A Cost-effective and Reliable Method to Predict Mechanical Stress in Single-use and Standard Pumps.

Pumps are mainly used when transferring sterile culture broths in biopharmaceutical and biotechnological production processes. However, during the pumping process shear forces occur which can lead to qualitative and/or quantitative product loss. To calculate the mechanical stress with limited experimental expense, an oil-water emulsion system was used, whose suitability was demonstrated for drop size detections in bioreactors(1).

Cultural investment: providing opportunities to reduce risky behavior among gay American Indian males.

Many gay American Indian (GAI) men feel alienated from their tribal, ceremonial and social communities because of homophobia and heterosexism. As a result, they often turn to their local gay community for social participation and sex opportunities. It is no secret that a significant aspect of some gay communities is socializing in local bars and clubs.

Capillary gas chromatography of cotton dusts associated with human pulmonary function studies.

The effects of geographical area of growth and cotton variety on pulmonary activity have been evaluated through human volunteer exposure studies conducted by NIOSH and USDA at the Cotton Quality Research Station, Clemson, S.C. These studies demonstrate that carding California cottons releases dust with less human pulmonary activity than dust released from the corresponding Mississippi cottons.

Human ventilatory response to washed and unwashed cottons from different growing areas.

Thirty volunteer subjects were exposed to controlled amounts of respirable dust generated by the carding of cotton in an experimental cardroom. Eighteen exposures each lasting six hours were performed while carding unwashed and washed cottons from the three major growing regions of the United States. Elutriated dust was analysed gravimetrically and was comparable (0.

Acute lung function response to cotton dust in atopic and non-atopic individuals.

Acute spirometric responses to inhaled cotton dust were examined in a population of 226 healthy, non-asthmatic adults whose atopic status had been evaluated by skin prick tests to 10 common environmental allergens. Exposure to cotton dust occurred in model cardrooms where elutriated dust levels were carefully controlled (1.02 mg/m3).

Cotton induced bronchoconstriction detected by a forced random noise oscillator.

Lung function responses to inhaled cotton dust were evaluated in a group of 58 healthy subjects by spirometry (MEFV curves) and forced random noise impedance parameters. Twenty-one of these subjects were also examined by body plethysmography to assess changes in airway resistance (Raw). For the study group as a whole, alterations in lung mechanical function after exposure to cotton dust were detected by maximal expiratory volumes and flows (p less than 0.

Acute bronchoconstriction induced by cotton dust: dose-related responses to endotoxin and other dust factors.

Fifty-four healthy humans, selected for their acute airway responsiveness to cotton dust, had spirometric tests immediately before and after 6 hours of exposure to card-generated cotton dust from seven different cottons (of several grades and growing regions). During exposures, we measured airborne concentrations of viable fungi and bacteria (total and gram negative), vertically elutriated gravimetric dust, and vertically elutriated endotoxin. Correlation between each of these five exposure indices and exposure-related acute changes in forced expiratory volume in 1 s showed a statistically significant relationship between all of the indices except concentration of viable fungi.

Dust levels and particle-size distributions in high-capacity cotton gins.

Dust samples were collected inside high-capacity cotton gins with the personal, stationary personal, and the vertical elutriator cotton dust samplers. Dust particles collected on the filters were sized with a particle measurement computer system. Particle-distribution data revealed that gin dust contains a high percentage of dust particles larger than 20 micrometers in diameter.