994 resultados para Plant morphology.


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Tämän kannattavuustutkimuksen lähtökohtana oli se, että Yhtyneet Sahat Oy:n Kaukaan sahalla ja Luumäen jatkojalostuslaitoksella haluttiin selvittää pellettitehtaan kannattavuus nykyisessä markkinatilanteessa. Tämä työon luonteeltaan teknis-taloudellinen selvitys eli ns. feasibility study. Pelletöintiprosessi on tekniikaltaan yksinkertainen eikä edellytä korkea teknologian laitteita. Toimiala on maailmanlaajuisesti varsin uusi. Suomessa pellettimarkkinat ovat vielä pienet ja kehittymättömät, mutta kasvua on viime vuosina tapahtunut. Valtaosa kotimaan tuotannosta menee vientiin. Investoinnin laskentaprosessissa saadut tuotannon alkuarvot sekä kustannusrakenteen määrittelyt ovat perustana varsinaisille kannattavuuslaskelmille. Laskelmista on selvitetty investointeihin liittyvät yleisimmät taloudelliset tunnusluvut ja herkimpiä muuttujia on tutkittu ja pohdittu herkkyysanalyysiä apuna käyttäen.

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Tutkielman tavoitteena on määritellä projektikontrolloinnin ja - riskijohtamisen roolit ja toiminnot saksalaisissa kone- ja tehdassuunnitteluteollisuusyrityksissä. Tämä on kvalitatiivinen tutkielma, jossa käytetään voimakkaasti kuvailevia metodeita. Materiaali tutkimuksen empiiriseen osaan kerättiin kyselykaavakkeen avulla. Kyselykaavakkeiden tulokset käsiteltiin Microsoft Office Access- ohjelmalla ja analysoitiin Microsoft Office Excel- ohjelmalla ja Pivot table- työkalun avulla. Tutkimustulokset osoittavat, että asianmukaisessa projektikontrollointi- ja riskijohtamismetodien käytössä ja käyttötiheydessä esiintyy puutteita saksalaisissa kone- ja tehdassuunnitteluteollisuusyrityksissä. Tehostamalla ja keskittymällä enemmän projektikontrollointi- ja riskijohtamismetodeihin ja prosesseihin sekä projektien että yritysten suorituskyky paranisi.

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Infectious hepatitis C virus (HCV) particle assembly starts at the surface of lipid droplets, cytoplasmic organelles responsible for neutral fat storage. We analysed the relationship between HCV and seipin, a protein involved in lipid droplet maturation. Although seipin overexpression did not affect the total mean volume occupied by lipid droplets nor the total triglyceride and cholesterol ester levels per cell, it caused an increase in the mean diameter of lipid droplets by 60 %, while decreasing their total number per cell. The latter two effects combined resulted in a 34 % reduction of the total outer surface area of lipid droplets per cell, with a proportional decrease in infectious viral particle production, probably due to a defect in particle assembly. These results suggest that the available outer surface of lipid droplets is a critical factor for HCV release, independent of the neutral lipid content of the cell.

