A microbiological survey of the effectiveness of class II (laminar flow) 'safety' cabinets found in the UK in the last six years is recorded. Only two of the nine units tested approached the containment of aerosols achieved by a good class I (exhaust protective) cabinet. The others were potentially hazardous if used with pathogenic material. The National Sanitation Foundation and the British St...

A prospective study of the use of a laminar flow cabinet, an exhaust-ventilated safety hood, and the open bench for the microbiological examination of blood is described. Blood samples from 1600 patients were subcultured on the open bench, 2700 in a safety hood, and 2607 in a laminar flow cabinet. Use of the laminar flow cabinet produced a significantly greater level of contamination than the o...

Formaldehyde used for the disinfection of a laminar-flow biological safety cabinet was oxidatively degraded by using a catalyst. This technique reduced the formaldehyde concentration in the cabinet from about 5,000 to about 45 mg/m3 in 8 h. This technique should prove useful in other applications.

Harborage of Escherichia coli O157:H7 and Salmonella on animal hides at slaughter is the main source of beef carcass contamination during processing. Given this finding, interventions have been designed and implemented to target the hides of cattle following entry into beef processing plants. Previous interventions targeting hides have not been suitable for all beef processing plants because of...

Tests are reported on a modified laminar flow biological safety cabinet in which the return air plenum that conducts air from the work area to the high efficiency particulate air filters is under negative pressure. Freon gas released inside the cabinet could not be detected outside by a freon gas detection method capable of detecting 10(-6) cc/s. When T3 bacteriophage was aerosolized 5 cm outsi...

The objective of this study was to evaluate both condensing (wet) and non-condensing (dry) vaporous hydrogen peroxide (VHP) technologies for decontaminating a worst-case scenario Class II biosafety cabinet. A 23-year-old Class II, type A2 biosafety cabinet equipped with loaded HEPA filters and an inoperable blower was used for this study. Biological indicators were placed at various locations w...

Electrostatic charging of particles in enclosed spaces has been shown to be an effective means of reducing airborne dust. Dust generated during the hatching process has been strongly implicated in Salmonella transmission, which complicates the cleaning and disinfecting processes for hatchers. Following two preliminary trials in which dust reduction was measured, four trials were conducted to ev...

We want to build an agent that plans by imagining sequences of future states. Subjectively, these states seem very rich and detailed. Providing an agent with sufficiently rich knowledge about its world is an impediment to studying this kind of planning, so we have developed mechanisms for an agent to learn about its world. One mechanism learns dependencies between synchronous "snapshots" of the...

In this paper we consider a dynamic model of government formation and termination in parliamentary democracies that accounts for the following phenomena: (1) Cabinet terminations due to replacement or early election (2) Cabinet reshuf°es (3) Minority and Surplus governments; (4) the relative instability of minority governments. JEL classi ̄cation: D72, H19, C73.