Orientador: Celso Valentim Santilli / Banca: Leila Aparecida Chiavacci Favorin / Banca: Eduardo Ferreira Molina / Resumo: Neste trabalho a metodologia sol-gel foi utilizada para a preparação de materiais híbridos orgânico-inorgânicos (HOI) à base de óxido de poli-etileno (PEO), ligado de forma covalente com o agente acoplador 3(isocianatopropil) - trietoxisilano (IsoTREOS) conjugados com um material zeolítico do tipo MFI, visando aplicações como catalisador para a reação de acetilação do glicerol e assim agregar valor a esse coproduto gerado na produção do biodiesel. O objetivo desta dissertação é demonstrar que o sinergismo entre híbridos do tipo siloxano-poliéter e as zeólitas pode ser explorado na produção de hidrogéis com atividade catalítica. As análises por Microscopia Eletrônica de Varredura (MEV) evidenciaram a homogeneidade na dispersão do material zeolítico na matriz híbrida Os difratogramas de raios-X apresentaram os picos característicos da estrutura cristalina da zeolita ZSM-5 após a conjugação com a matriz U-PEO. Os resultados de Calorimetria Diferencial de Varredura (DSC) revelaram que não ocorre uma mudança significativa na temperatura de transição vítrea (Tg), após a conjugação da matriz híbrida com a zeólita e revelaram uma diminuição do pico endotérmico associado à fusão dos domínios cristalinos do PEO1900, indicando uma possível interação matriz-zeólita. As análises por Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) confirmaram a interação entre a matriz híbrida e a zeólita pelo deslocamento das bandas associadas ao oxigênio tipo éter não coordenado. Medid... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work the sol-gel methodology was used for the preparation of organic-inorganic hybrid (HOI) materials based on polyethylene oxide (PEO) - covalently bonded with the coupling agent 3 (isocyanatopropyl) triethoxysilane (IsoTREOS) conjugate with a zeolitic material of the MFI type, aiming at applications as catalyst for glycerol acetylation reaction and thus add value to this byproduct generated in biodiesel production. The objective of this dissertation is to demonstrate that the synergism between siloxane-polyether hybrids and zeolites can be explored in the production of catalytic activity hydrogels. Scanning Electron Microscopy (SEM) analyzes showed homogeneity in the dispersion of zeolite material in the hybrid matrix. XDR patterns showed the characteristic peaks of the ZSM-5 zeolite crystal structure after conjugation with the U-PEO matrix. Differential Scanning Calorimetry (DSC) results revealed that no significant change in glass transition temperature (Tg) occurs after conjugation of hybrid matrix with zeolite and revealed a decrease in endothermic peak associated with fusion of crystalline domains of PEO1900., indicating a possible matrix-zeolite interaction. Fourier Transform Infrared Spectroscopy (FTIR) analyzes confirmed the interaction between the hybrid matrix and zeolite by shifting the bands associated with uncoordinated ether oxygen. Small-angle X-ray Scattering (SAXS) measurements showed that the starting reagents in the solketal production reaction w... (Complete abstract click electronic access below) / Mestre

In Deutschland werden jährlich über 40 Millionen männliche Eintagsküken aus Legelinien aufgrund vorrangig wirtschaftlicher Interessen getötet. Dies stellt sowohl ein ethisches als auch ein tierschutzrechtliches Problem dar (ANON. 2006, IDEL 2007). Gerade vor dem Hintergrund aktueller politischer Entscheidungen (MUNLV NRW 2013, NI MELV 2014) besteht ein Bedarf an Alternativen zur Tötung männlicher Eintagsküken. Verschiedene Lösungsansätze wie z. B. das Zweinutzungshuhn (ICKEN et al. 2013) oder aber die Mast männlicher Geschwisterhühner (KAUFMANN und ANDERSSON 2013) sind derzeit aus ökonomischen und ökologischen Gründen nicht flächendeckend realisierbar. Eine weitere Möglichkeit bietet die In-ovo-Geschlechtsbestimmung. Hierbei wird das embryonale Geschlecht bereits vor dem Schlupf identifiziert; nachfolgend können die Eier mit