An improvement and proof of OGY method

OGY method is the most important method of controlling chaos. It stabilizes a hyperbolic periodic orbit by making small perturbations for a system parameter. This paper improves the method of choosing parameter, and gives a mathematics proof of it.

A time domain computation method for dynamic behavior of mooring system

A quasi-steady time domain method is developed for the prediction of dynamic behavior of a mooring system under the environmental disturbances, such as regular or irregular waves, winds and currents. The mooring forces are obtained in a static sense at each instant. The dynamic feature of the mooring cables can be obtained by incorporating the extended 3-D lumped-mass method with the known ship motion history. Some nonlinear effects, such as the influence of the instantaneous change of the wetted hull surface on the hydrostatic restoring forces and Froude-Krylov forces, are included. The computational results show a satisfactory agreement with the experimental ones.

Numerical study of bifurcation solutions of spherical Taylor-Couette flow

The steady bifurcation flows in a spherical gap (gap ratio sigma=0.18) with rotating inner and stationary outer spheres are simulated numerically for Re(c1)less than or equal to Re less than or equal to 1 500 by solving steady axisymmetric incompressible Navier-Stokes equations using a finite difference method. The simulation shows that there exist two steady stable flows with 1 or 2 vortices per hemisphere for 775 less than or equal to Re less than or equal to 1 220 and three steady stable flows with 0, 1, or 2 vortices for 1 2201 500. The formation of different flows at the same Reynolds number is related with different initial conditions which on be generated by different accelerations of the inner sphere. Generation of zero-or two-vortex flow depends mainly on the acceleratio n, but that of one-vortex flow also depends on the perturbation breaking the equatorial symmetry. The mechanism of development of a saddle point in the meridional plane at higher Re number and its role in the formation of two-vortex flow are analyzed.

Preliminary-results of gaas single-crystal growth under high gravity conditions

GaAs single crystals have been grown under high gravity conditions, up to 9g0, by a recrystallization method with decreasing temperature. The impurity striations in GaAs grown under high gravity become weak and indistinct with smaller striation spacings. The dislocation density of surcharge-grown GaAs increases with increase of centrifugal force. The cathodoluminescence results also show worse perfection in the GaAs grown at high gravity than at normal earth gravity.

The motion and the core structure of a geostrophic vortex - one-time scale inner solution and the motion of the vortex

By means of the matched asymptotic expansion method with one-time scale analysis we have shown that the inviscid geostrophic vortex solution represents our leading solution away from the vortex. Near the vortex there is a viscous core structure, with the length scale O(a). In the core the viscous stresses (or turbulent stresses) are important, the variations of the velocity and the equivalent height are finite and dependent of time. It also has been shown that the leading inner solutions of the core structure are the same for two different time scales of S/(ghoo)1/2 and S/a (ghoo)1/2. Within the accuracy of O(a) the velocity of a geostrophic vortex center is equal to the velocity of the local background flow, where the vortex is located, in the absence of the vortex. Some numerical examples demonstrate the contributions of these results.

Measures of Plant Surface-areas for Eurasian Watermilfoil and Water Stargrass

Plant surface areas were measured from samples of two common submersed aquatics with widely diverging morphologies: Eurasian watermilfoil ( Myriophyllum spicatum L.) and water stargrass ( Heteranthera dubia (Jacq.) MacM.). Measures for the highly dissected leaves of Eurasian watermilfoil involved development of a regression equation relating leaf length to direct measures of a subsample of leaf parts. Measures for the simple leaves of the stargrass were sums of measured triangles. Stem surfaces for both species were calculated as measured cylinders. Though the means of the stem length and leaf length were larger for stargrass samples, their mean surface area was 95 cm 2 which was less than the 108 cm 2 recorded for Eurasian watermilfoil samples. Relating surface area to dry weight for the stargrass was straightforward, with 1 mg of dry weight yielding an average 0.678 cm 2 of surface area. Biomass measures for the water milfoil were confounded by the additional weight of epiphytic algae persisting on cleaned samples. The results suggest that a lesstime consuming method for surface area measures of plants with highly dissected leaves and a caveat for using biomass measures to estimate surface area in such plants.

