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Horticulture, Meliaceae, biology, Insect Science, Melia azedarach, Instar, PEST analysis, Pentatomidae, biology.organism_classification, Brown marmorated stink bug, Hemiptera, Nuisance, and Ecology, Evolution, Behavior and Systematics

Currently, the invasive brown marmorated stink bug, Halyomorpha halys (Stal) (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.

Microbiology (medical), medicine.drug_class, Antibiotics, Cephalosporin, Streptococcus mitis, Microbial Sensitivity Tests, beta-Lactam Resistance, Microbiology, Streptococcal Infections, Prevalence, medicine, Humans, Registries, Netherlands, Carbapenem resistance, biology, business.industry, Streptococcus oralis, General Medicine, biology.organism_classification, Third generation, Anti-Bacterial Agents, Cephalosporins, Infectious Diseases, Carbapenems, business, and ANTIBIOTICS

Physics, Total electron content, Physics::Space Physics, Real-time computing, Monitoring system, Storm, Physical and Theoretical Chemistry, Ionosphere, Space (mathematics), Lightning, Physics::Geophysics, and Remote sensing

The paper describes a space monitoring system for powerful impulsive sources designed for detecting storm fronts and lightning activity, predicting powerful magnetic storms, and analyzing the characteristics of faults in the Earth’s curst. It is shown that onboard apparatus can also be used to detect solar and Galactic ionizing-radiation activity, determine the total electron content in the ionosphere, etc. In conclusion, examples of social-economic problems that can be solved using the impulsive-source monitoring system are presented, and perspectives for the further development of this system are discussed.

inorganic chemicals, Ethylene Glycol, Magnetic Resonance Spectroscopy, Hydrogen, Macromolecular Substances, Supramolecular chemistry, chemistry.chemical_element, Catalysis, chemistry.chemical_compound, Polymer chemistry, Materials Chemistry, Molecular Structure, Hydrogen bond, Circular Dichroism, Metals and Alloys, technology, industry, and agriculture, Hydrogen Bonding, General Chemistry, Reference Standards, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry, Solvents, Ceramics and Composites, Thermodynamics, lipids (amino acids, peptides, and proteins), and Ethylene glycol

Substitution of hydrogen bond directed supramolecular assemblies with ethylene glycol chains leads to a reduction in the association constant in apolar solvents, where the reduction of the association constant is dependent on the length of the aliphatic spacer connecting the hydrogen bonds and the ethylene glycol chain.

Oncology, Cancer Research, medicine.medical_specialty, medicine.medical_treatment, Mammary gland, Breast Neoplasms, S Phase, Breast cancer, Risk Factors, Internal medicine, medicine, Humans, Lymph node, Survival analysis, Retrospective Studies, Chemotherapy, Ploidies, business.industry, DNA, Neoplasm, medicine.disease, Combined Modality Therapy, Survival Analysis, Radiation therapy, Tamoxifen, medicine.anatomical_structure, Receptors, Estrogen, Lymphatic Metastasis, Cancer cell, Female, business, medicine.drug, and Research Article

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). The relative risk of distant recurrence or death in the chemotherapy group as compared with the radiotherapy group was 0.19 for patients whose tumours had an S-phase fraction of 10% or over (95% CI 0.07-0.51) and 1.55 (0.88-2.73) for patients whose tumours showed lower S-phase levels. The interaction was still significant in multivariate analysis (P = 0.0057), including lymph node metastases, tumour size and oestrogen receptor content. We conclude that the benefit from adjuvant chemotherapy compared with radiotherapy is largely confined to patients with highly proliferative tumours.

South American tomato leafminer, predator, Otras Ciencias Biológicas, Biological pest control, Parasitoid, purl.org/becyt/ford/1 [https], Ciencias Biológicas, Toxicology, Lepidoptera genitalia, Ciencias Naturales, biocontrol, purl.org/becyt/ford/1.6 [https], LYCOPERSICON ESCULENTUM, parasitoid, Ecology, Evolution, Behavior and Systematics, Eulophidae, biology, Ecology, biology.organism_classification, Gelechiidae, Lycopersicon esculentum L, Insect Science, Dineulophus phthorimaeae, Tuta absoluta, PEST analysis, Braconidae, and CIENCIAS NATURALES Y EXACTAS

