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The increase of electron temperature as a function of the incident r-f. power of a cylindrical plasma column in a wave guide at the dipole resonance is studied. Measured values are consistent with the view that the electron temperature is limited by inelastic collisions. Section III of the paper uses an equivalent circuit model of the plasma column to explain theoretically the observed deformation of the dipole resonance curve with increasing incident r-f. power. All features of the experimentally observed deformation are successfully explained.

En este articulo se dan criterios para elegir entre diversas leyes de probabilidad, tratandose en el primer capitulo solamente de la existencia de estimadores suficientes (resumenes exhaustivos).

Pendant la periode de reproduction, les nephrons du rein de l'Epinoche mâle subissent d'importantes modifications de structure sous l'action des hormones sexuelles. Au niveau de chacun d'entre eux, se differencient deux segments distincts par leur fonction et par leur cytologie. Le segment urinaire, tres court, est forme de cellules identiques a celles du jeune, qui remplissent leur fonction d'excretion. Le segment glandulaire, plus volumineux, subit une transformation muqueuse et elabore une secretion qui sert a construire le nid. L'evolution de ces deux segments est etudiee au cours de la periode de reproduction et les modifications cytologiques correspondantes sont decrites.

Heavy damage to the cattle industry in tropical Latin America by Dermatobia hominis (L., Jr.) furnished economic justification for research on the sterile-male approach to eradication of this species. A method of colonizing D. hominis by use of a natural host for rearing the larvae is described, along with techniques for collecting the full-grown larvae, holding the pupae and adults, inducing mating and oviposition in small cages, and infesting the hosts.

Au microscope electronique, l'action de la methyltestosterone sur les cellules renales de l'Epinoche femelle se traduit par une cytodifferenciation conduisant a la formation de cellules glandulaires muqueuses. Elle a lieu simultanement a deux niveaux distincts

Female odor apparently plays a minor role or none at all in the mating of Dermatobia hominis (L., Jr.); the principal stimuli leading to the meeting of the sexes probably are visual. Courtship and mating behavior are described. The flies remained in copula an average of 9 minutes (range 4–21 minutes), and both sexes mated repeatedly. The flies reached sexual maturity at about 1½–4 hours after emergence. Strong light and a temperature of about 28°C were favorable to mating. A character needed to distinguish the sexes was found in the fifth abdominal sternite, which is about twice as broad in the male as in the female.

Pupae of the torsalo (human hot fly), Dermatobia hominis (L., Jr.), which had completed 20, 25, and 30 days, respectively, of their pupal development were exposed to dosages of 5000, 7500, and 10,000 R of gamma radiation from a cobalt60 source. These exploratory tests indicated that the best age for treating pupae was 25 days, representing about 5/7 of their development at 25°C. All dosages drastically reduced fertility of the flies, but the results obtained here suggest that 7500 R (which completely inhibited development of ova in females and reduced male fertility to 0.8%) is the appropriate dosage for practical use in control of this fly by sterile-male release. Behavior and appearance of the treated flies appeared normal; mating frequency of males treated with 7500 R was like that of normal males, and they competed equally with untreated males for mates in small cages. Sperm of treated males were motile and equaled in quantity that of untreated flies.

L’objet de cet article est de rappeler quelques definitions et theoremes du calcul des probabilites, d’en deduire la representation mathematique de bruits intervenant dans de nombreux cas concrets, et de souligner les precautions a prendre lorsque l’on effectue des passages a la limite, en particulier l’extension d’une bande passante finie a une bande infinie. Ainsi peuvent etre ecartees les contradictions apparentes de divers travaux publies sur le

A resonance phenomenon observed in confinement by crossed fields (very high frequency electric field perpendicular to the static magnetic field) is described. This phenomenon leads apparently to the stable confinement of a plasma sphere. The experimental study of the evolution of the phenomenon, as well as its interpretation, seems to prove a relation with the THETA pinch. (tr-auth)

The experimental results previously reported (Phys. Letters, 1 : 267(1962)) are tentatively interpreted using four designs. If the self-field reduces locally the static field, resonance is possible on both sides of the median plane of symmetry only where the initial static field reduced from the self-field can engender two new rings. The plasma resulting from the bursting of the central ring forms a plasma sphere that is trapped in the small magnetic bottle. This structure remains stable until the end of the pulse. When the neutral pressure is higher, this evolution is not observed, but the formation of a cylindrical bed is. A probable prolongation of the preceding phases is given. (J.S.R.)

Le tube fonctionne aux alentours de 0,60 metres, les performances demandees sont: 25 kW entre 390 et 560 Mc/s.

L'etude de la structure fine de Rhabdospora thelohani permet de preciser les caracteristiques structurales de cette espece. Il s'agit d'un parasite extracellulaire frequent chez les Poissons, qui presente une polarite tres nette: le pole apical, tourne vers la lumiere des tubules renaux, est occupe par une masse mitochondriale compacte; le pole basal contient le noyau et l'appareil de Golgi. L'aspect caracteristique de ce Protiste est determine par deux structures particulieres. La premiere resulte de l'organisation du cytoplasme peripherique en une couche dense riche en fibrilles, qui correspond a la coque observee en microscopie optique. Dans la partie centrale, vesiculaire, on distingue plusieurs organites en forme de massue ressemblant a certains trichocystes.