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1.
Sex attractants were established for one Brachodidae, three Choreutidae and two Tineidae moth species during field screening tests with (2E,13Z)-octadecadien-1-al, (2E,13Z)-, (3E,13Z)-, (3Z,13Z)-octadecadien-1-ols and their acetates (2E,13Z-18:Ald, 2E,13Z-, 3E,13Z-, 3Z,13Z-18:OH/OAc) as well as of binary mixtures of these compounds in West-Kazakhstan and Lithuania. Males of Brachodes appendiculata were attracted by 3E,13Z-18:OAc, Prochoreutis ultimana and P. myllerana by 2E,13Z-18:OH, Monopis palidella by 2E,13Z-18:Ald and Triaxomera fulvimitrella by binary mixtures of 3Z,13Z-18:OAc with either 3E,13Z-18:OH in the ratio of 5:5 or 3Z,13Z-18:OH in the ratio of 9:1 (v/v). The 3-component mixture composed of 2E,13Z-18:OH, 3Z,13Z-18:OH and 2E,13Z-18:Ald in the ratio 1:1:1 was developed to attract Prochoreutis sehestediana males. Attraction antagonists for B. appendiculata, P. ultimana and M. palidella were shown.  相似文献   
2.
The calling activity of virgin Phyllonorycter junoniella (Z.) females under a cycling thermal regime differed from that under constant temperature in the following ways: the percentage of females calling at the morning activity peak was increased; the morning period of calling activity was prolonged; the total period of calling activity of an individual female was increased; an extra peak of activity occurred at the end of the photophase, and females changed the calling pattern during the active period. We assume that the occurrence of two calling peaks and the extension of the calling period might be adaptive for a Ph. junoniella species with a sex ratio strongly shifted towards females (8:1 females:males), as it could lead to an increased proportion of females mated.  相似文献   
3.
The role of olfactory cues for host search is much less investigated in day‐active butterflies than in their relatives, the nocturnal moths. The goal of this study was to investigate whether host‐plant volatiles from foliar extracts of hop, Humulus lupulus L. (Cannabaceae), evoke electroantennographic (EAG) responses, increase landing rates, and stimulate egg‐laying behavior of gravid Polygonia c‐album L. (Lepidoptera: Nymphalidae) females. Eighty‐nine volatile compounds were detected in a non‐concentrated methanol extract of hop by gas chromatography–mass spectrometry, 11 of which elicited an EAG response. Concentration of the crude extract significantly reduced landing rates on artificial leaves treated with the sample due to loss of volatile compounds, but after landing the oviposition response of gravid females was not affected. A mixture of eight commercially available EAG‐active volatiles increased the landing rate of gravid females to their source but did not act as oviposition stimulants. Dividing the volatile compounds into two groups – consisting of (1) hexanal, (E)‐2‐hexenal, octanal, nonanal, and decanal, and (2) sulcatone, humulene, and benzyl alcohol – obliterated effectiveness, revealing synergism between compounds. Although volatiles did not stimulate oviposition, they significantly contributed to the distribution of eggs by increasing the landing rates on treated artificial leaves.  相似文献   
4.
According to World Health Organization obesity is one of the greatest public health challenges of the 21st century. It has tripled since the 1980s and the numbers of those affected continue to rise at an alarming rate, especially among children. There are number of devices that act as a prevention measure to boost person?s motivation for physical activity and its levels. The placement of these devices is not restricted thus the measurement errors that appear because of the body rheology, clothes, etc. cannot be eliminated. The main objective of this work is to introduce a tool that can be applied directly to process measured accelerations so human body surface tissue induced errors can be reduced. Both the modeling and experimental techniques are proposed to identify body tissue rheological properties and prelate them to body mass index. Multi-level computational model composed from measurement device model and human body surface tissue rheological model is developed. Human body surface tissue induced inaccuracies can increase the magnitude of measured accelerations up to 34% when accelerations of the magnitude of up to 27 m/s2 are measured. Although the timeframe of those disruptions are short – up to 0.2 s – they still result in increased overall measurement error.  相似文献   
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Gas chromatography and mass spectrometry analyses of crude sex pheromone gland extracts revealed that virgin Synanthedon tipuliformis (Clerck), currant borer (Lepidoptera: Sesiidae) females, produced 6 compounds, structurally related to sex pheromone components of clearwing moths. By comparison of retention times and mass spectra of natural products with corresponding properties of synthetic standards, these compounds were identified as: (2E,13Z)-octadeca-2,13-dien-1-yl acetate (E2,Z13-18:OAc), (3E,13Z)-octadeca-3,13-dien-1-yl acetate (E3,Z13-18:OAc), (13Z)-octadec-13-en-1-yl acetate (Z13-18:OAc), (2E,13Z)-octadeca-2,13-dien-1-ol (E2,Z13-18:OH), (13Z)-octadec-13-en-1-ol (Z13-18:OH) and octadecan-1-ol (18:OH) in the ratio 100:0.7:2.7:3.2:traces:traces. The first 3 compounds were previously known to occur in the sex pheromone gland extracts of currant borers, while the last 3 chemicals are now reported for the first time. Trapping tests carried out in the black currant field revealed that E2,Z13-18:OAc, when tested separately, attracted S. tipuliformis males, while addition of E3,Z13-18:OAc to the main component increased the effectiveness of E2,Z13-18:OAc over seven times. The attractiveness of 6 component lures did not differ significantly from the one of the binary mixture, confirming that E2,Z13-18:OAc and E3,Z13-18:OAc in the ratio100:0.7 are essential sex pheromone components of S. tipuliformis. Trapping tests carried out at the dwelling place of Synanthedon scoliaeformis (Borkhausen) (Lepidoptera: Sesiidae) revealed that, in addition to intraspecific synergistic effect, E3,Z13-18:OAc increased the specificity of the pheromone signal of S. tipuliformis, acting by intraspecific mode as an attraction antagonist against S. scoliaeformis males. By this way, it ensured the specificity of the sex attraction signal of the currant borer. Consequently, both compounds E2,Z13-18:OAc and E3,Z13-18:OAc have to be present in pheromone formulations used for monitoring and/or control of S. tipuliformis to avoid effecting non-target species. Other compounds identified from the sex pheromone gland of S. tipuliformis did not show any significant interspecific activity for males of S. scoliaeformis, however, they provide a basis to achieve specificity of a pheromone signal of S. tipuliformis and could act as attraction antagonists against other clearwing moth species which, like S. tipuliformis, employ E2,Z13-18:OAc as their sex pheromone component.  相似文献   
7.
