The Orientation of Ants

1954 ◽  
Vol 31 (3) ◽  
pp. 341-355
Author(s):  
D. M. VOWLES
Keyword(s):  
Honey Bee ◽  
Polarized Light ◽  
Stimulus Light ◽  
Experimental Conditions ◽  
Directional Stimulus ◽  
Actual Relationship

1. Von Frisch has shown that in the honey-bee orientation established in relation to one directional stimulus (light) can be transferred to another directional stimulus (gravity or polarized light). In the present work the orientation of ants has been studied in experiments in which one type of directional stimulus has been replaced by another. Light, gravity and polarized light have been used as stimuli. 2. When light and gravity are interchanged, the ant's successive orientations to the two stimuli are correlated. The angle between the track and the stimulus is the same for both orientations. 3. When light and polarized light are interchanged, the ant's successive orientations are again correlated. The actual relationship depends on the experimental conditions. 4. When polarized light and gravity are interchanged there is no significant correlation between successive orientations. 5. It is suggested that in bees and ants there is a single taxis mechanism for orientation to light, polarized light and gravity, and that the ‘setting’ of this mechanism during an orientation to one stimulus persists and partially determines the subsequent orientation to another stimulus.

scholarly journals Optimization ofs-Polarization Sensitivity in Apertureless Near-Field Optical Microscopy

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Yuika Saito ◽  
Yoshiro Ohashi ◽  
Prabhat Verma
Keyword(s):  
Spatial Resolution ◽  
Rayleigh Scattering ◽  
Incident Light ◽  
Near Field ◽  
Polarized Light ◽  
Polarization Sensitivity ◽  
Experimental Setup ◽  
Experimental Conditions ◽  
General Belief ◽  
Polarization Configuration

It is a general belief in apertureless near-field microscopy that the so-calledp-polarization configuration, where the incident light is polarized parallel to the axis of the probe, is advantageous to its counterpart, thes-polarization configuration, where the incident light is polarized perpendicular to the probe axis. While this is true for most samples under common near-field experimental conditions, there are samples which respond better to thes-polarization configuration due to their orientations. Indeed, there have been several reports that have discussed such samples. This leads us to an important requirement that the near-field experimental setup should be equipped with proper sensitivity for measurements withs-polarization configuration. This requires not only creation of effective s-polarized illumination at the near-field probe, but also proper enhancement of s-polarized light by the probe. In this paper, we have examined thes-polarization enhancement sensitivity of near-field probes by measuring and evaluating the near-field Rayleigh scattering images constructed by a variety of probes. We found that thes-polarization enhancement sensitivity strongly depends on the sharpness of the apex of near-field probes. We have discussed the efficient value of probe sharpness by considering a balance between the enhancement and the spatial resolution, both of which are essential requirements of apertureless near-field microscopy.

scholarly journals Polarimetric Imaging in the Environment Containing Medium and Object

2022 ◽  
Vol 9 ◽  
Author(s):  
Daqian Wang ◽  
Xin Wang ◽  
Peifeng Pan ◽  
Jun Gao
Keyword(s):  
Polarized Light ◽  
Scattering Medium ◽  
Complex Environment ◽  
Simulation Experiments ◽  
Experimental Conditions ◽  
Polarimetric Imaging ◽  
Simulation Results ◽  
The Difference ◽  
Difference Imaging ◽  
Circular Polarized Light

Polarimetric imaging has been studied and applied to the problem of visibility restoration in various scenarios such as haze, mist and underwater. Although studies have shown that under certain conditions, circular polarimetric imaging has certain advantages over linear polarimetric imaging, however, for a complex environment containing both scattering medium and object, the performance of linear and circular polarimetric imaging is affected by many factors. In this paper, the propagation of linear and circular polarized light in the scattering medium is theoretically analyzed, then the simulation experiments under different experimental conditions are carried out and the conclusions are summarized. In order to validate the simulation results, the measurement experiments are carried out in dynamic smoke scenarios with different smoke concentrations. The results show that, the propagation of the polarized light, especially the circular polarized light, is determined by medium conditions. Generally, both the linear and circular polarimetric imaging had an ability to reduce the image degradation caused by smoke, however, under some certain environment conditions, unlike the linear polarized channels, the difference between the orthogonal circular polarized channels may be approached or even reversed, which may limit the circular polarization-based difference imaging and visibility restoration performance.

A Comparative Study of the Endocrine System of the Honey Bee Larvae under Normal and Experimental Conditions

1977 ◽  
Vol 32 (7-8) ◽  
pp. 637-642 ◽  
Author(s):  
G. S. Dogra ◽  
G. M. Ulrich ◽  
H. Rembold
Keyword(s):  
Honey Bee ◽  
Larval Instar ◽  
Endocrine System ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Neurosecretory Material ◽  
Experimental Conditions ◽  
Histological Techniques ◽  
Larval Stages ◽  
Queen Larvae

Abstract The endocrine system of the honey bee (Apis mellifera L.) has been studied morphologically through post-embryonic development with several histological techniques. Marked differences in the structure of the neurosecretory complex of queen and worker larvae have been observed during larval stages. In queen larvae, morphogenesis of the neurosecretory cells, their axons and the formation of the chiasma takes place during end of 2nd and beginning of 3rd, in the workers at beginning of 4th larval instar. Stainable neurosecretory material was found in queen larvae at the beginning, in worker larvae at the end of 4th instar. In early larval stages, the corpora allata are more active in the queen. During initial 3 - 5 days of larval development the gland volume is reduced in both castes. After 36 to 48 hours of endocrine retardation, the glands become active again. The same histological effects are found under experimental conditions, where worker larvae of 2nd instar were reared in the incubator on basic food, Royal Jelly and with topically applied juvenile hormone I.