männlichen Embryonen aussortiert werden. Um sowohl ethischen als auch tierschutzrechtlichen Aspekten Genüge zu tun, sollte die Geschlechtsidentifikation dabei vor Einsetzen des embryonalen Schmerzempfindens stattfinden (Tag 10 + 12 h der Bebrütung; CLOSE et al. 1997). Ziel der vorliegenden Arbeit war die Entwicklung einer verlässlichen Methode zur In-ovo-Geschlechtsbestimmung anhand geschlechtsspezifischer Differenzen im Hormongehalt der Allantoisflüssigkeit sieben bis zehn Tage alter Hühnerembryonen. Nachfolgend wurde der Einfluss der Geschlechtsbestimmung auf die embryonale Entwicklung, Schlupferfolg, Aufzucht sowie die Leistungsparameter der adulten Tiere analysiert. Im Rahmen der ersten Teilstudie erfolgte die Beprobung von n = 750 Eiern des Braunlegehybrids Lohmann Brown (LB, Lohmann Tierzucht GmbH, Deutschland). Der minimalinvasiven Entnahme von Allantoisflüssigkeit folgte die Untersuchung auf 17β-Östradiol (E2), Östronsulfat (E1S) und Testosteron mittels an das Haushuhn angepassten Enzymimmunoassays (ELISA). Es konnten sowohl für E2 als auch für E1S signifikante (p < 0,01) geschlechtsspezifische Differenzen in der Allantoisflüssigeit von neun und zehn Tage alten Embryonen nachgewiesen werden. Die Testosteronkonzentration hingegen zeigte an keinem der untersuchten Tage geschlechtsabhängige Unterschiede und erwies sich somit für die In-ovo-Geschlechtsbestimmung als ungeeignet. Die statistische Auswertung ergab, dass die Bestimmung von E1S eine frühere und genauere Geschlechtsidentifikation ermöglicht als die von E2. Der für E1S festgelegte Grenzwert erreicht bei neun Tage alten Embryonen eine 86%ige Sensitivität und 83%ige Spezifität. In der zweiten Teilstudie wurde die zuvor etablierte Technik der Geschlechtsbestimmung mittels E1S an 8 + 4 h (n = 2420) und 9 + 4 h (n = 2850) Tage alten Embryonen der Herkunft LB sowie an n = 150 9 + 4 h alten Embryonen des Weißlegehybrids Lohmann Selected Leghorn (LSL, Lohmann Tierzucht GmbH, Deutschland) überprüft. Das Geschlecht der 8 + 4 h Tage alten Embryonen konnte zu 84 % korrekt identifiziert werden. Dieser Wert stieg bei 9 + 4 h Tage alten Embryonen auf 98 % (LB) bzw. 100 % (LSL) an. Im Vergleich zu einer unbehandelten Kontrollgruppe (n = 5258) wurde die Schlupfrate durch die Entnahme von Allantoisflüssigkeit um 1,4 - 3,5 (LB) bzw. 12,7 Prozentpunkte (LSL) reduziert. Nachfolgend wurden 150 Tiere der Versuchsgruppe und 80 Tiere der Kontrollgruppe für eine Aufzuchtperiode von 17 Wochen eingestallt. Hierbei zeigten sich hinsichtlich des Körpergewichtes signifikante (p < 0,05) Unterschiede zwischen Versuchs- und Kontrollgruppe in Woche 4 und 6, wobei die Zunahmen in der Versuchsgruppe geringer waren. Anschließend wurde die Leistung von 120 Tieren der Versuchsgruppe und 60 Tieren der Kontrollgruppe bis Lebenswoche 33 bezüglich Legeleistung, Eigewicht, Körpergewicht sowie Futterverbrauch analysiert. Bei keinem der untersuchten Parameter konnten signifikante Unterschiede zwischen den Gruppen festgestellt werden (p > 0,05). Die Resultate der vorliegenden Arbeit zeigen, dass eine verlässliche Geschlechtsbestimmung in ovo bei 9 + 4 h Tage alten Hühnerembryonen mithilfe einer Bestimmung der E1S-Konzentration in der Allantoisflüssigkeit möglich ist; zudem ist die beschriebene Methode bei verschiedenen Legelinien anwendbar. Die Entnahme von Allantoisflüssigkeit führt zwar zu einer minimalen Reduktion der Schlupfrate, bei adulten Legehennen kommt es jedoch zu keiner Beeinträchtigung der Produktionsleistung. Demnach erfüllt das etablierte Verfahren alle Grundvoraussetzungen für eine Anwendung in kommerziellen Brütereien. Da die Geschlechtsbestimmung vor Einsetzen des embryonalen Schmerzempfindens erfolgt, kann sie somit als Grundlage für eine ethisch vertretbare Alternative zum Töten männlicher Eintagsküken angesehen werden. / In Germany about 40 million day-old male chicks are culled each year predominantly because of economic reasons. From the animal welfare as well as the ethical point of view this is a problematic situation (ANON. 2006, IDEL 2007). Particularly