16 research outputs found
Effet de certaines espÚces fongiques sur le développement de la ternissure des grains de riz (Oryza sativa L.)
Sept (7) espĂšces fongiques isolĂ©es Ă partir des lĂ©sions foliaires et des semences de riz (Helminthosporium oryzae, Helminthosporium sativum, Helminthosporium spiciferum, Helminthosporium australiensis, Curvularia lunata, Fusarium moniliforme et Epicoccum nigrum) ont Ă©tĂ© utilisĂ©es pour inoculer les grains de riz des variĂ©tĂ©s Arco et Taibonnet dans le but dâobserver les symptĂŽmes que ces champignons sont capables de provoquer sur ces semences. Trois mois aprĂšs inoculation des grains par les diffĂ©rentes espĂšces fongiques et dans les trois mois qui suivent lâexpĂ©rience, les indices de ternissure et les pourcentages dâaltĂ©ration des grains ont Ă©tĂ© notĂ©s. Les indices de ternissure les plus importants et les pourcentages dâaltĂ©ration des grains les plus Ă©levĂ©s sont induits par Fusarium moniliforme, Curvularia lunata et Helminthosporium oryzae
Computational Complexity of Atomic Chemical Reaction Networks
Informally, a chemical reaction network is "atomic" if each reaction may be
interpreted as the rearrangement of indivisible units of matter. There are
several reasonable definitions formalizing this idea. We investigate the
computational complexity of deciding whether a given network is atomic
according to each of these definitions.
Our first definition, primitive atomic, which requires each reaction to
preserve the total number of atoms, is to shown to be equivalent to mass
conservation. Since it is known that it can be decided in polynomial time
whether a given chemical reaction network is mass-conserving, the equivalence
gives an efficient algorithm to decide primitive atomicity.
Another definition, subset atomic, further requires that all atoms are
species. We show that deciding whether a given network is subset atomic is in
, and the problem "is a network subset atomic with respect to a
given atom set" is strongly -.
A third definition, reachably atomic, studied by Adleman, Gopalkrishnan et
al., further requires that each species has a sequence of reactions splitting
it into its constituent atoms. We show that there is a to decide whether a given network is reachably atomic, improving
upon the result of Adleman et al. that the problem is . We
show that the reachability problem for reachably atomic networks is
-.
Finally, we demonstrate equivalence relationships between our definitions and
some special cases of another existing definition of atomicity due to Gnacadja
Ouidah et son patrimoine
L'étude sur Ouidah, petite ville de la cÎte du Bénin, se divise en trois parties. La premiÚre présente l'histoire de la cité du 18Úme au début du 20Úme siÚcle, les cultes vodouns qui s'y sont développés et le processus d'urbanisation. La 2Úme partie inventorie les lieux patrimoniaux qui renvoient à cette histoire et aux traits culturels de cette société. La 3Úme dresse un diagnostic des actions et des acteurs dans la ville, rappelle les caractéristiques du patrimoine bùti et propose des mesures pour sa conservation et sa valorisatio
Caractérisation phénotypique et génétique du riz africain (Oryza glaberrima Steud) phenotypic and genetic characterization of african rice (oryza glaberrima steud)
The agronomic interest of African rice and the morphological similarities with other species, arouse the necessity to characterize African rice for recovery and conservation. The present study aims primarily to characterize phenotypically and genetically African rice for better exploitation in aid of rice producers and consumers. Indeed, the phenotypic characteristics of the rice accessions examined have been determined in two agronomics systems (upland and irrigated) carried out about 235 accessions of African rice; and afterwards, genetic characterization using a specific marker has been carried. At the end of the analyzes, with regard to the phenotypic characters, 22 O.sativa or interspecific accessions differing morphologically on several descriptors were identified. Genetically, out of 19 profiles revealed on a 935-bp band, 14 confirmed the phenotypic results. This study shows that 221 out of 235 accessions are O. glaberrima rice. These results show that the accessions of different species analyzed were confused during the collection. They also seems to validate the possibility of hybridization between the two rice species in peasant environment. The accessions characterized strengthen the conservation effort of African rice. This collection can be used for future studies, particularly with perspective to selection and running African rice with the possibility to establish a genetic model to facilitate the transfer of useful genes from O.glaberrima to O.sativa, while controlling the reproductive barrier. Thus, it will be easy to better exploit the genetic diversity of the African species of cultivated rice
Mobilise-D insights to estimate real-world walking speed in multiple conditions with a wearable device
This study aimed to validate a wearable deviceâs walking speed estimation pipeline, considering complexity, speed, and walking bout duration. The goal was to provide recommendations on the use of wearable devices for real-world mobility analysis. Participants with Parkinsonâs Disease, Multiple Sclerosis, Proximal Femoral Fracture, Chronic Obstructive Pulmonary Disease, Congestive Heart Failure, and healthy older adults (nâ=â97) were monitored in the laboratory and the real-world (2.5 h), using a lower back wearable device. Two walking speed estimation pipelines were validated across 4408/1298 (2.5 h/laboratory) detected walking bouts, compared to 4620/1365 bouts detected by a multi-sensor reference system. In the laboratory, the mean absolute error (MAE) and mean relative error (MRE) for walking speed estimation ranged from 0.06 to 0.12 m/s and ââ2.1 to 14.4%, with ICCs (Intraclass correlation coefficients) between good (0.79) and excellent (0.91). Real-world MAE ranged from 0.09 to 0.13, MARE from 1.3 to 22.7%, with ICCs indicating moderate (0.57) to good (0.88) agreement. Lower errors were observed for cohorts without major gait impairments, less complex tasks, and longer walking bouts. The analytical pipelines demonstrated moderate to good accuracy in estimating walking speed. Accuracy depended on confounding factors, emphasizing the need for robust technical validation before clinical application.
