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This paper describes blistering of rhenium following 21 keV He-ion irradiation at temperatures between 300 K and 1200 K. Blistering starts at 300 K at a dose of 3×10 ions/cm. The most probable blister diameter varies from 4400 Å at 300 K to 10100 Å at 1200 K. The blister depth τ, the blister diameter φ and the blister height h show a distribution. From the observations one could derive the following relationships: h = 0.35φ; τ=3.43φ. The erosion yield E due to blistering is function of dose E =0.51 atoms/ion at 3×10 ions/cm, E =0.56 atoms/ion at 6×10 ions/cm and E =0.14 atoms/ion at 3×10 ions/cm. The sputtering yield S (21 keV) is estimated to be ∼0.1 atom/ion. The corresponding surface regression is 44Å at 3×10 ions/cm and 1323 Å at 9×10 ions/cm. Surface regression has therefore little influence on the observations at low doses. [ABSTRACT FROM AUTHOR]

POPULATION dynamics and INSECTICIDES

TOXICITY testing and INSECTICIDES

NITROGEN fixation, CYANOBACTERIA, MARINE biology, and MICROBIOLOGY

REPRODUCTION and LONGEVITY

CYANOBACTERIA, NITROGEN fixation, and PHOTOSYNTHESIS

COWPEA, VIGNA, HEMIPTERA, INSECT development, CULTIVARS, DISEASE resistance of plants, and EFFECT of temperature on plants

The growth and development of Clavigralla tomentosicollis Stäl (Hemiptera: Coreidae) and Maruca testulalis Geyer (Lepidoptera: Pyralidae) were studied under laboratory conditions using three cultivated Vigna varieties (IT84E-124, TVu 1890, MRx 10-85S) and one wild variety (TVNu 72) under a range of temperatures: 19°C, 22°C, 25°C, 28°C, 31°C, 34°C, 37°C, 40°C and 43°C. IT84E-124 served as the susceptible and TVNu 72 as the resistant control for both insects. Development time of C. tomentosicollis ranged between 7 days at 37°C to 26 days at 19°C, and decreased with increasing temperature up to an upper temperature threshold of 37°C. The lower temperature threshold for development of C. tomentosicollis was estimated from regression curves to be ca 18.5°C, while the upper threshold was between 34°C and 37°C, the point where nymphal survivorship started to decline. Although 19°C and 22°C gave 90% and 80% survival, respectively, the duration of development at these temperatures was almost twice that reported under field conditions. Adult weights followed an inverse relationship with temperature. Third instar larvae of M. testulalis, obtained after rearing on artificial diet for 7 days prior to feeding on the plants, began to pupate 3 days after infestation at 28, 31 and 34°C. However, adults were obtained only at 22°C and 28°C. Temperatures above 34°C were lethal to the larvae which dried out prior to pupating. The lower temperature threshold determined by regression for pupae was 15.6°-17.8°C on both IT84E-124 and MRx 10-85S. Upper temperature threshold was estimated to be between 28 and 34°C at which no adult emergence was obtained. Female pupae were larger than males and temperature did not appear to influence sex ratio. Thermal requirements, expressed in degree days (DD), increased with temperature for C. tomentosicollis up to 31°C on all varieties. Degree days for M. testulalis pupae were of a lower magnitude than those computed for C. tomentosicollis. Zusammenfassung Entwicklungsprofile zweier Schädlinge an resistenten und empfindlichen Vigna-Genotypen bei konstanten Temperaturen Es wurden Wachstum und Entwicklung von Clavigralla tomentosicollis Stäl (Hem., Coreidae) und Maruca testulalis Geyer (Lep., Pyralidae) unter Laborbedingungen bei Verwendung von 3 kultivierten Vigna-Varietäten (IT84E-124, TVu 1890, MRx 10-85S) und einer Wildwuchs-Varietät (TVNu 72) bei konstanten Temperaturen von 19, 22, 25, 28, 31, 34, 37, 40 und 43°C untersucht. IT84E-124 diente als empfindliche und TVNu 72 als resistente Kontrolle für die beiden Insekten. Die Entwicklungszeit von C. tomentosicollis betrug zwischen 7 Tagen bei 37°C bis 26 Tagen bei 19°C und nahm mit ansteigender Temperatur ab bis zur oberen Temperaturgrenze von 37°C. Die untere Temperaturgrenze ergab sich aus den Regressionskurven zu 18,5°C, die obere lag zwischen 34 und 37°C. Bei letzterer Temperatur begann die Überlebensfähigkeit der Nymphen zu sinken. Obgleich bei 19 und 27°C die Überlebensquoten noch bei 90% und 80% lagen, war die Entwicklungsdauer bei diesen Temperaturen doppelt so lang wie unter Freilandverhältnissen. Die Gewichte der Adulten folgten einer inversen Beziehung zur Temperatur. Die Drittlarven von M. testulalis, die aus der Zucht mit künstlicher Diät 7 Tage früher als bei normaler Pflanzenernährung gewonnen wurden, begannen mit der Verpuppung 3 Tage nach Beeinflussung durch Temperaturen zwischen 28 und 34°C. Jedoch wurden Adulte nur aus Zuchten bei 22 und 28°C gewonnen. Temperaturen über 34°C waren für die Larven letal; diese starben vor der Verpuppung ab. Die untere Temperaturgrenze lag (It. Regressionskurven) zwischen 15,6 und 17,8°C bei beiden Varietäten IT84E-124 und MRx 10-85S. Die obere Temperaturgrenze wurde zwischen 28 und 34°C ermittelt. Die weiblichen Puppen waren größer als die männlichen. Die Temperatur beeinflußte das Geschlechterverhältnis nicht. Die Temperaturbedingungen, ausgedrückt in Tages-Graden (degree days DD) nahmen mit ansteigender Temperatur für C. tomentosicollis bis zu 31°C auf allen Varietäten zu. Die DD-Werte für M. testulalis-Puppen waren geringer als jene von C. tomentosicollis. [ABSTRACT FROM AUTHOR]

