A model of social interactions shows why and when reputation concerns may support an ‘underclass’ culture of street crime where the incentives for such behavior are otherwise weak. Those who do not gain from street crime directly nevertheless find it optimal to invest in violence and thereby build a reputation that will earn them deference from the rest of the community. Even when the fraction ...

Power sanding exterior paint is a common practice during repainting of old houses in New Orleans, Louisiana, that triggers lead poisoning and releases more than Pb. In this study we quantified the Pb, zinc, cadmium, manganese, nickel, copper, cobalt, chromium, and vanadium in exterior paint samples collected from New Orleans homes (n = 31). We used interior dust wipes to compare two exterior ho...

TRAKER is a vehicle-based method for measuring road dust emissions. Particulate matter is sampled in front and behind a vehicle’s tire and the difference in PM concentration (TRAKER signal) is used to infer the airborne flux of particles from the roadway. Two independent tests indicated that the TRAKER signal increases as the cube of the speed for a given road dust loading. Simultaneous measure...

background to get more precise responses when gathering information about sensitive topics such as drug use, it is important to use the most optimal method. objectives this study was carried out to address the impact of three interview methods (street-based, household, and telephone interviews) on response pattern to sensitive and non-sensitive questions in terms of participation, disclosure an...

In a survey of quasar candidates selected by matching the FIRST and 2MASS catalogs, we have found two extraordinarily red quasars. FIRST J013435.7−093102 is a 1 Jy source at z = 2.216 and has B −K & 10, while FIRST J073820.1+275045 is a 2.5 mJy source at z=1.985 with B −K ≈ 8.4. FIRST J073820.1+275045 has strong absorption lines of Mg II and C IV in the rest frame of the quasar and is highly po...

the flame propagation through a coal dust-air mixture in a spherical vessel was studied by means of a one-dimensional, arrhenius-type kinetics and quasi-steady model. the model includes the evaporation of the volatile matter of dust particles into a known gaseous fuel (methane) and the single-stage reaction of the gas-phase combustion. effect of venting devices as safety idea and the radiation ...

the impacts of dust and sand storms (dss) on people, crops, livestock, infrastructure and health are well documented. data have accumulated on the deleterious effects of dust aerosols when they settle on plants. sand blasting of low growing plants is a common cause of failure in reforestation efforts. burial of plants by moving sands are also a cause of much damage. the physics of moving sand a...