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EDGHILL, E. L, STALS, K, ORAM, R. A, SHEPHERD, M. H, HATTERSLEY, A. T, and ELLARD, S
- Diabetic medicine. 30(1):114-117
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Endocrinology, Endocrinologie, Nutrition, obesity, metabolic disorders, Nutrition, obésité, maladies métaboliques, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Vertebres: anatomie et physiologie, organisme dans son ensemble ou etude de plusieurs organes ou systemes, Vertebrates: anatomy and physiology, studies on body, several organs or systems, Alimentation. Comportement alimentaire, Feeding. Feeding behavior, Vertebres: endocrinologie, Vertebrates: endocrinology, Sciences medicales, Medical sciences, Endocrinopathies, Pancréas endocrine. Cellules apud (pathologie), Endocrine pancreas. Apud cells (diseases), Diabète. Anomalie tolérance glucose, Diabetes. Impaired glucose tolerance, Etiopathogénie. Dépistage. Explorations. Résistance tissu cible, Etiopathogenesis. Screening. Investigations. Target tissue resistance, Endocrinopathie, Endocrinopathy, Endocrinopatía, Maladie héréditaire, Genetic disease, Enfermedad hereditaria, Pathologie de l'appareil urinaire, Urinary system disease, Aparato urinario patología, Trouble de la nutrition, Nutrition disorder, Trastorno nutricíon, Diabète MODY, Maturity onset diabetes young, Diabetes MODY, Délétion, Deletion, Deleción, Endocrinologie, Endocrinology, Endocrinología, Etat nutritionnel, Nutritional status, Estado nutricional, Homme, Human, Hombre, Malade, Patient, Enfermo, Maladie métabolique, Metabolic diseases, Metabolismo patología, Nutrition, Nutrición, Néphropathie, Nephropathy, Nefropatía, Obésité, Obesity, Obesidad, Pathologie du rein, Kidney disease, and Riñón patología
- Abstract
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Aims Hepatocyte nuclear factor 1β (HNF1B) mutations cause a syndrome of renal cysts and diabetes, with whole gene deletions accounting for approximately 50% of cases. The severity of the renal phenotype is variable, from enlarged cystic kidneys incompatible with life to normal renal development and function. We investigated the prevalence of HNF1B deletions in patients with diabetes but no known renal disease. Methods We tested 461 patients with familial diabetes diagnosed before 45 years, including 258 probands who met clinical criteria for maturity-onset diabetes of the young (two generations affected and at least one family member diagnosed under 25 years). A fluorescent polymerase chain reaction assay was used to analyse two intragenic polymorphic HNF1B markers and identify heterozygous patients who therefore did not have whole gene deletions. Those patients homozygous for both markers were then tested for an HNF1B deletion using multiplex ligation-dependent probe amplification. Results Heterozygous HNF1B intragenic polymorphisms were identified in 337/461 subjects. Multiplex ligation-dependent probe amplification analysis showed an HNF1B gene deletion in three of the remaining 124 probands, all of whom met the criteria for maturity-onset diabetes of the young. Testing of their relatives identified three additional deletion carriers and ultrasound scanning showed renal developmental abnormalities in three of these six patients. Conclusions We estimate that HNF1B mutations account for < 1% of cases of maturity-onset diabetes of the young. Although HNF1B mutations are a rare cause of diabetes in the absence of known renal disease, a genetic diagnosis of renal cysts and diabetes syndrome is important as it raises the possibility of subclinical renal disease and the 50% risk of renal cysts and diabetes syndrome in the patient's offspring.
