1,287 research outputs found
Flowers through insect eyes: the contribution of pollinator vision to the evolution of flower colour
No full textPhDFlowers’ colours are an essential element of their ability to attract visits from
pollinators. However, the colours as they appear to human observers can differ
substantially from their appearance to insect pollinators, and so it is essential to consider
pollinator vision in any study of the ecology of flower colour.
In this thesis I describe how I have overseen the development of an online database to
provide accurate information on floral spectral reflectance measured without human
observational bias. This resource allows a more accurate consideration of flower colours
in future studies, and permits investigations of flower colours within and across
habitats. Using the records in this database, I analysed flowers from two European
habitats for spatial or temporal changes, modelling the colours according to insect visual
perception. I discovered that the insect-colour composition of the plant communities
does not change either along an altitudinal gradient or throughout the year. These novel
and ecologically-relevant analyses contradict previous observational studies, but support
the theory of a pollination “market” in which flowers compete for pollinator visitation.
I then describe my experimental investigations into the visual capabilities of two
pollinators and how this may relate to what colours of flowers they visit. Firstly I study
the foraging behaviour of bees under spatially inconsistent illumination and how this
impacts on their choice behaviour. I revealed patchy light can have measurable effects
on bee foraging behaviour: they intentionally choose familiar over unfamiliar
illumination, which may impact on the flowers they visit in complex natural
environments. Secondly, I detail the new evidence for a red-sensitive photoreceptor in
South African monkey beetles, a major pollinator in a habitat containing many longwavelength-
reflecting flowers, which are not classically “attractive” to bees.
Throughout this thesis, I explore how pollinator vision has shaped the evolution of
flower colours in different contexts.Biotechnology and Biological Science Research Council.
Royal Botanical Gardens Kew (BBS/S/L-2005/12155A
Growth and characterisation of titanium sulphide nanostructures by surface-assisted vapour transport methods; from trisulphide ribbons to disulphide nanosheets
No full textSurface Assisted Chemical Vapour Transport (SACVT) methods have been employed to grow nanostructures of titanium disulphide (TiS2) and titanium trisulphide (TiS3). SACVT reactions occur between titanium and sulphur powders to form TiSx species transported in the vapour phase to grow nanometric flower-like structures on titanium-coated silica substrates. The evolution of structure and composition has been followed by powder X-ray diffraction, electron microscopy and Raman spectroscopy. At 1 : 2 Ti : S ratios, the size and shape of the hexagonal 1T-TiS2 titanium disulphide structures formed can be varied from flower-like growths with 'petals' formed from nanosheets 10 nm thick to platelets microns across. Increasing the proportion of sulphur (Ti : S 1 : 4) enables TiS3 flower-like structures composed of radiating nanoribbons to grow at elevated temperatures without decomposition to TiS2. TEM/SAED suggests that individual trisulphide ribbons grow along the [010] direction. Magnetic properties of the disulphide nanomaterials have been determined using SQUID magnetometry and Raman spectra for disulphides suggest that their crystal and electronic structures may be more complex than expected for bulk, stoichiometric, CdI2-structured TiS2
Mt. Borah
No full textA mountain rises above some wooded foothills. Description reads: ""Telephoto view of Mt. Borah (12,655 ft. elevation) highest mountain in Idaho, taken from Grazing Service CCC Camp Chilly #111. Forest: Challis, State: Idaho, Date: 7/1940, Author: P.S. Bieler""
Hyndman Peak
No full textA mountain is visible across a valley and between two hills. Description reads: ""Hyndman Peak (12,078 ft. elevation) as seen from upper Big Lost River near Kane Creek on Forest Road to Ketchum. Forest: Challis, State: Idaho, Date: 7/1940, Author: P.S. Bieler""
Mechanism of Bioactivity of Peltophorum Ferrugineum Flower Extracts
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Flower Initiation Pattern, Developmental Stages, and Seed Morphology of Paraphalaenopsis Labukensis P.S. Shim, A. Lamb & C.L. Chan, An Endangered Orchid in Sabah
No full textBackground: Paraphalaenopsis labukensis P.S. Shim, A. Lamb & C.L. Chan is a monopodial epiphytic species that can only be found in Sabah. P. labukensis orchids have unique characteristics in that it has a long floral lifespan as compared to other orchid species. The flower developmental pattern of P. labukensis greatly influenced capsule formation and seed maturation. Objective: The present research was conducted to record the initiation of flower initiation, and floral morphology, and to observe the flowering and capsule development, as well as the effect of different capsule ages on asymbiotic seed germination. Methods: A total of three individual plants of P. labukensis were observed. The flowering stages were characterized by quantitative parameters such as length of inflorescence, diameter, and length of buds, the number of flowers produced, and the length of the capsule formed. All the data were recorded through direct observation. Results: Overall, twelve morphological landmark that define each stage of floral development was recorded. Based on the observation, P. labukensis inflorescence was asymmetric and in the shape of a panicle. The number of flowers varied among inflorescences, ranging from 3–5, that blossomed at different times. Furthermore, early capsules appeared 40–90 days after pollination (DAP). Then, 120 DAP of the capsule was selected as the most suitable capsule age for germination as it had reached its maturation period. Conclusion: Identifying the duration of the whole flowering developmental process will aid in the production of capsules to attain a reliable and adequate seed source for in vitro seed germination
Author Correction: New perspectives on Neanderthal dispersal and turnover from Stajnia Cave (Poland)
No full textThe Author contributions section now reads:“W.N., A.N. and S.T. designed research; A.P., M.H., W.N., S.B., M.U., A.M., H.F., M.D.B., P.S., K.S., M.Ż., A.W., A.N. and S.T. performed research; A.P., M.H., W.N., S.B., M.U., A.M., H.F., M.D.B., P.S., K.S., M.Ż., A.W., A.N. and S.T. analysed data; A.P., M.H., S.T., W.N. and S.B. wrote the paper with the collaboration of all the co-authors.