TESTING, QUALITY, ELECTRONICS, RELIABILITY in engineering, MATHEMATICAL optimization, and MAINTAINABILITY (Engineering)

A new technique for reliability and quality optimization of electronic components and assemblies, the so called in situ accelerated ageing technique with electrical testing, is presented. This technique is extremely useful for the building-in approach to quality and reliability. First, it can be used to optimize an electronic component or assembly with respect to its quality and reliability performance at a very early stage, i.e. at the design level, at the level of materials selection, and at the level of identifying production techniques and defining production parameters. The typical test time is of the order of 24 hours, which is sufficiently short to allow a design of experiments type approach to quality and reliability optimization. Furthermore, the technique is also very useful for obtaining a deeper understanding of the physico-chemical processes which lead to failure. A number of practical examples where the technique has been successfully applied are discussed. [ABSTRACT FROM AUTHOR]

INSECT host plants, SOYBEAN diseases & pests, COWPEA, COREIDAE, LEGUME diseases & pests, SEED pods, and INSECT food

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. [ABSTRACT FROM AUTHOR]

BIOLOGICAL pest control agents and MODELING (Sculpture)

Canatoxin is a toxic protein isolated from the jackbean, Canavalia ensiformis. The toxin injected intraperitoneally is lethal for mice and rats, however, it is inactive if given orally. In this study, Mandura sexta (L.) (Lepidoptera), Schistocerca americana (Drury) (Orthoptera), Drosophila melanogaster (L.) (Diptera), Aedes aegypti (L.) (Diptera), Rhodnius prolixus (Stal) (Hemiptera), and Callosobruchus maculatus (F.) (Coleoptera) were fed on canatoxin-containing diets. No effects were seen in M. sexta, S. anericana, D. melanogaster or A. aegypti. No traces of canatoxin were found in their feces, suggesting that the protein was digested completely by these insects, which characteristically have a trypsin-based digestion. In contrast, canatoxin was lethal for insects displaying cathepsin-based digestion. Thus, for C.maculatus, a diet containing 0.25% wt:wt canatoxin caused complete inhibition of larval growth. When R. prolixus were fed on canatoxin, 2effects were seen: impairment of water excretion and increased lethality 48--96 h after feeding. The lethal effect of canatoxin in R. prolixus was blocked partially or completely when the digestion of the toxin by R. prolixus midgut enzymes was impaired. The data showed thatcanatoxin is highly toxic when ingested by some species of insects but not affecting others, probably in correlation with the characteristics of the digestive process of the insect. [ABSTRACT FROM AUTHOR]

PLANTING and RICE

Monthly plantings of the rice variety Bouake 189 were made under lowland irrigated conditions, to obtain information on the phenological and seasonal occurrence of pests and diseases on the West African Rice Development Association (WARDA) research farm near Bouake, Cote d'Ivoire. Regular sampling of insect pests and observations on rice yellow mottle virus (RYMV) disease infection throughout the year provided information on the occurrence of RYMV and potential insect vectors. RYMV incidence and grain yields varied depending on planting date, and for a given planting date, varied from one year to another. There was no evidence that RYMV incidence increases in successive seasons under continuous cropping. There was no significant correlation between RYMV incidence and either rainfall or wind speed. Leaf feeding damage by the beetle vector of RYMV, Trichispa sericea Guerin-Meneville (Coleoptera: Chrysomelidae), and percentage RYMV infected plants were severe in the July and August plantings in 1993, but whereas T. sericea was not observed thereafter, RYMV spread continued. The white leafhoppers Cofana spectra (Distant) and C. unimaculata (Signoret) (Hemiptera: Cicadellidae), the green leafhoppers Nephotettix spp. (Hemiptera: Cicadellidae), the spittle bug Locris rubra F. (Hemiptera: Cercopidae), the diopsids Diopsis longicornis Macquart and D. apicalis Dalman (Diptera: Diopsidae), and the grasshopper Oxy hyla Stal (Orthoptera: Acridadae) were the most abundant of the insect pests and had distinct population peaks within a year. However, population abundances were not correlated with RYMV incidence. The variability of RYMV in time and space and the potential role of weeds as alternative hosts for RYMV are discussed. [ABSTRACT FROM AUTHOR]

PREDATION, REPRODUCTION, LONGEVITY, and ECOLOGY

Reproduction and longevity of Podisus restralis (Stil) (Heteroptera:Pentatomidae) females, fed at different intervals were studied in the 'Nucleo de Biotecnologia Aplicada A Agropecuaria' (BIOAGRO), of the'Universidade Federal de Vigosa' (UFV), in Viqosa, Minas Gerais, Brazil, at 25 t 2 deg. C, 70 t 1096 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 and16 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 ofP. rostralis was similar in all feeding intervals. Egg oviposition rate was reduced but females of this predator maintained its longevitywhich give then higher chances to maintain themselves in the ecosystem until occurs better conditions of preys. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether different mammographic categories of interval cancer classified according to findings at the latest screening are associated with different distributions of prognostic factors or with different survival rates. The series consisted of all patients with invasive interval cancer detected from May 1978 to August 1995 (n = 544). The tumours were evaluated with regard to age, radiological category, interval between the latest screen and diagnosis and tumour characteristics at the time of diagnosis. We investigated possible relationships between the survival rate of patients with interval cancer and the interval between the latest screen and diagnosis, tumour characteristics and radiological category of the interval tumours. The study focused on comparison of patients with true interval and missed interval cancer. Women with mammographically occult tumours were younger than those in the other radiological categories. Comparisons of true interval cancers with overlooked or misinterpreted tumours showed equal distributions of age, tumour size, TNM stage and lymph node status. The overlooked or misinterpreted tumours showed significantly higher proportions of grade-I tumours (22 vs 11 %), tumours with low S-phase fraction (SPF; 44 vs 24 %) and oestrogen receptor (ER) positive tumours (72 vs 57 %). However, analyses of survival rates disclosed no clear differences between the two radiological categories. Radiological category and interval between the latest screen and diagnosis were not genuine predictors of the prognosis in patients with invasive interval breast cancer. No certain prognostic difference existed between true interval cancers and overlooked or misinterpreted interval breast cancers, despite higher proportions of grade-I tumours, ER positive tumours and tumours with low SPF in the latter group. [ABSTRACT FROM AUTHOR]