Numerical Simulation of R-M Instability

In order to capture shock waves and contact discontinuities in the field and easy to program with parallel computation a new algorithm is developed to solve the N-S equations for simulation of R-M instability problems. The method with group velocity control is used to suppress numerical oscillations, and an adaptive non-uniform mesh is used to get fine resolution. Numerical results for cylindrical shock-cylindrical interface interaction with a shock Mach number Ms=1.2 and Atwood number A=0.818, 0.961, 0.980 (the interior density of the interface/outer density p(1)/p(2) = 10, 50, 100, respectively), and for the planar shock-spherical interface interaction with Ms=1.2 and p(1)/p(2) = 14.28are presented. The effect of Atwood number and multi-mode initial perturbation on the R-M instability are studied. Multi-collisions of the reflected shock with the interface is a main reason of nonlinear development of the interface instability and formation of the spike-bubble structures In simulation with double mode perturbation vortex merging and second instability are found. After second instability the small vortex structures near the interface produced. It is important factor for turbulent mixing.

Scientific Data Application Profile Scoping Study

This study was undertaken by UKOLN on behalf of the Joint Information Systems Committee (JISC) in the period April to September 2008. Application profiles are metadata schemata which consist of data elements drawn from one or more namespaces, optimized for a particular local application. They offer a way for particular communities to base the interoperability specifications they create and use for their digital material on established open standards. This offers the potential for digital materials to be accessed, used and curated effectively both within and beyond the communities in which they were created. The JISC recognized the need to undertake a scoping study to investigate metadata application profile requirements for scientific data in relation to digital repositories, and specifically concerning descriptive metadata to support resource discovery and other functions such as preservation. This followed on from the development of the Scholarly Works Application Profile (SWAP) undertaken within the JISC Digital Repositories Programme and led by Andy Powell (Eduserv Foundation) and Julie Allinson (RRT UKOLN) on behalf of the JISC. Aims and Objectives 1.To assess whether a single metadata AP for research data, or a small number thereof, would improve resource discovery or discovery-to-delivery in any useful or significant way. 2.If so, then to:a.assess whether the development of such AP(s) is practical and if so, how much effort it would take; b.scope a community uptake strategy that is likely to be successful, identifying the main barriers and key stakeholders. 3.Otherwise, to investigate how best to improve cross-discipline, cross-community discovery-to-delivery for research data, and make recommendations to the JISC and others as appropriate. Approach The Study used a broad conception of what constitutes scientific data, namely data gathered, collated, structured and analysed using a recognizably scientific method, with a bias towards quantitative methods. The approach taken was to map out the landscape of existing data centres, repositories and associated projects, and conduct a survey of the discovery-to-delivery metadata they use or have defined, alongside any insights they have gained from working with this metadata. This was followed up by a series of unstructured interviews, discussing use cases for a Scientific Data Application Profile, and how widely a single profile might be applied. On the latter point, matters of granularity, the experimental/measurement contrast, the quantitative/qualitative contrast, the raw/derived data contrast, and the homogeneous/heterogeneous data collection contrast were discussed. The Study report was loosely structured according to the Singapore Framework for Dublin Core Application Profiles, and in turn considered: the possible use cases for a Scientific Data Application Profile; existing domain models that could either be used or adapted for use within such a profile; and a comparison existing metadata profiles and standards to identify candidate elements for inclusion in the description set profile for scientific data. The report also considered how the application profile might be implemented, its relationship to other application profiles, the alternatives to constructing a Scientific Data Application Profile, the development effort required, and what could be done to encourage uptake in the community. The conclusions of the Study were validated through a reference group of stakeholders.

Fangtechnische Möglichkeiten zur Reduzierung des Beifangs von Meeresenten in der Dorschfischerei mit stationären Fanggeräten

The present contribution summarizes results of fishery investigations with gillnets and longlines in the winter cod fishery which had been carried out in the western Baltic region from 1996 to 1999 by the Bundesforschungsanstalt für Fischerei with financial aid of the country Schleswig-Holstein. The main goal of these investigations was to point out technological possibilities for a reduction of unwanted bycatches of sea ducks in gillnetting. As it is obviously impossible to reduce the local and temporal bycatch problem by means of different gillnet constructions or tactical measurements, only the temporary avoidance of fishing grounds with high abundance of ducks or the change to longlining as catch method with reduced duck bycatches may be an effective solution.

I. Exact solution of some nonlinear evolution equations. II. The similarity solution for the Korteweg-De Vries equation and the related Painleve Transcendent

In Part I, a method for finding solutions of certain diffusive dispersive nonlinear evolution equations is introduced. The method consists of a straightforward iteration procedure, applied to the equation as it stands (in most cases), which can be carried out to all terms, followed by a summation of the resulting infinite series, sometimes directly and other times in terms of traces of inverses of operators in an appropriate space.