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KOONA, P, OSISANYA, E. O, LAJIDE, L, JACKAI, L. E. N, and TAMO, M
- Journal of applied entomology (1986). 127(5):293-298
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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, and Fundamental and applied biological sciences. Psychology
- Abstract
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The effects of secondary metabolites in different Vigna species on the development of Clavigralla tomentosicollis were investigated in an artificial seed system using different fractions of crude pod extracts, while the orientation response of this pod-bug to volatile extracts was studied using a dual-choice olfactometer. Feeding on the neutral fraction extracts, in contrast to the basic and acidic fractions, resulted in significantly higher mortalities, longer total developmental time, and lower growth index of the insects in comparison with controls. All volatile extracts elicited an avoidance reaction by C. tomentosicollis, except the volatile from the susceptible genotype IT84S-2246 which generally attracted as many insects as controls. Extracts from wild Vigna species showed higher activity than those from their cultivated relatives. The present study which has established that most secondary metabolites in cowpea pods were localized in the neutral fraction of the crude extract, could facilitate experiments on the separation and characterization of the toxic factors involved.
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NTONIFOR, N. N and JACKAI, L. E. N
- Journal of applied entomology (1986). 120(7):439-443
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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, Coreidae, Dicotyledones, Déprédateur, Pest, Plaga, Heteroptera, Insecta, Invertebrata, Leguminosae, Légumineuse grain, Grain legume, Leguminosa grano, Relation animal végétal, Animal plant relation, Relación animal vegetal, Spermatophyta, Comportement alimentaire, Feeding behavior, Conducta alimenticia, Comportement déprédateur, Pest behavior, Conducta depredadora, Culture tropicale, Tropical crop, Cultivo tropical, Cycle développement, Life cycle, Ciclo desarrollo, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Glycine max, Hôte substitution, Host substitution, Huesped sustitución, Plante hôte, Host plant, Planta huesped, Survie, Survival, Sobrevivencia, Vigna unguiculata, and Clavigralla tomentosicollis
- Abstract
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Suitability of the pods of cowpea (Vigna unguiculata (L.) Walp) and soybean (Glycine max (L.) Merrill) as food for Clavigralla tomentosicollis was determined in the laboratory using development, food substitution and host switch experiments. On soybean pods, nymphs survived for 8 days and adults for 12 days; on cowpea, all nymphal instars developed into adults and lived for 80-100 days. Teneral adults that were switched from cowpea to soybean lost weight, while adults that were moved from soybean to cowpea gained weight with slight differences between the sexes. The shortest critical survival threshold (duration with at least 50% survival) of adults on cowpea was greater than the longest on soybean. The likelihood of C. tomentosicollis exploiting soybean as a trophic niche in areas of tropical Africa where production of this crop is on the increase and usually contiguous with cowpea production, is discussed.
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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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SCHOTZKO, D. J and O'KEEFFE, L. E
- Journal of economic entomology. 83(4):1333-1337
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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, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Animaux, Animals, Protozoa. Invertebrata, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Déprédateur, Pest, Plaga, Développement, Development, Desarrollo, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Fécondité, Fecundity, Fecundidad, Lens culinaris, Longévité, Longevity, Longevidad, Pentatomidae, Pisum sativum, Plante hôte, Host plant, Planta huesped, Plante légumière, Vegetable crop, Planta leguminosa, Relation animal végétal, Animal plant relation, Relación animal vegetal, Reproduction, Reproducción, and Thyanta pallidovirens
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6. Screening of cowpeas for resistance to Clavigralla tomentosicollis Stål (Hemiptera: Coreidae) [1990]
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JACKAI, L. E. N
- Journal of economic entomology. 83(2):300-305
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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, Africa, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Afrique, Coreidae, Criblage, Screening, Cernido, Déprédateur, Pest, Plaga, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Etude en serre, Greenhouse study, Estudio en invernadero, Etude sur terrain, Field study, Estudio en campo, Lignée sélection, Breeding line, Línea selección, Méthode, Method, Método, Méthodologie, Methodology, Metodología, Nigéria, Nigeria, Origine végétale, Plant origin, Origen vegetal, Plante légumière, Vegetable crop, Planta leguminosa, Relation animal végétal, Animal plant relation, Relación animal vegetal, Résistance insecte, Insect resistance, Resistencia insecto, Sensibilité résistance, Sensitivity resistance, Sensibilidad resistencia, Vigna unguiculata, Pest resistance, Clavigralla tomentosicollis, and Résistance déprédateur
- Abstract
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Description des procédures de criblage destinées à tester la résistance de nouvelles accessions de niébé, et qui peuvent être appliquées pour le criblage rapide de germoplasmes et la séparation des lignées de sélection.
