Day- and night-time parental investment by incubating Wilson's Plovers in a tropical environment

1995 ◽  
Vol 73 (5) ◽  
pp. 879-886 ◽  
Author(s):  
Michel Thibault ◽  
Raymond McNeil
Keyword(s):  
Breeding Season ◽  
Nest Predation ◽  
Time Lapse ◽  
Video Camera ◽  
Nest Attendance ◽  
Night Time ◽  
Low Light ◽  
Charadrius Wilsonia ◽  
Infrared Lamps ◽  
Time Lapse Video

With the use of a time-lapse video camera and infrared lamps, we quantified diurnal and nocturnal incubation sex roles in 17 pairs of Wilson's Plovers (Charadrius wilsonia cinnamominus) breeding in northeastern Venezuela. More than 82% of nests reached the hatching stage. Between the laying of the last egg and hatching of the first one, parents devoted 83% of their time incubating. Males spent more time incubating than females. Males incubated mainly at night and females mostly during daytime. Males also spent significantly more time incubating during daytime than did females during nighttime. During incubation, females relieved males at dawn and males relieved females at dusk. By relieving each other under conditions of low light intensity, parents probably reduced nest predation. Outside the breeding season, the Wilson's Plovers forage almost exclusively during nighttime. In contrast, during the breeding season, males foraged mainly during daytime low tides, probably as a consequence of their nocturnal nest attendance. During short daytime periods, on cloudy days, incubating plovers, particularly the females, abandoned their eggs to forage.

Time-lapse Video Photography: A Low-tech Way to Make Plants Dance

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 568c-568
Author(s):  
H.C. Wien ◽  
R.J. Sloan
Keyword(s):  
Time Lapse ◽  
Video Camera ◽  
Vegetable Crops ◽  
Growth Processes ◽  
Horticultural Crops ◽  
Head Formation ◽  
Speed Up ◽  
Visual Impact ◽  
Set Up ◽  
Time Lapse Video

The growth processes of most horticultural crops are too slow to be visually interesting to students. Time lapse photography has been used for years to speed up the action and make plants “come alive.” With the advent of video technology, time lapse techniques have become convenient, easy, and affordable. The system which we have found satisfactory consists of a time lapse video cassette recorder, linked by optical fiber cable to a closed circuit color video camera in a ventilated housing. Typically, the camera has been set up in a greenhouse compartment, monitoring growth processes of vegetable crops, and linked by cable to the VCR in an office 80 m away. Equipment costs with one camera are less than $3000. Two cameras can be set up to do comparative growth studies, with two images side-by-side, using a screen splitter. Costs of the latter system is about $4500. Growth processes such as cabbage head formation, curd growth in cauliflower, and weed-crop competition of mustard and peas have been the subjects so far. The technique lends itself to increasing the visual impact of teaching, and gaining a better understanding of plant growth processes in research.

scholarly journals Photogrammetric Digital Surface Model Reconstruction in Extreme Low-Light Environments

2021 ◽  
Vol 13 (7) ◽  
pp. 1261
Author(s):  
Riccardo Roncella ◽  
Nazarena Bruno ◽  
Fabrizio Diotri ◽  
Klaus Thoeni ◽  
Anna Giacomini
Keyword(s):  
Image Quality ◽  
Image Quality Assessment ◽  
High Sensitivity ◽  
Sensor Technology ◽  
Surface Model ◽  
Night Time ◽  
Low Light ◽  
Reduction Techniques ◽  
Geometrical Information ◽  
Imaging Sensors

Digital surface models (DSM) have become one of the main sources of geometrical information for a broad range of applications. Image-based systems typically rely on passive sensors which can represent a strong limitation in several survey activities (e.g., night-time monitoring, underground survey and night surveillance). However, recent progresses in sensor technology allow very high sensitivity which drastically improves low-light image quality by applying innovative noise reduction techniques. This work focuses on the performances of night-time photogrammetric systems devoted to the monitoring of rock slopes. The study investigates the application of different camera settings and their reliability to produce accurate DSM. A total of 672 stereo-pairs acquired with high-sensitivity cameras (Nikon D800 and D810) at three different testing sites were considered. The dataset includes different camera configurations (ISO speed, shutter speed, aperture and image under-/over-exposure). The use of image quality assessment (IQA) methods to evaluate the quality of the images prior to the 3D reconstruction is investigated. The results show that modern high-sensitivity cameras allow the reconstruction of accurate DSM in an extreme low-light environment and, exploiting the correct camera setup, achieving comparable results to daylight acquisitions. This makes imaging sensors extremely versatile for monitoring applications at generally low costs.

