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631.
J. Zeil 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1996,180(1):25-37
Hymenopteran insects perform systematic learning flights on departure from their nest, during which they acquire a visual
representation of the nest environment. They back away from and pivot around the nest in a series of arcs while turning to
view it in their fronto-lateral visual field. During the initial stages of the flights, turning rate and arc velocity relative
to the nest are roughly constant at 100–200° s−1 and are independent of distance, since the insects increase their flight speed as they back away from the pivoting centre.
In this paper I analyse how solitary wasps control their flight by having them perform learning flights inside a rotating
striped drum.
The wasps' turning velocity is under visual control. When the insects fly inside a drum that rotates around the nest as a
centre, their average turning rate is faster than normal when they fly an arc into the direction of drum rotation and slower
when they fly in the opposite direction. The average slip speed they experience lies within 100–200° s−1. The wasps also adjust their flight speed depending on the rotation of the drum. They modulate their distance from the pivoting
centre accordingly and presumably also their height above ground, so that maximal ground slip is on average 200°␣s−1. The insects move along arcs by short pulses of translation, followed by rapid body turns to correct for the change in retinal
position of the nest entrance. Saccadic body turns follow pulses of translation with a delay of 80–120 ms. The optomotor response
is active during these turns.
The control of pivoting flight most likely involves three position servos, to control the retinal position of both the azimuth
and the altitude of nest and the direction of flight relative to it, and two velocity servos, one constituting the optomotor
reflex and the other one serving to clamp ground slip at about 200° s−1. The control of ground slip is the prime source of the dynamic constancy of learning flights, which may help wasps to scale
the pivoting parallax field they produce during these flights. Constant pivoting rate may in addition be important for the
acquisition of a regular sequence of snapshots and in scanning for compass cues.
Accepted : 31 July 1996 相似文献
632.
In high-throughput biotechnology and structural biology, molecular cloning is an essential prerequisite for attaining high yields of recombinant protein. However, a rapid, cost-effective, easy clone screening protocol is still required to identify colonies with desired insert along with a cross check method to certify the expression of the desired protein as the end product. We report an easy, fast, sensitive and cheap visual clone screening and protein expression cross check protocol employing gold nanoparticle based plasmonic detection phenomenon. This is a non-gel, non-PCR based visual detection technique, which can be used as simultaneous high throughput clone screening followed by the determination of expression of desired protein. 相似文献
633.
Adult horseshoe crabs Limulus polyphemus have long served as models for the study of vision in marine arthropods. Yet,little is known about the ability of early life history stages to detect and respond to visual cues.We examined the visually directed movements of larvae and first stage juveniles to horizons containing dark visual targets of different sizes.The study tested the hypotheses that (1) larval and juvenile crabs can detect and respond to visual targets and (2) the direction of orientation varies ... 相似文献
634.
Marco Martiniello 《Ethnic and racial studies》2017,40(8):1184-1190
The aim of the article is to discuss the advantages of using visual sociology approaches and methods in migration, ethnic and racial studies. It first briefly presents the history of visual sociology and what it consists of. It then moves to immigration, ethnic and racial studies by presenting some examples of visual approaches in a few selected research projects dealing with immigrant electoral politics, the history of migration and music and ethnic politics. 相似文献
635.
Kazuo Fujita 《Primates; journal of primatology》1993,34(2):133-140
Three adult pigtail monkeys pressed a lever to see pictures of pigtail and Japanese monkeys with a variety of physical features
being removed. The features included head, tail, body, background, and color. The duration and the interval of exposure of
these visual stimuli were dependent upon subjects' responding. Preferences for those pictures were evaluated by the ratio
of lever-pressing duration to interval of lever-pressing. Two of the subjects showed a consistent preference to see pictures
of pigtail monkeys over those of Japanese monkeys. Though this preference tended to maintain when these physical features
were removed, it became relatively weak when head and head + tail were removed. These results suggest that pigtail macaques
may discriminate species based not on a single characteristics but on some combination of features, and that head may be relatively
important than the other features. 相似文献
636.
Laura Perini 《Biology & philosophy》2005,20(2-3):257-269
Molecular biologists and biochemists often use diagrams to present hypotheses. Analysis of diagrams shows that their content can be expressed with linguistic representations. Why do biologists use visual representations instead? One reason is simple comprehensibility: some diagrams present information which is readily understood from the diagram format, but which would not be comprehensible if the same information was expressed linguistically. But often diagrams are used even when concise, comprehensible linguistic alternatives are available. I explain this phenomenon by showing why diagrammatic representation is especially well suited for a particular kind of explanation common in molecular biology and biochemistry: namely, functional analysis, in which a capacity of the system is explained in terms of capacities of its component parts. 相似文献
637.
F. L. Wäckers W. J. Lewis 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1999,184(4):387-393
Visual learning by the larval parasitoid, Microplitis croceipes Cresson (Hymenoptera: Braconidae) was investigated in flight chamber studies. During conditioning, free-ranging parasitoids
were given a choice between two visual alternatives, only one of which offered a host larva. By using alternatives that differed
in either color, shape or pattern, parasitoids could be conditioned to distinguish host sites on the basis of each of these
visual cues. Tests during which no reward was offered were conducted following six rewards (ovipositions) at one of the two
alternative stimuli. The test results reveal that M. croceipes learned to distinguish between shapes more readily than between colors or patterns. This high rate of shape learning in this
parasitoid is in strong contrast to the learning capacity of honey bees, which have been shown to learn color better than
pattern and pattern better than shapes. It is argued that the difference in learning capacities between M. croceipes and the honey bee may reflect the different selection pressures imposed on these two species by their natural ecological
needs. The high rate of shape learning in M. croceipes may be adaptive in dealing with the homochromatic but multishaped environment in which parasitoids have to locate their herbivorous
hosts.
Accepted: 30 January 1999 相似文献
638.
Peter Ekström 《Cell and tissue research》1982,225(3):507-524
The retinofugal projections in the eel were studied by use of the cobalt-filling technique. The optic tract projects contralaterally to the hypothalamic optic nucleus, the anterior periventricular nucleus, the lateral geniculate nucleus, the dorsomedial optic nucleus, four pretectal recipient areas, the optic tectum, and the tegmentum. Small ipsilateral projections were demonstrated in the hypothalamic optic nucleus, the dorsomedial optic nucleus, and the optic tectum. 相似文献
639.
《Cell reports》2020,30(10):3261-3269.e4
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640.
《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2013,44(2):217-224
In silicio design plays a fundamental role in the endeavour to synthesise biological systems. In particular, computer-aided design software enables users to manage the complexity of biological entities that is connected to their construction and reconfiguration. The software’s graphical user interface bridges the gap between the machine-readable data on the algorithmic subface of the computer and its human-amenable surface represented by standardised diagrammatic elements. Notations like the Systems Biology Graphical Notation (SBGN), together with interactive operations such as drag & drop, allow the user to visually design and simulate synthetic systems as ‘bio-algorithmic signs’. Finally, the digital programming process should be extended to the wet lab to manufacture the designed synthetic biological systems. By exploring the different ‘faces’ of synthetic biology, I argue that in particular computer-aided design (CAD) is pushing the idea to automatically produce de novo objects. Multifaceted software processes serve mutually aesthetic, epistemic and performative purposes by simultaneously black-boxing and bridging different data sources, experimental operations and community-wide standards. So far, synthetic biology is mainly a product of digital media technologies that structurally mimic the epistemological challenge to take both qualitative as well as quantitative aspects of biological systems into account in order to understand and produce new and functional entities. 相似文献