We first illustrate our method with Burgers' and Thomas' equations, and show how it quickly leads to the Cole-Hopft transformation, which is known to linearize these equations.

We also apply this method to the Korteweg and de Vries, nonlinear (cubic) Schrödinger, Sine-Gordon, modified KdV and Boussinesq equations. In all these cases the multisoliton solutions are easily obtained and new expressions for some of them follow. More generally we show that the Marcenko integral equations, together with the inverse problem that originates them, follow naturally from our expressions.

Only solutions that are small in some sense (i.e., they tend to zero as the independent variable goes to ∞) are covered by our methods. However, by the study of the effect of writing the initial iterate u_1 = u_(1)(x,t) as a sum u_1 = ^∼/u_1 + ^≈/u_1 when we know the solution which results if u_1 = ^∼/u_1, we are led to expressions that describe the interaction of two arbitrary solutions, only one of which is small. This should not be confused with Backlund transformations and is more in the direction of performing the inverse scattering over an arbitrary “base” solution. Thus we are able to write expressions for the interaction of a cnoidal wave with a multisoliton in the case of the KdV equation; these expressions are somewhat different from the ones obtained by Wahlquist (1976). Similarly, we find multi-dark-pulse solutions and solutions describing the interaction of envelope-solitons with a uniform wave train in the case of the Schrodinger equation.

Other equations tractable by our method are presented. These include the following equations: Self-induced transparency, reduced Maxwell-Bloch, and a two-dimensional nonlinear Schrodinger. Higher order and matrix-valued equations with nonscalar dispersion functions are also presented.

In Part II, the second Painleve transcendent is treated in conjunction with the similarity solutions of the Korteweg-de Vries equat ion and the modified Korteweg-de Vries equation.

Three-dimensional models of mantle convection : influence of phase transitions and temperature-dependent viscosity

Two of the most important questions in mantle dynamics are investigated in three separate studies: the influence of phase transitions (studies 1 and 2), and the influence of temperature-dependent viscosity (study 3).

(1) Numerical modeling of mantle convection in a three-dimensional spherical shell incorporating the two major mantle phase transitions reveals an inherently three-dimensional flow pattern characterized by accumulation of cold downwellings above the 670 km discontinuity, and cylindrical 'avalanches' of upper mantle material into the lower mantle. The exothermic phase transition at 400 km depth reduces the degree of layering. A region of strongly-depressed temperature occurs at the base of the mantle. The temperature field is strongly modulated by this partial layering, both locally and in globally-averaged diagnostics. Flow penetration is strongly wavelength-dependent, with easy penetration at long wavelengths but strong inhibition at short wavelengths. The amplitude of the geoid is not significantly affected.

(2) Using a simple criterion for the deflection of an upwelling or downwelling by an endothermic phase transition, the scaling of the critical phase buoyancy parameter with the important lengthscales is obtained. The derived trends match those observed in numerical simulations, i.e., deflection is enhanced by (a) shorter wavelengths, (b) narrower up/downwellings (c) internal heating and (d) narrower phase loops.

(3) A systematic investigation into the effects of temperature-dependent viscosity on mantle convection has been performed in three-dimensional Cartesian geometry, with a factor of 1000-2500 viscosity variation, and Rayleigh numbers of 10^5-10^7. Enormous differences in model behavior are found, depending on the details of rheology, heating mode, compressibility and boundary conditions. Stress-free boundaries, compressibility, and temperature-dependent viscosity all favor long-wavelength flows, even in internally heated cases. However, small cells are obtained with some parameter combinations. Downwelling plumes and upwelling sheets are possible when viscosity is dependent solely on temperature. Viscous dissipation becomes important with temperature-dependent viscosity.

The sensitivity of mantle flow and structure to these various complexities illustrates the importance of performing mantle convection calculations with rheological and thermodynamic properties matching as closely as possible those of the Earth.

Reactivity of titanocene methylidene with metal halides, alkene sulfides, and alkene oxides

Titanocene metallacyclobutanes show a wide variety of reactivites with organic and inorganic reagents. Their reactions include methylene transfer to organic carbonyls, formation of enolates, electron transfer from activated alkyl chlorides, olefin metathesis, ring opening polymerization. Recently, preparations of heterobinuclear µ-methylene complexes were reported. In this thesis, mechanistic, synthetic, and structural studies of the heterobinuclear µ-methylene complexes will be described. Also, the reaction of titanocene methylidene trimethylphosphine complex with alkene sulfide and styrene sulfide will be presented.

