidly (1=1-5 min) in physiological solutions, whereas CORM-A1 is a boron-containing carbonate with a much slower rate of CO release (tvi=21 min at pH=7.4). In the current studies CORM-3 induced a rapid endothelium-dependent vasorelaxation, whereas CORM-A1 elicited gradual endothelium-independent vasorelaxation. The inactive form of both CO-RMs, in which CO has been deliberately depleted, did not exert vasorelaxation indicating a direct involvement of CO liberated from the compounds in the observed vasorelaxation. The vasorelaxation induced by both molecules was enhanced and attenuated by an activator and inhibitor of guanylate cyclase (sGC), respectively. CORM-3-mediated vasorelaxation was completely abolished by non-selective inhibitors of potassium channels (K+), and partially attenuated by inhibition of ATP dependant (Katp) potassium channels. In contrast, CORM-A1 -mediated vasorelaxation was partially attenuated by non selective inhibition of K+ and by inhibition of voltage dependent (Ky) potassium channels. Even at concentrations higher than that used to induce significant vasorelaxation, both CO-RMs had no noticeable effect on the viability of rat aortic smooth muscle cells (A7r5) in vitro. CORM-319, a new water soluble iron containing CO-RM, also induced significant vasorelaxation and was relatively safe to cultured SMCs compared to other non-water soluble iron containing CO-RMs that were extremely toxic. In summary, our data reveal that the CO-RMs examined in this project are promising CO carriers that could be further modified for optimal therapeutic applications. In addition, our data demonstrate the significant effect imposed by the chemical structure and kinetics of CO release on the pharmacological activity of various CO-RMs.
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Ozanne, Daniel M. "Isolation and characterisation of co-regulatory molecules involved in androgen receptor movement and transactivation". Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327237.
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Ledger, Araminta. "Chelating phosphine complexes of ruthenium for the co-ordination and activation of small molecules". Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.545330.
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Golibrzuch, Kai. "Quantum-state specific scattering of molecules from surfaces". Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-9904-3.
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Zhai, Yuxin. "Spectroscopic Studies of Adsorbed CO2 on Polyamines and Photo-generated Electrons in Photocatalytic Synthesis". University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1538145926835136.
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Berends, Hans-Martin [Verfasser]. "Manganese compounds as catalysts for water oxidation and as CO releasing molecules / Hans-Martin Berends". Kiel : Universitätsbibliothek Kiel, 2011. http://d-nb.info/1020244836/34.
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Gwyer, Emily. "Parameters affecting the expression and function of late co-stimulatory molecules in health and disease". Thesis, Imperial College London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503780.
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Li, Jin. "Bone morphogenetic proteins and their co-receptor, repulsive guidance molecules, signalling pathways in human cancers". Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55075/.
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RGMs (repulsive guidance molecules) are a group of recently identified GPI (glycosylphosphatidylinositol)-linked cell-membrane-associated proteins, comprising three family members, which have been implicated in BMPs (Bone morphogenetic proteins) signalling. BMPs have been shown to play profound roles in bone metastases from breast cancer and prostate cancer. This study aims to investigate the implication of RGMs in prostate cancer and breast cancer and their role in coordinating signal transduction by BMPs during disease progression of cancer. The aberrant expression of RGMs was found in breast cancer which was associated with prognosis of breast cancer patients. RGMA, B and C were detected in prostate cancer cell lines and only RGMB was expressed in breast cancer cell lines which allowed for the knockdown study of RGMs in PC-3 and RGMB in MDA-MB-231 using ribozyme transgenes. The knockdown of RGMB in breast cancer cells resulted in an increase of cellular proliferation, adhesion, motility and migration in vitro, which contributed to a tumour's growth and metastasis. Furthermore, an inhibition of caspase-3 was seen in cells after knockdown of RGMB which indicated RGMB as a regulator of cell survival. Up-regulation of FAK and Paxillin were also seen in the cancer cells after loss of RGMB expression, together with an evident induction of EMT (epithelial-mesenchymal transition) which may contribute to the promoted cell-matrix adhesion and cell mobility. The knockdown of RGMs in prostate cancer cells also lead to an increase of cell ability to grow, adhere and move, in which differentiated response of ID-1, a BMPs target gene was seen. As RGMs were reported to be involved in BMP signalling, knockdown of RGMB was found to induce promotion on Smad-dependent pathways (especially Smad-1/5/8 pathway) and inhibition on BMP Smad-independent pathways (MAPK JNK pathway). It suggests that RGMs are important partners to fine-tune responses of cells to BMPs stimuli, particularly during the progression and dissemination of cancer cells, and are potential targets for developing a novel cancer therapy.
