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OLIVEIRA, L. F. S, FRUTUOSO E MELO, P. F, LIMA, J. E. P, and STAL, I. L
- Nuclear engineering and design. 90(1):25-41
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Energy, Énergie, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Installations de production et de conversion d'énergie: énergie électrique, énergie thermique., Installations for energy generation and conversion: thermal and electrical energy., Centrales nucléaires à fission, Fission nuclear power plants, America, South America, Amérique du Sud, Amérique, America del sur, Analyse, Analysis, Arbre événement, Brésil, Brazil, Brasil, Centrale nucléaire, Nuclear power plant, Planta nuclear, Evaluation probabiliste, Programme ordinateur, Computer program, Risque, Risk, Riesgo, Sécurité, Safety, and Securidad
- Abstract
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Description de la méthodologie utilisée dans le programme d'ordinateur d'analyse d'arbres d'événements pour des évaluations probabilistes de risques. Description détaillée de la structure du programme et de ses entrées et sorties. Discussion de quelques limitations de la version actuelle du programme.
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JACKAI, L. E, ATROPO, P. K, and ODEBIYI, J. A
- Crop protection. 8(6):422-428
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Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Coreidae, Déprédateur, Pest, Plaga, Plante légumière, Vegetable crop, Planta leguminosa, Relation animal végétal, Animal plant relation, Relación animal vegetal, Rendement, Yield, Rendimiento, Seuil dégât économique, Economic injury level, Umbral daño económico, Seuil intervention, Treatment threshold, Umbral tratamiento, Surveillance population, Population survey, Vigilancia población, Vigna unguiculata, and Clavigralla tomenta sicollis
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JACKAI, L. E. N, INANG, E. E, and NWOBI, P
- Tropical pest management. 38(1):56-60
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Invertebres, Invertebrates, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte intégrée, Integrated pest control, Angiospermae, Arthropoda, Coreidae, Culture tropicale, Tropical crop, Cultivo tropical, Dicotyledones, Déprédateur, Pest, Plaga, Heteroptera, Insecta, Insecticide, Insecticida, Invertebrata, Leguminosae, Lepidoptera, Légumineuse grain, Grain legume, Leguminosa grano, Meliaceae, Plante pesticide, Pesticide crop, Planta plaguicida, Pyralidae, Spermatophyta, Azadirachta indica, Efficacité traitement, Treatment efficiency, Eficacia tratamiento, Extrait tissulaire, Tissue extract, Extracto tisular, Lutte antidéprédateur, Pest management, Manejo de plagas, Maruca testulalis, Origine végétale, Plant origin, Origen vegetal, Produit naturel, Natural product, Producto natural, Vigna unguiculata, Clavigralla tomentosicollis, Insecticide végétal, and Botanical insecticide
- Abstract
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The insecticidal activity of neem, Azadirachta indica A. Juss., was tested on two major cowpea pests using different concentrations of aqueous extracts, and powders of both neem seed and kernel. The pests were larvae of Maruca testulalis Geyer (Lepidoptera: Pyralidae), the legume pod borer and Clavigralla tomentosicollis Stäl (Hemiptera: Coreidae), the cowpea coreid bug. Ife Brown, an improved local cowpea variety, and IT84S-2246, a breeding line from IITA grain legume programme, were used in the study. Neem proved effective in acting as an insecticide and affected the rates of development of both pests at concentration as low as ca. 9% solution (wt/vol.).
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4. S-phase fraction and survival benefit from adjuvant chemotherapy or radiotherapy of breast cancer [1994]
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STÅL, O, SKOOG, L, RUTQVIST, L. E, CARSTENSEN, J. M, WINGREN, S, SULLIVAN, S, ANDERSSON, C, DUFMATS, M, and NORDENSKJÖLD, B
- British journal of cancer. 70(6):1258-1262
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Medical oncology, Cancérologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Anticancéreux, Antineoplastic agents, Chimiothérapie, Chemotherapy, Anticancéreux, Antineoplastic agent, Anticanceroso, Chimiothérapie, Chemotherapy, Quimioterapia, Cycle cellulaire, Cell cycle, Ciclo celular, Cytométrie flux, Flow cytometry, Citometría flujo, Etude cas, Case study, Estudio caso, Exploration, Exploración, Glande mammaire, Mammary gland, Glándula mamaria, Homme, Human, Hombre, Phase S, S Phase, Fase S, Pronostic, Prognosis, Pronóstico, Préménopause, Premenopause, Premenopausia, Radiothérapie, Radiotherapy, Radioterapia, Traitement adjuvant, Adjuvant treatment, Tratamiento adyuvante, Traitement, Treatment, Tratamiento, Tumeur maligne, Malignant tumor, and Tumor maligno
- Abstract
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Cancer chemotherapy interacts with cell proliferation, but data on the relationship between cancer cell replication and the effect of adjuvant chemotherapy are scarce. We have investigated the S-phase fractions of the primary tumour from premenopausal breast cancer patients who participated in a randomised trial comparing 12 cycles of polychemotherapy (CMF) with post-operative radiotherapy. DNA flow cytometry was performed on frozen tissues from 208 primary breast carcinomas, of which the S-phase fraction was estimated in 176 cases. There was a significantly higher benefit from CMF among patients with a high S-phase fraction (P=0.0033).
