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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Novel phosphorus containing poly(arylene ethers) as flame retardant additives and as reactant in organic synthesis

Satpathi, Hirak 08 June 2015 (has links)
Due to their outstanding properties, poly(arylene ethers) are useful as toughness modifiers in epoxy resins (EP). Furthermore, these polymers show rather low intrinsic fire risks. According to recent research it has been incorporated that poly(arylene ether phosphine oxides) [PAEPO’s] can further improve the fire behavior. Increasing phosphorous content of the PAEPO can influence the fire behavior too. Fire retardants containing phosphorus – regardless of whether an additive or reactive approach is used – show different mechanisms in the condensed and gas phase. In the present study PSU Control (BPA based polysulfone) with four different PAEPO’s and their corresponding blends with an EP were investigated. All poly(arylene ether phosphine oxides) were synthesized by nucleophilic aromatic polycondensation. The polymers obtained covered a wide range of weight average molar masses (6,000 – 150,000 g/mol) as determined by size exclusion chromatography with multi-angle light scattering detection (MALLS). FTIR, NMR spectroscopy and MALDI-TOF revealed formation of the desired polymer structure of the linear poly(arylene ethers). All polymers were easily soluble in common organic solvents, thus enabling processing from solution.The pyrolysis and the fire retardancy mechanisms of the polymers and blends with epoxy resin (EP) were tackled by means of a comprehensive thermal analysis (thermogravimetry (TG), TG-evolved gas analysis) and fire tests [PCFC, limiting oxygen index (LOI), UL-94, cone calorimeter]. The Mitsunobu reaction of Dimethyl-5-hydroxyisophthalate and a long chain semifluorinated alcohol requires triphenyl phosphine as a reactant. Identical, in some case higher yield was obtained in the usual conditions, with triphenyl phosphine and with trivalent phosphorus containing polymers, which was prepared in solvent free bulk (melt) polymerization technique from trivalent phosphorus monomer and a silylated diphenol in presence of CsF. Purification and the recovery of the final product which is always a big challenge in case of Mitsunobu reaction, was far more easier using polymer compared to triphenyl phosphine. During polymerization there was a possibility to have polymer having repeating unit containing both trivalent phosphorus and phosphine oxide. The trivalent phosphorus content of the polymer can be varied using different molar concentration of CsF.
262

From molecular germanates to microporous Ge@C via twin polymerization

Kitschke, Philipp, Walter, Marc, Rüffer, Tobias, Lang, Heinrich, Kovalenko, Maksym V., Mehring, Michael 31 March 2016 (has links)
Four molecular germanates based on salicyl alcoholates, bis(dimethylammonium) tris[2-(oxidomethyl)phenolate(2-)]germanate (1), bis(dimethylammonium) tris[4-methyl-2-(oxidomethyl)phenolate(2-)]germanate (2), bis(dimethylammonium) tris[4-bromo-2-(oxidomethyl)phenolate(2-)]germanate (3) and dimethylammonium bis[2-tert-butyl-4-methyl-6-(oxidomethyl)phenolate(2-)][2-tert-butyl-4-methyl-6-(hydroxymethyl)phenolate(1-)]germanate (4), were synthesized and characterized including single crystal X-ray diffraction analysis. In the solid state, compounds 1 and 2 exhibit one-dimensional hydrogen bonded networks, whereas compound 4 forms separate ion pairs, which are connected by hydrogen bonds between the dimethylammonium and the germanate moieties. The potential of these compounds for thermally induced twin polymerization (TP) was studied. Germanate 1 was converted by TP to give a hybrid material (HM-1) composed of phenolic resin and germanium dioxide. Subsequent reduction with hydrogen provided a microporous composite containing crystalline germanium and carbon (Ge@C – C-1, germanium content ∼20%). Studies on C-1 as an anode material for Li-ion batteries revealed reversible capacities of ∼370 mA h gGe@C−1 at a current density up to 1384 mA g−1 without apparent fading for 500 cycles. / Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
263

Количественное определение натриевой соли 2-этилтио-6-нитро-1,2,4-триазоло-[5,1-c]-1,2,4-триазин-7-она дигидрата методом вольтамперометрии : магистерская диссертация / Quantification of 2-ethylthio-6-nitro-1,2,4-triazolo-[5,1-c]-1,2,4-triazin-7-one sodium salt dihydrate by the method of voltammetry

