The diagnostic value of the hemagglutination inhibition test for Newcastle disease has been established for some years (Brandly et al., 1946). The question of the relationship of the hemagglutination inhibition activity (HI) of immune sera to virus-neutralizing activity (SN) or to the refractivity of the host to challenge infection is still one of both fundamental and practical importance. Data...

A technique for high-precision and high-accuracy assessment of both gas molar (and number) density pressure, Gas Modulation Refractometry (GAMOR), is presented. The achieves its properties by assessing refractivity as a shift directly measurable beat frequency use Fabry-Perot cavity (FPC) based refractometry utilizing the Pound-Drever-Hall laser locking technique. Conventional FPC-based is, how...

We compare the random error statistics (uncertainties) of COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate, C1) COSMIC-2 (C2) radio occultation (RO) bending angles refractivities months August 2006 2021 over tropics subtropics using three-cornered hat method. The uncertainty profiles are similar two RO missions in troposphere. However, a higher percentage C2 reach ...

Reference refractivity values have been derived for the anaesthetic agents halothane, isoflurane, enflurane, sevoflurane and desflurane which are traceable to national measurement standards. A simple method and equation have been derived for the application of these data to the measurement of agent concentration by refractometry. The main instrumental sources of uncertainty associated with this...

Abstract Due to climate change, intensive storms and severe precipitation will continue happen, causing destructive flooding. In July 2021, a series of with prolonged rain episodes took place in Europe. Several countries were affected by floods following that rainfall, many deaths material damage. Thus, good understanding forecasting such events are uttermost importance. This study highlights t...

The theoretical background and present status of formulas for the refractive index of air are reviewed. In supplement to Edlén's recently revised formula for relative refractivity, the density dependence of refractive index is reanalyzed. New formulas are presented for both phase and group refractive index which are more useful over a wide range of pressure, temperature, and composition than an...

The ITU Radiocommunication Assembly, considering a) that for the proper planning of terrestrial and Earth-space links it is necessary to have appropriate calculation procedures for assessing the refractivity effects on radio signals; b) that procedures have been developed that allow the calculation of some refractive propagation effects on radio signals on terrestrial and Earth-space links, rec...

The Global Positioning System/Meteorology (GPS/MET) Program was established in 1993 by the University Corporation for Atmospheric Research (UCAR) to demonstrate active limb sounding of the Earth's atmosphere using the radio occultation technique. The demonstration system observes occulted GPS satellite signals received by a low Earth orbiting (LEO) satellite, MicroLab1, launched April 3, 1995. ...