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BAERT, L, UYTTENDAELE, M, STALS, A, VAN COILLIE, E, DIERICK, K, DEBEVERE, J, and BOTTELDOORN, N
- Food Poisoning from Raw Fruit and VegetablesEpidemiology and infection. 137(3):316-325
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Hygiene and public health, epidemiology, occupational medicine, Hygiène et santé publique, épidémiologie, médecine du travail, Microbiology, infectious diseases, Microbiologie, maladies infectieuses, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Microbiologie, Microbiology, Pathologie de l'appareil digestif, Digestive diseases, Aparato digestivo patología, Aliment, Food, Alimento, Epidémiologie, Epidemiology, Epidemiología, Homme, Human, Hombre, Intoxication alimentaire, Food poisoning, Intoxicación alimentaria, Microbiologie, Microbiology, and Microbiología
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The Belgian data for foodborne norovirus (NoV) outbreaks became available for the first time with the introduction of an extraction and detection protocol for NoV in the National Reference Laboratory for foodborne outbreaks in September 2006. In 2007, 10 NoV foodborne outbreaks were reported affecting 392 persons in Belgium. NoV became the most detected agent in foodborne outbreaks followed by Salmonella (eight foodborne outbreaks). The major implicated foods were sandwiches (4/10), where food handlers reported a history of gastroenteritis in two outbreaks. A food handler was implicated in the limited number of Belgian NoV outbreaks which is in accord with internationally recorded data. Forty foodborne and waterborne outbreak events due to NoV, epidemiological and/or laboratory confirmed, from 2000 to 2007 revealed that in 42.5 % of the cases the food handler was responsible for the outbreak, followed by water (27·5%), bivalve shellfish (17·5%) and raspberries (10·0%).
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DE BROUWER, J. F. C, COOKSEY, K. E, WIGGLESWORTH-COOKSEY, B, STAAL, M. J, STAL, L. J, and AVCI, R
- Journal of microbiological methods. 65(3):562-572
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Medical laboratory techniques, Techniques de laboratoire médical, Microbiology, infectious diseases, Microbiologie, maladies infectieuses, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Physiologie vegetale et developpement, Plant physiology and development, Généralités, méthodes, General aspects, methods, Métabolisme, Metabolism, Réserves et sécrétions, pigments, phytochrome, Storage and secretion, pigments, phytochrome, Algae, Heterokontophyta, Thallophyta, Analyse statistique, Statistical analysis, Análisis estadístico, Arbre phylogénétique, Phylogenetic tree, Arbol filogenético, Bacillariophyta, Biofilm, Polymère, Polymer, Polímero, Spectrométrie masse, Mass spectrometry, Espectrometría masa, Sécrétion, Secretion, Secreción, Benthic diatoms, EPS, Extracellular polymeric substances, and ToF-SIMS
- Abstract
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Time of Flight-Secondary Ion Mass Spectrometry (ToF-SIMS) was used to study compositional characteristics of Extracellular Polymeric Substances (EPS) and compared these to characteristics of the EPS-matrix of intact diatom biofilms. Three benthic diatoms species were investigated, Cylindrotheca closterium, Navicula mutica and Nitzschia cf. brevissima. Comparison of the ToF-SIMS spectra of sequentially extracted EPS-fractions by cluster analysis and multidimensional scaling analysis (MDS) indicated that soluble and bound EPS were not distinguishable based on their ion spectra. On the contrary the water insoluble bicarbonate soluble (WIBS)-EPS-fraction formed a distinct cluster showing that this material was compositionally different from the other EPS-fractions. Ion spectra of the EPS-fractions were dissimilar to results obtained from intact biofilms. This suggested that during the extraction procedure, the structure of the EPS irreversibly changed, which alters the fragmentation patterns of the extracellular surface layer. Furthermore, from the examination of the positive ion spectra it was shown that the overall composition of EPS in the intact biofilms was different between diatom species. In spite of these differences, several common peak patterns were shared between different species. This suggests the presence of common structural components in the EPS of these diatoms that may play a role in building the surface EPS-layer.