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[eng] The group of teaching innovation in the area of Botany (GIBAF), University of Barcelona (UB), is raised each year to design new accreditation activities under continuous evaluation framework. We present the experience carried out during the academic year 2008-09 in the course of Pharmaceutical Botany. The aim has been to involve students for a semester in the authorship of a tutored project immediately useful and of easy permanence, beyond its assessment proving usefulness. The Medicinal Plants Garden of the Monastery of Pedralbes has been used as a resource and a collaboration agreement has been signed between the UB faculty and the Institute of Culture of Barcelona. The students have developed the work using the Moodle platform CampusvirtualUB into five stages which included preparation of files by students that have been modified in some steps following the various feedbacks from teachers. At the beginning of the activity, students were provided with a complete schedule of activities, the schedule for its implementation, and a total of 18 forced-use library resources. Finally, through Google sites, a website has been implemented, allowing for a virtual tour of the garden, documenting by referenced literature 50 medicinal plants for their nomenclature, botanical description, distribution, uses historical, current and future) and toxicity. The result of the activity was presented at a public ceremony in the Monastery of Pedralbes and is available at: http://sites.google.com/site/jardimedievalpedralbes/ [spa] El grupo de innovación docente integrado por profesores del área de Botánica (GIBAF) de la Universidad de Barcelona (UB) se plantea cada curso el diseño de nuevas actividades acreditativas en el marco de la evaluación continuada. Se presenta la experiencia llevada a cabo durante el curso 2008-09 en la asignatura Botánica Farmacéutica. El objetivo ha sido implicar durante un semestre a los estudiantes en la autoría de un proyecto tutorizado de inmediata utilidad y clara perdurabilidad, más allá de su utilidad acreditativa. Como recurso se ha utilizado el Jardín de Plantas Medicinales del Monasterio de Pedralbes y se ha firmado un convenio de colaboración docente entre la UB y el Instituto de Cultura de Barcelona. Los estudiantes han realizado el trabajo utilizando la plataforma Moodle del Campus virtual de la UB en cinco etapas que han incluido la confección de unas fichas que se han ido modificando en función de las diversas retroacciones de los profesores. Al inicio de la actividad, se facilitó a los estudiantes el cronograma completo de la actividad, la pauta para su realización, así como un total de 18 recursos bibliográficos de uso obligado. Finalmente, a través de GoogleSites, se ha realizado una web que permite realizar un paseo virtual por el jardín, documentando de forma referenciada para las 50 plantas medicinales su nomenclatura, descripción botánica, distribución, usos (históricos, actuales y futuros) y toxicidad. El resultado de la actividad fue presentado en un acto público en el Monasterio de Pedralbes y puede consultarse en: http://sites.google.com/site/jardimedievalpedralbes/

