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| (1) Paropsis charybdis, the Eucalyptus tortoise beetle, is a serious defoliator of several Eucalyptus species in New Zealand. A series of laboratory experiments demonstrated the growth characteristics of larvae and adults when feeding on E. viminalis at 20°C. These were used as the data bases for quantifying its trophic relationships in terms of dry matter, energy and nitrogen. (2) The four larval stages lasted 4.0, 2.5, 3.0 and 9.5 days. Growth was exponential until the second day of the fourth instar, when the superficially inactive prepupal stage began. The pupal stage lasted 9.5 days. Female beetles started to lay eggs 15 days (av.) after eclosion. (3) Larvae attained a mean maximum dry weight (dwt) of 53.29 mg. Reproductive females weighed 63.40 mg, and males 46.71 mg. (4) The guts and their contents contributed up to 50% of total larval dry weight and 15% of adult dry weight. (5) Studies of the trophic relationships of P. charybdis larvae were based upon budgets whereby consumption (C) equals the sum of production (P), respiretion (R) and egesta (FU). Production was divided into gut-free larval production (P L* ) and exuvia (P EX )+R+FUin J: 3,561.5 = (491.3+43.4) + 284.5 +2,574.9 in mgN: 4.001 = (2.078 + 0.200) +1.657 (no R term) . P = P L* + P EX The derived R term (R c ), calculated as: R c = C - FU - (P = P L* + P EX ) = 34.84 (6) Daily budgets of an average adult, where ΔP AD reflects the change in body weight and P R =reproductive production, were: C =(ΔP AD + P R ) + R +FU in mg dwt: 27.36 = (ΔP +2.25) +R + 14.53 in J: 591.1 = ΔP + 65.4) + 82.0 +362.6 in mgN: 0368 = (ΔP AD + 0.252) + 0.285. The budget assumes that male P R is zero and includes a corrected R term whereby R C =1.43 R M . ΔP AD can be assumed to equal zero over a long term, although fluctuations were apparent during the experimental period. (7) The amount of leaf material removed but not eaten by larvae (NU) was 22.6 mg, 462.4 J or 0.526 mgN. Thus, the total material removed (MR = C +NU) was 194.3 mg, 3978.9 J or 4.527 mgN. NU per day for an average adult was 4.86 mg, 99.5 J or 0.113 mgN. Therefore adults removed 32.33 mg, 659.9 J or 0.751 mgN per day. (8) Ecological efficiencies (energy) of P. charybdis larvae (using P = P L* + P EX and A = assimilation + C - FU ) were: net ecological efficiency (P.A. -1 )=56.8%, gross ecological efficiency (P.C -1 )=15.2%, assimilation efficiency (A.C. -1 )=26.8%, P.R. -1 =121.5%. Adult efficiencies were: P. A. -1 =28.6%, P.C. -1 =11.1%, A.C. -1 =38.7% and P.R. -1 =55.7%. Efficiencies in terms of nitrogen were (larval data followed by adult data in parentheses): P.A. -1 =97.2 (71.4)%, P.C. -1 =56.9 (39.5)% and A.C. -1 =58.6 (55.3)%. (9) Regressions were calculated to link larval length (1) or larval live weight (lwt) and the dry weight of leaf material removed from a tree by that individual so that these results can be readily applied to field studies: logMR = -2.042 + 3.418 log1 logMR = -0.728 + 1.023 log 1wt.

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]

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]

Animals, Antioxidants metabolism, Apoptosis drug effects, Body Weight drug effects, Carbon Tetrachloride antagonists inhibitors, Carcinogens toxicity, Cell Division drug effects, Diet, Diethylnitrosamine toxicity, Iron administration dosage, Iron metabolism, Kupffer Cells drug effects, Kupffer Cells pathology, Liver metabolism, Liver pathology, Liver Neoplasms, Experimental chemically induced, Liver Neoplasms, Experimental pathology, Male, Necrosis, Organ Size drug effects, Rats, Rats, Wistar, Ubiquinone metabolism, Vitamin E metabolism, Carbon Tetrachloride toxicity, Iron pharmacology, Liver drug effects, and Liver Neoplasms, Experimental prevention control

Background/aims: The aim of this study was to investigate if feeding with carbonyl iron would facilitate the development of preneoplastic lesions initiated by diethylnitrosamine (DEN) and promoted by CCl4-induced liver cirrhosis.
Methods: Male Wistar rats were fed a diet with 1.25%-2.5% carbonyl iron for 23 weeks and received intragastric injections of CCl4 (1.0 or 2.0 ml/kg per week) for 13 weeks, followed by one i.p. injection of DEN (200 mg/kg), after which CCl4 was administered for 8 additional weeks. Animals were killed 48 h after the first CCl4 injection to evaluate liver necrosis, 8 weeks later to evaluate fibrosis, and 9 weeks after DEN to determine formation of glutathione S-transferase 7,7 (GST-7,7) positive foci.
Results: Treatment with iron counteracted the increased serum alanine aminotransferase levels and liver necrosis following CCl4 administration. Hepatic levels of reduced Q9 and alpha-tocopherol were elevated in rats treated with CCl4 and decreased in rats treated with iron compared to the controls. Fibrogenesis was not altered by iron treatment. Nine weeks after DEN initiation, the number and volume density of GST-7,7-positive foci in rats treated with CCl4 were significantly increased as compared with controls, but co-treatment with iron inhibited this increase. Apoptotic index was increased in iron-loaded livers, and labelling index (the fraction of S-phase hepatocytes) was decreased by co-treatment with iron in livers exposed to CCl4.
Conclusion: Carbonyl iron depleted hepatic levels of antioxidants, it decreased CCl4-induced necrosis and cell proliferation, it enhanced apoptosis and did not facilitate fibrogenesis. These effects together may explain the suppression of CCl4-induced promotion after DEN initiation exerted by carbonyl iron in the present study.

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.

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]

Antibodies, Monoclonal immunology, Antibody Affinity immunology, Carrier Proteins genetics, Gene Expression, Humans, Immunoglobulin Variable Region immunology, Immunoglobulin Variable Region isolation purification, Immunoglobulin kappa-Chains genetics, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins immunology, Recombinant Fusion Proteins isolation purification, Substrate Specificity genetics, Substrate Specificity immunology, Antibodies, Monoclonal genetics, Antibody Affinity genetics, Gene Library, Immunoglobulin Variable Region genetics, Peptides immunology, and Plant Proteins immunology

The application of recombinant antibodies in plant biology research is limited because plant researchers have minimal access to high-quality phage display libraries. Therefore, we constructed a library of 1.3 x 10(10) clones displaying human single-chain variable fragments (scFvs) that is available to the academic community. The scFvs selected from the library against a diverse set of plant proteins showed moderate to high antigen-binding affinity together with high specificity. Moreover, to optimize an scFv as immunodetection agent, two expression systems that allow efficient production and purification of bivalent scFv-Fc and scFv-CkappaZIP fusion proteins were integrated. We are convinced that this antibody platform will further stimulate applications of recombinant antibodies such as the diagnostic detection or immunomodulation of specific antigens in plants.

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]

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]