Circadian periodicity in termination of photorefractoriness in the yellow-throated sparrow

Summary Photorefractory male yellow-throated sparrows (Gymnorhis xanthocollis) were subjected to six resonance light cycles, consisting of 6 h basic photophase coupled with scotophases of longer durations (in cycles of 12 (6L6D) h, 24 (6L18D) h, 36 (6L30D) h, 48 (6L42D) h, 60 (6L54D) h and 72 (6L66D) h). Termination of photorefractoriness was evident in cycles of 24, 48 and 72 h, but not in 12, 36 and 60 h. The results are consistent with the external-coincidence model (Bünning hypothesis) and suggest that endogenous circadian rhythmicity is involved in the termination of photorefractoriness.To whom reprint requests should be addressed.This investigation was supported by a UGC grant to PDT and BHU to PMT.     

The trail and alarm pheromones of the ant,Pristomyrmex pungens Mayr

Summary The trail and alarm pheromones of P. pungens were investigated. The nine fatty acids (C₁₄₀, C₁₆₀, C₁₆₁, C₁₈₀, C₁₈₁, C₁₈₂, C₁₈₃, C₂₀₄, C₂₀₅) were the components of the trail pheromone, while the alarm pheromone was found to be the mixture of 4 monoterpene hydrocarbons (-pinene, camphene, -pinene, limonene).The authors are indebted to Dr Masao Kubota for identification of the ant.     

Synthesis of oxytocin: Suppression of dimer formation

Zusammenfassung Die Bildung von Oxytocin-Dimer (+), einem Nebenprodukt der Oxytocin-Synthese, wird verringert durch Ausschluss atmosphärischen Sauerstoffes während der Zyklisation von Oxytocein zu Oxytocin. Das Gleichgewichtsverhältnis von Monomer zu Dimer wird durchschnittlich von 41 auf 111 verbessert.     

Rudiments of an ability for time measurement in the cavernicolous fishAnoptichthys jordani hubbs and innes (pisces characidae)

Summary Rudiments of an ability for endogenous time-measuring are indicated a) by bimodal activity in the dark phase of LD-cycles of 1616 or 2424 h and b) by damped activity oscillations frequently follwoing a transition from LD to constant conditions. These oscillations always have the same period length as the applied LD.     

Zweidimensionale Dünnschichtchromatographie von Zuckern

Summary Complex sugar mixtures can be separated and identified by twodimensional thin-layer chromatography using borate-impregnated silica gel G/kieselguhr G as carrier material. The separation of the solvent mixtureiso-butanol/glacial acetic acid/water (541) during chromatography in the first dimension and the subsequent intermediate drying cause a polyzonal (graduated in zones) activation of the sorption layer. In this way, the critical sugar mixtures in one-dimensional thin-layer chromatography can be separated in the second dimension using the solvent system propanol/water (8.51.5) orn-propanol/dimethyl sulphoxide/water (8.60.50.9).     

Cellular antigens in myxo- and paramyxoviruses as revealed by immunodiffusion methods

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Synthesis of (±)-isoelliptone

Zusammenfassung Die Synthese von Isoellipton aus 2-Hydroxy-4, 5-dimethoxyfurano [3, 26, 7] isoflavon wird beschrieben.     

Effect of photoperiod and all-female grouping on the estrous cycle of the bandicoot rat,Bandicota bengalensis

Summary Female bandicoot rats showing irregular cycles in 12L12D, were exposed to light-darkness cycles of 1L23D, 4L20D and 8L16D. Significant regularization of the estrous cycle was observed in 8L16D with most of the rats exhibiting a regular 3-day cycle and the regularity was further enhanced by all-female grouping (4/cage).     

Magnetic resonance microscopy: in vivo sectioning of a developing insect

Summary The utility of magnetic resonance imaging vis-a-vis insect morphology and development was investigated. MRI is a noninvasive technique that distinguishes between tissues based on proton content and proton environment. At present a resolution of 100 m is achievable. The technique avoids fixation artifacts and allows the detection of motion within the organism.     

The role of the pentose-phosphate pathway in adjustment of the heart to a high load and the development of myocardial hypertrophy

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Mass spectrometric determination of the amino acid sequence in cystine- and cysteine-containing peptides

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Mass spectrometric determination of the amino acid sequence in peptides: Desulfurization of sulfur-containing peptides

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Chromosomes and giemsa-bands of the Idaho spotted ground squirrel,Spermophilus brunneus (Howell)

-Spermophilus brunneus . , 13 18 ,S. brunneus S. townsendii mollis (2n=38) , , ; ;S. brunneus . S. brunneus , Spermophilus.

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Supported by National Science Foundation Grants No. GB32114X and No. GB 29131X, and the Sprague Foundation. We thankD. Pozin for technical assistance.     

G-band patterns as chromosomal markers,and the interpretation of chromosomal evolution in wild sheep (Ovis)

- . Ovis musimon (2n=54) O. orientalis (2n=54) - - -O. canadensis mexicana (2n=54) O. musimon x O. canadensis ₁₂ - . ₂ 27 . - .

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Supported by National Science Foundation Grant no. GB 32114X and the Sprague Foundation. We thank Dr. T. C. Hsu for assistance in making the chromosome preparations and for advice and encouragement. The Trustees of the Rachelwood Wildlife Research Preserve generously allowed the biopsy of specimens of their custody. Mr.Arthur Popham kindly provided the specimens from Iran while Dr.R. M. Robinson obtained biopsies from the desert sheep.     

Correlation between sensitivity to trypaflavine and DNA base composition in mutants ofBacterium paracoli 5099

Bacterium paracoli 5099 , , .     

Magnug reflexex of the chest musculature in man

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The participation of kinins in the pathogenesis of early disturbances in the skin capillary permeability in localβ-ray irradiation

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Effect of unsaturation in fatty acid-induced swelling of rat liver mitochondria

Zusammenfassung In Gegenwart von Öl-(181), Linol-(182) oder Arachidonsäure (204) wurde eine konzentrationsabhängige, proportional zur Zahl der Doppelbindungen verlaufende Schwellung von Rattenleber Mitochondrien beobachtet. Die Fettsäure-Albumin Komplexe unterscheiden sich von den Natriumsalzen durch eine Lag-Phase vor Beginn der Schwellung gefolgt von einer stärkeren Schwellungsamplitude.     

IdentifyingY chromosome in interphase nuclei of the human brain

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Chromosomes and some issues of the evolution of the ground squirrel genusCitellus (Rodentia: Sciuridae)

Citellus (s. str.) relictus, C. dauricus C. pygmaeus (2=36, NF=72). . (Colobotis) erythrogenys . fulvus -. . (Urocitellus) undulatus (2n=32, NF=64) . columbianus. Citellus, , Citellus, . , .