201,803 research outputs found
Coffee berry disease in Kenya
No full textData are presented on research in Kenya in 1964 - 1969 on anatomical, mycological, epidemiological, chemical control and cultural aspects of coffee berry disease, Colletotrichum coffeanum Noack, of Coffea arabica L. The pathogen causes flower and berry losses and was found in branches where it occupied clearly defined areas of the cortex just before or after formation of the first phellogen. Saprophytic Colletotrichum spp. inhabit bark areas with more periderms in the cortex. No relationship could be found in Kenya between Glomerella cingulata (Stonem.) Sp. & Schr., the perfect stage of most of the saprophytic Colletotrichum bark components, and C. coffeanum . The seasonal fluctuations in pathogenicity in the bark population of C. coffeanum could be assessed and compared with the total sporulating capacity of the bark population of all Colletotrichum spp. Formerly the level of this total sporulating capacity, or 'inoculum potential' as it was then called, was used as an indication when pre-rain copper sprays had to be applied and how effectively the fungicide had reduced the bark inoculum. Based on these data the recommendations for chemical control were changed from pre-rain fungicide applications, to a spraying regime well into the rainy period, the accent being on protection of the berries rather than on a reduction of the bark inoculum. The fungicide Ortho Difolatan proved to be more effective than copper based compounds. Cultural practices, like the application of high levels of fertilizers, manure and mulch and rigid pruning practices, had no effect on the level of C. coffeanum in branches. Copper containing fungicides pushed the Colletotrichum balance in favour of C. coffeanum . Berries from non-copper sprayed coffee fields were less susceptible to standard conidial suspensions of C. coffeanum than berries from copper sprayed trees. A similar effect of fungicides should be considered in South and Central American coffee growing countries, where the application of fungicides has increased tremendously since the occurrence of Hemileia vastatrix Berk. et Br. in Brazil
Polarization singularities in isotropic random vector waves
No full textFollowing Nye & Hajnal, we explore the geometry of complex vector waves by regarding them as a field of polarization ellipses. Singularities of this field are the C lines and L lines, where the polarization is purely circular and purely linear, respectively. The singularities can be reinterpreted as loci of photon spin 1 (C lines) and 0 (L lines). For Gaussian random superpositions of plane waves equidistributed in direction but with an arbitrary frequency spectrum, we calculate the density (length per unit volume) of C and L lines
Berry Strain Gage Extensometer
No full textHerman C. Berry developed this strain gage around 1910 for measuring deformations in materials. It superseded the older Howard strain gage. By 1912 the Berry gage was in turn superseded by the Whittemore strain gage, though the Berry gage was still used throughout the 1920s. The Berry gage was designed to be applied to existing structures such as plates or structural shapes. Holes were drilled in the structure and the points of the gage fitted into the holes. As the gage was applied by hand, one gage could be used to survey a pattern of holes as the structure is loaded. Professor Berrys original gage used a screw micrometer to sense the movement of the magnifying lever.9 x 21 x 2 cm; 11 x 2 x .1 cmMade by F. F. Metzger Phila. Strain-Gage H. C. Berry Pat. 12.17.1
Berry Strain Gage Extensometer
No full textHerman C. Berry developed this strain gage around 1910 for measuring deformations in materials. It superseded the older Howard strain gage. By 1912 the Berry gage was in turn superseded by the Whittemore strain gage, though the Berry gage was still used throughout the 1920s. The Berry gage was designed to be applied to existing structures such as plates or structural shapes. Holes were drilled in the structure and the points of the gage fitted into the holes. As the gage was applied by hand, one gage could be used to survey a pattern of holes as the structure is loaded. Professor Berrys original gage used a screw micrometer to sense the movement of the magnifying lever.6 x 16 x 2 cmMade by F. F. Metzger Phila. Strain-Gage H. C. Berry; Pat. 5. 31. 1
Berry Strain Gage Extensometer
No full textThe Berry strain gage was an American development in the field of extensometers -- mechanical devices designed to measure small deformations in materials. It superseded the older Howard strain gage of 1910 and the Whittemore strain gage of 1912. The Berry gage was designed to be applied to existing objects such as plates or structural shapes. Holes were drilled in the object and the points of the gage fitted into the holes. As the gage was applied by hand, one gage could be used to survey a pattern of holes as the object is loaded. The original gage designed by Professor Herman C. Berry of the University of Pennsylvania used a screw micrometer to sense the movement of the magnifying lever. The artifact was used at the National Bureau of Standards throughout the 1920s.16 x 54 x 2 c
Berry Strain Gage Extensometer