Heterobinuclear µ-methylene-µ-methyl complexes C_(p2)Ti(µ-CH_2)( µ-CH_3)M(1,5-COD) have been prepared (M = Rh, Ir). X-ray crystallography showed that the methyl group of the complex was bonded to the rhodium and bridges to the titanium through an agostic bond. The ^(1)H,^(13)CNMR, IR spectra along with partial deuteration studies supported the structure in both solution and solid state. Activation of the agostic bond is demonstrated by the equilibration of the µ-CH_3 and µ-CH_2 groups. A nonlinear Arrhenius plot, an unusually large kinetic isotope effect (24(5)), and a large negative activation entropy (-64(3)eu) can be explained by the quantum-mechanical tunneling. Calculated rate constants with Bell-type barrier fitted well with the observed one. This equilibration was best explained by a 4e-4c mechanism (or σ bond metathesis) with the character of quantum-mechanical tunneling.

Heterobinuclear µ-methylene-µ-phenyl complexes were synthesized. Structural study of C_(p2)Ti(µ-CH_(2))(µ-p-Me_(2)NC_(6)H_(4))Rh(l,5-COD) showed that the two metal atoms are bridged by the methylene carbon and the ipso carbon of the p-N,N-dimethylarninophenyl group. The analogous structure of C_(p2))Ti(µ-CH_(2))(µ-o-MeOC_(6)H_(4))Rh(1,5-COD) has been verified by the differential NOE. The aromaticity of the phenyl group observed by ^(1)H NMR, was confirmed by the comparison of the C-C bond lengths in the crystallographic structure. The unusual downfield shifts of the ipso carbon in the ^(13)C NMR are assumed to be an indication of the interaction between the ipso carbon and electron-deficient titanium.

Titanium-platinum heterobinuclear µ-methylene complexes C_(p2)Ti(µ-CH_(2))(µ -X)Pt(Me)(PM_(2)Ph) have been prepared (X= Cl, Me). Structural studies indicate the following:(1) the Ti-CH2 bond possesses residual double bond character, (2) there is a dative Pt→Ti interaction which may be regarded as a π back donation from the platinum atom to the 'Ti=CH_(2)'' group, and (3) the µ-CH_3 group is bound to the titanium atom through a three-center, two-electron agostic bond.

Titanocene (η^(2)-thioformaldehyde)•PMe_3 was prepared from C_(p2)Ti=CH_(2)•PMe_3 and sulfur-containing organic compounds (e.g. alkene sulfide, triphenylphosphine sulfide) including elemental sulfur. Mechanistic studies utilizing trans-styrene sulfide-d_1 suggested the stepwise reaction to explain equimolar mixture of trans- and cis-styrene-d_1 as by-products. The product reacted with methyl iodide to produce cationic titanocene (η_(2)-thiomethoxymethyl) complex. Complexes having less coordinating anion like BF_4 or BPh_4 could be obtained through metathesis. Together with structural analyses, the further reactivities of the complexes have been explored.

The complex C_(p2)TiOCH_(2)CH(Ph)CH_2 was prepared from the compound C_(p2)Ti=CH_(2)-PMe_3 and styrene oxide. The product was characterized with ^(1)H-^(1)H correlated 2-dimensional NMR, selective decoupling of ^(1)H NMR, and differential NOE. Stereospecificity of deuterium in the product was lost when trans-styrene oxide-d_1 was allowed to react. Relative rates of the reaction were measured with varying substituents on the phenyl ring. Better linearity (r = -0.98, p^(+) = -0.79) was observed with σ_(p)^(+)than σ(r = -0.87, p = -1.26). The small magnitude of p^+ value and stereospecificity loss during the formation of product were best explained by the generation of biradicals, but partial generation of charge cannot be excluded. Carbonylation of the product followed by exposure to iodine yields the corresponding β-phenyl γ-lactone.

Studies of phonon anharmonicity in solids

Today our understanding of the vibrational thermodynamics of materials at low temperatures is emerging nicely, based on the harmonic model in which phonons are independent. At high temperatures, however, this understanding must accommodate how phonons interact with other phonons or with other excitations. We shall see that the phonon-phonon interactions give rise to interesting coupling problems, and essentially modify the equilibrium and non-equilibrium properties of materials, e.g., thermodynamic stability, heat capacity, optical properties and thermal transport of materials. Despite its great importance, to date the anharmonic lattice dynamics is poorly understood and most studies on lattice dynamics still rely on the harmonic or quasiharmonic models. There have been very few studies on the pure phonon anharmonicity and phonon-phonon interactions. The work presented in this thesis is devoted to the development of experimental and computational methods on this subject.

