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BROWN marmorated stink bug, STINKBUGS, PARASITISM, PREDATION, and HEMIPTERA

Stink bugs, including Halyomorpha halys (Stål) and Nezara viridula (L.), are agricultural pests that feed on fruit in a variety of crops. Monitoring predation and parasitism of stink bug egg masses furthers our understanding of potential biological control tactics. However, best practices for laboratory and field assessments of parasitism and predation of egg masses require further attention. We carried out a series of laboratory and field experiments to test whether parasitism and predation for three types of sentinel H. halys egg masses, fresh, frozen, and refrigerated, varied in agricultural commodities. In addition, we asked if predation and parasitism differed between sentinel and naturally occurring H. halys and N. viridula egg masses in soybean. In the laboratory, more H. halys eggs were parasitized by Trissolcus euschisti (Ashmead) (Hymenoptera: Scelionidae) if they were frozen or refrigerated compared to fresh eggs. Similarly, in the field, parasitism was higher for frozen egg masses than fresh. In 2018 and 2019, H. halys natural egg masses had higher parasitism and lower predation compared to sentinel egg masses in soybean. In a paired field test during 2020 and 2021, there was no difference in parasitism between H. halys natural and sentinel eggs, but much higher incidence of parasitism was detected in natural N. viridula egg masses than sentinel eggs. Collecting natural egg masses is the best methodology for field assessment of parasitism of stink bug egg masses; however, if natural egg masses are not easily available, deploying refrigerated sentinel egg masses is a good alternative. [ABSTRACT FROM AUTHOR]

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

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.

MELIACEAE, HOST plants, HEMIPTERA, STINKBUGS, and INSECT antifeedants

Currently, the invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is considered an agricultural and nuisance pest in Georgia. The invasive chinaberry tree, Melia azedarach L. (Meliaceae), commonly grows in dense thickets along roadsides, and in woodlands adjacent to agricultural crops across the southeastern USA. Thus, the objective of this study was to determine the potential of M. azedarach to serve as a host plant of H. halys by examining mortality and feeding of first and second instars on M. azedarach leaves vs. carrot (i.e., a control diet), and documenting presence of H. halys on M. azedarach in woodlands at 2 locations in Georgia where this stink bug has become established. Over all sampling dates and locations, the number of H. halys in chinaberry was very low (0.1 per tree), and only 3 late instars and 1 adult were observed feeding on M. azedarach at 1 field site late in the season. Percentage feeding by second instars of H. halys was lower for individuals given M. azedarach leaves vs. those provided with carrot, most likely indicating that compounds in M. azedarach have an antifeeding effect. In fact, mortality for second instars on M. azedarach leaves was very high, and thus we conclude that M. azedarach is an unsuitable host plant for H. halys. [ABSTRACT FROM AUTHOR]

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

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.

STINKBUGS, BROWN marmorated stink bug, CARBON dioxide, FUMIGATION, ATMOSPHERIC carbon dioxide, HEMIPTERA, and DILUTION

BACKGROUND: The brown marmorated stink bug (BMSB), Halyomorpha halys, has caused significant agricultural damage to numerous hosts, so agricultural producers seek to limit its spread. Where established, BMSB can also cause substantial urban and commercial disturbance, as overwintering adults may seek refuge inside dwellings, covered spaces, vehicles, and consignments. Phytosanitary authorities are most concerned with the importation of 'hitchhiking' adults in this refugia, with certain countries requiring a quarantine treatment to mitigate risk. This study explores fumigation with ethyl formate, applied as 16.7% by mass dilution in carbon dioxide, for control of adult BMSB. RESULTS: The induction of diapause, to simulate overwintering physiology, resulted in 2‐ and 3‐fold increases in the tolerance of adults toward this ethyl formate fumigation at 10 ± 0.5 °C (x¯±2s) lasting for 8 and 12 h, respectively. However, a decreased tolerance (0.7‐fold) of diapausing specimens was observed for a 4‐h duration. Diapausing and nondiapausing adult BMSB can be controlled at the probit 9 level if the headspace concentration of ethyl formate, [EF], in the carbon dioxide mixture is maintained ≥7.68 mg L−1 for 12 h at 10 ± 0.5 °C (x¯±2s). If the duration is shortened to 4 h, [EF] must be maintained ≥14.73 mg L−1 over the course of fumigation. CONCLUSION: The toxicity of ethyl formate in this mixture can be distinct for different physiological states of the same life stage, as evidenced by a ca. 3‐fold increase in the Haber's z parameter for adult BMSB when in diapause. Respective to the physiological state of adults, this study identifies how the applied dose and/or treatment duration can be modulated (i.e. tuned) to ensure adequate toxicological efficacy toward BMSB infesting hosts or refuge at temperatures ca. >10 °C. Published 2022. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Medical oncology, Cancérologie, Medical laboratory techniques, Techniques de laboratoire médical, General medicine general surgery, Médecine et chirurgie générales, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Gynecologie. Andrologie. Obstetrique, Gynecology. Andrology. Obstetrics, Pathologie de la glande mammaire, Mammary gland diseases, Tumeurs, Tumors, Techniques d'exploration et de diagnostic (generalites), Investigative techniques, diagnostic techniques (general aspects), Anatomopathologie. Exploration cytologique. Biochimie. Spectrométries. Méthodes cliniques et paracliniques diverses, Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques, Glande mammaire pathologie, Mammary gland diseases, Glándula mamaria patología, Tumeur maligne, Malignant tumor, Tumor maligno, Adjuvant, Coadyuvante, Anatomopathologie, Anatomic pathology, Anatomía patológica, Essai clinique, Clinical trial, Ensayo clínico, Paramètre, Parameter, Parámetro, Préménopause, Premenopause, Premenopausia, Tamoxifène, Tamoxifene, Tamoxifeno, Cancer sein, Breast cancer, and Cáncer pecho