with regard to current political decisions (MUNVL NRW, NI MELV 2014) alternatives to the culling of male day-old chicks are required. Different approaches such as a dual-purpose breed (ICKEN et al. 2013) or the fattening of male layer-hybrids (KAUFMANN and ANDERSSON 2013) are not ubiquitous marketable at present due to economic and ecological reasons. In ovo sexing represents another option; the embryonic gender is determined before hatch and the eggs containing male embryos can be eliminated subsequently. To comply with ethical and animal welfare aspects, the sexing should take place before the onset of embryonic pain perception (embryonic day 10 + 12 h; CLOSE et al. 1997). Aim of this thesis was the development of a reliable method for in ovo gender identification with the help of sex-specific differences in the hormone concentration of the allantoic fluid of seven to ten day old chick embryos. Subsequently, the influence of gender identification on embryonic development, hatching rate, rearing as well as production performance of the adult hens was analysed. Within the first study n = 750 eggs of the brown layer-hybrid Lohmann Brown (LB; Lohmann Tierzucht GmbH, Germany) were sampled for allantoic fluid. After the minimally invasive withdrawal the allantoic fluid was analysed via enzyme immunoassays (ELISA) adapted to domestic chicken for 17β-oestradiol (E2), oestrone sulphate (E1S) and testosterone. With regard to E2 and E1S, significant (P < 0.01) sex-specific differences were observed in the allantoic fluid of nine and ten day old embryos. Testosterone on the other hand displayed no gender-related variances on any of the analysed days. Therefore, it proved to be unsuitable for gender identification using the method applied in this study. Statistical analysis showed that the analysis of E1S allows an earlier and more accurate sexing than the E2-assay. The limit value determined for E1S has a sensitivity of 86 % and a specificity of 83 % for nine day old embryos. The previously established method for gender identification via E1S detection in the allantoic fluid was verified with a larger number of samples in the second study. The allantoic fluid of day 8 + 4 h (n = 2420) and day 9 + 4 h (n = 2850) old LB embryos as well as n = 150 day 9 + 4 h old embryos of the white layer-hybrid Lohmann Selected Leghorn (LSL; Lohmann Tierzucht GmbH, Germany) was analysed. For day 8 + 4 h old embryos the sex was correctly identified in 84 %. The accuracy of gender prediction increased for day 9 + 4 h old embryos up to 98 % (LB) and 100 % (LSL). Compared to an untreated control group (n = 5258) sampling of allantoic fluid reduced the hatching rate by 1.4 - 3.5 (LB) and 12.7 points of percentage (LSL). In the following, 150 animals of the experimental group and 80 animals of the control group were reared for a period of 17 weeks. With regard to the body weight significant differences (P < 0.05) were observed in weeks 4 and 6, with the animals of the experimental group having a lower body weight. Subsequently the production performance of 120 hens from the experimental and 60 hens from the control group was analysed up to an age of 33 weeks. With respect to egg production, egg weight, body weight and feed consumption no significant differences (P > 0.05) were observed between the groups. The results of this thesis demonstrate that a reliable in ovo sexing of day 9 + 4 h old chicken embryos is possible via the measurement of E1S in the allantoic fluid; additionally the method is not limited to a certain layer strain. The sampling of allantoic fluid reduces the hatching rate only marginally. The production performance of adult hens on the other hand is not affected. Therefore, the described technique fulfils all the basic requirements for an alternative method to the culling of day-old male layer chicks. Because gender identification takes place before the onset of embryonic pain perception it can serve as the basis for an ethical alternative to the culling of male day-old chicks from layer-hybrids.