Motion of Active Fluids: Diffusion Dynamics of Cyanobacteria

2016 ◽  
Author(s):  
Thomas Vourc’h ◽  
Julien Léopoldès ◽  
Annick Méjean ◽  
Hassan Peerhossaini
Keyword(s):  
Time Lapse ◽  
Global Behavior ◽  
Diffusion Dynamics ◽  
Mean Squared Displacement ◽  
Terrestrial Environments ◽  
The Mean ◽  
Micro Organisms ◽  
Synechocystis Sp ◽  
Time Lapse Video ◽  
Pcc 6803

Cyanobacteria are photosynthetic micro-organisms colonizing all aquatic and terrestrial environments. The motility of such living micro-organisms should make their diffusion distinct from typical Brownian motion. This diffusion can be investigated in terms of global behavior (Fickian or not) and in terms of displacement probabilities, which provide more detail about the motility process. Using cyanobacterium Synechocystis sp. PCC 6803 as the model micro-organism, we carry out time-lapse video microscopy to track and analyze the bacteria’s trajectories, from which we compute the mean-squared displacement (MSD) and the distribution function of displacement probabilities. We find that the motility of Synechocystis sp. PCC 6803 is intermittent: high-motility “run” phases are separated by low-motility “tumble” phases corresponding to trapped states. However, this intermittent motility leads to a Fickian diffusive behavior, as shown by the evolution of the MSD with time.

scholarly journals Salmonella stimulate macrophage macropinocytosis and persist within spacious phagosomes.

1994 ◽  
Vol 179 (2) ◽  
pp. 601-608 ◽  
Author(s):  
C M Alpuche-Aranda ◽  
E L Racoosin ◽  
J A Swanson ◽  
S I Miller
Keyword(s):  
Bone Marrow ◽  
Plasma Membrane ◽  
Time Lapse ◽  
Membrane Ruffling ◽  
Mouse Macrophages ◽  
Constitutive Mutation ◽  
Microscopic Studies ◽  
Specific Igg ◽  
Salmonella Survival ◽  
Time Lapse Video

Light microscopic studies of phagocytosis showed that Salmonella typhimurium entered mouse macrophages enclosed in spacious phagosomes (SP). Viewed by time-lapse video microscopy, bone marrow-derived macrophages exposed to S. typhimurium displayed generalized plasma membrane ruffling and macropinocytosis. Phagosomes containing Salmonella were morphologically indistinguishable from macropinosomes. SP formation was observed after several methods of bacterial opsonization, although bacteria opsonized with specific IgG appeared initially in small phagosomes that later enlarged. In contrast to macropinosomes induced by growth factors, which shrink completely within 15 min, SP persisted in the cytoplasm, enlarging often by fusion with macropinosomes or other SP. A Salmonella strain containing a constitutive mutation in the phoP virulence regulatory locus (PhoPc) induced significantly fewer SP. Similar to Yersinia enterocolitica, PhoPc bacteria entered macrophages in close-fitting phagosomes, consistent with that expected for conventional receptor-mediated phagocytosis. These results suggest that formation of SP contributes to Salmonella survival and virulence.

Collecting Vehicle-Speed Data by Using Time-Lapse Video Recording Equipment

2003 ◽  
Vol 1855 (1) ◽  
pp. 97-104 ◽  
Author(s):  
Christopher Strong ◽  
Scott Lowry ◽  
Peter McCarthy
Keyword(s):  
Real Time ◽  
Video Recording ◽  
Warning System ◽  
Time Lapse ◽  
Vehicle Speed ◽  
Recording Equipment ◽  
Safety Improvement ◽  
Camera Location ◽  
Message Signs ◽  
Time Lapse Video

An innovative application of time-lapse video recording is used to assist in an evaluation of a highway safety improvement. The improvement is an icy-curve warning system near Fredonyer Summit in northern California that activates real-time motorist warnings via extinguishable message signs, based on weather readings collected from road weather information systems. A measure of effectiveness is whether motorist speed is reduced as a result of real-time warnings to drivers. Why indirect speed measurement with video was preferred over radar for this case is discussed, as is how specific methodological issues related to the custom-built equipment, including camera location and orientation, distance benchmarking, and data collection and reduction. Theoretical and empirical accuracy measurements show that the video surveillance trailers yield results comparable to radar and, hence, would be applicable for studies in which speed change is measured. Because this particular technology had not been used previously, several lessons are documented that may help determine where and how similar equipment may be optimally used in future studies.

An automatic time lapse video system for optical microscopy

1991 ◽  
Vol 22 (3) ◽  
pp. 275-276
Author(s):  
B. Nys ◽  
A. Van Daele ◽  
W. Jacob
Keyword(s):  
Optical Microscopy ◽  
Time Lapse ◽  
Video System ◽  
Time Lapse Video
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