Background: Subgroups of breast cancer that have an impaired response to endocrine treatment, despite hormone receptor positivity, are still poorly defined. Breast cancer can be subdivided according to standard pathological parameters including histological type, grade, and assessment of proliferation. These parameters are the net result of combinations of genetic alterations effecting tumour behaviour and could potentially reflect subtypes that respond differently to endocrine treatment. Aims: To investigate the usefulness of these parameters as predictors of the response to tamoxifen in premenopausal women with breast cancer. Materials/methods: Clinically established pathological parameters were assessed and related to the tamoxifen response in 500 available tumour specimens from 564 premenopausal patients with breast cancer randomised to either two years of tamoxifen or no treatment with 14 years of follow up. Proliferation was further evaluated by immunohistochemical Ki-67 expression. Results: Oestrogen receptor positive ductal carcinomas responded as expected to tamoxifen, whereas the difference in recurrence free survival between control and tamoxifen treated patients was less apparent in the relatively few lobular carcinomas. For histological grade, there was no obvious difference in treatment response between the groups. The relation between proliferation and tamoxifen response seemed to be more complex, with a clear response in tumours with high and low proliferation, whereas tumours with intermediate proliferation defined by Ki-67 responded more poorly. Conclusions: Clinically established pathology parameters seem to mirror the endocrine treatment response and could potentially be valuable in future treatment decisions for patients with breast cancer.

PULMONARY embolism, CLINICAL prediction rules, NURSING home patients, PREDICTION models, VENOUS thrombosis, THROMBOEMBOLISM, and SYMPTOMS

Aims Risk stratification is used for decisions regarding need for imaging in patients with clinically suspected acute pulmonary embolism (PE). The aim was to develop a clinical prediction model that provides an individualized, accurate probability estimate for the presence of acute PE in patients with suspected disease based on readily available clinical items and D-dimer concentrations. Methods and results An individual patient data meta-analysis was performed based on sixteen cross-sectional or prospective studies with data from 28 305 adult patients with clinically suspected PE from various clinical settings, including primary care, emergency care, hospitalized and nursing home patients. A multilevel logistic regression model was built and validated including ten a priori defined objective candidate predictors to predict objectively confirmed PE at baseline or venous thromboembolism (VTE) during follow-up of 30 to 90 days. Multiple imputation was used for missing data. Backward elimination was performed with a P -value <0.10. Discrimination (c-statistic with 95% confidence intervals [CI] and prediction intervals [PI]) and calibration (outcome:expected [O:E] ratio and calibration plot) were evaluated based on internal-external cross-validation. The accuracy of the model was subsequently compared with algorithms based on the Wells score and D-dimer testing. The final model included age (in years), sex, previous VTE, recent surgery or immobilization, haemoptysis, cancer, clinical signs of deep vein thrombosis, inpatient status, D-dimer (in µg/L), and an interaction term between age and D-dimer. The pooled c-statistic was 0.87 (95% CI, 0.85–0.89; 95% PI, 0.77–0.93) and overall calibration was very good (pooled O:E ratio, 0.99; 95% CI, 0.87–1.14; 95% PI, 0.55–1.79). The model slightly overestimated VTE probability in the lower range of estimated probabilities. Discrimination of the current model in the validation data sets was better than that of the Wells score combined with a D-dimer threshold based on age (c-statistic 0.73; 95% CI, 0.70–0.75) or structured clinical pretest probability (c-statistic 0.79; 95% CI, 0.76–0.81). Conclusion The present model provides an absolute, individualized probability of PE presence in a broad population of patients with suspected PE, with very good discrimination and calibration. Its clinical utility needs to be evaluated in a prospective management or impact study. Registration PROSPERO ID 89366. [ABSTRACT FROM AUTHOR]

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

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.