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9. Distribution of extracellular carbohydrates in three intertidal mudflats in Western Europe [2003]
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DE BROUWER, J. F. C, DE DECKERE, E. M. G. T, and STAL, L. J
- Estuarine, coastal and shelf science (Print). 56(2):313-324
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Marine biology, limnology, Biologie marine, limnologie, Ecology, Ecologie, Environment, Environnement, Oceanography, Océanographie, 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, Synécologie, Synecology, Ecosystèmes saumâtres, Brackish water ecosystems, Milieu saumâtre, Brackish water environment, Medio salobre, Estuaire, Estuaries, Estuario, Etude comparative, Comparative study, Estudio comparativo, Extracellulaire, Extracellular, Extracelular, Glucide, Carbohydrate, Glúcido, Phytobenthos, Fitobentos, Répartition spatiale, Spatial distribution, Distribución espacial, Vasière, Mud flats, Fondo fangoso, Zone intertidale, Intertidal zone, Zona intertidal, Ems-Dollard estuary, Extracellular carbohydrate, Grain size distribution, Humber estuary, Marennes-Oléron Bay, Microphytobenthos, Monosaccharide distribution, and Tidal flats
- Abstract
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In this study, the spatial distribution of two operationally defined extracellular carbohydrate fractions (water- and EDTA-extractable carbohydrates) were examined in three intertidal mudflats in Western Europe (Dollard, the Netherlands; Marennes, France; Humber, UK). The three mudflats were sampled along cross-shore transects and sediment cores were sliced to a depth of 5 cm. In these mudflats diatoms were the dominant component of the microphytobenthos. Carbohydrate content showed little variation with depth but varied along transects within each mudflat. Carbohydrate contents were also significantly different between mudflats and the carbohydrate contents of the stations within a mudflat grouped together resulting in separate clusters. This was also observed when the Marennes mudflat was investigated on a temporal scale. These results suggest that processes that act on the scale of whole mudflats determine the variations in extracellular carbohydrate contents In the surface 0.5 cm of the sediment, water-extractable carbohydrates showed a correlation with both chlorophyll a content and median grain size while EDTA-extractable carbohydrates were only correlated with median grain size. Incubation experiments also showed the importance of microphytobenthos as a source of extracellular carbohydrate especially when subjected to the light. Analyses of the monosaccharide distribution of the carbohydrate fractions revealed that the carbohydrate composition was largely similar between the areas investigated. Structurally. the carbohydrates found in these sediments seem to represent a biorefractory part of the freshly produced carbohydrates that remained after rapid degradation of the mare labile component.
