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1.
Tobias Gerlach Dennis Sprenger Nico K. Michiels 《Proceedings. Biological sciences / The Royal Society》2014,281(1787)
Fluorescence enables the display of wavelengths that are absent in the natural environment, offering the potential to generate conspicuous colour contrasts. The marine fairy wrasse Cirrhilabrus solorensis displays prominent fluorescence in the deep red range (650–700 nm). This is remarkable because marine fishes are generally assumed to have poor sensitivity in this part of the visual spectrum. Here, we investigated whether C. solorensis males can perceive the fluorescence featured in this species by testing whether the presence or absence of red fluorescence affects male–male interactions under exclusive blue illumination. Given that males respond aggressively towards mirror-image stimuli, we quantified agonistic behaviour against mirrors covered with filters that did or did not absorb long (i.e. red) wavelengths. Males showed significantly fewer agonistic responses when their fluorescent signal was masked, independent of brightness differences. Our results unequivocally show that C. solorensis can see its deep red fluorescent coloration and that this pattern affects male–male interactions. This is the first study to demonstrate that deep red fluorescent body coloration can be perceived and has behavioural significance in a reef fish. 相似文献
2.
Markus Hoffmann Nadine Krüger Pawel Zmora Florian Wrensch Georg Herrler Stefan P?hlmann 《PloS one》2016,11(3)
New World bats have recently been discovered to harbor influenza A virus (FLUAV)-related viruses, termed bat-associated influenza A-like viruses (batFLUAV). The internal proteins of batFLUAV are functional in mammalian cells. In contrast, no biological functionality could be demonstrated for the surface proteins, hemagglutinin (HA)-like (HAL) and neuraminidase (NA)-like (NAL), and these proteins need to be replaced by their human counterparts to allow spread of batFLUAV in human cells. Here, we employed rhabdoviral vectors to study the role of HAL and NAL in viral entry. Vectors pseudotyped with batFLUAV-HAL and -NAL were able to enter bat cells but not cells from other mammalian species. Host cell entry was mediated by HAL and was dependent on prior proteolytic activation of HAL and endosomal low pH. In contrast, sialic acids were dispensable for HAL-driven entry. Finally, the type II transmembrane serine protease TMPRSS2 was able to activate HAL for cell entry indicating that batFLUAV can utilize human proteases for HAL activation. Collectively, these results identify viral and cellular factors governing host cell entry driven by batFLUAV surface proteins. They suggest that the absence of a functional receptor precludes entry of batFLUAV into human cells while other prerequisites for entry, HAL activation and protonation, are met in target cells of human origin. 相似文献
3.
Peter Van Bogaert Lieve Peremans Nadine Diltour Danny Van heusden Tinne Dilles Bart Van Rompaey Donna Sullivan Havens 《PloS one》2016,11(4)
The aim of the study reported in this article was to investigate staff nurses’ perceptions and experiences about structural empowerment and perceptions regarding the extent to which structural empowerment supports safe quality patient care. To address the complex needs of patients, staff nurse involvement in clinical and organizational decision-making processes within interdisciplinary care settings is crucial. A qualitative study was conducted using individual semi-structured interviews of 11 staff nurses assigned to medical or surgical units in a 600-bed university hospital in Belgium. During the study period, the hospital was going through an organizational transformation process to move from a classic hierarchical and departmental organizational structure to one that was flat and interdisciplinary. Staff nurses reported experiencing structural empowerment and they were willing to be involved in decision-making processes primarily about patient care within the context of their practice unit. However, participants were not always fully aware of the challenges and the effect of empowerment on their daily practice, the quality of care and patient safety. Ongoing hospital change initiatives supported staff nurses’ involvement in decision-making processes for certain matters but for some decisions, a classic hierarchical and departmental process still remained. Nurses perceived relatively high work demands and at times viewed empowerment as presenting additional. Staff nurses recognized the opportunities structural empowerment provided within their daily practice. Nurse managers and unit climate were seen as crucial for success while lack of time and perceived work demands were viewed as barriers to empowerment. 相似文献
4.
Scaling of metabolic rate with body mass and temperature in teleost fish 总被引:27,自引:0,他引:27
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Summary An electrical fusion method has been used to form somatic hybrids between protoplasts of two mutant cell lines of sycamore tissue culture cells. Both mutants will not grow in a hypoxanthine-aminopterin-thymidine (HAT) medium. It was possible to select the fused hybrids from homospecific fusion products and nonfused protoplasts by the use of HAT medium. In this way the viability and regeneration of the fused cells during the first few weeks of culture could be evaluated. An electron microscopic examination of the fusion process showed that it occurred at a series of points along the surface of the plasmalemma. Cytoplasmic bridges between the two cells were formed separated by vesicles which later dispersed to give complete cytoplasmic continuity between the cells. 相似文献
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E S Dennis M M Sachs W L Gerlach E J Finnegan W J Peacock 《Nucleic acids research》1985,13(3):727-743
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H. Christopher Wilson Nadine C. Milos 《In vitro cellular & developmental biology. Plant》1987,23(5):323-331
Summary This study investigates the nutritional requirements ofXenopus laevis neural crest cells and melanophores developing in vitro. A comparison is made between the growth and differentiation of cells
in serum-containing medium and a chemically defined, serum-free medium that we have designed. Our chemically defined medium
is more efficient than serum-supplemented medium in promoting proliferation of these cells. Several supplements are required
to enhance culture development. These include insulin, α-melanocyte stimulating hormone, somatotropin, luteotrophic hormone,
linoleic acid, uridine, and putrescine. In addition, collagen and fibronectin provide the most conductive environment tested
for cell migration and adhesion.
This work was supported by establishment and major equipment grants from the Alberta Heritage Foundation for Medical Research
to N. C. M. Nadine C. Milos is a Heritage Medical Research Scholar of the Alberta Heritage Foundation for Medical Research. 相似文献
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