P.S.: Further Thoughts from a Lifetime of Listening
No full textThe pieces in P.S. reflect Studs’s wide-ranging interests and travels, as well as his abiding connection to his hometown, Chicago. Here we have a fascinating conversation with James Baldwin, possibly Studs’s finest interview with an author; pieces on the colorful history and culture of Chicago; vivid portraits of Studs’s heroes and cohorts (including an insightful and still timely interview with songwriter Yip Harburg, known for his “Brother, Can You Spare a Dime”); and the transcript of Studs’s famous broadcast on the Depression, the very moving essence of what was to become Hard Times.https://corescholar.libraries.wright.edu/dlpp_all/1204/thumbnail.jp
Septoria Leaf Spot Reduces Flower Bud Set and Yield Potential of Rabbiteye and Southern Highbush Blueberries
No full textIn field trials on Premier rabbit eye blueberry, individual shoots were selected and tagged in the fall of 2001, 2002, and 2003 to quantify the effects of Septoria leaf spot severity and disease-induced premature defoliation on flower bud set and return yield. Experiments were carried out similarly on Blue crisp southern high bush blueberry using shoots tagged after fruit harvest in the summer of 2002 and 2003. Leaves on the distal 20-cm segments of these shoots were monitored for disease severity (number of spots per leaf) through the remainder of the growing season; at the same time, defoliation (expressed as the proportion of nodes with missing leaves) was recorded for each of the shoot segments. Flower bud set was assessed subsequently in winter or early spring, and berries were harvested as they matured the following summer to determine return yield. For both cultivars, higher flower bud numbers were more likely to occur on shoots with lower disease levels the previous fall (P ≤ 0.0462 based on a Kolmogorov-Smirnov test). The data further showed that flower bud set potential (i.e., the maximum number of buds on shoots within a given disease severity range) decreased linearly as disease severity increased (r2 ≥ 0.926, P ≤ 0.0005). Based on the slope of this relationship, flower bud set potential decreased by one bud per shoot as disease severity the previous fall increased by 18 and 12 spots per leaf for Premier and Blue crisp, respectively. Relationships between yield and disease variables were similar to those of flower bud numbers and disease, except that the decrease in yield potential (i.e., the maximum fruit weight per shoot within a given disease severity range) was less gradual than for flower bud set potential. On Premier, yield potential dropped markedly and significantly as disease severity the previous fall exceeded about 50 to 60 spots per leaf on average (P < 0.0001 based on a Kruskal-Wallis test). Evidence for such a threshold effect was weaker on Blue crisp, presumably because of the lower number of data points for this cultivar combined with lower yields due to poor pollination
Author Correction:A 41,500 year-old decorated ivory pendant from Stajnia Cave (Poland)
No full textCorrection to: Scientific Reports https://doi.org/10.1038/s41598-021-01221-6, published online 25 November 2021The original version of this Article contained errors in the author list where Marjolein D. Bosch was omitted from the author list, and Mikołaj Urbanowski was incorrectly listed as an author of the original Article, and has subsequently been removed.The Author contributions section now reads:“S.T. W.N. and A.N. conceived the project; S.T., W.N., A.P., M.B., S.C., M.D., H.F., A.M., M.D. B., D.P., M.P.R., C.M.R., V.S-M., G.M.S., P.S., M.S., K.S., A.V., F.W., H.W., A.W., M.Z., S.B., A.N., J-J. H., performed research; S.T., A.P., W.N., M.B., M.D.B., S.C., M.D., H.F., A.M., D.P., M.P.R., C.M.R., V.S-M., G.M.S., P.S., M.S., K.S., A.V., F.W., H.W., A.W., M.Z., S.B., A.N., J-J. H. analysed all archaeological data; S.T. and A.P. wrote the paper with the collaboration of all the co-authors.”The original Article and its accompanying Supplementary Information file have been corrected
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