DISCONTINUOUS RESPIRATION IN INSECTS AT LOW TEMPERATURES: INTRATRACHEAL PRESSURE CHANGES AND SPIRACULAR VALVE BEHAVIOR

High-Pressure Behavior of Hydrogen and Deuterium at Low Temperatures.

In situ high-pressure low-temperature high-quality Raman data for hydrogen and deuterium demonstrate the presence of a novel phase, phase II^{'}, unique to deuterium and distinct from the known phase II. Phase II^{'} of D_{2} is not observed in hydrogen, making it the only phase that does not exist in both isotopes and occupies a significant part of P-T space from ∼25 to 110 GPa and below 125 K...

The Ballistic Behavior of High Strength, Low Alloy-100 Steel at Sub-zero Temperatures

The ballistic response of the high strength, low alloy (HSLA-100) steel at ambient and temperatures of -400°C, -800°C and -1960°C is investigated in this work. Lambert-jonas equation is used to fit the experimental results into a curve. The effect of quenching on ballistic behavior of HSLA-100 is also studied. The experiments are conducted on 3mm thick rectangular specimens impacted by blunt ti...

Pressure-induced superconducting state of europium metal at low temperatures.

Divalent Eu (4f;{7}, J=7/2) possesses a strong local magnetic moment which suppresses superconductivity. Under sufficient pressure it is anticipated that Eu will become trivalent (4f;{6}, J=0) and a weak Van Vleck paramagnet, thus opening the door for a possible superconducting state, in analogy with Am metal (5f;{6}, J=0) which superconducts at 0.79 K. We present ac susceptibility and electric...

Observations on spiracular behavior in Aedes mosquitoes.

Temperature-dependent variation in gas exchange patterns and spiracular control in Rhodnius prolixus.

Insects display an array of respiratory behaviors, including the use of discontinuous gas exchange. This pattern is characterized by periods of spiracular closure, micro-openings (flutter), and complete openings during which the majority of gas exchange takes place. A current model of insect spiracular control suggests that spiracles are controlled by two interacting feedback loops, which produ...