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), Structure et morphologie de couches minces, Thin film structure and morphology, Structure et morphologie; épaisseur, Structure and morphology; thickness, Diffraction RX, XRD, Dépôt physique phase vapeur, Physical vapor deposition, Etude expérimentale, Experimental study, Frottement, Friction, Magnétron, Magnetrons, Microscopie électronique balayage, Scanning electron microscopy, Microstructure, Molybdène sulfure, Molybdenum sulfides, Propriété mécanique, Mechanical properties, Pulvérisation irradiation, Sputtering, Revêtement, Coatings, Tribologie, Tribology, Usure, and Wear

MoSx coatings were prepared with an unbalanced DC magnetron-sputtering system by varying the DC power mode, target type and liquid nitrogen trap. The composition and surface morphology were examined by energy dispersive X-ray and scanning electron microscopy; structural characterization was determined by X-ray diffraction. The friction and wear properties were evaluated with a fretting tester in dry (< 10% relative humidity) and humid (50% and 90% relative humidity) air. MoSx coatings deposited by simple DC power tended to form rougher surfaces, and had a higher edge orientation of crystallites with worse tribological performance than those by bipolar pulsed DC power. MoSx coatings made by a cold pressed target had a lower deposition rate, and were inclined to form (002) basal orientations parallel to the surface especially at higher argon pressures. The contents of oxygen and carbon in the MoSx coating with the use of liquid nitrogen trap were greatly reduced, but MoSx coatings had lower coefficients of friction and shorter wear life at higher relative humidity. The role of these deposition variables in the formation process is discussed.

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

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.

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

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

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.

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

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.

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

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.

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

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.

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

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

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.

STIMULANTS, LEAFHOPPERS, RICE diseases & pests, BIOLOGICAL assay, and METHANOL

A crude rice extract caused a higher probing response than did the control in the green rice leafhopper, Nephotettix nigropictus. Bioassay-guided separation led to the isolation of four active compounds, isoscoparin 2"-O-glucoside, isoscoparin 2"-O-(6"'-(E)-feruloyl)glucoside, isoscoparin 2"-O-(6"'-(E)-p-coumaroyl)glucoside, and isovitexin 2"-O-(6"'- (E)-feruloyl)glucoside from ODS 40% methanol in water faction. Each of the compounds, or any combination without one of the four compounds, caused weaker probing responses than the crude rice extract. The activity was recovered only when all the compounds were combined. [ABSTRACT FROM AUTHOR]

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

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.

SESAME, BOTANICAL insecticides, INSECTICIDES, CARDIAC glycosides, INSECT mortality, HEMIPTERA, and EXTRACTS

A study was conducted to investigate the insecticidal potency of leaf and stem ethanolic extracts of white sesame (Sesamum indicum L.) on the pod-sucking bug (Clavigralla tomentosicollis Stal.) under laboratory conditions. Four different concentrations of the extracts (5.00, 10.00, 15.00 and 20.00 mg/l) of ethanolic extracts were prepared from the leaf and stem parts of the Sesame plant. Water and Cypermethrin were used as negative and positive controls. Fresh cowpea pods were treated with the various concentrations of the stem and leaf ethanolic extracts and the pod-sucking bugs were introduced into the jars containing the pods. The result obtained revealed significant differences (P≤0.05) in the effect of various concentrations in inducing mortality of the insects at different instars. The extracts were more effective in the first (1st) instars against the pod-sucking bugs. The activity is concentration dependent as it increases with increase in concentration of the extract. However, leaf ethanolic extract proved to be more effective. More so, the percentages of pods infested by the bugs were found to be lower among the 20.00 mg/l treated pods in both stem and leaf ethanolic extracts. The phytochemical result indicated the presence of certain phytochemicals such as alkaloids, carbohydrates, cardiac glycosides, diterpenoids, flavonoids, proteins, saponins, steroids, tannins and triterpenoids that were proved to be vital in the insecticidal activity of the extracts. Thus, the stem and leaf ethanolic extracts of sesame are effective botanical insecticides against C. tomentosicollis especially at 20.00 mg/l of the leaf extract. [ABSTRACT FROM AUTHOR]