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RESUME Les bétalaïnes sont des pigments chromo-alcaloïdes violets et jaunes présents dans les plantes appartenant à l'ordre des Caryophyllales et dans les champignons des genres Amanita et Hygrocybe. Leur courte voie de biosynthèse est élucidée chimiquement depuis de nombreuses années, mais les enzymes impliquées dans cette biosynthèse chez les plantes ne sont toujours pas caractérisées. L'enzyme de la DOPA-dioxygénase d' Amanita muscaria a été identifiée (Girod et Zryd, 1991a), mais de nombreuses tentatives d'isolation d'un homologue chez les plantes ont échoué. Afin d'isoler les gènes spécifiques des bétalaïnes chez les plantes, nous avons construit des banques soustraites d'ADNc à partir d'ARN total de pétales immatures de Portulaca grandiflora (Pg) de génotypes jaunes et blancs, respectivement violets et blancs. Les clones couleur- spécifiques ont été détectés en premier par analyse Northem du RNA de pétales blancs et colorés. Les candidats positifs ont alors été soumis à une analyse de transcription au niveau des tiges colorées, vertes et des feuilles, afin d'établir leur expression spécifique. Deux ARNs messagers complets ont une expression corrélée avec l'accumulation des bétalaïnes dans les tissus. Le premier de ces clones, A.16, code pour une oxydase de l'acyl-Coenzyme A (ACX) putative, mais le domaine de liaison du FAD essentiel pour l'activité d'ACX est absent. Toutes nos tentatives pour démontrer sa fonction ont échoué. Le rôle de cette protéine dans la voie de synthèse des bétalaïnes reste inconnu. Le deuxième de ces clones spécifique aux bétalaïnes, L.6 (isolé par Zaiko, 2000), a été renommé DODA en raison de son homologie avec le domaine LigB (pfam02900) d'une 4,5-dioxygénase extradiol bactérienne. DODA a été identifié in silico comme une dioxygénase extradiol en raison de la conservation stricte, au niveau de sa séquence peptidique, des résidus catalytiques de LigB et de ceux liant le cofacteur fer. Une analyse de transfert Southem a montré que ce gène est unique dans Pg. L'expression transitoire de DODA par transformation biolistique dans des pétales blancs de Pg a produit des taches violettes ou jaunes dans des cellules transformées. Une analyse HPLC de ces taches a démontré leur identité avec les bétalaïnes présentes naturellement dans les pétales violets et jaunes de Pg, confirmant ainsi la complémentation par le gène Pg DODA de l'allèle récessif cc présent dans les pétales blancs de Pg. Des homologues de DODA (DOPA-dioxygénase) ont été identifiés dans de nombreuses espèces de plantes, y compris dans celles sans bétalaïne. L'alignement de ces homologues a permis l'identification d'un motif spécifique aux bétalaïnes à côté d'une histidine catalytique conservée. Ce motif [H-P-(S,A)-(N,D)-x-T-P] remplace le motif [H-N-L-R] conservé dans les plantes sans bétalaïne et le motif [H-N-L-x] présent dans tous les homologues bactériens et archaebactériens. Une modélisation tridimensionnelle préliminaire du site actif de Pg DODA et de son homologue dans la mousse Physcomitrella patens a montré l'importance de ce motif spécifique aux bétalaïnes pour l'accessibilité du substrat au site actif. L'analyse phylogénétique de DODA a confirmé l'évolution séparée de cette protéine chez les plantes à bétalaïnes par comparaison avec celle des plantes sans bétalaïne. Nous avons donc conclu que les bétalaïnes sont apparues par modification de l'affinité pour un substrat d'enzymes similaires à DODA, chez un ancêtre unique des Caryophyllales qui a perdu toute capacité de biosynthèse des anthocyanes. Finalement, Pg DODA n'a aucune similarité avec la protéine DODA d' Amanita muscaria, bien que celle-ci complémente aussi la pigmentation des pétales blancs de Pg. La biosynthèse des bétalaïnes est un exemple remarquable de convergence évolutive biochimique indépendante entre espèces de règnes différents. ABSTRACT Betalains are violet and yellow chromo-alkaloid pigments present in plants belonging to the order Caryophyllales and also in the fungal genera Amanita and Hygrocybe. Their short biosynthetic pathway is chemically well understood since many years, but enzymes involved in the plant pathway are still uncharacterized. The DOPA-dioxygenase from Amanita muscaria was identified (Girod and Zryd, 1991a), but numerous attempts to identify a plant homologue to the corresponding gene, failed. In order to isolate betalain-specific genes in plants, subtractive cDNA libraries were built with total RNA from white and yellow and respectively, violet immature petals from Portulaca grandiflora (Pg) genotypes. Colour-specific clones were first detected by Northern blot analysis using RNA from white and coloured petals. Positive candidates were submitted to further transcription analysis in coloured, green stems and leaves in order to assess their specific expression. Two full-length mRNAs showed a correlated expression with betalain accumulation in tissues. One of them, A.16, encodes a putative acyl-Coenzyme A oxidase (ACX), but missing the FAD binding domain essential for the ACX activity. Thus, all attempts to demonstrate its function failed. The role of this protein in the betalain biosynthesis pathway, if any, is still unknown. The second betalain-specific mRNA, L.6 (isolated by Zaiko, 2000) shows a homology with a LigB domain (pfam02900) from a bacterial extradiol 4,5-dioxygenase. It was then renamed DODA (DOPA-dioxygenase). DODA was identified in silico as a highly conserved extradiol dioxygenase due to the strict conservation of its peptidic sequence with LigB catalytic residues and iron-binding cofactor residues. Southern blot analysis showed that this gene is a single copy-gene in Pg. Transient expression of DODA protein through biolistic transformation of Pg white petals produced violet or yellow spots in individual cells. HPLC analysis of these spots showed an identity with betalain pigments present naturally in yellow and violet Pg petals, thus confirming the complementation of the recessive cc allele present in Pg white petals by Pg DODA gene. DODA homologues were identified in numerous plant species including those without betalain. Alignment of these homologues allowed the identification of a betalain-specific pattern beside a highly conserved catalytic histidine. This [H-P-(S,A)-(N,D)-x-T-P] pattern replaces a [H-N-L-R] pattern strictly conserved in non-betalain plants and a [H-N-L-x] pattern present in all bacterial and archaebacterial homologues. Preliminary three-dimensional modeling of the active site of Pg DODA and its Physcomitrella patens moss homologue revealed the importance of this betalain-specific pattern for the substrate accessibility to the DODA active site. DODA phylogenetic analysis confirmed the separate evolution of this protein in betalain-producing plants. We conclude that betalain pigments appeared in a unique ancestor of the Caryophyllales order in which anthocyanin biosynthetic pathway was impaired, by a modification of enzymes of the DODA family for substrate affinity. The Pg DODA protein has no sequence similarity with Amanita muscaria DODA, despite the fact that they both complement Pg white petals for their pigmentation. Betalain biosynthesis is an interesting example of independent biochemical evolutionary convergence between species from different kingdoms.

