Although the impacts of foreign species on aqueous transformations and arsenic adsorption by 2-line ferrihydrite (FH2) have been extensively studied, much less is known about the impact of transformation inhibitors on solid-state transformation of FH2 and arsenic adsorption. In this study, the influence of inhibitors (Si(IV), Mg(II), Al(III), Ti(IV), and Ci(citrate)), aging time, and heat treatment on FH2 transformation and arsenic adsorption was investigated. The FH2s were synthesized by mixing Fe(III) salts with an inhibitor at pH 7.5 and air drying for 2 d. With increases in Al/Fe molar ratio, FH2, poorly crystalline Al hydroxide, gibbsite, and bayerite were formed in the FH2-Al series, whereas FH2 was formed in the other FH2s. Heat treatment had a more considerable impact on the transformation, structure, and PZC of FH2 than aging at RT for 235 d. Upon heating the FH2s at 360 oC, most of the amorphous Fe oxide was transformed into hematite, whereas Si and Al had stronger retarding effects on transformation than the other inhibitors. Hematite and FH2 were identified with increases in Si/Fe molar ratio, whereas with increasing Al/Fe molar ratio, FH2 remained, gibbsite and bayerite were decomposed, and boehmite appeared as a trace component. However, the effect of Si was much more pronounced than that of Al in retarding the transformation. The adsorption density for As(III) on the FH2s (at pH 7) decreased in the order: FH2-Mg-2 > FH2 > FH2-Al-1, whereas As(V) followed the order: FH2-Al-1 > FH2-Mg-2 > FH2. Compared to aging at RT for 235 d, heat treatment at 360 oC resulted in significantly reduced arsenic adsorption. The heated FH2 showed a smaller adsorption capacity for arsenic compare to that of the other FH2s. In contrast, the heated FH2-Al and FH2-Si series showed much higher adsorption capacities for As(V) than any other FH2, whereas the heated FH2-Mg series exhibited the largest adsorption capacity of As(III) among the heated FH2s. It is concluded that the use of the FH2-Al, FH2-Mg, or FH2-Si series instead of pure FH2 as filter media in water treatment might achieve more efficient arsenic removal and enhance arsenic retention at waste-disposal sites.

Marek's disease virus (MDV), the etiologic agent of Marek's disease, is a potent oncogenic herpesvirus. MDV is highly contagious and elicits a rapid onset of malignant T-cell lymphomas in chickens within several weeks after infection. The MDV genome encodes an oncoprotein, Meq, which shares resemblance with the Jun/Fos family of bZIP transcription factors. Similar to c-Jun, the leucine zipper region of Meq allows the formation of homo- and heterodimers. Meq homo- and heterodimers have different DNA binding affinities and transcriptional activity; therefore, they may differentially regulate transcription of viral and cellular genes. Previous in vitro data has suggested that Meq homodimers may be involved in regulating viral latency/reactivation, while Meq/c-Jun heterodimers are involved in transformation. Therefore, this research investigates the role of Meq homodimers and Meq-Jun heterodimers in the pathogenicity of MDV, by generating chimeric meq genes, which contain the leucine zipper region of the yeast transcription factor GCN4 (meqGCN) or leucine zipper region of c-Fos (meqFos). Thus producing Meq proteins that exclusively homodimerize (MeqGCN) or heterodimerize with Jun family members (MeqFos). Recombinant viruses (rMd5-MeqGCN and rMd5- MeqFos) containing the chimeric genes meqGCN or meqFos, respectively, in place of parental meq were generated with overlapping cosmid clones of Md5, a very virulent MDV strain. The chimeric genes were evaluated in vitro and retained DNA binding and transactivation/repressive functions, however, selected cells expressing MeqGCN and MeqFos had reduced colony formation in soft agar. Both the rMd5-MeqGCN and rMd5- MeqFos viruses replicated in vitro and in vivo, but rMd5-MeqGCN was unable to transform T-cells in infected chickens, while rMd5-MeqFos induced preneoplastic nerve lesions in 50% of infected birds. However, a third virus rMd5-MeqFos/GCN, which contains one copy of each meqGCN and meqFos, induced preneoplastic nerve lesions in 60% of infected chickens and neoplastic lesions in 20% of infected chickens. These data provide the first in vivo evidence that both Meq homodimers and heterodimers are necessary for MDV induced transformation.

