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971.
The growing enthusiasm for STEAM (STEM + Arts) initiatives reflects the rich potential for inquiry and integration between arts and sciences. Biologically informed poetry is an active interdisciplinary area of creation and analysis that requires biologically attuned illustration and translation to retain its STEAM effectiveness across linguistic barriers. Pablo Neruda, Chilean poet and Nobel laureate, was a keen observer and informed scholar who wove his scientific knowledge into his poetry. He was particularly obsessed with the sea and featured marine invertebrates in many of his works. The molluscs in his poem “Mollusca Gongorina” are unusual in being specified by their Latin genera. In this zoopoetic analysis, we first ask whether the 11 specimens can be identified to species and find that eight have ready identifications based on morphology in the poem's text, and three have likely identifications based on the poem's themes. We then examine illustrations and translations of the poem, identify where they are consonant or dissonant with the biology of the original, and propose alternative translations informed by the species' identities. Our zoopoetic approach to what could today be considered a STEAMy poem surfaces the beauty of its imagery and narrative, reflects the biological sophistication of the poet, enhances the coherence of its translations making it accessible to a wider audience, and allows it to enhance the biological literacy of the reader.  相似文献   
972.
The water balance relationships of adult females and pupae of two populations (Australian and Taiwan) of the parasitic wasp Ageniaspis citricola, a biological control agent of the citrus leafminer Phyllocnistis citrella, were compared to determine whether habitat preferences might differ between them. No differences were detected between Australian and Taiwan strains of the wasp during the pupal stage, but adult females from the Australian strain had lower net water loss rates than the parasitoid adults from Taiwan. This implies a greater moisture requirement by adults of the Taiwan strain, which should be considered before they are released into a new environment in classical biological control programs.  相似文献   
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A human/mouse hybridoma was developed which has the property of secreting a human bone resorbing factor similar or identical to the osteoclast activating factor (OAF) isolated from human tonsil lymphocytes. Mouse plasmacytoma cells negative for OAF production were fused with an enriched subpopulation of human tonsil lymphocytes that had been activated with phytohemagglutinin (PHA) to produce OAF (G. E. Nedwin, M. A. Mohler, and R. A. Luben, submitted for publication). Culture supernatants from mixed hybridomas contained a bone resorbing protein shown to cause the release of 45Ca from previously labeled mouse calvaria. The bone resorbing activity from these hybridomas was inhibited by the presence of OAF-specific monoclonal antibodies. Several hybridomas retained OAF production following limited dilution cloning. One clone, CD6.20, showed a biphasic dose-response curve for bone resorption similar to that of purified OAF from PHA-activated human tonsil lymphocytes. OAF production in the CD6.20 cell line has been retained for over 100 passages. Karyotype analysis of this cell shows the presence of human chromosomes 10 and 18 and the X chromosome.  相似文献   
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Recognition of an Escherichia Operator by a Salmonella Repressor   总被引:4,自引:2,他引:2       下载免费PDF全文
Escherichia coli leu+ episomes were transferred to Salmonella typhimurium. The levels of two leucine-forming enzymes were normal (low) in the resulting merodiploids, suggesting that the putative Samonella leucine repressor recognizes the Escherichia leucine operator.  相似文献   
978.
Comparisons between transgenic (T) and wild-type Metaseiulus occidentalis colonies (COS) were made under laboratory conditions as part of a risk assessment effort prior to proposed field releases. There were no differences between the transgenic T18 colony and the COS strain in the daily egg production, hatchability at three temperatures and four relative humidity (RH) conditions, diapause incidence, or proportion of female progeny produced. Metaseiulus occidentalis eggs do not hatch at 38°C under any RH tested, nor at 33.5°C under 100% RH, indicating that high temperature and extreme RH affect egg hatch negatively. At 28.5 and 33.5°C, fewer eggs hatched at 32.5% than at 75.5 and 93% RH. Metaseiulus occidentalis cannot survive on any plant tested without prey nor on a diet of pollen alone; adult female mites cannot prey or survive on a diet of eggs and larvae of two lepidopteran species, indicating that the suitability of food sources has not been altered in the transgenic strain. Two subcolonies, derived from two transgenic strains using single females, differed in the rate of egg hatch at 28.5°C under 32.5 and 100% RH, indicating that reduced genetic variation and/or random genetic drift in the two lines may have led to differences in some biological characters. Since we did not find any significant differences between the T18 and COS colonies in the traits tested, the T18 colony is not expected to exhibit any new biological attributes in a proposed short-term field release.  相似文献   
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