Relevant bibliographies by topics / Pulvinus

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Pulvinus'

Author: Grafiati
Published: 4 June 2021
Last updated: 17 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Pulvinus.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Pulvinus"

1

Sheriff, DW, and MM Ludlow. "Diaheliotropic Responses of Leaves of Macroptilium atropurpureum cv. Siratro." Functional Plant Biology 12, no. 2 (1985): 151. http://dx.doi.org/10.1071/pp9850151.

Full text
Abstract:
Diaheliotropic movements in Macroptilium atropurpureum cv. Siratro caused the adaxial surfaces of leaflets to orient towards a light by the flexing of secondary pulvini at the base of the leaflets, and to a lesser extent by petiole bending and flexing of the primary pulvinus at the base of the petiole. Secondary pulvini flexed more in response to light than did primary pulvini. This flexing was in response to blue light such that the illuminated side of the pulvinus contracted, and the leaflet reoriented with its adaxial surface facing the light. This response was enhanced by the following: a light gradient along the length of the illuminated surface of the pulvinus, the presence of additional low-intensity diffuse light, a photon irradiance greater than 0.5 mmol m-2 s-1, and a change of photon irradiance. The abaxial surface of a pulvinus was more sensitive to light than was its adaxial surface. The stimulus for movement was transmitted from an illuminated primary pulvinus to the shaded secondary pulvini of the same leaf, and this caused re-orientation of both individual leaflets and the whole leaf. Similarly, a stimulus was transmitted to the primary pulvinus from secondary pulvini (or from the adjacent petiole) when illuminated, resulting in a deflection of the petiole by the primary pulvinus and re-orientation of the adaxial surface of the whole leaf towards the light. Secondary pulvini have the ability to move individual leaflets in three dimensions because the plane of the leaflet is at right angles, in two dimensions, to the axis of the distal end of the pulvinus. Terminal leaflets showed a greater three-dimensional movement than did lateral leaflets. Movement of a light through large angles resulted in leaflet re-orientation proportional to, but less than, the change in angle of the light. On the other hand, secondary pulvini caused leaflets to track, though imperfectly, a light source that simulated the movement of the sun. A circumnutational circadian rhythm is partly responsible for the diaheliotropic movements of Siratro leaves outdoors, and the ability of an individual leaflet to track the sun depends upon its orientation with respect to the sun.
APA, Harvard, Vancouver, ISO, and other styles
2

Kong, Yiming, Zhe Meng, Hongfeng Wang, Yan Wang, Yuxue Zhang, Limei Hong, Rui Liu, et al. "Brassinosteroid homeostasis is critical for the functionality of the Medicago truncatula pulvinus." Plant Physiology 185, no. 4 (January 26, 2021): 1745–63. http://dx.doi.org/10.1093/plphys/kiab008.

Full text
Abstract:
Abstract Many plant species open their leaves during the daytime and close them at night as if sleeping. This leaf movement is known as nyctinasty, a unique and intriguing phenomenon that been of great interest to scientists for centuries. Nyctinastic leaf movement occurs widely in leguminous plants, and is generated by a specialized motor organ, the pulvinus. Although a key determinant of pulvinus development, PETIOLULE-LIKE PULVINUS (PLP), has been identified, the molecular genetic basis for pulvinus function is largely unknown. Here, through an analysis of knockout mutants in barrelclover (Medicago truncatula), we showed that neither altering brassinosteroid (BR) content nor blocking BR signal perception affected pulvinus determination. However, BR homeostasis did influence nyctinastic leaf movement. BR activity in the pulvinus is regulated by a BR-inactivating gene PHYB ACTIVATION TAGGED SUPPRESSOR1 (BAS1), which is directly activated by PLP. A comparative analysis between M. truncatula and the non-pulvinus forming species Arabidopsis and tomato (Solanum lycopersicum) revealed that PLP may act as a factor that associates with unknown regulators in pulvinus determination in M. truncatula. Apart from exposing the involvement of BR in the functionality of the pulvinus, these results have provided insights into whether gene functions among species are general or specialized.
APA, Harvard, Vancouver, ISO, and other styles
3

Vázquez, M. D., C. Poschenrieder, and J. Barceló. "Pulvinus structure and leaf abscission in cadmium-treated bean plants (Phaseolus vulgaris)." Canadian Journal of Botany 67, no. 9 (September 1, 1989): 2756–64. http://dx.doi.org/10.1139/b89-355.

Full text
Abstract:
The effects of a phytotoxic cadmium concentration (4.45 × 10−5 M) on the structure of primary and secondary pulvini of bean (Phaseolus vulgaris L.) leaves were studied by light and scanning electron microscopy. Pulvini were also analysed for dry weight, water content, and cadmium, calcium and potassium concentrations. Relatively high amounts of Cd accumulated in the pulvini. The Cd treatment affected Ca more intensively than K concentrations, resulting in increased K/Ca molar ratios. Increase in the density of covering, glandular, and hydathode trichomes on the pulvini and internodes was observed in Cd-treated plants. Cadmium caused premature leaf abscission. Within both primary and secondary pulvini of unifoliolate and first trifoliolate leaves, Cd induced formation of a secondary abscission zone, which involved cortical cells parallel to the vascular cylinder. Cytological alterations associated with this zone were similar to those of normal plants in which the abscission zone lies at the pulvinus–petiole junction. Results suggest that Cd probably indirectly induces the conversion to cells with the competence of abscission zone cells in the cortex of pulvini.
APA, Harvard, Vancouver, ISO, and other styles
4

Szczepkowski, Andrzej, Błażej Gierczyk, and Anna Kujawa. "Buglossoporus pulvinus, a rare wood-inhabiting fungus on ancient oak trees in Poland: ecology, distribution and extinction risk assessment." BALTIC FORESTRY 25, no. 2 (December 31, 2019): 178–86. http://dx.doi.org/10.46490/vol25iss2pp178.

