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Journal articles on the topic "Pedicels"
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Athoo, Thomas O., Andreas Winkler, and Moritz Knoche. "Pedicel Transpiration in Sweet Cherry Fruit: Mechanisms, Pathways, and Factors." Journal of the American Society for Horticultural Science 140, no. 2 (March 2015): 136–43. http://dx.doi.org/10.21273/jashs.140.2.136.
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Pedicel appearance is a good indicator of freshness in sweet cherries (Prunus avium L.). Fruit with shriveled, discolored pedicels have reduced market value. Shriveled pedicels are thought to result from postharvest water loss due to transpiration. The objectives of our study were to 1) quantify the transpiration permeances of fruit and pedicel surfaces; 2) determine the role of the fruit in pedicel transpiration; and 3) identify the effects of selected factors on pedicel transpiration. Fruit with and without pedicels were incubated under controlled conditions [usually 22 °C, 75% relative humidity (RH)] and their mass losses determined gravimetrically. Pedicel transpiration was calculated by subtracting measured transpiration of fruit without pedicels from that of fruit with pedicels. Cumulative pedicel transpiration increased with time. Rates of pedicel transpiration were essentially constant over the first 0 to 1.5 hours but declined thereafter, approaching an asymptote over the subsequent period of 1.5 to 96 hours over which measurements were made. Cumulative pedicel transpiration exceeded the amount of water in the pedicel, indicating that at least some of the transpired water originated from the fruit. There was no significant effect of steam girdling on pedicel transpiration suggesting that water moved from the fruit to the pedicel through the xylem (steaming prevents phloem conduction). Abrading the cuticular membrane (CM) from a pedicel surface or extracting the cuticular wax by dipping pedicels once or five times in chloroform/methanol (1:1 v/v) increased rates of transpiration 12-, 3-, and 5-fold, respectively. The water vapor permeance of the pedicel surface determined under steady-state conditions (8.7 ± 0.4 × 10−4 m·s−1) exceeded that of the fruit (2.1 ± 0.1 × 10−4 m·s−1), possibly because of a more permeable CM and/or a higher stomatal density (38.5 ± 1.3 stomata/mm2 for pedicels vs. 1.1 ± 0.0 stomata/mm2 for fruit). Treatments known to affect stomatal opening (incubation in buffered abscisic acid at 0.1 mm or in CO2- or N2-atmospheres) had no effects on pedicel transpiration. Rates of transpiration were negatively correlated with RH but positively with temperature. There was no effect of RH and/or temperature on the permeances of pedicel or fruit surfaces. From our results it is inferred that 1) pedicel transpiration is a physical process governed by Fick’s law of diffusion, where cuticle and wax in particular represent the major rate-limiting barriers; 2) the permeances of pedicel surfaces exceed those of fruit surfaces; and 3) pedicel transpiration can be minimized by minimizing the driving force (difference in water vapor concentration) during postharvest handling and storage.
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Kardolus, J. P., and N. Bezem. "The floral abscission zone in series Acaulia and related taxa of Solanum section Petota." Canadian Journal of Botany 76, no. 8 (August 1, 1998): 1424–32. http://dx.doi.org/10.1139/b98-149.
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Species of the genus Solanum usually possess pedicels with a floral abscission zone, which is designated the "articulation" or "joint." A distinct group of tuber-bearing wild potatoes, series Acaulia, is characterized by an indistinct or completely absent articulation. The anatomy of pedicels without articulation is compared with that of articulated pedicels. No abscission zone is observed in pedicels without an articulation, a situation found in the tetraploids Solanum acaule Bitter ssp. acaule and S. acaule ssp. punae (Juz.) Hawkes & Hjert. The hexaploids Solanum albicans (Ochoa) Ochoa and S. acaule ssp. palmirense Kardolus of series Acaulia have an anatomically incompletely differentiated abscission zone. Solanum acaule ssp. aemulans (Bitter & Wittm.) Hawkes & Hjert. (2n = 48) has articulated pedicels and a floral abscission zone. The absence of a floral abscission zone is presumably a recessive trait. The special features of pedicel articulation in series Acaulia are discussed in relation to the "jointless" mutations in tomato. The position of the articulation on the pedicel is concluded to be less significant for taxonomy than generally considered.Key words: Solanaceae, Solanum acaule, anatomy, "jointless" mutation, pedicel articulation, taxonomy.
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LoPresti, E. F., J. Goidell, J. M. Mola, M. L. Page, C. D. Specht, C. Stuligross, M. G. Weber, N. M. Williams, and R. Karban. "A lever action hypothesis for pendulous hummingbird flowers: experimental evidence from a columbine." Annals of Botany 125, no. 1 (August 12, 2019): 59–65. http://dx.doi.org/10.1093/aob/mcz134.
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Abstract Background and Aims Pendulous flowers (due to a flexible pedicel) are a common, convergent trait of hummingbird-pollinated flowers. However, the role of flexible pedicels remains uncertain despite several functional hypotheses. Here we present and test the ‘lever action hypothesis’: flexible pedicels allow pendulous flowers to move upwards from all sides, pushing the stigma and anthers against the underside of the feeding hummingbird regardless of which nectary is being visited. Methods To test whether this lever action increased pollination success, we wired emasculated flowers of serpentine columbine, Aquilegia eximia, to prevent levering and compared pollination success of immobilized flowers with emasculated unwired and wire controls. Key Results Seed set was significantly lower in wire-immobilized flowers than unwired control and wire control flowers. Video analysis of visits to wire-immobilized and unwired flowers demonstrated that birds contacted the stigmas and anthers of immobilized flowers less often than those of flowers with flexible pedicels. Conclusions We conclude that flexible pedicels permit the levering of reproductive structures onto a hovering bird. Hummingbirds, as uniquely large, hovering pollinators, differ from flies or bees which are too small to cause levering of flowers while hovering. Thus, flexible pedicels may be an adaptation to hummingbird pollination, in particular due to hummingbird size. We further speculate that this mechanism is effective only in radially symmetric flowers; in contrast, zygomorphic hummingbird-pollinated flowers are usually more or less horizontally oriented rather than having pendulous flowers and flexible pedicels.
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Carbonaro, Della, and William B. Miller. "ELONGATION OF LILIUM LONGIFLORUM BUDS AND PEDICELS IS LOCALIZED AT THE BUD BASE REGION." HortScience 25, no. 9 (September 1990): 1063b—1063. http://dx.doi.org/10.21273/hortsci.25.9.1063b.
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Success in the production of seasonal flowering plants requires adequate knowledge of plant growth patterns and rates. In Easter lilies, pedicel growth is one the components of final plant height. Flower bud growth rates are important from the standpoint of timing of anthesis. To learn more about the localization of growth in Easter lily flower buds and pedicels, we conducted a time course experiment. Buds and pedicels were marked at 1.2 mm intervals using an inked bolt. Distances between ink marks were determined at 3 day intervals. Results indicate that 30 mm flower buds elongate almost exclusively from basal regions of the bud. The basal 1.2 mm segment elongated 16 mm in 20 days, while the apical 1.2 mm segment elongated 0.75 mm in the same period. Larger buds (initially 90 mm) gave similar results, although bud tip growth rate increased to some degree just prior to flowering. Pedicel elongation occurred almost exclusively at the apical end of the pedicel, adjacent to the region of greatest bud growth.