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Wang, Yiting. "Syntheses, Crystal Structures and Characterizations of Mono- and Polynuclear Ni- and Co-based Molecular Magnets". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS225.
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L’objectif consistant à élaborer des «aimants par conception» peut être atteint en adaptant les structures moléculaires des complexes de coordination. Les molécules conçues devraient présenter les caractéristiques requises pour des applications spécifiques, qui résultent de leur riche diversité structurale. Des complexes mononucléaires à base de Ni avec une grande anisotropie magnétique et des molécules polynucléaires à base de Ni et de Co sont préparés et étudiés dans cette thèse. Les synthèses, les études magnétiques et les propriétés électrochimiques des complexes contenant un ligand pontant non innocent sont étudiées. Les complexes mononucléaires Ni(II) à géométrie bipyramide trigonale sont préparés avec des ligands axiaux et les contre-anions différents. L'effet de la nature des ligands axiaux et du changement structural induit par les contre-anions sur l'anisotropie magnétique est étudié expérimentalement et analysé à l'aide de calculs théoriques. Des molécules organiques sont utilisées pour concevoir des complexes trinucléaires à grande anisotropie magnétique et à couplage d'échange faible. Plusieurs complexes polynucléaires à base de Ni et de Co où le TTC³⁻ agit comme un ligand pontant innocent et le HHTP³⁻ comme un ligand non innocent typique sont cristallisés avec diverses structures (TTC = Trithiocyanurate; HHTP = Hexahydroxytriphénylène). Pour les complexes contenant le ligand non innocent (HHTP), les anions radicalaires sont produits par électrochimie. La combinaison de la spectro-électrochimie et de la spectroscopie à résonance paramagnétique électronique couplée à des études d'électrochimie permet d'étudier la délocalisation des électrons sur les radicaux organiques générés et le couplage d'échange entre les ions métalliquesThe objective of elaborating “magnets by design” can be achieved by tailoring the molecular structures of coordination complexes. The designed molecules are expected to exhibit the characteristics required for specific applications, virtually resulting from their rich structural diversity. Mononuclear Ni-based complexes with large magnetic anisotropy and polynuclear Ni- and Co-based molecules are designed in this dissertation. The syntheses, magnetic studies, and electrochemical properties of the complexes containing non-innocent bridge ligand are investigated. The Ni(II) mononuclear complexes with trigonal bipyramid geometry are prepared by tuning the axial ligands and the counter anions. The effect of the nature of the axial ligands and the structural change induces by the counter anions on magnetic anisotropy is studied experimentally and analyzed with the help of theoretical calculations. Large organic molecules are used to design trinuclear complexes with large magnetic anisotropy and weak exchange coupling. Several polynuclear Ni- and Co-based complexes with TTC³⁻ acting as an innocent bridging ligand and HHTP as a typical non-innocent ligand, are crystallized with various structures (TTC = Trithiocyanurate; HHTP = Hexahydroxytriphenylene). For the complexes containing the non-innocent ligand (HHTP), radical anions are produced by electrochemistry. The combination of spectroelectrochemical and Electron Paramagnetic Spectroscopy coupled to electrochemistry studies allow investigating the delocalization of the electrons on the generated organic radicals and the exchange coupling among the metal ions
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Jazzazi, Taghreed [Verfasser], Matthias [Akademischer Betreuer] Westerhausen y Rainer [Akademischer Betreuer] Beckert. "CO-Sources for the liberation of cellular messenger molecules / Taghreed Jazzazi. Gutachter: Matthias Westerhausen ; Rainer Beckert". Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2013. http://d-nb.info/1041255837/34.
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Sandouka, Ashraf. "Carbon monoxide-releasing molecules (CO-RMs) : effects on physiology and ischaemia-reperfusion injury in the kidney". Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1445042/.