Full text
Abstract:
Buglossoporus pulvinus is widely distributed across Europe, within the range of Quercus robur. Throughout the area in which it appears, it is rare or very rare. It is listed as an endangered species in Europe and has been added to the Red Lists of fungi in a number of countries, along with awaiting inclusion in the IUCN Red List. In this study we have critically analysed the existing data about the occurrence of B. pulvinus in Poland. We have presented two new localities of the species in question in Poland, as well as new occurrences on the territory of the Białowieża National Park, the only place where this species had been previously recorded in Poland. Selected trees and logs inhabited by B. pulvinus have been characterized. We have indicated the number of observed basidiomata, their phenology, and the sizes of the largest specimens. We have identified 8 fungus species (Bisporella citrina, Daedalea quercina, Hapalopilus croceus, Hymenochaete rubiginosa, Laetiporus sulphureus, Mycena galericulata, M. inclinata, Xylobolus frustulatus) that coexist with B. pulvinus. Based on the new distribution data for B. pulvinus in Poland, according to IUCN Red List criteria this species should be classified as Endangered (EN).
APA, Harvard, Vancouver, ISO, and other styles
5

Virgona, JM, and EWR Barlow. "Drought Stress Induces Changes in the Non-Structural Carbohydrate Composition of Wheat Stems." Functional Plant Biology 18, no. 3 (1991): 239. http://dx.doi.org/10.1071/pp9910239.

Full text
Abstract:
The effect of drought stress on the non-structural carbohydrate (NSC) composition and water relations of the wheat (Triticum aestivum L.) stem has been investigated. Five separate parts of the stem were sampled: the unsheathed portion of the peduncle (Stem 1a), the sheathed portion of the peduncle (Stem 1b), the penultimate internode (Stem 2), the lower internodes (Stem 3+4) and the flag-leaf-pulvinus (pulvinus). The NSC was analysed as two fractions, an ethanol-soluble carbohydrate (ESC) fraction containing mono- and di-saccharides and some low molecular weight oligosaccharides, and a water-soluble carbohydrate (WSC) fraction containing mostly fructans and some high molecular weight oligosaccharides. In Stems 1b, 2 and 3 +4, the imposition of drought midway through grain filling resulted in a shift in soluble carbohydrate from the WSC to the ESC fraction indicating hydrolysis of fructans. In Stem 2 on day 29 of grain filling, the WSC/ESC ratio was 7.6 � 1.5 in well watered plants in contrast to 0.5 � 0.1 in droughted plants on day 30, even though NSC concentration did not differ. The NSC content of Stem la and the pulvinus increased threefold under drought, although levels were significantly lower than in the rest of the stem. The WSC/ESC ratio in these tissues was low com- pared to the rest of the stem but still declined noticeably under drought stress. Turgor (P) was fully maintained in Stem 2 and the pulvinus of droughted plants. Under drought, P in the pulvinus was maintained at higher levels (1.9-2.4 MPa) than in Stem 2 (0.8-1.2 MPa).
APA, Harvard, Vancouver, ISO, and other styles
6

Mayer, W. E., W. A. Rüge, N. Starrach, and R. Hampp. "Chloride Availability Affects the Malate Content and its Control by the Circadian Clock in Pulvini of Phaseolus coccineus L." Zeitschrift für Naturforschung C 42, no. 5 (May 1, 1987): 553–58. http://dx.doi.org/10.1515/znc-1987-0510.

Full text
Abstract:
Abstract In soil-grown 3-to 4-weeks-old Phaseolus coccineus L. plants the chloride content changed antagonistically in the extensor and flexor of the laminar pulvinus during the circadian leaf movement in continuous light. This is as expected for an osmoticum involved in the volume changes of pulvinar cells. H ow ever, the malate content of extensor and flexor cells was not altered in a circadian manner. Furthermore, during light/dark cycles the malate content in both, extensor and flexor, was higher in the light than in the dark. This indicates that malate was not used in the osmotic motor of leaf movement and that its level was not controlled by the circadian clock in 3-to 4-weeks-old soil-grown plants. When leaves were cut from 14-days-old soil-grown plants and cultured in distilled water the pulvini were depleted of chloride and the malate content was increased. In these chloride de­ prived leaves malate, and to a lesser extent citrate (about 1/10 of malate), changed antagonistically in a circadian manner in the extensor and flexor, indicating that these organic anions were now involved in the osmotic motor and under the control of the circadian clock. The similar properties of pulvinar and stomatal movements of starch-containing guard-cells are evident: in both cases, depending on the availability of chloride, CL- and/or organic anions are used for the compensation of the electrical charge of K+.
APA, Harvard, Vancouver, ISO, and other styles
7

Fisher, F. J. F., D. L. Ehret, and J. Hollingdale. "The pattern of vascular deployment near the pulvinus of the solar-tracking leaf of Lavatera cretica (Malvaceae)." Canadian Journal of Botany 65, no. 10 (October 1, 1987): 2109–17. http://dx.doi.org/10.1139/b87-290.