Background: Rising global uncertainty and volatility have changed how businesses envision themselves and their future. Particularly Social Business Hybrids emphasize the importance of purpose beyond profit. Their aim is to develop a more inclusive and green economy by pursuing and creating both financial and social value. This aim, however, comes with the risk of mission drift, meaning that the organization could prioritize one value at the expense of the other. As this is an emergent strategic dilemma in the field of social entrepreneurship, it is prudent to find ways to manage the risk of mission drift. In this context, considerable attention has to be given to the question of how employees of Social Business Hybrids manage the risk of mission drift, as their viewpoint has mostly been neglected by prior scholarship. Purpose: The purpose of the present study is to provide an understanding of why the management of mission drift is relevant for Social Business Hybrids and to give new insights into perspectives that employees of Social Business Hybrids have towards tactics and strategies that support successful management of mission drift. By researching the critical role that employees play as stakeholders in the context of mission drift management, we aim to enrich current literature by deriving new insights into strategies that can help Social Business Hybrids successfully balance their dual objectives. Method: This study is based on: Qualitative, inductive research; Ontology – Relativism; Epistemology – Social Constructionism; Methodology – Grounded Theory; Data Collection – 12 semi-structured in-depth Interviews; Sampling – Purposive, Snowball; Data Analysis – Grounded Analysis  Conclusion: In our findings, we ascertained distinct sources that anticipate a risk for mission drift. Further, we identified detailed tactics that can significantly support the management of mission drift. Finally, resulting from the findings, a framework was developed, that proposes five distinctive overarching strategies, which are enabled by two underlying mechanisms that employees in Social Business Hybrids apply to manage mission drift.

In dieser Arbeit werden die Unterschiede in der Genuskongruenz der belebten Substantive zwischen den ein- und zweisprachigen russischen Muttersprachlern und Muttersprachlerinnen mit Hilfe einer empirischen Studie untersucht. Speziell werden die vier Sonderfälle betrachtet: Hybridnomen (z.B., doktor „Arzt/Ärztin“), Substantive der dualen Genera (z.B., sirota „Waise“), weibliche Vornamen in der Verkleinerungsform mit den Suffixen –ik/ -ok (z.B., Irch-ik), Substantive, die männliche Personen bezeichnen, aber deren Form mit einem Vokal endet. Die Analyse der Ergebnisse dieser Studie ergibt folgende Feststellungen. Die fortgeschrittenen russischen Herkunftssprecher/-innen können mit den grammatischen Strukturen, die keine Variabilität darstellen – d.h. mit den Substantiven der dualen Genera und mit männlichen Personenbezeichnungen mit femininen Endungen - das Niveau eines/einer Muttersprachlers/Muttersprachlerin erreichen. Mit den Substantiven, die variable Genuskongruenz erlauben (weibliche Vornamen mit Suffixes –ik/-ok, Hybridnomen) wurde eine verdeckte Restrukturierung der Sprache beobachtet. Die Sprecher/-innen nutzen die grammatischen Strukturen ohne sichtbare Fehler, aber trotzdem anders als es die Muttersprachler/-innen tun würden. Im Fall der Nutzung der gemischten Kongruenz liegt die Restrukturierung daran, dass die Herkunftssprecher/-innen das generische Maskulinum nicht erwerben. Es sollte jedoch beachtet werden, dass die Nutzung der Genuskongruenz stark vom Sprachniveau eines/einer Sprechers/Sprecherin abhängt. Außerdem wurde festgestellt, dass Referentialität eine besondere Schwierigkeit für die Herkunftssprecher/-innen darstellt. Was die einsprachigen Muttersprachler/-innen angeht, wird es gezeigt, dass die Abhängigkeit dieser Sprecher/-innen bei der Wahl der Genuskongruenz von dem lexikalischen Kriterium die Tendenz der russischen Sprache zum analytischen Sprachbau beweist. / In this dissertation, I raise the issue of the grammatical gender in Russian as a heritage language. In particular, this thesis aims to determine the major principles of use of gender agreement patterns with the four classes of exceptional nouns (hybrids