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HAAGMANS, B. L, STALS, F. S, VAN DER MEIDE, P. H, BRUGGEMAN, C. A, HORZINEK, M. C, and SCHIJNS, V. E. C. J
- Journal of virology. 68(4):2297-2304
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Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Microbiology, infectious diseases, Microbiologie, maladies infectieuses, Virology, Virologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pathologie infectieuse, Infectious diseases, Viroses, Viral diseases, Viroses expérimentales et modèles, Experimental viral diseases and models, Betaherpesvirinae, Cytokine, Citoquina, Herpesviridae, Infection, Infección, Mammalia, Rodentia, Vertebrata, Virus, Cytomegalovirus, Facteur nécrose tumorale α, Tumor necrosis factor α, Factor necrosis tumoral α, Histopathologie, Histopathology, Histopatología, Immunodépression, Immunosuppression, Inmunodepresión, Modèle animal, Animal model, Modelo animal, Multiplication virus, Virus multiplication, Multiplicación virus, Pathogénie, Pathogenesis, Patogenia, Pathologie expérimentale, Experimental disease, Patología experimental, Rat, Rata, Relation hôte virus, Host virus relation, Relación huesped virus, Spécificité tissu, Tissue specificity, Especificidad tejido, Symptomatologie, Symptomatology, Sintomatología, Virose, Viral disease, and Virosis
- Abstract
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We investigated the role of tumor necrosis factor alpha (TNF-α) in the pathogenesis of rat cytomegalovirus (RCMV) infection. TNF-α levels found in the sera of radiation-immunosuppressed rats in the course of infection (>350 pg/ml) correlated with the development of RCMV disease. Administration of anti-TNF-α antibodies strongly reduced the severity of pneumonia and led to a reduction in virus titers. In immunocompetent rats, anti-TNF-α antibodies also significantly suppressed viral replication. Conversely, administration of TNF-α augmented RCMV replication and aggravated the disease signs. In vitro, TNF-α enhanced RCMV replication in the macrophage, whereas a reduction of viral replication was observed in fibroblasts, indicating that the effect on viral replication is cell type specific.
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HAAGMANS, B. L, VAN DER MEIDE, P. H, STALS, F. S, VAN DER EERTWEGH, A. J. M, CLAASSEN, E, BRUGGEMAN, C. A, HORZINEK, M. C, and SCHIJNS, V. E. C. J
- Journal of virology. 68(4):2305-2312
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Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Microbiology, infectious diseases, Microbiologie, maladies infectieuses, Virology, Virologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Microbiologie, Microbiology, Virologie, Virology, Cycle de développement, interférence, relations hôte-virus, pouvoir pathogène, souches diverses, Replicative cycle, interference, host-virus relations, pathogenicity, miscellaneous strains, Betaherpesvirinae, Cytokine, Citoquina, Herpesviridae, Infection, Infección, Mammalia, Rodentia, Vertebrata, Virus, Activité biologique, Biological activity, Actividad biológica, Cytomegalovirus, In vitro, In vivo, Interféron gamma, Gamma interferon, Interferón gamma, Modèle animal, Animal model, Modelo animal, Multiplication virus, Virus multiplication, Multiplicación virus, Pathologie expérimentale, Experimental disease, Patología experimental, Rat, Rata, Relation hôte virus, Host virus relation, Relación huesped virus, Virose, Viral disease, and Virosis
- Abstract
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The role of gamma interferon (IFN-γ) in the resolution of rat cytomegalovirus (RCMV) infection was investigated. In the spleen, IFN-γ-producing cells reached maximum numbers on day 7 after infection. Prophylactic treatment with high doses of recombinant rat IFN-γ exerted antiviral activity in fibroblasts and protected immunosuppressed rats against a lethal RCMV challenge. Remarkably, in immunocompetent rats, neutralization of endogenous IFN-γ activity significantly reduced the numbers of RCMV antigen-expressing cells in the spleen, the predominant site of viral replication. Moreover, protection of radiation-immunosuppressed infected rats by transferred immune T cells was enhanced by coinjection of IFN-γ neutralizing antibodies.