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Résumé Les mousses sont la plus ancienne lignée de plantes terrestres et leur longue évolution a été accompagnée par des tendances à la simplification des caractères morphologiques. Ce phénomène a quelque peu compliqué les reconstructions phylogénétiques basées sur la morphologie. Les analyses génétiques ont permis de donner de nouvelles informations dans le cadre des analyses phylogénétiques et une réévaluation de certains caractères morphologiques. La plupart des études combinant les données morphologiques et moléculaires ne concernent que des niveaux systématiques élevés comme l'ordre ou la famille et très peu considèrent le niveau du genre. La présente étude tend à tester les relations phylogénétiques du genre Grimmia à l'aide d'une combinaison de caractères morphologiques et moléculaires. Les 40 espèces de Grimmia utilisées dans la première partie de cette étude représentent la majorité des espèces trouvées en Eurasie, un des centres de diversification du genre. Lors de l'analyse morphologique, 52 caractères morphologiques/anatomiques (33 du gamétophyte et 19 du sporophyte) ont été numérisés. Malgré le peu de support statistique des arbres, la topologie des arbres est stable. Les Grimmia, comme décrit précédemment, sont paraphylétiques. Trois clades, correspondant respectivement aux sous-genres Rhabdogrimmia Limpr, Litoneuron I.Hagen et Gasterogrimmia Schimp. sont présents, tandis que le restant des taxons appartenant aux Grimmia forment un groupe non-résolu et indistinct des autres Grimmiaceae. Les séquences chloroplastiques trnL-trnF et rps4 combinés à la morphologie ont été ensuite utilisés pour reconstruire la phylogénie des Grimmia. Les arbres obtenus soutiennent la monophylie des Grimmiaceae tandis que les Grimmia, sont paraphylétiques. Deux clades principaux correspondant aux "Rhabdogrimmia" et aux "Grimmia" se détachent. Seules les espèces de "Rhabdogrimmia" produisent des gemmules foliaires (reproduction asexuée). Dans une étude considèrant 91 séquences trrIL-trnF les espèces appartenant aux "Rhabdogrimrnia" (reproduction asexuée essentiellement) ont des variabilités intraspécifique très faible et interspécifique relativement élevée tandis que les "Grimmia" possèdent la tendance inverse (plus de reproduction sexuée). Summary The mosses are a very old land plant lineage and their long evolutionary history has been accompanied by a trend of morphological character simplifications. This phenomenon has somewhat complicated morphological based phylogenetic reconstructions. Genetic analyses have provided new insights for phylogenetic studies, and have allowed morphological data to be re¬evaluated. Most of the studies combining morphological and molecular data have concerned the higher systematic levels of order and family and only have few considered the genus. The present study aims to test the phylogenetic relationships of the genus Grimmia using a combination of morphological and molecular characters. The 40 chosen Grimmia species represent the majority of those found in Eurasia, one diversification centers of the genus. For the morphological analysis, 52 morphological/anatomical characters (33 gametophyte and 19 sporophyte characters) were numerized. Although the internal statistical support was relatively low, the tree topologies were stable. Grimmia as currently defined was found to be paraphyletic. Three subclades, corresponding to the subgenera Rhabdogrimmia Limpr., Litoneuron I.Hagen, and Gasterogrimmia Schimp. were observed in the trees, while the reminder of the Grimmia species formed an unresolved group indistinct from other Grimmiaceae. Chloroplast (trnL-trnF and rps4) DNA sequences combined with morphology were used to reconstruct the phylogeny of Grimmia. The resulting trees supported the monophyly of Grimmiaceae and that the genus Grimmia, as currently defined, as paraphyletic. Two main clades were resolved corresponding to "Rhabdogrimmia" and "Grimmia". The species belonging to "Rhabdogrimmia" produce foliar-gemmae (asexual reproduction). In a study using 91 sequences of trnL-trnF,"Rhabdogrimmia" species (mainly asexual reproduction) have very low intraspecific variability and high interspecific variability whereas the "Grimmia" species possess the inverse tendency.