Full text
Abstract:
Distinguishable files of xylem and phloem elements that originate in first-order branches of the seven palmate major veins of Lavatera cretica leaves become separated from files unique to the radially aligned sections of the same veins before entering the pulvinus at the distal end of the petiole. The major veins initially merge to form a double coaxial tube: the outer cylinder comprises files unique to the major veins and the inner cylinder comprises files from lateral branches. Subsequent splitting, unfolding, and recombining of these cylinders results in the single narrow flexible tube constituting the hinge of the pulvinus. Proximal to this point, in L. cretica, the files reseparate into six alternately large and small petiolar bundles. The observed vascular pattern offers a means whereby signals from the lamina that elicit sun-tracking movements by the pulvinus can be integrated.
APA, Harvard, Vancouver, ISO, and other styles
8

Ismarrubie, Z. N., Han Lin Goh, S. Masuri, and Hanafiah Yussof. "Bio-Mechanism Response of Mimosa Pudica against External Stimulation." Advanced Materials Research 1125 (October 2015): 588–92. http://dx.doi.org/10.4028/www.scientific.net/amr.1125.588.

Full text
Abstract:
Mimosa Pudica (also known as Pokok Semalu) is an action plant with unique biological cell mechanism that has great potential to be explored for next generation biomechatronics devices. The motion principle of each petiole movement occurs by an organ of motion, called pulvinus. The behavior analysis of the Mimosa Pudica plant main pulvinus and petiole against external stimulations has been investigated. The response of the plant cell was observed by optical and scanning electron microscopes (SEM). External stimulation tests on Mimosa Pudica plant such as mechanical, electrical and light stimulations were conducted. Optical microscopy and SEM observations revealed the existence of red cells in the tertiary pulvinus. Mechanical stimulation results had shown a response time of approximately 2 seconds and a recovery time of 10 to 12 minutes for the leaves and 20 minutes for the petiole. Bending force of the petiole of Mimosa Pudica was also measured. The torque generated by the bending of petiole was found to increase exponentially as the pulvinus diameter increased. A torque of 30.91 g mm was generated from the bending of a petiole with 1.5 mm pulvinus diameter. The lifting potential of the Mimosa Pudica was tested using loadings with increments of 0.42 gram. The plant responded to electrical stimulation of 1.3 Ampere and displayed side effect. The light sensitivity region of Mimosa Pudica was obtained through light stimulation using a full spectrum daylight bulb, and ranges from 50 to 300 lux. Signal transmission to neighbouring structures was observed when the leaf was stimulated with threatening stimulus, with the signal speed achieving 0.8 cm/s. Movement mechanism of Mimosa Pudica is believed to be triggered by signal through receptor cells. It was found that the torque generated during petiole lifting is relatively higher than that during petiole bending.
APA, Harvard, Vancouver, ISO, and other styles
9

Lou, Yanhong, Liang Chen, Qingguo Xu, and Xunzhong Zhang. "Genotypic Variation of Morphological Traits in Tall Fescue (Festuca arundinacea Schreb.) Accessions." HortScience 50, no. 4 (April 2015): 512–16. http://dx.doi.org/10.21273/hortsci.50.4.512.

Full text
Abstract:
Tall fescue is an important cool-season grass widely used for forage and turf, and its genotypic variation for morphological traits has not been well documented. One hundred and fifteen tall fescue accessions, including 25 commercial cultivars, were divided into five groups based on their origination. The morphological traits, including plant height, spike length, pulvinus distance, spikelet count, branch count per spike, spike count per plant, and spike weight in different accessions were determined under field conditions in 2013 and 2014. There was significant genotypic variation in morphological traits among the 115 tall fescue accessions. Wild accessions exhibited a greater variation in the morphological traits than commercial cultivars. Close correlations were found among plant height, spike length, pulvinus distance, and spikelet count. The results of this suggest plant height, spike length, pulvinus distance, and spikelet count could be used as key morphological traits for evaluating all fescue germplasm effectively.
APA, Harvard, Vancouver, ISO, and other styles
10

Chen, Ming-Lin, Wen-Bin Mao, and Mei-Chen Cui. "Adaptive anatomical structure for nastic movement in Mimosa pudica L." Bangladesh Journal of Botany 42, no. 1 (July 28, 2013): 131–38. http://dx.doi.org/10.3329/bjb.v42i1.15876.

Full text
Abstract:
In order to study the adaptive anatomical structures during nastic movement of Mimosa pudica L., anatomical structures of main pulvinus, common petioles, rachis and leaflets were compared with Albizia julibrissin Durazz. (taken as control). The anatomical structures of main pulvinus and common petiole of M. pudica were different from that of A. julibrissin. Upon stimuliti, the protoplast volume of M. pudica in the lower cortical parenchyma cells become smaller than that in upper ones, a feature seldom found in A. julibrissin. There were found many reticulate lacunas on the two side of adaxial petiole of M. pudica, but nil in A. julibrissin. Similarly some ill developed lacunas were found in the pulvinus of rachis and leaflet of M. pudica, but absent in A. julibrissin. It appears that reticulate lacunas in common petiole of M. pudica are responsible for its strong nastic movement. The main sensitivity position lies at the base of common petiole, where the lower cortex is more sensitive than the upper cortex, and the ordinal sensitivity positions are rachis and leaflets. DOI: http://dx.doi.org/10.3329/bjb.v42i1.15876 Bangladesh J. Bot. 42(1): 131-137, 2013 (June)
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Pulvinus"

1

Pereira, Lorrayna Guedes. "A anatomia foliar poderia explicar a presença de espécies perenes nas florestas estacionais deciduais?" Universidade Federal de Uberlândia, 2012. https://repositorio.ufu.br/handle/123456789/13378.