Селянина, Т. В., Selyanina, T. V. January 2020 (has links)
Объектом исследования являлось вещество натриевая соль 2-этилтио-6-нитро-1,2,4-триазоло-[5,1-c]-1,2,4-триазин-7-она, дигидрат (УПИ-802). Цель работы: количественное определение лекарственного вещества натриевой соли 2-этилтио-6-нитро-1,2,4-триазоло-[5,1-c]-1,2,4-триазин-7-она дигидрата методом вольтамперометрии. В случае УПИ-802 наиболее полезным для количественного определения является сигнал электровосстановления нитрогруппы. Исследованы процессы восстановления нитрогруппы исследуемого вещества в водных и апротонных растворах с применением вольтамперометрии в условиях физического удаления растворенного кислорода и без удаления кислорода. Установлено, что скорость восстановления УПИ-802 контролируется диффузией, процесс восстановления нитрогруппы является необратимым и проходит в две стадии в буферном растворе Бриттона-Робинсона. Первая волна восстановления, которая лежит в области потенциалов -0,31 – (-0,8) В, соответствует присоединению 4 электронов. Обнаружено, что электровосстановление нитрогруппы протекает с предшествующим протонированием. Выбран оптимальный режим регистрации аналитического сигнала исследуемого вещества УПИ-802 на стеклоуглеродном электроде в условиях химического способа удаления растворенного кислорода – квадратно-волновой с амплитудой импульса 0,05 В, частотой импульса 35 Гц. Показана возможность применения толстопленочных углеродсодержащих электродов для определения исследуемого вещества методом квадратно-волновой вольтамперометрии. Выполнена оценка показателей качества методики анализа, таких как линейность, повторяемость (сходимость) и внутрилабораторная прецизионность. / The object of the study was the substance 2-ethylthio-6-nitro-1,2,4-triazolo-[5,1-c]-1,2,4-triazin-7-one sodium salt dihydrate (UPI-802). Objective: quantification of 2-ethylthio-6-nitro-1,2,4-triazolo-[5,1-c]-1,2,4-triazin-7-one sodium salt dihydrate by the method of voltammetry. For UPI-802, the signal of electroreduction of a nitro group is the most useful for quantitative determination. The processes of the nitro group reduction of the test substance in aqueous and aprotic solutions was studied using voltammetry in conditions of physical removal of dissolved oxygen and without oxygen removal. It was established that the rate of reduction of UPI-802 is controlled by diffusion, the processes of reduction of the nitro group is irreversible and proceeds in two stages in a Britton-Robinson buffer solution. The first recovery wave, lying in the potential region of -0,31 - (-0,8) V, corresponds to the addition of 4 electrons. It was found that the electroreduction of the nitro group proceeds with previous protonation. The optimal mode for recording the analytical signal of the UPI-802 on the glassy carbon electrode was selected in conditions of chemical method for removing dissolved oxygen – square-wave with a pulse amplitude of 0,05 V and a pulse frequency of 35 Hz. The possibility of using thick-film carbon-containing electrodes to determine the test substance by the method of square-wave voltammetry was shown. The quality indicators of the analysis technique, such as linearity, repeatability (convergence) and intralaboratory precision, were evaluated.
264

Rôles de DICAM et ALCAM dans la migration des lymphocytes vers le système nerveux central