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STEIN, J, MULLIKEN, J. B, STAL, S, GASSER, D. L, MALCOLM, S, WINTER, R, BLANTON, S. H, AMOS, C, SEEMANOVA, E, and HECHT, J. T
- American journal of human genetics. 57(2):257-272
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Genetics, Génétique, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Otorhinolaryngologie. Stomatologie, Otorhinolaryngology. Stomatology, Face, maxillaires, dents, parodonte: maladies, sémiologie, Facial bones, jaws, teeth, parodontium: diseases, semeiology, Maladies non tumorales, Non tumoral diseases, Biologie moléculaire, Molecular biology, Biología molecular, Cavité buccale pathologie, Oral cavity disease, Cavidad bucal patología, Génétique, Genetics, Genética, Maladie congénitale, Congenital disease, Enfermedad congénita, Malformation, Malformación, Stomatologie, Stomatology, Estomatología, Déterminisme génétique, Genetic inheritance, Determinismo genético, Etude familiale, Family study, Estudio familiar, Fissure congénitale, Cleft, Fisura congenital, Homme, Human, Hombre, Linkage, Ligamiento, Lèvre, Lip, Labio, Palais, Palate, and Paladar
- Abstract
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Nonsyndromic cleft lip with or without cleft palate (CL/P) is a common craniofacial developmental defect. Recent segregation analyses have suggested that major genes play a role in the etiology of CL/P. Linkage to 22 candidate genes was tested in 11 multigenerational families with CL/P, and 21 of these candidates were excluded. APOC2, 19q13.1, which is linked to the proto-oncogene BCL3, gave suggestive evidence for linkage to CL/P. The study was expanded to include a total of 39 multigenerational CLIP families. Linkage was tested in all families, using an anonymous marker, D19S178, and intragenic markers in BCL3 and APOC2. Linkage was tested under two models, autosomal dominant with reduced penetrance and affecteds only. Homogeneity testing on the two-point data gave evidence of heterogeneity at APOC2 under the affecteds-only model. Both models showed evidence of heterogeneity, with 43% of families linked at zero recombination to BCL3 when marker data from BCL3 and APOC2 were included. A maximum multipoint LOD score of 7.00 at BCL3 was found among the 17 families that had posterior probabilities ≥50% in favor of linkage. The transmission disequilibrium test provided additional evidence for linkage with the 3 allele of BCL3 more often transmitted to affected children. These results suggest that BCL3, or a nearby gene, plays a role in the etiology of CLIP in some families.
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8. Effectiveness of the natural enemies of Lantana camara on Guam : A site and seasonal evaluation [1996]
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MUNIAPPAN, R, DENTON, G. R. W, BROWN, J. W, LALI, T. S, PRASAD, U, and SINGH, P
- Entomophaga. 41(2):167-182
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Plantes parasites. Mauvaises herbes, Parasitic plants. Weeds, Malherbologie, Weeds, Lutte biologique et autres méthodes de lutte, Biological control and other methods, Angiospermae, Arthropoda, Dicotyledones, Invertebrata, Spermatophyta, Verbenaceae, Animal auxiliaire, Beneficial animal, Animal benéfico, Efficacité, Efficiency, Eficacia, Insecta, Lutte biologique, Biological control, Lucha biológica, Mauvaise herbe, Weed, Malezas, Modèle, Models, Modelo, Phytophage, Phytophagous, Fitófago, Relation animal végétal, Animal plant relation, Relación animal vegetal, and Lantana camara
- Abstract
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Dans un effort continu pour éradiquer ou au moins, réduire, la présence de Lantana camara L., adventice bien répandue à Guam, un suivi bi-mensuel a été effectué, sur une période de 4 ans et demi, pour étudier l'efficacité des ennemis naturels à affaiblir la plante et à diminuer le nombre de graines viables. Au total, huit agents de lutte biologique ont été recensés. Les insectes s'attaquant aux feuilles sont: Uroplata girardi Pic. (Col. : Chrysomelidae), Teleonemia scrupulosa Stäl (Hem. : Tingidae), Calycomyza lantanae Frick (Dip. : Agromyzidae) et Hypena strigata (F.) (Lep. : Noctuidae). Les papillons de nuit Lantanophaga pusillidactyla (Walker, (Lep. : Pterophoridae), Epinotia lantana (Busck) (Lep. : Tortricidae) et Adoxopheyes melia Clarke (Lep. : Tortricidae) s'attaquent aux fleurs ainsi que T. scrupulosa. E. lantana et Ophomyia lantanae (Froggatt) (Dip. : Agromyzidae) font des dégâts aux fruits. Un modèle empirique de lutte biologique a été établi à partir des données observées. Le modèle a mis en évidence que les 8 auxiliaires empêchent la production ou détruisent 225,9 baies par mètre carré sur une période d'observation de deux semaines. Sur cette même période, la production de fruits non abîmés observée au mètre carré n'est que de 96,1. Ainsi, les auxiliaires réduisent la production potentielle de fruits de 70,1 %. Le modèle a aussi permis d'estimer le rôle tenu par chaque auxiliaire dans la lutte biologique globale contre L. camara à Guam.