Full text
Abstract:
Fundação de Amparo a Pesquisa do Estado de Minas Gerais
Although the majority of species in the deciduous forests lose their leaves during the dry season, some of them present alternative strategies, such as the leaf movement position (from horizontal to vertical ) in order to reduce transpiration. This study describes the leaf anatomy of nine plant species that reduce water loss during the dry season using the strategy of leaf movement rather than leaf abscission. The studied species were Piper aduncum sp. L. (Piperaceae), Acalypha Müll gracilis. Arg. (Euphorbiaceae), Casearia sylvestris Sw (Salicaceae), Bauhinia L. ungulata (Fabaceae: Caesalpinoideae) Calyptranthes widgreniana Berg. (Myrtaceae), Trichilia elegans A. Juss (Meliaceae) Guarea guidonia (L.) Sleumer (Meliaceae), Myrsine umbellata Mart. (Myrsinaceae) e Psychotria carthagenensis Jacq. (Rubiaceae), from the Parque Estadual do Pau Furado (Triângulo Mineiro), Brazil. Samples of the leaf blades and petioles were processed according to the usual techniques for plant anatomy. No general anatomical petiole pattern was found. However, some characteristics are common to all species: (a) supporting tissue, usually represented by collenchyma; (b) large cortical cells with thin walls and small intercellular spaces and (c) reduction or absence of lignified fibers. All these features could enhance the petiole flexibility allowing leaf changing position. The leaf blade anatomy revealed structural traits that promote water savings, as well as efficient mechanisms against predation by herbivores. These important features can effectively contribute to the maintenance and existence of these species in deciduous forests.
Embora a maioria das espécies ocorrentes nas florestas estacionais deciduais perca suas folhas durante a estação seca, algumas delas apresentam estratégias alternativas, tais como, a mudança no posicionamento das folhas de horizontal para vertical, para reduzir a transpiração. Este estudo descreve a anatomia foliar de nove dessas espécies de planta que reduzem a perda de água, durante a estação seca, usando a estratégia do movimento foliar e não a de apresentarem abscisão foliar. As espécies estudadas foram Piper aduncum sp. L. (Piperaceae), Acalypha gracilis Müll. Arg. (Euphorbiaceae), Casearia sylvestris Sw. (Salicaceae), Bauhinia ungulata L. (Fabaceae: Caesalpinoideae), Calyptranthes widgreniana Berg. (Myrtaceae), Trichilia elegans A. Juss (Meliaceae), Guarea guidonia (L.) Sleumer (Meliaceae), Myrsine umbellata Mart. (Myrsinaceae) e Psychotria carthagenensis Jacq. (Rubiaceae) do Parque Estadual do Pau Furado (Triângulo Mineiro). As amostras do limbo e do pecíolo foram processadas de acordo com as técnicas usuais para anatomia vegetal. Nenhum padrão anatômico geral foi encontrado para o pecíolo nas espécies analisadas. No entanto, foram observadas algumas características anatômicas comuns a todas elas, como: (a) tecido de sustentação, geralmente, representado pelo colênquima, (b) células corticais grandes, de paredes delgadas e com pequenos espaços intercelulares e (c) redução ou ausência de fibras lignificadas. Todas essas características poderiam garantir a flexibilidade ao pecíolo e assim, permitir a mudança de posição das folhas. A anatomia do limbo revelou características estruturais que favorecem a economia de água, além de mecanismos eficientes contra a herbivoria, características estas importantes e que poderiam contribuir efetivamente para a manutenção e existência dessas espécies nas florestas estacionais deciduais.
Mestre em Ecologia e Conservação de Recursos Naturais
APA, Harvard, Vancouver, ISO, and other styles
2

Rodrigues, Tatiane Maria [UNESP]. "Anatomia e aspectos ultra-estruturais de pulvinos de leguminosas de cerrado." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/88139.

