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Submitted by Samara Zanetti (samarazanetti@hotmail.com) on 2016-11-09T17:14:52Z No. of bitstreams: 1 Dissertação final.pdf: 1425092 bytes, checksum: 77869aab1560a58921ae52b649d3da9d (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO null (luizaromanetto@hotmail.com) on 2016-11-16T12:20:36Z (GMT) No. of bitstreams: 1 zanetti_s_me_bot.pdf: 1425092 bytes, checksum: 77869aab1560a58921ae52b649d3da9d (MD5) / Made available in DSpace on 2016-11-16T12:20:36Z (GMT). No. of bitstreams: 1 zanetti_s_me_bot.pdf: 1425092 bytes, checksum: 77869aab1560a58921ae52b649d3da9d (MD5) Previous issue date: 2016-07-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O trabalho teve como objetivo avaliar as respostas morfológicas, anatômicas e nutricionais da mandioca de mesa em diferentes fases de crescimento da cultura sob condições de déficit hídrico. O experimento foi conduzido por um ano sob cultivo protegido no Faculdade de Ciências Agronômicas, Campus de Botucatu, em delineamento experimental inteiramente casualizado, com esquema fatorial 3 x 3, constituído de três fases de crescimento (90 a 180 DAP; 180 a 270 DAP e 270 a 360 DAP) da cultivar de mandioca de mesa IAC 576-70 e três tensões de água no solo ( -10, -40 e -70 kPa). As manivas-sementes com 5 a 7 gemas foram plantadas em caixas com capacidade de 500 L, sendo irrigadas diariamente, mantendo o solo na capacidade de campo até o início das fases. Aos 0, 20, 40, 60 e 80 dias após o início do déficit foram avaliados a altura de planta, o diâmetro do caule, o número de folhas por planta, a área foliar total e o índice de área foliar. As folhas da mandioca foram analisadas quanto a sua estrutura anatômica aos 150 dias após o plantio. Foram realizadas avaliações nutricionais aos 180, 270 e 360 dias após o plantio. No momento da colheita avaliou-se a massa da matéria seca da parte aérea (folhas + haste), da cepa, das raízes tuberosas e fibrosas; o comprimento e diâmetro das raízes tuberosas; o número de raízes; o índice de colheita; a razão de área foliar e a produtividade. As fases de crescimento 90 a 180 DAP e 270 a 360 dias após o plantio (DAP) foram influenciadas pelas tensões de água no solo, proporcionando reduções em todas as variáveis morfológicas e nos componentes de produção. A anatomia das folhas apresentou modificações como diminuição das espessuras do mesofilo, do parênquima lacunoso, da epiderme abaxial, e do número de elemento de vasos, e aumento da espessura e diâmetro dos elementos de vaso. Houve diminuição no teor de K nas fases de 90 a 180 e 270 a 360 DAP e aumento de P e Mg nas três fases, e Fe e Zn aos 90 a 180 DAP. A produtividade final das raízes tuberosas foi afetada pelas tensões de água no solo (-40 e -70 kPa) nas fases de 90 a 180 e 270 a 360 após o plantio. / This research aimed to evaluate the morphological, anatomical and nutritional responses of sweet cassava in different growth stages of the crop under water deficit. The experiment was carried out for a year in a greenhouse at the Faculty of Agricultural Sciences, Botucatu, in a completely randomized design in factorial scheme 3 x 3, consisting of three growth stages (90-180 DAP, 180-270 DAP and 270-360 DAP) of cultivating sweet cassava IAC 576-70 and three water tension in the soil (-10, -40 and -70 kPa). The stem cuttings with 5-7 nodes of the cultivar IAC 576-70 were planted in boxes with 500 liters capacity, keeping soil moisture at field capacity until the beginning of the phases. At 0, 20, 40, 60 and 80 days after the beginning of the deficit were measured the plant height, stem diameter, number of leaves per plant, total leaf area and leaf area index. Cassava leaves were analyzed for their anatomical structure at 150 days after planting. It were nutritional evaluations performed at 180, 270 and 360 days after planting, and at harvest evaluated the dry matter of the shoot (leaves + stem), the strain of tuberous and fibrous roots; the length and diameter of the tuberous roots; the number of roots; harvest index; the leaf area ratio and productivity. The growth phases 90 to 180 and 270 to 360 days after planting (DAP) were influenced by the water tension in the soil, providing reductions in all morphological variables and production components. The anatomy of the leaves showed changes as the decrease of the thickness of mesophyll, of the spongy parenchyma, epidermal abaxial, and of the vessels element number and increasing the thickness and diameter of vessel elements. There was a decrease in K content in phases 90180 and 270-360 DAP and increase of P and Mg in three phases, and Fe and Zn to 90-180 DAP. The final yield of tuberous roots were affected by the tensions in water (-40 to -70 kPa) in the phases 90-180 and 270-360 after planting.