Grasmuck, Camille 04 1900 (has links)
La perturbation de la barrière hémo-encéphalique et la migration des lymphocytes de la périphérie vers le système nerveux central (SNC) sont des événements précoces dans la formation des lésions cérébrales de sclérose en plaques (SEP). Dans ce contexte, les lymphocytes passent au travers des barrières hémo-encéphalique ou hémo-méningée pour atteindre le SNC et sont des contributeurs importants dans l’inflammation et les dommages tissulaires. Pour migrer à travers les barrières du SNC, les lymphocytes pathogéniques expriment des molécules d’adhérence. Identifier les acteurs clés à la migration des lymphocytes pathogéniques en estimant la contribution des molécules d’adhérence dans ce processus est la prochaine étape pour le développement de thérapies pour traiter la SEP. L’objectif de ce projet est d’explorer le rôle de deux molécules d’adhérence que sont ALCAM (de l’anglais : activated leukocytes cell adhesion molecule) et DICAM (de l’anglais : dual immunoglobulin domain containing cell adhesion molecule) dans la migration des lymphocytes pathogéniques vers le SNC pendant la SEP. Notre objectif principal se subdivise en deux sous-objectifs. En premier, notre but est de caractériser le rôle d’ALCAM dans le passage des lymphocytes B à travers les barrières du SNC dans un contexte neuroinflammatoire. En second, nous explorons le rôle de DICAM dans la migration des lymphocytes T auxiliaires 17 (TH17) vers le SNC en neuroinflammation. Nous faisons l’hypothèse qu’ALCAM contribue à la migration des lymphocytes B vers le SNC et que DICAM est impliqué dans la migration des lymphocytes TH17 à travers la barrière hémo-encéphalique pendant la SEP. Ces molécules d’adhérence seraient alors impliquées dans la pathogenèse de la SEP et seraient de potentielles cibles thérapeutiques pour traiter cette maladie. Nous avons d’abord utilisé une combinaison de spectrométrie de masse, PCR quantitative, cytométrie de flux et microscopie afin d’explorer l’expression de chacune de ses deux molécules d’adhérence sur les lymphocytes d’intérêt périphériques ex vivo ou différenciés in vitro. Des analyses en cytométrie en flux et microscopie nous ont permis de caractériser leur expression dans le sang périphérique et dans les lésions cérébrales de personnes atteintes de SEP. Ensuite, les expériences d’adhérence en flux et de migration in vitro effectuées en déplétant la molécule d’adhérence d’intérêt ont permis de mettre en évidence leur rôle dans différentes étapes de la migration des lymphocytes à travers les cellules endothéliales des barrières du SNC. Pour finir, le traitement de plusieurs modèles murins de SEP, appelés EAE (de l’anglais : experimental autoimmune encephalomyelitis), avec des anticorps bloquant anti-ALCAM ou anti-DICAM ont permis d’explorer le potentiel effet de tels traitements sur la sévérité de la maladie. Dans la première étude, nos résultats montrent qu’ALCAM est préférentiellement exprimée par les lymphocytes B pro-inflammatoires, mémoires et effecteurs au potentiel pathogénique. En tant que molécule d’adhérence, ALCAM contribue à leur migration à travers les cellules endothéliales des barrières hémo-encéphalique et hémo-méningée chez la souris et l’humain. De plus, nos expériences ont permis de montrer que la fréquence de lymphocytes B ALCAM+ est augmentée dans le sang périphérique des personnes atteintes de SEP et ces cellules sont aussi présentes dans les lésions et les infiltrats méningées en SEP. Finalement, bloquer ALCAM in vivo réduit la sévérité de la maladie EAE en diminuant l’infiltration des lymphocytes B au SNC. Dans la seconde étude, nous avons montré que parmi les sous-types de lymphocytes TH, DICAM est préférentiellement exprimée par les lymphocytes TH17. Dans les lésions de SEP, DICAM et son ligand αVβ3 co-localisent avec des marqueurs de cellules endothéliales suggérant que ces deux molécules pourraient être présentées à la lumière des vaisseaux aux lymphocytes TH17 circulants. Dans le sang périphérique, la fréquence de lymphocytes T CD4+ exprimant DICAM est augmentée chez les personnes atteintes de SEP et cette augmentation corrèle avec l’activité de la maladie. Nos expériences ont montré que DICAM est impliquée dans l’adhérence, l’arrêt et la diapédèse des lymphocytes TH17 à travers les cellules endothéliales de la barrière hémo-encéphalique in vitro et in vivo. Finalement, le traitement de souris EAE avec un anticorps bloquant DICAM permet de réduire la sévérité de la maladie et diminue la migration des lymphocytes TH17 vers le SNC. Nos résultats indiquent un rôle d’ALCAM dans la migration des lymphocytes B et que DICAM, préférentiellement exprimé par les TH17, médie leur migration vers le SNC. Bloquer ALCAM ou DICAM sont deux stratégies permettant de réduire l’accès au SNC de différents sous-types de cellules pathogéniques pendant la neuroinflammation. Ainsi, elles sont toutes deux de potentielles cibles thérapeutiques pour réduire la sévérité et la progression de la SEP. / Disruption of the blood-brain barrier and migration of lymphocytes from the periphery to the central nervous system (CNS) are early events in lesion formation during multiple sclerosis (MS). Lymphocytes readily cross the blood-brain barrier (BBB) and the blood-meningeal barrier (BMB) to infiltrate the CNS and are important contributors to inflammation and tissue damage. To migrate through the brain barriers, pathogenic lymphocytes express adhesion molecules. Identifying key players in lymphocyte migration by understanding the role of adhesion molecules is the next step to develop novel therapies to treat MS. The objective of this project is to explore the role of two distinct adhesion molecules ALCAM (activated leukocytes cell adhesion molecule) and DICAM (dual immunoglobulin domain containing cell adhesion molecule) in pathogenic lymphocytes migration to the CNS during MS. This thesis subdivides in two main objectives. First, we aim to characterize ALCAM role in B lymphocyte migration to the CNS during neuroinflammation. Second, we aim to explore DICAM role in T helper 17 (TH17) lymphocytes migration to the CNS in neuroinflammation. We hypothesized that ALCAM plays a role in B lymphocytes migration to the CNS during MS and that DICAM is involved in TH17 lymphocytes migration through the blood-brain barrier during MS. Those adhesion molecules might be involved in MS pathogenesis and therefore could become new therapeutic targets to treat MS. We first used mass spectrometry, quantitative PCR, flow cytometry and confocal microscopy to explore expression profiles of ALCAM and DICAM by peripheral lymphocytes subpopulations ex vivo and differentiated in vitro. Flow cytometry and confocal microscopy analysis also revealed how those adhesion molecules are expressed by lymphocytes in peripheral blood and brain lesions of people living with MS. Then, we performed flow adhesion and migration assay of lymphocytes depleted for the adhesion molecule of interest allowing us to address their role in multitstep migration process through brain barriers endothelial cells. Finally, using five distinct murine experimental autoimmune encephalomyelitis models (EAE), we explored how blocking ALCAM or DICAM in vivo could affect lymphocytes migration to the SNC and disease severity. In the first manuscript, we described that ALCAM is preferentially expressed by B lymphocytes with memory, pro-inflammatory and effector phenotypes. Functionally, ALCAM is involved in B lymphocyte migration through both the BBB and the BMB in mouse and human. Interestingly, we showed that ALCAM expressing B lymphocytes are increased in peripheral blood of people living with MS and they are recovered in meningeal and parenchymal MS lesions. Last, blocking ALCAM in vivo alleviates EAE severity by reducing B lymphocyte infiltration to the CNS. In the second manuscript, we showed that TH17 lymphocytes preferentially express DICAM and can adhere both to DICAM and its ligand αVβ3. Moreover, DICAM and αVβ3 are both overexpressed by inflamed brain endothelial cells. In MS lesions, we described that both molecules colocalize with endothelial cell markers suggesting that it could be presented to the vessel lumen to the circulating TH17 lymphocytes. In peripheral blood, we showed that DICAM+ memory CD4+ T lymphocytes frequency is increased in people living with MS and it correlates with active form of the disease. Then, we described DICAM as a player in TH17 lymphocyte adhesion, arrest and migration through BBB endothelial cells in vitro and in vivo. Last, we showed that treating mice with a neutralizing DICAM antibody in several distinct models of EAE, reduced disease severity and TH17 cell migration to the SNC. Our data provide evidence of the role of ALCAM in memory B lymphocyte migration and that DICAM is preferentially expressed by TH17 cells and mediate their migration to the CNS during neuroinflammation. Collectively, our findings indicate that blocking ALCAM or DICAM are two ways to restrict different pathogenic cells access to the CNS during neuroinflammation and thus potentially to reduce the severity and worsening of a disease like MS.
265