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10. Dinitrogen fixation in the world's oceans [2002]
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KARL, D, MICHAELS, A, BERGMAN, B, CAPONE, D, CARPENTER, E, LETELIER, R, LIPSCHULTZ, F, PAERL, H, SIGMAN, D, and STAL, L
- The nitrogen cycle at regional to global scalesBiogeochemistry (Dordrecht). 57-58:47-98
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Ecology, Ecologie, Geology, Géologie, 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, Article synthèse, Review, Artículo síntesis, Cyanobacteria, Cycle biogéochimique, Biogeochemical cycle, Ciclo biogeoquímico, Diazotrophie, Diazotrophy, Diazotrofía, Fixation azote, Nitrogen fixation, Fijación nitrogeno, Milieu marin, Marine environment, Medio marino, Océan, Ocean, Océano, and Trichodesmium
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The surface water of the marine environment has traditionally been viewed as a nitrogen (N) limited habitat, and this has guided the development of conceptual biogeochemical models focusing largely on the reservoir of nitrate as the critical source of N to sustain primary productivity. However, selected groups of Bacteria, including cyanobacteria, and Archaea can utilize dinitrogen (N2) as an alternative N source. In the marine environment, these microorganisms can have profound effects on net community production processes and can impact the coupling of C-N-P cycles as well as the net oceanic sequestration of atmospheric carbon dioxide. As one component of an integrated 'Nitrogen Transport and Transformations' project, we have begun to re-assess our understanding of (I) the biotic sources and rates of N2 fixation in the world's oceans, (2) the major controls on rates of oceanic N2 fixation, (3) the significance of this N2 fixation for the global carbon cycle and (4) the role of human activities in the alteration of oceanic N2 fixation. Preliminary results indicate that rates of N2 fixation, especially in subtropical and tropical open ocean habitats, have a major role in the global marine N budget. Iron (Fe) bioavailability appears to be an important control and is, therefore, critical in extrapolation to global rates of N2 fixation. Anthropogenic perturbations may alter N2 fixation in coastal environments through habitat destruction and eutrophication, and open ocean N2 fixation may be enhanced by warming and increased stratification of the upper water column. Global anthropogenic and climatic changes may also affect N2 fixation rates, for example by altering dust inputs (i.e. Fe) or by expansion of subtropical boundaries. Some recent estimates of global ocean N2 fixation are in the range of 100-200 Tg N (1-2 x 1014 g N) yr-1, but have large uncertainties. These estimates are nearly an order of magnitude greater than historical, pre-1980 estimates, but approach modern estimates of oceanic denitrification.
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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
- Abstract
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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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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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FABELLAR, L. T and HEINRICHS, E. A
- Environmental entomology. 13(3):832-837
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Ecology, Ecologie, Entomology, Entomologie, 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 appliquée, Applied ecology, Ecotoxicologie, effets biologiques de la pollution, Ecotoxicology, biological effects of pollution, Action de la pollution et effets secondaires des pesticides sur les protozoaires et les invertébrés, Effects of pollution and side effects of pesticides on protozoa and invertebrates, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Généralités, Generalities, Lutte, Control, Angiospermae, Arachnida, Arthropoda, Gramineae, Insecta, Invertebrata, Monocotyledones, Spermatophyta, Acephate, Araneida, Carbophenothion, Cypermethrine, Cyrthorhinus lividipennis, Delphacidae, Deltamethrine, Dose létale 50, Lethal dose 50, Dosis letal 50, Déprédateur, Pest, Effet secondaire, Secondary effect, Efecto secundario, Endosulfan, Entomophage, Entomophagous, Entomofago, Ethylan, Heteroptera, Homoptera, Insecticide, Lycosa pseudoannulata, Microvelia atrolineata, Nilaparvata lugens, Oryza sativa, Osbac, Plante céréalière, Cereal crop, Prédateur, Predator, Predador, Toxicité, Toxicity, and Toxicidad
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STAL, L. J and WALSBY, A. E
- New phytologist. 139(4):665-671
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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, Microbiologie, Microbiology, Bactériologie, Bacteriology, Métabolisme. Enzymes, Metabolism. Enzymes, 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, Activité enzymatique, Enzymatic activity, Actividad enzimática, Bactérie, Bacteria, Cyanobacteria, Enzyme, Enzima, Facteur milieu, Environmental factor, Factor medio, Oxidoreductases, Phytoplancton, Phytoplankton, Fitoplancton, Chlorophylle, Chlorophyll, Clorofila, Eclairement énergétique, Irradiance, Aclaramiento energético, Fixation azote, Nitrogen fixation, Fijación nitrogeno, Flottabilité, Buoyancy, Flotabilidad, Intégration numérique, Numerical integration, Integración numérica, Milieu marin, Marine environment, Medio marino, Modèle mathématique, Mathematical model, Modelo matemático, Nitrogenase, Photosynthèse, Photosynthesis, Fotosíntesis, Variation journalière, Daily variation, Variación diaria, and Aphanizomenon
- Abstract
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Measurements were made of the rates of nitrogenase activity (acetylene reduction) by cyanobacteria collected from the Baltic Sea at 2-h intervals, over a period of 24 h, and incubated under natural light. By relating the chlorophyll-specific rate of N2 fixation (PN) to the mean photon irradiance (I) at different periods, a PN/I curve was constructed. A mathematical description of this relationship was used in the calculation of rates of N2 fixation at different depths and times of day from continuous measurements of surface irradiance and light attenuation. By relating these calculations to the vertical distribution of chlorophyll due to Aphanizomenon flos-aquae, an estimate of the daily integral of N2 fixation by the population of this cyanobacterium was obtained: it varied from 039 to 071 mmol m-2 with a mean value of 053 mmol m-2 over 9 d. Comparisons with similar calculations of the daily integral of photosynthesis over the same period indicated the atomic ratio of N/C fixed is about 022, not very different from the N/C ratio expected for the elemental composition of these cyanobacteria. It is demonstrated that when buoyant gas-vacuolate colonies float up during calm periods the increased irradiance that they experience supports an increased rate of N2 fixation. This increase is less than that seen for carbon fixation because photosynthesis is negated by respiration at low irradiances and is less inhibited at high irradiances.