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Background: Although high concentrations of carbon monoxide (CO) are unquestionably toxic, emerging evidence reveals that CO at low concentrations plays a significant role in vasorelaxation, blockade of apoptotic pathways, suppression of inflammation and protection against ischaemia-reperfusion (I-R) injury. Our group has recently identified a series of compounds (CO-releasing molecules or CO-RMs) which exert important pharmacological activities by carrying and delivering CO to biological systems.;Aims: The present study was designed to evaluate the influence of CO released from CO-RMs on mitochondrial respiration and its consequences on renal haemodynamic, biochemical, and physiological parameters as well as to examine the possible beneficial effects of CO-RMs against I-R injury.;Methods: Parallel experiments were conducted using: 1) the isolated renal cortical rat mitochondria for evaluation of oxygen consumption, hydrogen peroxide production, and lipid peroxidation. 2) the ex vivo isolated perfused rabbit kidney (IPRK) model to measure the physiological and biochemical parameters and mitochondrial respiration for freshly harvested kidneys and kidneys exposed to ischaemic injury, and 3) an in vitro model of renal proximal tubular epithelial (LLC-PKi) cells to assess membrane integrity and metabolic activity.;Results: The major findings of this study indicate that CO modulates mitochondrial respiratory activity in isolated rat mitochondria. In IPRK model, CO reduces tubular reabsorption and increases urine and perfusion flow rate and glomerular filtration rate of freshly isolated kidneys. However, in IPRK model, kidneys flushed with a cold preservation solution supplemented with CO-RMs and stored at 4 C for 24 or 48 hr displayed at reperfusion a significant protective vasodilatory effect, improved renal function and mitochondrial respiration compared to control kidneys flushed with cold solution alone. Additionally, CO released from CO-RMs protects against preservation injury using the in vitro model of LLC-PKi cells. In contrast, in a warm I-R model using the IPRK circuit, CO was only beneficial by increasing the perfusate flow rate at reperfusion.;Conclusion: the results emphasize that CO liberated from CO-RMs has a protective vasodilatory effect, improves renal function and increases mitochondrial respiration after cold ischaemia and reperfusion. These findings suggest that CO-RMs could be used therapeutically in preservation solutions as an efficacious strategy to prevent the injury sustained by organs during cold storage prior to transplantation.
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Mohmand, Ghulam Farouq. "Synthesis and co-ordination chemistry of a new class of macrocyclic thioether molecules containing acetylenic functionalities". Thesis, University of Kent, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282428.
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Roth, Patrick [Verfasser] y Ulrich [Gutachter] Schatzschneider. "Metalltricarbonyl-basierte CO-releasing molecules (CORMs): Variation der Freisetzungskinetik und Biokonjugation / Patrick Roth ; Gutachter: Ulrich Schatzschneider". Würzburg : Universität Würzburg, 2021. http://d-nb.info/1236547950/34.
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Esposito, Federico. "Interpreting the CO SLED with starburst and AGN feedback". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14102/.
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Il presente lavoro di tesi si basa sullo spettro rotazionale del monossido di carbonio (CO) di 4 galassie locali, e lo interpreta sulla base della densità del mezzo molecolare responsabile dell'emissione e del tipo di sorgente radiativa che eccita tale molecola. Due
tipi di sorgente sono stati considerati: popolazioni stellari giovani (modello PDR) e AGN (modello XDR). La CO SLED è stata ricavata principalmente da osservazioni del satellite infrarosso Herschel. Per le 4 galassie studiate (IRAS F05189-2524, NGC 34, NGC 4418 e NGC 6240) sono state prodotte le mappe spazialmente risolte dell'emissione del CO delle osservazioni ALMA. Questo ci ha permesso di stabilire un'area fisica all'interno delle galassie entro cui il gas molecolare è presente ed emette radiazione. Con il codice di sintesi spettrale Cloudy (Ferland et al. 2013) abbiamo preparato due griglie di simulazioni per i modelli PDR e XDR. I risultati di queste simulazioni sono stati combinati nei modelli finali, composti di due PDRs o di una PDR ed una XDR; la CO SLED simulata è stata quindi comparata a quella osservata tramite una procedura di minimizzazione. I risultati ottenuti sono i seguenti: per due galassie (NGC 34 e NGC 6240) il modello di best-fit è quello a doppia PDR, per le altre due (IRAS F05189-2524 e NGC 4418) è il PDR + XDR. I risultati riguardanti NGC 4418 vanno considerati con cautela in quanto il codice di minimizzazione non è riuscito a trovare un buon fit della CO SLED. I 4 oggetti selezionati non sembrano in generale dominati dalla presenza delle XDRs per quanto riguarda l'eccitazione del gas molecolare, da cui si conclude che il contributo dell'AGN (osservato in tutte tranne che in NGC 4418) nel determinare la fisica del gas interstellare non è dominante. Dai modelli di best-fit sono state ricavate le masse di gas, e da queste sono stati calcolati i fattori di conversione del CO e i depletion times. Tali grandezze sono state confrontate con galassie presenti in letteratura.