Etude ultra-sensible en phase de nano-structures par interferométrie optique à balayage en champ proche / A study on ultra-sensitive phase in nano-structures by near-field scanning optical interferometry

Mok, Jinmyoung 26 March 2015 (has links)
La construction d’un NSOM, dans ce manuscrit de thèse, est décrite en détail. Lacombinaison du système NSOM construit avec un interféromètre est proposée afin d’accéderà des mesures de phase, à la fois de ultra-haute sensibilité mais également de très granderésolution spatiale. Le nom de l’instrument développé est un interferomètre optique àbalayage en champ proche (NSOI, pour l’acronyme en anglais). Le principe est basé surl’utilisation d’un diapason accordable en cristal de quartz, sur lequel se trouve une pointe,afin de sonder le matériau étudié. La mesure de la force de cisaillement de la pointe sondeau voisinage de la surface permet d’assurer la régulation et la stabilité de la distance depositionnement de la pointe par rapport à la surface considérée. Le dispositif est construit encombinant différents éléments électroniques pilotés par un logiciel développé en langageLab-VIEW. Le bruit de la mesure en NSOI est supprimé par un calcul simple basé sur lathéorie de l’optique ondulatoire et des interférences associées. Le système permet deréaliser des mesures optiques en champ proche ainsi que la détermination en hauterésolution de la phase du champ optique. L’échantillon SNG01 (l’un des réseaux utilisés pourcaractériser notre microscope à balayage en champ proche), ainsi que des disques optiques(CD, DVD and disques blu-ray) ont été utilisés pour tester la faisabilité et les performancesde notre système.Dans ce manuscrit de thèse, le graphène et les monocouches de MoS2 sont étudiés. Nous montrons qu’une épaisseur à l’échelle atomique peut être résolue par notresystème NSOI, avec l’utilisation de l’algorithme de suppression du bruit de mesure. Lesjoints de grain du graphène sont observés à grande échelle, via la technique d’imagerie parcollection en champ proche et par la réalisation de cartographies de phase. En particulier,les tensions internes à une couche de graphène sont observées, uniquement dans le casd’une imagerie de phase. / In this thesis, near-field scanning optical interferometry (NSOI), which combinesNSOM with interferometer, is proposed for the phase measurement. The shear-forcedetection scheme is applied for distance regulation. The hardware of the systemis constructed by combining various electronic devices, and the operating softwareis coded by LabVIEW. Unwanted background signal is removed by simple calculationbased on interference theory. By using this, the near-field optical measurementand the ultra-sensitive phase investigation of nano-materials are performed. 2D materialssuch as graphene and monolayer MoS2 are investigated. It is shown thatatomic-scale thickness can be resolved by the NSOI. Especially, the grain boundariesof graphene and the seed of MoS2 can be found by phase detection. In addition,direct laser writing (DLW) on silver-containing glass is observed by using NSOM,and NSOI. For the first time, the writing threshold is correlatively observed in thefluorescence imaging and the near-field phase image.
266

Experimental and theoretical studies on germanium-containing precursors for twin polymerization