NITROGEN fixation and OCEAN

Explores the ecological aspects of dinitrogen fixation in the world's oceans. Diversity of dinitrogen-fixing microorganisms; Major controls on rates of oceanic dinitrogen fixation; Significance of dinitrogen fixation for the global carbon cycle; Role of human activities in the alteration of oceanic dinitrogen fixation.

AGRICULTURE

Discusses abstracts of articles pertaining to agriculture, featured in the August 2002 issue of the 'Journal of Agricultural Safety and Health.' 'Pesticide Residues in Agricultural Products Monitored in Hyogo Prefecture, Japan, FYs 1995-1999,' by Y. Akiyama, N. Yoshioka and M. Tsuji; 'Pesticide Safety Among Farmworkers: Perceived Risk and Perceived Control As Factors Reflecting Environmental Justice,' by T.A. Arcury.

Striated craniofacial and limb muscles differ in their embryological origin, regulatory program during myogenesis, and innervation. In an attempt to explore the effects of these differences on the striated muscle phenotype in humans, the expression of myosin and myosin-associated thick filament proteins were studied at the single fiber level both in the human jaw-closing masseter muscle and in two limb muscles (biceps brachii and quadriceps femoris muscles). In the masseter, unique combinations of myosin heavy chain (MyHC) and myosin binding protein C (MyBP-C) isoforms were observed at the single fiber level. Compared to the limb muscles, the MyHC isoform expression was more complex in the masseter while the opposite was observed for MyBP-C. In limb muscles, a coordinated expression of three MyHC and three MyBP-C isoforms were observed, i.e., single fibers contained one or two MyHC isoforms, and up to three MyBP-C isoforms. Also, the relative content of the different MyBP-C isoforms correlated with the MyHC isoform expression. In the masseter, on the other hand, up to five different MyHC isoforms could be observed in the same fiber, but only one MyBP-C isoform was identified irrespective MyHC isoform expression. This MyBP-C isoform had a migration rate similar to the slow MyBP-C isoform in limb muscle fibers. In conclusion, a unique myofibrillar protein isoform expression was observed in the human masseter muscle fibers, suggesting significant differences in structural and functional properties between muscle fibers from human masseter and limb muscles. [ABSTRACT FROM AUTHOR]

TONGUE, MORPHOLOGY, COMPARATIVE anatomy, MUSCLES, and MOUTH

The muscle fibre composition of three human intrinsic tongue muscles, the longitudinalis, verticalis and transversus, was investigated in four anterior to posterior regions of the tongue using morphological and enzyme- and immunohistochemical techniques. All three muscles typically contained type I, IIA and IM/IIC fibres. Type I fibres expressed slow myosin heavy chain (MyHC), type II fibres fast MyHC, mainly fast A MyHC, whereas type IM/IIC coexpressed slow and fast MyHCs. Type II fibres were in the majority (60%), but regional differences in proportion and diameter of fibre types were obvious. The anterior region of the tongue contained a predominance of relatively small type II fibres (71%), in contrast to the posterior region which instead showed a majority of larger type I and type IM/IIC fibres (66%). In general, the fibre diameter was larger in the posterior region. This muscle fibre composition of the tongue differs from those of limb, orofacial and masticatory muscles, probably reflecting genotypic as well as phenotypic functional specialization in oral function. The predominance of type II fibres and the regional differences in fibre composition, together with intricate muscle structure, suggest generally fast and flexible actions in positioning and shaping the tongue, during vital tasks such as mastication, swallowing, respiration and speech.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

PLANT chemical defenses, VIGNA, and COREIDAE

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. [ABSTRACT FROM AUTHOR]

ELECTRICAL steel, ELECTRICAL engineering materials, SILICON steel, STEEL, IRON, and STEEL alloys

The results of investigation of the relation between the grain size in the intermediate stages of manufacturing electrical steel and various physical characteristics are given. The investigations are carried out for the purpose of clarifying the possibility of using these characteristics for arranging nondestructive testing of the grain size in the process of steel manufacturing. The paper contains the results of tests performed with the use of the methods of measuring the leakage magnetic fields on the grain boundaries by means of yttrium iron garnet films employed for visualization of the magnetic fields, the Barkhausen effect, the ultrasonic and eddy-current methods, the electromagnetic-acoustic conversion (EMAC) method, and the use of the relation between the grain size and the value of the coercive force. [ABSTRACT FROM AUTHOR]

COWPEA, LEGUMES, DEFOLIATION, PLANT canopies, SEED disinfection, EFFECT of temperature on plants, and PHYSIOLOGICAL effects of temperature