No full textThe Berry strain gage was an American development in the field of extensometers -- mechanical devices designed to measure small deformations in materials. It superseded the older Howard strain gage around 1910 and was in turn superseded by the Whittemore strain gage in 1912. The Berry gage was designed to be applied to existing objects such as plates or structural shapes. Holes were drilled in the object and the points of the gage fitted into the holes. As the gage was applied by hand, one gage could be used to survey a pattern of holes as the object is loaded. The original gage designed by Professor Herman C. Berry of the University of Pennsylvania used a screw micrometer to sense the movement of the magnifying lever. The artifact was used throughout the 1920s.12 x 55 x 1 c
Ethylene signalling receptors and transcription factors over the grape berry development: gene expression profiling
No full textThe ethylene signalling pathway has never been fully described in grapes. Regarded as a non-climacteric fruit, grape berry seems to ripen independently to ethylene, however 1-methylcyclopropene (1-MCP), a specific inhibitor of ethylene receptors has been shown to alter berry ripening processes. Here, we report profiles of transcript abundance of various receptors and transcription factors, associated with ethylene signalling, throughout berry development. Transcript abundance of ortholog VvETR2 gene showed a transient peak at the inception of ripening in 'Cabernet Sauvignon' berries coinciding with an internal ethylene peak, prior to colour changes. The transcripts of other orthologs such as VvRTE1 and VvEIN4 steadily increased over the berry development, while VvERS1 ortholog transcripts exhibited a peak of accumulation only when the berries were fully coloured. Finally, mRNAs of two transcription factors, VvEIN3 and VvMADS4, showed strong accumulation during the late phase of berry ripening. We also observed inflections of mRNA accumulation after incubating berry clusters with ethylene and 1-MCP (inhibitor of ethylene action). The main effect was observed with VvEIN3 transcripts that showed a significant up-regulation after incubation with 1-MCP. Furthermore, other transcript levels (VvETR2 and VvCTR1) were also increased by exogenous ethylene, once the colour change was initiated (i.e. 10 to 11 weeks after bloom). Some studies have already indicated that non-climacteric fruits shared signalling pathways with climacteric fruits. However, most differences between these ripening classifications remain poorly described at the genetic/molecular level. This data set will contribute to a better understanding on potential involvements of ethylene signalling in a non-climacteric fruit such as grape berry
Vascular functioning and development of the kiwifruit berry (Actinidia deliciosa)
No full textThe aim of this study was to understand kiwifruit berry development and the role of cell turgor and the phloem unloading pathway in development. Important aspects of berry development include the size of the fruit and its composition. The fresh weight growth curve of the kiwifruit berry was shown to be double sigmoid in shape. Dry weight accumulated linearly for the initial 139 days after anthesis (DAA). At this time the soluble solids concentration began to increase. Berry firmness was measured using two methods, with the penetrometer and with a new non-destructive method, utilising skinfold callipers. Both methods exhibited similar results, indicating that the skin callipers may be useful in the future for non-destructive berry rheological measurements.
Cell turgor was measured indirectly from measurements of symplasmic and apoplasmic solute potentials, and the matric potential of the berry. Apoplasmic sap, required to measure the apoplasmic solute potential, was extracted using two different methods the pressure chamber and through centrifugation. Measurements of sap osmotic potential suggest that the sap extracted using the centrifuge was contaminated with symplasmic sap, resulting in a negative cell turgor estimate. However, the pressure chamber technique provided apoplasmic sap that produced a more accurate estimate of cell turgor. Direct estimates of cell turgor were only obtained from the midpoint of the growing season because of contamination with symplasmic sap, but the values obtained were comparable to literature values for developing grape and tomato berries.
The phloem unloading pathway in the fruit was investigated using a symplasmic tracer dye, carboxyfluorescein diacetate coupled with 14C labelling and autoradiography. The phloem unloading pathway was symplasmic until 91 DAA when the dye was restricted to the phloem cells only, indicating a change to an apoplasmic pathway. However, due to the lack of functional unloading seen in radiolabelled samples, a change in the phloem unloading pathway could not be confirmed
Resume of Michael C. Berry, 1994
No full textNaval Postgraduate School Faculty Resume[I]n April of 1996, [Berry] transferred to the Naval Postgraduate School as the Safety and Occupational Health Manager with duties commencing 7 Feb 1994
Berry Strain Gage
No full textThis artifact is a 2 inch Berry strain gage. The Berry strain gage was an American development in the field of extensometers -- mechanical devices designed to measure small deformations in materials. It superseded the older Howard strain gage around 1910 and was in turn superseded by the Whittemore strain gage in 1912. The Berry gage was designed to be applied to existing objects such as plates or structural shapes. Holes were drilled in the object and the points of the gage fitted into the holes. As the gage was applied by hand, one gage could be used to survey a pattern of holes as the object is loaded. The original gage designed by Professor Herman C. Berry of the University of Pennsylvania used a screw micrometer to sense the movement of the magnifying lever.9 x 16 x 2 cmMade by / F.F. Metzger / Phila. / Strain-Gage / H.C. Berry / Pat. 12.17.1
- …
