174,326 research outputs found
International Flower Networks: Transparency and Risks in Marketing Channel Choice
No full textTwo thirds of Kenyan cut flowers are marketed through Dutch flower auctions, while the remainder is marketed directly to retailers. Auctions do not restrict the volumes marketed; however price determination is based on a spot market. A Transaction Cost approach is used to investigate the differences in marketing costs between the channels. The results suggest that there are no differences between the channels in terms of uncertainty about prices, finding buyers or transparency of quality standards. Auction growers pay a higher marketing fee but they have significantly fewer office employees and flower varieties compared to growers who market directly.Transaction Costs, Auction, Flowers, Kenya, Netherlands, Agribusiness, International Relations/Trade,
Cognitive deficits of schizophrenia: the flower workshop initiative
No full textAdvancement of research on the neurobiology of the schizophrenic brain has revealed a complex of factors, from genetic tendencies affecting the development of brain structure to functional impairment caused by defective molecular signaling. Recently, the attention of psychiatrists and mental health professionals has been directed to the presence of cognitive deficits, responsible for most of the obstacles to the social insertion of patients.The schizophrenic person has a difficulty to manage the flux of consciousness in social interactions. We address this difficulty with the Flower Arrangement Workshop, a methodology of Psycho-Social Rehabilitation that reduces the vulnerability of the schizophrenic in the social environment. The workshop was offered regularly (18 months) for a group containing 4 schizophrenic subjects.

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
The evolution of flower size and flowering behaviour in plants: The role of pollination and pre-dispersal seed predation
No full textThis thesis describes research into the effects of insect mediated pollination, and pre-dispersal
seed predation, in common species of Asteraceae, varying both between and throughout
growing seasons, and suggests that these exert selective pressures influencing the evolutuion
of both inflorescence size and flowering phenology. Changes in the level of infestation of capitula (by tephritid fly larvae) and in capitulum size
were monitored by twice-weekly collections from populations of common species of
Asteraceae over the course of five years’ flowering, in 2002 to 2006. Seed counts of drying
flower heads were made over the course of the research, identifying levels of seed set in both
uninfested and infested flower heads. A mathematical model was created to investigate the
extended influence of the parameters measured in the field, and predict their influence on
longer term evolution of Asteraceae. Two flower species exhibited both significant levels of infestation, and significant differences
in fecundity. In Leucanthemum vulgare, infestation (by Tephritis neesii) peaked mid-season at
all sites. In Centaurea nigra, infestation (by gall-forming Urophora spp) peaked mid-season,
infestation (by non-gall forming Chaetostomella cylindrica) was lowest in mid-season. In
both species the probability of attack increased with capitulum size, despite a consistent
decline in capitulum size through the season. This suggests that the insects choose larger
capitula from those available at each stage, regardless of absolute size. The presence of
infestation showed a consistent reduction in the level of fecundity in both species. These
findings suggest a selective effect. The mathematical model provides evidence of the long term effects, up to 1000 generations,
of variations in both pollination success, and pre-dispersal seed predation, and suggests that
the values measured in the field are consistent with selective pressures that contribute to the
evolution of both flower size and phenology
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Ants as flower visitors : floral ant-repellence and the impact of ant scent-marks on pollinator behaviour
No full textAs flower visitors, ants rarely benefit a plant, commonly disrupting pollination by deterring other flower
visitors, or stealing nectar. This thesis examines three aspects of ant-flower interactions, focusing on
the occurrence of floral traits that prevent disruption of pollination and a novel means by which ants
may influence pollinator behaviour.
To assess which types of plant species possess ant-repelling floral traits I carried out a survey
of 49 Neotropical plant species. Around a third of these species were repellent to the common
generalist ant Camponotus novograndensis (Formicinae). This repellence was positively correlated
with large nectar volumes within individual flowers. It appears that there has been selection for floral
ant-repellence as a defence against ant thieves in plant species that invest in large volumes of nectar.
In some cases these repellent traits were effective against a wide range of ant species. However, in no
plant species were predacious ants particularly repelled, indicating that there may be little selective
pressure on non-ant-plants to defend potential pollinators from aggressive ants.
To investigate the importance of coevolution in determining the effectiveness of ant-repellents,
a small but diverse range of Mediterranean plant species were tested with the invasive nectar thieving
ant Linepithema humile (Dolichoderinae) and the native but non-nectar thieving ant Messor bouvieri
(Myrmecinae). Responses of both ant species to floral traits were very similar. The ability of some
plants to restrict access to ant species with which they have no evolutionary history may help to
reduce the impact invasive species, as nectar thieves, have on plant-pollinator interactions.