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Ratnayake, Upul Nishantha. "Polypropylene-clay nanocomposites : effects of incorporating short chain amide molecules on rheological and mechanical properties". Thesis, Loughborough University, 2006. https://dspace.lboro.ac.uk/2134/11600.
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The influence of low molecular weight additives containing polar groups and modified polyolefin-based compatibilisers on polypropylene (PP)-clay nanocomposites (PPCN) has been studied, in terms of intercalation and degree of exfoliation achievable by melt state mixing processes. PPCN were prepared by melt mixing of two commercial pp homopolymers with organically modified clay (OMMT) in the presence of maleic anhydride grafted pp (PP-MA). X-ray diffraction (XRD) analysis shows that the interlayer spacing of clay increases dramatically, whilst transmission electron microscopy (TEM) results show a significant improvement of clay dispersion in the PP matrix, when nanocomposites are prepared with commercial PP containing short chain organic additives with polar groups (amide-type slip and antistatic additives). Subsequent studies based upon customised PP formulations, with short chain amide molecules (AM), confirm the intercalation of this additive into clay galleries. The maximum interiayer spacing is achieved with low concentrations of this additive (0.5 wt. %). Contact angle measurements and low shear melt flow properties (MF!) further confirm the diffusion of this additive (AM) into the clay galleries rather than migrating away from the bulk of the PPCN. The interaction between the polar group (CONH2) of this additive and polar sites of the clay surface appears to be the driving force for the intercalation. Although this additive intercalates and allows the formation of an intercalated nanocomposite structure with non homogeneous dispersion of clay, an exfoliated PPCN structure is yet to be formed with this additive alone. A new preparation method for PPCN has therefore been developed by co-intercalation of AM and PP-MA. PPCN were prepared by this method with a significant reduction of overall PP-MA concentration in the nanocomposite structure, relative to conventional PPCN prepared with compatibiliser (PP-MA) only. XRD and TEM analysis showed that nanocomposite structures are formed with significantly improved clay dispersion, compared to PPCN prepared using the conventional method. Quantification of clay exfoliation, using image analysis software, showed that higher degrees of exfoliation can be achieved in PPCN from this new cointercalation method. Normalised melt flow index (n-MFI) data showed the relationship between low shear flow properties and clay structure and is an appropriate parameter to examine clay exfoliation and its interaction with pp in PPCN. Enhanced thennal stability of PPCN, in comparison to pure PP, further demonstrates the improved clay dispersion in nanocomposite structures prepared by the co-intercalation method. A possible mechanism for the co-intercalation of AM and PP-MA into clay galleries has been proposed, based upon hydrogen bonding between these additives and the silicate layers. Rheological characterisation of PPCN, using capillary rheometry experiments at high shear rates, shows a shear thinning, pseudoplastic behaviour similar to pure PP. However, a comparatively higher concentration of AM appears to reduce the shear viscosity of PPCN. Die swelling behaviour revealed a reduction in melt elasticity in PPCN melts in comparison to unmodified PP. Reduced die swell occurs as a result, together with a delay in the onset of melt fracture. Sheet extrusion was used to produce PPCN products with increasing clay loading levels that were evaluated for a range of mechanical properties. Significant enhancement of modulus in PPCN is achieved in comparison to pure PP whilst maintaining similar strength characteristics. However, impact resistance of extruded PPCN sheets is not improved in comparison to unmodified PP. Results have been interpreted with reference to the degree of exfoliation, additive content and differences in PP crystallinity.
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Thielmann, Axel [Verfasser]. "Co-tunneling current and shot noise in molecules and quantum dots / Forschungszentrum Karlsruhe GmbH, Karlsruhe. Axel Thielmann". Karlsruhe : FZKA, 2005. http://d-nb.info/977173488/34.
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Singh, Baljit. "The role of co-stimulatory molecules and inflammatory cytokines in a murine model of inflammatory bowel disease". Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275392.
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Handa, Tomohiro. "Gene polymorphisms co-stimulatory molecules (CTLA-4 and B7) : association with clinical manifestations in patients with sarcoidosis". Kyoto University, 2006. http://hdl.handle.net/2433/143829.
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Musarneh, Muntaser Darwish Mustafa. "The Effects of Carbon Monoxide Releasing Molecules (CO-RMS) in Myocardial Inotropy and Protection Against Ischaemia-Reperfusion Injury". Thesis, University College London (University of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487768.
