Temperature, cloud structure, and dynamics of venus middle atmosphere by infrared remote sensing from pioneer orbiter

Further results from the Venus orbiter radiometric temperature experiment (VORTEX) on the Pioneer orbiter are presented. These are used to characterize the three-dimensional temperature field, the cloud structure, and the dynamics of the 60-to 130-kilometer altitude region of the Venus atmosphere. One of the new discoveries is a "dipole" structure at high latitudes, with two hot spots rotating around the pole, surrounded by banks of cold cloud.     

Clonal micropropagation of mature Larix

Adventitious buds were developed in vitro from stems of elongating short shoots of mature European larch (Larix decidua Mill.). Tissue culture propagule populations thus generated, were similarly remultiplied in vitro. Elongation and rooting were routine. No vitreous or otherwise abnormal shoots were noted.     

Cultured cells of white pine show genetic resistance to axenic blister rust hyphae

Hypersensitive resistance to axenically cultured Cronartium ribicola was displayed by subcultured callus of Pinus lambertiana. Cellular resistance to a destructive rust disease can now be studied at the macromolecular level through use of cloned cells of both host and pathogen in a system amenable to emerging recombinant DNA technology.     

Pioneer 11 infrared radiometer experiment: the global heat balance of jupiter

Data obtained by the infrared radiometers on the Pioneer 10 and Pioneer 11 spacecraft, over a large range of emission angles, have indicated an effective temperature for Jupiter of 125 degrees +/- 3 degrees K. The implied ratio of planetary thermal emission to solar energy absorbed is 1.9+/-0.2, a value not significantly different from the earth-based estimate of 2.5+/-0.5.     

Specific immunosuppression by immunotoxins containing daunomycin

Daunomycin, when conjugated with a targeting antigen by an acid-sensitive spacer, remains inactive at the intravascular pH of 7 but becomes active after cleavage within the acidic lysosomal environment of the target cell. This observation made it possible to construct cytocidal compounds that caused antigen-specific suppression of murine lymphocyte function. When daunomycin was coupled to the hapten conjugate of ovalbumin by an acid-sensitive cis-aconityl group, it caused hapten-specific impairment of immunocompetence in murine B lymphocytes in vitro and in vivo. Furthermore, the response by T lymphocytes to concanavalin A in vitro was selectively eliminated by a conjugate between daunomycin plus the acid-sensitive spacer and a monoclonal antibody specific for T cells.     

Induction of roots on jujube softwood cuttings using Agrobacterium rhizogenes

Summary

Cuttings from trees of jujube (Ziziphus jujuba Mill.), particularly mature ones, root with great difficulty. A greenhouse experiment assessed the effects of two strains of Agrobacterium rhizogenes (A4 and TR105) on softwood cuttings from two sources: ten year old trees of cv. Li and a tree approximately 40 years old of the cv. Contorta. The cuttings were collected and trimmed to 7.5 cm. Ten weeks after inoculation, both strain and source of cutting influenced visible symptoms of infection. Jujube cuttings were more responsive to TR105 than to A4, and the ‘Li’ cuttings were more responsive than ‘Contorta’ cuttings. Strain TR105 was very effective in increasing rooting percentages and root number. ‘Li’ cuttings had better rooting percentages, greater root number, and greater root length than did the ‘Contorta’ cuttings. Inoculation with A. rhizogenes may also possess great potential for promoting adventitious root formation in other difficult woody ornamental or fruit tree species.     

Adventitious micropropagation of mature Larix decidua using dormant versus flushed axillary vegetative buds

Tissues of winter-dormant buds were collected from mature Larix decidua, and used for adventitious shoot organogenesis. Tissues of dormant buds merely died on the cytokinin-supplemented, bud-initiation medium. In contrast, buds allowed to flush under greenhouse conditions subsequently yielded approximately two adventitious shoots per bud explant tissue. These shoots elongated normally and several rooted spontaneously. Microbial contamination of in vitro cultures was negligible using explants from buds orgininally collected in a dormant state.     

Structure-based carbon nanotube sorting by sequence-dependent DNA assembly

Wrapping of carbon nanotubes (CNTs) by single-stranded DNA (ssDNA) was found to be sequence-dependent. A systematic search of the ssDNA library selected a sequence d(GT)n, n = 10 to 45 that self-assembles into a helical structure around individual nanotubes in such a way that the electrostatics of the DNA-CNT hybrid depends on tube diameter and electronic properties, enabling nanotube separation by anion exchange chromatography. Optical absorption and Raman spectroscopy show that early fractions are enriched in the smaller diameter and metallic tubes, whereas late fractions are enriched in the larger diameter and semiconducting tubes.     

Evaluation of promoters and visual markers for transformation of eastern white pine

This report serves to evaluate possible promoters for use in theproduction of transgenic eastern white pine (Pinus strobus L.).Embryogenic cultures of eastern white pine were bombarded with goldparticles coated separately with a variety of gene constructs containingthe UidA -glucuronidase (GUS) or green fluorescentprotein (GFP) reporter gene. Transient expression of the UidAgene, driven by a novel algal virus adenine methyl transferase genepromoter, as well as five other promoters used in angiospermtransformation, were evaluated. The maize alcohol dehydrogenase promoterwas not effective in eastern white pine cultures. The construct with thedoubled Cauliflower Mosaic Virus 35S promoter plus Alfalfa Mosaic Virusenhancer showed the highest levels of expression. GUS expression wasdetected within 24 hours, but decreased after 5 days and was notdetectable 15 days after bombardment. Expression of GUS activity wasrecorded mainly in somatic embryonal heads of various stages ofdevelopment and occasionally in suspensor cells. Similar to GUSexpression, modified green fluorescent protein (GFP) was detected in theembryonal head cells 24 hours after bombardment. GFP-expressingsuspensor cells were both more infrequent and difficult to detect, astheir highly vacuolate nature rendered the GFP presence less visibleagainst the yellow background autofluorescence.