referring to females, common gender nouns, female names ending in -ik/ -ok, male terms and male names ending in -a/ -ja) in heritage Russian. For this purpose, I have conducted an experimental study on gender agreement, which consists of two big tasks, a translation task and a multiple-choice task. A detailed analysis of the results of the study has led to the following conclusions. Advanced heritage speakers are able to achieve the target-like language proficiency in gender agreement in transparent contexts and in some situations of form-meaning mismatch. The use of agreement patterns strongly depends on the speakers’ language proficiency. Less proficient speakers tend to have more problems with referential nouns. Importantly, this dissertation provides evidence for the importance of variability for successful heritage language acquisition. Variability of grammatical structures leads to inconsistency of input which makes it harder for heritage speakers to acquire these structures and leads to incomplete acquisition. As a result, heritage speakers fail to acquire the generic component of the semantic structure of hybrid nouns. This in turn results in the divergence in the use of agreement patterns by monolingual and bilingual speakers with the exceptional nouns, which allow variability (hybrids, female names ending in -ik/ -ok). This divergence is realised without overt errors and represents an example of covert language restructuring. Apart from that, the thesis touches upon the question of the development of standard Russian and provides evidence for the increase of analytic features in the Russian language.

Le développement d’agents anticancéreux s’étend de la découverte d’une cible thérapeutique à la commercialisation du médicament. La chimie médicinale intervient dans la conception et la synthèse de molécules. Les essais réalisés in vitro puis in vivo sont ensuite déterminants pour évaluer le mode d’action, l’efficacité et la sélectivité du principe actif. À cette étape, si une molécule n’est pas sélectionnée, son étude s’arrête. Afin de tirer profit du temps et de l’argent investis dans son développement, des stratégies s’inspirant de ces composés peuvent être utilisées, en modifiant leur structure afin d’améliorer leur efficacité. La première méthode exploitée ici consiste à synthétiser des molécules bifonctionnelles, incorporant le pharmacophore du principe actif d’intérêt, ainsi qu’un ligand capable d’induire la dégradation de sa cible. Ces molécules sont appelées AUTAC ou PROTAC, selon le mode de dégradation induit, soit l’autophagie ou la protéolyse. La deuxième méthode repose sur le développement de molécules hybrides, capables d’interagir avec différentes cibles. Deux principes actifs sont alors liés de manière covalente afin de synthétiser une nouvelle molécule dont les propriétés pharmacocinétiques diffèrent. L’hybride pourrait être ainsi plus efficace, cumulant les activités de ses deux ligands de base. Pour viser les cellules cancéreuses, une stratégie attrayante est le ciblage de certaines voies métaboliques. L’ATP étant une source d’énergie essentielle pour l’intense prolifération des cellules cancéreuses, réduire sa production en ciblant la phosphorylation oxydative dans la mitochondrie et la glycolyse peut être un traitement efficace. Les dérivés de biguanides, comme la metformine, sont connus pour inhiber la phosphorylation oxydative. Par ailleurs, le NAD+ étant un cofacteur nécessaire à de nombreux processus biologiques essentiels, notamment la glycolyse, diminuer sa production peut alors induire des effets anticancéreux. De nouveaux dérivés de biguanides et d’inhibiteurs de la NAMPT sont donc synthétisés afin de développer des molécules bifonctionnelles ciblant le métabolisme des cellules cancéreuses. / The development of new anticancer agents covers all the steps from the discovery of a target to the commercialisation of a drug. Medicinal chemists are responsible for the design and synthesis of molecules but the future of the drug relies on their activity in vitro and in vivo. However, compounds that failed because of their lack of efficiency or selectivity can be reused to take advantage of the time and money invested on their development. To develop more potent drugs, these compounds can be modified using different strategies. One