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The origin of the carbon atoms in CO2 respired by leaves in the dark of several plant species has been studied using 13C/12C stable isotopes. This study was conducted using an open gas exchange system for isotope labeling that was coupled to an elemental analyser and further linked to an isotope ratio mass spectrometer (EA-IRMS) or coupled to a gas chromatography-combustion-isotope ratio mass spectrometer (GC-C-IRMS). We demonstrate here that the carbon, which is recently assimilated during photosynthesis, accounts for nearly ca. 50% of the carbon in the CO2 lost through dark respiration after illumination in fast-growing and cultivated plants and trees and, accounts for only ca. 10% in slow-growing plants. Moreover, our study shows that fast- growing plants, which had the largest percentages of newly fixed carbon of leaf-respired CO2 , were also those with the largest shoot/root ratios, whereas slow-growing plants showed the lowest shoot/root values.

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Near-infrared spectroscopy (NIRS) was used to analyse the crude protein content of dried and milled samples of wheat and to discriminate samples according to their stage of growth. A calibration set of 72 samples from three growth stages of wheat (tillering, heading and harvest) and a validation set of 28 samples was collected for this purpose. Principal components analysis (PCA) of the calibration set discriminated groups of samples according to the growth stage of the wheat. Based on these differences, a classification procedure (SIMCA) showed a very accurate classification of the validation set samples : all of them were successfully classified in each group using this procedure when both the residual and the leverage were used in the classification criteria. Looking only at the residuals all the samples were also correctly classified except one of tillering stage that was assigned to both tillering and heading stages. Finally, the determination of the crude protein content of these samples was considered in two ways: building up a global model for all the growth stages, and building up local models for each stage, separately. The best prediction results for crude protein were obtained using a global model for samples in the two first growth stages (tillering and heading), and using a local model for the harvest stage samples.

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Twelve variables were identified to define morphology in 109 calves sired by eight Pirenaica bulls widely used in artificial insemination. The effect of selection for weight at 210 days of age (W210) was detected from the regression coefficient between the 12 variables and the selection index for W210 used in the breeding plan. Unbiased estimates of the genetic correlated responses on the morphology were obtained without previously estimating the genetic correlation among traits. In Pirenaica cattle, selection for W210 increased slaughter live weight, chest depth and corporal length. The expected changes on height (withers, back and rump), rump width and thoracic perimeter were lower but positive and statistically significant.