Context: Start-ups have recently emerged as an operational model for small and newly-founded firms globally. This increasing business acceptance is present within the European markets, as well as within the Greek. Researchers also complied to the ”commands” of the industry and startup research followed the same, to practice, increasing course. Although the increase in both research and practice is visible, and the fact that several start-up related topics are well-documented, the start-up literature still shows certain limitations that need to be answered. Theory: This study performs an extensive review of the start-up literature, provides definitions and descriptions of key start-up characteristics, and identifies the main streams, and limitations of start-up research, as long as cases of actual start-ups within the Greek business reality. Purpose: The purpose of this study is to provide insight on certain literature limitations by examining start-up customs towards collaboration and openness initiatives and activities. More in detail, the study aims to identify whether start-ups are able to collaborate (newness and smallness paradox), what is the extent (breadth and depth, partner variety, and collaboration content) of their collaboration and openness customs with different partners, but also the individual importance of specific partners, and the ways this importance changes through different phases of the start-up growth. Also, documented matters such as the determinants of collaborations and the internal organizational structure of start-ups towards openness and collaborations are also discussed. Design/Methodology/Approach: A multiple-case study that follows the replication logic is performed. The study focuses on six Greek online start-ups, and extracts information initially from the websites of the firms, and then by interviewing one key employee in each start-up. The combined information from each case are cross-analysed so as behavioural patterns to emerge and conclusions to be drawn regarding start-up initiatives and activities towards collaboration and openness. Findings: Start-ups are indeed able to collaborate and practice openness with external partners from the beginning, while the collaboration and openness is closely related to the desired outcome/collaboration content that fulfils a specific need. This desired outcome is connected to the extent – breadth and depth – of the collaboration, but also to the type of each partner. Thus, startups closely collaborate with few and selected partners of each kind (e.g. universities, supplies etc.), with the exception of customers and users. The collaboration with customers and users is wide and limited on their feedbacks due to their numbers. Customers, users, suppliers, innovation intermediaries, and universities were identified as the most important partners to start-ups. The importance of these partners is connected to the start-up growth lifecycle. Innovation intermediaries are the most important startup partners, while customers, users and suppliers are important from the stabilization phase and during the whole start-up lifecycle. Universities importance were not found to be clearly connected to the startup growth phases, but mostly to the collaboration content. Regarding the importance, some differences might occur amongst start-ups active in different industries. Those differences are industry specific and affect how and when each start-up collaborates with different partners. Finally, this study confirmed the propositions of previous studies regarding the determinants and internal organizational structure towards collaboration and openness with external partners. Research limitations and implications: Although the present study shows a set of limitations mostly regarding the number and distribution of the cases, it is the authors’ belief that it also shows a set of theoretical and practical implications. It provides managers and researchers with findings on uncharted territories in start-up literature, it connects its findings to prior start-up research, and provides insight on the almost undeveloped literature on Greek start-ups.