Modern inelastic scattering techniques with neutrons or photons are ideal for sorting out the anharmonic contribution. Analysis of the experimental data can generate vibrational spectra of the materials, i.e., their phonon densities of states or phonon dispersion relations. We obtained high quality data from laser Raman spectrometer, Fourier transform infrared spectrometer and inelastic neutron spectrometer. With accurate phonon spectra data, we obtained the energy shifts and lifetime broadenings of the interacting phonons, and the vibrational entropies of different materials. The understanding of them then relies on the development of the fundamental theories and the computational methods.

We developed an efficient post-processor for analyzing the anharmonic vibrations from the molecular dynamics (MD) calculations. Currently, most first principles methods are not capable of dealing with strong anharmonicity, because the interactions of phonons are ignored at finite temperatures. Our method adopts the Fourier transformed velocity autocorrelation method to handle the big data of time-dependent atomic velocities from MD calculations, and efficiently reconstructs the phonon DOS and phonon dispersion relations. Our calculations can reproduce the phonon frequency shifts and lifetime broadenings very well at various temperatures.

To understand non-harmonic interactions in a microscopic way, we have developed a numerical fitting method to analyze the decay channels of phonon-phonon interactions. Based on the quantum perturbation theory of many-body interactions, this method is used to calculate the three-phonon and four-phonon kinematics subject to the conservation of energy and momentum, taking into account the weight of phonon couplings. We can assess the strengths of phonon-phonon interactions of different channels and anharmonic orders with the calculated two-phonon DOS. This method, with high computational efficiency, is a promising direction to advance our understandings of non-harmonic lattice dynamics and thermal transport properties.

These experimental techniques and theoretical methods have been successfully performed in the study of anharmonic behaviors of metal oxides, including rutile and cuprite stuctures, and will be discussed in detail in Chapters 4 to 6. For example, for rutile titanium dioxide (TiO₂), we found that the anomalous anharmonic behavior of the B_1g mode can be explained by the volume effects on quasiharmonic force constants, and by the explicit cubic and quartic anharmonicity. For rutile tin dioxide (SnO₂), the broadening of the B_2g mode with temperature showed an unusual concave downwards curvature. This curvature was caused by a change with temperature in the number of down-conversion decay channels, originating with the wide band gap in the phonon dispersions. For silver oxide (Ag₂O), strong anharmonic effects were found for both phonons and for the negative thermal expansion.

Composição florística e estrutura da comunidade arbustivo-arbórea de um trecho de floresta submontana na vertente sudeste do Parque Estadual da Ilha Grande, Angra dos Reis / RJ