Full text
Abstract:
Made available in DSpace on 2014-06-11T19:23:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-24Bitstream added on 2014-06-13T18:09:26Z : No. of bitstreams: 1 rodrigues_tm_me_botib.pdf: 1482984 bytes, checksum: 3e7256254b78e3c3d20bac0812d176a0 (MD5)
Os ajustes no posicionamento foliar em leguminosas, causados pelos pulvinos, representam um mecanismo eficiente que permite a maximização da fotossíntese em condições adversas. De um modo geral, os pulvinos de diferentes leguminosas apresentam um padrão estrutural que propicia grande flexibilidade a esta região da folha, incluindo córtex parenquimático desenvolvido com endoderme típica, sistema vascular central, reduzida lignificação de tecidos e extensiva conexão simplástica. Além disso, o conteúdo celular da endoderme parece determinar a velocidade do movimento foliar. Tradicionalmente, considera-se que a curvatura do pulvino é causada principalmente pela mudança de turgor das células corticais, as chamadas células motoras; entretanto, alguns estudos sugerem que o sistema vascular do pulvino também participa do seu funcionamento. Contudo, a maior parte das informações em literatura sobre anatomia e ultra-estrutura dos pulvinos refere-se a poucas espécies de leguminosas, sendo Mimosa pudica a mais estudada e caracterizada por movimentos foliares seismonásticos rápidos. Este trabalho descreve a estrutura do pulvino primário de nove espécies de leguminosas nativas de cerrado, com ênfase nas características celulares da endoderme e do sistema vascular, utilizando técnicas usuais em anatomia vegetal e microscopia eletrônica de transmissão. Foram selecionadas espécies com diferentes tipos e velocidades de movimento foliar: movimentos nictinástico e heliotrópico lentos (Bauhinia rufa, Copaifera langsdorffii, Senna rugosa - Caesalpinioideae; Andira humilis e Dalbergia miscolobium - Faboideae; Stryphnodendron polyphyllum - Mimosoideae), movimento heliotrópico lento (Zornia diphylla - Faboideae) e movimentos seismonástico rápido e nictinástico e heliotrópico lentos (Mimosa rixosa e Mimosa flexuosa...
Leaf position adjustment in leguminous species, occasioned by pulvini, represent an efficient mechanism that allows the photosynthesis maximization in adverse conditions. The pulvini of different leguminous species show a structural pattern that gives large flexibility to this leaf region, including developed parenchymatous cortex with typical endodermis, central vascular system, reduced tissue lignifications and extensive symplastic connections. Furthermore, the endodermis cell content seems to determine the leaf movement velocity. Traditionally, the pulvinus curvature is considered to be caused by turgor changes of the cortical cells, called motor cells; however, some studies suggest that the vascular system also participate in the pulvinus functioning. Nevertheless, the majority of literature information about pulvinus anatomy and ultrastructure refers to few leguminous species, being the most studied Mimosa pudica, specie characterized by fast seismonastic leaf movements. This work describes the primary pulvinus structure of nine leguminous species native from Brazilian cerrado, with emphasis on endodermis and vascular system cell features, using common vegetal anatomy and transmission electronic microscopy techniques. Species with different kinds and velocity of leaf movement were selected: slow nyctinastic and heliotropic movements (Bauhinia rufa, Copaifera langsdorffii, Senna rugosa - Caesalpinioideae; Andira humilis and Dalbergia miscolobium - Faboideae; Stryphnodendron polyphyllum - Mimosoideae), slow heliotropic movement (Zornia diphylla - Faboideae) and fast seismonastic and slow nyctinastic and heliotropic movements (Mimosa rixosa and Mimosa flexuosa - Mimosoideae). The pulvini of the studied species show a similar structural pattern, independent on the subfamily to that they belong and on the movement... (Complete abstract click electronic access below)
APA, Harvard, Vancouver, ISO, and other styles
3

Rodrigues, Tatiane Maria. "Anatomia e aspectos ultra-estruturais de pulvinos de leguminosas de cerrado /." Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/88139.

Full text
Abstract:
Orientador: Silvia Rodrigues Machado
Banca: Denise Maria Trombert de Oliveira
Banca: Élder Antonio Souza e Paiva
Resumo: Os ajustes no posicionamento foliar em leguminosas, causados pelos pulvinos, representam um mecanismo eficiente que permite a maximização da fotossíntese em condições adversas. De um modo geral, os pulvinos de diferentes leguminosas apresentam um padrão estrutural que propicia grande flexibilidade a esta região da folha, incluindo córtex parenquimático desenvolvido com endoderme típica, sistema vascular central, reduzida lignificação de tecidos e extensiva conexão simplástica. Além disso, o conteúdo celular da endoderme parece determinar a velocidade do movimento foliar. Tradicionalmente, considera-se que a curvatura do pulvino é causada principalmente pela mudança de turgor das células corticais, as chamadas células motoras; entretanto, alguns estudos sugerem que o sistema vascular do pulvino também participa do seu funcionamento. Contudo, a maior parte das informações em literatura sobre anatomia e ultra-estrutura dos pulvinos refere-se a poucas espécies de leguminosas, sendo Mimosa pudica a mais estudada e caracterizada por movimentos foliares seismonásticos rápidos. Este trabalho descreve a estrutura do pulvino primário de nove espécies de leguminosas nativas de cerrado, com ênfase nas características celulares da endoderme e do sistema vascular, utilizando técnicas usuais em anatomia vegetal e microscopia eletrônica de transmissão. Foram selecionadas espécies com diferentes tipos e velocidades de movimento foliar: movimentos nictinástico e heliotrópico lentos (Bauhinia rufa, Copaifera langsdorffii, Senna rugosa - Caesalpinioideae; Andira humilis e Dalbergia miscolobium - Faboideae; Stryphnodendron polyphyllum - Mimosoideae), movimento heliotrópico lento (Zornia diphylla - Faboideae) e movimentos seismonástico rápido e nictinástico e heliotrópico lentos (Mimosa rixosa e Mimosa flexuosa... (Resumo completo clicar acesso eletrônico abaixo)
Abstract: Leaf position adjustment in leguminous species, occasioned by pulvini, represent an efficient mechanism that allows the photosynthesis maximization in adverse conditions. The pulvini of different leguminous species show a structural pattern that gives large flexibility to this leaf region, including developed parenchymatous cortex with typical endodermis, central vascular system, reduced tissue lignifications and extensive symplastic connections. Furthermore, the endodermis cell content seems to determine the leaf movement velocity. Traditionally, the pulvinus curvature is considered to be caused by turgor changes of the cortical cells, called motor cells; however, some studies suggest that the vascular system also participate in the pulvinus functioning. Nevertheless, the majority of literature information about pulvinus anatomy and ultrastructure refers to few leguminous species, being the most studied Mimosa pudica, specie characterized by fast seismonastic leaf movements. This work describes the primary pulvinus structure of nine leguminous species native from Brazilian cerrado, with emphasis on endodermis and vascular system cell features, using common vegetal anatomy and transmission electronic microscopy techniques. Species with different kinds and velocity of leaf movement were selected: slow nyctinastic and heliotropic movements (Bauhinia rufa, Copaifera langsdorffii, Senna rugosa - Caesalpinioideae; Andira humilis and Dalbergia miscolobium - Faboideae; Stryphnodendron polyphyllum - Mimosoideae), slow heliotropic movement (Zornia diphylla - Faboideae) and fast seismonastic and slow nyctinastic and heliotropic movements (Mimosa rixosa and Mimosa flexuosa - Mimosoideae). The pulvini of the studied species show a similar structural pattern, independent on the subfamily to that they belong and on the movement... (Complete abstract click electronic access below)
Mestre
APA, Harvard, Vancouver, ISO, and other styles
4