Kitschke, Philipp 10 June 2016 (has links)
Im Fokus dieser Arbeit standen zwei Ziele. Zum einem war es Forschungsgegenstand, dass Konzept der Zwillingspolymerisation auf germaniumhaltige, molekulare Vorstufen wie zum Beispiel Germylene, spirozyklische Germaniumverbindungen und molekulare Germanate zu erweitern und somit organisch-anorganische Komposite beziehungsweise Hybridmaterialien darzustellen. Dazu wurden neuartige Germaniumalkoxide auf der Basis von Benzylalkoholaten, Salicylalkoholaten sowie Benzylthiolaten synthetisiert, charakterisiert und auf ihre Fähigkeit Komposite beziehungsweise Hybridmaterialien über den Prozess der Zwillingspolymerisation zu erhalten studiert. Ein zweites Ziel dieser Arbeit war es, Beziehungen zwischen der Struktur und der Reaktivität dieser molekularen Vorstufen sowie deren Einfluss auf die Eigenschaften der erhaltenen Polymerisationsprodukte zu identifizieren und systematisch zu untersuchen. Hierfür wurden zum einen verschiedene Substituenten, welche unterschiedliche elektronische sowie sterische Eigenschaften aufweisen, an den aromatischen Einheiten der molekularen Vorstufen eingeführt. Die Effekte der Substituenten auf den Prozess der Zwillingspolymerisation und auf die Eigenschaften der Komposite beziehungsweise Hybridmaterialien wurden für die Verbindungsklasse der Germanium(II)salicylalkoholate, der molekularen Germanate sowie der spiro-zyklischen Siliziumsalicylalkoholate untersucht. Spirozyklische Siliziumsalicylalkoholate, wie zum Beispiel 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin], wurden im Rahmen dieser Arbeit mit einbezogen, da sie aufgrund ihres nahezu idealen Zwillingspolymerisationsprozesses geeignete Modelverbindungen für Reaktivitätsstudien darstellen. Zudem wurde der Einfluss der Substituenten auf die Charakteristika der aus den Kompositen beziehungsweise Hybridmaterialien erhaltenen Folgeprodukte (poröse Kohlenstoffmaterialien und oxydische Materialien) studiert. Des Weiteren wurde eine Serie von spirozyklischen Germaniumthiolaten, welche isostrukturell zu 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin] sind, synthetisiert, um systematisch den Einfluss der Chalkogenide, Sauerstoff und Schwefel, in benzylständiger sowie phenylständiger Position auf deren Reaktionsvermögen im Polymerisationsprozess zu untersuchen. Die experimentellen Ergebnisse zu den Struktur-Reaktivitätsbeziehungsstudien wurden, soweit es jeweils durchführbar war, mittels quantenchemische Rechnungen validiert und die daraus gezogenen Schlüsse in die Diskussion zur Interpretation der experimentellen Ergebnisse mit einbezogen.:Contents List of Abbreviations S. 11 1 Introduction S.14 2 Germanium alkoxides and germanium thiolates S. 18 2.1 Preamble S. 18 2.2 Germanium alkoxides S. 18 2.2.1 Germanium(II) alkoxides S. 20 2.2.2 Germanium(IV) alkoxides S. 23 2.2.3 Alkoxidogermanates S. 29 2.3 Germanium thiolates S. 31 2.3.1 Germanium(II) thiolates S. 33 2.3.2 Germanium(IV) thiolates S. 34 2.3.3 Thiolatogermanates and cationic germanium thiolato transition metal complexes S. 36 2.4 Germanium alkoxido thiolates S. 38 2.5 Concluding remarks S. 40 3 Individual Contributions S. 43 4 Microporous Carbon and Mesoporous Silica by Use of Twin Polymerization: An integrated Experimental and Theoretical Approach on Precursor Reactivity S. 46 4.1 Abstract S. 46 4.2 Introduction S.46 4.3 Results and Discussion S. 48 4.3.1 Synthesis and Characterization S. 48 4.3.2 Thermally induced twin polymerization of monosubstituted Precursors (para position) S.49 4.3.2.1 Studies on reactivity according to thermally induced twin polymerization S. 50 4.3.2.2 Characterization of the hybrid materials as obtained by thermally induced twin polymerization S. 51 4.3.2.3 Thermally induced twin polymerization of di-substituted precursors (ortho and para position) S. 52 4.3.2.4 Conclusions drawn for the thermally induced twin polymerization S. 54 4.3.3 Proton-assisted twin polymerization S. 54 4.3.3.1 Studies on the reactivity according to proton-assisted twin polymerization S.55 4.3.3.2 Characterization of the hybrid materials as obtained by proton-assisted twin polymerization S.56 4.3.3.3 Computational studies on proton-assisted twin polymerization S. 58 4.3.3.4 Conclusions drawn for the process of proton-assisted twin polymerization S. 60 4.3.4 