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Lautenschläger, Thea, Markus Rüggeberg, Niclas Noack, Katharina Bunk, Monizi Mawunu, Thomas Speck, and Christoph Neinhuis. "Functional principles of baobab fruit pedicels – anatomy and biomechanics." Annals of Botany 126, no. 7 (August 18, 2020): 1215–23. http://dx.doi.org/10.1093/aob/mcaa149.
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Abstract Background and Aims Fruit pedicels have to deal with increasing loads after pollination due to continuous growth of the fruits. Thus, they represent interesting tissues from a mechanical as well as a developmental point of view. However, only a few studies exist on fruit pedicels. In this study, we unravel the anatomy and structural–mechanical relationships of the pedicel of Adansonia digitata, reaching up to 90 cm in length. Methods Morphological and anatomical analyses included examination of stained cross-sections from various positions along the stalk as well as X-ray microtomography and scanning electron microscopy. For mechanical testing, fibre bundles derived from the mature pedicels were examined via tension tests. For establishing the structural–mechanical relationships, the density of the fibre bundles as well as their cellulose microfibril distribution and chemical composition were analysed. Key Results While in the peduncle the vascular tissue and the fibres are arranged in a concentric ring-like way, this organization shifts to the polystelic structure of separate fibre bundles in the pedicel. The polystelic pedicel possesses five vascular strands that consist of strong bast fibre bundles. The fibre bundles have a Young’s modulus of up to 5 GPa, a tensile strength of up to 400 MPa, a high density (>1 g cm−3) and a high microfibril angle of around 20°. Conclusions The structural arrangement as well as the combination of high density and high microfibril angle of the bast fibre bundles are probably optimized for bearing considerable strain in torsion and bending while at the same time allowing for carrying high-tension loads.
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Habdas, Hanna, Leszek S. Jankiewicz, and Bożena Borkowska. "Changes in anatomical structure of apple fruitlet pedicels preceding June drop." Acta Agrobotanica 35, no. 1 (2013): 11–23. http://dx.doi.org/10.5586/aa.1982.002.
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The anatomical structure of pedicels of apple fruitlets was investigated. The fruitlets of cv. 'Mcintosh' and 'Bancroft' were collected on June 8th, 16th an 24th. The middle date coincided with the beginning of June drop. The pedicel structure of larger fruitlets which tended to be retained on the tree was compared with that of smaller fruitlets which tended to be shed of. In the pedicels of larger fruitlets, development of the xylem, especially secondary one, was more intensive. This difference increased in time. Lignification of cortex sclereids, phloem fibers, xylem parenchyma cells and pith cells was also more advanced. The differences in the amount of phloem tissue between both kinds of fruitlets were not large but usually significant. The mentioned differences especially in pedicel xylem development are considered to be partly responsible for the fact that smaller fruitlets loose gradually their ability to compete for nutrients. This finally leads to their starvation and shedding.
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Pérez, Francisco J., and Verónica Morales. "A basic peroxidase isoenzyme from the grape pedicel is induced by gibberellic acid." Functional Plant Biology 26, no. 4 (1999): 387. http://dx.doi.org/10.1071/pp98127.
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Soluble peroxidase activity from pedicels of seedless table grape cv. Sultana was highly stimulated by post-bloom applications of gibberellic acid (GA3) to vines. The increase in peroxidase activity was mainly due to the induction of a basic peroxidase isoenzyme (pI > 9; BPrx-HpI). The activity of two other peroxidase isoenzymes of pI 6.5 and 3.2 was not altered by the hormone treatment. BPrx-HpI was induced by GA3 in pedicels and rachis but not in berries, although in berries peroxidase activity was also stimulated by post-bloom GA3 applications. BPrx-HpI oxidised guaiacol and ortho-phenylenediamine (o-PDA), while the others peroxidases found in the pedicel and in the berry oxidised only o-PDA. Hence, BPrx-HpI was characterised as a guaiacol-peroxidase showing no activity towards ascorbic acid (ASC). The possible role of BPrx-HpI in pedicel lignification and berry-drop caused by GA3 applications to cv. Sultana vines is discussed.
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GOUVÊA, YURI FERNANDES, and JOÃO RENATO STEHMANN. "Two new species of the Solanum asterophorum species group (Solanum subg. Leptostemonum, Solanaceae) from the Brazilian Atlantic Forest." Phytotaxa 288, no. 2 (December 14, 2016): 120. http://dx.doi.org/10.11646/phytotaxa.288.2.2.
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Two new species of “spiny” Solanum (subgenus Leptostemonum), endemic to the Atlantic Forest of the southeastern region of Brazil, are described. Solanum igniferum and Solanum sessilantherum are morphologically related to Solanum asterophorum. Solanum igniferum inhabits the southern region of Espírito Santo State, and can be primarily distinguished from S. asterophorum by its orange-colored to ferruginous vestiture and the pedicels that are straight, or nearly so, keeping the flower buds erect to patent. Solanum sessilantherum differs chiefly from S. asterophorum also by pedicels that are straight, or nearly so, keeping the floral buds erect to patent, loosely arranged inflorescences, with armed axis, usually with unpaired pedicel insertion points when fully developed, and inconspicuous filaments giving the anthers a sessile appearance. Full descriptions, illustrations, distribution map and conservation status are provided, as well as comparative notes on the morphology, geography and some ecological aspects.
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Tarnowski, Tara L., José M. Pérez-Martínez, and Randy C. Ploetz. "Fuzzy Pedicel: A New Postharvest Disease of Banana." Plant Disease 94, no. 5 (May 2010): 621–27. http://dx.doi.org/10.1094/pdis-94-5-0621.