O'Brien, Brendan John. "The architecture, connectivity and organization of Macaca inferior pulvinar /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/10655.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Irving, Michael. "Reversible plant movement studied at single cell resolution." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321434.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Saeedi, Saed. "Observations chez cassia fasciculata et mimosa pudica d'effets induits sur la physiologie des pulvini par des composes phenoliques et benzoiques et etude des modalites de l'absorption de l'acide salicylique." Poitiers, 1987. http://www.theses.fr/1987POIT2269.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Maior, Rafael Plakoudi Souto. "Avaliação da via colículo-pulvinar no processamento das emoções e cognição social em primatas não-humanos." reponame:Repositório Institucional da UnB, 2011. http://repositorio.unb.br/handle/10482/9861.

Full text
Abstract:
Tese (doutorado)—Universidade de Brasília, Faculdade de Ciências da Saúde, 2011.
Submitted by Albânia Cézar de Melo (albania@bce.unb.br) on 2012-01-13T13:54:29Z No. of bitstreams: 1 2011_RafaelPlakoudiSoutoMaior.pdf: 21698392 bytes, checksum: 20d3c5fb58d88ae54b47ae9f945f6f49 (MD5)
Approved for entry into archive by Patrícia Nunes da Silva(patricia@bce.unb.br) on 2012-01-18T19:18:23Z (GMT) No. of bitstreams: 1 2011_RafaelPlakoudiSoutoMaior.pdf: 21698392 bytes, checksum: 20d3c5fb58d88ae54b47ae9f945f6f49 (MD5)
Made available in DSpace on 2012-01-18T19:18:23Z (GMT). No. of bitstreams: 1 2011_RafaelPlakoudiSoutoMaior.pdf: 21698392 bytes, checksum: 20d3c5fb58d88ae54b47ae9f945f6f49 (MD5)
Mecanismos de defesa em primatas dependem do reconhecimento rápido de potenciais predadores e pistas sociais de coespecíficos como expressões faciais de emoção. O complexo amigdaloide (AM) é considerado o centro da circuitaria neural responsável pela detecção de ameaça. Apesar de ser essencial no processamento de estímulos emocionais, a AM parece não estar envolvida nas primeiras etapas deste processo. Várias linhas de investigação vêm recentemente indicando que a via colículo-pulvinar pode preencher essa lacuna, especialmente durante a infância. Para avaliar a contribuição de ambas estruturas (colículo superior e pulvinar) no processamento de estímulos relevantes para sobrevivência, o presente trabalho divide-se em dois estudos. No primeiro estudo, a atividade elétrica individual de neurônios do pulvinar foi registrada durante o reconhecimento de faces emocionais em uma tarefa de escolha diferente do modelo. Nesta tarefa, foram utilizadas faces com diferentes expressões emocionais (tristeza, raiva, alegre, surpresa e neutra), além de figuras geométricas simples como controle de estímulo. De um total de 184 neurônios registrados das regiões lateral e medial do pulvinar de dois macacos japoneses (Macaca fuscata), 22% respondiam a estímulos visuais. Os resultados indicam que 43,9% destes “neurônios visuais” responderam diferencialmente a expressões emocionais de faces. A latência das respostas neuronais no pulvinar variou largamente: o início de disparos para 16 neurônios (39,0%) ocorreu antes de 100 ms, ao passo que, para 13 neurônios (31,7%), ocorreu depois de 300 ms. Essa distribuição variada de latências sugere que os neurônios do pulvinar intermediam conexões intracorticais assim como uma via subcortical mais rápida para a AM. No segundo estudo, filhotes de macaco-prego (Cebus spp.) foram submetidos à lesão neurotóxica bilateral do colículo superior. O comportamento social deles foi avaliado no próprio viveiro (comportamento espontâneo), assim como em dois testes sociais: dominância social e interação com adultos estranhos. Eles também foram testados em um paradigma de conflito ameaça-recompensa em que uma recompensa (comida) foi apresentada junto com um estímulo de ameaça (modelo de serpente de borracha). Os resultados dos testes comportamentais sugerem que a lesão no colículo superior não altera os níveis de interação social. Entretanto os animais lesados mostraram uma clara desinibição comportamental em relação a serpente. Falta de inibição nesta tarefa foi observada até um ano após o primeiro teste. Esse duradouro déficit de reconhecimento de um predador natural é similar ao aspecto de docilidade da Síndrome de Klüver-Bucy e indica um papel importante do colículo superior no reconhecimento de ameaças. Em conjunto, os resultados dos dois estudos sugerem que a via colículo-pulvinar exerce um papel importante no processamento de estímulos relevantes para a sobrevivência, sejam pistas sociais e/ou estímulos de ameaça. ______________________________________________________________________________ ABSTRACT
Defense mechanisms in primates rely on the fast recognition of potential predators and social cues of conspecifics such as facial expressions of emotions. The neural circuitry responsible for the detection of threat is generally thought to be centered on the amygdala. Although it is a pivotal structure in the processing of emotional stimuli, the amygdala does not seem necessary for the early stages of this process. Converging findings from several lines of investigation have been pointing to the colliculo-pulvinar pathway as a possible candidate to fill in this gap, especially during infancy. To evaluate the contribution of both structures (superior colliculus and pulvinar) to the processing of survival-relevant stimuli, the present work is divided into two studies. In the first study, we recorded single-unit activity of pulvinar neurons in two japanese monkeys (Macaca fuscata) during recognition of emotional faces in a delayed non-match-to-sample (DNMS) task, using human face stimuli with differing emotional expressions (sad, angry, happy, surprised and neutral) and simple geometric pattern control figures. From a total of 184 single neurons sampled from lateral and medial pulvinar, 22% were “visually responsive”. The results thus indicate that 43.9% of the visually responsive pulvinar neurons differentially responded to the emotional expressions of human faces. Response latencies of the pulvinar neurons to these facial stimuli ranged very widely; firing onsets for 16 (39.0%, 16/41) neurons were shorter than 100 ms, while for 13 (31.7%, 13/41) it was greater than 300 ms. This wide distribution of response latencies in pulvinar neurons suggests that pulvinar neurons might mediate intracortical connections as well as the fast subcortical pathway to the amygdala. In the second study, infant capuchin monkeys (Cebus spp.) were submitted to bilateral neurotoxic lesion of the superior colliculus. Their social behavior was analyzed in their home cage (spontaneous behavior) as well as in two social tests: social dominance and interaction with strange adults. They were also tested in a threat-reward conflict test where food reward was presented with a threatening stimulus (rubber snake). Results from social behavioral tests suggest that superior colliculus lesion does not affect spontaneous social interaction. Nevertheless, lesioned monkeys were uninhibited by a snake in a food-reward retrieval task. Lack of inhibition in the task was observed over the course of one year. The long lasting recognition impairment of a natural predator observed here is similar to the tameness aspects of Klüver–Bucy syndrome, indicating an important role of this structure in threat recognition. Taken together, results from both studies indicate that the colliculo-pulvinar pathway plays an important role in the processing of survival-relevant stimuli, either social cues and/or threatening stimuli.
APA, Harvard, Vancouver, ISO, and other styles
8