Characterization of the porous materials S.61 4.4 Conclusions S.64 4.5 Experimental Section S. 65 4.5.1 General S.65 4.5.2 General procedure for the synthesis of phenolic resin-silica hybrid materials by thermally induced twin polymerization in melt - exemplified for compound 1 S. 66 4.5.3 General procedure for the synthesis of phenolic resin-silica hybrid materials by proton-assisted twin polymerization in solution - exemplified for compound 1 S. 66 4.5.4 General procedure for the synthesis of microporous carbon - exemplified for hybrid material HM-1T S. 66 4.5.5 General procedure for the synthesis of mesoporous silica - exemplified for hybrid material HM-1T S. 67 4.5.6 Single-Crystal X-ray Diffraction Analyses S. 67 4.5.7 Computational Details S. 67 4.6 Acknowledgments S. 68 4.7 Keywords S.68 4.8 Supporting Information Chapter 4 S. 69 5 Synthesis of germanium dioxide nanoparticles in benzyl alcohols – a comparison S. 82 5.1 Abstract S. 82 5.2 Introduction S. 82 5.3 Results and Discussion S.83 5.4 Conclusions S. 87 5.5 Experimental Section S. 87 5.5.1 General S. 87 5.5.2 Syntheses S. 88 5.5.3 Synthesis of GeO2 in ortho-methoxy benzyl alcohol – sample A S. 88 5.5.4 Synthesis of GeO2 in benzyl alcohol under inert conditions – sample B S. 89 5.5.5 Synthesis of GeO2 in benzyl alcohol under ambient conditions – sample C S. 89 5.6 Acknowledgments S. 89 5.7 Keywords S.89 5.8 Supporting Information Chapter 5 S. 90 6 From a Germylene to an “Inorganic Adamantane”: [{Ge₄(μ-O)₂(μ-OH)₄}{W(CO)₅}₄]∙4THF S. 93 6.1 Abstract S.93 6.2 Introduction S. 93 6.3 Results and Discussion S. 94 6.4 Conclusions S. 98 6.5 Experimental Section S. 99 6.5.1 General S.99 6.5.2 Synthesis of germanium(II) (2-methoxyphenyl)methoxide (9) S. 99 6.5.3 Synthesis of [{Ge4(μ-O)2(μ-OH)4}{W(CO)5}4]·4THF (10·4THF) S. 100 6.5.4 Single-Crystal X-ray Diffraction Analyses S. 100 6.5.4.1 Crystal Data for (9)2 S. 101 6.5.4.2 Crystal Data for 10·4THF S. 101 6.5.5 Computational Details S. 101 6.6 Acknowledgments S. 101 6.7 Keywords S.101 6.8 Supporting Information Chapter 6 S. 102 7 Synthesis, characterization and Twin Polymerization of a novel dioxagermine S. 110 7.1 Abstract S. 110 7.2 Introduction S.110 7.3 Results and Discussion S. 111 7.3.1 Single-crystal X-ray diffraction analysis S. 111 7.3.2 IR spectroscopy S. 112 7.3.3 Mass spectrum S. 114 7.3.4 DSC/TGA analysis S. 116 7.3.5 Polymerization S. 117 7.4 Conclusions S. 118 7.5 Materials and Methods S.118 7.5.1 General S. 118 7.5.2 Synthesis of 5-bromo-2-hydroxybenzyl alcohol S. 119 7.5.3 Synthesis of di-tert-butyl-di-ethoxy germane S.119 7.5.4 Synthesis of 6-bromo-2,2-di-tert-butyl-4H-1,3,2-benzo[d]dioxagermine (11) S. 120 7.5.5 Polymerization of compound 11 S. 120 7.5.6 X-ray diffraction analysis of compound 11 S.120 7.5.6.1 Crystal data for compound 11 S.120 7.5.7 Computational Details S.121 7.6 Acknowledgments S.121 7.7 Keywords S. 121 7.8 Supporting Information Chapter 7 S. 122 8 Intramolecular C-O Insertion of a Germanium(II) Salicyl Alcoholate: A Combined Experimental and Theoretical Study S. 125 8.1 Abstract S.125 8.2 Introduction S. 125 8.3 Results and Discussion S.126 8.3.1 Syntheses and Characterization S. 126 8.3.2 1H NMR Spectroscopic Studies S.132 8.3.3 DFT-D Calculations S.134 8.4 Conclusions S. 137 8.5 Experimental Section S. 138 8.5.1 General S. 138 8.5.2 Synthesis of germanium(II) 2-tert-butyl-4-methyl-6-(oxidomethyl)phenolate (12) S. 139 8.5.3 Synthesis of 2,4,6,8-tetrakis(3-tert-butyl-5-methyl-2-oxidophenyl)methanide-1,3,5,7,2,4,6,8-tetraoxidogermocane (13) S. 139 8.5.3.1 Method a) S.139 8.5.3.2 Method b) S. 140 8.5.4 Synthesis of 7,8'-di-tert-butyl-5,6'-dimethyl-3H,4'H-spiro[benzo[d][1,2]oxager-mole-2,2'-benzo[d][1,3,2]dioxagermine] (14) S. 140 8.5.4.1 Method a) S. 140 8.5.4.2 Method b) S. 141 8.5.4.3 Method c) S. 141 8.5.5 Synthesis of the [4-(dimethylamino)pyridine][germanium(II)-2-tert-butyl-4-meth-yl-6-(oxidomethyl)phenolate] (15) S. 141 8.5.6 1H NMR spectroscopic study i) S. 142 8.5.7 1H NMR spectroscopic study ii) S. 142 8.5.7.1 Method a) S. 142 8.5.7.2 Method b) S. 142 8.5.8 1H NMR spectroscopic study iii) S. 142 8.5.8.1 Method a) S. 142 8.5.8.2 Method b) S. 142 8.5.9 1H NMR spectroscopic study iv) S. 143 8.5.10 1H NMR spectroscopic study of the mixture of complex 15 and 3-tert-butyl-2-hydroxy-5-methylbenzyl alcohol in CDCl3 