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131.
Abraham KM Radhakrishnan T 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(2):151-155
Paratelphusa hydrodromus (Herbst.) was exposed to 50 ppm nickel chloride solution for a period of 10 days under laboratory conditions. The gills of the treated and non-treated animals were sectioned, stained and examined under a compound microscope and noticed significant changes such as enlargement of gill lamellae, lifting up and rupture of epithelial cells, enlargement of mid rachis, hyperplasia and hypertrophy, appearance of pyknotic nuclei and a general necrosis in the treated gills. Results suggest that a comparatively low concentration of nickel (50 ppm) is enough to elicit pathological changes in Paratelphusa hydrodromus. 相似文献
132.
Kin selection and inclusive fitness theories predict that, in hopeless queenless (QL) groups, competition or cooperation will occur over male production among workers of different patrilines. Competition is expected to involve mutual inhibition of reproduction and to affect fertility advertisement. To examine kin effect on these phenomena, we studied QL groups of honeybee workers comprising three types of kin structure: groups composed of pure single patrilines, groups composed of three mixed patrilines (all originating from colonies headed by single-drone-inseminated queens), and control groups composed of bees originating from naturally mated queens. Global assessment of ovarian development, irrespective of patriline composition, revealed no differences among group types. In contrast, the performance of specific patrilines revealed that, in the three-mixed-patriline groups, some patrilines were reproductively suppressed compared to their performance when reared as a pure single patriline, resulting in an uneven share of reproduction. Analysis of the fertility signal produced by Dufour's gland revealed kin composition effects, which may reflect the bees' competitive efforts. Although patriline effects on worker reproductive superiority have been shown in QL colonies, we were able to investigate specific patriline performance both in competitive and noncompetitive situations here for the first time. The results are consistent with the hypothesis that reproductive and pheromonal competitions in QL groups are affected by the number of subfamilies populating a colony and that these act as coalitions. The results also emphasize that within-colony heterogeneity, in the form of multiple patrilines, has far-reaching consequences on social evolution. 相似文献
133.
Caste-specific pheromone biosynthesis is a prerequisite for reproductive skew in the honeybee. Nonetheless, this process is
not hardwired but plastic, in that egg-laying workers produce a queen-like pheromone. Studies with Dufour’s gland pheromone
revealed that, in vivo, workers’ gland biosynthesis matches the social status of the worker, i.e., sterile workers showed
a worker-like pattern whereas fertile workers showed a queen-like pattern (production of the queen-specific esters). However,
when incubated in vitro, the gland spontaneously exhibits the queen-like pattern, irrespective of its original worker type,
prompting the notion that ester production in workers is under inhibitory control that is queen-dependent. We tested this
hypothesis by exposing queen or worker Dufour’s glands in vitro to brain extracts of queens, queenright (sterile) workers
and males. Unexpectedly, worker brain extracts activated the queen-like esters biosynthesis in workers’ Dufour’s gland. This
stimulation was gender-specific; queen or worker brains demonstrated a stimulatory activity, but male brains did not. Queen
gland could not be further stimulated. Bioassays with heated and filtered extracts indicate that the stimulatory brain factor
is below 3,000 Da. We suggest that pheromone production in Dufour’s gland is under dual, negative–positive control. Under
queenright conditions, the inhibitor is released and blocks ester biosynthesis, whereas under queenless conditions, the activator
is released, activating ester biosynthesis in the gland. This is consistent with the hypothesis that queenright workers are
unequivocally recognized as non-fertile, whereas queenless workers try to become “false queens” as part of the reproductive
competition. 相似文献
134.
Akinsola Gbenga Daniel Awosusi Abraham Ayobamiji Kirikkaleli Dervis Umarbeyli Sukru Adeshola Ibrahim Adebayo Tomiwa Sunday 《Environmental science and pollution research international》2022,29(7):10077-10090
Environmental Science and Pollution Research - The present study assesses the effect of public-private partnerships in energy and financial development on Brazil’s ecological footprint and... 相似文献
135.
Akadiri Seyi Saint Adebayo Tomiwa Sunday Riti Joshua Sunday Awosusi Abraham Ayobamiji Inusa Eshiozemhe Micheal 《Environmental science and pollution research international》2022,29(59):89045-89062
Environmental Science and Pollution Research - Currently, the most crucial economic and ecological issues are related to environmental degradation and sustainability. On this backdrop, this paper... 相似文献
136.
Deka Abraham Cavusoglu Behiye Dube Sindiso 《Environmental science and pollution research international》2022,29(10):14185-14194
Environmental Science and Pollution Research - The current study is aimed at investigating the relationship between the use of renewable energy, the rate of currency exchange, and the rate of... 相似文献