Tabla de Contenidos: “…1 introduction 3 -- references 5 -- 2 intermediate filaments - from proteins to networks 9 -- 2.1 Structure and assembly of intermediate filament proteins 10 -- 2.2 Mechanical properties of single intermediate filaments 12 -- 2.2.1 Persistence length 12 -- 2.2.2 Stretching response . 13 -- 2.3 Networks of reconstituted intermediate filaments . 15 -- 2.4 Intermediate filament networks in cells . 16 -- 2.4.1 Structure and function of intermediate filament networks in cells 16 -- 2.4.2 Intermediate filament networks and cell mechanics 16 -- 2.4.3 Keratin networks in cells under load . 17 -- references 17 -- 3 biopolymer mechanics - theoretical and experimental principles 29 -- 3.1 Optical tweezers . 29 -- 3.1.1 Particle trapping 30 -- 3.1.2 Force detection . 31 -- 3.2 Microrheology 34 -- 3.2.1 Rheology of viscoelastic materials 34 -- 3.2.2 Passive microrheology: microparticle tracking . 34 -- 3.2.3 Active microrheology: optical trapping . 36 -- 3.3 Polymer mechanics . 38 -- 3.3.1 Entropic stretching of worm-like chains . 38 -- 3.3.2 Worm-like bundles . 39 -- 3.3.3 Networks of semiflexible polymers . 39 -- 3.4 Molecular reactions . 43 -- 3.4.1 Step-growth polymerization . 43 -- 3.4.2 Molecular reaction kinetics - two state models . 43 -- references 44 -- 4 materials and methods 51 -- 4.1 Vimentin preparation 51 -- 4.2 Maleimide functionalization of polystyrene beads . 52 -- 4.3 Stretching single filaments by optical trapping . 53 -- 4.4 Analysis of single filament mechanics 54 -- 4.5 Force-strain Monte-Carlo simulations 56 -- 4.6 Optical trap measurements of individual filament-filament interactions . 56 -- 4.7 Analysis of the interaction data 58 -- 4.8 Microrhelogy of reconstituted vimentin networks . 60 -- 4.9 Analysis of microrheology experiments . 61 -- 4.10 Imaging filament networks 63 -- 4.11 Imaging single filaments 63 -- 4.12 Analysis of filament lengths 64 -- 4.13 Finite element simulation of the microfluidic flowcell . 64 -- 4.14 Stretching MDCK II cells on elastic substrates . 65 -- 4.15 Analysis of images of stretched cells . 68 -- references 70 -- 5 tuning intermediate filament mechanics by variation of -- ph and ion charges 75 -- 5.1 Introduction . 76 -- 5.2 Results and discussion . 77 -- 5.2.1 Cations stiffen single vimentin IFs 77 -- 5.2.2 Stretching vimentin filament bundles 81 -- 5.2.3 IF mechanics adapt to pH changes 82 -- 5.2.4 IF stiffening saturates at low pH . 83 -- 5.2.5 Variations in the free energy landscapes influence filament mechanics 85 -- 5.3 Conclusions . 90 -- references 91 -- 6 multiscale mechanics and temporal evolution of vimentin -- intermediate filament networks 97 -- 6.1 Introduction . 98 -- 6.2 Results and discussion . 98 -- 6.2.1 Vimentin filament networks mature and stiffen on time scales of days 98 -- 6.2.2 The filament length depends on elongation and lateral association 100 -- 6.2.3 Electrostatic and hydrophobic interactions lead to mechanically distinct networks 101 -- 6.2.4 Maturation of networks is concentration dependent 104 -- 6.2.5 Surface effects modify network structures . 105 -- 6.2.6 Single filament mechanics are unaffected by detergents or divalent ions . 107 -- 6.2.7 Electrostatics increase single filament-filament interactions108 -- 6.2.8 Interactions are independent of binding-site encounter rate112 -- 6.2.9 A two-state model accurately describes network mechanics112 -- 6.3 Conclusions . 113 -- 6.4 Outlook 115 -- 6.4.1 Entropic and elastic stretching of single vimentin filaments115 -- 6.4.2 Single interactions of pre-strained filaments 117 -- references 119 -- 7 response of actin and keratin structures to isotropic cell stretching 125 -- 7.1 Introduction . 125 -- 7.2 Results and Discussion . 126 -- 7.2.1 Equibiaxial stretching of PDMS devices . 126 -- 7.2.2 The cell area increases during isotropic stretching . 128 -- 7.2.3 Actin stress fibers disassemble at increasing cell extension 129 -- 7.2.4 The keratin structure adapts to increasing strains . 131 -- 7.3 Conclusion 133 -- references 133 -- 8 discussion and conclusion 137 -- references 140 -- appendix 145 -- a supporting information: tuning intermediate filament mechanics by variation of ph and ion charges 145 -- a.1 Flow simulations 145 -- a.2 Single force-strain curves . 147 -- b supporting information: multiscale mechanics and temporal evolution of vimentin intermediate filament networks 149 -- b.1 Additional information for elongation measurements . 149 -- b.2 Data analysis of microrheology measurements . 152 -- b.3 Modeling single interactions 161 -- c supporting information: response of actin and keratin structures to isotropic cell stretching 167 -- references 169 -- Acknowledgments 172 -- List of acronyms 174 -- Publications 176.…”

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“…Se caracterizó la actividad de una nueva proteína supresora del PTGS, la proteína 15K codificada en el genoma del Garlic mite-borne filamentous virus (GmbFV). Si bien esta proteína muestra una actividad supresora débil en plantas silenciadas por agroinfiltración con transgenes u horquillas de silenciamiento, presenta la ventaja de no producir fenotipos aberrantes en plantas transgénicas. …”
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“…Preliminary evaluation of fungicidal activity of essential oils of eucalyptus (Eucalyptus tereticornis, Myrtaceae) and orange peel (Citrus sinensis, Rutaceae) on some filamentous fungi…”
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“…Preliminary evaluation of fungicidal activity of essential oils of eucalyptus (Eucalyptus tereticornis, Myrtaceae) and orange peel (Citrus sinensis, Rutaceae) on some filamentous fungi…”
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