Abstract This research is focused on the condensation and phase transformation of NiO-TiO2, Co1-XO-NiO, and Co1-XO-MgO solid solution via dynamic laser ablation condensation and high temperature annealing. TiO2 rutile nanospheres with enhanced solid solution of NiO were synthesized via very energetic pulse laser ablation on clamped Ni/Ti target in oxygen for a very rapid heating/cooling, and hence pressure effect. Upon electron irradiation, the NiO-dissolved rutile (r) were partially transformed into 2(01 ) commensurate superstructure and Ni2(1+x)Ti1-xO4 spinel (s) following the crystallographic relationship [111]r//[012]s; (10 )r//(200)s. Alternatively, random NiTiO3 nanodomains were formed from amorphous regions in such a rapid decomposition process. In addition, the dense fluorite-type (f) derived TiO2 condensates dissolved up to 5 at% Ni2+ of the cations were synthesized via the same route. The nanocondensates less than 20 nm in size are nearly cubo-octahedral in shape and tended to transform martensitically to monoclinic (m) baddeleyite-type following the crystallographic relationship (100)f//(110)m; [001]f//[001]m. The condensates twice larger in size, with considerable matrix constraint, are nearly spherical in shape and consist of mosaic m-twin variants following complicated crystallographic relationships with each other and with the relic f-phase: (010)f//( 20)m; [001]f//[001]m. The charge and volume compensating oxygen vacancies due to NiO dissolution in the dense TiO2 condensates could facilitate the relaxation and amorphization process. Further more, pulse laser irradiation of Ni, Co, and Co-Ni (or Ni-Co) targets in an oxygen background gas produced nanocondensates with rock-salt type structure. Analytical electron microscopic observations indicated that such nanocrystals are cubic in shape for NiO and cubo-octahedral for Co1-xO and Ni1-xCoxO. The nanocrystals coalesced predominantly with {100} or {111} facets to form nano chain aggregates or closer packed manner. The Co1-xO was more or less oxidized as Co3-

The diffusional transformation kinetics of C-Mn steels during continuous cooling have been measured and predicted in this study for predicting the non-isothermal multi-stage cooling transformation kinetics. A suitable thermodynamic model is assessed for determining the driving force of austenite to ferrite transformation and the austenite/ferrite interface concentrations under various equilibrium constraints, which are essential to determine the diffusion-controlled transformation kinetics. The continuous cooling transformation (CCT) curves of C-Mn steels are determined using dilatometric method. Pham¡¦s empirical growth model is found most suitable for describing the start and finish transformation curve. The Avrami equation, common-used for isothermal transformation, is found to be applicable to the continuous cooling transformation. The Avrami exponents, nF and nP, for ferrite- and pearlite- dominant CCT, respectively, are close to the isothermal ones reported in the literature. The Avrami constant, b, increases with decreasing austenitizing temperature, indicating a fast progress of transformation. Combining Pham¡¦s empirical growth model with Avrami equation, the CCT kinetics of C-Mn steels can be predicated well. The examination on the microstructural evolution during CCT suggests that the transformation of austenite to grain boundary allotriomorphs of ferrite (GBAF) can be divided into (1) nucleation and growth (NG) stage, (2) growth only (site saturation, SS) stage, and (3) coalescence stage. In the NG stage, the oblate ellipsoid aspect ratio of GBAF remains 3:1 until all the nucleation sites are exhausted., i.e. the onset of SS stage, then gradually decreases in the SS stage. Once the aspect ratio approaches unity, the coalescence starts to operate. Based on this observation, a physical base model is developed for predicting the austenite to GBAF CCT. This model possesses the capability to predict the start and finish transformation temperatures, the fraction transformed, and the final ferrite grain size. Although such model failed to predict the whole range of CCT curve due to the fact that only the GBAF transformation is included at present stage, it is still highly recommended for microstructural control. In order to completely predict the whole CCT curves, a semi-empirical physical base model is adopted. In addition, the methodology to predict multi-stage cooling transformation from CCT curves is also derived based on additivity rule and the concept of ideal TTT diagram. Associated with the additivity rule and the concept of ideal TTT diagram, such empirical model is validated to be applicable for the prediction of CCT and step wise cooling transformation. The latent heat is calculated using thermodynamic software for the accurate control of cooling history of the medium carbon steels which usually releases an abundance of latent heat. Associated with the semi-empirical transformation model, the calculation of latent heat is integrated into a heat transfer model and successfully implemented in a mill operation.

NPR (Non-Photorealistic Rendering) is a new and quick-developed research topic in Image Processing. The main purpose of NPR is to generate sketching or comics, something different from photos, automatically by computer algorithms. Examples of such applications include pen-and-ink tree or watercolor. On the other hands, there is another technique called PR (Photorealistic Rendering). The goal of PR is to generate real objects by computer algorithms. The performance of a PR program depends on the realities of the objects generated by the PR program. Furthermore, NPR includes two modes: one is with Physical Model and the other is not. 1.¡@With Physical Model: Researchers could write programs to simulate NPR by the properties of Physical Model. 2.¡@Without Physical Model: Researchers could write programs to simulate NPR by their observations and deliberation. Our research belongs to the second one, NPR without Physical Model. In the efforts of artists, some common consensuses about human facial proportion are brought up gradually. Then, the common standards are produced. In our research, there are several steps. First, read an input human front photo and separate main features from face, include the maximal and minimal values of left and right eyebrows, left and right eyes, left and right ears, nose and mouth, in horizontal and vertical. Then quantify these facial features. Next, we would construct a standard model based on the facial feature standard in arts. Compare the values we obtain from input human front photo with the values in the standard model, then we could obtain a cartoon face model. At last, adjust and exaggerate features according to scale relations between features of input face front photo and standard model and the distance among facial features. Keys of facial features transformation in this step are enlarging, shrinking, closing and separating. In varied parts, like face form and hair form, we hope to extract some sample feature points and use Bezier Curve in Numerical Analysis to draw them. That is because that lines of cartoon, unlike real human face, are sketched very smoothly and colors are uniform in general. We also provide several roles, one four grids comic and one cartoon animation. Users could import results of programs to those test images or image sequence, then complete these comics or cartoons based on input human face front photos. By this research, we hope that we could reach the goal that makes everyone as a main character of comics or cartoons.

