Succinate-cytochrome c reductase activity and lipids in diapause and non-diapause Anthonomus grandis from different latitudes

Succinate-cytochrome c reductase (SCR) activity and fat content were compared for diapausing and non-diapausing boll weevils, Anthonomus grandis, collected from various latitudes. Thoracic mitochondrial SCR activity was unaffected by diapause; however, the SCR activity of abdominal mitochondria was reduced by 50% in diapausing weevils and the fat content increased by 2-fold. Diapausing weevils from the southernmost latitude showed the lowest SCR activity and the lowest fat content and were distinct from the other diapausing groups. No correlation was found between northern latitudes and SCR activity during diapause. The significance of the results is discussed from the standpoint of food quality and the evolution of diapause in the boll weevil.     

Temperature dependence of active K+ transport in cation dimorphic sheep erythrocytes

Arrhenius diagrams of K⁺ pump fluxes measured between 15°C and 41°C were discontinuous in high K⁺ but not in low K⁺ sheep red cells. Exposure of low K⁺ cells to anti-L caused a bimodal temperature response of K⁺ pump flux with a transition temperature, $\text{T}\text{c}$, similar to that found in high K⁺ cells but with comparatively higher activation energies above $\text{T}\text{c}$.     

Aspects of hadrosaurian cranial anatomy

Supraorbital bones in Saurolophus angustirostris are described, and their presence in all hadrosaurs is suggested. Frontal-nasal and premaxillar-nasal fontanellae are distinguished in hadrosaurs; their presence is explained as connected with growth and considered to he responsible for the variability of crest structures. New data indicating the presence of a cartilaginous diverticulum nasi within the circumnarial depression in Saurobphus ongustirostris are presented. A physiological (respiratory and/or thermoregulatory) function of the nasal diverticulum is proposed.     

Unusual venoconstrictor effects of angiotensin II.

Cumulative dose-response curves to angiotensin II were performed on helical strips from canine lateral saphenous vein. Threshold concentrations were in the range of 10(-18)-10(-17)M. Increases in angiotensin from 10(-17)-10(-12)M failed to elicit further increases in tension. Subsequent increases in angiotensin concentration from 10(-11)-10(-7)M again produced dose-related increases in tension. Repeated dose-response curves in the same strips showed reduced maximal response. Responses to low concentrations of angiotensin were attenuated by low concentrations of phentolamine. These results suggest that, at extremely low concentrations angiotensin produced marked contractions in canine saphenous vein strips by releasing endogenous norepinephrine from sympathetic nerve terminals.     

Genetic and Anatomical Basis of the Barrier Separating Wakefulness and Anesthetic-Induced Unresponsiveness

A robust, bistable switch regulates the fluctuations between wakefulness and natural sleep as well as those between wakefulness and anesthetic-induced unresponsiveness. We previously provided experimental evidence for the existence of a behavioral barrier to transitions between these states of arousal, which we call neural inertia. Here we show that neural inertia is controlled by processes that contribute to sleep homeostasis and requires four genes involved in electrical excitability: Sh, sss, na and unc79. Although loss of function mutations in these genes can increase or decrease sensitivity to anesthesia induction, surprisingly, they all collapse neural inertia. These effects are genetically selective: neural inertia is not perturbed by loss-of-function mutations in all genes required for the sleep/wake cycle. These effects are also anatomically selective: sss acts in different neurons to influence arousal-promoting and arousal-suppressing processes underlying neural inertia. Supporting the idea that anesthesia and sleep share some, but not all, genetic and anatomical arousal-regulating pathways, we demonstrate that increasing homeostatic sleep drive widens the neural inertial barrier. We propose that processes selectively contributing to sleep homeostasis and neural inertia may be impaired in pathophysiological conditions such as coma and persistent vegetative states.     

European checkerspots (Melitaeini: Lepidoptera,Nymphalidae) are not aposematic – the point of view of great tits (Parus major)

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Multiplex panels of polymorphic microsatellite loci for two cryptic bat species of the genus Pipistrellus,developed by cross‐species amplification within the family Vespertilionidae

The paper presents multiplex panels of polymorphic microsatellites for two closely related cryptic species Pipistrellus pipistrellus and Pipistrellus pygmaeus. We tested the cross‐species amplification of 34 microsatellite loci, originally developed for five vespertilionid bat species. Ten and nine polymorphic loci in P. pipistrellus (mean number of alleles per locus = 10.5) and P. pygmaeus (8.1), respectively, in three multiplex polymerase chain reactions per species were amplified. All loci can be analysed in a single fragment analysis and can be used as markers to the study of evolution and the ecology of structured populations of socially living bats.