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CARLINI, C. R, OLIVEIRA, A. E. A, AZAMBUJA, P, XAVIER, J. FILHO, and WELLS, M. A
- Journal of economic entomology. 90(2):340-348
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte intégrée, Integrated pest control, Angiospermae, Arthropoda, Bruchidae, Coleoptera, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Reduviidae, Spermatophyta, Callosobruchus maculatus, Canavalia ensiformis, Croissance, Growth, Crecimiento, Déprédateur, Pest, Plaga, Emergence, Emergencia, Insecticide, Insecticida, Larve, Larva, Légumineuse grain, Grain legume, Leguminosa grano, Mortalité, Mortality, Mortalidad, Mue, Molt, Muda, Origine végétale, Plant origin, Origen vegetal, Rhodnius prolixus, Toxicité, Toxicity, Toxicidad, Toxine, Toxin, and Toxina
- Abstract
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Canatoxin is a toxic protein isolated from the jackbean, Cananvalia ensiformis. The toxin injected intraperitoneally is lethal for mice and rats; however, it is inactive if given orally. In this study, Manduca sexta (L.) (Lepidoptera), Schistocerca americana (Drury) (Orthoptera), Drosophila melanogaster (L.) (Diptera), Aedes aegypti (L.) (Diptera), Rhodnius prolixus (Stal) (Hemiptera), and Callosobruchus maculatus (F.) (Coleoptera) were fed on can-atoxin-containing diets. No effects were seen in M. sexta, S. americana, D. melanogaster, or A. aegypti. No traces of canatoxin were found in their feces, suggesting that the protein was digested completely by these insects, which characteristically have a trypsin-based digestion. In contrast, canatoxin was lethal for insects displaying cathepsin-based digestion. Thus, for C. maculatus, a diet containing 0.25% wt:wt canatoxin caused complete inhibition of larval growth. When R. prolixus were fed on canatoxin, 2 effects were seen: impairment of water excretion and increased lethality 48-96 h after feeding. The lethal effect of canatoxin in R. prolixus was blocked partially or completely when the digestion of the toxin by R. prolixus midgut enzymes was impaired. The data showed that canatoxin is highly toxic when ingested by some species of insects but not affecting others, probably in correlation with the characteristics of the digestive process of the insect.
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WALSBY, A. E, HAYES, P. K, BOJE, R, and STAL, L. J
- New phytologist. 136(3):407-417
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Plant biology and physiology, Biologie et physiologie végétales, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie microbienne, Microbial ecology, Milieux divers (espace extraatmosphérique, air, eau), Various environments (extraatmospheric space, air, water), Bactérie, Bacteria, Cyanobacteria, Aphanizomenon flosaquae, Croissance, Growth, Crecimiento, Flottabilité, Buoyancy, Flotabilidad, Milieu marin, Marine environment, Medio marino, Photosynthèse, Photosynthesis, Fotosíntesis, Phytoplancton, Phytoplankton, Fitoplancton, Répartition verticale, Vertical distribution, Distribución vertical, and Vésicule gaz
- Abstract
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Observations were made on the vertical distribution of colonies of Aphanizomenon flos-aquae for 9 d at a driftstation east of Bornholm Island in the Baltic Sea. The buoyant colonies were dispersed in the upper layers of the water column during periods of wind-induced mixing but floated up during calm periods. From measurements of the vertical light extinction, surface irradiance and the photosynthesis versus irradiance curve, calculations were made of the changes in the daily integral of photosynthesis with respect to time and depth throughout the water column. From these calculations it is demonstrated that net photosynthesis by the population of Aphanizomenon flos-aquae increased nearly threefold by floating up after a deep mixing event. It is estimated that, averaged over alternating periods of calm and mixing, the buoyancy provided by gas vesicles in this organism will result in a nearly twofold increase in photosynthesis. A quantitative analysis has been made of the relationship of the daily integral of photosynthesis by the Aphanizomenon population with the mean depth of the population in the water column and the daily insolation. The analysis shows that the integral decreases linearly with respect to mean depth.