S. 143 8.5.11 1H NMR spectroscopic study of complex 15 in CDCl3 at elevated temperature S. 143 8.5.12 Reaction of complex 15 at elevated temperature S. 143 8.5.13 Single-crystal X-ray diffraction analyses S. 143 8.5.14 Computational Details S.144 8.6 Acknowledgments S. 145 8.7 Keywords S.145 8.8 Supporting Information Chapter 8 S. 146 9 Porous Ge@C materials via twin polymerization of germanium(II) salicyl alcoholates for Li-ion batteries S. 159 9.1 Abstract S. 159 9.2 Introduction S. 159 9.3 Results and Discussion S. 160 9.3.1 Synthesis and Characterization of germylenes S. 160 9.3.2 Twin polymerization S. 164 9.3.2.1 Studies on the reactivity S. 164 9.3.2.2 Characterization of the hybrid materials obtained by thermally induced twin polymerization S. 166 9.3.3 Synthesis and characterization of porous materials S. 168 9.3.4 Electrochemical measurements S. 170 9.4 Conclusions S. 172 9.5 Experimental Section S.172 9.5.1 General S.172 9.5.2 Synthesis of germanium(II) 2-(oxidomethyl)phenolate (16) S. 174 9.5.3 Synthesis of germanium(II) 4-methyl-2-(oxidomethyl)phenolate (17) S. 174 9.5.4 Synthesis of germanium(II) 4-bromo-2-(oxidomethyl)phenolate (18) S. 175 9.5.5 General procedure for the synthesis of phenolic resin-germanium oxide hybrid materials by thermally induced twin polymerization in melt - exemplified for compound 16 S. 175 9.5.6 General procedure for the synthesis of porous Ge@C materials - exemplified for hybrid material HM-16 S.175 9.5.7 General procedure for the synthesis of germanium oxide - exemplified for hybrid material HM-16 S.176 9.5.8 Single-crystal X-ray diffraction analyses S. 176 9.5.9 Computational Details S. 177 9.5.10 Electrode fabrication, cell assembly and electrochemical measurements S. 178 9.6 Acknowledgments S.178 9.7 Keywords S. 178 9.8 Supporting Information Chapter 9 S.179 10 From molecular germanates to microporous Ge@C via twin polymerization S.199 10.1 Abstract S.199 10.2 Introduction 199 10.3 Results and Discussion S. 201 10.3.1 Syntheses and Characterization S. 201 10.3.2 Twin polymerization of germanate 19 S. 204 10.3.3 Synthesis and characterization of the porous materials S. 205 10.3.4 Electrochemical measurements S.206 10.4 Conclusions S. 207 10.5 Experimental Section S. 208 10.5.1 General S. 208 10.5.2 Synthesis of bis(dimethylammonium) tris[2-(oxidomethyl)phenolate(2-)]germa-nate (19) S. 209 10.5.3 Synthesis of bis(dimethylammonium) tris[4-methyl-2-(oxidomethyl)pheno-late(2-)]germanate (20) S. 210 10.5.4 Synthesis of bis(dimethylammonium) tris[4-bromo-2-(oxidomethyl)pheno-late(2-)]germanate (21) S.210 10.5.5 Synthesis of dimethylammonium bis[2-tert-butyl-4-methyl-6-(oxidomethyl)phe-nolate(2-)][2-tert-butyl-4-methyl-6-(hydroxymethyl)phenolate(1-)]germanate (22) S. 211 10.5.6 Synthesis of phenolic resin-germanium dioxide hybrid materials by thermally induced twin polymerization in melt - HM-19 S. 211 10.5.7 Synthesis of porous Ge@C material C-19 starting from HM-19 S. 212 10.5.8 Synthesis of germanium dioxide material Ox-19 - starting from HM-19 S.212 10.5.9 Single-crystal X-ray diffraction analyses S. 212 10.5.10 Electrode fabrication, cell assembly and electrochemical measurements S.213 10.6 Acknowledgments S. 214 10.7 Keywords S. 214 10.8 Supporting Information Chapter 10 S.215 11 Chiral Spirocyclic Germanium Thiolates – An Evaluation of Their Suitability for Twin Polymerization based on A Combined Experimental and Theoretical Study S.226 11.1 Abstract S.226 11.2 Introduction S. 226 11.3 Results and Discussion S.227 11.3.1 Syntheses and Characterization S. 227 11.3.2 Studies on twin polymerization S.229 11.3.3 Computational studies on proton-assisted twin polymerization S. 232 11.4 Conclusions S. 235 11.5 Acknowledgments S. 236 11.6 Keywords S.236 11.7 Supporting Information Chapter 11 S.237 12 Concluding remarks S. 257 12.1 Discussion S.257 12.1.1 Twin polymerization of germanium-containing precursors S. 257 12.1.2 Reactivity studies of precursors towards their twin polymerization S.260 12.2 Summary and Outlook S. 264 Selbständigkeitserklärung S.266 Curriculum Vitae S.267 Publications S. 268 List of Publications in Peer-Reviewed Journals S. 268 List of Conference Contributions S.269 Research proposals, additional conference and summer school participations S. 270 Acknowledgments S. 271 References S. 272
267

