The American Conference of Governmental Industrial hygienists (ACGIH) lowered the threshold limit value (TLV) for respirable crystalline silica (RCS) exposure from 0.05 to 0.025 mg m(-3) in 2006. For a working environment with an airborne dust concentration near this lowered TLV, the sample collected with current standard respirable aerosol samplers might not provide enough RCS for quantitative...

Monte Carlo sampling methods are the standard procedure for approximating complicated integrals of multidimensional posterior distributions in Bayesian inference. In this work, we focus on class Layered Adaptive Importance Sampling (LAIS) scheme, which is a family adaptive importance samplers where Markov chain algorithms employed to drive an underlying multiple scheme. The modular nature LAIS ...

A review is given on the development of passive samplers for aquatic environments. Passive samplers that are simple and easy to use and with minimal consumption of organic solvents to desorb the analytes from the trapping media are focused. New developments in quality assurance procedures are highlighted.

Design of optimal signal reconstructors over all samplers and holds boils down to canceling frequency bands from a given frequency response. This paper discusses limits of performance of such samplers and holds and develops methods to compute the optimal L2-norm.

New generation ambient air samplers operate at much lower sampling flow rates than do their “high volume” predecessors, namely 16.7 liters/minute. When these new air samplers emerged several years ago there were limited tools available with which to assess and calibrate their operating flow rate. In 1996 a flow meter specifically designed for these new air samplers came available, known as the ...

Passive sampling was used to deduce water concentrations of persistent organic pollutants (POPs) in the vicinity of a marine Superfund site on the Palos Verdes Shelf, California, USA. Precalibrated solid phase microextraction (SPME) fibers and polyethylene (PE) strips that were preloaded with performance reference compounds (PRCs) were codeployed for 32 d along an 11-station gradient at bottom,...

Epidemiology studies of health effects from air pollution, as well as impact assessments, typically rely on ambient monitoring data or modelled residential levels. The relationship between these and personal exposure is not clear. To investigate personal exposure to NO(2) and its relationship with other exposure metrics and time-activity patterns in a randomly selected sample of healthy working...

Recently, Hofheinz, Jager, Khurana, Sahai, Waters and Zhandry [9] proposed a new primitive called universal samplers that allows oblivious sampling from arbitrary distributions, and showed how to construct universal samplers using indistinguishability obfuscation (iO) in the ROM. One important limitation for applying universal samplers in practice is that the constructions are built upon indist...

Urban air background concentrations of benzene, toluene, ethylbenzene, and xylenes (BTEX) were measured in 2007 in the Tricity area (Gdansk, Gdynia, and Sopot) and Tczew applying two types of passive samplers: Home-made permeation passive samplers and two diffusive passive samplers Orsa 5 (National Dräger) and Radiello (FS Maugeri). Differences between the time-weighted annual averages concentr...