Pest suppression through biological control seeks to maximize the action of the pest's natural enemies with the goal of reducing pesticide use. We present a summary of published studies and original findings on several entomophagous species as biocontrol agents of Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), a key pest of tomato crops in Argentina, with the aim to select potential candidates for its management. Spontaneously occurring T. absoluta egg parasitism was lower than that inflicted by the larval parasitoids Dineulophus phthorimaeae (De Santis, 1983) (Hymenoptera: Eulophidae) and Pseudapanteles dignus (Muesebeck, 1938) (Hymenoptera: Braconidae). These parasitoids exhibit important life history traits in laboratory conditions and produce relevant amounts of T. absoluta mortality in the field. Surveys carried out in Tucumán and Buenos Aires provinces, Argentina, revealed that D. phthorimaeae and P. dignus coexist in tomato and eggplant crops; T. absoluta-P. dignus interaction is also found on other non-cultivated solanaceous species present in horticultural farms. In addition, studies are currently under way to determine the predation ability of Zelus obscuridorsis (Stål, 1860) (Hemiptera: Reduviidae) on both larvae and adults of the pest. Finally, we discuss the prospects for implementing experimental augmentative releases of P. dignus to control the pest, a candidate selected considering various positive biological traits and because of its simple mass production and manipulation compared with other antagonists of T. absoluta.
El control biológico de plagas tiene como premisa maximizar la acción de sus enemigos naturales para reducir el uso de plaguicidas en la agricultura. En este trabajo se reúne información de estudios sobre las especies de entomófagos de Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) más importantes en el cultivo de tomate de la Argentina, con el objetivo de seleccionar candidatos potenciales para el control de esta plaga. Comparativamente, el parasitismo natural de huevos de T. absoluta es más bajo que el provocado por los parasitoides larvales Dineulophus phthorimaeae (de Santis, 1983) (Hymenoptera: Eulophidae) y Pseudapanteles dignus (Muesebeck, 1938) (Hymenoptera: Braconidae). Estos parasitoides exhiben atributos relevantes como agentes de control en estudios de laboratorio y campo. Muestreos realizados en las provincias de Tucumán y Buenos Aires, Argentina, mostraron que D. phthorimaeae y P. dignus coexisten en los cultivos de tomate y de berenjena, y también P. dignus se encuentra en otras solanáceas no cultivadas presentes en los predios hortícolas. Adicionalmente, se están llevando a cabo estudios para determinar la capacidad de depredación de Zelus obscuridorsis (Stål, 1860) (Hemiptera: Reduviidae) sobre larvas y adultos de la plaga. Finalmente, se discute sobre la implementación de liberaciones aumentativas de P. dignus, candidato que reúne varios atributos biológicos positivos como potencial agente de control biológico de la plaga, y cuya cría masiva y manipulación son más simples que las de otros antagonistas.
Facultad de Ciencias Naturales y Museo
Centro de Estudios Parasitológicos y de Vectores

0106 biological sciences, 0301 basic medicine, Integrated pest management, Chemical compound, Paederus fuscipes, media_common.quotation_subject, Insect, Biology, 01 natural sciences, Attraction, Toxicology, 010602 entomology, 03 medical and health sciences, chemistry.chemical_compound, 030104 developmental biology, Behavioral response, chemistry, Insect Science, Cyrtorhinus lividipennis, Nymph, and media_common

Plant essential oils (EOs) and a wide range of chemicals affect insect pests in many ways, such as via stimulatory, deterrent, toxic and hormonal effects. Three different compounds ((E)-β-caryophyllene (E-β-C), D-limonene (D-lime) and trans-2-dodecenol (T-2-D)) were tested against Nilaparvata lugens, Cyrtorhinus lividipennis and Paederus fuscipes, and their behavioral response was assessed. The results showed that on average, more N. lugens nymphs were repelled by E-β-C and T-2-D than by D-lime. More C. lividipennis nymphs were attracted to T-2-D and D-lime than to E-β-C. However, P. fuscipes displayed no significant response to the three chemical compounds. The results also demonstrated that T-2-D has exerted significant repellency against N. lugens and a significant attraction for C. lividipennis, while E-β-C and D-lime have no significant effect on any tested insect. T-2-D was selected and tested in a greenhouse under semi-field conditions, where the observations confirmed the results of the laboratory experiments. From the results, it can be concluded that T-2-D at a concentration of 0.06 g/L is an effective synthetic volatile chemical compound and is the strongest repellent of N. lugens and the strongest attractant for C. lividipennis. This synthetic chemical compound can be used as a pest management tool in rice agroecosystems.