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Myocardial ischaemia reperfusion injury is common in clinical prac.tice. Myocardial infarction is a good example, in which prolonged coronary artery occlusion by a thrombus may be followed by reperfusion either spontaneously or by medical intervention with thrombolytic drugs or acute angioplasty. The heart may also undergo ischaemia-reperfusion during operations that require temporary interruption of myocardial blood supply s~ch as, coronary artery bypass grafting and heart transplantation. Carbon monoxide, one of the products of haem degradation by the enzyme haem oxygenase, has been shown to protect the myocardium against reperfusion injury and confer other desirable effects despite the bad historical reputation it always had (the silent killer and waste product). Special molecules (COtRMs) capable of carrying carbon monoxide and releasing it in physiological solution have been developed to facilitate further investigation of the role of this gas in biosystems under physiological and pathological conditions and to provide the basis for potential therapeutic agent in the future. The aims of this study are to examine: 1) the effects of CO-RMs on hearts perfused under normal physiologic conditions; 2) the mechanism of the positive inotropic effect induced by some CORMs; 3) to test CO positive inotropic action in failing rat hearts; 4) to study the ability of CO-RMs these molecules to protect against ischaemia-reperfusion injury in models resembling myocardial infarction and heart cold preservation. Results demonstrated for the first time that CO-RM possess positive inotropic effects, and that protection was afforded by the drug against myocardial IIR.
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Samanta, Susruta [Verfasser]. "Theoretical Study of the Interaction of Amphiphilic Block Co-Polymers with Biological Interfaces and Small Molecules / Susruta Samanta". Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2013. http://d-nb.info/1037011961/34.
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Rowley, Tania Francesca. "Functional analysis of the co-stimulatory molecules CD27 and CD137 (4-1BB) during T cell-mediated immune responses". Thesis, University of Southampton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418040.
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Vicentini, Michelle Alves. "Efeito modulatório da coinfecção pelo Mycobacterium bovis na resposta imunológica de camundongos infectados com Strongyloides venezuelensis". Universidade Federal de Juiz de Fora (UFJF), 2008. https://repositorio.ufjf.br/jspui/handle/ufjf/2831.
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FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais
As parasitoses intestinais representam um importante problema médico-sanitário, tendo em vista o grande número de pessoas acometidas e as inúmeras alterações orgânicas que podem provocar no hospedeiro. Infecções provocadas por Strongyloides venezuelensis apresentam uma resposta imune local tanto nos pulmões quanto no intestino, predominantemente do tipo Th2, caracterizada pela produção das citocinas IL-4, IL-5, IL-13 e IL-10, resultando em eosinofilia, aumento da produção de muco, mastocitose e altas concentrações de IgE. Por outro lado, infecções provocadas por micobactérias estimulam uma imunidade predominantemente do tipo Th1 caracterizada pela produção de IFN-, IL-12, TNF- e óxido nítrico. A tuberculose, causada pelo patógeno intracelular Mycobacterium tuberculosis, é uma das doenças infecciosas mais importantes, sendo responsável por aproximadamente 2,9 milhões de óbitos e 8 milhões de novos casos por ano. Ainda são escassos os trabalhos envolvendo co-infecções, e devido às complexas relações existentes entre parasitos e entre eles e seu hospedeiro, faz-se necessário observações criteriosas. No presente trabalho avaliou-se o efeito modulatório que o Mycobacterium bovis virulento exerce sobre a resposta imune de camundongos co-infectados com S. venezuelensis. Os resultados demonstraram que o perfil de resposta imune durante a infecção por S. venezuelensis parece ser diretamente influenciado pela presença do M. bovis, uma vez que o perfil de resposta Th2, específico ao verme, esteve diminuído nos animais co-infectados. Tal diminuição pôde ser constatada pelo aumento do número de ovos e vermes nos animais co-infectados quando comparado com os animais infectados somente com S. venezuelensis; assim como a diminuição dos níveis de IgE específica à larva L3 do verme detectada em diferentes pontos da infecção; diminuição dos níveis de IL-10 produzida por células de baço estimuladas in vitro com antígeno da larva L3 do verme; diminuição dos níveis de IL-4, IL-5 e IL-13 no intestino; diminuição da expressão de CD80, CD86 e CD25 em células de baço e linfonodo e aumento da expressão de CD28 em células de linfonodos mesentéricos. Em conjunto, esses resultados sugerem que a infecção por M. bovis, e a conseqüente ativação do perfil de resposta imune do tipo Th1, foi capaz de modular o desenvolvimento do perfil de resposta imune do tipo Th2 contra S. venezuelensis nos animais co-infectados, deixando-os mais susceptíveis à infecção com S. venezuelensis. Esse trabalho é o primeiro a avaliar os mecanismos imunoregulatórios envolvidos na co-infecção S. venezuelensis versus M. bovis.
