Cold environmental temperatures increase sympathetic nerve activity and blood pressure, and increase the risk of acute cardiovascular events in aged individuals. The acute risk of cardiovascular events increases with aortic pulse wave velocity as well as elevated central and peripheral pulse pressures. The aim of this study was to examine the independent influence of aortic pulse wave velocity ...

The purpose of this study was to determine the effects of acute cold exposure on the timing and amplitude of central aortic wave reflection and central pressure. We hypothesized that cold exposure would result in an early return of reflected pressure waves from the periphery and an increase in central aortic systolic pressure as a result of cold-induced vasoconstriction. Twelve apparently healt...

intense temperature variations are not only an unfavorable phenomenon for life but have adverse effects on natural elements of structures and installations. when the temperature falls bellow certain levels, the conditions for organic activity become harsh. this level is known as temperature threshold of life. similar thresholds can also be defined for machinery, structures and installations. fu...

We describe a method for nondegenerate four-wave-mixing in a cold sample of four-level atoms. An integral part of the four-wave-mixing process is a collective instability which spontaneously generates a periodic density modulation in the cold atomic sample with a period equal to half of the wavelength of the generated high-frequency optical field. Because of the generation of this density modul...

A short-wave train emanating from the Southeast Asian tropics which links interannual variations of the winter climate systems in both East Asia and North America was identified recently. This shortwave train may affect the activity of cold-surge disturbances over the eastern seaboard of East Asia, and the northwestern Pacific. The interaction between cold surges and the planetary-scale winter ...

The effect of electron collisions on reducing the wave-breaking amplitude of resonantly-driven electrostatic fields in a cold plasma is investigated. By means of a simple theory collisions are shown to compete with wave-breaking in dissipating wave energy.

In recent years, extreme events related to cooling and heating have taken high resonance, motivating the scientific community to carry out an intensive research activity, aimed to detect their variability and frequency. In this work, we have investigated about the frequency, the duration, the severity and the intensity of heat and cold waves in a Southern Italy high-altitude region, by analysin...

The eeect of orographically generated breaking gravity waves is parametrised in a global circulation model of the Martian atmosphere using schemes adapted from terrestrial models. The schemes arètuned' by comparing model integrations with and without gravity wave drag with temperatures derived from the Mariner 9 IRIS instrument. Without gravity wave drag the global circulation model temperature...