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Banana fruit of the Cavendish subgroup, Musa acuminata, are significant international commodities. Recently, a transnational company attempted to develop single fruit (fingers) as a product in the United States. In the summer of 2007, an unknown problem developed (hereafter, “fuzzy pedicel”), wherein mats of fluffy gray to white mycelial mats covered large portions of the pedicel surface of fruit when they were packed in gas-permeable containers. Fungi from two genera sporulated on examined pedicels: Sporothrix, which occurred on 72% of the affected pedicels, and Fusarium (6%); other fungi were sterile. From pedicel tissue, four genera of fungi were isolated on potato dextrose agar: Sporothrix and Fusarium and, less frequently, Pestalotiopsis and Nigrospora. Based on alignment with internal transcribed spacer and β-tubulin sequence data, the Sporothrix isolates were closely related to those in an environmental Ophiostoma/Sporothrix clade that contains Sporothrix stylites, S. humicola, and S. pallida but not the human pathogen S. schenkii. Based on EF1α gene sequences, four species in the Gibberella fujikuroi species complex (Fusarium proliferatum, F. pseudocircinatum, F. sacchari, and F. verticillioides) and two unnamed taxa in the F. incarnatum-equiseti species complex were identified. After artificial inoculation, representative Sporothrix and Fusarium isolates caused fuzzy pedicel symptoms on fruit of ‘Grand Nain,’ a commercial Cavendish cultivar. Fuzzy pedicel development was inhibited at 14°C (temperature at which fruit are shipped) but developed at 25°C (temperature at which fruit are marketed). Sporothrix isolates were insensitive to thiophanate-methyl fungicide in vitro and when used to treat pedicel surfaces prior to inoculation. Thus, it appears that benzimidazole fungicides would be ineffective as postharvest treatments for this problem. In summary, a new postharvest disease of banana, fuzzy pedicel, affects single fingers. It is caused by Sporothrix sp. and several species of Fusarium. Sporothrix spp. and F. pseudocircinatum have not been reported previously on banana.
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HOQUE, AKRAMUL, PAKSHIRAJAN LAKSHMINARASIMHAN, and DEBABRATA MAITY. "Dioscorea longipedicellata (Dioscoreaceae), a new species from the Indian subcontinent." Phytotaxa 367, no. 2 (September 4, 2018): 173. http://dx.doi.org/10.11646/phytotaxa.367.2.7.
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A new species of Dioscorea, viz., D. longipedicellata is described and illustrated based on collections from northeast India and northwest Bangladesh. The new species is closely allied to D. kamoonensis and D. pentaphylla. D. longipedicellata can be diagnosed by its glabrous stem, glabrous membranous lamina, pedicellate male flowers, funnel-shaped, fleshy prominent pedicels, glabrous bract situated at the base of pedicel directly on rachis and membranous, glabrous tepals.
Dissertations / Theses on the topic "Pedicels"
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Rodrigues, Marciene Amorim. "Estudos moleculares, anat?micos e express?o g?nica de gen?tipos de bananeira contrastantes quanto ao despencamento dos frutos." Universidade Estadual de Feira de Santana, 2015. http://localhost:8080/tede/handle/tede/236.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The finger drop of banana is closely related to the maturation process and involves the softening and weakening of the pedicel. The aim of this study was to evaluate the genetic diversity of banana genotypes with contrasting levels of fruit finger drop by means of molecular markers and evaluate the susceptibility and resistance to finger drop from anatomical studies and analysis of gene expression via real-time quantitative PCR.The genotyping data generated by microsatellites was carried out based on the number of base pairs of each fragment and dendrogram cluster calculated by UPGMA method. Of the 30 microsatellite primer evaluated, 139 alleles were obtained, with the average of 4.66 alleles per locus. No relationship was found between the polymorphism detected by microsatellite markers and the degree of finger drop fruit. For the anatomical characterization, genotypes in the maturation stages 4, 5 and 6, and from different ploidy levels and finger drop resistance patterns, were used. In genotype 017041-01, susceptible, the presence of air parenchyma, was observed, a feature which was not evidenced in the resistant genotypes genotypes BB France, Khai Nai and BRS On Preciosa. Higher values of variable AF and increased deposition of lignin in the vascular bundles, were related to finger drop resistance. The values of Ct (cycle threshold) were used to determine the gene expression difference on cell wall modifier genes (PEL1, EXP1 and XTH4) between different stages of maturation in the finger drop zone (ZD) and in the middle of the fruit (control zone-ZC). To perform the analysis of relative expression, the 2? ?? CT method, was used. RT-qPCR analysis showed that there was a differential expression between the stages of maturation. Ploidy levels and resistance patterns, did not show correlation with the results of the expression. Genes XTH4 and PEL1 showed expression profiles related to finger drop in fruits in different genotypes being good candidates for functional studies in bananas, and may be useful in strategies of genetic improvement aiming the production of banana fruits with resistance to finger drop.
O despencamento natural dos frutos da bananeira est? estreitamente relacionado com o processo de matura??o e envolve o amolecimento e enfraquecimento do pedicelo. O objetivo deste trabalho foi estudar a diversidade gen?tica de gen?tipos de bananeira com n?veis contrastantes ao despencamento dos frutos por meio de marcadores moleculares e avaliar a suscetibilidade e resist?ncia ao despencamento a partir de estudos anat?micos e an?lise de express?o g?nica via PCR quantitativo em tempo real. A genotipagem dos dados gerados pelos microssat?lites foi realizada com base no n?mero de pares de base de cada fragmento e para o agrupamento no dendrograma, utilizou-se o m?todo UPGMA. Dos 30 iniciadores microssat?lites avaliados, obteve-se 139 alelos, com m?dia de 4,66 alelos por loco. N?o foi observada rela??o entre o polimorfismo detectado pelos marcadores microssat?lites e o grau de despencamento dos frutos Para a caracteriza??o anat?mica, foram utilizados gen?tipos nos est?dios de matura??o 4, 5 e 6, de diferentes ploidias e padr?es de resist?ncia ao despencamento. No gen?tipo suscet?vel 017041-01 foi observada presen?a marcante de par?nquima aer?fero, caracter?stica que n?o foi evidenciada nos gen?tipos resistentes BB Fran?a, Khai Nai On e BRS Preciosa. As mudan?as anat?micas, observadas durante o amadurecimento nos est?dios de matura??o, foram mais evidentes no gen?tipo suscet?vel 017041-01. Maiores valores da vari?vel AF e maior deposi??o de lignina nos feixes vasculares mostraram-se relacionados ? resist?ncia ao despencamento. Os valores dos Ct (cycle threshold) foram utilizados para determinar a diferen?a da express?o g?nica relativa dos genes modificadores da parede celular (PEL1, EXP1 e XTH4) entre diferentes est?dios de matura??o na zona de despencamento (ZD) e na regi?o mediana da casca (zona controle - ZC). Para realizar a an?lise de express?o relativa, foi utilizado o m?todo 2? ?? CT. Os resultados finais da an?lise por RT-qPCR mostraram que houve uma express?o diferencial entre os est?dios de matura??o nos gen?tipos estudados. Os genes PEL1 e XTH4 demonstraram perfis de express?o relacionados com o despencamento dos frutos em diferentes gen?tipos sendo bons candidatos para estudos funcionais em bananeira, podendo ser utilizado para direcionar o programa de melhoramento da cultura visando ? produ??o de frutos com resist?ncia para essa caracter?stica.
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Cobeña, Ruiz Gloria Annabell. "Relação entre componentes da parede celular e atividade enzimática no pedicelo e a suscetibilidade de bananas ao despencamento natural." Universidade Federal de Viçosa, 2003. http://www.locus.ufv.br/handle/123456789/10309.