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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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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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VILLBRANDT, M, STAL, L. J, BERGMAN, B, and KRUMBEIN, W. E
- Botanica acta. 105(2):90-96
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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, Microbiologie, Microbiology, Bactériologie, Bacteriology, Métabolisme. Enzymes, Metabolism. Enzymes, Bactérie, Bacteria, Cyanobacteria, Enzyme, Enzima, Activité enzymatique, Enzymatic activity, Actividad enzimática, Inactivation, Inactivación, Localisation, Localization, Localización, Modification, Modificación, Méthode immunoblotting, Immunoblotting assay, Nitrogenase, Technique immunoor, Immunogold labelling, Técnica inmunooro, Variation diurne, Diurnal variation, Variación diurna, Dinitrogénase réductase, Dinitrogénase, and Oscillatoria limosa
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GOMI, Kenji, SATOH, Masaru, TAKABAYASHI, Junji, OZAWA, Rika, SHINONAGA, Yumi, SANADA, Sachiyo, SASAKI, Katsutomo, MATSUMURA, Masaya, OHASHI, Yuko, KANNO, Hiroo, and AKIMITSU, Kazuya
- Plant journal. 61(1):46-57
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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, Physiologie vegetale et developpement, Plant physiology and development, Angiospermae, Arthropoda, Delphacidae, Enzyme, Enzima, Fulgoromorpha, Gramineae, Homoptera, Insecta, Invertebrata, Monocotyledones, Spermatophyta, Bactérie, Bacteria, Hydroperoxyde, Hydroperoxide, Hidroperóxido, Lyases, Oryza sativa, Résistance induite, Induced resistance, Resistencia inducida, Sogatella furcifera, (2E,6Z)-nonadienal, (E)-2-hexenal, C6 volatiles, hydroperoxide lyase, and induced resistance
- Abstract
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A pre-infestation of the white-backed planthopper (WBPH), Sogatella furcifera Horváth, conferred resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo) in rice (Oryza sativa L.) under both laboratory and field conditions. The infestation of another planthopper species, the brown planthopper (BPH) Nilaparvata lugens Stål, did not significantly reduce the incidence of bacterial blight symptoms. A large-scale screening using a rice DNA microarray and quantitative RT-PCR revealed that WBPH infestation caused the upregulation of more defence-related genes than did BPH infestation. Hydroperoxide lyase 2 (OsHPL2), an enzyme for producing C6 volatiles, was upregulated by WBPH infestation, but not by BPH infestation. One C6 volatile, (E)-2-hexenal, accumulated in rice after WBPH infestation, but not after BPH infestation. A direct application of (E)-2-hexenal to a liquid culture of Xoo inhibited the growth of the bacterium. Furthermore, a vapour treatment of rice plants with (E)-2-hexenal induced resistance to bacterial blight. OsHPL2-overexpressing transgenic rice plants exhibited increased resistance to bacterial blight. Based on these data, we conclude that OsHPL2and its derived (E)-2-hexenal play some role in WBPH-induced resistance in rice.