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This work evaluated the effect of seed size and morphology on the development and biomass of durum wheat seedlings. Three different seed-grading sizes selected by sieving were used in glasshouse experiments, and a set of three developmental and 23 biomass-related indices were measured on eight genotypes, at two moisture levels. The influence of seed size on seedling development was studied at high and low temperatures (22\12 mC, and 15\5 mC day\night temperatures, respectively), in growth chambers. The area of the seed and the area of the embryo were the seed morphological traits most affected by seed size. Seed size was strongly associated with seedling development and seedling biomass until the complete extension of the first two leaves, at the fourth leaf stage. The rate of first-leaf growth and the area of the first leaf were the developmental and biomass traits, respectively, most sensitive to seed-grading size.

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We examined root morphological and functional differences caused by restrictions imposed to vertical growth in the root system of holm oak (Quercus ilex L.) seedlings to assess the consequences of using nursery containers in the development of a confined root system for this species. Thus, root morphological, topological and functional parameters, including hydraulic conductance per leaf unit surface area (K $_{\rm RL})$, were investigated in one-year seedlings cultivated in three PVC tubes differing in length (20, 60 and 100 cm). Longer tubes showed greater projected root area, root volume, total and fine root lengths, specific root length (SRL) and K$_{\rm RL}$ values than did shorter tubes. On the other hand, the length of coarse roots (diameter > 4.5 mm) and the average root diameter were greater in shorter tubes. The strong positive correlation found between K$_{\rm RL}$ and SRL (r=+0.69; P<0.001) indicated that root thickness was inversely related to water flow through the root system. We concluded that root systems developed in longer tubes are more efficient for plant water uptake and, therefore, changes in root pattern produced in standard forest containers (i.e. about 20 cm length) may in fact prevent a proper establishment of the holm oak in the field, particularly in xeric environments.

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Les plantes transgèniques són una part integral de l’agricultura contemporània. Durant l’any 2006 més de noranta milions d’hectàrees de plantes transgèniques van ser cultivades en vint-i-un països. Des de la comercialització de la primera planta transgènica el 1996 els nivells d’adopció d’aquests cultius han augmentat anualment amb percentatges de dos dígits. El desenvolupament i la comercialització de les plantes transgèniques van lligats estretament al comerç mundial, a la globalització, a la disponibilitat de suficient menjar, a la protecció del medi ambient i del consumidor i a la propietat intel·lectual. En aquest article exposem els avenços més recents i les tendències actuals en el desenvolupament dels cultius transgènics i de la seva utilització. També ens fem ressò d’alguns assumptes no científics que s’han de solucionar abans que aquests cultius arribin al màxim del seu potencial, proporcionant una agricultura més sostenible i ecològica. Finalment, ressaltarem la importància de com les plantes transgèniques poden contribuir en la disponibilitat de menjar i en la millora de la pobresa en els països en vies de desenvolupament.

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Development of the mutualistic arbuscular mycorrhiza (AM) symbiosis between most land plants and fungi of the Glomeromycota is regulated by phytohormones. The role of jasmonate (JA) in AM colonization has been investigated in the dicotyledons Medicago truncatula, tomato and Nicotiana attenuata and contradicting results have been obtained with respect to a neutral, promotive or inhibitory effect of JA on AM colonization. Furthermore, it is currently unknown whether JA plays a role in AM colonization of monocotyledonous roots. Therefore we examined whether JA biosynthesis is required for AM colonization of the monocot rice. To this end we employed the rice mutant constitutive photomorphogenesis 2 (cpm2), which is deficient in JA biosynthesis. Through a time course experiment the amount and morphology of fungal colonization did not differ between wild-type and cpm2 roots. Furthermore, no significant difference in the expression of AM marker genes was detected between wild type and cpm2. However, treatment of wild-type roots with 50 μM JA lead to a decrease of AM colonization and this was correlated with induction of the defense gene PR4. These results indicate that JA is not required for AM colonization of rice but high levels of JA in the roots suppress AM development likely through the induction of defense.