An automatic image analysis system for RLGS films

The RLGS (Restriction Landmark Genome Scanning) method was originally developed as a powerful method for enabling viewing of thousands of restriction landmarks. It offers a tool for obtaining information about genetic loci, with a single RLGS profile displaying approximately 2000 restriction landmarks as spots. One of the most useful applications is RLGS spot mapping, which allows the efficient, low-cost construction of the genetic map of any organism. However, analyses of the profiles depend mainly on human visual observation and are tedious and laborious. Although several commercially available image analyzing systems for profile comparison have been examined, they cannot be used for the RLGS spot mapping system owing to the background characteristics of the RLGS profiles, unsatisfactory rates of correspondence, and inefficient correction of informative genetic data. We therefore developed a novel automatic image analysis system for RLGS spot mapping, using an original algorithm based on the binary image transferred from the original RLGS profile. This system was employed for identifying non-polymorphic and parental strain-specific polymorphic spots of the F₁ mouse profile and yielded efficient initial screening of RLGS profiles. Received: 5 December 1997 / Accepted: 6 April 1998     

An HPLC system for the automatic sampling and analysis of time-series kinetic studies

Robotics were used to automate a high performance liquid chromatography (HPLC) system which was designed for the unattended sampling and analysis of time-series kinetic studies. The system allowed for the direct injection of samples containing whole cells and particulates witout plugging the analytical column. Coarse debris was removed from the injected sample by a 0.5 μm inline filter. Finer particulates were removed by a guard column that was layered with three different size packing resins. To demonstrate the system's capabilities, data are presented from an 8 day progress curve showing the anaerobic biodegradation of p-cresol by a sulfate-reducing enrichment. On fitting the data to the Michaelis-Menten equation by nonlinear regression, the apparent kinetic constants K_m and V_max were calculated to be 126 μM and 4.0 μM/h, respectively, for p-cresol metabolism by the enrichment.     

An automatic system for chromosomal analysis applied to prenatal diagnosis

Summary Computer-assisted metaphase analysis for prenatal diagnosis can be economically performed by a preexisting hardware-software system. The program can be run by technician-level (i.e., nonspecialist) personnel who can opt for the automatic operational mode for good quality metaphases or for the semimanual mode for problem metaphases (numerous superpositions, artifacts, etc.). The karyotype can be obtained in conversational mode. Hardcopy output is available for all modes.     

An experimental metagenome data management and analysis system

The application of shotgun sequencing to environmental samples has revealed a new universe of microbial community genomes (metagenomes) involving previously uncultured organisms. Metagenome analysis, which is expected to provide a comprehensive picture of the gene functions and metabolic capacity for microbial communities, needs to be conducted in the context of a comprehensive data management and analysis system. We present in this paper IMG/M, an experimental metagenome data management and analysis system that is based on the Integrated Microbial Genomes (IMG) system. IMG/M provides tools and viewers for analyzing both metagenomes and isolate genomes individually or in a comparative context. IMG/M is available at http://img.jgi.doe.gov/m.     

Ecology and behaviour of a free-swimming tube-dwelling rotifer Cephalodellaforficula

SUMMARY. 1. Cephalodella for ficula (Ploima, Rotifera) lives in tubes it constructs itself. These tubes are built of mueus in detritus-rich environments. The tubes are often closed at both ends, arc not used as sieves, and are not eaten directly.
2. The rotifer swims back and forth in its tube and apparently lives on bacteria which are shed from the inner walls of the tubes. Because of surface-to-volume considerations, this feeding strategy is probably only possible for animals smaller than roughly 1 mm. Under low food conditions, rotifers inside a tube have a distinctly higher fitness than rotifers removed from their tube.
3. Given high food conditions, rotifers removed from a tube immediately build another. Grazing on particles outside the tube appears to take place when a tube is being lengthened. Rotifers do not leave the tube for routine feeding, but under conditions of starvation or very low oxygen concentration they will leave the tube and swim about.     