Urine samples from 14 mares, belonging to five breeds, were collected at estrus and diestrus to search for estrous specific volatile compounds which could be used to determine ovulation time. Around 150 volatiles were collected from urine head-space samples by solid phase micro extraction technique, and analyses were conducted by gas chromatography-mass spectrometry methods. Comparison of chromatographic profiles of volatile substances revealed that concentrations of m- and p-cresols were significantly greater during estrus while diethylphthalate was more abundant at diestrus. Monitoring of m- and p-cresols during the period of estrus and a few days before and after estrus revealed irregular changes in amounts of cresols until 3-4 days before ovulation when the concentration of the compounds began to increase with peaks 1 day before ovulation. On the day when ovulation occurred, amounts of the metabolites decreased sharply, almost to basal concentrations, and remained at these concentrations for 6 days - when sampling was finished. In four of the mares changes in the concentration of diethylphthalate were less pronounced and more temporally variable compared with those of cresols. Based on reproducible temporal changes in concentrations of m- and p-cresols, with respect to the time of ovulation, a noninvasive test to determine a precise insemination time could occur. This would save time, reduce costs and simplify the procedure.  相似文献   
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Herbivorous insects use highly specific volatiles or blends of volatiles characteristic to particular plant species to locate their host plants. Thus, data on olfactory preferences can be valuable in developing integrated pest management tools that deal with manipulation of pest insect behaviour. We examined host plant odour preferences of the tomato leafminer, Liriomyza bryoniae (Kaltenbach) (Diptera: Agromyzidae), which is an economically important agricultural pest widespread throughout Europe. The odour preferences of leafminers were tested in dependence of feeding experiences. We ranked host plant odours by their appeal to L. bryoniae based on two‐choice tests using a Y‐tube olfactometer with five host plants: tomato, Solanum lycopersicum Mill.; bittersweet, Solanum dulcamara L.; downy ground‐cherry, Physalis pubescens L. (all Solanaceae); white goosefoot, Chenopodium album L. (Chenopodiaceae); and dead nettle, Lamium album L. (Lamiaceae). The results imply that ranking of host plant odours by their attractiveness to L. bryoniae is complicated due to the influence of larval and adult feeding experiences. Without any feeding experience as an adult, L. bryoniae males showed a preference for the airflow with host plant odour vs. pure air, whereas females did not display a preference. Further tests revealed that adult feeding experience can alter the odour choice of L. bryoniae females. After feeding experience, females showed a preference for host plant odour vs. pure air. Feeding experience in the larval stage influenced the choice by adults of both sexes: for males as well as females reared on bittersweet the odour of that plant was the most attractive. Thus, host feeding experience both in larval and/or adult stage of polyphagous tomato leafminer L. bryoniae influences host plant odour preference by adults.  相似文献   
10.
BackgroundEarly diagnosis of bacteremia and sepsis in pediatric oncology patients with febrile neutropenia still remains unresolved task due to lack of sensitive and specific laboratory markers particularly at the beginning of the infectious process. The objective of our study was to assess the potentiality of interleukin-10 (IL-10) to predict or exclude bacteremia or sepsis at the beginning of febrile episode in childhood oncology patients.MethodsA total of 36 febrile neutropenic episodes in 24 children were studied. Serum samples were collected after confirmation of febrile neutropenia and analyzed using automated random access analyzer.ResultsThe sensitivity of IL-10 was 73% and specificity – 92% (cut-off = 18 pg/ml, area under the curve – 0.87, 95% CI for sensitivity 39–94%, 95% CI for specificity 74–99%) with negative predictive value (NPV) – 83%.ConclusionsIL-10 evaluation might be used as an additional diagnostic tool for clinicians in excluding bacteremia or clinical sepsis in oncology patients with febrile neutropenia because of high NPV and specificity.  相似文献   
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