Heteroptera, Male, Life Cycle Stages, Biological Control Agents, Solanum lycopersicum, Predatory Behavior, Animals, Female, Moths, and Pest Control, Biological

Tuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological control is considered as one of the control options. Worldwide more than 160 species of natural enemies are associated with this pest, and an important challenge is to quickly find an effective biocontrol agent from this pool of candidate species. Evaluation criteria for control agents are presented, with the advantages they offer for separating potentially useful natural enemies from less promising ones. Next, an aggregate parameter for ranking agents is proposed: the pest kill rate km. We explain why the predator's intrinsic rate of increase cannot be used for comparing the control potential of predators or parasitoids, while km can be used to compare both types of natural enemies. As an example, kill rates for males, females and both sexes combined of three Neotropical mirid species (Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (Stål)) were determined, taking all life-history data (developmental times, survival rates, total nymphal and adult predation, sex ratios and adult lifespan) into account. Based on the value for the intrinsic rate of increase (rm) for T. absoluta and for the kill rate km of the predators, we predict that all three predators are potentially able to control the pest, because their km values are all higher than the rm of the pest. Using only km values, we conclude that E. varians is the best candidate for control of T. absoluta on tomato, with C. infumatus ranking second and M. basicornis last.

Materials science, Polymers and Plastics, Proline, Polymers, Cyclohexanone, Catalysis, Hydrophobic effect, chemistry.chemical_compound, Molecular recognition, Aldol reaction, Materials Chemistry, Organic chemistry, Aldehydes, Cyclohexanones, Organic Chemistry, Substrate (chemistry), Water, Stereoisomerism, Combinatorial chemistry, Naphthalimides, Spectrometry, Fluorescence, chemistry, Organocatalysis, Functional group, Benzamides, Nanoparticles, and Hydrophobic and Hydrophilic Interactions

Here, a modular approach is reported to introduce a specific function into single-chain polymeric nanoparticles (SCPNs). Hereto, an amphiphilic polymer with pendant benzene-1,3,5-tricarboxamide (BTA) units is mixed with a "free" BTA that contains a functional group, either a fluorescent naphthalimide or a catalytically active l-proline. Taking advantage of hydrophobic interactions and self-recognition properties of the BTA units, the "free" BTAs are captured into the interior of the SCPN in water as evidenced by fluorescence studies. To illustrate that function can be readily introduced using a modular approach, l-proline-based BTAs are incorporated to procure a catalytically active SCPN in water. The aldol reaction between p-nitrobenzaldehyde and cyclohexanone shows good conversions at low catalyst loadings and substrate concentrations, and high stereoselectivities are obtained (de = 91% and ee = 98%). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Physics, Nuclear and High Energy Physics, Astronomy and Astrophysics, Statistical and Nonlinear Physics, Plasma, Electron, Charged particle, Secondary electrons, Electronic, Optical and Magnetic Materials, Ion, Distribution function, Ionization, Cathode ray, Electrical and Electronic Engineering, and Atomic physics

A method of solving the nonsteady kinetic equation of deceleration of electrons is developed in the basis of the application of the multigroup approximation. The electron distribution function in air ionized by nonsteady sources of primary electrons is determined, and the process of avalanche formation of secondary electrons in air is investigated. The time dependence of the emission intensity of air is determined, experimentally and by calculation, in two spectral intervals, one of which includes the lambda = 391.4 nm NS N/sub 2//sup +/ (O, O) band while the other includes the lambda = 337.1 nm 2 PS N/sub 2/ (O, O) band, under the action of a short electron beam with an energy E = 100 keV for different values of the gas pressure. The agreement between theoretical results and experimental data indicates the reliability of the method of solving the nonsteady kinetic equation of electron deceleration proposed in the paper.

Male, Veterinary medicine, Spiroplasma, Argentina, Enzyme-Linked Immunosorbent Assay, Polymerase Chain Reaction, Zea mays, law.invention, Hemiptera, Crop, law, Botany, Animals, Pathogen, Polymerase chain reaction, Plant Diseases, Exitianus obscurinervis, Ecology, biology, Inoculation, fungi, food and beverages, General Medicine, biology.organism_classification, Insect Vectors, Leafhopper, Microscopy, Electron, Insect Science, Vector (epidemiology), and Female