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Programa de Modernización del Sector Agropecuario
Um dos maiores problemas na comercialização de bananas é o destacamento individual dos frutos das pencas, fazendo que estes percam ou diminuam seus valores comercial e nutricional, além de contribuir para que as perdas pós-colheita atinjam cerca de 40% da produção brasileira. O presente trabalho teve como objetivos caracterizar o comportamento dos componentes da parede celular, de amido e açúcares solúveis; determinar a atividade enzimática de poligalacturonase (PG), pectinametilesterase (PME) e xilanase na região do pedicelo de duas variedades e um híbrido de banana resistente e suscetível ao despencamento natural durante o amadurecimento; e estabelecer a relação entre o comportamento dos componentes da parede celular e a atividade enzimática, bem como a suscetibilidade de bananas à queda natural. Foram utilizados os genótipos triplóides ‘Terra’ (AAB) e ‘Prata’ (AAB) e o híbrido tetraplóide SH-3640 (AAAB). Os resultados evidenciaram uma diferença de comportamento na consistência da polpa entre os genótipos estudados, com a ressalva de que ‘Terra’ apresentou a maior consistência em todos os seus estádios de amadurecimento, seguido de ‘Prata’ e ‘SH-3640’. Verificou-se também que o genótipo ‘Terra’ mostrou resistência ao despencamento, mesmo estando seus frutos maduros, ao contrário de ‘SH-3640’, que, já a partir do estádio 5 (fruto amarelo com pontas verdes), exibiu suscetibilidade à queda. Em todos os estádios de amadurecimento, o genótipo ‘Terra’ teve os maiores teores de matéria seca. Por sua vez, o genótipo ‘SH-3640’ sempre manteve os mais baixos teores. Quanto à taxa respiratória, embora se tenha elevado com o amadurecimento, em nenhum dos três genótipos estudados foi observado comportamento climatérico típico. Do total das frações dos carboidratos estruturais (celulose, hemicelulose e pectina) e não-estruturais (amido, açúcares solúveis redutores e não-redutores), os genótipos ‘SH-3640’ e ‘Prata’ tiveram por volta de 80 e 70% de carboidratos estruturais no fruto verde, mantendo-se relativamente constantes durante o amadurecimento. Nesses cultivares, houve redução na proporção de amido e aumento na de açúcares solúveis, principalmente dos redutores. Já o genótipo ‘Terra’ apresentou variações mais evidentes com relação aos outros dois. Nesse genótipo, diminuíram os teores de pectinas no decorrer do amadurecimento, enquanto os de amido se mantiveram altos mesmo no fruto maduro. Entre as enzimas estudadas, os resultados evidenciaram um papel mais importante de PME e PG na queda de fruto e confirmaram a maior resistência do genótipo ‘Terra’ ao despencamento, permitindo concluir que PG e PME são as enzimas-chave na solubilização da parede celular que acompanha o amadurecimento e, portanto, têm papel fundamental na indução do despencamento natural. A alta suscetibilidade ao genótipo SH-3640 ao despencamento está associada à elevada atividade de PG e PME e ao baixo teor de matéria seca; a maior resistência ao despencamento do genótipo ‘Terra’ está relacionada com o maior acúmulo de matéria seca e amido no pedicelo.
One of the greatest problems for banana commercialization is finger drop of ripe bananas from the bunch since the market as well as the nutritional value of such isolated fruits is reduced or lost. This contributes to post-harvest losses of about 40% of the Brazilian production. In this study, the behavior of the cell wall components, starch, and soluble sugars was characterized; the enzymatic activity of polygalacturonase (PG), pectinmetylesterase (PME), and xylanase in the pedicel region of two varieties and one hybrid determined; and the relation between the behavior of cell wall components, enzyme activities in the pedicel, and the susceptibility of bananas to natural fruit dropping established. The triploid genotypes ‘Terra’ (AAB) and ‘Prata’ (AAB), and the tetraploid hybrid SH- 3640 (AAAB) were used. Results showed a difference in the pulp consistence of the studied genotypes. ‘Terra’ presented the highest consistence throughout all ripening stages, followed by ‘Prata’ and then ‘SH-3640’. Even when the fruits were ripe, ‘Terra’ was most resistant against fruit dropping, while ‘SH-3640’ began to present a high susceptibility to fruit dropping from stage 5 on (yellow fruits with green tips). At all ripening stages, ‘Terra’ presented the highest dry matter content, while ‘SH-3640’ continuously maintained the lowest content. In none of the studied genotypes the respiration rate obeyed a typical climacteric behavior, in spite of increases during the ripening process. Of all carbohydrate structural (cellulose, hemicellulose, and pectin) and non-structural (starch, soluble reducing and non-reducing sugars) fractions, the genotypes ‘SH-3640’ and ‘Prata’ contained around 70 and 80%, respectively, of structural carbohydrates in the green fruits. This proportion remained relatively constant during the ripening process. In these cultivars, there was a reduction in the starch proportion and an increase of soluble sugars, mainly of reducing sugars. The genotype ‘Terra’, on the other hand, presented more evident variations than the other two: there was a reduction of pectin contents during the ripening process (from 2.1 to 0.47%), while the starch contents remained above 2% even in ripe fruit. The ’Terra’ genotype proved to be the most resistant against fruit dropping. Results evidenced the importance of PG and PME for the degradation, or simply, the solubilization of cell wall components during the ripening process, and, therefore, for natural fruit dropping. The high susceptibility of the SH-3640 genotype is related to the high PG and PME activity and the low dry matter content. In the case of ‘Terra’, the high resistance to finger drop is related to a greater accumulation of dry matter and starch in the pedicel.
Não foram localizados o cpf e o curriculo lattes do autor.
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Amanzougaghene, Nadia. "Résistance et évolution des poux humains, Pediculus Humanus." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0268.
