884 research outputs found
The value of alar sprays for apples
ALAR* is a growth retardant which has been die subject of intensive research in other countries. It tends to slow both fruit growth and ripening and to reduce shoot extension.
Overseas and local investigations with apples have shown that Alar will reduce preharvest drop, restrict shoot growth and increase flower bud formation for the following season
Stop-drop sprays for Jonathan and Delicious apples
STOP-DROP sprays prevent excessive pre-harvest drop of Jonathan and Delicious apples.
Recent research has thrown more light on the best methods of employing these materials.
TWO CHEMICALS used as stop-drop sprays are available commercially in Western Australia. One of these, alpha napthalene acetic acid (NAA), is also well known as a thinning spray for apples
Early hail marks on apples do not grow out
ALTHOUGH the 1964/65 season brought a record crop with a good proportion of high quality fruit, the year was marred by several violent hailstorms in separate parts of the South-West
Fertiliser recommendations for citrus : detailed fertilizer programmes for citrus growers
CITRUS growers should adopt a well balanced fertiliser programme to safeguard tree health, cropping and fruit quality. While moderate dressings are a wise insurance in most situations the rates required vary with tree age and soil type.
The recommendations are given in detail in the tables in this article
Fertiliser recommendations for apple trees
THE increased use of irrigation and chemical thinning in apple orchards and the planting of trees in light soils have resulted in responses to regular fertiliser dressings
Microtopography Matters: Belowground CH4 Cycling Regulated by Differing Microbial Processes in Peatland Hummocks and Lawns
Water table depth and vegetation are key controls of methane (CH4) emissions from peatlands. Microtopography integrates these factors into features called microforms. Microforms often differ in CH4 emissions, but microform-dependent patterns of belowground CH4 cycling remain less clearly resolved. To investigate the impact of microtopography on belowground CH4 cycling, we characterized depth profiles of the community composition and activity of CH4-cycling microbes using 16S rRNA amplicon sequencing, incubations, and measurements of porewater CH4 concentration and isotopic composition from hummocks and lawns at Sallie\u27s Fen in NH, USA. Geochemical proxies of methanogenesis and methanotrophy indicated that microforms differ in dominant microbial CH4 cycling processes. Hummocks, where water table depth is lower, had higher porewater redox potential (Eh) and higher porewater Ξ΄13C-CH4 values in the upper 30 cm than lawns, where water table depth is closer to the peat surface. Porewater Ξ΄13C-CH4 and Ξ΄D-CH3D values were highest at the surface of hummocks where the ratio of methanotrophs to methanogens was also greatest. These results suggest that belowground CH4 cycling in hummocks is more strongly regulated by methanotrophy, while in lawns methanogenesis is more dominant. We also investigated controls of porewater CH4 chemistry. The ratio of the relative abundance of methanotrophs to methanogens was the strongest predictor of porewater CH4 concentration and Ξ΄13C-CH4, while vegetation composition had minimal influence. As microbial community composition was strongly influenced by redox conditions but not vegetation, we conclude that water table depth is a stronger control of belowground CH4 cycling across microforms than vegetation
Small Heat Shock Proteins Potentiate Amyloid Dissolution by Protein Disaggregases from Yeast and Humans
The authors define how small heat-shock proteins synergize to regulate the assembly and disassembly of a beneficial prion, and then they exploit this knowledge to identify the human amyloid depolymerase
The Mammalian Disaggregase Machinery: Hsp110 Synergizes with Hsp70 and Hsp40 to Catalyze Protein Disaggregation and Reactivation in a Cell-Free System
Bacteria, fungi, protozoa, chromista and plants all harbor homologues of Hsp104, a AAA+ ATPase that collaborates with Hsp70 and Hsp40 to promote protein disaggregation and reactivation. Curiously, however, metazoa do not possess an Hsp104 homologue. Thus, whether animal cells renature large protein aggregates has long remained unclear. Here, it is established that mammalian cytosol prepared from different sources possesses a potent, ATP-dependent protein disaggregase and reactivation activity, which can be accelerated and stimulated by Hsp104. This activity did not require the AAA+ ATPase, p97. Rather, mammalian Hsp110 (Apg-2), Hsp70 (Hsc70 or Hsp70) and Hsp40 (Hdj1) were necessary and sufficient to slowly dissolve large disordered aggregates and recover natively folded protein. This slow disaggregase activity was conserved to yeast Hsp110 (Sse1), Hsp70 (Ssa1) and Hsp40 (Sis1 or Ydj1). Hsp110 must engage substrate, engage Hsp70, promote nucleotide exchange on Hsp70, and hydrolyze ATP to promote disaggregation of disordered aggregates. Similarly, Hsp70 must engage substrate and Hsp110, and hydrolyze ATP for protein disaggregation. Hsp40 must harbor a functional J domain to promote protein disaggregation, but the J domain alone is insufficient. Optimal disaggregase activity is achieved when the Hsp40 can stimulate the ATPase activity of Hsp110 and Hsp70. Finally, Hsp110, Hsp70 and Hsp40 fail to rapidly remodel amyloid forms of the yeast prion protein, Sup35, or the Parkinson's disease protein, alpha-synuclein. However, Hsp110, Hsp70 and Hsp40 enhanced the activity of Hsp104 against these amyloid substrates. Taken together, these findings suggest that Hsp110 fulfils a subset of Hsp104 activities in mammals. Moreover, they suggest that Hsp104 can collaborate with the mammalian disaggregase machinery to rapidly remodel amyloid conformers
Measurement of Trace Water Vapor in a Carbon Dioxide Removal Assembly Product Stream
The International Space Station Carbon Dioxide Removal Assembly (CDRA) uses regenerable adsorption technology to remove carbon dioxide (COP) from cabin air. Product water vapor measurements from a CDRA test bed at the NASA Marshall Space Flight Center were made using a tunable infrared diode laser differential absorption spectrometer (TILDAS) provided by NASA Glenn Research Center. The TILDAS instrument exceeded all the test specifications, including sensitivity, dynamic range, time response, and unattended operation. During the COP desorption phase, water vapor concentrations as low as 5 ppmv were observed near the peak of CO2 evolution, rising to levels of approx. 40 ppmv at the end of a cycle. Periods of high water concentration (>100 ppmv) were detected and shown to be caused by an experimental artifact. Measured values of total water vapor evolved during a single desorption cycle were as low as 1 mg
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