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111.
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Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l−1 IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.  相似文献   
113.

Background  

Facial expressions are important in facilitating human communication and interactions. Also, they are used as an important tool in behavioural studies and in medical rehabilitation. Facial image based mood detection techniques may provide a fast and practical approach for non-invasive mood detection. The purpose of the present study was to develop an intelligent system for facial image based expression classification using committee neural networks.  相似文献   
114.
A system for enhanced induction of somatic embryo-genesis and regeneration of plants from isolated scutellar tissue of wheat has been developed. This system has been successfully used in the development of a simple and reproducible protocol for the production of self-fertile transgenic wheat plants. The procedure is rapid resulting in the production of transgenic plantlets within 12 weeks from initiation of cultures and it avoids the need for establishing long-term callus, cell suspension or protoplast cultures. Somatic embryos regenerated from scutella bombarded with plasmid pBARGUS were selected on L-phosphinothricin (L-PPT) to obtain herbicide-resistant self-fertile transgenic plants. Phosphinothricin acetyltransferase (PAT) activity was observed at varying levels in 50% of the plants selected on L-PPT whereas none of the plants showed β-glucuronidase (GUS) activity. Molecular analysis of PAT-positive plants confirmed stable integration of both bar and gus genes in R0 and R1 progeny plants. Segregation of the PAT activity and herbicide resistance in R1 progeny plants confirmed the Mendelian inheritance of the bar gene. Additionally, isolated scutella bombarded with plasmid DNA containing a gus::nptII fusion gene driven by a rice actin promoter and its first intron were selected in the presence of geneticin to obtain fully fertile transgenic plants. Functional expression of the fusion gene was demonstrated in transgenic plants by GUS and neomycin phospho-transferase (NPTII) enzyme assays. Southern blot analysis confirmed the integration of transgenes into the wheat genome. Histochemical GUS staining showed transmission of the fusion gene to floral organs of primary transformants and confirmed Mendelian segregation of the transgene in R1 progeny.  相似文献   
115.
Mechanical stresses developed in the tissue during sitting or reclining could cause bedsores in paralyzed individuals. Cushions are usually prescribed to redistribute the stresses. Two two-dimensional physical models of the buttock were developed and used to study whether the stress distribution is different with round- and flat-base bone core geometries and to find out whether the relative cushion responses are dependent on loading direction and bone core geometries. In these models, PVC gel simulated the soft tissue and a wooden core simulated the bony prominence. One model had a round-base core and the other had a flat-base bone core. A grid etched on the model allowed strain measurements, and stress calculations. The sharp-base bone core model generated large regions of high shear stress during vertical and inclined loading. However, the round-base core produced maximum compressive stress during vertical loading. The relative cushion responses were dependent on bone core geometry and loading direction.  相似文献   
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