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Dans ce travail, nous avons voulu apporter notre contribution dans le domaine de la recherche sur les poux humains, afin d’en savoir plus sur l’origine et la phylogéographie des clades, les pathogènes qui leurs sont associés et comprendre les mécanismes impliqués dans la résistance à l’ivermectine. Nous avons obtenu des résultats concrets dans chacune des thématiques abordées. En effet, nous avons (i) pour la première fois rapporté la présence de clade B au Moyen-Orient datant de plus de 2000 ans, supportant une origine asiatique pour ce clade, (ii) mis en évidence l'existence d'un nouveau clade mitochondrial (Clade F), (iii) mis en place une nouvelle technique de PCR en temps réel pour l’identification moléculaire rapide des clades de poux, (iv) mis en évidence chez des poux de tête la présence de l’ADN de plusieurs bactéries, dont plusieurs bactéries qui ne sont pas habituellement vectorisées par les poux telles que Coxiella burnetii, Rickettsia aeschlimannii et de potentielles nouvelles espèces de genre Anaplasma et Ehrlichia ont été détectées pour la première fois chez les poux. Enfin, nous rapportons des données nouvelles sur la résistance des poux à l’ivermectine : (v) en mettant en évidence la présence de trois mutations non-synonymes au niveau de GluCl des poux cliniquement résistants à l’ivermectine, (vi) et en démontrant, pour la première fois, chez une population de poux de laboratoire résistante à l’ivermectine qu’une répression significative de la complexine est à l’origine de la résistance. Cette découverte représente la première évidence liant la complexine à la résistance aux insecticidesIn this thesis, we are interested in studying human lice and we aimed to learn more about the origin and phylogeography of clades, lice-borne associated pathogens and to investigate potential mechanisms underlying resistance to ivermectin in lice. We obtained concrete results that have led to scientific publications. Indeed, (i) we reported for the first time the existence of the clade B in the Middle East, dating approximately to 2,000 years old, supporting an Asian origin for this clade, (ii) we highlighted the existence of a sixth mitochondrial clade (Clade F), (iii) we developed a new qPCR for a quick molecular identification of all the known clades of lice, (iv) we identified the presence of the DNA of several bacterial pathogens in head lice, among which several bacteria are not usually associated with lice, such as Coxiella burnetii, Rickettsia aeschlimannii, Borrelia theileri and potential new species from the Anaplasma and Ehrlichia. We finally, investigated mechanisms underlying resistance to ivermectin in lice: (v) we have identified, for the first time, the occurrence of three non-synonymous mutations in GluCl gene in clinically confirmed ivermectin resistant head lice, (vi) and we have identified the involvement of neuronal protein, a complexin, in laboratory ivermectin-selected resistant lice. This finding represents the first evidence linking complexin to insecticide resistance
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Nevière, Rémi. "Oxygenotherapie hyperbare et lambeaux pedicules : etude de la survie de 15 lambeaux pedicules : valeur predictive de la mesure des po2 transcutanees." Lille 2, 1989. http://www.theses.fr/1989LIL2M274.
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Boyadjis, Melanie. "Intraoperative neurophysiological monitoring through pedicle screw stimulation." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/672359.
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OBJECTIVES: Study the interdependence between stimulus duration and stimulus strength, to observe if by changing the stimulus duration, the current threshold levels will also change during pedicle screw stimulation. Then comparing the pedicle screw threshold data to 3-Dimensional imaging to confirm the effectiveness of pedicle screw stimulation.
BACKGROUND: This study examined the stimulus parameters of triggered electromyography in the operating room during posterior spinal fusions with pedicle screw fixation, and how changing stimulus duration would affect the threshold value of a pedicle screw. Triggered Electromyography (t-EMG) or pedicle screw stimulation has been used for years as Gold Standard to test whether pedicle screws are properly placed or well insulated by bone in the pedicle of the vertebrae. In a triggered EMG test, a stimulus is sent to the pedicle screw, when the electrical stimulus activates nervous tissue, a compound muscle action potential is elicited, at this point a current threshold value is recorded. This threshold is compared to normative values, which determine if the screw is located intrapedicular or has breached the pedicle wall. A breach in the pedicle wall by a pedicle screw would cause a post-operative neurological deficit, such as nerve irritation. To examine the effects duration has on threshold values, the same screw was stimulated three different times with three different durations. The threshold values were statistically evaluated to see if there was a significance between each stimulus duration and its corresponding threshold value. Duration was examined because it is often overlooked as a parameter that may change the threshold value of a triggered EMG test. Having discrepancies due to duration can produce inaccurate results which could potentially harm the patient or change the surgical protocol. It may harm the patient by leaving a screw in place that has breached the pedicle wall of a vertebrae, which will most likely cause post-operative nerve irritation. Pedicle screw stimulation is an additional modality used to verify screw placement along with radiographic imaging in the operating theatre when posterior spinal fusions are taking place.
METHODS: The current technique of pedicle screw stimulation using threshold numbers (in milliamperes) was evaluated against different stimulation parameters, and later the position of the screw was visually verified by a neurosurgeon with 3-dimensional imaging. Fundamentally, the imaging was used to validate the effectiveness that pedicle screw stimulation has on determining a well-positioned screw. Patients already scheduled to undergo spinal fusions with pedicle screw fixation were eligible for this study. A 3-Dimensional (3D) image of their spine was taken intraoperatively before insertion of spinal fixation instrumentation and one was taken after pedicle screws were inserted. These images were used to evaluate the position of the pedicle screw by a neurosurgeon. After screws were positioned, triggered EMG was utilized to check whether screws were properly placed. Screw measurements were taken from patients undergoing a posterior spinal fusion in either the thoracic, lumbar or sacral region. 213 screw measurements were taken in total from 40 patients. Factors like sex, age, height and weight were not considered for this study. The triggered EMG test threshold was then compared to the post screw insertion 3D image to verify the accuracy of the triggered EMG. In other words, the image was used to justify whether the triggered EMG test alone was an accurate indicator of a properly placed screw. In addition, the triggered EMG test itself was further evaluated, by stimulating the same screw three times, with three different stimulus durations, 300µsec, 200µsec, and 100µsec. The values produced by each stimulus duration were then compared to the corresponding stimulus threshold to see if there was a significant difference. Triggered EMG stimulus durations were assessed to see if stimulus parameter settings play a role in the threshold number. A change in stimulus duration, could change the triggered EMG threshold number, which when compared to normative data could possibly indicate a properly placed screw from a mal-positioned screw with a difference in threshold of as little as 1 milliampere. From all the stimulus parameters, a focus was put on the stimulus duration because this could directly affect the triggered EMG current threshold number, or the current value where a compound muscle action potential is elicited.
Which depending on where the threshold value fell against pre-determined normative values, could directly affect whether a screw is interpreted as well-placed or not. To summarize, each pedicle screw was tested three times, at three different stimulus durations, then the corresponding threshold numbers were compared to currently established normative data thresholds and evaluated to see if duration could affect the results of a pedicle screw’s position. Remember, thresholds have been established that deem a properly placed screw, these have been used throughout the years, but no emphasis has been given to the stimulus parameters set for these thresholds. This study evaluated the importance of setting the proper stimulus parameters, mainly the stimulus duration, when using certain normative thresholds tested at specific durations to deem a properly positioned screw in the pedicle of a vertebrae. After stimulation, 3D imaging was taken intraoperatively to compare the triggered electromyography data to the actual placement of the screws. The threshold values were compared to the 3 D image of the same screws tested, to verify if indeed these established threshold values determined well-positioned screws.
RESULTS: 213 screws were stimulated, out of the 213 screws, 2 screw measurements were excluded because stimulations were not obtained from all three durations. Thus 211 screws and 40 patients were included in this study. 211 screw measurements were taken in total from 40 patients with screws confirmed to be placed intrapedicular. The triggered EMG fell within normative data thresholds for 206 screws (98%), these screws were found to be intrapedicularly placed in the 3D imaging, which was confirmed by the neurosurgeon. Stimulation durations were found to be important in five of the screws, where there was a difference in the thresholds between the three stimulations, these were significant because the values were lying borderline on normative values, questioning if the screws were indeed well-placed or possibly causing a medial breach. These five screws were thoroughly examined by the neurosurgeon via 3-dimensional imaging and were found to be acceptable in placement, and not near nervous tissue.
