The air in the respiratory system of diving birds contains a large proportion of the body oxygen stores, but it must be in the lungs for gas exchange with blood to occur. To test the hypothesis that locomotion induces mixing of air sac air with lung air during dives, we measured differential pressures between the interclavicular and posterior thoracic air sacs in five diving tufted ducks Aythya...

BACKGROUND Developing retinas display retinal waves, the patterned spontaneous activity essential for circuit refinement. During the first postnatal week in rodents, retinal waves are mediated by synaptic transmission between starburst amacrine cells (SACs) and retinal ganglion cells (RGCs). The neuromodulator adenosine is essential for the generation of retinal waves. However, the cellular bas...

bacterial utilize a multitude of methods to secretion of specific substrate across phospholipid membranes. these bacterial strategies can play many roles in promoting bacterial process, from enhancing pathogenesis to bacterial response to environmental condition. the secretion in bacterial species transfer and release performance substance such as proteins, enzymes and metabolites to environmen...

background: fasciola hepatica is one of the most important helminthes parasites and triclabendazole (tcbz) is routinely used for treatment of infected people and animals. secreted protease enzymes by the f. hepatica plays a critical role in the inva-sion, migration, nutrition and the survival of parasite and are key targets for novel drugs and vaccines. the aim of study was to determine the pro...

background: the aim of this study was to compare superoxide dismutase (sod) activity in fasciola hepatica and fasciola gigantica parasites. materials: f. gigantica and f. hepatica helminths were collected from abattoir and cultured in buffer media for 4 h at 37 °c. excretory-secretory (es) products were collected, centrifuged and stored at - 20 ◦ c. e-s protein concentration was measured by bra...

Electrolytic hydrogen is expected to play a key role in the production of green fuels and chemicals, while contributing balancing consumption supply future electricity grid relying largely on intermittent renewable sources for energy production. However, oxygen evolution reaction (OER) major bottleneck boosting conversion efficiency due sluggish kinetics four-electron transfer process. Intensiv...

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Electromyographic (EMG) activity of skeletal muscles that either insert on the skin or are associated with the margins of subcutaneous lymph sacs was monitored for two species of anurans, Chaunus marinus and Lithobates catesbeiana (formerly Bufo marinus and Rana catesbeiana). Our hypothesis was that contraction of these muscles varies the volume, and hence pressure, within these lymph sacs, and...

17 Dendritic and axonal arbors of many neuronal types exhibit self-avoidance, in which branches 18 repel each other. In some cases, these neurites interact with those of neighboring neurons, a 19 phenomenon called self/non-self discrimination. The functional roles of these processes remain 20 unknown. Here, we used retinal starburst amacrine cells (SACs), critical components of a 21 direction-s...