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CELIS, J.-P, STALS, L, VANCOILLE, E, and MOHRBACHER, H
- Surface engineering. 14(3):205-210
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Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Frottement. Usure, Contact of materials. Friction. Wear, Choix matériau, Material selection, Selección material, Werkstoffwahl, Essai usure, Wear test, Prueba al desgaste, Verschleissversuch, Modélisation, Modeling, Modelización, Méthode étude, Investigation method, Método estudio, Untersuchungsmethode, Propriété mécanique, Mechanical properties, Propiedad mecánica, Revêtement dur, Hard coating, Revestimiento duro, Rugosité, Roughness, Rugosidad, Rauhigkeit, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, Usure, Wear, Desgaste, Verschleiss, Vitesse usure, Wear rate, and Velocidad desgaste
- Abstract
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The present paper describes how in depth analysis and modelling of wear data obtained from uni- and bidirectional wear tests were used to determine criteria for the selection of materials for tribological applications. Different wear modes in unidirectional ball on disc tests were linked to a load to roughness dependence between body and counterbody. The displacement of the ball is described using a particle flux model and the wear rate in bidirectional fretting tests is discussed, including a new concept based on dissipated frictional energy. The merits of the various approaches used to measure wear in tribological systems are also discussed.
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BIJNENS, W, DE WOLF, I, DE CEUNINCK, W, DE SCHEPPER, L, STALS, L. M, MANCA, J, D'HAEN, J, WU, T. D, D'OLIESLAEGER, M, BEYNE, E, KIEBOOMS, R, VANDERZANDE, D, and GELAN, J
- Synthetic metals. 96(2):87-96
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Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs optoélectroniques, Optoelectronic devices, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Domaines d'application, Application fields, Caractéristique temporelle, Time curve, Característica temporal, Caractéristique électrique, Electrical characteristic, Característica eléctrica, Diode électroluminescente, Light emitting diode, Diodo electroluminescente, Effet champ électrique, Electric field effect, Efecto campo eléctrico, Electroluminescence, Electroluminiscencia, Etude expérimentale, Experimental study, Estudio experimental, Mécanisme, Mechanism, Mecanismo, Phénylènevinylène polymère, Phenylenevinylene polymer, Fenilenovinileno polímero, Polymère conjugué, Conjugated polymer, Polímero conjugado, Vieillissement, Ageing, and Envejecimiento
- Abstract
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Polymer light-emitting diodes (PLEDs) made with poly(p-phenylene vinylene) (PPV) using a non-ionic precursor route with indium-tin oxide (ITO) as anode and Al as cathode have been examined during continuous electrical stress in an oxygen-rich atmosphere. Three distinct regions in the time evolution of the equivalent electrical resistance and the light output of PLEDs are identified. Various electrical and analytical measurement results are presented to explain the main failure mechanisms. The most severe degradation mode can be identified as dielectric breakdown, resulting in 'hot spots' and ohmic leakage paths. The inhibition of the ohmic path formation by oxidation under ambient conditions results in a local delamination of the electrode, shrinking the active area of the device. This loss of active area caused by these oxidative burn-outs can clearly be observed by scanning electron microscopy ( SEM) and is consistent with secondary ion mass spectroscopy (SIMS) results. Emission microscopy (EMMI) inspection provides evidence for electric field induced ageing at defects present in the device. These defects are already present in the as-produced samples, e.g. particle impurities, interface roughness and structural weakness (edges of the Al electrodes).
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MOLINA-RUGAMA, A. J, ZANUNCIO, J. C, CECON, P. R, and MENIN, E
- Tropical ecology. 39(2):185-191
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Ecology, Ecologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Animaux, Animals, Protozoa. Invertebrata, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte biologique, Biological control, Arthropoda, Coleoptera, Heteroptera, Insecta, Invertebrata, Pentatomidae, Prédateur, Predator, Depredador, Tenebrionidae, Zone tropicale, Tropical zone, Zona tropical, Fréquence temporelle, Temporal frequency, Frecuencia temporal, Longévité, Longevity, Longevidad, Lutte biologique, Biological control, Lucha biológica, Nutrition, Nutrición, Relation prédateur proie, Predator prey relation, Relación depredador presa, Reproduction, Reproducción, Survie, Survival, Sobrevivencia, Tenebrio molitor, Oviposition, and Podisus rostratis
- Abstract
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Reproduction and longevity of Podisus rostralis (Stål) (Heteroptera: Pentatomidae) females, fed at different intervals were studied in the Núcleo de Biotecnologia Aplicada à Agropecuária' (BIOAGRO), of the Universidade Federal de Viçosa (UFV), in Viçosa, Minas Gerais, Brazil, at 25 ± 2°C, 70 ± 10% R.H. and photophase of 12 hours. Females of P. rostralis were fed with Tenebrio molitor L. (Coleoptera: Tenebrionidae) larva, during 24 hours, every one, two, four, eight and 16 days. An inverse linear effect was found between oviposition period, egg batches/female, total number and number of eggs per day with feeding interval. Daily fed females laid more eggs (199.6) while those fed every 16 days showed lowest number of eggs (45.3). Longevity of P. rostralis was similar in all feeding intervals. Egg oviposition rate was reduced but females of this predator maintained its longevity which give then higher chances to maintain themselves in the ecosystem until occurs better conditions of preys.