CONCLUSION: Intraoperative 3D imaging has shown that triggered electromyography is a reliable indicator of properly placed pedicle screws. Statistical data has also shown that stimulus duration can affect the interpretation of a properly placed screw, and threshold values do vary with different durations. Threshold values were gathered from 211 screws at three different stimulus durations, the first at 300µsec, the second at 200µsec and the third at 100µsec. At 300µsec stimulus duration, the mean threshold value was at 27.25mA (p=0.0078). At 200µsec stimulus duration, the mean threshold value was at 35.46mA (p=0.0028). At 100µsec stimulus duration, the mean threshold value was at 50.90mA (p=0.0676). These mean values were found to be statistically significant when run by the Kruskal-Wallis test, a non-parametric statistical significance test. Since, three groups of data were being compared, and thus were not normally distributed, a non-parametric significance test was used. In conclusion, the stimulus duration should be considered when using certain thresholds to interpret data.
Different durations change the stimulus strength and thus, affect the results of the screw stimulation thresholds.
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BAPTISTA, LOUIS. "Lambeaux fascio-cutanes pedicules des membres : classification et repertoire." Toulouse 3, 1990. http://www.theses.fr/1990TOU31210.
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Peock, Susan. "The screening, action and use of repellents against Pediculus humanus." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624578.
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Pereira, Marlon Cristian Toledo. "Caracterização, anatomia do pedicelo, fisiologia e redução do despencamento natural de bananas após a colheita." Universidade Federal de Viçosa, 2002. http://www.locus.ufv.br/handle/123456789/10242.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
O despencamento natural de bananas maduras é indesejável comercialmente, pois reduz o valor de mercado da fruta, bem como a sua aceitação pelos consumidores, o que pode inviabilizar o lançamento de novos cultivares. O presente trabalho teve como objetivos quantificar a suscetibilidade ao despencamento natural dos frutos de bananeira de diversos genótipos, de grupos genômicos e ploidias diferentes; obter subsídios para o melhoramento da bananeira; determinar as causas anatômicas e fisiológicas associadas ao despencamento natural de frutos de bananeira; identificar uma possível região ou camada de abscisão em frutos de bananeira; e verificar o efeito de aplicações na pré-colheita de cálcio na redução do despencamento natural dos frutos de bananeira. Os resultados evidenciaram alta resistência ao despencamento dos genótipos pertencentes ao grupo genômico BB (Butuhan, Piraí e BB França), ‘Terra’ (AAB), ‘Poteau Nain’ (tipo figo) (ABB) e ‘Thap Maeo’ (AAB), enquanto ‘Prata Anã’ (AAB), ‘Grande Naine’ (AAA), Ambrosia (AAAA), ‘Ouro’ (AA) e FHIA -18 (AAAB) apresentaram valores intermediários de resistência ao despencamento. Com relação às bananeiras com baixa resistência, destacam-se os híbridos melhorados Pioneira (AAAB), YB42-21 (AAAB), Bucaneiro (AAAA) e Calypso (AAAA) e o cultivar Ouro da Mata (AAAB). Verificou-se grau de associação de 74% entre a firmeza do fruto e a resistência ao despencamento natural. Ao contrário da maioria das plantas, na região de despencamento do fruto maduro da bananeira não foi detectado camada de abscisão. Em genótipos como Pioneira (AAAB), ‘Prata Anã’ (AAB) e ‘Lidi’ (AA), o tecido parenquimático do pedicelo degenerou-se nos frutos maduros, formando grandes espaços vazios, que justificam a maior suscetibilidade dos frutos de tais genótipos ao despencamento. O cultivar Terra (AAB), considerado resistente ao despencamento, possui fibras difíceis de serem separadas ou individualizadas e relativamente finas em relação às dos demais genótipos. Observou-se que os genótipos Butuhan (BB), ‘Poteau Nain’ (ABB) e ‘Thap Maeo’ (AAB), também resistentes ao despencamento, apresentaram fibras com paredes celulares bastante espessas. Verificou-se redução linear da resistência ao despencamento e do tempo de maturação do fruto com o incremento das concentrações de CaCl2. A firmeza não se alterou em relação às concentrações, porém em três aplicações de CaCl2 os frutos apresentaram-se mais consistentes do que com apenas uma aplicação. Os teores de cálcio da casca e da polpa dos frutos não foram alterados significativamente com as concentrações e épocas de aplicações do CaCl2, indicando baixa absorção desse nutriente quando aplicado em pré-colheita diretamente no fruto.
Natural fruit dropping of ripe bananas is commercially unwelcome, as it reduces the market value of the fruit as well as its consumer acceptance and may thwart the launch of new cultivars. In this study, goals were set as follows: quantification of the susceptibility to natural fruit dropping in fruits from different genotypes and different genomic groups and ploidies, obtainment of subsidies for banana improvement; determination of anatomical and physiological causes linked to natural dropping in banana fruits, identification of a possible abscission region or layer in banana fruits, and the verification of the effect of pre-harvest calcium application on the reduction of natural banana fruit dropping. Results showed a high resistance against fruit dropping among genotypes that belong to the genomic group BB ('Butuhan', 'Piraí' and 'BB França'), ‘Terra’(AAB), ‘Poteau Nain’ (fig type) (ABB) and ‘Thap Maeo’(AAB), while ‘Prata Anã (AAB), 'Grande Naine' (AAA), 'Ambrosia' (AAAA), ‘Ouro’ (AA) and 'FHIA –18' (AAAB) presented intermediate values of resistance against dropping. Among banana plants with low resistance, the improved hybrids Pioneira (AAAB), YB42-21 (AAAB), Bucaneiro (AAAA) and Calypso (AAAA) and the cultivar Ouro da Mata (AAAB) were outstanding. An association degree of 74% between fruit firmness and resistance against fruit dropping was established. In contrast to the majority of plants, no abscission layer was found in the region of dropping of ripe banana fruits. In genotypes like 'Pioneira' (AAAB), ‘Prata Anã’ (AAB) and ‘Lidi’ (AA), the pedicel parenchyma tissue was degenerated in the ripe fruits, forming large empty spaces, which justifies the higher susceptibility of the fruits of these genotypes to dropping. The ‘Terra’ cultivar, considered dropping resistant, owns relatively fine fibers, difficult to separate or individualize in comparison to t e h other genotypes. The genotypes 'Butuhan', (BB), ‘Poteau Nain’ (ABB) and ‘Thap Maeo’ (AAB), also dropping resistant, presented fibers with particularly thin cell walls. A linear reduction of the fruit dropping resistance and maturation period was verified in response to increased CaCl2 concentrations. The firmness did not alter in relation to the concentrations, however after three CaCl2 applications, the fruits proved to be more consistent than after only one application. Calcium contents in fruit pericarp and pulp did not vary significantly in relation to concentrations and periods of CaCl2 applications, indicating low absorption of this nutrient when applied directly on the fruit in pre-harvest.
