5,666 research outputs found
Microspore derived embryo formation and doubled haploid plant production in broccoli (Brassica oleracea L. var italica) according to nutritional and environmental conditions
In cell culture, the maintenance of proper growing conditions is a key approach for improving the formation of embryos, and is useful in the production of doubled haploid (DH) plants. Optimal nutritional and environmental conditions for the microspore culture of Brassica oleracea L. var italica were determined in order to reduce time and effort in breeding. The optimal conditions for microspore embryo formation differed depending on genotype. Microspore-derived embryos (MDE) formation was influenced by the strength of the NLN medium, the microelement and sugar concentration, and the heat shock temperature and period. The 0.5XNLN liquid medium was the most favorable for MDE formation. The most efficient formation of MDE was observed in the 0.5X NLN liquid medium, without the addition of microelements. When 13 or 15% sucrose was added to the 0.5X NLN liquid medium, the amount of normal MDE formation increased. The optimum heat shock temperature and period for MDE formation was 32.5°C and 24 h, respectively. A polyploidy test indicated that 30% of the microspore derived plants were diploid throughout the embryogenesis process.Key words: Embryogenesis, heat shock, microelements, NLN medium, polyploidy test
Effects of variable attachment shapes and aligner material on aligner retention.
OBJECTIVE: To evaluate the retention of four types of aligners on a dental arch with various attachments. MATERIALS AND METHODS: For this study, three casts were manufactured, two of which contained attachments (ellipsoid and beveled), and one without any attachments to serve as a control. Four types of aligners were thermoformed: Clear-Aligner (CA)-soft, CA-medium, and CA-hard, with various thicknesses, and Essix ACE. Measurements of vertical displacement force during aligner removal were performed with the Gabo Qualimeter Eplexor. Means and standard deviations were next compared between different aligner thicknesses and attachment shapes. RESULTS: CA-soft, CA-medium, and CA-hard did not present a significant increase in retention, except when used in the presence of attachments. Additionally, CA-medium and CA-hard required significantly more force for removal. Essix ACE demonstrated a significant decrease in retention when used with ellipsoid attachments. The force value for Essix ACE removal from the cast with beveled attachments was comparable to that of CA-medium. Forces for aligner removal from the model without attachments showed a linear trend. Essix ACE did not show a continuous increase in retention for each model. Overall, ellipsoid attachments did not present a significant change in retention. In contrast, beveled attachments improved retention. CONCLUSIONS: Ellipsoid attachments had no significant influence on the force required for aligner removal and hence on aligner retention. Essix ACE showed significantly less retention than CA-hard on the models with attachments. Furthermore, beveled attachments were observed to increase retention significantly, compared with ellipsoid attachments and when using no attachments
Relaxed 2-D Principal Component Analysis by Norm for Face Recognition
A relaxed two dimensional principal component analysis (R2DPCA) approach is
proposed for face recognition. Different to the 2DPCA, 2DPCA- and G2DPCA,
the R2DPCA utilizes the label information (if known) of training samples to
calculate a relaxation vector and presents a weight to each subset of training
data. A new relaxed scatter matrix is defined and the computed projection axes
are able to increase the accuracy of face recognition. The optimal -norms
are selected in a reasonable range. Numerical experiments on practical face
databased indicate that the R2DPCA has high generalization ability and can
achieve a higher recognition rate than state-of-the-art methods.Comment: 19 pages, 11 figure
On chip interconnects for multiprocessor turbo decoding architectures
International audienc
Monte Carlo Simulation of Sinusoidally Modulated Superlattice Growth
The fabrication of ZnSe/ZnTe superlattices grown by the process of rotating
the substrate in the presence of an inhomogeneous flux distribution instead of
successively closing and opening of source shutters is studied via Monte Carlo
simulations. It is found that the concentration of each compound is
sinusoidally modulated along the growth direction, caused by the uneven arrival
of Se and Te atoms at a given point of the sample, and by the variation of the
Te/Se ratio at that point due to the rotation of the substrate. In this way we
obtain a ZnSeTe alloy in which the composition varies
sinusoidally along the growth direction. The period of the modulation is
directly controlled by the rate of the substrate rotation. The amplitude of the
compositional modulation is monotonous for small angular velocities of the
substrate rotation, but is itself modulated for large angular velocities. The
average amplitude of the modulation pattern decreases as the angular velocity
of substrate rotation increases and the measurement position approaches the
center of rotation. The simulation results are in good agreement with
previously published experimental measurements on superlattices fabricated in
this manner
Spin-density-wave transition of (TMTSF)PF at high magnetic fields
The transverse magnetoresistance of the Bechgaard salt (TMTSF)PF has
been measured for various pressures, with the field up to 24 T parallel to the
lowest conductivity direction c. A quadratic behavior is observed in
the magnetic field dependence of the spin-density-wave (SDW) transition
temperature . With increasing pressure,
decreases and the coefficient of the quadratic term increases. These results
are consistent with the prediction of the mean-field theory based on the
nesting of the quasi one-dimensional Fermi surface. Using a mean field theory,
for the perfect nesting case is estimated as about 16 K. This
means that even at ambient pressure where is 12 K, the SDW
phase of (TMTSF)PF is substantially suppressed by the
two-dimensionality of the system.Comment: 11pages,6figures(EPS), accepted for publication in PR
Economical Valuation of Hypothetically Constructed Washland around a Wetland
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
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