Trial registration: ISRCTN â 12246987
Performance of the CERN Proton Synchrotron internal dump: numerical simulation studies and comparison with beam measurements
In the framework of the LHC Injector Upgrade project, a newinternal dump for the CERN Proton Synchrotron (PS) ring has beendesigned, installed, and successfully commissioned. This device isdesigned to move rapidly into the beam and stop charged particlesover several thousand turns to provide protection to PS hardwareagainst beam-induced damage. Due to its design, the internal dumpabsorbs only a fraction of the secondary particles shower producedby the beam particles that impinge on it. The performance of thedump should ensure efficient use throughout the PS energy range,i.e. from injection at 2 GeV (kinetic energy) to flat top at26 GeV (total energy). This paper presents comprehensive numericalsimulations that combine advanced beam dynamics and beam-matterinteraction codes to analyse the behaviour of stopped or scatteredparticles. Based on the impacts computed by multi-turn beam dynamicssimulations, detailed shower simulations with FLUKA wereperformed to assess the impact of the radiation field on downstreamequipment, with a particular emphasis on the dose measured by BeamLoss Monitors. The results of these numerical simulations arecompared with the data collected during the routine operation of thePS and its internal dump
Self-consistent numerical evaluation of concrete shielding activation for proton therapy systems:Application to the proton therapy research centre in Charleroi, Belgium
Due to the advancement of proton therapy for cancer treatment, there has been a worldwide increase in the construction of treatment facilities. Therapy centres are often coupled with clinical, biological or material-science research programs. Research activities require proton beams at energies spanning an extensive range with higher beam currents and longer irradiation times than clinical conditions. Additionally, next-generation proton therapy systems are evolving towards more compact designs. In addition to the increased centresâ workloads, reducing the system in size produces a more significant number of secondary particles per unit volume and time. Therefore, the activation level of materials constituting those future proton therapy centres is expected to be higher, increasing the ambient dose and the amount of radioactive waste collected at the end of a centreâs lifetime. These operating conditions pose new challenges for the shielding design and the reduction of the concrete activation. To tackle them, we propose a novel approach to seamlessly simulate all the processes relevant for the evaluation of the concrete shielding activation using, as an illustration, the Ion Beam Applications ProteusÂź One system. A realistic model of the system is developed using Beam Delivery Simulation (BDSIM), a Geant4-based particle tracking code. It allows a single model to simulate primary and secondary particle tracking in the beamline, its surroundings, and all particle-matter interactions. The code system and library database FISPACT-II allows the computation of the shielding activation by solving the rate equations using ENDF-compliant group library data for nuclear reactions, particle-induced or spontaneous fission yields, and radioactive decay. As input, FISPACT-II is provided with the secondary particle fluences scored using the BDSIM Monte Carlo simulations. This approach is applied to the proton therapy research centre of Charleroi, Belgium. Results compare the evolution of the clearance level and the long-lived nuclide concentrations throughout the facility lifetime when using regular concrete or the newly developed Low Activation Concrete (LAC). A comparison with the initial shielding dimensioning has been performed for all the shielding walls to validate the methodology and highlight the clear benefits of integrating LAC inserts in the shielding design. The effectiveness of coupling BDSIM and FISPACT-II gives a glimpse of the possibility of a complete activation study following the actual workloads of the centre, allowing a better assessment of the shielding activation level at any time of the facility lifespa
The early classification of the nutritional value of protein sources by biological tests using two insects found in stored foodstuffs of theTenebrionidae family:Tenebrio molitor L. andTribolium confusum Duval
Rives coloniales : architectures, de Saint-Louis Ă Douala
Ce livre retrace l'histoire des formes et des modĂšles architecturaux qui, depuis la fin du 15Ăšme siĂšcle, pĂ©riode Ă laquelle les Portugais Ă©tablirent leurs premiers comptoirs, jusqu'aux indĂ©pendances des annĂ©es 1950 et 1960, coexistĂšrent et/ou se succĂ©dĂšrent le long de la CĂŽte de l'Afrique de l'Ouest de l'embouchure du fleuve SĂ©nĂ©gal jusqu'Ă Douala, sur les rives du Wouri. L'ouvrage couvre toutes les formes architecturales depuis les bĂątiments prĂ©fabriquĂ©s d'importation jusqu'aux architectures mises en oeuvre par les autochtones en passant par l'architecture religieuse, civile ou militaire, Ă l'exclusion des architectures dites traditionnelles ou strictement vernaculaires. Les impacts auxquels ont Ă©tĂ© soumises ces "rives" sont soulignĂ©es : impacts de la prĂ©sence europĂ©enne - portugaise, hollandaise, anglaise, française, danoise ...- dont les implants architecturaux vont du chĂąteau fort mĂ©diĂ©val Ă l'immeuble de rapport en bĂ©ton prĂ©contraint, impact europĂ©en indirect en provenance du BrĂ©sil vĂ©hiculĂ© par les esclaves affranchis revenus s'installer sur la terre de leurs ancĂȘtres, ou d'AmĂ©rique du Nord avec pour point de chute le LibĂ©ria, influences orientale ou nord-africaine dont le vecteur principal est l'islam, influences intra-africaines avec pour sources le LibĂ©ria ou le Tog