Cortés, Hernández Nelson. "Le rôle du noyau Pulvinar du thalamus dans la transmission de l'activité visuelle à travers le cortex." Paris 6, 2012. http://www.theses.fr/2012PA066375.

Full text
Abstract:
Seules les voies cortico-corticales sont prises en compte d'habitude dans le flux d'informations à travers le cortex visuel. Cependant, les expériences et la théorie ont montré que ce mode de transmission posait de nombreux problèmes. Dans cette thèse, j'explore le rôle d'une voie alternative du flux d'information. La hiérarchie corticale visuelle est connecté au noyau Pulvinar du thalamus et cela fournit une seconde voie qui peut lier l'activité des différentes aires corticales. Le Pulvinar a des connexions longue portée qui lui confèrent un rôle de couplage global, conduisant à un raccourci efficace entre les aires corticales. Le but principal de ce travail est de montrer que cela permet une transmission quasi linéaire de l'entrée visuelle tout au long du cortex visuel. Deux modèles théoriques ont été implémentés pour analyser comment le Pulvinar améliore la transmission corticale. Le premier modèle est un réseau de neurones décrits par leur fréquence de décharge. Dans le second modèle, constitué de neurones << intègre-et-décharge >>, l'activité neuronale est décrite par des potentiels d'action. Les résultats de nos simulations montrent que les connexions cortico-corticales déterminent les champs récepteurs visuels à travers les niveaux hiérarchiques, le Pulvinar contrôle le gain de la propagation. De plus, alors que les connexions cortico-corticales sont responsables de la décorrélation du signal transmis à travers le cortex, les bouffées d'activité synchronisées du Pulvinar peuvent << réveiller >> le cortex.
APA, Harvard, Vancouver, ISO, and other styles
9

Schneider, Lukas [Verfasser], Igor [Akademischer Betreuer] Kagan, Igor [Gutachter] Kagan, and Melanie [Gutachter] Wilke. "Perceptual and motor intentional processing in dorsal pulvinar / Lukas Schneider ; Gutachter: Igor Kagan, Melanie Wilke ; Betreuer: Igor Kagan." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1189419653/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Griep, Hendrik [Verfasser], and Jens-Max [Gutachter] Hopf. "Die Rolle des Pulvinars bei der Verarbeitung von Distraktoren und visueller Suche / Hendrik Griep ; Gutachter: Jens-Max Hopf." Magdeburg : Universitätsbibliothek Otto-von-Guericke-Universität, 2020. http://d-nb.info/1226932053/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Pulvinus"