of them consists in synthesising bifunctional molecules, also called chimeras, incorporating a pharmacophoric moiety from the drug and a ligand inducing its target’s degradation. These molecular degraders are named according to the mode of degradation involved: AUTAC for Autophagy Targeting Chimera or PROTAC for Proteolysis Targeting Chimera. Another strategy is to design a dual targeting agent based on two different drugs bound covalently. The resulting hybrid is then able to interact with each ligand’s target but exhibits a new pharmacokinetic profile that might increase its efficiency. Targeting cancer cell metabolism is an attractive strategy that can be applied to many different types of cancer. Since ATP is the main energy source of the cells, its production is necessary to insure the intense proliferation rate of cancer cells. Targeting the oxidative phosphorylation in mitochondria and the glycolysis, the two main ways to produce ATP, can be effective to inhibit the proliferation of cancer cells. Biguanides derivatives such as metformin are known to inhibit OXPHOS. Furthermore, NAD+ being an essential cofactor involved in many biological processes including glycolysis, targeting its production by the NAD salvage pathway allows the discovery of effective anticancer agents. New biguanides and NAMPT inhibitors derivatives are thus synthesized for the development of bifunctional molecules targeting the energy metabolism of cancer cells.

International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / The use of hardware security for telemetry in satellites utilized for intelligence and defense applications is well known. Less common is the use of hardware security in ground-based computers hosting applications that post process telemetry data. Analysis reveals vulnerabilities in software only security solutions that can result in the compromise of telemetry data housed on ground-based computer systems. Such systems maybe made less susceptible to compromise with the use of hardware based security.

Developing new materials with desired properties is a vital component of emerging technologies. Functional hybrid compounds make an important class of advanced materials that let us synergistically utilize the key features of the organic and inorganic counterparts in a single composite, providing a very strong tool to develop new materials with ”engineered” properties. The research presented here, summarizes efforts in the development of facile and efficient methods for the fabrication of three- and two-dimensional inorganic-organic hybrids based on layered oxide perovskites. Microwave radiation was exploited to rapidly fabricate and modify new and known materials. Despite the extensive utilization of microwaves in organic syntheses as well as the fabrication of the inorganic solids, the work herein was among the first reported that used microwaves in topochemical modification of the layered oxide perovskites. Our group specifically was the first to perform rapid microwave-assisted reactions in all of the modification steps including proton exchange, grafting, intercalation, and exfoliation, which decreased the duration of multi-step modification procedures from weeks to only a few hours. Microwave-assisted grafting and intercalation reactions with n-alkyl alcohols and n-alkylamines, respectively, were successfully applied on double-layered Dion-Jacobson and Ruddlesden-Popper phases (HLaNb2O7, HPrNb2O7, and H2CaTa2O7), and with somewhat more limited reactivity, applied to triple-layered perovskites (HCa2Nb3O10 and H2La2Ti3O10). Performing neutron diffraction on n-propoxy-LaNb2O7, structure refinement of a layered hybrid oxide perovskite was then tried for the first time. Furthermore, two-dimensional hybrid oxides were efficiently prepared from HLnNb2O7 (Ln = La, Pr), HCa2Nb3O10, HCa2Nb2FeO9, and HLaCaNb2MnO10, employing facile microwave-assisted exfoliation and post-exfoliation surface-modification reactions for the first time. A variety of surface groups, saturated or unsaturated linear and cyclic organics, were successfully anchored onto these oxide nanosheets. Properties of various functionalized metal-oxide nanosheets, as well as the polymerization of some monomer-grafted nanosheets, were then investigated for the two-dimensional hybrid systems.