Pottedcowpea, Vigna unguiculata (L.) Walp., plants were used to determine the effects of defoliation and pod position relative to the leaf canopy on infestation and damage by the coreid pod-bugs Clavigralla tomentosicollis Stål and Anoplocnemis curvipes (F.). Temperature measurements were taken within and outside the canopy to determine whether there was a correlation to seed damage. Seed damage decreased significantly with increasing defoliation in plants infested with C. tomentosicollis; an inverse trend was observed with A. curvipes. Temperatures within the canopy increased as the number of leaves decreased. As observed in the defoliation experiment, C. tomentosicollis and A. curvipes reacted differently in a free-choice situation between pods located outside or within the canopy. Significantly higher numbers of C. tomentosicollis concealed themselves within the canopy, where they caused more severe damage to seeds, in comparison with numbers and damage outside the canopy. These trends were reversed for A. curvipes. There was a significant negative correlation between percentage of seed damage and temperature with C. tomentosicollis, and a significant positive correlation with A. curvipes, both in defoliated plants and those with pods distributed outside and within the canopy. Overall, plants with less dense canopy, and long peduncles holding pods outside the canopy showed some resistance to C. tomentosicollis, which is the most damaging pod bug on cowpea. Because such cowpea plants harbor fewer C. tomentosicollis, they are likely to suffer less overall damage from infestation by the complex of pod bugs that occur concurrently in cowpea fields. [ABSTRACT FROM AUTHOR]

INTERTIDAL ecology, SEDIMENTATION & deposition, POLYMERIC composites, DIATOMS, and ALGAE

The sediment-stabilizing effect of benthic diatoms was investigated in a laboratory setting. Axenic cultures of the benthic diatoms Nitzschia cf. brevissima and Cylindrotheca closterium were inoculated in Petri dishes containing sand and incubated under axenic conditions. By ensuring aseptic routines throughout the experiments, interference from other organisms occurring with diatoms in natural photothrophic biofilms was avoided. This allowed the examination of the role of benthic diatoms in sediment stabilization. Increases in the critical erosion shear stress of the sediment were observed in the presence of both diatom taxa relative to sterile sediment. However, N. cf. brevissima was more effective than C. closterium. Values of critical shear stress in the experimental system were in the same range as those observed in natural biofilms, which indicates that diatoms are important agents for biogenic stabilization. Extracellular carbohydrate contents in the microcosms were similar for both diatom species. However, in the presence of N cf. brevissima, extracellular carbohydrate correlated significantly to critical shear stress, explaining up to 80% of the variation, whereas this was not the case for C. closterium. Therefore, it was concluded that the quantity of extracellular polymeric substances (EPS) alone did not explain the biogenic stabilization. Observed adsorption of EPS to sediment particles depended on the relative amount of uronic acids in the exopolymers. Using fluorescently labeled lectins, confocal laser scanning microscopy showed that EPS secretion by N. cf. brevissima resulted in ordered three-dimensional matrix structures. It is suggested that the structuring of EPS plays an prominent role in the process of biostabilization, and that diatoms such as N. cf. brevissima are actively involved in producing the structure of EPS, whereas others such as C. closterium do not do so to the same extent. [ABSTRACT FROM AUTHOR]

BREAST cancer, CANCER in women, CANCER treatment, THERAPEUTICS, TAMOXIFEN, TUMOR growth, and ESTROGEN

Background: Subgroups of breast cancer that have an impaired response to endocrine treatment, despite hormone receptor positivily, 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. [ABSTRACT FROM AUTHOR]

MALONDIALDEHYDE, PEROXIDATION, CRYOBIOLOGY, and ALCOHOLS (Chemical class)

Abstract: Malondialdehyde (MDA) is a widely used marker of oxidative lipid injury whose concentration varies in response to biotic and abiotic stress. Commonly, MDA is quantified as a strong light-absorbing and fluorescing adduct following reaction with thiobarbituric acid (TBA). However, plant tissues in particular contain many compounds that potentially interfere with this reaction and whose concentrations also vary according to the tissue type and stress conditions. As part of our studies into the stress responses of plant tissues, we were interested in developing a rapid, accurate, and robust protocol for MDA analysis using reverse-phased HPLC to avoid these problems with reaction specificity. We demonstrate that a partitioning step into n-butanol during sample preparation is essential and that gradient HPLC analysis is necessary to prevent sample carryover between injections. Furthermore, the starting composition of the mobile phase must be sufficiently hydrophobic to allow direct injection of the n-butanol extracts without peak splitting, tailing, and other artifacts. To minimize analysis times, we used a short, so-called “Rocket” HPLC column and high flow rates. The optimized HPLC separation has a turnaround time of 2.5min per sample. Butanolic extracts of MDA(TBA)2 were stable for at least 48h, and recoveries were linear between 0.38 and 7.5pmol MDA added. Importantly, this procedure proved to be compatible with existing extraction procedures for l-ascorbate and glutathione analysis in different plant species, allowing multiple “stress metabolite” analyses to be carried out on a single tissue extract. [Copyright &y& Elsevier]

CHAGAS' disease, RHODNIUS prolixus, RHODNIUS, CONENOSES, TRYPANOSOMIASIS, LIFE expectancy, LIFE spans, and LIFE (Biology)

Rhodnius prolixus Stål (Reduviidae: Rhodninii) is one of the most important vectors of Chagas disease. As a result of its medical importance, several life history studies have been carried out, but in general with a restricted demographical scope, without assessing the potential tradeoffs in the life history of this insect. In this study, individuals of R. prolixus were kept in two spatially different habitats and several fitness components were measured. The results show that life expectancy in adults is negatively correlated with gross fecundity, indicating a cost of reproduction. Life expectancy is shorter for males and longer for individuals of the same sex in the more complex habitat, where the fitness is lower compared with that of the simpler habitat. [ABSTRACT FROM AUTHOR]

ANIMAL classification, ANIMAL species, IDENTIFICATION of animals, HEMIPTERA, and INSECTS

A male of Tettigonia vitripennis Germar--deposited in the recently rediscovered Germar Hemiptera collection, in the Ivan Franko National University (Ukraine)--is designated as the lectotype and assumed to be erroneously labeled as from Brazil. Homalodisca vitripennis is considered a senior synonym of Tettigonia coagulata syn. nov. and therefore should be used as the scientific name for the glassy-winged sharpshooter, a major vector of the bacterial Pierce's disease of grapes, phony peach disease, plum leaf scald, and oleander leaf scorch in southern United States and northern Mexico. The previously designated type species of Homalodisca Stål, Cicada triquetra F., was found to be mistaken by Stål for C. triangularis F., which is herein fixed as the new type species of this economically important genus. Propetes triquetra comb. nov., previously known only from an unknown locality in South America, is newly recorded from Brazil (Mato Grosso and Pará states). [ABSTRACT FROM AUTHOR]