"Corn stunt" caused by the mollicute Spiroplasma kunkelii (Whitcomb) is potentially one of the most severe diseases affecting the corn (Zea mays L.) crop in the Americas, and the leafhopper Dalbulus maidis (DeLong & Wolcott) is considered its most important vector. However, other insects seen quite frequently in corn crops might well be its vectors in Argentina To identify any leafhoppers species other than D. maidis that can transmit S. kunkelii, transmission assays were conducted, using individuals of Exitianus obscurinervis (Stal) collected in field and reared under controlled conditions. S. kunkelii was transmitted to corn plants by E. obscurinervis. The pathogen was transmitted to seven of the 11 plants, which showed characteristic corn stunt symptoms, and the presence of the pathogen was confirmed by DAS-ELISA. The presence of S. kunkelii in the E. obscurinervis individuals used in transmission experiments was confirmed by polymerase chain reaction and electron microscopy. The current study shows the existence of a new experimental vector of S. kunkelii, the leafhopper E. obscurinervis, which acquired spiroplasmas from infected plants and inoculated it to healthy plants.

Male, 0106 biological sciences, Macrolophus basicorni, Biological Control Agent, Kill rate, Engytatus varians, Biological pest control, Macrolophus basicornis, biological control, Moth, TRAÇAS, Wiskundige en Statistische Methoden - Biometris, 010603 evolutionary biology, 01 natural sciences, Predation, Heteroptera, Toxicology, South American tomato moth, Lycopersicon esculentum, Laboratory of Entomology, Population dynamics, Pest Control, Biological, Mathematical and Statistical Methods - Biometris, Predator, Campyloneuropsis infumatus, biology, Animal, Engytatus varian, General Medicine, PE&RC, Laboratorium voor Entomologie, biology.organism_classification, Miridae, natural enemy efficacy, Life Cycle Stage, Campyloneuropsis infumatu, 010602 entomology, Predatory Behavior, Insect Science, natural enemy evaluation criteria, Female, Tuta absoluta, PEST analysis, and Agronomy and Crop Science

Tuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological control is considered as one of the control options. Worldwide more than 160 species of natural enemies are associated with this pest, and an important challenge is to quickly find an effective biocontrol agent from this pool of candidate species. Evaluation criteria for control agents are presented, with the advantages they offer for separating potentially useful natural enemies from less promising ones. Next, an aggregate parameter for ranking agents is proposed: the pest kill rate km. We explain why the predator's intrinsic rate of increase cannot be used for comparing the control potential of predators or parasitoids, while km can be used to compare both types of natural enemies. As an example, kill rates for males, females and both sexes combined of three Neotropical mirid species (Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (Stål)) were determined, taking all life-history data (developmental times, survival rates, total nymphal and adult predation, sex ratios and adult lifespan) into account. Based on the value for the intrinsic rate of increase (rm) for T. absoluta and for the kill rate km of the predators, we predict that all three predators are potentially able to control the pest, because their km values are all higher than the rm of the pest. Using only km values, we conclude that E. varians is the best candidate for control of T. absoluta on tomato, with C. infumatus ranking second and M. basicornis last.

Ecology, business.industry, Euschistus tristigmus, media_common.quotation_subject, fungi, Pest control, Insect, Biology, Ipomoea, biology.organism_classification, Predation, Toxicology, chemistry.chemical_compound, chemistry, Agronomy, Nezara viridula, Insect Science, Parathion methyl, Instar, business, Ecology, Evolution, Behavior and Systematics, and media_common

Aerial applications of methyl parathion applied at rates of 0.28 and 0.56 kg/ha in large field plots were tested for the differential morality responses of the last 4 developmental stages of several stink bug species associated with soybean. Both dosage rates gave effective control for all developmental stages of the species examined except 5th-instar Acrosternum hilare (Say) and 4th- and 5th-instar Euschistus servus (Say). No Podisus maculiventris (Say), a predaceous stink bug, were found in any field 24 h posttreatment; whereas, very little mortality was observed for Edessa bifida (Say), a pentatomid that utilizes Ipomoea spp. as hosts. A topical application technique was used to evaluate dosage-mortality responses of field-collected adults of 7 pentatomid species. In addition, responses were obtained for males females and diapausing adults of Nezara viridula (L.) and 5th-instar N. viridula , A. hilare : and E. servus . Based on μg/insect, P. maculiventris had a significantly lower LD50 than the other species (0.032 μg/insect); whereas, E. bifida had a significantly higher LD50 that was from 12 to 107× above other values. Thyanta pallido-virens (Stal) and Euschistus tristigmus (Say) had mortality responses similar to the other soybean pests. Reproductively active and diapausing adults of N. viridula exhibited Similar responses. The μg/insect LD50 for N. viridula , A. hilare and E. servus 5th instars were higher than their corresponding adults.