Bakgrund och problemdiskussion: Mikro- och småföretag har fått en allt större betydelse för sysselsättningen och den ekonomiska tillväxten i Sverige. 22.6 % av Sveriges företag klassificeras som mikroföretag och denna storleksklass har svårt att växa vidare. I denna storleksklass är viljan att växa vidare god, dock avtar den då antalet anställda inom en organisation ökar. Detta då komplexiteten att styra och kontrollera företaget ökar. När ett företag växer ökar behovet av formell ekonomistyrning och att utveckla det kommer främja ett företags långsiktiga tillväxt. Att inte införa formell ekonomistyrning kan orsaka att ett företag inte uppnår dess fulla tillväxtpotential och kan medföra stor skada inom ett företag. Syfte: Det övergripande syftet är att utveckla en konceptuell modell som beskriver och förklarar behovet av formell ekonomistyrning hos mikroföretag i tillväxt, vilket ska möjliggöras genom två delsyften. Metod: En kvalitativ forskningsansats med flerfallstudie ansågs lämplig för studiens forskningsfråga och syfte. För empiriinsamling valdes semi-strukturerade intervjuer och dokument. Slutsats: Behovet av att införa formell ekonomistyrning tilltar under ett företags tillväxt. I uppstarten behövs det för att ett företag ska överleva, sälja och ha möjlighet att utveckla en produkt. Vid ökad efterfråga växer behovet av formell ekonomistyrning för att kontrollera tillväxten och möjliggöra arbete mot de uppsatta målen. Under ett företags utveckling utökas dess organisation vilket ökar behovet av att vidareutveckla den formella ekonomistyrningen. / Background and discussion: Micro- and small enterprises have become increasingly important for the employment and economic growth in Sweden. 22.6 % of the Swedish companies are classified as micro-enterprises, and this size class has difficulties to grow on. The desire to continue to grow in this size class is good, however it decreases as the number of employees within an organization increases. This is because the complexity of managing and controlling the company increases. When a company grows, the need for formal management control increases and to develop it will promote a company’s long-term growth. To not introduce formal management control may cause the company to not achieve its full growth potential and can also cause great damage within a company. Purpose: The overall purpose is to develop a conceptual model that describes and explains the need for formal management control of micro-enterprises in growth, which will be enabled through two smaller purposes. Method: A qualitative approach with a multiple case study was considered appropriate for the study’s research question and purpose. For empirical data collection was semi-structured interviews and documents selected. Conclusion: The need to establish formal management control increases during a company’s growth. In the start-up is it needed for a company to survive, to sell and have the opportunity to develop a product. In case of increased demand is the need for formal management control growing to control the growth and facilitate work towards the established goals. During the development of the company its organization expands, which increases the need to further develop the formal management control.

Pathogenesis originating from mycobacterial invasion on host cells is prevalent and is a major challenge in efforts towards overcoming the burden of mycobacterial diseases. Complex architecture of mycobacterium cell wall includes an assortment of glycolipids, phospholipids, glycopeptidolipids (GPLs), peptidoglycans, arabinogalactans, lipoarabinomannans and mycolic acid. Aided by thick cell wall envelope, mycobacteria are known to survive in hostile environment. As most antibiotics target the log phase of the bacteria, bacterial survival is also largely dependent on its stationary phase. Mycobacteria have evolved colonization by means of biofilm formation in the stationary phase, so as to survive under stress and hostile conditions. Biofilms are the specialized form of phenotype which makes bacteria several fold resistant to antibiotics. Development of inhibitors against biofilms remains a challenge due to the poor permeability of molecules and coordination among cells. The first part of Chapter 1 of the thesis describes the details of formation of biofilm in the stationary phase of bacteria and understanding the molecular level details for making the strategies to overcome antidrug resistance of mycobacteria. Among the cyclic hosts, cyclodextrins are prominent. Due to their unique structural and physical properties, cyclodextrins can form inclusion complexes with a wide range of guest molecules. Although synthetic modifications of cyclodextrins through hydroxy groups are very common, modifications at backbone continue to be a challenge. Backbone modified cyclodextrins using different organic moieties were developed and their altered cavity properties were explored in many instances. Chemical synthesis of cyclic oligosaccharides is, in general, involved (i) a cyclo-oligomerization of linear oligosaccharide precursor and (ii) an one-pot polycondensation of appropriately designed monomer