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BORGES, Miguel, BIRKETT, Michael, ALDRICH, Jeffrey R, OLIVER, James E, CHIBA, Mitsuo, MURATA, Yasuhiro, LAUMANN, Raul A, BARRIGOSSI, José Alexandre, PICKETT, John A, and MORAES, Maria C. B
- Journal of chemical ecology. 32(12):2749-2761
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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, Animaux, Animals, Protozoa. Invertebrata, Arthropoda, Composé sémiochimique, Semiochemicals, Heteroptera, Insecta, Invertebrata, Pentatomidae, Allomone, Alomona, Analyse chimique, Chemical analysis, Análisis químico, Attractif, Attractant, Atractivo, Mâle, Male, Macho, Phéromone sexuelle, Sex pheromone, Feromona sexual, Structure chimique, Chemical structure, Estructura química, Tibraca limbativentris, (1RS, 4RS, 1'5)-4-(1', 5'-dimethylhex-4'-enyl)- 1-methylcyclohex-2-en-1-ol, Semiochemical, allomone, and zingiberenol
- Abstract
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The male-produced sex pheromone from the Brazilian rice stalk stink bug Tibraca limbativentris is reported. Olfactometer bioassays with sexually mature males and females showed that males attracted females, which suggests that males release a sex pheromone. Males were not attracted to either sex, nor were females attractive to conspecific females. Attraction of the females to males was highest at night. The headspace volatiles collected from male and female bugs were analyzed by gas chromatography (GC) and GC-mass spectrometry. Two male-specific compounds were identified as isomers of 1 'S'-zingiberenol, whereas a series of defensive compounds were identified in extracts from both sexes. Zingiberenol has three chiral centers, and the nonselective syntheses used produced two groups of isomers, zingiberenol I containing four isomers, namely (1RS,4RS, 1 'R)-4-( 1 ',5'-dimethylhex-4'-enyl)-1-methylcyclohex-2-en-1-ol, and zingiberenol II containing the other four isomers, namely (1RS,4RS,1'S)-4-(l',5'-dimethylhex-4'-enyl)-1-methylcyclohex-2-en-1-ol. Both groups of stereoisomers were more attractive than hexane controls. The absolute configuration of the insect-produced pheromonal components remains to be elucidated, but the 1'S' stereochemistry was established for at least one of the isomers.
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HEYER, H, STAL, L, and KRUMBEIN, W. E
- Archives of microbiology. 151(6):558-564
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Biotechnology, Biotechnologies, Microbiology, infectious diseases, Microbiologie, maladies infectieuses, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Microbiologie, Microbiology, Bactériologie, Bacteriology, Métabolisme. Enzymes, Metabolism. Enzymes, Bacteria, Bactérie, Acétate, Acetate, Acetato, Anaérobiose, Anaerobiosis, Cyanobacteria, Diholoside, Disaccharide, Diholosido, Ethanol, Etanol, Fermentation, Fermentación, Glycogène, Glycogen, Glicógeno, Lactate, Lactates, Lactato, Métabolisme, Metabolism, Metabolismo, Obscurité, Obscurity, Oscuridad, Sulfure, Sulfides, Sulfuro, Tréhalose, Trehalose, Trehalosa, Fermentation hétérolactique, and Oscillatoria limosa
- Abstract
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The marine nitrogen-fixing cyanobacterium Oscillatoria limosa, strain 23 (Oldenburg) was investigated with respect to its dark anaerobic metabolism. As soon as the cells were incubated anaerobically in the dark, they started to ferment. Glycogen was presumably degraded via the heterolactic fermentative pathway. Glycogen-glucose was degraded to equimolar amounts of lactate, ethanol and carbon dioxide. The disaccharide trehalose, which serves as an osmoprotectant in O. limosa, was also catabolized.
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