It is reported that flowers recently visited by bees and hoverflies may be rejected for a period
of time by subsequent bee visitors through the detection of scent-marks. Nectar-thieving ants could
potentially influence the foraging decisions of bees in a similar way if they come to associate ant trail
pheromones or footprint hydrocarbons with poor reward levels. However, my empirical work found no
differences were found in bee visitation behaviour between flowers of Digitalis pupurea
(Plantaginaceae), Bupleurum fruticosum (Apiaceae) or Brassica juncea (Brassicaceae) that had been
in contact with ants and control flowers. Ant-attendance at flowers of these species may not reduce reward levels sufficiently to make it worthwhile for bees to incorporate ant scent-marks into foraging
decisions.
Investigations like these into the interactions between ants, flowers and other flower visitors
are essential if we hope to understand the part ants play in pollination ecology, and determine how
ants have helped shape floral evolution
Flower o' the orange : and other tales of bygone days /
No full textFlower o' the orange.--The young conspiracy.--The great white deeps.--My rapier and my daughter.--The great Todescan's secret thrust.--Pomona.--The mirror of the faithful heart.Mode of access: Internet
The adaptive significance of sensory bias in a foraging context: floral colour preferences in the bumblebee Bombus terrestris
No full textInnate sensory biases could play an important role in helping naïve animals to find food. As inexperienced bees are known to have strong innate colour biases we investigated whether bumblebee (Bombus terrestris) colonies with stronger biases for the most rewarding flower colour (violet) foraged more successfully in their local flora. To test the adaptive significance of variation in innate colour bias, we compared the performance of colour-naïve bees, from nine bumblebee colonies raised from local wild-caught queens, in a laboratory colour bias paradigm using violet (bee UV-blue) and blue (bee blue) artificial flowers. The foraging performance of the same colonies was assessed under field conditions. Colonies with a stronger innate bias for violet over blue flowers in the laboratory harvested more nectar per unit time under field conditions. In fact, the colony with the strongest bias for violet (over blue) brought in 41% more nectar than the colony with the least strong bias. As violet flowers in the local area produce more nectar than blue flowers (the next most rewarding flower colour), these data are consistent with the hypothesis that local variation in flower traits could drive selection for innate colour biases
Desenvolvimento das estruturas reprodutivas da macieira (Malus domestica Borkh.) sob diferentes condições climáticas: da formação das gemas à colheita dos frutos
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Recursos Genéticos Vegetais, Florianópolis, 2014.A cultura da macieira apresenta grande importância econômica no cenário mundial visto o grande volume de frutos produzidos e comercializados. No Brasil, a cultura da macieira é explorada principalmente na região Sul do país, devido suas condições climáticas subtropicais temperadas serem as mais parecidas às condições exigidas pela planta na obtenção de produções razoáveis de maçãs. No entanto, dentre os elementos climáticos, a temperatura pode ser considerada um dos fenômenos que mais tem influência sobre a cultura, desde a formação floral até a produção final; sendo um dos fatores responsáveis pelas irregularidades de produções. Diante disto, e com o intuito de gerar conhecimentos e informações sobre a cultura da macieira, este trabalho procurou entender os possíveis efeitos ambientais e climáticos, e seus limites qualitativos e quantitativos, sobre a aclimatação das plantas e de suas estruturas reprodutivas. Durante os anos de 2010 à 2014, foram realizadas as avaliações que envolvem o processo do desenvolvimento floral e reprodutivo de duas cultivares de grande importância econômica mundial, =Gala e =Fuji . Tais avaliações incluíram a caracterização da iniciação e diferenciação morfológica de gemas, da morfologia e biologia floral, e do comportamento fenológico e produtivo das plantas; sendo que as mesmas foram direcionadas sobre as duas principais estruturas de frutificação das plantas, brindilas (gemas axilares e terminal) e esporões. Grande parte do trabalho foi realizado na região de Caçador, localizada no Estado de Santa Catarina a uma latitude de 26°50 S, longitude de 50°58 W e altitude de 950m. No entanto, uma outra região, do Estado de Ohio nos Estados Unidos, a qual, devido as condições climáticas locais, é caracterizada como ideal para o cultivo da macieira, foi utilizada para servir como base de referência para alguns dos estudos aqui realizado. Dez estádios morfológicos foram definidos, do meristema vegetativo à formação dos órgãos florais de inflorescências de gemas da espécie Malus domestica Borkh. A iniciação floral foi influenciada pela cultivar e estrutura. O desenvolvimento floral de gemas da cv. Fuji foi mais rápido que da cv. Gala, e entre as estruturas, os esporões de ambas cultivares formaram-se mais precocemente que as gemas axilares e a terminal das brindilas. A transição floral parece ser regulado por sinais intrínsecos da planta. No entanto, a transição entre os demais estádios de diferenciação parece sofrer considerável influência dos sinais ambientais, principalmente das temperaturas. Flores de macieiras das cvs. Gala e Fuji provenientes de regiões de clima temperado foram mais desenvolvidas morfologicamente que flores de macieira cultivadas sob condições subtropicais. Sob as