The ARMC5-Cullin3-RBX1 forms an RPB1-specific ubiquitin ligase essential for RNA polymerase II homeostasis

Lao, Linjiang 02 1900 (has links)
ARMC5 est une protéine qui contient sept motifs Armadillo répétitifs organisés en tandem et un domaine BTB. Nous avons observé que cette protéine était fortement exprimée dans les organes lymphoïdes, les glandes surrénales et le cerveau. Les souris avec une délétion d’Armc5 (souris KO) étaient de petite taille, et présentaient une diminution de la prolifération et la différenciation des lymphocytes T. L’absence d’ARMC5 entraînait une déficience de la réponse immunitaire médiée par les lymphocytes CD4+ et CD8+ dans les modèles expérimentaux d’encéphalomyélite auto-immune et d’infection au virus de la chorioméningite lymphocytaire, respectivement. Par la suite, plusieurs études ont révélé que la mutation ARMC5 était associée à l’hyperplasie macronodulaire bilatérale primitive des surrénales (HMBPS), qui représente une cause rare du syndrome de Cushing. Nous avons ensuite confirmé que l’hyperplasie des glandes surrénales s’était développée chez les souris KO âgées, et qu’elle s’accompagnait d’une légère augmentation des taux sériques de glucocorticoïdes. Comme ARMC5 ne présentait pas d’activité enzymatique, il était probable qu’elle faisait appel à d’autres protéines pour exercer sa fonction. Nous avons identifié plusieurs protéines qui se liaient à ARMC5, et plus particulièrement le complexe ARMC5/Cullin3 qui formait une ubiquitine ligase (E3) spécifique de la sous-unité RPB1 de l’ARN polymérase II. ARMC5 contrôlait le processus d’ubiquitination de RPB1 qui, par conséquent, s’accumulait dans plusieurs organes majeurs : les glandes surrénales, les ganglions lymphatiques, le cerveau, les poumons, le foie, etc. chez la souris KO. Ces résultats démontrent un rôle clé de l’ubiquitine ligase dans la dégradation de la protéine RPB1. Une accumulation similaire a également été observée dans les tissus hyperplasiques des surrénales provenant de patients atteints d’HMBPS et porteurs de la mutation ARMC5, ce qui souligne la pertinence clinique de nos résultats de recherche fondamentale dans les maladies humaines. Un défaut de dégradation de RPB1 augmentait le pool d’ARN polymérase II. Par ailleurs, nous avons identifié un groupe de gènes fortement surexprimés dans les glandes surrénales déficientes en ARMC5, parmi lesquels figurent les gènes effecteurs qui seraient impliqués dans l’hyperplasie des surrénales chez les souris KO et l’HMBPS chez les patients porteurs de la mutation ARMC5. Finalement, nous avons montré que la délétion ou la mutation d’Armc5 augmentait considérablement le risque des anomalies du tube neural chez les souris et les humains. Chez les patients souffrant de myéloméningocèle, nous avons constaté neuf différentes mutations faux-sens délétères, dont une diminuait l’interaction entre ARMC5 et RPB1. L’augmentation du pool d’ARN polymérase II dans les cellules précurseurs neurales (CPN), causée par la délétion ARMC5, influençait un groupe particulier de gènes, dont certains (p. ex. Folh1) seraient susceptibles de participer au développement du tube neural. En résumé, l’association ARMC5 et Cullin3 forme un complexe E3 qui cible RPB1 provoquant son ubiquitination et sa dégradation. En absence d’un tel mécanisme, on observe une perturbation de l’homéostasie de l’ARN polymérase II, qui mène à une diminution de la réponse immunitaire médiée par lymphocytes T, le développement d’HMBPS et un risque accru d’anomalies du tube neural. / ARMC5 protein contains seven tandem Armadillo repeats and one BTB domain. We observed that Armc5 was highly expressed in the lymphatic organs, adrenal glands, and brain. Armc5 knockout (KO) mice were small in size and exhibited compromised T cell proliferation and differentiation. The absence of ARMC5 resulted in an impairment of the CD4 + cell- and CD8 + cell-mediated immune response in the experimental autoimmune encephalomyelitis model and lymphocytic choriomeningitis virus infection model, respectively. Subsequently, several studies revealed that ARMC5 mutations were related to primary bilateral macronodular adrenal hyperplasia (PBMAH), which is a rare cause of Cushing’s syndrome. We then confirmed that adrenal gland hyperplasia was indeed developed in aged Armc5 KO mice with mildly increased serum glucocorticoid levels. Since ARMC5 did not exhibit enzymatic activity, its function likely depends on the interaction with other proteins. We identified several proteins that binds to ARMC5, most notably ARMC5 binding to Cullin3, forming a ubiquitin ligase (E3) specific for RNA polymerase II subunit I (RPB1). ARMC5 regulated the ubiquitination of RPB1, and its deletion resulted in RPB1 accumulation in major organs (e.g., adrenal glands, lymph nodes, brain, lung, and liver), indicating the critical role of this E3 in RPB1 degradation. A similar accumulation was also found in hyperplasia tissues from adrenal glands of PBMAH patients carrying ARMC5 mutations, underscoring the clinical relevance of our basic research findings in human disease. Defective degradation of RPB1 led to an enlarged RNA polymerase II (Pol II) pool. In addition, we have identified a group of genes strongly upregulated in KO adrenal glands, including the effector genes which would be involved in adrenal gland hyperplasia in Armc5 KO mice and PBMAH patients carrying ARMC5 mutation. Finally, we have shown that deleting or mutating Armc5 significantly augments the risk of neural tube defects in mice and humans. In patients with myelomeningocele, we found nine deleterious missense mutations in ARMC5, one of which weakened the interaction between ARMC5 and RPB1. The enlarged Pol II pool in Armc5 KO neural precursor cells (NPCs) influenced a particular group of genes, some of which (e.g., Folh1) are thought to be involved in the development of the neural tube. In summary, ARMC5 and CUL3 form an E3 complex, which targets RPB1 causing its ubiquitination and degradation. In the absence of such a mechanism, there is a disturbance of RNA polymerase II homeostasis, which leads to a decrease in the T cell-mediated immune response, the development of PBMAH and an increased risk of neural tube defects.
268

An Introductory Course in the Reading of Simple Graphic and Statistical Material for Use in Junior High Schools

McKenzie, Annie 01 January 1930 (has links) (PDF)
In the stories of olden times and in those of our own American Indians, we learned of the picture writing of primitive peoples. It became an early method of recording people's thoughts. This was a very useful method at a time when the race was young. This in turn was the beginning of our alphabet, later the beginning of shaping letters into words, and then word into sentences and paragraphs. As our world has grown older, new idea have come into use and we are no longer content to live as our grandparents lived. We travel by fast express trains, high powered auto- mobiles, airplanes, or zeppelins. The radio gives us the news before our papers containing it are on the street. are not able to talk with people on the other side of the world. Business men find this a very valuable means of doing business when time means money. The motion pictures bring us the story of the book we have not had time to read and the characters from its pages talk to us from the screen. In short, we must have quicker ways of doing things.

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