Control of feeding behaviour and selective cannibalism in the rotifer Asplanchna

SUMMARY. Feeding responses in campanulate females of Asplanchna sieboldi were induced with filtrates of homogenized saccate female clonemates, showing that such behaviour can be triggered entirely by chemical stimuli. The failure of campanulates to attack campanulate clonemates, however, probably cannot be explained by the tissue chemistry of these females – filtered and unfiltered homogenates of campanulates were as active as those of saccates—and appears to be a function of some property limited to the campanulate body surface.
The roles of chemical and physical properties of food items in controlling feeding behaviour in Asplanchna and other rotifers are considered.     

Validation of a new system for the automatic registration of behaviour in mice and rats

A newly developed behaviour registration system, Laboratory Animal Behaviour Observation, Registration and Analysis System (LABORAS) for the automatic registration of different behavioural elements of mice and rats was validated. The LABORAS sensor platform records vibrations evoked by animal movements and the LABORAS software translates these into the corresponding behaviours. Data obtained by using LABORAS were compared with data from conventional observation methods (observations of videotapes by human observers). The results indicate that LABORAS is a reliable system for the automated registration of eating, drinking, grooming, climbing, resting and locomotion of mice during a prolonged period of time. In rats, grooming, locomotion and resting also met the pre-defined validation criteria. The system can reduce observation labour and time considerably.     

Morphometric requirements for image analysis and the IBAS interactive automatic image analysis system

The morphometric demands made on an image analysis system are discussed, as is the IBAS interactive automatic system, which meets those requirements. The modular design of the IBAS image analysis system, with its tailor-made processors for image processing, system control and pattern recognition, gives speed and flexibility. The IMAGE image analysis language guarantees user friendliness, and, last but not least, the enormous amount of software offers accurate, reproducible measurements and dedicated evaluation programs.     

New trace fossil evidence for eurypterid swimming behaviour

We describe a recently discovered trace fossil from a eurypterid Konservat‐Lagerstätte in the upper Silurian Tonoloway Formation of Pennsylvania, and formally describe contemporaneous traces from the Williamsville Formation Lagerstätte of Ontario. The traces from both localities are assigned here to Arcuites bertiensis igen. et isp. nov. Based on comparisons with previously described eurypterid trackways, neoichnological experiments, and the co‐occurrence with eurypterid remains, Arcuites is interpreted as having been made by the swimming leg (sixth prosomal appendage) of swimming juvenile to adult eurypteroid eurypterids, and represents the first unambiguous trace fossil evidence for eurypterid swimming behaviour. The morphology of Arcuites indicates that eurypteroid eurypterids swam using drag‐based rowing, whereby the animal propelled itself forward by moving its oar blade‐like swimming paddles in an in‐phase backstroke. Arcuites morphology also indicates that the eurypteroid swimming appendage had a greater degree of movement than was previously suggested, and a revised rowing model is proposed. Differences in the abundance of A. bertiensis in the Tonoloway and Williamsville formations suggest a bathymetric control on eurypterid swimming behaviour and trace production. The association of Arcuites with eurypterid body fossils in both units indicates that these Lagerstätten were autochthonous assemblages and provides additional evidence for eurypterid inhabitation of shallow subtidal marine environments in the late Silurian.     

An analysis of the nonlinear behaviour of the human thermal vasomotor control system.

Specific aspects of the activity of the human thermoregulatory system are analysed from the point of view of the associated biological rhythms. Fluctuations in digit blood flow were examined and analysis of them showed that they were consistent with a nonlinear model of the control system. Experiments were undertaken in which periodic thermal stimuli were applied which caused the entrainment of digit blood flow. A theoretical study was subsequently undertaken in which the experimental results were compared to the activity of a Van der Pol oscillator.     

Isozyme analysis of rotifer proteins

An analysis of isozyme variation of five enzymes among 17 strains of the brackish-water rotifer, Brachionus plicatilis, using thin-layer polyacrylamide electrophoresis, showed that it was possible to resolve genetic differences. It is suggested that isozyme characters will be useful in distinguishing sub-species of the group.     