condições ambientais da região brasileira em estudo, estigmas apresentaram-se mais receptivos na abertura das flores, ou talvez, anteriormente a esta. Diferentemente da região norte americana, onde os estigmas alcançaram a máxima receptividade entre as 24-48 horas após a abertura das flores. Na região de Caçador, flores de gemas terminais de brindilas apresentaram, em geral, melhor qualidade morfológica dos órgãos reprodutivos femininos e masculino. As diferenças encontradas no início de brotação e florescimento entre as estruturas de frutificação dependeram grandemente das condições climáticas do ano em questão. Sob condições de altas temperaturas após o tratamento de quebra de dormência, há maior sincronia fenológica entre as estruturas, e vice e versa. Gemas de esporões necessitam de menor acúmulo térmico para brotarem, principalmente esporões de Gala . Além da baixa frutificação efetiva, gemas axilares de ambas cultivares apresentaram frutos com baixa qualidade morfológica (massa fresca e diâmetro de fruto). Frutos provenientes de terminais de brindilas tendem ser mais arredondados e com maior massa fresca do que frutos das axilares e dos esporões, em ambas as cultivares. Sob as condições climáticas de Caçador, SC, a cultivar Fuji foi mais estável produtivamente que a cv. Gala. O favorecimento de brindilas na cv. Gala, seja através de podas, arqueamento ou outras técnicas específicas, deve ser preconizado quando se deseja garantir boa frutificação efetiva, altas produtividades, e frutos de melhor calibre. Na cv. Fuji, apesar de terminais apresentarem os melhores frutos, a frutificação dos esporões tendeu ser mais estável durante os anos, Para esta cultivar, ambas estruturas poderiam ser preconizadas.Abstract : Apples are one of the most valuable fruit crops in the world because of the significant amount produced and commercialized. In Brazil, apples are mainly grown in the south since these areas possess the most suitable climatic conditions for reasonable productions. Among climate elements temperature may be considered the most significant phenomenon affecting the process of fruit production, from flower bud formation through harvest. Also, it is one of the factors responsible for irregular cropping. Thereafter, this work tried to understand the possible environmental and climatic effects, qualitative and quantitative limitations, on the acclimation of both trees and fruiting habits. From 2010 to 2014, the process of flower and fruit development of the two main apple cultivars, Gala and Fuji, were evaluated. Measurements were done separately on the three types of buds, spurs, and both terminal and axillary buds of one year shoots. Morphological characterization of bud initiation and differentiation, flower biology and morphology, flowering phenology and fruit production were studied. The trials were mainly carried under the Brazilian conditions, in Caçador, SC, Brazil (latitude 26°50?S, longitude 50°58?W, altitude of 950m). However, a second region located in Ohio State, in the United States, was included as a reference for some of the studies such as bud differentiation and flower biology, since it shows great climate conditions for growing apples. Ten morphological bud stages of Malus domestica Borkh were defined, from the vegetative meristem to floral organs differentiation. Flower initiation was affected by cultivar and bud type. Floral development of =Fuji? buds was faster than =Gala? buds. Among the buds types, flower initiation and differentiation occurred first in spurs, then in axillary and terminal buds, successively. Floral transition seems to be triggered by intrinsic signals; whereas the transition between the stages seems to be considerably affected by environmental conditions, mainly temperatures. The morphological development of apple flowers =Gala? and =Fuji? were greater under temperate climate than subtropical conditions. Under the environmental conditions of the region in south of Brazil stigmas reached the optimumreceptivity at anthesis or earlier; whereas in the region in North America pollen reached a maximum germination 24-48 hours after flower opening. In Caçador, terminal flowers on one year old long shoot showed higher morphological qualities of the female and male floral organs than spurs and axillary. Flowering and bud break onset of the different bud types greatly depended on the year assessed; warmer springs induced to a synchronized onset between the different buds. Spur buds requires less heat-unit accumulation at budbreak, specially =Gala? spur buds. In general, axillary buds of both cultivars showed low fruitset and produced smaller fruits (weight and diameter). Terminal buds on long shoots of both cultivars induced rounder and heavier fruits than axillary and spur buds. Under the climate conditions of Caçador =Fuji? was productively more stable than =Gala?. In order to ensure good fruitset, high yields and larger fruits, one year shoots should be preferred in the tree management practices of =Gala? such as pruning, bending or other techniques. Although in =Fuji?, terminal buds of long shoots produced high quality fruits, the fruitset of spurs tended to be stable among years; therefore, both bud types should be preconized
Photonic quantum ring flower laser of whispering cave mode
No full textA flower-type photonic quantum ring (PQR) laser for enhanced output power of about five times that expected from circular PQR lasers of the same size has been designed and fabricated. The multi-petal flower design, combining concave and convex whispering cave modes, increases the overall quantum wire length of the emitting PQR within the same device area.X111sciescopu
- …
