Disease control is of paramount importance in public health, with infectious disease extinction as the ultimate goal. Although diseases may go extinct due to random loss of effective contacts where the infection is transmitted to new susceptible individuals, the time to extinction in the absence of control may be prohibitively long. Intervention controls are typically defined on a deterministic...

We present near-IR imaging polarimetry observations of the nucleus of Cygnus A, taken with the NICMOS camera of the HST at a wavelength of 2.0µm. These maps reveal a highly collimated region of polarized emission straddling the nucleus and extending to a radius of 1.2 arcseconds. Remarkably, this feature coincides with one, but only one, limb of the edge-brightened bicone structure seen in the ...

Nephelometry is a laser based imaging technique, which uses the signal of light scattered off particles to provide information about the local number density of these particles. In densely seeded flows of practical interest, such as pulverised coal flames, particle loadings can become very high, to the point where the incident laser beam is severely attenuated. Therefore, measurements in flows ...

In this paper, we report on the production of a Bose–Einstein condensate (BEC) of sodium using light–induced desorption as an atomic source. We load about 2 × 10 atoms in a MOT from this source with a ∼ 6 s loading time constant. The MOT lifetime can be kept around 27 s by turning off the desorbing light after loading. We show that the pressure drops down by a factor of 40 in less than 100 ms a...

Light has been used to treat disease since the dawn of time. Nevertheless, its popularity has fluctuated over the years. Early use, such as that recorded by the Greeks and Romans, emphasized its thermal effects and, as recently as the early 1900's, the Nobel Prize in Physics was awarded for the use of the ultraviolet portion of the light spectrum in the treatment of tuberculosis. Subsequent imp...

All-optical switching is a technique in which a gate light pulse changes the transmission of a target light pulse without the detour via electronic signal processing. We take this to the quantum regime, where the incoming gate light pulse contains only one photon on average. The gate pulse is stored as a Rydberg excitation in an ultracold atomic gas using electromagnetically induced transparenc...

We demonstrate the generation of light in an optical waveguide strongly coupled to a periodic array of metallic nanoantennas. This coupling gives rise to hybrid waveguide-plasmon polaritons (WPPs), which undergo a transmutation from plasmon to waveguide mode and vice versa as the eigenfrequency detuning of the bare states transits through zero. Near zero detuning, the structure is nearly transp...

Visible light extinction was measured in a series of nitrogen-diluted, ethylene/air, non-premixed flames and this data was used to determine the optical band gap, OBG, as a function of flame position. Collimated light from a supercontinuum source is telescopically expanded and refocused to match the f- number of a dispersing monochromator. The dispersed light is split into a power metering chan...

Frustration represents a particular aspect of the addictive process that is related to loss of control when the expected reward is not obtained. We aim to study the consequences of frustrated expected reward on gene expression in the mouse brain. For this purpose, we used an operant model of frustration using palatable food as reward combined with microarrays. Transcriptomic profiles of frontal...

In fall-winter, 2007-2013, visibility and light scattering coefficients (bsp) were measured along with PM2.5 mass concentrations and chemical compositions at a background site in the Pearl River Delta (PRD) region. The daily average visibility increased significantly (p<0.01) at a rate of 1.1 km/year, yet its median stabilized at ~13 km. No haze days occurred when the 24-hr mean PM2.5 mass conc...