The intestinal parasites are a major medical-health problem, in view of the large number of people involved and the numerous organizational changes which may result in the host. Infections caused by Strongyloides venezuelensis have a local immune response in both lungs as in the intestine, predominantly from the Th2 type, characterized by the production of cytokines IL-4, IL-5, IL-13 and IL-10, resulting in eosinophilia, increased production of mucus, mastocytosis and high levels of IgE. In addition, infections caused by mycobacteria stimulate predominantly an Th1-type immune response characterized by the production of IFN-, IL-12, TNF- and nitric oxide. Tuberculosis, caused by intracellular pathogen Mycobacterium tuberculosis, is one of the most important infectious diseases, accounting for approximately 2.9 million deaths and 8 million new cases per year. Are still scarce papers involving co-infections, and because of the complex relationship between parasites and between them and their host, it is necessary criterious evaluations. This study evaluated the modulatory effect that the virulent Mycobacterium bovis has on the immune response of mice co-infected with S. venezuelensis. The results showed that the profile of immune response during infection with S. venezuelensis seems to be directly influenced by the presence of M. bovis, because the profile of Th2 response, specific to the worm, was reduced in co-infected animals. This decline could be observed by increasing the number of eggs and worms in animals co-infected when compared with animals infected only with S. venezuelensis, as well as decreased levels of IgE specific to the L3 larvae of the worm detected at different points of infection, decreased levels of IL-10 produced by spleen cells stimulated in vitro with L3 larvae antigen; decreased levels of IL-4, IL-5 and IL-13 in the intestine, reducing the expression of CD80, CD86 and CD25 cells in the spleen and lymph nodes and increased expression of CD28 cells in mesenteric lymph nodes. Together, these results suggest that infection with M. bovis, and the consequent activation of the profile of Th1-type immune response, was able to modulate the development of the profile of Th2 type of immune response against S. venezuelensis in co-infected animals, leaving them more susceptible to infection with S. venezuelensis. This work is the first to evaluate the mechanisms involved in imunoregulatory mechanisms involved in co-infection S. venezuelensis versus M. bovis.
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Tauber, James [Verfasser], Dirk [Gutachter] Hoffmeister, Erika [Gutachter] Kothe y Jonathan S. [Gutachter] Schilling. "Regulation of basidiomycete small molecules during co-culturing / James Patrick Tauber ; Gutachter: Dirk Hoffmeister, Erika Kothe, Jonathan S. Schilling". Jena : Friedrich-Schiller-Universität Jena, 2019. http://d-nb.info/1177386569/34.
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Lau, Jascha Alexander [Verfasser]. "Vibrational Energy Transfer Between CO Molecules on a NaCl(100) Surface Studied by Infrared Fluorescence Spectroscopy / Jascha Alexander Lau". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1232492876/34.
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Repeke, Carlos Eduardo Palanch. "Cinética de expressão de moléculas co-estimulatórias de osteoclastos no desenvolvimento da doença periodontal experimental e sua modulação por citocinas". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/25/25149/tde-08012013-164313/.
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O processo de diferenciação e ativação de osteoclastos, essencial para a manutenção da homeostasia do tecido ósseo e também envolvido na patogênese de diversas patologias caracterizadas pela atividade osteolítica, depende de um sistema central de controle que envolve a ligação das moléculas RANK/RANKL. Além do sistema RANK/RANKL, moléculas co-estimulatórias de osteoclastos, tais como os complexos DAP-12, TREM-2 e SIRP1, e FcR, OSCAR e PIR-A, também apresentam um papel importante na geração e ativação de osteoclastos. Entretanto, a possível contribuição de tais moléculas para a progressão da doença periodontal (DP) permanece desconhecida, assim como o possível impacto de citocinas na modulação de sua expressão no microambiente periodontal. Nosso objetivo foi investigar, por RealTimePCR, o padrão de expressão de moléculas co-estimulatórias de osteoclastos (DAP-12, TREM-2 e SIRP1, e FcR, OSCAR e PIR-A) na periodontite crônica em humanos, além de avaliar a cinética de expressão destas moléculas e a sua modulação por citocinas (TNF-, IFN-, IL-17 e IL-10) ao longo do curso da DP em camundongos em camundongos C57Bl/6 wild-type (WT) e geneticamente modificados (TNFp55KO, IFNKO, IL17KO, IL10KO. Nossos resultados demonstram que nas lesões periodontais crônicas a expressão de todas as moléculas co-estimulatórias de osteoclastos apresentaram-se significativamente aumentadas quando comparadas às amostras controle. Com