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D. W. Keats 《Journal of fish biology》1991,38(1):67-72
Green sea urchins were the most abundant food species (62% by weight) in American plaice (all female) collected from an area in eastern Newfoundland where sandy bottom abuts urchin dominated bedrock. Of secondary importance were capelin (12.9% by weight), which were spawning in the area when the samples were obtained. The results suggest that American plaice may be important predators of urchins in such habitats. 相似文献
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W. Siriwong K. Thirakhupt D. Sitticharoenchai J. Rohitrattana P. Thongkongowm M. Borjan 《人类与生态风险评估》2008,14(5):1086-1097
Food consumption is one of the main routes of human exposure to organochlorine pesticide residues (OCPRs). To assess the potential health risks associated with OCPRs contaminants due to freshwater organism consumption, a number of vegetables, prawn, snail, and fish were collected from Khlong 7 (canal), Rangsit agricultural area, Pathum-Thani Province, Thailand. The samples were extracted using a multiresidue extraction method and then analyzed by gas chromatography with microelectron capture detector (μ -ECD). The results show that low concentrations of OCPRs were detected in parts per billion (ppb) levels. Based on a plausible worst-case scenario, the local population could be at risk for cancer due to consumption of fish contaminated by α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, dieldrin, DDD, DDE, and DDT. Likewise, individuals may be at risk from consumption of Lanchester's freshwater prawn Macrobrachium lanchesteri, freshwater snail Filopaludina mertensi, swamp morning-glory Ipomomea aquatica, neptunia Neptunia oleracea, and water lily Nymphaea lotus because these species all contained elevated concentrations of α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, and dieldrin. 相似文献
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Physiological state influences the antennal response of Anastrepha obliqua to male and host volatiles 下载免费PDF全文
Humberto Reyes Edi A. Malo Jorge Toledo Samuel Cruz‐Esteban Julio C. Rojas 《Physiological Entomology》2017,42(1):17-25
The sexual and host‐related behaviours of the fruit fly Anastrepha obliqua Macquart (Diptera: Tephritidae) are mediated by volatile compounds. However, whether the physiological state of this species affects its antennal and behavioural responses to semiochemicals is unknown. The effects of age, mating status, diet and the topical application of methoprene, a Juvenile hormone analogue (JHA), on the antennal sensitivity of this tephritid fruit fly species to selected male [(Z)‐3‐nonenol] and host fruit volatiles (ethyl benzoate, ethyl hexanoate, ethyl butyrate and trans‐β‐ocimene) are investigated using electroantennography (EAG). Overall, (Z)‐3‐nonenol and ethyl benzoate elicit the highest EAG responses in both sexes. Flies of both sexes aged 1, 5 and 10 days old show higher EAG responses to the tested compounds compared with flies aged 20 days old. Virgin females and males show higher EAG responses to volatile compounds than mated flies. Females and males fed with sugar plus protein show higher antennal responses to volatiles compared with flies fed sugar or protein alone. Flies of both sexes treated with methoprene show higher antennal responses than flies treated with acetone (control). These results suggest that the peripheral olfactory system in A. obliqua is modulated by the physiological state of the flies. 相似文献
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Allison C. Veronda Kelly C. Allison Ross D. Crosby Leah A. Irish 《Chronobiology international》2020,37(3):375-394
ABSTRACTChrononutrition, or the circadian timing of food intake, has garnered attention as a topic of study due to its associations with health (e.g. weight gain); however, a valid and reliable assessment of chrononutrition in daily life has not yet been developed. This paper details the development and initial reliability and validity testing of the Chrononutrition Profile – Questionnaire (CP-Q). The CP-Q assesses six components of chrononutrition that are likely to influence health (breakfast skipping, largest meal, evening eating, evening latency, night eating, and eating window). This questionnaire is designed to assess general chrononutrition behaviors and preferred timing of food intake. The CP-Q can be used as a sole evaluation of chrononutrition, and can also be utilized in conjunction with existing dietary measures to provide a comprehensive assessment of one’s eating behaviors. This measure offers health-care professionals, researchers, and stakeholders a cost-effective and comprehensive method of evaluating chrononutrition and identifying targets for health improvement. 相似文献