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TOLEDANO, ELIE. "Neovascularisation d'un lambeau cutane expanse a pedicule monovasculaire : etude experimentale preliminaire sur le porc." Clermont-Ferrand 1, 1993. http://www.theses.fr/1993CLF1MS26.
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Gouraud, Gisèle. "Chimioprévention et traitements actuels des pédiculoses phénomènes de résistance." Paris 5, 1993. http://www.theses.fr/1993PA05P020.
Full textBooks on the topic "Pedicels"
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Demir, Teyfik, and Cemile Basgül. The Pullout Performance of Pedicle Screws. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-16601-8.
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Maṅgolapurī, Rādheśyama. Sāikila rikśe kā sāmrājya: Rāshṭrīya Rājadhānī Parikshetra meṃ sāikila rikśe kā astitva aura saṅgharsha. Naī Dillī: Iṃsṭiṭyūṭa phôra Ḍemokresī eṇḍa Sasṭenebiliṭī, 2014.
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Massard, Jean-Louis. Bangladesh rickshaw: Traversée partielle du sous-continent en rickshaw. Cholet: 2 encres, 2012.
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Henri, Nicot Bernard, ed. Le planificateur et le cyclopousse: Les avatars de la politique des transports urbains en Inde. Caen: Paradigme, 1986.
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Le pou de l'homme, Pediculus humanus, Linné, 1758: Observations biologiques : évaluation de l'activité de différents insecticides. Paris: Editions de l'ORSTOM, 1985.
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A slow ride into the past: The Chinese trishaw industry in Singapore, 1942-1983. Clayton, Victoria: Monash University Publishing, 2013.
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Aviv, Jonathan E. Fundamentals of head and neck reconstruction I: The angiosome concept and pedicled myocutaneous flaps. Alexandria, VA: American Academy of Otolaryngology--Head and Neck Surgery Foundation, 1997.
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Agarwal, Anil, Neil Borley, and Greg McLatchie. Breast surgery. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199608911.003.0005.
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This chapter provides essential information for common breast operations. Techniques of fine-needle aspiration cytology and core biopsy are described. Operations include incision and drainage of breast abscess, excision of benign breast lump, and wide local excision. Mastectomy, sentinel node biopsy, axillary clearance, and fine wire localization are described. Other operations include microdochectomy and the Hadfield–Adair procedure. Breast reconstruction operations include implant-based reconstruction, latissimus dorsi myocutaneous flap, transvers rectus abdominis myocutaneous pedicled flap (TRAM) and free TRAM, and deep inferior epigastric perforation (DIEP) free flap. Reduction mammoplasty operations described are inferior pedicle mammoplasty and medial pedicle breast reduction (Hall Findlay or Snowman technique).
Book chapters on the topic "Pedicels"
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Frank, J. Howard, J. Howard Frank, Michael C. Thomas, Allan A. Yousten, F. William Howard, Robin M. Giblin-davis, John B. Heppner, et al. "Pedicel." In Encyclopedia of Entomology, 2778. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6359-6_2826.
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Chiu-Collins, Lynn L., Amit D. Bhrany, and Craig S. Murakami. "Pedicle." In Encyclopedia of Otolaryngology, Head and Neck Surgery, 2115. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-23499-6_200210.
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Ringelmann, R., and Beate Heym. "Pediculus humanus." In Parasiten des Menschen, 200–201. Heidelberg: Steinkopff, 1991. http://dx.doi.org/10.1007/978-3-642-85397-5_71.
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Bricout, Nathalie. "Pedicled omentoplasty." In Breast surgery, 399–401. Paris: Springer Paris, 1996. http://dx.doi.org/10.1007/978-2-8178-0926-7_38.
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Higgins, H. William, and Jeremy Bordeaux. "Pedicle Flaps." In Evidence-Based Procedural Dermatology, 73–83. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-02023-1_8.
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Karamanos, Efstathios, Bao-Quynh Julian, and Douglas T. Cromack. "Pedicle Characteristics." In Comprehensive Atlas of Upper and Lower Extremity Reconstruction, 37–38. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-74232-4_6.
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Mehlhorn, Heinz. "Pediculus humanus capitis." In Encyclopedia of Parasitology, 2102–5. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-43978-4_2352.
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Mehlhorn, Heinz. "Pediculus humanus corporis." In Encyclopedia of Parasitology, 2105–6. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-43978-4_2353.
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Hou, Chunlin, Shimin Chang, Jian Lin, and Dajiang Song. "Pedicled Perforator Flaps." In Surgical Atlas of Perforator Flaps, 15–25. Dordrecht: Springer Netherlands, 2015. http://dx.doi.org/10.1007/978-94-017-9834-1_4.
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Mehlhorn, Heinz. "Pediculus Humanus Capitis." In Encyclopedia of Parasitology, 1–5. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-642-27769-6_2352-2.
Full textConference papers on the topic "Pedicels"
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Alzebdeh, Khalid I., Mahmoud M. A. Nassar, and Nasr Al-Hinai. "Development of New Eco-Composites From Natural Agro-Residues and Recycled Polymers." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23536.
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Abstract Wood plastic composite materials have shown a remarkable performance in various applications due to its inherent properties like strength, durability, and lightweight over conventional composite materials. However, utilization of wood as an organic filler for polymers poses a serious negative impact to the green areas. Therefore, utilization of agro-residues as organic fillers instead of wood offers a sustainable solution to the aforementioned problem. In this context, this study aims to investigate the potential use of date palm pedicel agro-residues as natural fillers in eco-composites in which recycled post-consumer polypropylene is used as a matrix. Three levels of date palm flour content, namely, 10 v.%, 20 v.% and 30 v.% are used. The influence of the date palm pedicels flour content on the mechanical, physical and thermal behavior of the developed eco-composites is examined. Material properties of the fabricated eco-composites are characterized experimentally according to ASTM standards. Thermogravimetric analysis (TGA) is also performed to assess the thermal decomposition of the developed composites. Moreover, the morphology of fractured regions is captured using Scanning Electron Microscope (SEM). Generally, adding natural fillers to the polymer matrix is a cost effective option. However, it also slightly affects tensile strength, elongation, and flexural strength at break and enhance the Young’s modulus compared to the neat polypropylene. Interestingly, it is observed that the recycled polypropylene based composites are more repellent to water absorption in comparison to the virgin polypropylene-based composites. This attribute might be due to the surface quality transformation for the reprocessed plastic polymer.
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McLachlin, Stewart D., Khalid Al Saleh, Kevin R. Gurr, Stewart I. Bailey, Chris S. Bailey, and Cynthia E. Dunning. "Comparative Assessment of Sacral Screw Loosening Augmented With PMMA Versus a Calcium Triglyceride Bone Cement." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19383.