An entrainment model for semilunar rhythmic swimming behaviour in the marine isopod Eurydice pulchra Leach

Entrainment experiments have been carried out with geographically widely separated populations of the sand beach isopod Eurydice pulchra Leach subjected to periods of simulated tidal agitation imposed concurrently with a 24-h light: dark (L: D) cycle. Circatidal swimming rhythms of greatest amplitude were induced when agitation was applied with the subjective timing, within the L: D cycle, of local spring high tides. This occurred in a normal L: D regime and also when the L: D regime was phase shifted through 90°. Animals previously maintained in constant darkness (D: D) and subsequently exposed to simulated tidal disturbance at various times in constant darkness were unable to modulate the amplitude of circatidal swimming activity. Isopods previously maintained in a normal L: D cycle and subsequently subjected to artificial tidal agitation in constant darkness were, however, able to modulate circatidal activity. This indicates that E. pulchra is capable of detecting tidal agitation and daily light cues and using them in conjunction with its circadian “clock” to modulate its endogenous circatidal rhythmicity. The free-running semilunar rhythm of swimming activity entrained only when the timing of agitation within the day/night cycle mimicked the pattern of local spring high tides. Agitation with the timing of neap high tides entrained no free-running circa-semilunar activity pattern.     

Sensory receptors involved in the feeding behaviour of the rotifer Asplanchna brightwelli

A study of the anterior sensory receptors of male and female Asplanchna brightwelli by scanning electron microscopy reveals some important differences in the region surrounding the mouth. In the male, the ventrolateral sensory bristles, the pseudotrochus, the inner and the outer buccal tufts and the mastax receptors are absent. The oral receptors are reduced. Transmission electron microscopy of these receptors shows that they consist of ciliated sensory cells surrounded by epithelial supporting cells. The distal ends of the cilia of the mastax receptors are modified; the cilia of the other receptors differ only in their length and rootlet structure from the locomotor cilia of the cingulum. A consideration of the feeding behaviour of Asplanchna leads us to suppose that these sensory cilia function in mechanoreception and in chemoreception.     

An electromagnetic tracking system for use in shallow water

Modifications to an electromagnetic method of tracking juvenile western rock lobsters Panulirus cygnus George are documented. The receiving aerials were made more robust to increase their useful life, and an automated tracking system was developed. The system continuously collects data on the movements of up to 14 tagged lobsters simultaneously. The feasibility of the method and its problems are discussed and suggestions are made for its improvement. The susceptibility to wave action of the aerials and the main communication cable that brings the signals to shore suggest that electromagnetic tracking is feasible only in calm and shallow environments.     

Optimization and performance validation for the fully automatic blood type analysis system

To evaluate and validate the application of fully automatic blood type analysis system parameters under actual lab conditions. All key system parameters were optimized and validated accordingly. The optimized parameters were centrifugal speed at 550 rpm; centrifugal time 20 min; resuspension speed 1,200 rpm; resuspension time: 45 s; incubation temperature 25℃ ; incubation time 400 s; incubation rate: 0 rpm. The sampled red blood cell concentration was 3%. The ratio of plasma to red blood cells reagent was 60 μL:30 μL; the ratio of antibody (reagent) to sampled diluted red blood cell was 30 μL:30 μL. After applying our key parameters for optimization and validation, the automatic blood type detection system's performance was found to meet the relevant requirements, effectively improving the accuracy and reliability of the detection system.     

Use of swimming speed and egg ratio as predictors of the status of rotifer cultures in aquaculture

This study evaluated the use of egg ratio (eggs rotifer^–1) and swimming speed (mm min^–1) as prediction criteria for production and culture quality in mass cultures of the rotifer Brachionus plicatilis. Egg ratio was determined to be a suitable predictor of rotifer growth and production in the cultures. Low egg ratios (i.e., 0–0.17 eggs rotifer^–1) indicate reduced rotifer population over time (i.e., negative net population growth rates). However, at this time egg ratio dynamics are not suitably understood to predict in advance a sudden population collapse.Swimming speed of reproductive, egg-carrying females in the exponential growth phase was 40–45 mm min^–1. During exponential growth swimming speed was independent of the food used. Lower swimming speeds were obtained in late stationary phase (10–25 mm min^–1) when yeast was used as a food source. Both environmental factors (e.g., accumulating metabolites) and changes in nutritional state of the rotifers may have affected the swimming speed, but environmental factors appear to be the most important. We believe that swimming speed has the potential of becoming an accurate predictor of culture quality in mass cultures of rotifers.