H Goodfellow | PubMed Health

PubMed1998

Dust control for material handling operations: a systematic approach.

Material handling operations are used widely in industry. Often they produce unacceptable levels of dust. This article proposes a systematic approach to dust control for material handling operations. It focuses on the appropriate dust control technologies for the wide range of material handling operations. Both dust collection and dust suppression systems are considered. Comparisons are made between competing technologies using available information. Relevant literature resources are compiled and synthesized to provide the reader with the most recent design and operational information. Important areas requiring further research and development work are identified.

Air Pollution↗

PubMed1992

Structure and function of the spoIIIJ gene of Bacillus subtilis: a vegetatively expressed gene that is essential for sigma G activity at an intermediate stage of sporulation.

The spo-87 mutation is one of two sporulation mutations originally used to define the spo0J locus of Bacillus subtilis. We now show that it blocks sporulation after completion of prespore engulfment (stage III). Surprisingly, the operon is expressed vegetatively, probably from a sigma A-dependent promoter, and its expression is shut down at the transcriptional level at about the onset of sporulation. DNA sequencing reveals that the locus defined by spo-87, which we now designate spoIIIJ, consists of a bicistronic operon. However, only the first gene is essential for sporulation; the function of the second cistron is cryptic. The predicted SpoIIIJ product has an M(r) of 29,409. It probably forms a lipoprotein and is rich in basic and hydrophobic amino acids. Mutations in spoIIIJ abolish the transcription of prespore-specific genes transcribed by the sigma G form of RNA polymerase but not transcription of the spoIIIG gene encoding sigma G. The SpoIIIJ product could be involved in a signal transduction pathway coupling gene expression in the prespore to events in the mother cell, or it could be necessary for essential metabolic interactions between the two cells.

Amino Acid Sequence↗