AGRICULTURAL pests, INSECT anatomy, INSECT physiology, INSECT metamorphosis, INSECT development, and DEVELOPMENTAL biology

The five immature stages of Agonoscelis puberula Stål are described and illustrated; biological notes and a new host plant, Leonotis nepefifolia (L.) are also recorded. [ABSTRACT FROM AUTHOR]

NEEM, CERCOPIDAE, PLANT products, PESTICIDES, PLANT fibers, NYMPHS (Insects), PEST control, HOMOPTERA, and AGRICULTURAL chemicals

Copyright of Journal of Economic Entomology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

SALIVARY glands, DIGESTIVE enzymes, HEMIPTERA, PLANT parasites, and COWPEA

The salivary glands of the cowpea pod-sucking bugs Anoplocnemis curvipes (Fabricius), Clavigralla tomentosicollis Stål, Clavigralla shadabi Dolling, Riptortus dentipes (Fabricius) and Mirperus jaculus (Thunberg) are described and illustrated. Extracts of the glands were assayed for the presence of proteinases, α-amylase, β-amylase and amyloglucosidase. The salivary glands consist of four-lobed principal glands and a tubular accessory gland, and they differ in shape and size among the different species except for the median lobe, which is more or less spherical. The sickle-shaped nature of the posterior lobe reported before for Riptortus linearis (Linnaeus) was also observed in R. dentipes, suggestive of a probable generic characteristic. Anoplocnemis curvipes has the biggest salivary gland, and it is followed by R. dentipes, M. jaculus, C. tomentosicollis and C. shadabi in descending order. Assays of the gland extracts revealed that the four digestive enzymes tested are present in the five coreoid species. Proteinases were preponderant (1.4-94.9 µg/ml), while amylases were detected in traces [(0.5-11.0) x 10-3 µg/ml]. Proteinases may be largely responsible for the feeding damage caused by the coreoid species and their concentration in the glands of the different species correlates well with their known capacity to inflict pod damage and yield reduction in cowpea. Fourth instar nymphs of the different species also had higher concentrations of the digestive enzymes compared with their respective adults; and this correlates with the known ability of the nymphs to cause greater pod damage and yield reduction than adults. [ABSTRACT FROM AUTHOR]

EXPERIMENTAL agriculture, PLANT extracts, COWPEA, CONTROL of agricultural pests & diseases, INSECT pests, and FRUIT

Field experiments were conducted under rain fed conditions in two seasons to test the effectiveness of seven different plant extract mixtures for management of Maruca vitrata (Fab.) and Clavigralla tomentosicollis Stal on cowpea, Vigna unguiculata (L.) Walp. The application of 10:10% w/w of peels of Citrus sinensis + Gmelina arborea leaf extracts, fruits of Capsicum annum + Eucalyptus citriodora leaf extracts, and peels of C. sinensis + Ocimum gratissimum leaf extracts were effective in reducing the incidences of M. vitrata and C.tomentosicollis on flowers and pods of cowpea, respectively. Grain yield was subsequently increased by 3.2 - 3.5× in plots treated with these extract mixtures compared with the control check. Although, the mixtures of peels of C. sinensis + Azadirachta indica leaf, fruits of C. annum + A. indica leaf, and peels of C. sinensis + Vernonia amygdelina leaf extracts were inferior to the extracts mixtures mentioned above in effecting reasonable control of the test insect pests, they were significantly superior to the control check in the two seasons of study. The mixtures of C. sinensis + G. arborea, C. annum + E. citriodora, and C. sinensis + O. gratissimum extracts could play an important role in crop pest management for small holder farms in tropical countries and none of the extract mixtures had any phytotoxic effect on the sprayed plants. [ABSTRACT FROM AUTHOR]

HEMIPTERA, COTTON diseases & pests, and STEREOCHEMISTRY

Research was conducted to evaluate the possibility that a plant bug damaging cotton, Gossypium hirsutum L., in south Texas is actually green mind, Creontiades dillutus Stål, which is the primary plant bug pest of cotton in Australia. Molecular comparisons targeting a fragment of the COl region of mitochondrial DNA were made on Creontiades specimens collected from the Lower Rio Grande Valley of Texas and specimens of green mind and brown mind, C. pacificus Stål, collected from Queensland, Australia. The emerging south Texas cotton pest is neither of the species tested from Australia; rather it is a closely related, possibly indigenous species. Further morphological systematics work is needed to identify the Creontiades species from Texas, and collection of additional specimens from several locations where it is known to occur is ongoing. [ABSTRACT FROM AUTHOR]

ETHYLENE glycol, THERMODYNAMICS, HYDROGEN bonding, SUPRAMOLECULAR chemistry, SOLVENTS, and CHEMICAL reduction

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. [ABSTRACT FROM AUTHOR]

FLUID dynamics, EXCITON theory, ELECTRONIC excitation, NONLINEAR oscillations, and NONLINEAR theories

In the daily life and techniques people all time have interaction with continue media like air or water. In report motion of vibrator with constant air or water flow excitation is observed. In first part of report motion of a vibrator with constant air or water flow velocity excitation is investigated. The main idea is to find out optimal control law for variation of additional area of vibrating object within limits. For solution of the high-speed problem the maximum principle is used. It is shown that optimal control action is on bounds of area limits. Examples of synthesis real mechatronic systems are given. [ABSTRACT FROM AUTHOR]

CROPS

An abstract of the article "Comparative Studies of Cyanobacterial Associations With Crop Plants," by M. Ahmad and colleagues is presented.

