Distance Of Several Meters Research Articles

Observation of territorial life in breeding season of a pair of Jungle Crow Corvus macrorhynchos in City Tokyo

Fledged family lifeNest-leaving: Behaviors of chicks and parents at nest-leaving of chicks are summarized as followsFeeling near flying of chicks from nest, the female utters her soft nasal nga-notes addressing to chicks, lengthens the feeding intervals so as to invoke the nest-leaving mood of chicks by causing the restless irritation from increasing hunger. The male chiefly watches her, feeding the chicks with still longer intervals.From a few days before nest-leaving, the chicks stand on nest-wall, preening (taking off descamating sheath of growing feathers), stretching and with jumping or wing flapping excercise, and finally they leave the nest to perch on near branches. Then they gradually move to upward branches to roost there for the night.This is usually toward evening and the root of such nest-leaving behavior may be in correlation with inherent roosting drive.Having once left the nest, the chicks would not come back to, or roost, on the nest (although they may temporarily perch on it while moving through the branches).During the day, the fledged chicks sit still in the foliage, sleeping and waiting the parents for food. The feeding frequency by parents 4 days after chicks' flying was 1.3 times per hour.On the 3rd day after fledged, a chick could fly about 30m and on the 8th day they flew 40-50m and came back to their perch.At the first night of fledging from nest, the chicks roosted on perches where they sat during the day and parents took roost (both in 1969 and '70, though they flew off to "flock roost" in 1977) below the nest-tree ("nest-site roost"), as if to guard the chicks (which are sleeping above in the tree, keeping individual distance of several meters. This may have an effect of distrupting the predator's attention. Thereafter, the parents roosted either in "nest-site", "territory" roost or flew off to "flock roost", reacting to the condition of chicks (If fed enough the chicks roosted quietly but if not they were irritated by hunger and in this case parents' (female) reaction involved some judgment behavior (cf. Kuroda 1969).The period of fledged family life can be summarized by dividing four periods:1. First period from fledging to 4th or 5th day.The chicks rest and wait parents' feeding perched in nest-tree (or adjacent taller tree) where they roost at night. The parents may roost below in "nest-site roost" (guarding chicks) or in "territory roost", or flly off to "flock roost" (judging the condition of the chicks).2. Five to ten days after fledged.The chicks begin to fly around the nest-tree, and the parents guide them (one chick after another by repeated trips to and from the roost-site and chick) to "nest-site" roost to sleep there by family.3. Ten to twenty days after fledged.Fledged family accompanied by female may move around for food chiefly within 100m from the nest-tree. But, usually a delayed chick remains in the nest-tree a few more days. Parents may guide chicks to "territory roost" to roost by family. Territory defense of parents are weakened and their chick guard drive reaches to its peak. The begging voice of chicks get lauder.4. After twenty days from fledging.At about 20 days from fledging the young (now to be so called) may be guided by parents to "flock roost" about 1km apart. From this day, well grown young may join to young crow group of the "flock roost" area, and may not return to parents' territory. But, a delayed young, having guided by parents to "flock roost" a few days after well grown mates, would return to parents' territory by itself (possibly urged to do so by "loneliness".).Such a family life of parents and a delayed young may continue 50-100 days, during which the parents would never reject the young from their territory. But, the latter gradually behaves independent of parents, not returning to territory on some days, and finally deserts the territory.

Ammonia-pellet generation system for the Baseball II-T target plasma experiment

The irradiation of a small pellet by a pulsed laser is one method of producing a startup target plasma for plasma experiments employing neutral-beam injection. A system for generating charged, uniformly sized, solid-ammonia, 150-μm-diam, spherical pellets having a charge-to-mass ratio of 10−4 C/kg is described. These pellets are electrostatically guided at a speed of 32 m/sec (over a distance of several meters) to a laser focal zone. This complete system (pellet generation and pellet guidance) has been successfully operated on a 3-m test stand where 250-μm-diam pellets were regularly irradiated by a pulsed, 30-J CO2 laser. The system is now installed on the Baseball II-T experiment; in preliminary tests, several 150-μm-diam pellets were irradiated with the pulsed 300-J CO2 laser.

