We report an experimental implementation of long-range polarimetric imaging through fog over kilometric distance in real field atmospheric conditions. An incoherent polarized light source settled on a telecommunication tower is imaged at a 1.3 km distance with a snapshot polarimetric camera including a birefringent Wollaston prism, allowing simultaneous acquisition of two images along orthogonal polarization directions. From a large number of acquisitions datasets and under various environmental conditions (clear sky/fog/haze, day/night), we compare the efficiency of using polarized light for source contrast increase with different signal representations (intensity, polarimetric difference, polarimetric contrast,...). With the limited-dynamics detector used, a maximum fourfold increase in contrast was demonstrated under bright background illumination using polarimetric difference image. OCIS codes:(110.0113) Imaging through turbid media; (110.5405) Polarimetric imaging; (010.7295) Visibility and imaging; (110.4280 Noise in imaging systems).http://dx

We report our studies of emission from a dye-scatterer system, commonly known as random amplifying medium (RAM). It is found to exhibit non-Gaussian statistics of emission intensity over the ensemble of random realizations. The amplification is dominated by certain improbable events that are "larger than rare", which give the intensity statistics a Lévy-like fat tail. This, to the best of our knowledge, provides the first experimental realization of the Lévy statistics in the optics of a random amplifying medium, and the analysis thereof. Notably, the Lévy exponent is continuously tunable parametrically.

A modified optical tweezers set-up has been used to generate microbubbles in flowing, biologically relevant fluids and human whole blood that contains carbon nanotubes (CNTs) using low power (< or =5 mW), infrared (1064 nm wavelength), continuous wave laser light. Temperature driven effects at the tweezers' focal point help to optically trap these microbubbles. It is observed that proximate CNTs are driven towards the focal spot where, on encountering the microbubble, they adhere to it. Such CNT-loaded microbubbles can be transported both along and against the flow of surrounding fluid, and can also be exploded to cause fragmentation of the bundles. Thus, microbubbles may be used for scavenging, transporting and dispersal of potentially toxic CNTs in biologically relevant environments.

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We report the observation of Lévy-like statistical configuration-to-configuration fluctuations in the intensity of emission from a novel system, the fiber-random amplifying medium, where active fiber segments are embedded randomly in a bulk of pointlike passive scatterers. Some rare configurations of fibers provide long, guided amplifying paths for the photons, leading to high jumps in the intensity, and thus to Lévy statistics. This system provides an optical realization of the Arrhenius cascade.

Mentoring is a service activity that librarians must engage in to ensure a smooth integration of new library faculty. This case study describes the process of implementing a new mentoring model approach in an academic library, the Resource Team Model (RTM). The California State University, Long Beach (CSULB) Resource Team is an innovative model of mentoring, coaching, and training which includes a broader network of support for mentors and mentees. 1 It is formed by a trinity of mentor librarians with different strengths who mobilize for six months to guide and support one new librarian. The main objectives of this model are to acclimatize the mentee to all areas of librarianship and to the culture of the new organization. The RTM ensures that new librarian menteeshave the tools and support to move seamlessly into the fabric of the organization and to flourish professionally as they move towards tenure. The RTM approach is not a group mentoring, a mutual mentoring network, or a mentoring circle model as described in the literature. The advantages and disadvantages of the model are discussed, and the strengths, weaknesses, opportunities, and pressures from both the mentor and mentee perspective at the CSULB University Library are examined.

We report enhanced emission and gain narrowing in Rhodamine 590 perchlorate dye in an aqueous suspension of polystyrene microspheres. A systematic experimental study of the threshold condition for and the gain narrowing of the stimulated emission over a wide range of dye concentrations and scatterer number densities showed several interesting features, even though the transport mean free path far exceeded the system size. The conventional diffusive-reactive approximation to radiative transfer in an inhomogeneously illuminated random amplifying medium, which is valid for a transport mean-free path much smaller than the system size, is clearly inapplicable here. We propose a new probabilistic approach for the present case of dense, random, weak scatterers involving the otherwise rare and ignorable sub-mean-free-path scatterings, now made effective by the high gain in the medium, which is consistent with experimentally observed features.

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