under suitable reaction conditions. The second part of Chapter 1 deals with a literature survey of skeletal modification of cyclodextrins, their synthesis and binding abilities with different guest molecules. In my research programme, synthesis and studies of oligosaccharide glycolipids relevant to mycobacterial cell wall were undertaken. Arabinofuranoside trisaccharide glycolipids, containing β-anomeric linkages at the non-reducing ends and double hexadecyloxy lipid moieties, interconnected to the sugar moiety through a glycerol core, were synthesized (Figure 1). Arabinan trisaccharides 1 with lipidic chain and 3 without lipidic chain comprise β-(1→2), β-(1→3) anomeric linkages at the non-reducing end, whereas in the case of arabinan trisaccharides 2 and 4, β-(1→2), β-(1→5) linkages are present between the furanoside units. In the scheme of synthesis of trisaccharide glycolipids, monosaccharide derivative and lipidic portions were individually prepared first and were assembled subsequently to secure the target glycolipids. Incorporation of β-arabinofuranoside linkages in trisaccharide arabinofuranosides 1-4 was achieved by low temperature activation of silyl group protected conformationally locked thioglycoside donor 5 (Figure 1), in the presence of N-iodosuccinimide (NIS) and silver trifluoromethanesulfonate (AgOTf). Figure 1. Molecular structures of trisaccharides 3, 4 and glycolipids 1, 2 with β-arabinofuranoside linkages at the non-reducing end and glycosyl donor 5. Following the synthesis, the efficacies of synthetic glycolipids to interact with surfactant protein A (SP-A) were assessed by using surface plasmon resonance (SPR) technique, from which association-dissociation rate constants and equilibrium binding constants were derived. SP-A, a lung innate immune system component, is known to bind with glycolipids present in the cell surface of a mycobacterial pathogen. From the analysis of SPR studies with glycolipids 1, 2 and SP-A, the association rate constants (ka) were found to be in the range of 0.3 to 0.85 M−1 s−1, whereas the dissociation rate constants (kd) were varied between 2.21 and 3.2×10−3 s−1. The equilibrium constants (Ka) values were in the range of 93 and 274 M−1. Trisaccharides 3 and 4, without lipidic chains, were also assessed for their efficacies to interact with SP-A. The association constants for 3 were found to be in the range of 2,470 to 9,430 M−1, whereas for the derivative 4, Ka values varied between 25,600 and 76,900 M−1. The association and equilibrium binding constants for 3 and 4 were found to be significantly higher when compared to glycolipids 1 and 2. In conjunction with our previous report, the present study shows that arabinofuranoside glycolipids, with β-anomeric linkages bind to SP-A with lesser extent as compared to α-anomers. Further, the studies of trisaccharides and glycolipids in mycobacterial growth and sliding motility assays were performed with model organism M. smegmatis and it was found that the synthetic compounds affected both growth and motility and the extent was lesser than that of α-anomeric glycosides and glycolipids. Chapter 2 of the thesis describes the details of synthesis, biophysical and biological studies of arabinan trisaccharide glycolipids, with β-anomeric linkages at the non-reducing end. Continuing the synthesis and studies of arabinan oligosaccharides, a linear arabinomannan pentasaccharide and heptasaccharide glycolipids 6 and 10, containing α-(1→2) and α-(1→3) linkages between core arabinofuranoside units, as well as, a branched arabinomannan pentasaccharide and heptasaccharide glycolipids 7 and 11, with α-(1→2) and α-(1→5) linkages between core arabinofuranoside units, were synthesized (Figures 2 and 3). Figure 2. Molecular structures of arabinomannan glycolipids 6 and 7 and the corresponding oligosaccharides 8 and 9. In addition to glycolipids, arabinomannan pentasaccharides without lipidic chain 8 and 9 and arabinomannan heptasaccharides without lipidic chain 12 and 13, were also synthesized. Synthesis was performed using trichloroacetimidate and thioglycosides as glycosyl donors. A block condensation methodology was adopted by which disaccharide donor and monosaccharide acceptor were chosen to assemble the pentasaccharide, by a two-fold glycosylation. Monosaccharide acceptors with and without lipidic chain were used in the glycosylations for the synthesis of glycolipids and pentasaccharides, respectively. Similarly, a trisaccharide thioglycoside donor and monosaccharide acceptors were chosen for the double glycosylation to synthesize heptasaccharides in the presence of NIS and AgOTf. Figure 3. Molecular structures of arabinomannan heptasaccharide glycolipids 10, 11 and corresponding heptasaccharides 12 and 13. Subsequent to synthesis, activities of pentasaccharide glycolipids were assayed on M. smegmatis bacterial growth, sliding motilities and also the effects on mycobacterial biofilms. Profound effects were observed with the synthetic compounds, to reduce the mycobacterial growth, sliding motilities and biofilm structures. Whereas reduction up to ~50% occurred on mycobacterial growth, as much as, 70% reduction in the motilities