This thesis is devoted to generating the boundary of face profile for face transformation in face combining, face resembling and face recognition. The face reformation can be carried by the geometric, harmonic model and numerical methods, such as the splitting shooting method(SSM) and the splitting integrating methods(SIM) of image transformation. However, the harmonic model needs the boundary correspondence in the Dirichlet condition. It is forbidding to depict the pixel-pixel correspondence, but is necessary to find a few important, charactistic point-point correspondences. Hence, we may seek the blending curves to establish the curve-curve correspondence. In this thesis, the formulation for the face boundary and profiles are explored by three methods: cubic spline, quadratic, spline, and the ordinary differential equation(ODE) approaches using Hermite interpolation. The latter is advantageous for handling different boundary conditions in 2D clamped, simply support conditions and given curvature. The combined algorithms using both cubic splines and the ODE methods are also developed. New mathematical algorithms of curves for given curvature on the boundary are proposed in this thesis, and the number of nonlinear equations involved in curvature conditions can be reduced to two or three only. This thesis also displays the validity of the ODE approaches for 2D curves. Graphical experiments are carried out to resembling face images of a young girl, based on the photos of her parents and her childhood.

Medicago truncatula (M. truncatula) has been proposed as a model legume for molecular and genetic studies of legumes. While many genetic resources have been developed for this model legume, genetic transformation of the M. truncatula line A17 proved to be a problem. A reproducible transformation method is described for M. truncatula A17. Procedures are detailed that yielded an average regeneration frequency of 35% for recovery of transgenic shoots from cotyledonary node explants. Previously, rooting of transgenic shoots of this line has proven difficult, but media and culture procedures are described that yielded an average frequency of 39% for root induction from 419 phosphinothricin-resistant shoots. Fertile M. truncatula A17 plants transgenic for 35S-GFP, phas-GUS or phas-GFP were obtained. The presence of transgenes was confirmed by expression of transgenes and by genomic DNA blots. Interestingly, although GUS and GFP driven by the phas promoter were very strongly and uniformly expressed in seed cotyledons of most transgenic M. truncatula lines, silencing of the GUS expression from the phas promoter was observed in several lines, indicating the occurrence of novel epigenetic events. The diminution of GFP fluorescence in transgenic M. truncatula occurs despite the presence of GFP transcript and protein. To evaluate the generality and causes of this phenomenon, fluorescence during leaf development from the same 35S-GFP transgene was compared in M. truncatula, rice and Arabidopsis. A substantial decrease in fluorescence early in the development of M. truncatula and rice leaves was found to correlate with chlorophyll accumulation. Several approaches showed that chlorophyll is causally involved in the loss of GFP fluorescence. Removal of chlorophyll from leaves of transgenic M. truncatula, rice or Arabidopsis through etiolation or by extraction with ethanol yielded up to a tenfold increase in fluorescence. Direct evidence that chlorophyll is implicated in the loss of fluorescence from GFP was obtained by mixing solutions of chlorophyll and GFP. At low concentration, fluorescence loss was fourfold greater for chlorophyll b than for chlorophyll a, reflecting their relative interference with GFP excitation and emission. Thus, substantial errors in estimating promoter activity from GFP fluorescence can occur if pigment interference is not considered.

Euclidean Distance transformation is a fundamental technique for the application fields of image understanding and computer vision. Some important characteristics in image analysis such as shape factor, skeleton and medial axis are based upon the distance transformation computation. The lookup table algorithm is based upon the recursive computation structure of the 4N method. Therefore, this algorithm is very fast and is close to the 4N method, which performs as the fastest one among all the comparing algorithms in our experiments. The success of the lookup table algorithm is based upon a checking strategy by error geometry. The error candidates are arranged in order according to their distances to the reference point. In addition, a Local_Array is used to store the y coordinates of the closest foreground pixels above the processing line. Therefore we can find the correct feature point by checking the ordered candidates with the information provided from the Local_Array instead of comparisons among the candidates. In contrast, all the comparing eror-free Euclidean algorithms select their feature points from candidates by time consuming distance comparison.

Thèse de doctorat : Sciences agronomiques : INPL : 2008. / Titre provenant de l'écran-titre.

Zugl.: Speyer, Dt. Hochsch. für Verwaltungswiss., Diss., 2008