4,838 research outputs found
Spatial and temporal variations in indoor environmental conditions, human occupancy, and operational characteristics in a new hospital building.
The dynamics of indoor environmental conditions, human occupancy, and operational characteristics of buildings influence human comfort and indoor environmental quality, including the survival and progression of microbial communities. A suite of continuous, long-term environmental and operational parameters were measured in ten patient rooms and two nurse stations in a new hospital building in Chicago, IL to characterize the indoor environment in which microbial samples were taken for the Hospital Microbiome Project. Measurements included environmental conditions (indoor dry-bulb temperature, relative humidity, humidity ratio, and illuminance) in the patient rooms and nurse stations; differential pressure between the patient rooms and hallways; surrogate measures for human occupancy and activity in the patient rooms using both indoor air CO2 concentrations and infrared doorway beam-break counters; and outdoor air fractions in the heating, ventilating, and air-conditioning systems serving the sampled spaces. Measurements were made at 5-minute intervals over consecutive days for nearly one year, providing a total of ∼8×106 data points. Indoor temperature, illuminance, and human occupancy/activity were all weakly correlated between rooms, while relative humidity, humidity ratio, and outdoor air fractions showed strong temporal (seasonal) patterns and strong spatial correlations between rooms. Differential pressure measurements confirmed that all patient rooms were operated at neutral pressure. The patient rooms averaged about 100 combined entrances and exits per day, which suggests they were relatively lightly occupied compared to higher traffic environments (e.g., retail buildings) and more similar to lower traffic office environments. There were also clear differences in several environmental parameters before and after the hospital was occupied with patients and staff. Characterizing and understanding factors that influence these building dynamics is vital for hospital environments, where they can impact patient health and the survival and spread of healthcare associated infections
Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination
The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72 h, the two invertebrate species significantly increased the DOU of sediments (13–14%), and no temporal variation occurred afterwards. Within contaminated sediments, it was already 24% higher before the introduction of the organisms, suggesting that uranium modified the sediment biogeochemistry. Although the two species firstly reacted by avoidance of contaminated sediment, they finally colonized it. Their bioturbation activity was reduced but, for T. tubifex, it remained sufficient to induce a release of uranium to the water column and an increase of the DOU (53%). These results highlight the necessity of further investigations to take into account the interactions between bioturbation, microbial metabolism and pollutants
Gossypol Toxicity in Feeder Lambs
The stimulus for the study of gossypol toxicity in lambs came directly from cases that were investigated at the Oklahoma Animal Disease Diagnostic Laboratory during the summer of 1985.Veterinary Patholog
Chromatin structure of the inactive X chromosome
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Biology, 1999.Vita.Includes bibliographical references.by Sandra L. Gilbert.Ph.D
Editorial: Advances in the Understanding of the Commensal Eukaryota and Viruses of the Herbivore Gut
Herbivores play an important role in the survival of humanity, contributing food and textiles, as well as social and economic value. For decades, optimizing the productivity, health, welfare, and environmental footprint of herbivorous animals, particularly ruminant livestock, has been the subject of an extensive, global research effort. Much of this research effort has focused on the herbivore gut. The specialized nature of the herbivore digestive tract and its resident microbes enables the breakdown of highly fibrous plant materials, which are unable to be utilized by omnivores and carnivores. In recent years, the bacteria and methanogenic archaea have been the major focus of research efforts, with the other gut microbes being understudied in comparison
On the mechanical modeling of cell components
Eukaryotic cells are complex systems which carry out a variety of different tasks. The current contribution gives insight into the modeling of some of their vital components and represents an overview of results achieved within the international D‐A‐CH project on computational modeling of transport processes in a cell. The first part of the contribution studies viscoelastic effects of cross‐linked actin network embedded in cytosol. The basic‐model is used to simulate the actin behavior at a microscopic level. It considers the influence of the physical length, the end‐to‐end distance and the stretch modulus in order to provide a relationship between the stretch of a single polymer chain and the applied tension force. The effective behavior of the cell cytoplasm is simulated by using the multiscale finite element method. Here, a standard large strain viscous approach is applied for the cytosol, while the generalized Maxwell model simulates viscous effects occurring in filaments due to deviatoric changes. The examples dealing with combinations of tension‐holding tests give insight into the effective behavior of the cytoplasm
The effects of immersive simulation on targeted collaboration skills among undergraduates in special education
The use of immersive simulation as a pedagogical tool has great potential for making a significant impact on student learning in higher education. In this study, the effect of immersive simulation was evaluated for a cohort of undergraduate special education majors. The investigation aimed to determine whether facilitating an immersive co-planning simulation would have an impact on targeted collaboration skills and whether vicarious observational learning would occur for students who observed the simulation. Pre-service teachers in special education were evaluated by their peers on their ability to demonstrate knowledge of (1) co-teaching and co-planning, (2) professional communication, and (3) supports for students with disabilities. The results indicate that they did a better job of facilitating a co-planning session after having first practiced doing so via immersive simulation during a previous class session. It was also discovered that vicarious observational learning during immersive simulation positively affected performance
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