BIOCHEMISTRY, NITROGEN, NONMETALS, REVERSE transcriptase, and DNA polymerases

The marine filamentous nonheterocystous nitrogen-fixing cyanobacterium Lyngbya aestuarii (F. K. Mert.) Liebman ex Gomont CCY 9616 was grown under diazotrophic and nondiazotrophic conditions and under an alternating 16:8 light:dark (L:D) regime. Nitrogenase activity appeared just before the onset of the dark period, reaching its maximum 1–2 h in the dark, subsequently decreasing to zero at the beginning of the following light period. Nitrogenase activity was only detected at low levels of O2 (5%) and when the culture was grown in the absence of combined nitrogen. Quantitative reverse transcriptase–PCR (RT-PCR) analysis of one of the structural genes encoding nitrogenase, nifK, showed that the highest levels of transcription preceded the maximum activity of nitrogenase by 2–4 h. nifK transcription was not completely abolished during the remaining time of the 24 h cycle. Even in the presence of nitrate, when nitrogenase activity was undetectable, nifK was still transcribed. The H2-uptake activity seemed to follow the nitrogenase, but the transcription of hupL (gene encoding the large subunit of uptake hydrogenase) preceded the nifK transcription. However, H2-uptake and hupL transcription occurred throughout the 24 h cycle as well as under nondiazotrophic conditions, albeit at much lower levels. The hoxH transcript levels (a structural gene coding for the bidirectional hydrogenase) were similar under diazotrophic or nondiazotrophic conditions but slightly higher during the dark period. All three enzymes investigated are involved in H2 metabolism. It is concluded that the uptake hydrogenase is mainly responsible for H2 uptake. Nevertheless, uptake hydrogenase and nitrogenase do not seem to be coregulated. [ABSTRACT FROM AUTHOR]

BIOLOGICAL pest control, LANTANA camara, PREDICTION theory, BIOCLIMATOLOGY, SPATIAL variation, BIOLOGICAL mathematical modeling, and CHRYSOMELIDAE

Abstract: Understanding the effects of different types and quality of data on bioclimatic modeling predictions is vital to ascertaining the value of existing models, and to improving future models. Bioclimatic models were constructed using the CLIMEX program, using different data types – seasonal dynamics, geographic (overseas) distribution, and a combination of the two – for two biological control agents for the major weed Lantana camara L. in Australia. The models for one agent, Teleonemia scrupulosa Stål (Hemiptera: Tingidae) were based on a higher quality and quantity of data than the models for the other agent, Octotoma scabripennis Guérin-Méneville (Coleoptera: Chrysomelidae). Predictions of the geographic distribution for Australia showed that T. scrupulosa models exhibited greater accuracy with a progressive improvement from seasonal dynamics data, to the model based on overseas distribution, and finally the model combining the two data types. In contrast, O. scabripennis models were of low accuracy, and showed no clear trends across the various model types. These case studies demonstrate the importance of high quality data for developing models, and of supplementing distributional data with species seasonal dynamics data wherever possible. Seasonal dynamics data allows the modeller to focus on the species response to climatic trends, while distributional data enables easier fitting of stress parameters by restricting the species envelope to the described distribution. It is apparent that CLIMEX models based on low quality seasonal dynamics data, together with a small quantity of distributional data, are of minimal value in predicting the spatial extent of species distribution. [Copyright &y& Elsevier]

LYASES, PLANTHOPPERS, RICE, GENES, and XANTHOMONAS

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 OsHPL2 and its derived ( E)-2-hexenal play some role in WBPH-induced resistance in rice. [ABSTRACT FROM AUTHOR]

HOSTS (Biology), STINKBUGS, TOMATOES, and VALLEYS

We investigated the effects of weed hosts on stink bug density and damage ( Euschistus conspersus Uhler and Thyanta pallidovirens Stal), and a nectar bearing plant on natural enemies of stink bugs in the Sacramento Valley of California. Stink bug density and fruit damage were evaluated in processing tomatoes adjacent to weedy and cultivated borders. The density of E. conspersus was significantly greater in tomatoes adjacent to weedy borders in July but not during August/September. Thyanta pallidovirens was less abundant overall (19%), but was found in significantly greater densities adjacent to cultivated borders in July but not in August/September. Mean percent fruit damage by stink bugs was greater adjacent to the weedy border than the cultivated border, but this difference was not significant. Stink bug egg parasitism and generalist predator density were evaluated in fresh market tomatoes adjacent to a sweet alyssum ( Lobularia maritima L.) border and an unplanted control border at three sites. Egg parasitism was significantly greater in the alyssum treatment for the 9–12 September sampling period. Jalysus wickhami VanDuzee (Hemiptera: Berytidae) density was significantly greater in the alyssum treatment in mid-June. No other significant differences in predator populations were detected. Results of these two studies show that habitat manipulations have the potential to reduce densities of E. conspersus in tomato, the first step in developing a farmscape management plan for stink bug control. [ABSTRACT FROM AUTHOR]

COMPARTMENT syndrome, FASCIAE surgery, THERAPEUTICS, ANALYSIS of variance, CAPILLARIES, CHI-squared test, COMPUTER software, EXERCISE, IMMUNOHISTOCHEMISTRY, LEG, LONGITUDINAL method, MICROCIRCULATION, MUSCLES, RESEARCH funding, STRIATED muscle, T-test (Statistics), DATA analysis, CASE-control method, ANALYTICAL chemistry, PATHOLOGY, and DONOR blood supply