La Historia Natural y el Comportamiento de Zygopachylus albomarginis (Chamberlain) (Arachnida, Opiliones: Genylepidae)

Males of the phalangid Zygopachylms albomarginis (Chamberlain) construct nests which females visit to copulate and/or lay eggs. This type of behavior is unknown in other members of the order Opiliones. The males remain in their nests almost continuously for up to several months, and are capable of relocating their nests from distances of several meters; they defend the nests against other males, which occupy and defend vacated nests. Females lay only a few eggs during a given visit to a nest, and may restrict their visits to only one or two nests. Neither parasitism nor predation of eggs in nests was observed. Possible functions of the nests are discussed. LA FAMILIA GONYLEPTIDAE, la mas grande del suborden Laniatores, y casi enteramente confinada a Suramerica, es en muchos aspectos desconocida. Este estudio de Zygopachylus albomarginis (Ch.) parece ser el primero sobre la biologia de esta especie. La mayoria de las especies de esta familia y los

Adjustable Aperture Stop to Control the Divergence and Orientation of the Beam Emerging from a Vacuum Ultraviolet Monochromator

An adjustable aperture stop for use in controlling the direction and angular divergence of the beam of radiant flux emerging from a MacPherson 225 VUV monochromator is described. Such a stop facilitates measurements of specular reflectance vs angle of incidence and measurements of diffraction grating efficiency. A discussion of the degree of control exercised by the aperture over the beam cross section is given that is applicable to any monochromator fitted with an aperture stop. For this application, the distance from the grating to the aperture stop is larger than the grating focal length. The result is an imaging effect that provides sharper definition of the beam cross section when the aperture stop is between the entrance slit and grating than if the stop is between the grating and exit slit. This sharp definition persists up to distances of several meters beyond the exit slit and is useful when measuring the efficiency of concave diffraction gratings. A fixed direction of the beam from the MacPherson i strument can only be obtained with the aperture between the grating and exit slit which results in some loss of definition of the beam cross section. However, as long as the pathlength beyond the exit slit is restricted to a few tens of cm, the definition is sufficiently good for measurements of reflectance vs angle of incidence.

The carrier-loaded helium-jet transport method

The suitability of commercial helium loaded with small amounts of different gases or vapors for the transport of radioactive reaction products over distances of several meters has been investigated experimentally. Negative results were obtained with gaseous carriers. Transport efficiencies of 50 to 100% were obtained with carrier vapors. The vapor appears to form droplets in the system. The recoils are adsorbed physically by the droplets and carried with them through a capillary. There appears to be an active mechanism that forces the heavy constituents to the centre of the capillary cross section. The heavy constituents emerge from the capillary as a very narrow beam. Collection of the transported activity onto a metal foil in a vacuum chamber is possible only when the vapor pressure of the carrier is lower than the pressure of the collection chamber. Vacuum pump oil was found to meet this requirement. The transport and collection efficiency was studied as a function of the relative mass throughput of the oil vapor. A method for determining the optimum mass throughput of the carrier is demonstrated. The internal energetics of the system are discussed. The kinetic energy of a particle to be transported has to be higher than the average thermal energy in order to avoid adsorption onto the capillary walls. This can be achieved by increasing the mass of the particle by means of a carrier or by decreasing the system temperature. In a cooled system transport over long distances is possible even with pure helium. Application of the carrier-loaded transport method in on-line mass separators is discussed.

Helium-jet transportation of recoil atoms into a liquid phase

A rapid inexpensive method has been developed for transportation of recoiling short-lived radioactive nuclides from a target chamber over distances of several meters into a liquid phase. This allows rapid radiochemical separation of different elements. The carrier-loaded helium-jet transport technique is employed without a pumping system. The method would appear to be applicable to most chemical elements. The transport efficiency is higher than 50% and the transport time can be made much shorter than 1 s. Radiochemical separation times of a few seconds were achieved.

An astatic galvanometer giving high sensitivity and a short period

The figure of merit of a sensitive galvanometer depends to a preponderant degree upon the construction of its moving system. By providing the Broca galvanometer with a light magnet system of astatic type, containing four or eight magnets of cobalt steel, it is possible to increase the figure of merit about sixteen times. A suitable mirror enables the spot of light to be read accurately at a distance of several metres and the good astatic qualities of the moving system ensure considerable stability of zero even without magnetic shielding. The construction of the instrument has been slightly modified to allow the insertion of this system.