I pull from what I see in my urban surroundings. There is always a sense of dread fused with optimism that prevails. Is it beautiful? Fragments of low-riders and tricked-out cars become symbols of desire and the glowing red lens of a stop light becomes a Cyclops poised to defend his garden. Candy-coated, blooming, dripping and seductively slick confronts you with the obvious warning: STOP! You could be next… …The grass really is greener on The Other Side of the Fence. At least until winter comes.

Les objectifs du travail présenté ici sont de comprendre les procédés de formulation des gouttelettes et des particules afin de faire des hybrides polymère-polymère de qualité en dispersions aqueuses et d’utiliser notre compréhension fondamentale de ces procédés pour : 1. Augmenter le taux de conversion de(s) monomère(s) autant que possible. 2. Comprendre l’impact de ces procédés sur les propriétés des films hybrides. Des cas particuliers ont été étudiés dans des conditions commercialement viables (taux de solide de 50% en masse) basés sur deux systèmes appelés alkyde-acryliques et polyuréthane-acrylique. La préparation des miniémulsions, la polymérisation en miniémulsion et la caractérisation des latex hybrides, l’incorporation chimique d’alkyde et de polyuréthane dans les monomères acryliques ont été étudiés en détails. Nous sommes parvenus à synthétiser et caractériser des latex hybrides avec de haut taux de solides (50% en masse) composés de particules de 100nm de diamètre utilisables dans des applications de revêtement et d’adhésifs / The objectives of work presented in this thesis are to understand droplet and particle formulation processes in order to make useful polymer-polymer hybrids in aqueous dispersions and use our fundamental understanding of these processes to: 1. Improve monomer conversion as much as possible. 2. Understand impact of these processes on hybrid film properties. Specific case studies of interest under commercially feasible conditions (i.e. solids content of 50wt %) were done based on two systems namely alkyd-acrylic and polyurethane-acrylic. Miniemulsification, miniemulsion polymerisation and characterisation of hybrid latex, chemical incorporation of alkyd and polyurethane to acrylic monomers were studied in detail. We have been able to successfully synthesise and characterise hybrid latex of about 100nm in particle diameter and high solids content (50wt %) to be used in coating and adhesive applications

Two of the most pervasive threats to species biodiversity are invasive species and habitat loss and degradation. Invasive species are often relatively insensitive to disturbance and many expand their range into disturbed and fragmented habitats. This dissertation uses an interdisciplinary approach to investigate how anthropogenic habitat disturbance is precipitating a range expansion in an invasive toad species, Bufo nebulifer, which is driving a decline in its native congener, B. fowleri. I employed a remote sensing and GIS study using historical data to compare changes in the two species distributions and habitat changes, a molecular genetic study to identify interspecific hybrids and their potential effects on the parental species, and an experimental ecology study to look at the effects of competition and predation on the two species. The results of the landscape level analyses of species' distributional changes in different disturbance levels showed that both species' distributions have changed significantly. The distributions of the two species are inversely affected by habitat disturbance; the distribution of B. fowleri in highly degraded habitat has contracted while the expansion of B. nebulifer increased substantially. The molecular genetic study successfully demonstrated the use of nuclear and mitochondrial markers to identify cryptic hybrids and their maternal lineage. Three hybrids were detected using nuclear introns and a morphologically cryptic hybrid was identified using mitochondrial DNA as the progeny of a cross that was previously thought to be inviable. Although relatively few hybrids were currently found, the identification of a cryptic hybrid implies that the rate of historical hybridization may have been drastically underestimated. Ecological studies showed that competition with B. nebulifer tadpoles had a negative effect on both body size measures and survival to metamorphosis for B. fowleri tadpoles. The addition of predators to experiment did not favor the survival of B. fowleri over B. nebulifer. Bufo fowleri's inability to compete with its invasive congener could be a driving mechanism for the decline of B. fowleri and the expansion of B. nebulifer. The methods discussed in this dissertation offer promising and practical new approaches for evaluating and managing changes in the distribution of species of conservation concern.