There is a paucity of data regarding the pathogenesis of chronic exertional compartment syndrome (CECS), its consequences for the muscles and the effects of treatment with fasciotomy. We analyzed biopsies from the tibialis anterior muscle, from nine patients, obtained during a decompressing fasciotomy and during follow-up 1 year later. Control biopsies were obtained from nine normal subjects. Muscle capillarity, fiber-type composition and fiber area were analyzed with enzyme- and immunohistochemistry and morphometry. At baseline, CECS patients had lower capillary density (273 vs 378 capillaries/mm, P=0.008), lower number of capillaries around muscle fibers (4.5 vs 5.7, P=0.004) and lower number of capillaries in relation to the muscle fiber area (1.1 vs 1.5, P=0.01) compared with normal controls. The fiber-type composition and fiber area did not differ, but focal signs of neuromuscular damage were observed in the CECS samples. At 1-year follow-up after fasciotomy, the fiber area and the number of fibers containing developmental myosin heavy chains were increased, but no enhancement of the capillary network was detected. Thus, morphologically, patients with CECS seemed to have reduced microcirculation capacity. Fasciotomy appeared to trigger a regenerative response in the muscle, however, without any increase in the capillary bed. [ABSTRACT FROM AUTHOR]

RHODNIUS, CONENOSES, CLASSIFICATION of insects, and SPECIES diversity

Tribe Rhodniini includes Rhodnius Stål and Psammolestes Bergroth. Enzymatic and molecular evidence suggest the tribe is monophyletic. Most species are wild, living in palms and bird nests. Traditionally both genera were considered related; nevertheless, molecular studies don't support the Rhodnius monophyly. The goal was to phylogenetically analyze morphometric variation in wing architecture in support of Rhodniini taxonomy and systematics. We photographed 524 wings of five representatives of Rhodniini: Psammolestes arthuri (Pinto) (n = 89), Rhodnius pictipes Stål (n = 21), R. robustus Larrousse (n = 24), R. prolixus Stål (n = 16), and R. neivai Lent (n = 22). As outgroups we studied four representatives of Triatomini: Eratyrus mucronatus Stål (n = 15), Panstrongylus rufotuberculatus (Champion) (n = 45), P. geniculatus (Latreille) (n = 183), and Triatoma maculata (Erichson) (n = 109). Landmark coordinate (x, y) configurations were registered and aligned by Generalized Procrustes Analysis. Covariance Analyses were implemented with proportions of re-classified groups and MANOVA. Then, wing shape variables (confidence intervals from relative warps) and centroid size were cladistically analysed. Statistical analyses of variance found not significant differences in wing isometric size (Kruskal-Wallis) among P. arthuri-R. neivai-R. pictipes; R. robustus-R. prolixus-T. maculata and between P. rufotuberculatus-P. geniculatus. The a posteriori re-classification was perfect in E. mucrunatus 100% and R. pictipes, followed by T. maculata 96%, R. neivai 95%, P arthuri 93.2%; R. prolixus 87.5%, P. geniculatus 87.4%, P. rufotuberculatus 84.4%, and R. robustus 76%. Cladistic analyses under parsimony selected two most parsimonious trees (L=4.461 IC=0.973 and IR=0.979), where the strict consensus showed a monophyletic group with Panstrongylus (rufotuberculatus + geniculatus) and Triatoma + Rhodniini (Rhodinus + Psammolestes), but internally it shows the paraphyly of Rhodnius regarding Psammolestes. The congruence between these results and previous molecular analyses in Rhodniini, reveal the phylogenetic information of our morphometric characters as support to systematic studies, allowing the combination of geometric morphometrics and phylogenetic methods for the first time in this group. [ABSTRACT FROM AUTHOR]

The article highlights a study which examined the characteristics and phylogenetic relationships of the myrocheine stink bug genus Ennius Stål, with special reference to its species Ennius monteironis Distant. The bug's metathoracic scent auricle, female genitalia and male genitalia including inflated aedeagus were investigated. The Ennius species belonged to the Myrochea Stål subclade, under the Myrocheini Stål genus and Kyrtalus genera. The Ennius was found to be predominantly Ethiopian in distribution.

MICROBIAL mats, MICROBIAL aggregation, BIOMARKERS, GENE libraries, RECOMBINANT DNA, and MICROBIAL ecology

The diazotrophic community in microbial mats growing along the shore of the North Sea barrier island Schiermonnikoog (The Netherlands) was studied using microscopy, lipid biomarkers, stable carbon (δC) and nitrogen (δN) isotopes as well as by constructing and analyzing 16S rRNA gene libraries. Depending on their position on the littoral gradient, two types of mats were identified, which showed distinct differences regarding the structure, development and composition of the microbial community. Intertidal microbial mats showed a low species diversity with filamentous non-heterocystous Cyanobacteria providing the main mat structure. In contrast, supratidal microbial mats showed a distinct vertical zonation and a high degree of species diversity. Morphotypes of non-heterocystous Cyanobacteria were recognized as the main structural component in these mats. In addition, unicellular Cyanobacteria were frequently observed, whereas filamentous heterocystous Cyanobacteria occurred only in low numbers. Besides the apparent visual dominance of cyanobacterial morphotpyes, 16S rRNA gene libraries indicated that both microbial mat types also included members of the Proteobacteria and the Cytophaga-Flavobacterium-Bacteroides group as well as diatoms. Bulk δN isotopes of the microbial mats ranged from +6.1‰ in the lower intertidal to −1.2‰ in the supratidal zone, indicating a shift from predominantly nitrate utilization to nitrogen fixation along the littoral gradient. This conclusion was supported by the presence of heterocyst glycolipids, representing lipid biomarkers for nitrogen-fixing heterocystous Cyanobacteria, in supratidal but not in intertidal microbial mats. The availability of combined nitrogen species might thus be a key factor in controlling and regulating the distribution of the diazotrophic microbial community of Schiermonnikoog. [ABSTRACT FROM AUTHOR]

FOOD chains, PREDATORY animals, OXYOPIDAE, COTTON, POPULATION dynamics, and HERBIVORES