of the bacteria was observed in the presence of the synthetic glycolipids, at 100 µg mL-1 concentration. At the same concentration, 80–85% reduction in the biofilm was observed. These effects were more pronounced with branched glycolipids than linear analogues. Chapter 3 of the thesis presents the synthesis of linear and branched arabinomannan penta- and heptasaccharide glycolipids and biological studies of arabinomannan pentasaccharide glycolipids with M. smegmatis. Cyclodextrins, the most abundant naturally-occurring cyclic oligosaccharides, are valuable synthetic hosts, primarily as a result of their properties to form inclusion complexes with guest molecules. In spite of voluminous literature on the application of cyclodextrins, through modifications of hydroxy groups, modifications at the backbone continue to be a challenge. Skeletal modifications using aromatic, triazole, diyne, thioether and disulfide moieties were developed, that helped to alter the cavity properties of cyclodextrins. A programme was undertaken to synthesize backbone modified cyclic oligosaccharide, which was achieved using a monomer wherein a one carbon insertion is conducted at C4 of a pyranose, such that the hydroxy moiety at C4 is replaced with a hydroxymethyl moiety. In an approach, a linear trisaccharide monomer was anticipated to provide cyclic oligosaccharides in multiples of such a monomer. In the event, a trisaccharide linear monomer 14 was found to afford a cyclic trisaccharide macrocycle 15, as the major cyclo-oligomer (Scheme 1). Subsequent solid state structural studies show that the molecule confers a perfect trigonal symmetry in the P3 space group, in a narrow cone shape and a brick-wall type arrangement of molecules, such a geometry is hither-to unknown to a cyclic oligosaccharide (Figure 4). Furthermore, binding abilities of cyclic trisaccharide with few organic bases, such as 1-aminoadamantane and hexamethylenetetramine, was evaluated by the means of isothermal titration calorimetry and it was found that such a cyclic trisaccharide exhibits strong binding affinities towards 1-aminoadamantane in aqueous solutions, as compared to the same with naturally-occurring β-cyclodextrin. Scheme 1 Apart from cyclic trisaccharide, synthesis of cyclic tetrasaccharide 17, containing alternative anomeric α-(1→4) and β-(1→4) linkages was also undertaken by one-pot cyclo-oligomerization in the suitable reaction condition, from an activated disaccharide thioglycoside monomer 16, having β-(1→4) linkage at the non-reducing end (Scheme 2). Chapter 4 describes the synthesis of cyclic oligosaccharides 15 and 17, as well as, the details of solid state structure and binding studies of cyclic trisaccharide 15. Scheme 2 Figure 4. (a) Stick model of the crystal structure of 15, as viewed along the crystallographic c-axis; (b) trigonal view from crystal packing; (c) packing diagram crystal lattice, as viewed along the crystallographic b-axis, and without solvent inclusion and (d) packing diagram included with methanol (grey) and water (red) solvents, as viewed along the crystallographic c-axis. Hydrogen atoms are omitted for clarity in (c and d). In summary, the thesis presents (i) synthesis, biophysical and biological studies of synthetic arabinan and arabinomannan glycolipids, and (ii) synthesis, solid-state structural analysis and binding studies of glycosidic bond expanded cyclic oligosaccharides. Synthetic trisaccharide arabinofuranoside glycolipids containing β-anomeric linkages at the non-reducing end showed binding affinity towards pulmonary surfactant protein A, as assessed by surface plasmon resonance technique, with comparatively lower extent as compared to synthetic glycolipids having α-anomeric linkages. Linear and branched arabinomannan penta- and heptasaccharide glycolipids, having α-anomeric linkages were synthesized and biological studies with non-pathogenic strain M. smegmatis were conducted with pentasaccharide glycolipids. It was found that arabinomannan glycolipids inhibited the growth and sliding motility of mycobacteria. Importantly, disruption of biofilm and significant reduction in biofilm formation was observed in the presence of the synthetic glycolipids. Glycosidic bond expanded cyclic trisaccharide with anomeric α-(1→4) linkages and cyclic tetrasaccharide with alternative anomeric α-(1→4) and β-(1→4) linkages were prepared from suitably designed trisaccharide and disaccharide monomer, respectively, by cyclo-oligomerization. Solid-state structural analysis and binding studies of cyclic trisaccharide in solution by isothermal titration calorimetry were also conducted. Cyclic trisaccharide possessed a bowl shape and brick-wall type of arrangement in the solid-state structure, whereas it exhibited stronger binding affinity towards 1-aminoadamantane as compared to β-cyclodextrin in aqueous solution. Overall, the results presented in the thesis provide a possibility to develop new types of synthetic glycolipids that can act as inhibitors of biofilm formation of mycobacteria, as well as, to develop newer types of cyclic oligosaccharide synthetic hosts that can modify binding abilities towards various guest compounds.