relação à periodontite experimental, verificamos que todas as moléculas co-estimulatórias alvo apresentavam aumento em sua expressão após a indução de doença quando comparado aos controles. Nos camundongos para TNFp55KO, IFNKO e IL17KO, observamos uma redução na severidade da DP (reabsorção óssea e quantidade de células inflamatórias) e na expressão de moléculas co-estimulatórias, ao contrário do observado nos camundongos IL10KO. Entretanto, ao normalizarmos os níveis de expressão das moléculas co-estimulatórias de osteoclastos pelo número de células inflamatórias, verificamos que TNF- e IL-17 se mostram associados a uma maior expressão de moléculas co-estimulatórias, enquanto IFN- e IL-10 parecem regular negativamente a expressão de tais moléculas. Em termos gerais, demonstramos que a expressão de moléculas co-estimulatórias de osteoclastos se mostra aumentada na DP humana e experimental, e que citocinas parecem modular sua expressão por mecanismos diretos e indiretos, tais como a migração de células inflamatórias para os sítios de doença periodontal.The osteoclast differentiation and activation are essential to bone tissue homeostasis and in the development of bone pathologies, which RANK/RANKL signaling molecules are the major osteoclastogenic factor. However, osteoclast co-stimulatory molecules, such as DAP-12, TREM-2, SIRP1, FcR, OSCAR and PIR-A, also present an important role in the osteoclastogenesis. However, the exact role and regulation of these molecules in human and mice periodontal diseases (PD) development have not completely known. Our aim was to investigate the pattern of osteoclast co-stimulatory expression (DAP-12, TREM-2, SIRP1, FcR, OSCAR and PIR-A) in human chronic periodontitis (CP), apart from analyze the kinetic of these molecules and their regulation by cytokines (TNF-, IFN-, IL-17 and IL-10) in the development of experimental periodontal disease in mice C57Bl/6 and knockout. Our results demonstrated that all osteoclast co-stimulatory molecules presented highly expressed in CP patients when compared with control. Similar results are presented about experimental PD, where all co-stimulatory molecules was presented highly expressed in infected mice when compared with control mice. We observed in TNFp55KO, IFNKO and IL17KO mice a decrease in PD scores and co-stimulatory molecules expression, the opposite of IL10KO mice. However, when we standardized the co-stimulatory molecules levels by the number of inflammatory cells, we found that TNF- and IL-17 are associated with increased expression of co-stimulatory molecules, while IFN- and IL-10 appear to negatively regulate the expression of such molecules. In conclusion, we demonstrated that osteoclast co-stimulatory molecules shown increased in human and experimental PD, and cytokines appear to modulate their expression by direct and indirect mechanisms, such as inflammatory cells migration to the PD infected tissue.
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Ali, Radiya Gulnaz. "Co-operation between E-cadherin, phosphatidylinositol-3-kinase, Rac and the WASP family protein, WAVE2, is necessary for productive cadherin-dependent contact formation /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18991.pdf.
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Nagel, Christoph [Verfasser], Ulrich [Gutachter] Schatzschneider y Todd [Gutachter] Marder. "Novel manganese- and molybdenum-based photoactivatable CO-releasing molecules: synthesis and biological activity / Christoph Nagel. Gutachter: Ulrich Schatzschneider ; Todd Marder". Würzburg : Universität Würzburg, 2015. http://d-nb.info/1111509123/34.
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Tshivhidzo, Tsumbedzo Tertius. "AtNOGC1 protein bioelectrode for the determination of stress signalling molecules - Nitric Oxide (NO), Carbon Monoxide (CO) and Calcium ion (Ca2+)". University of the Western Cape, 2018. http://hdl.handle.net/11394/6332.
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Magister Scientiae - MSc (Biotechnology)It has been estimated that the world population will reach about 10 billion by the year 2050 and in order to accommodate the increased demand of food, the world agricultural production needs to rise by 70 % in the year 2030. However, the realisation of the goal in food production is hindered by limited arable land caused by urbanisation, salinisation, desertification and environmental degradation. Furthermore, abiotic and biotic stresses affect plant growth and development, which lead to major crop losses. The long term goal of this study is to improve food security by producing genetically engineered agricultural crops that will be tolerant to diverse stresses. This research aims at developing stress tolerant crops through the determination of important signalling molecules and second messengers, such as nitric oxide (NO), carbon monoxide (CO) and calcium ion (Ca2+), which can bind to plant proteins such as AtNOGC1 in order to induce stress tolerance in plants.