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ALBERTANO, P, VIAGGIU, E, and STAL, L. J
- Marine CyanobacteriaBulletin de l'Institut océanographique (Monaco). :217-222
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Ecology, Ecologie, Oceanography, Océanographie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Microbiologie, Microbiology, Bactériologie, Bacteriology, Action d'agents physiques et chimiques sur les bactéries, Action of physical and chemical agents on bacteria, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie microbienne, Microbial ecology, Milieux divers (espace extraatmosphérique, air, eau), Various environments (extraatmospheric space, air, water), Bactérie, Bacteria, Milieu marin, Marine environment, Medio marino, Adaptation, Adaptación, Analyse quantitative, Quantitative analysis, Análisis cuantitativo, Bloom, Caroténoïde, Carotenoid, Carotenoide, Chlorophylle a, Chlorophyll a, Clorofila a, Cyanobacteria, Dynamique population, Population dynamics, Dinámica población, Emission oxygène, Oxygen emission, Emisión oxígeno, Facteur milieu, Environmental factor, Factor medio, Intensité lumineuse, Luminous intensity, Intensidad luminosa, Lumière, Light, Luz, Photosynthèse, Photosynthesis, Fotosíntesis, Pigment photosynthétique, Photosynthetic pigment, Pigmento fotosintético, Variation saisonnière, Seasonal variation, and Variación estacional
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KIEBOOMS, R, ZOJER, E, MARKART, P, RESEL, R, DE SCHEPPER, L, VANDERZANDE, D, GELAN, J, STALS, L, TASCH, S, and LEISING, G
- Proceedings of the International Conference on Science and Technology of Synthetic Metals (ICSM '98), Montpellier, France, 12-18 July 1998. Part II: Conjugated and conducting polymers contd. Molecular materials and assembliesSynthetic metals. 102(1-3)
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Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs optoélectroniques, Optoelectronic devices, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Domaines d'application, and Application fields
- Abstract
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A new class of precursor polymers, as first described by Louwet at al. [1], was used to make organic LEDs. Device properties are relatively independent from the side chain to be eliminated. However introduction of two methyl groups onto the phenyl ring introduces significant changes in absorption, photoluminescence (PL) emission, PL quantum efficiency and electroluminescence spectra. From XRD there is an indication that this effect might be related to a different packing of the polymer chains.
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KOONA, P, OSISANYA, E. O, JACKAI, L. E. N, TAMO, M, TONYE, J, and NGEVE, J. M
- Bulletin of entomological research. 91(6):453-459
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Relation animal végétal, Animal plant relation, Relación animal vegetal, Spermatophyta, Age, Edad, Comparaison interspécifique, Interspecific comparison, Comparación interespecífica, Coreidae, Dégât, Damage, Estrago, Déprédateur, Pest, Plaga, Gousse, Pod, Vaina, Légumineuse grain, Grain legume, Leguminosa grano, Pentatomidae, Position, Posición, and Vigna unguiculata
- Abstract
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Laboratory and screenhouse studies were carried out to assess the relationship between pod age and pod position of cowpea and damage by different pod bug species. The coreids Clavigralla tomentosicollis Stäl and Riptortus dentipes Fabricius caused significant damage to young pods of cultivated genotypes, in contrast to the coreid Anoplocnemis curvipes Fabricius and the pentatomid Aspavia armigera Fabricius which exhibited minor feeding activity. Percent seed damage declined with pod age, the critical stage for pod bug infestation being when pods were about eight days old. Clavigralla tomentosicollis and R. dentipes caused significantly higher damage to pods located within the leaf canopy, thus behaving differently from Anoplocnemis curvipes which showed a distinct preference for pods growing above the leaf canopy. The feeding activity of Aspavia armigera was not affected by the position of pods on the plant. Overall, the study suggests that cowpea genotypes with a short flowering period and pods held above the leaf canopy offer the most promise in the management of pod-sucking pests.
