Mechanical Seal Application - A User's Viewpoint

TutorialPg. 171-185.The purpose of this paper is to present some user guidelines for the selection, operation, and maintenance of mechanical end face seals in chemical, petrochemical, and petroleum operations. Though the exact seal requirements for a similar service may differ between the authors, we are all looking for a means of improving our mechanical seal reliability. For the majority of services, there are several seal vendors and installation schemes that will work equally well for that service, while for certain services, only one seal vendor may excel with a limited installation scheme variation. The reasons that a particular plant uses a certain seal for their general plant service relates more to the local service representative, parts availability, materials offered, seal arrangement or seal type. Conversely, your plant should not be stuck in the dilemma that the plant preferred seal has to fit all applications because of spare parts of “maintenance know-how to work with this seal.” Every seal design has strong and weak design points. Learn what they are and know how to best apply and maintain your plant seals

Hepatocyte nuclear factor-4 alpha mediates the stimulatory effect of peroxisome proliferator-activated receptor gamma co-activator-1 alpha (PGC-1 alpha) on glucose-6-phosphatase catalytic subunit gene transcription in H4IIE cells.

It has recently been shown that adenoviral-mediated expression of peroxisome proliferator-activated receptor gamma co-activator-1 alpha (PGC-1 alpha) in hepatocytes stimulates glucose-6-phosphatase catalytic subunit (G6Pase) gene expression. A combination of fusion gene, gel retardation and chromatin immunoprecipitation assays revealed that, in H4IIE cells, PGC-1 alpha mediates this stimulation through an evolutionarily conserved region of the G6Pase promoter that binds hepatocyte nuclear factor-4 alpha

Individuality and ethnicity eclipse a short-term dietary intervention in shaping microbiomes and viromes.

Many diseases linked with ethnic health disparities associate with changes in microbial communities in the United States, but the causes and persistence of ethnicity-associated microbiome variation are not understood. For instance, microbiome studies that strictly control for diet across ethnically diverse populations are lacking. Here, we performed multiomic profiling over a 9-day period that included a 4-day controlled vegetarian diet intervention in a defined geographic location across 36 healthy Black and White females of similar age, weight, habitual diets, and health status. We demonstrate that individuality and ethnicity account for roughly 70% to 88% and 2% to 10% of taxonomic variation, respectively, eclipsing the effects a short-term diet intervention in shaping gut and oral microbiomes and gut viromes. Persistent variation between ethnicities occurs for microbial and viral taxa and various metagenomic functions, including several gut KEGG orthologs, oral carbohydrate active enzyme categories, cluster of orthologous groups of proteins, and antibiotic-resistant gene categories. In contrast to the gut and oral microbiome data, the urine and plasma metabolites tend to decouple from ethnicity and more strongly associate with diet. These longitudinal, multiomic profiles paired with a dietary intervention illuminate previously unrecognized associations of ethnicity with metagenomic and viromic features across body sites and cohorts within a single geographic location, highlighting the importance of accounting for human microbiome variation in research, health determinants, and eventual therapies. Trial Registration: ClinicalTrials.gov ClinicalTrials.gov Identifier: NCT03314194