Food web studies often examine density and behaviourally mediated effects of predators on herbivores, but are less likely to assess the plant targeted by the herbivore. We conducted a study that incorporated four trophic levels examining the effect of two generalist predators (damsel bugs, Nabis kinbergii Reuter; and lynx spiders, Oxyopes molarius L. Koch) on damage to cotton bolls caused by green mirids ( Creontiades dilutus (Stål)). First we tested whether lynx spiders and damsel bugs could control mirid numbers and cotton boll damage in field cages. We found that in cages containing mirids and only lynx spiders, lynx spiders reduced both mirid numbers and boll damage. However, in cages which contained mirids and both predators (lynx spiders and damsel bugs) only mirid numbers were reduced. To explain the negative effect of damsel bugs on boll damage, we examined the interactions between lynx spiders, damsel bugs and mirids. We found that lynx spiders were better mirid predators than damsel bugs, and that lynx spiders attacked damsel bugs, but not vice versa. Behaviourally, mirids responded to increasing predator pressure regardless of whether the predators were lynx spiders or damsel bugs. However, damsel bugs seemed to alter the behaviour of lynx spiders because in their presence, a higher proportion of lynx spiders moved to the top of the plant, towards the damsel bugs but away from the bolls found lower on the plant. These results suggest that the most likely explanation for the increase in boll damage in the presence of damsel bugs was that lynx spiders moved to the top of the plant in the presence of damsel bugs, which then exposed the bolls lower down on the plant to mirid attack. This work emphasizes the importance of behaviourally mediated effects in food webs extending over four trophic levels. [ABSTRACT FROM AUTHOR]

EXITIANUS, CORN diseases, LEAFHOPPERS, and INSECTS

"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 (Stål) collected in field and reared under controlled conditions. S. kunkelii was transmitted to corn plants by E. obscurirwrvis. 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. [ABSTRACT FROM AUTHOR]

NOROVIRUSES, FOODBORNE diseases, TOMATOES, CUCUMBERS, VIRUS diseases, and PUBLIC health

Abstract: Foodborne viruses, especially noroviruses (NoV), are increasingly reported as the cause of foodborne outbreaks. NoV outbreaks have been reported linked to fresh soft red fruits and leafy greens. Belgium, Canada and France were the first countries to provide data about the prevalence of NoV on fresh produce. In total, 867 samples of leafy greens, 180 samples of fresh soft red fruits and 57 samples of other types of fresh produce (tomatoes, cucumber and fruit salads) were analyzed. Firstly, the NoV detection methodology, including virus and RNA extraction, real-time RT-PCR and quality controls were compared among the three countries. In addition, confirmation and genotyping of the NoV strains was attempted for a subset of NoV positive samples using conventional RT-PCR targeting an alternative region followed by sequencing. Analysis of the process control showed that 653, 179 and 18 samples of the leafy greens, soft red fruits and other fresh produce types were valid for analysis based on the recovery of the process control. NoV was detected by real-time RT-PCR in 28.2% (N=641), 33.3% (N=6) and 50% (N=6) of leafy greens tested in Canada, Belgium and France, respectively. Soft red fruits were found positive by real-time RT-PCR in 34.5% (N=29) and 6.7% (N=150) of the samples tested in Belgium and France, respectively. 55.5% (N=18) of the other fresh produce types, analyzed in Belgium, were found NoV positive by real-time RT-PCR. Conventional RT-PCR resulted in an amplicon of the expected size in 19.5% (52/266) of the NoV positive samples where this assay was attempted. Subsequent sequencing was only successful in 34.6% (18/52) of the suspected amplicons obtained by conventional RT-PCR. From this study, using the described methodology, NoV genomes were frequently detected in fresh produce however sequence confirmation was not successful for the majority of the samples tested. Infection or outbreaks were rarely or not known to be related to the NoV positive samples. With the increase in sensitivity of the detection methodology, there is an increasing concern about the interpretation of positive NoV results by real-time amplification. Strategies to confirm the results by real-time RT-PCR should be developed in analogy with the detection of microbial pathogens in foods. Detection might indicate contact with NoV in the fresh produce chain. Consequently, a potential risk for infection cannot be excluded but the actual risk from RT-PCR NoV positive produce is still unknown. Studies should be designed determining the probability of infection related to the presence or levels of NoV genomic copies. [Copyright &y& Elsevier]

PARENTAL behavior in animals, BELOSTOMA, INSECT evolution, SEXUAL dimorphism in animals, MULTIVARIATE analysis, INSECT adaptation, and INSECTS

Current evidence suggests that sexual size dimorphism (SSD) reflects the male and female adaptation to their different reproductive roles. Belostoma and Lethocerus species, included in Belostomatidae, present different kinds of paternal care. Females of Belostoma Latreille species lay their eggs on the back of males. Males carry, aerate and protect the clutch until hatching, which is critical for offspring survival. Males of Lethocerus Mayr species exhibit some parental care behavior but do not carry the eggs. The genera are nearly related. We studied and compared the SSD patterns of B. oxyurum (Dufour), B. micantulum (Stål), B. elegans (Mayr), B. bifoveolatum Spinola, B. gestroi Montandon and Lethocerus annulipes (Herrich-Schäffer) by means of a multivariate approach to distinguish selection targets in different components of size. Morphometric analysis revealed that SSD patterns vary among traits and that the arrangements are similar in Belostoma species, showing a common trend under resembling selective mechanisms. The widespread SSD trend in insects is that all components of body size are biased towards females, generally related to a fecundity advantage, a pattern now also detected in L. annulipes. We found in Belostoma species that the male has relatively longer middle and hind legs. We propose that SSD in hind legs biased towards males is a selective response for paternal care; they denote a brood-adapted morphology. The middle leg enlargement may be an associated response to maintain effective locomotion. [ABSTRACT FROM AUTHOR]