We investigated the effect of head-down bed rest (HDBR) for 14 days on thermoregulatory sweating and cutaneous vasodilation in humans. Fluid intake was ad libitum during HDBR. We induced whole body heating by increasing skin temperature for 1 h with a water-perfused blanket through which hot water (42 degrees C) was circulated. The experimental room was air-conditioned (27 degrees C, 30-40% rel...

The temperature dependence of below-threshold emission from multiple quantum well semiconductor lasers is well characterized by a power law, in excellent agreement with Landau-Ginzburg theory of second-order phase transitions. We thereby show that it is the temperature dependence of net gain and not that of nonradiative recombination which primarily determines temperature sensitivity of thresho...

The temperature sensitivity of laser threshold current in single mode, wavelength tunable, InGaAsP bulk active region semiconductor lasers diodes is measured in the temperature range, 293 K 6 T 6 355 K and wavelength range 1.23 pm il < <, 1.35 pm. When proper account is taken of peak gain variation with temperature, the temperature dependence of laser threshold current (parameterized by T,) is ...

We developed a subthreshold CMOS circuit whose dynamical behavior, e.g., oscillatory or stationary behaviors, changes at a given threshold temperature with the aim of the development of low-power and compact temperature switch devices on monolithic ICs. The threshold temperature is set to a desired value by adjusting an external bias voltage. The circuit consists of two pMOS differential pairs,...

PURPOSE To analyze in vivo end temperatures and histologic injury in a standardized cryo-iceball using a porcine kidney model in order to establish the threshold temperature for tissue ablation. To evaluate the ability to predict end temperatures using a thermal finite element model. MATERIALS AND METHODS A single freeze/thaw cryolesion was created in five pig kidneys and the temperature hist...

We show that even in quantum-dot (QD) lasers with very low threshold current densities (Jth = 40–50 A/cm at 300 K), the temperature sensitivity of the threshold current arises from nonradiative recombination that comprises ∼60% to 70% of Jth at 300 K, whereas the radiative part of Jth is almost temperature insensitive. The influence of the nonradiative recombination mechanism decreases with inc...