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Instrumentation failure in the S1 pedicles as a result of the screw loosening created by large cyclic bending loads is well documented. Biomechanical studies have shown that pedicle screw augmentation with Polymethylmethacrylate (PMMA) can result in improved screw-bone interface strength [1].
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Felicia, Suciu, Arcuș Mariana, Roșca Adrian Cosmin, Bucur Laura, Popescu Antoanela, and Badea Victoria. "RESEARCH ON THE BOTANICAL AND PHARMACOGNOSTIC PARTICULARITIES OF THE INDIGENOUS SPECIES LYSIMACHIA NUMMULARIA L." In GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/20.
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"Preliminary pharmacochemical research on Lysimachia nummularia L. was performed by dint of pharmacognostic analysis (macroscopic examination, global chemical analysis, preliminary quantitative determinations).The article includes the analysis of the macroscopic characters of the vegetative organs (root, stem and leaf), as well as of the reproductive organs (flower, fruit, seed) belonging to the spontaneous native species Lysimachia nummularia L. Morphological features were described and discussed. The identification of these aspects was done with the naked eye, but also with the help of a hand magnifier and a binocular magnifier. The results revealed that the external appearance of the plant justifies the species belonging to the genus Lysimachia, family Primulaceae. They are found in the glabrous and creeping appearance of the plant, opposite, almost round leaves, solitary, yellow flowers, axillary with vigorous pedicels, perianth pentamer, actinomorphic, dialisepal and dialipetal, globular capsule fruit. The semi-hydrophilic nature is found in the presence of adventitious roots that develop both from the rhizome and at the nodes of the stem. The preliminary quantitative determinations performed were loss by drying as well as soluble substances of the species Lysimachia nummularia L. Following the global chemical analysis, active principles known in the literature for the antioxidant potential were identified. Following the preliminary quantitative determinations (drying loss, determination of soluble substances) results comparable to those in the literature on the content of volatile substances and soluble substances were obtained."
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Li, Lei, Zhaohua Chang, Xuelian Gu, and Chengli Song. "Design and Research of Interspinous Lumbar Non-Fusion Device." In ASME 2010 5th Frontiers in Biomedical Devices Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/biomed2010-32064.
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Objective: Long term clinical data showed that lumbar fusion for Lumbar spinal stenosis (LSS) and lumbar disc degeneration (LDD) therapy could change the loads of disc and articular facet and increase the motion of adjacent segments which lead to facet arthropathy and adjacent level degeneration. This study is to design and analyze an interspinous process device (IPD) that could prevent adjacent level degeneration in the LSS and LDD therapy. Method: The IPD was designed based on anatomical parameters measured from 3D CT images directly. The IPD was inserted at the validated finite element model of the mono-segmental L3/L4. The biomechanical performance of a pair of interbody fusion cages and a paired pedicel screws were studied to compare with the IPD. The model was loaded with the upper body weight and muscle forces to simulate five loading cases including standing, compression, flexion, extension, lateral bending and axial rotation. Results: The interbody fusion cage induced serious stress concentration on the surface of vertebral body, has the worst biomechanical performance among the three systems. Pedicle screws and interbody fusion cage could induce stress concentration within vertebral body which leads to vertebral compression fracture or screw loosening. Regarding to disc protection, the IPD had higher percentage to share the load of posterior lumbar structure than the pedicel screws and interbody fusion cage. Conclusion: IPD has the same loads as pedicle screw-rod which suggests it has a good function in the posterior stability. While the IPD had much less influence on vertebral body. Furthermore, IPD could share the load of intervertebral discs and facet joints to maintain the stability of lumbar spine.
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Rahyussalim, Ahmad Jabir, Tri Kurniawati, Nanda Notario Besri, and Khairul Hukmi. "Osteoporotic pedicle screw: Review of various types of pedicle screw and cement augmentation." In THE 4TH BIOMEDICAL ENGINEERING’S RECENT PROGRESS IN BIOMATERIALS, DRUGS DEVELOPMENT, HEALTH, AND MEDICAL DEVICES: Proceedings of the International Symposium of Biomedical Engineering (ISBE) 2019. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5139323.
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Canfarotta, Michael, Zainab Farzal, Satyan Sreenath, Adam Kimple, Charles Ebert, Adam Zanation, and Brian Thorp. "Pedicled Nasoseptal Flap Outcomes: An Update." In 29th Annual Meeting North American Skull Base Society. Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-1679846.
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Yahya, Fachmi Ian, Noor Fatimah Mediawati, and Mochammad Tanzil Multazam. "Motorized Pedicabs in Indonesia’s Legislative Framework." In 1st Annual International Conference on Natural and Social Science Education (ICNSSE 2020). Paris, France: Atlantis Press, 2021. http://dx.doi.org/10.2991/assehr.k.210430.057.
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Behrbalk, Eyal. "Pedicle Screw Placement and Augmentation." In eccElearning Postgraduate Diploma in Spine Surgery. eccElearning, 2017. http://dx.doi.org/10.28962/01.3.139.
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Kiapour, A., K. Sairyo, T. Terai, V. K. Goel, and N. A. Ebraheim. "Bilateral Laminar Hook Placements Reduces Pedicle Screw Pull Outs in Long Pedicle Screw Fixation." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19357.
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The pedicle screw (PS) system has been widely used for the spinal reconstruction. Even for the osteoporotic spine, PS system has been the first choice for the instrumentation. However, the usage of PS in the porotic spine seems to be challenging. When the PS is inserted in the osteoporotic vertebrae, the PS is sometimes loosened; eventually, it shows back out, because the PS cannot hold bones with osteoporosis efficiently [1,2].
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Tia, Samuel Q., Jennifer M. Buckley, Thuc-Quyen Nguyen, Jeffrey C. Lotz, and Shane Burch. "A Novel Technique for Measuring Pedicle Screw Forces In Situ." In ASME 2008 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/sbc2008-192219.
Full textAbstract:
Long posterior fusion constructs in the lumbar spine cause substantial posteriorly directed loading of the supporting pedicle screws, particularly during patient bending activities. Although there are numerous documented accounts of clinical failure at the pedicle screw-bone interface [1,2], the in situ pull-out strength of pedicle screws in long surgical constructs has not been characterized. Previous biomechanical studies have quantified pedicle screw pull-out force in cadaveric models through destructive testing or in nondestructive cases, through the use of custom-machined pedicle screws instrumented with strain gages [3–6]. However, these techniques involve altering screw geometry and may fail to properly simulate in vivo mechanical loading conditions. The goal of this study was to develop and validate a sensor system for measuring pedicle screw pull-out forces in long posterior constructs in situ during multi-segmental cadaveric testing.
Reports on the topic "Pedicels"
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Pedicled preputial tube urethroplasty for bulbar necrosis in PFUDD. BJUI Knowledge, October 2018. http://dx.doi.org/10.18591/bjuik.v019.
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