O estudo objetivou avaliar a composição florística e estrutural dos componentes arbustivo-arbóreo da Floresta Ombrófila Densa submontana em diferentes estágios de regeneração natural, na vertente sudeste do Parque Estadual da Ilha Grande/RJ. Para o inventário florístico foram realizadas coletas assistemáticas em diferentes trechos nessa vertente. A complementação da lista de espécies foi feita a partir, da consulta às exsicatas dos herbários do Rio de Janeiro (FCAB, GUA, HB, HRJ, R, RB, RBR, RFA, RFFP e RUSU) e do inventário fitossociológico. Foi verificado o status de conservação das espécies inventariadas para a Flora Brasileira. Para o inventário fitossociológico foram estabelecidas 34 parcelas amostrais, totalizando 1,02 ha de área amostrada. Todos os indivíduos arbustivo-arbóreos com DAP ≥ 5 cm foram registrados e, após identificação, foram depositados no Herbário da Universidade do Estado do Rio de Janeiro (HRJ). O pacote estatístico FITOPAC 2.1. foi utilizado para a análise dos dados. A similaridade entre o remanescente investigado neste estudo e as outras quatorze áreas distintas do Rio de Janeiro, da própria Ilha Grande ou não, foi avaliada, utilizando-se o coeficiente de Similaridade de Sorensen; pelo critério de agrupamento por ligação média não ponderada (UPGMA) e pelo método de autorreamostragem para a estrutura de grupos; utilizados os programas PAST v1.34 e Multiv 2.4. A partir do levantamento em herbários e dos inventários florístico e fitossociológico realizados neste trabalho, foram analisados 3.470 registros, sendo 1.778 do levantamento de herbários, 1.536 do levantamento fitossociológico e 156 do inventário florístico. Esses registros corresponderam a 606 espécies ou morfo-espécies de Angiospermas e uma de Pteridófita. Os resultados obtidos revelaram a existência de 22 espécies ameaçadas de extinção para a Flora do Brasil. Dentre, as quais, sete são exclusivas da amostragem fitossociológica: Abarema cochliacarpos (Gomes) Barneby & J.W. Grimes, Chrysophyllum flexuosum Mart., Ficus pulchella Schott ex Spreng., Macrotorus utriculatus Perkins, Myrceugenia myrcioides (Cambess.) O.Berg, Rudgea interrupta Benth e Urbanodendron bahiense (Meisn.) Rohwer. No estudo fitossociológico, inventariou-se 1.536 indivíduos de 217 espécies, subordinadas a 53 famílias. O índice de diversidade de Shannon (H) calculado foi de 4,702 nats/ind e equabilidade (J) de 0,874. As 10 famílias com maior riqueza foram: Myrtaceae (31 spp.), Rubiaceae (21), Fabaceae (17), Lauraceae (12), Euphorbiaceae (11), Monimiaceae (8), Melastomataceae (7), Sapindaceae (7), Sapotaceae (6) e Annonaceae (6). Os 10 maiores Valores de Importância das espécies foram para Chrysophyllum flexuosum (3,43%), Lamanonia ternata Vell. (3,40%), Hyeronima alchorneoides Allemão (2,83%), Actinostemon verticillatus (Klotzsch) Baill. (2,55%), Psychotria brasiliensis Vell. (2,55%), Eriotheca pentaphylla (Vell.) A. Robyns (2,28%), Guatteria australis A. St.-Hil. (2,12%), Mabea brasiliensis Müll. Arg. (2,04%), Miconia prasina (Sw.) DC. (1,89%) e Rustia formosa (Cham. & Schltdl. ex DC.) Klotzsch (1,82%). Amostraram-se 27% de espécies representadas por apenas um indivíduo. As análises florísticas avaliadas a partir do Índice de Similaridade de Sorensen indicaram como principais variáveis para a formação dos blocos, os diferentes valores de diversidade para as áreas e a distribuição fitogeográfica das espécies. Os resultados obtidos junto aos dados dos grupos ecológicos, para os indivíduos da fitossociologia, indicaram maior percentual de indivíduos secundários tardios amostrados. Conclui-se que a área de estudo é uma floresta secundária em estágio intermediário de regeneração, com grande riqueza de espécies, muitas das quais de relevante importância ecológica.

Produção in vitro e criopreservação de raízes de Cleome rosea Vahl (Capparaceae)

Cleome rosea é uma espécie nativa, de porte herbáceo, ocorrente em restingas brasileiras. Estudos recentes têm revelado o potencial medicinal da espécie para importantes propriedades farmacológicas, como por exemplo, as atividades anti-inflamatória, antigenotóxica, antiviral e antibacteriana. Porém, nos últimos anos, C. rosea não tem sido encontrada em várias regiões de seu ambiente natural, devido, principalmente, às ações antrópicas. Dessa forma, torna-se relevante o desenvolvimento de métodos de conservação que permitam o estudo e exploração das propriedades medicinais da espécie. O cultivo in vitro de raízes representa uma forma eficiente para produção de biomassa, devido ao rápido crescimento, produção estável de metabólitos, além de representar uma potencial fonte de explantes para a propagação em massa de diferentes espécies. O presente trabalho teve como objetivo a produção in vitro de culturas de raízes de C. rosea, associada à criopreservação, como forma de manutenção em longo prazo das culturas, monitorada através da análise de estabilidade genética. As culturas estabelecidas a partir de explantes radiculares de plantas propagadas in vitro de C. rosea demonstraram excelente capacidade de multiplicação de raízes em meio de cultura suplementado com o fitorregulador ANA, com manutenção dessa capacidade ao longo de sucessivas subculturas. Associado a esses resultados, o estabelecimento de protocolos de criopreservação pelo método de vitrificação resultou em elevados valores de frequência de recuperação do material após congelamento em nitrogênio líquido com as soluções de vitrificação PVS2 e PVS3. Os estudos de monitoramento da estabilidade genética, pela técnica de marcadores moleculares RAPD, revelaram a presença de polimorfismos significativos em uma das três culturas iniciadas a partir de raízes de C. rosea criopreservadas. Esses resultados demonstram as possibilidades de produção de raízes de C. rosea e conservação em longo prazo através da criopreservação, iniciando estudos inéditos para a espécie.