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JACKAI, L. E. N, NOKOE, S, TAYO, B. O, and KOONA, P
- Journal of applied entomology (1986). 125(5):277-286
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Génétique et amélioration des plantes d'intérêt économique, Genetics and breeding of economic plants, Sélection variétale. Amélioration spéciale, objectifs d'amélioration, Varietal selection. Specialized plant breeding, plant breeding aims, Résistance aux organismes nuisibles, Pest resistance, Déprédateurs, Pest animals, Amélioration génétique, Genetic improvement, Enriquecimiento genético, Angiospermae, Arthropoda, Coreidae, Culture tropicale, Tropical crop, Cultivo tropical, Dicotyledones, Déprédateur, Pest, Plaga, Fruit, Fruto, Heteroptera, Insecta, Invertebrata, Leguminosae, Légumineuse grain, Grain legume, Leguminosa grano, Plante sauvage, Wild plant, Planta salvaje, Spermatophyta, Comparaison interspécifique, Interspecific comparison, Comparación interespecífica, Cultivar, Dégât, Damage, Estrago, Effet dimensionnel, Size effect, Efecto dimensional, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Gousse, Pod, Vaina, Graine, Seeds, Semillas, Infestation, Infestación, Lignée sélection, Breeding line, Línea selección, Mécanisme défense, Defense mechanism, Mecanismo defensa, Ressource génétique, Genetic resource, Recurso genético, Résistance insecte, Insect resistance, Resistencia insecto, Trichome, Tricoma, Vigna unguiculata, Clavigralla tomentosicollis, Péricarpe, Pericarp, and Vigna vexillata
- Abstract
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Studies were conducted in the laboratory to investigate the different components of the resistance of Vigna vexillata A. Richards, TVnu 72, and several cultivars of cultivated Vigna spp. to infestation and damage by the brown cowpea coreid, Clavigralla tomentosicollis Stäl. The main objective was to determine the different roles of the pod wall and seeds, and the relationship between seed size, number, and damage by this insect. Results showed that both the pod wall and seed clearly contribute different components to the resistance of TVnu 72 to C. tomentosicollis. Analysis of the results suggests that the seed defences and the pod wall pericarp may be more important than are trichomes in this resistance. Seed number was found to influence the extent of damage in a more predictable manner than seed size. However, because both of these traits are generally inversely related and mutually exclusive, their individual effects cannot be completely separated. The implications of these traits in a breeding programme targeted at a specific consumer group are discussed.
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HAENEN, K, MEYKENS, K, NESLADEK, M, KNUYT, G, STALS, L. M, TERAJI, T, KOIZUMI, S, and GHEERAERT, E
- Proceedings of Diamond 2000, the 11th European Conference on Diamond, Diamond-like Materials, Carbon Nanotubes, Nitrides and Silicon CarbideDiamond and related materials. 10(3-7):439-443
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Crystallography, Cristallographie cristallogenèse, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Structure électronique et propriétés électriques des surfaces, interfaces, couches minces et structures de basse dimensionnalité, Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures, Etats électroniques de surface et d'interface, Surface and interface electron states, Niveaux de défauts et d'impureté; états d'énergie d'espèces adsorbées, Impurity and defect levels; energy states of adsorbed species, Addition phosphore, Phosphorus additions, Couche épitaxique, Epitaxial layers, Diamant, Diamonds, Dopage, Doping, Dépôt chimique phase vapeur, CVD, Etat impureté, Impurity states, Etude expérimentale, Experimental study, Interaction impureté phonon, Impurity phonon interaction, Interacción impureza fonón, Ionisation, Ionization, Matériau semiconducteur, Semiconductor materials, Oscillation, Oscillations, Photoconductivité, Photoconductivity, Spectrométrie photothermique, Photothermal spectroscopy, and C
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One year ago we published the first results on the electronic structure of the P-level in 1000 ppm PH3/CH4 doped {111}-oriented n-type diamond films, using the quasi-steady-state photocurrent technique (PC) and photothermal ionization spectroscopy (PTIS). In this work we have extended our measurements at various temperatures (4.2-77.4 K) to samples with various doping levels (100, 500 and 1000 ppm PH3/CH4). This allowed us to obtain more precise results for the electronic structure of the phosphorus defect in homoepitaxial n-type CVD diamond films, making use of the 155 meV LO-phonon to explain the oscillatory photoconductivity. These results are confirmed by the PTIS maxima and Fourier transform infra-red (FTIR) data. In addition we present first measurements on a 2000-ppm doped {100}-oriented sample.