Memoirs: The Muscles of the Adult Honey-Bee (Apis Mellifera L.)

1928 ◽  
Vol s2-72 (287) ◽  
pp. 511-526
Author(s):  
GUY D. MORISON
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Polarized Light ◽  
Muscular Contraction ◽  
Ph Values

1. The chemistry of the muscles is described in outline. With it are included pH values and pigment. 2. The appearance of muscle under polarized light is discussed. 3. The effects of age and fatigue on muscle could not be determined by the techniques adopted. 4. The theories of muscular contraction are summarized briefly.

Polarized light orientation of the honey bee: The minimum visual angle

1976 ◽  
Vol 109 (3) ◽  
pp. 309-314 ◽  
Author(s):  
Wolfgang Edrich ◽  
Otto von Heiversen
Keyword(s):  
Honey Bee ◽  
Visual Angle ◽  
Polarized Light

High Voltage Electron Microscopy of Ion-Milled Dental Enamel

1974 ◽  
Vol 32 ◽  
pp. 60-61
Author(s):  
L. D. Ackerman ◽  
S. H. Y. Wei
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Third Molar ◽  
Polarized Light ◽  
Dental Enamel ◽  
Longitudinal Section ◽  
Ion Milling ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron

Mature human dental enamel has presented investigators with several difficulties in ultramicrotomy of specimens for electron microscopy due to its high degree of mineralization. This study explores the possibility of combining ion-milling and high voltage electron microscopy as a means of circumventing the problems of ultramicrotomy.A longitudinal section of an extracted human third molar was ground to a thickness of about 30 um and polarized light micrographs were taken. The specimen was attached to a single hole grid and thinned by argon-ion bombardment at 15° incidence while rotating at 15 rpm. The beam current in each of two guns was 50 μA with an accelerating voltage of 4 kV. A 20 nm carbon coating was evaporated onto the specimen to prevent an electron charge from building up during electron microscopy.

Electrolytic Isolation of Twin-Type Shock Deformation Structures

1967 ◽  
Vol 25 ◽  
pp. 318-319
Author(s):  
F. I. Grace ◽  
L. E. Murr
Keyword(s):  
Grain Boundaries ◽  
Thin Foil ◽  
Electrolyte Composition ◽  
Experimental Conditions ◽  
Average Current Density ◽  
Electron Transmission ◽  
Deformation Structures ◽  
The Matrix ◽  
Average Current ◽  
Specimen Edge

During the course of electron transmission investigations of the deformation structures associated with shock-loaded thin foil specimens of 70/30 brass, it was observed that in a number of instances preferential etching occurred along grain boundaries; and that the degree of etching appeared to depend upon the various experimental conditions prevailing during electropolishing. These included the electrolyte composition, the average current density, and the temperature in the vicinity of the specimen. In the specific case of 70/30 brass shock-loaded at pressures in the range 200-400 kilobars, the predominant mode of deformation was observed to be twin-type faults which in several cases exhibited preferential etching similar to that observed along grain boundaries. A novel feature of this particular phenomenon was that in certain cases, especially for twins located in the vicinity of the specimen edge, the etching or preferential electropolishing literally isolated these structures from the matrix.

Site of Lysosome Production During Hepatic Injury

1969 ◽  
Vol 27 ◽  
pp. 348-349
Author(s):  
Nalin J. Unakar
Keyword(s):  
Electron Microscopy ◽  
Golgi Apparatus ◽  
Mouse Liver ◽  
Hepatic Injury ◽  
Close Approximation ◽  
Experimental Conditions ◽  
Toxic Injury

The increased number of lysosomes as well as the close approximation of lysosomes to the Golgi apparatus in tissue under variety of experimental conditions is commonly observed. These observations suggest Golgi involvement in lysosomal production. The role of the Golgi apparatus in the production of lysosomes in mouse liver was studied by electron microscopy of liver following toxic injury by CCI4.

Optimizing conditions for x-ray microchemical analysis in analytical electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 548-549 ◽  
Author(s):  
N. J. Zaluzec
Keyword(s):  
Solid Angle ◽  
Analytical Electron Microscopy ◽  
Incident Beam ◽  
Thin Foil ◽  
Experimental Conditions ◽  
X Ray ◽  
Microchemical Analysis ◽  
Analytical Electron ◽  
Image Position ◽  
Incident Beam Energy

The ultimate sensitivity of microchemical analysis using x-ray emission rests in selecting those experimental conditions which will maximize the measured peak-to-background (P/B) ratio. This paper presents the results of calculations aimed at determining the influence of incident beam energy, detector/specimen geometry and specimen composition on the P/B ratio for ideally thin samples (i.e., the effects of scattering and absorption are considered negligible). As such it is assumed that the complications resulting from system peaks, bremsstrahlung fluorescence, electron tails and specimen contamination have been eliminated and that one needs only to consider the physics of the generation/emission process.The number of characteristic x-ray photons (Ip) emitted from a thin foil of thickness dt into the solid angle dΩ is given by the well-known equation

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