Evaluation au champ des caracteristiques agromorphologiques de certaines varietes de riz nerica testees au Sud-Est du Gabon

L’intensification de la riziculture constitue un défi majeur pour le Gabon  dans sa stratégie de lutte pour la sécurité alimentaire de la population. A cet effet, six variétés de riz NERICA issues de la sélection participative (PVS) ont été retenues. L’essai a été conduit à partir de 2009 à MASUKU dans le Haut-Ogooué. Les paramètres agromorphologiques tels que le tallage et la hauteur des plants et les composantes de rendement  (nombre de panicules / m2, nombre de grains / panicule, poids de 1 000 grains, taux de stérilité) ont été évalués durant la phase végétative. Les résultats des travaux ont été assez concluants. Les six nouvelles variétés ont présenté les caractéristiques suivantes : une bonne aptitude au tallage (plus de 350 talles au m2), une taille moyenne assez élevée (supérieure à 120 cm), un nombre de panicules au m2 appréciable (supérieur à 220 par m2), un poids de 1 000 grains (supérieur à 25 g). Les rendements enregistrés varient entre 4 200 kg/ha pour le NERICA 11 et 7 150 kg/ha pour le NERICA 14. Il ressort de ces résultats que les NERICA s’adaptent assez bien aux conditions écologiques du MASUKU et méritent par conséquent d’être vulgarisées dans les plaines rizicoles de la localité.Mots clés : Riz pluvial, NERICA, paramètres agromorphologiques, Gabon

Changing concepts in plant hormone action

Summary: A plant hormone is not, in the classic animal sense, a chemical synthesized in one organ, transported to a second organ to exert a chemical action to control a physiological event. Any phytohormone can be synthesized everywhere and can influence different growth and development processes at different places. The concept of physiological activity under hormonal control cannot be dissociated from changes in concentrations at the site of action, from spatial differences and changes in the tissue's sensitivity to the compound, from its transport and its metabolism, from balances and interactions with the other phytohormones, or in their metabolic relationships, and in their signaling pathways as well. Secondary messengers are also involved. Hormonal involvement in physiological processes can appear through several distinct manifestations (as environmental sensors, homeostatic regulators and spatio-temporal synchronizers, resource allocators, biotime adjusters, etc.), dependent on or integrated with the primary biochemical pathways. The time has also passed for the hypothesized ‘specific' developmental hormones, rhizocaline, canlocaline, and florigen: root, stem, and flower formation result from a sequential control of specific events at the right places through a coordinated control by electrical signals, the known phytohormones and nonspecific molecules of primary and secondary metabolism, and involve both cytoplasmic and apoplastic compartments. These contemporary views are examined in this revie

A workflow system as an information support to companies operating in the area of sustainable construction

Doktorska disertacija obravnava področje dostopnosti informacij, pomembnih za odločanje o izbiri storitev in proizvodov pri prenovi stavbe. Te so pogosto neurejene in razpršene po celotnem spletu ter zapisane v različnih formatih. Posledično je lahko iskanje želenih informacij zelo zamudno in nepregledno. Informacije lahko zajamemo v delotoku, ki predstavlja zaporedje povezanih storitev, izvajanih v primerno orkestriranih korakih. Osnovna hipoteza trdi, da lahko model informacijskega sistema delotokov zajame visoko stopnjo ključnih informacij in znanj na področju trajnostne gradnje in načrtovanja ter kot tak predstavlja primerno informacijsko podporo gradbenim podjetjem in investitorjem. Potrebe po informacijski podpori ugotavljamo s pomočjo raziskave med ključnimi deležniki na področju gradbeništva. Rezultati izvedene raziskave razkrivajo velike potrebe po dostopu do urejenih informacij in kažejo na veliko pripravljenosti deležnikov za sodelovanje ter medsebojno deljenje informacij. Izdelan je pregled obstoječih rešitev in dognanj na omenjenem področju. Predstavljen je trajnosten pogled na stavbe s pregledom najbolj razširjenih in aktualnih pristopov trajnostnega ocenjevanja stavb, ki razkriva razlike pri pripisovanju teže posameznim trajnostnim vidikom. V nadaljevanju izdelamo pregled stanja slovenskega stavbnega fonda, ki razkriva, da je velika večina stavb potencialno potrebnih prenove. Predstavljene so tudi semantične tehnologije, ki omogočajo izdelavo naprednih informacijskih sistemov in ki jih zato uporabimo v nadaljnjem delu. V nadaljevanju dela je predstavljen razvoj prototipa informacijskega sistema, ki temelji na delotokih. Opisana je zasnova arhitekture informacijskega sistema, model sprejemanja odločitev in razvita ontologija, ki podpira zapis informacij v delotoke in hrambo informacij v pripadajoči podatkovni bazi OWL/RDF. V zaključnem delu je predstavljena validacija prototipa informacijskega sistema, ki kaže, da smo uspeli zadostiti opredeljenim zahtevam. Postavljena hipoteza je torej potrjena.The research presented in this thesis is concerned with the accessibility of information on the world web, crucial for the decision making process regarding products and services required for building refurbishment. This information is often dispersed, poorly structured and written in various formats. As a consequence, information search on the web can be extremely time-consuming and difficult to carry out. The information can be sequenced in a workflow consisting of a series of interconnected services which are executed in orchestrated steps. The research hypothesis postulates that the workflow information system model is able to encompass a large proportion of key information and knowledge from the sustainable construction field. As such, it represents efficient information support to potential clients and construction contracting companies. Information support requirements of various stakeholders from the construction sector were identified by using a survey. The obtained results exhibit a clear need for structured information, as well as a significant willingness of stakeholders to share the information. An overview of the existing solutions and accomplishments in sustainable construction is presented. The concept of sustainability assessment is presented, along with an overview of the most frequently employed approaches for the sustainability assessment of buildings, which reveals differences in assigning relative importance to individual sustainability aspects. An overview of the Slovenian residential building fund is carried out. It shows that the majority of residential building stock is in need of refurbishment. Further, semantic technologies that enable the establishment of advanced information systems are presented. The second part presents the development of a workflow-based prototype information system. The design of the information system architecture is presented, together with the decision making model and the ontology that supports information recording into workflows and data storage into the OWL/RDF database. The validation of the information system is presented in the concluding part. It is shown that the system requirements defined in the beginning of the research were achievedthe initial hypothesis is therefore confirmed

A novel procedure to measure the antioxidant capacity of Yerba maté extracts

Yerba maté extracts have in vitro antioxidant capacity attributed to the presence of polyphenolic compounds, mainly chlorogenic acids and dicaffeoylquinic acid derivatives. DPPH is one of the most used assays to measure the antioxidant capacity of pure compounds and plant extracts. It is difficult to compare the results between studies because this assay is applied in too many different conditions by the different research groups. Thus, in order to assess the antioxidant capacity of yerba maté extracts, the following procedure is proposed: 100 µL of an aqueous dilution of the extracts is mixed in duplicate with 3.0 mL of a DPPH 'work solution in absolute methanol (100 µM.L-1), with an incubation time of 120 minutes in darkness at 37 ± 1 °C, and then absorbance is read at 517 nm against absolute methanol. The results should be expressed as ascorbic acid equivalents or Trolox equivalents in mass percentage (g% dm, dry matter) in order to facilitate comparisons. The AOC of the ethanolic extracts ranged between 12.8 and 23.1 g TE % dm and from 9.1 to 16.4 g AAE % dm. The AOC determined by the DPPH assay proposed in the present study can be related to the total polyphenolic content determined by the Folin-Ciocalteu assay