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19. Structure and tribological properties of MoSx coatings prepared by bipolar DC magnetron sputtering [2001]
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WANG, Jihui, LAUWERENS, W, WIEERS, E, STALS, L. M, JIAWEN HE, and CELIS, J. P
- Surface & coatings technology. 139(2-3):143-152
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General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Propriétés physiques non électroniques de couches minces, Physical properties of thin films, nonelectronic, Propriétés mécaniques et acoustiques, Mechanical and acoustical properties, Coefficient frottement, Friction factor, Dépôt physique phase vapeur, Physical vapor deposition, Essai usure, Wear testing, Etude expérimentale, Experimental study, Magnétron, Magnetrons, Microstructure, Molybdène sulfure, Molybdenum sulfides, Propriété mécanique, Mechanical properties, Propriété surface, Surface properties, Revêtement, Coatings, SEM, Tribologie, Tribology, Usure petit débattement, Fretting wear, Desgate pequinio desplazamiento, Usure, and Wear
- Abstract
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MoSx coatings were prepared by bipolar pulse DC (balanced and unbalanced) magnetron-sputtering systems. Deposition parameters, cathode current density, argon pressure, bias voltage and magnetron sputtering conditions, were varied in order to obtain low friction and wear-resistant coatings. Composition and surface morphology were determined by energy dispersive X-rays and scanning electron microscopy, while the structure was investigated by X-ray diffraction. The friction and wear properties were investigated by fretting tests in ambient air of < 10% and 50% relative humidity. On proper selection of the argon pressure and the cathode current density, MoSx coatings characterised by a strong (002) basal plane orientation parallel to the substrate were obtained in a reproducible way. Such coatings deposited under optimised conditions exhibit very good lubricity and high wear-resistance, even in ambient air with a relative humidity of 50%. Conversely, when deposition parameters such as higher argon pressure and larger cathode current density result in the deposition of a MoSx coatings with a needle-like structure and preferential (100) and (110) plane orientations, a lower wear resistance is achieved especially in air of 50% relative humidity. Ion bombardment, achieved by applying a negative voltage bias or unbalanced sputtering conditions, improves the friction and wear performance. Conversely, a positive bias voltage deteriorates the tribological performance of the coatings. Experimental data on the friction and sliding wear resistance for MoSx coatings indicate that the best tribological properties are obtained with low sulfur and featureless MoSx coatings.
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WOLFSTEIN, K, DE BROUWER, J. F. C, and STAL, L. J
- Marine ecology. Progress series (Halstenbek). 245:21-31
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Marine biology, limnology, Biologie marine, limnologie, Ecology, Ecologie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Végétaux et champignons, Plants and fungi, Synécologie, Synecology, Ecosystèmes marins, Sea water ecosystems, Algae, Bacillariophyta, Facteur photique, Light effect, Factor fótico, Heterokontophyta, Milieu marin, Marine environment, Medio marino, Thallophyta, Eclairement énergétique, Irradiance, Aclaramiento energético, Extracellulaire, Extracellular, Extracelular, Photosynthèse, Photosynthesis, Fotosíntesis, Phytobenthos, Fitobentos, Polymère, Polymer, Polímero, Productivité biologique, Biological productivity, Productividad biológica, Cylindrotheca closterium, Extracellular polymeric substances, Microphytobenthos, and P/E curves
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The partitioning of photosynthetically fixed carbon (C) into different fractions of intracellular and extracellular C pools by an axenic culture of Cylindrotheca closterium (Ehrenberg) and a field sample of natural benthic diatoms was studied using short-term incubation with 14C at different irradiances. Hence, excretion was directly dependent on the level of irradiance. During the incubations, a comparable amount of about 70 and 75% of the fixed C, respectively, was excreted by the culture and the field sample. This excreted C was distinguished in 2 operational fractions of attached (closely bound to the cells) and colloidal (soluble) material. In the field sample, the percentage of excreted C decreased at irradiances higher than 300 pmol photons m-2 s-1, but it was constant for the culture over the whole range of different irradiances applied. The percentage of extracellular polymeric substances (EPS) in the attached and colloidal material, as obtained by ethanol precipitation, was constant over the range of the provided irradiances for both samples. Subsamples of natural benthic diatoms were treated with an antibiotic cocktail in order to exclude bacterial activity which resulted in unexpected higher values of incorporated C in the fractions of total C, intracellular C, colloidal C and EPS.
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