1

Walter, Daniel. Pulvis et umbra sumus. [United States: W. Daniel], 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Ásgeirsson, Jón Ma, ed. Pulvis Olympicus: Afmælisrit tileinkað Sigurði Péturssyni. Reykjavík: Háskólaútgáfan, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Pulvis es ...: Ricordi e riflessioni di un comunista. Venezia: Marsilio, 2011.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Gattass, Ricardo, Juliana G. M. Soares, and Bruss Lima. The Pulvinar Thalamic Nucleus of Non-Human Primates: Architectonic and Functional Subdivisions. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-70046-5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

The Pulvinus: Motor Organ for Leaf Movement (Current Topics in Plant Physiology : An American Society of Plant Physiologists Ser. ; Vol. III). American Society of Plant Physiologists, 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Pulvis et umbra. 2017.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Gattass, Ricardo, Juliana G. M. Soares, and Bruss Lima. The Pulvinar Thalamic Nucleus of Non-Human Primates: Architectonic and Functional Subdivisions. Springer, 2017.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Saalmann, Yuri B., and Sabine Kastner. Neural Mechanisms of Spatial Attention in the Visual Thalamus. Edited by Anna C. (Kia) Nobre and Sabine Kastner. Oxford University Press, 2014. http://dx.doi.org/10.1093/oxfordhb/9780199675111.013.013.

Full text
Abstract:
Neural mechanisms of selective attention route behaviourally relevant information through brain networks for detailed processing. These attention mechanisms are classically viewed as being solely implemented in the cortex, relegating the thalamus to a passive relay of sensory information. However, this passive view of the thalamus is being revised in light of recent studies supporting an important role for the thalamus in selective attention. Evidence suggests that the first-order thalamic nucleus, the lateral geniculate nucleus, regulates the visual information transmitted from the retina to visual cortex, while the higher-order thalamic nucleus, the pulvinar, regulates information transmission between visual cortical areas, according to attentional demands. This chapter discusses how modulation of thalamic responses, switching the response mode of thalamic neurons, and changes in neural synchrony across thalamo-cortical networks contribute to selective attention.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Pulvinus"

1

Correia, Stephen. "Pulvinar." In Encyclopedia of Clinical Neuropsychology, 2895–900. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-57111-9_1390.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Correia, Stephen. "Pulvinar." In Encyclopedia of Clinical Neuropsychology, 2082–86. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-0-387-79948-3_1390.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Mehlhorn, Heinz. "Pulvillus." In Encyclopedia of Parasitology, 2290. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-43978-4_2601.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Correia, Stephen. "Pulvinar." In Encyclopedia of Clinical Neuropsychology, 1–6. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-56782-2_1390-2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Mehlhorn, Heinz. "Pulvillus." In Encyclopedia of Parasitology, 1–2. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-642-27769-6_2601-2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Azimova, Shakhnoza S., and Anna I. Glushenkova. "Thymus pulvinatus." In Lipids, Lipophilic Components and Essential Oils from Plant Sources, 541. London: Springer London, 2012. http://dx.doi.org/10.1007/978-0-85729-323-7_1727.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Frank, J. Howard, J. Howard Frank, Michael C. Thomas, Allan A. Yousten, F. William Howard, Robin M. Giblin-davis, John B. Heppner, et al. "Pulvillus (pl., pulvilli)." In Encyclopedia of Entomology, 3073. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6359-6_3244.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Gattass, Ricardo, Juliana G. M. Soares, and Bruss Lima. "Chemoarchitecture of the Pulvinar." In The Pulvinar Thalamic Nucleus of Non-Human Primates: Architectonic and Functional Subdivisions, 9–14. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-70046-5_3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Gattass, Ricardo, Juliana G. M. Soares, and Bruss Lima. "Connectivity of the Pulvinar." In The Pulvinar Thalamic Nucleus of Non-Human Primates: Architectonic and Functional Subdivisions, 19–29. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-70046-5_5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Ramón y Cajal, Santiago. "Lateral Geniculate Body and Pulvinar." In Texture of the Nervous System of Man and the Vertebrates, 49–60. Vienna: Springer Vienna, 2002. http://dx.doi.org/10.1007/978-3-7091-6730-4_3.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Pulvinus"

1

Basir, Siti Nora, Hanafiah Yussof, Nur Ismarrubie Zahari, and Fahrulrodzi Idris. "Design concept of a new bio-inspired tactile sensor based on main pulvinus motor organ cells distribution of Mimosa Pudica plant." In 2014 International Symposium on Micro-NanoMechatronics and Human Science (MHS). IEEE, 2014. http://dx.doi.org/10.1109/mhs.2014.7006091.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Chakravorti, Srijata, Victoria L. Morgan, Paula Trujillo Diaz, Raul Wirz Gonzalez, and Benoit M. Dawant. "A structural connectivity approach to validate a model-based technique for the segmentation of the pulvinar complex." In Biomedical Applications in Molecular, Structural, and Functional Imaging, edited by Barjor Gimi and Andrzej Krol. SPIE, 2018. http://dx.doi.org/10.1117/12.2293685.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Pulvinus' for particular source types:
Journal articles Dissertations / Theses
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography