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71.
The success of a species depends on its ability to assess its environment and to decide accordingly which behaviors are most appropriate. Many animal species, from bacteria to mammals, are able to communicate using interspecies chemicals called pheromones. In addition to exerting physiological effects on individuals, for social species, pheromones communicate group social structure. Communication of social structure is important to social insects for the allocation of its working members into coordinated suites of behaviors. We tested effects of long-term treatment with brood pheromone on suites of honey bee brood rearing and foraging behaviors. Pheromone-treated colonies reared significantly greater brood areas and more adults than controls, while amounts of stored pollen and honey remained statistically similar. Brood pheromone increased the number of pollen foragers and the pollen load weights they returned. It appeared that the pheromone-induced increase in pollen intake was directly canalized into more brood rearing. A two-way pheromone priming effect was observed, such that some workers from the same age cohorts showed an increased and extended capacity to rear larvae, while others were recruited at significantly younger ages into pollen-specific foraging. Brood pheromone affected suites of nursing and foraging behaviors allocating worker and pollen resources associated with an important fitness trait, colony growth.  相似文献   
72.
Theory predicts that females in species with matrilineal dominance hierarchies should use nepotistic support systems to maintain their family’s rank. Female Old World monkeys, however, form alliances against other females at surprisingly low rates. Nonetheless, in many species, females utter threat vocalizations when observing others’ disputes, suggesting that these vocalizations may function as ‘vocal alliances’. We describe a playback experiment testing the efficacy of vocal alliances in free-ranging female baboons. Subjects were played the same female’s threat-grunts under three separate conditions: after being threatened by the signaller’s close relative to mimic kin support, after being threatened by a female maternally unrelated to the signaller to mimic non-kin support, and after a friendly interaction with the signaller’s close relative as a control. Subjects responded more strongly to the playback and avoided the signaller and her matrilineal relatives for a longer period of time in kin support trials than in either non-kin support or no aggression trials. In contrast, there was no difference in subjects’ behaviour between non-kin support and no aggression trials. These results corroborate observational data showing that vocal support occurs at a higher rate than physical support in female baboons, and that kin are more likely to provide vocal support than non-kin. We conclude that vocal support plays a similar role as physical support in the alliances of female baboons.  相似文献   
73.
The number of fatal occupational injuries (FOI), the number of scientific publications in ergonomics (SP) and the gross domestic product (GDP) of 30 countries were investigated for their mutual dependence. This article shows that, although the ratio of FOI/SP decreases exponentially with a linear increase in the GDP, GDP may be only one of the major influencing factors.  相似文献   
74.
Environment, Development and Sustainability - Our aim is to determine the factors influencing a visitor’s decision to stay in a green accommodation facility. Visitors from six tourist sites...  相似文献   
75.
76.
Time-related accident risk in shift work may be attributed to internal factors, such as fatigue, level of performance, sleep propensity, and to some external factors, like shift system, physical and social environment. Six hundred and sixty-eight events in the metallurgical industry have been analysed in terms of time of day, time on task, consecutive day of the shift block, day of the week, and season.

The injury rate was similar on all shifts but more severe accidents happened in the nighttime. Somewhat more injuries occurred in the second half of the shift, in the second part of a shift block, and in summer compared with winter. There were fewer injuries at weekends.  相似文献   
77.
78.
Journal of Material Cycles and Waste Management - In recent years, the use of residue for the production of new composite materials has gained prominence as it enables reuse of materials and...  相似文献   
79.
The toxicities of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), 2,4-dinitrotoluene (2,4-DNT), and 2,6-dinitrotoluene (2,6-DNT) to terrestrial plants alfalfa (Medicago sativa L.), Japanese millet (Echinochloa crusgalli L.), and perennial ryegrass (Lolium perenne L.) were determined in Sassafras sandy loam soil using seedling emergence, fresh shoot, and dry mass measurement endpoints. A 13-week weathering and aging of energetic materials in soils, which included wetting and drying cycles, and exposure to sunlight of individual soil treatments, was incorporated into the study design to better reflect the soil exposure conditions in the field than toxicity determinations in freshly amended soils. Definitive toxicity tests showed that dinitrotoluenes were more phytotoxic for all plant species in freshly amended treatments based on EC20 values for dry shoot ranging from 3 to 24mgkg(-1) compared with values for TNB or TNT ranging from 43 to 62mgkg(-1). Weathering and aging of energetic materials (EMs) in soil significantly decreased the toxicity of TNT, TNB or 2,6-DNT to Japanese millet or ryegrass based on seedling emergence, but significantly increased the toxicity of all four EMs to all three plant species based on shoot growth. Exposure of the three plant species to relatively low concentrations of the four compounds initially stimulated plant growth before the onset of inhibition at greater concentrations (hormesis).  相似文献   
80.
Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org/10.1007/s11356-021-12759-3  相似文献   
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