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Storz, Dennis [Verfasser] y Benito A. [Akademischer Betreuer] Yard. "Enzyme-triggered CO-releasing molecules (ET-CORMs): towards tissue-specific delivery of carbon monoxide / Dennis Storz ; Betreuer: Benito A. Yard". Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1211258890/34.
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Barnes, Peter J., Audra K. Hernandez, Stefan N. O’Dougherty, III William J. Schap y Erik Muller. "THE GALACTIC CENSUS OF HIGH- AND MEDIUM-MASS PROTOSTARS. III. 12 CO MAPS AND PHYSICAL PROPERTIES OF DENSE CLUMP ENVELOPES AND THEIR EMBEDDING GMCs". IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622167.
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We report the second complete molecular line data release from the Census of High-and Medium-mass Protostars (CHaMP), a large-scale, unbiased, uniform mapping survey at sub-parsec resolution, of millimeter-wave line emission from 303 massive, dense molecular clumps in the Milky Way. This release is for all (CO)-C-12 J = 1 -> 0 emission associated with the dense gas, the first from Phase II of the survey, which includes (CO)-C-12, (CO)-C-13, and (CO)-O-18. The observed clump emission traced by both (CO)-C-12 and HCO+ (from Phase I) shows very similar morphology, indicating that, for dense molecular clouds and complexes of all sizes, parsec-scale clumps contain. similar to 75% of the mass, while only 25% of the mass lies in extended (>10 pc) or "low density" components in these same areas. The mass fraction of all gas above a density of 10(9) m(-3) is xi(9) greater than or similar to 50%. This suggests that parsec-scale clumps may be the basic building blocks of the molecular interstellar medium, rather than the standard GMC concept. Using (CO)-C-12 emission, we derive physical properties of these clumps in their entirety, and compare them to properties from HCO+, tracing their denser interiors. We compare the standard X-factor converting I (CO)-C-12 to N-H2 with alternative conversions, and show that only the latter give whole-clump properties that are physically consistent with those of their interiors. We infer that the clump population is systematically closer to virial equilibrium than when considering only their interiors, with perhaps half being long-lived (10s of Myr), pressure-confined entities that only terminally engage in vigorous massive star formation, supporting other evidence along these lines that was previously published.
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French, Anne Thérèse. "The co-regulation of the mucus associated molecules intelectin, resistin like molecule beta and beta galactoside alpha 2-3 sialyltransferase in a T helper cell type 2 response". Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/28071.
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The mucus associated molecules intelectin (ITLN), resistin like molecule beta (RELMβ) and beta galactoside alpha 2-3 sialyltransferase (SIAT4C) are upregulated in nematode infections known to induce a typical T helper cell type 2 (Th2) response in mice. It was hypothesised that these three mucus-associated molecules were co-regulated by Th2 cytokines and that their upregulation was part of a typical anti-parasite response in other species. Sheep were chosen as a model because of the economic importance of both respiratory and gastrointestinal tract parasitic infections. Culture of a human colonic carcinoma cell line with either interleukin 4 (IL-4) or IL-13 confirmed the upregulation of ITLN and RELMβ in a Th2 environment however failed to show co-regulation with SIAT4C. Of the Th1 or Th2 cytokines examined only IFNγ had a significant effect on expression of SIAT4C transcript. ITLN transcript and protein was demonstrated in sheep tissue and furthermore three different ITLNs (sITLN1, sITLN2, sITLN3) which had a differential tissue distribution were cloned and sequenced. SIAT4C was widely expressed in sheep tissues and the full sequence was deduced. There was no evidence of expression of RELMβ sITLN transcripts were upregulated in response to IL-4 in an ex-vivo sheep tracheal explant culture model whilst sheep (s) SIAT4C was significantly downregulated in the same model. In a sheep model of infection with the abomasal nematode, Teladorsagia circumcincta, known to induce a Th2 biased response, sITLN transcripts and protein and sSIAT4C transcript were upregulated in response to a challenge infection. sITLN1 and sITLN2 were shown to upregulate at an earlier time point post challenge in previously infected (immune) compared to naïve yearling sheep and lambs and significant upregulation of sSIAT4C transcript was seen in challenged previously infected but not challenged naïve sheep and lambs. sITLNs and sSIAT4C may have an important role in the mucosal immune response to parasitic infections in sheep.
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Mitsuru, Hirano. "Elucidation of subcellular regulation of voltage-dependent calcium channel functions via β subunit interacting molecules". Kyoto University, 2017. http://hdl.handle.net/2433/226787.
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